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Sample records for cdznte pixel detectors

  1. Pixelated CdZnTe drift detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl

    2005-01-01

    A technique, the so-called Drift Strip Method (DSM), for improving the CdZnTe detector energy response to hard X-rays and gamma-rays was applied as a pixel geometry. First tests have confirmed that this detector type provides excellent energy resolution and imaging performance. We specifically...... report on the performance of 3 mm thick prototype CZT drift pixel detectors fabricated using material from eV-products. We discuss issues associated with detector module performance. Characterization results obtained from several prototype drift pixel detectors are presented. Results of position...

  2. Gamma Spectroscopy with Pixellated CdZnTe Gamma Detectors

    International Nuclear Information System (INIS)

    Shor, A.; Mardor, I.; Eisen, Y.

    2002-01-01

    Pixellated CdZnTe detectors are good candidates for room temperature gamma detection requiring spectroscopic performance with imaging capabilities. The CdZnTe materials possess high resistivity and good electron charge transport properties. The poor charge transport for the holes inherent in the CdZnTe material can be circumvented by fabricating the electrodes in any one of a number of structures designed for unipolar charge detection[1]. Recent interest in efficient gamma detection at relatively higher gamma energies has imposed more stringent demands on the CdZnTe material and on detector design and optimization. We developed at Soreq a technique where signals from all pixels and from the common electrode are processed, and then a correction is applied for improving the energy resolution and the photopeak efficiency. For illumination with an un-collimated 133 Ba source , we obtain a combined detector energy resolution of 5.0 % FWHM for the 81 keV peak, and 1.5 % FWHM for the 356 keV peak. We discuss the importance of detector material with high electron (μτ) e for thick Pixellated detectors

  3. Leakage current measurements on pixelated CdZnTe detectors

    NARCIS (Netherlands)

    Dirks, B.; Blondel, C.; Daly, F.; Gevin, O.; Limousin, O.; Lugiez, F.

    2006-01-01

    In the field of the R&D of a new generation hard X-ray cameras for space applications we focus on the use of pixelated CdTe or CdZnTe semiconductor detectors. They are covered with 64 (0.9×0.9 mm2) or 256 (0.5×0.5 mm2) pixels, surrounded by a guard ring and operate in the energy ranging from several

  4. Leakage current measurements on pixelated CdZnTe detectors

    International Nuclear Information System (INIS)

    Dirks, B.P.F.; Blondel, C.; Daly, F.; Gevin, O.; Limousin, O.; Lugiez, F.

    2006-01-01

    In the field of the R and D of a new generation hard X-ray cameras for space applications we focus on the use of pixelated CdTe or CdZnTe semiconductor detectors. They are covered with 64 (0.9x0.9 mm 2 ) or 256 (0.5x0.5 mm 2 ) pixels, surrounded by a guard ring and operate in the energy ranging from several keV to 1 MeV, at temperatures between -20 and +20 o C. A critical parameter in the characterisation of these detectors is the leakage current per pixel under polarisation (∼50-500 V/mm). In operation mode each pixel will be read-out by an integrated spectroscopy channel of the multi-channel IDeF-X ASIC currently developed in our lab. The design and functionality of the ASIC depends directly on the direction and value of the current. A dedicated and highly insulating electronics circuit is designed to automatically measure the current in each individual pixel, which is in the order of tens of pico-amperes. Leakage current maps of different CdZnTe detectors of 2 and 6 mm thick and at various temperatures are presented and discussed. Defect density diagnostics have been performed by calculation of the activation energy of the material

  5. 3-D Spatial Resolution of 350 μm Pitch Pixelated CdZnTe Detectors for Imaging Applications.

    Science.gov (United States)

    Yin, Yongzhi; Chen, Ximeng; Wu, Heyu; Komarov, Sergey; Garson, Alfred; Li, Qiang; Guo, Qingzhen; Krawczynski, Henric; Meng, Ling-Jian; Tai, Yuan-Chuan

    2013-02-01

    We are currently investigating the feasibility of using highly pixelated Cadmium Zinc Telluride (CdZnTe) detectors for sub-500 μ m resolution PET imaging applications. A 20 mm × 20 mm × 5 mm CdZnTe substrate was fabricated with 350 μ m pitch pixels (250 μ m anode pixels with 100 μ m gap) and coplanar cathode. Charge sharing among the pixels of a 350 μ m pitch detector was studied using collimated 122 keV and 511 keV gamma ray sources. For a 350 μ m pitch CdZnTe detector, scatter plots of the charge signal of two neighboring pixels clearly show more charge sharing when the collimated beam hits the gap between adjacent pixels. Using collimated Co-57 and Ge-68 sources, we measured the count profiles and estimated the intrinsic spatial resolution of 350 μ m pitch detector biased at -1000 V. Depth of interaction was analyzed based on two methods, i.e., cathode/anode ratio and electron drift time, in both 122 keV and 511 keV measurements. For single-pixel photopeak events, a linear correlation between cathode/anode ratio and electron drift time was shown, which would be useful for estimating the DOI information and preserving image resolution in CdZnTe PET imaging applications.

  6. Gas filled prototype of a CdZnTe pixel detector

    International Nuclear Information System (INIS)

    Ramsey, B.; Sharma, D.; Sipila, H.; Gostilo, V.; Loupilov, A.

    2001-01-01

    CdZnTe pixel structures are currently the most promising detectors for the focal planes of hard X-ray telescopes, for astronomical observation in the range 5-100 keV. In Sharma et al. (Proc. SPIE 3765 (1999) 822) and Ramsey et al. (Nucl. Instrum. Methods A 458 (2001) 55) we presented preliminary results on the development of prototype 4x4 CdZnTe imaging detectors operated under vacuum. These pixel detectors were installed inside vacuum chambers on three-stage Peltier coolers providing detector temperatures down to -40 deg. C. A miniature sputter ion pump inside each chamber maintained the necessary vacuum of 10 -5 Torr. At a temperature of -20 deg. C we achieved an FWHM energy resolution of between 2% and 3% at 60 keV and ∼15% at 5.9 keV; however, the dependency on temperature was weak and at +20 deg. C the respective resolutions were 3% and 20%. As the detectors could be operated at room temperature without loss of their good characteristics it was possible to exclude the sputter ion pump and fill the chamber with dry nitrogen instead. We have tested a nitrogen-filled CdZnTe (5x5x1 mm 3 ) prototype having 0.65x0.65 mm 2 readout pads on a 0.75 mm pitch. The interpixel resistance at an applied voltage of 10 V was higher than 50 GΩ and the pixel leakage currents at room temperature with a bias of 200 V between each pad and the common electrode did not exceed 0.8 nA. The pixel detector inside the microassembly, which also contained the input stages of the preamplifiers, was installed on a Peltier cooler to maintain the detector temperature at +20 deg. C. To define real leakage currents of the pixels in their switched-on state we have checked the voltage on the preamplifiers feedback resistors. The resulting currents were 10-50 pA at a detector bias of 500 V. Under test, the typical energy resolution per pixel at +20 deg. C was ∼3% at energy 59.6 keV and ∼20% at energy 5.9 keV, which are similar to the values obtained in the vacuum prototype at room temperature

  7. X-Ray Beam Studies of Charge Sharing in Small Pixel, Spectroscopic, CdZnTe Detectors

    Science.gov (United States)

    Allwork, Christopher; Kitou, Dimitris; Chaudhuri, Sandeep; Sellin, Paul J.; Seller, Paul; Veale, Matthew C.; Tartoni, Nicola; Veeramani, Perumal

    2012-08-01

    Recent advances in the growth of CdZnTe material have allowed the development of small pixel, spectroscopic, X-ray imaging detectors. These detectors have applications in a diverse range of fields such as medical, security and industrial sectors. As the size of the pixels decreases relative to the detector thickness, the probability that charge is shared between multiple pixels increases due to the non zero width of the charge clouds drifting through the detector. These charge sharing events will result in a degradation of the spectroscopic performance of detectors and must be considered when analyzing the detector response. In this paper charge sharing and charge loss in a 250 μm pitch CdZnTe pixel detector has been investigated using a mono-chromatic X-ray beam at the Diamond Light Source, U.K. Using a 20 μm beam diameter the detector response has been mapped for X-ray energies both above (40 keV) and below (26 keV) the material K-shell absorption energies to study charge sharing and the role of fluorescence X-rays in these events.

  8. Characterization of a large-format, fine-pitch CdZnTe pixel detector for the HEFT balloon-Borne experiment

    OpenAIRE

    Chen, C. M. Hubert; Cook, Walter R.; Harrison, Fiona A.; Lin, Jiao Y. Y.

    2004-01-01

    We have developed a large-format CdZnTe pixel detector with custom, low-noise ASIC readout, for astrophysical applications. In particular, this detector is targeted for use in the High-Energy Focusing Telescope (HEFT), a balloon-borne experiment with focusing optics for 20-70 keV. The detector is a 24 X 44 pixel array of 498-µm pitch. As a focal plane detector, uniformity from pixel to pixel is very desirable. In this paper, we present the characterization of some detector properties for the ...

  9. Charge loss between contacts of CdZnTe pixel detectors

    International Nuclear Information System (INIS)

    Bolotnikov, A.E.; Cook, W.R.; Harrison, F.A.; Wong, A.-S.; Schindler, S.M.; Eichelberger, A.C.

    1999-01-01

    The surface of Cd 1-x Zn x Te (CZT) material has high resistivity but is not a perfect dielectric. Even a small surface conductivity can affect the electric field distribution, and therefore, the charge collection efficiency of a CZT pixel detector. The paper describes studies of this phenomenon for several contact configurations made on a single CZT detector. We have determined the maximum inter-contact separation at which the surface inter-pixel charge loss can be neglected. (author)

  10. Performance comparison of small-pixel CdZnTe radiation detectors with gold contacts formed by sputter and electroless deposition

    Science.gov (United States)

    Bell, S. J.; Baker, M. A.; Duarte, D. D.; Schneider, A.; Seller, P.; Sellin, P. J.; Veale, M. C.; Wilson, M. D.

    2017-06-01

    Recent improvements in the growth of wide-bandgap semiconductors, such as cadmium zinc telluride (CdZnTe or CZT), has enabled spectroscopic X/γ-ray imaging detectors to be developed. These detectors have applications covering homeland security, industrial analysis, space science and medical imaging. At the Rutherford Appleton Laboratory (RAL) a promising range of spectroscopic, position sensitive, small-pixel Cd(Zn)Te detectors have been developed. The challenge now is to improve the quality of metal contacts on CdZnTe in order to meet the demanding energy and spatial resolution requirements of these applications. The choice of metal deposition method and fabrication process are of fundamental importance. Presented is a comparison of two CdZnTe detectors with contacts formed by sputter and electroless deposition. The detectors were fabricated with a 74 × 74 array of 200 μm pixels on a 250 μm pitch and bump-bonded to the HEXITEC ASIC. The X/γ-ray emissions from an 241Am source were measured to form energy spectra for comparison. It was found that the detector with contacts formed by electroless deposition produced the best uniformity and energy resolution; the best pixel produced a FWHM of 560 eV at 59.54 keV and 50% of pixels produced a FWHM better than 1.7 keV . This compared with a FWHM of 1.5 keV for the best pixel and 50% of pixels better than 4.4 keV for the detector with sputtered contacts.

  11. Charge loss between contacts of CdZnTe pixel detectors

    CERN Document Server

    Bolotnikov, A E; Harrison, F A; Wong, A S; Schindler, S M; Eichelberger, A C

    1999-01-01

    The surface of Cd sub 1 sub - sub x Zn sub x Te (CZT) material has high resistivity but is not a perfect dielectric. Even a small surface conductivity can affect the electric field distribution, and therefore, the charge collection efficiency of a CZT pixel detector. The paper describes studies of this phenomenon for several contact configurations made on a single CZT detector. We have determined the maximum inter-contact separation at which the surface inter-pixel charge loss can be neglected. (author)

  12. Effects of bulk and surface conductivity on the performance of CdZnTe pixel detectors

    DEFF Research Database (Denmark)

    Bolotnikov, A.E.; Chen, C.M.H.; Cook, W.R.

    2002-01-01

    , the existence of a thin (10-100 A) oxide layer on the surface of CZT, formed during the fabrication process, affects both bulk and surface leakage currents. We demonstrate that the measured I-V dependencies of bulk current can be explained by considering the CZT detector as a metal-semiconductor-metal system......-collection efficiency in detectors with multicontact geometry; some fraction of the electric field lines that originated on the cathode intersects the surface areas between the pixel contacts where the charge produced by an ionizing particle gets trapped. To overcome this effect, we place a grid of thin electrodes...

  13. Optimal configuration of a low-dose breast-specific gamma camera based on semiconductor CdZnTe pixelated detectors

    Science.gov (United States)

    Genocchi, B.; Pickford Scienti, O.; Darambara, DG

    2017-05-01

    Breast cancer is one of the most frequent tumours in women. During the ‘90s, the introduction of screening programmes allowed the detection of cancer before the palpable stage, reducing its mortality up to 50%. About 50% of the women aged between 30 and 50 years present dense breast parenchyma. This percentage decreases to 30% for women between 50 to 80 years. In these women, mammography has a sensitivity of around 30%, and small tumours are covered by the dense parenchyma and missed in the mammogram. Interestingly, breast-specific gamma-cameras based on semiconductor CdZnTe detectors have shown to be of great interest to early diagnosis. Infact, due to the high energy, spatial resolution, and high sensitivity of CdZnTe, molecular breast imaging has been shown to have a sensitivity of about 90% independently of the breast parenchyma. The aim of this work is to determine the optimal combination of the detector pixel size, hole shape, and collimator material in a low dose dual head breast specific gamma camera based on a CdZnTe pixelated detector at 140 keV, in order to achieve high count rate, and the best possible image spatial resolution. The optimal combination has been studied by modeling the system using the Monte Carlo code GATE. Six different pixel sizes from 0.85 mm to 1.6 mm, two hole shapes, hexagonal and square, and two different collimator materials, lead and tungsten were considered. It was demonstrated that the camera achieved higher count rates, and better signal-to-noise ratio when equipped with square hole, and large pixels (> 1.3 mm). In these configurations, the spatial resolution was worse than using small pixel sizes (< 1.3 mm), but remained under 3.6 mm in all cases.

  14. Fast Neutron Detection Using Pixelated CdZnTe Spectrometers

    Science.gov (United States)

    Streicher, Michael; Goodman, David; Zhu, Yuefeng; Brown, Steven; Kiff, Scott; He, Zhong

    2017-07-01

    Fast neutrons are an important signature of special nuclear materials (SNMs). They have a low natural background rate and readily penetrate high atomic number materials that easily shield gamma-ray signatures. Therefore, they provide a complementary signal to gamma rays for detecting shielded SNM. Scattering kinematics dictate that a large nucleus (such as Cd or Te) will recoil with small kinetic energy after an elastic collision with a fast neutron. Charge carrier recombination and quenching further reduce the recorded energy deposited. Thus, the energy threshold of CdZnTe detectors must be very low in order to sense the small signals from these recoils. In this paper, the threshold was reduced to less than 5 keVee to demonstrate that the 5.9-keV X-ray line from 55Fe could be separated from electronic noise. Elastic scattering neutron interactions were observed as small energy depositions (less than 20 keVee) using digitally sampled pulse waveforms from pixelated CdZnTe detectors. Characteristic gamma-ray lines from inelastic neutron scattering were also observed.

  15. Polarization effect of CdZnTe imaging detector based on high energy γ source

    International Nuclear Information System (INIS)

    Li Miao; Xiao Shali; Wang Xi; Shen Min; Zhang Liuqiang; Cao Yulin; Chen Yuxiao

    2011-01-01

    The inner electric potential distribution of CdZnTe detector was derived by applying poisson equation with the first type boundary condition, and the polarization effect of CdZnTe pixellated detector for imaging 137 Cs γ source was investigated. The results of numerical calculation and experiment indicate that electric potential distribution is mainly influenced by applied bias for low charge density in CdZnTe crystal and, in turn, there is linear relationship between electric potential distribution and applied bias that induces uniform electric field under low irradiated flux. However, the electric potential appears polarization phenomenon, and the electric field in CdZnTe crystal is distorted when CdZnTe detector is under high irradiated flux. Consequently, charge carriers in CdZnTe crystal drift towards the edge pixels of irradiated region, and hence, the shut-off central pixels are surrounded by a ring of low counting pixels. The polarization effect indeed deteriorates the performance of CdZnTe detector severely and the event counts of edge pixels for irradiated region reduce about 70%. (authors)

  16. Design and study of a coplanar grid array CdZnTe detector for improved spatial resolution

    International Nuclear Information System (INIS)

    Ma, Yuedong; Xiao, Shali; Yang, Guoqiang; Zhang, Liuqiang

    2014-01-01

    Coplanar grid (CPG) CdZnTe detectors have been used as gamma-ray spectrometers for years. Comparing with pixelated CdZnTe detectors, CPG CdZnTe detectors have either no or poor spatial resolution, which directly limits its use in imaging applications. To address the issue, a 2×2 CPG array CdZnTe detector with dimensions of 7×7×5 mm 3 was fabricated. Each of the CPG pairs in the detector was moderately shrunk in size and precisely designed to improve the spatial resolution while maintaining good energy resolution, considering the charge loss at the surface between the strips of each CPG pairs. Preliminary measurements were demonstrated at an energy resolution of 2.7–3.9% for the four CPG pairs using 662 keV gamma rays and with a spatial resolution of 3.3 mm, which is the best spatial resolution ever achieved for CPG CdZnTe detectors. The results reveal that the CPG CdZnTe detector can also be applied to imaging applications at a substantially higher spatial resolution. - Highlights: • A novel structure of coplanar grid CdZnTe detector was designed to evaluate the possibility of applying the detector to gamma-ray imaging applications. • The best spatial resolution of coplanar grid CdZnTe detectors ever reported has been achieved, along with good spectroscopic performance. • Depth correction of the energy spectra using a new algorithm is presented

  17. Noise in CdZnTe detectors

    International Nuclear Information System (INIS)

    Luke, P. N.; Amman, M.; Lee, J. S.; Manfredi, P. F.

    2000-01-01

    Noise in CdZnTe devices with different electrode configurations was investigated. Measurements on devices with guard-ring electrode structures showed that surface leakage current does not produce any significant noise. The parallel white noise component of the devices appeared to be generated by the bulk current alone, even though the surface current was substantially higher. This implies that reducing the surface leakage current of a CdZnTe detector may not necessarily result in a significant improvement in noise performance. The noise generated by the bulk current is also observed to be below full shot noise. This partial suppression of shot noise may be the result of Coulomb interaction between carriers or carrier trapping. Devices with coplanar strip electrodes were observed to produce a 1/f noise term at the preamplifier output. Higher levels of this 1/f noise were observed with decreasing gap widths between electrodes. The level of this 1/f noise appeared to be independent of bias voltage and leakage current but was substantially reduced after certain surface treatments

  18. Diamond Pixel Detectors

    International Nuclear Information System (INIS)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Doroshenko, J.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foster, J.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Gobbi, B.; Grim, G.P.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Lander, R.; Logiudice, A.; Lu, R.; Lynne, L.M.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Perera, L.; Pirollo, S.; Plano, R.; Procario, M.; Riester, J.L.; Roe, S.; Rott, C.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Wedenig, R.; Weilhammer, P.; White, C.; Zeuner, W.; Zoeller, M.

    2001-01-01

    Diamond based pixel detectors are a promising radiation-hard technology for use at the LHC. We present first results on a CMS diamond pixel sensor. With a threshold setting of 2000 electrons, an average pixel efficiency of 78% was obtained for normally incident minimum ionizing particles

  19. Diamond Pixel Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Doroshenko, J.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foster, J.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Gobbi, B.; Grim, G.P.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Lander, R.; Logiudice, A.; Lu, R.; Lynne, L.M.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Perera, L. E-mail: perera@physics.rutgers.edu; Pirollo, S.; Plano, R.; Procario, M.; Riester, J.L.; Roe, S.; Rott, C.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Wedenig, R.; Weilhammer, P.; White, C.; Zeuner, W.; Zoeller, M

    2001-06-01

    Diamond based pixel detectors are a promising radiation-hard technology for use at the LHC. We present first results on a CMS diamond pixel sensor. With a threshold setting of 2000 electrons, an average pixel efficiency of 78% was obtained for normally incident minimum ionizing particles.

  20. The ATLAS Pixel Detector

    CERN Document Server

    Huegging, Fabian

    2006-06-26

    The contruction of the ATLAS Pixel Detector which is the innermost layer of the ATLAS tracking system is prgressing well. Because the pixel detector will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability for all parts, combined with a low material budget. The final detector layout, new results from production modules and the status of assembly are presented.

  1. Development of a simplified simulation model for performance characterization of a pixellated CdZnTe multimodality imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, P; Santos, A [Departamento de IngenierIa Electronica, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Darambara, D G [Joint Department of Physics, Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, Fulham Road, London SW3 6JJ (United Kingdom)], E-mail: pguerra@die.um.es

    2008-02-21

    Current requirements of molecular imaging lead to the complete integration of complementary modalities in a single hybrid imaging system to correlate function and structure. Among the various existing detector technologies, which can be implemented to integrate nuclear modalities (PET and/or single-photon emission computed tomography with x-rays (CT) and most probably with MR, pixellated wide bandgap room temperature semiconductor detectors, such as CdZnTe and/or CdTe, are promising candidates. This paper deals with the development of a simplified simulation model for pixellated semiconductor radiation detectors, as a first step towards the performance characterization of a multimodality imaging system based on CdZnTe. In particular, this work presents a simple computational model, based on a 1D approximate solution of the Schockley-Ramo theorem, and its integration into the Geant4 application for tomographic emission (GATE) platform in order to perform accurately and, therefore, improve the simulations of pixellated detectors in different configurations with a simultaneous cathode and anode pixel readout. The model presented here is successfully validated against an existing detailed finite element simulator, the multi-geometry simulation code, with respect to the charge induced at the anode, taking into consideration interpixel charge sharing and crosstalk, and to the detector charge induction efficiency. As a final point, the model provides estimated energy spectra and time resolution for {sup 57}Co and {sup 18}F sources obtained with the GATE code after the incorporation of the proposed model.

  2. CdZnTe Image Detectors for Hard-X-Ray Telescopes

    Science.gov (United States)

    Chen, C. M. Hubert; Cook, Walter R.; Harrison, Fiona A.; Lin, Jiao Y. Y.; Mao, Peter H.; Schindler, Stephen M.

    2005-01-01

    Arrays of CdZnTe photodetectors and associated electronic circuitry have been built and tested in a continuing effort to develop focal-plane image sensor systems for hard-x-ray telescopes. Each array contains 24 by 44 pixels at a pitch of 498 m. The detector designs are optimized to obtain low power demand with high spectral resolution in the photon- energy range of 5 to 100 keV. More precisely, each detector array is a hybrid of a CdZnTe photodetector array and an application-specific integrated circuit (ASIC) containing an array of amplifiers in the same pixel pattern as that of the detectors. The array is fabricated on a single crystal of CdZnTe having dimensions of 23.6 by 12.9 by 2 mm. The detector-array cathode is a monolithic platinum contact. On the anode plane, the contact metal is patterned into the aforementioned pixel array, surrounded by a guard ring that is 1 mm wide on three sides and is 0.1 mm wide on the fourth side so that two such detector arrays can be placed side-by-side to form a roughly square sensor area with minimal dead area between them. Figure 1 shows two anode patterns. One pattern features larger pixel anode contacts, with a 30-m gap between them. The other pattern features smaller pixel anode contacts plus a contact for a shaping electrode in the form of a grid that separates all the pixels. In operation, the grid is held at a potential intermediate between the cathode and anode potentials to steer electric charges toward the anode in order to reduce the loss of charges in the inter-anode gaps. The CdZnTe photodetector array is mechanically and electrically connected to the ASIC (see Figure 2), either by use of indium bump bonds or by use of conductive epoxy bumps on the CdZnTe array joined to gold bumps on the ASIC. Hence, the output of each pixel detector is fed to its own amplifier chain.

  3. Investigation of the limitations of the highly pixilated CdZnTe detector for PET applications.

    Science.gov (United States)

    Komarov, Sergey; Yin, Yongzhi; Wu, Heyu; Wen, Jie; Krawczynski, Henric; Meng, Ling-Jian; Tai, Yuan-Chuan

    2012-11-21

    We are investigating the feasibility of a high resolution positron emission tomography (PET) insert device based on the CdZnTe detector with 350 µm anode pixel pitch to be integrated into a conventional animal PET scanner to improve its image resolution. In this paper, we have used a simplified version of the multi pixel CdZnTe planar detector, 5 mm thick with 9 anode pixels only. This simplified 9 anode pixel structure makes it possible to carry out experiments without a complete application-specific integrated circuits readout system that is still under development. Special attention was paid to the double pixel (or charge sharing) detections. The following characteristics were obtained in experiment: energy resolution full-width-at-half-maximum (FWHM) is 7% for single pixel and 9% for double pixel photoelectric detections of 511 keV gammas; timing resolution (FWHM) from the anode signals is 30 ns for single pixel and 35 ns for double pixel detections (for photoelectric interactions only the corresponding values are 20 and 25 ns); position resolution is 350 µm in x,y-plane and ∼0.4 mm in depth-of-interaction. The experimental measurements were accompanied by Monte Carlo (MC) simulations to find a limitation imposed by spatial charge distribution. Results from MC simulations suggest the limitation of the intrinsic spatial resolution of the CdZnTe detector for 511 keV photoelectric interactions is 170 µm. The interpixel interpolation cannot recover the resolution beyond the limit mentioned above for photoelectric interactions. However, it is possible to achieve higher spatial resolution using interpolation for Compton scattered events. Energy and timing resolution of the proposed 350 µm anode pixel pitch detector is no better than 0.6% FWHM at 511 keV, and 2 ns FWHM, respectively. These MC results should be used as a guide to understand the performance limits of the pixelated CdZnTe detector due to the underlying detection processes, with the understanding of

  4. Pixel detector readout chip

    CERN Multimedia

    1991-01-01

    Close-up of a pixel detector readout chip. The photograph shows an aera of 1 mm x 2 mm containing 12 separate readout channels. The entire chip contains 1000 readout channels (around 80 000 transistors) covering a sensitive area of 8 mm x 5 mm. The chip has been mounted on a silicon detector to detect high energy particles.

  5. Characterization of CdZnTe ambient temperature detectors

    International Nuclear Information System (INIS)

    Lavietes, A.

    1994-09-01

    A great deal of interest has been generated in the use of cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) detectors for ambient temperature detection of radionuclides. The addition of zinc to CdTe provides several benefits that enhance the materials operational characteristics at ambient temperature. Recent movement in the industry is to produce larger volume detectors using CdZnTe without much known about the effects of larger geometry on performance. The purpose of this study is to get an idea of the relationship of detector performance to both area and thickness variations

  6. ATLAS ITk Pixel detector

    CERN Document Server

    Gemme, Claudia; The ATLAS collaboration

    2016-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

  7. CMS Pixel Detector Upgrade

    CERN Document Server

    INSPIRE-00038772

    2011-01-01

    The present Compact Muon Solenoid silicon pixel tracking system has been designed for a peak luminosity of 1034cm-2s-1 and total dose corresponding to two years of the Large Hadron Collider (LHC) operation. With the steady increase of the luminosity expected at the LHC, a new pixel detector with four barrel layers and three endcap disks is being designed. We will present the key points of the design: the new geometry, which minimizes the material budget and increases the tracking points, and the development of a fast digital readout architecture, which ensures readout efficiency even at high rate. The expected performances for tracking and vertexing of the new pixel detector are also addressed.

  8. ATLAS Pixel Detector Upgrade

    CERN Document Server

    Flick, T; The ATLAS collaboration

    2009-01-01

    The first upgrade for higher luminosity at LHC for the ATLAS pixel detector is the insertion of a forth layer, the IBL. The talk gives an overview about what the IBL is and how it will be set up, as well as to give a status of the research and develoment work.

  9. ALICE Silicon Pixel Detector

    CERN Multimedia

    Manzari, V

    2013-01-01

    The Silicon Pixel Detector (SPD) forms the innermost two layers of the 6-layer barrel Inner Tracking System (ITS). The SPD plays a key role in the determination of the position of the primary collision and in the reconstruction of the secondary vertices from particle decays.

  10. Exploration of Pixelated detectors for double beta decay searches within the COBRA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schwenke, M., E-mail: schwenke@asp.tu-dresden.de [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, Zellescher Weg 19, 01069 Dresden (Germany); Zuber, K.; Janutta, B. [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, Zellescher Weg 19, 01069 Dresden (Germany); He, Z.; Zeng, F. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109-2104 (United States); Anton, G.; Michel, T.; Durst, J.; Lueck, F.; Gleixner, T. [Erlangen Centre for Astroparticle Physics, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany); Goessling, C.; Schulz, O.; Koettig, T. [Technische Universitaet Dortmund, Physik E IV, 44221 Dortmund (Germany); Krawczynski, H.; Martin, J. [Department of Physics, Washington University in St. Louis, Campus Box 1105, One Brookings Drive, St. Louis, MO 63130-4899 (United States); Stekl, I.; Cermak, P. [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, 128 00 Prague (Czech Republic)

    2011-09-11

    The aim of the COBRA experiment is the search for neutrinoless double beta decay events in Cadmium Zinc Telluride (CdZnTe) room temperature semiconductor detectors. The development of pixelated detectors provides the potential for clear event identification and thus major background reduction. The tracking option of a semiconductor is a unique approach in this field. For initial studies, several possible detector systems are considered with a special regard for low background applications: the large volume system Polaris with a pixelated CdZnTe sensor, Timepix detectors with Si and enriched CdTe sensor material and a CdZnTe pixel system developed at the Washington University in St. Louis, USA. For all detector systems first experimental background measurements taken at underground laboratories (Gran Sasso Underground Laboratory in Italy, LNGS and the Niederniveau Messlabor Felsenkeller in Dresden, Germany) and additionally for the Timepix detectors simulation results are presented.

  11. Gas pixel detectors

    International Nuclear Information System (INIS)

    Bellazzini, R.; Baldini, L.; Brez, A.; Cavalca, F.; Latronico, L.; Massai, M.M.; Minuti, M.; Omodei, N.; Pesce-Rollins, M.; Sgro, C.; Spandre, G.; Costa, E.; Soffitta, P.

    2007-01-01

    With the Gas Pixel Detector (GPD), the class of micro-pattern gas detectors has reached a complete integration between the gas amplification structure and the read-out electronics. To obtain this goal, three generations of application-specific integrated circuit of increased complexity and improved functionality has been designed and fabricated in deep sub-micron CMOS technology. This implementation has allowed manufacturing a monolithic device, which realizes, at the same time, the pixelized charge-collecting electrode and the amplifying, shaping and charge measuring front-end electronics of a GPD. A big step forward in terms of size and performances has been obtained in the last version of the 0.18 μm CMOS analog chip, where over a large active area of 15x15 mm 2 a very high channel density (470 pixels/mm 2 ) has been reached. On the top metal layer of the chip, 105,600 hexagonal pixels at 50 μm pitch have been patterned. The chip has customable self-trigger capability and includes a signal pre-processing function for the automatic localization of the event coordinates. In this way, by limiting the output signal to only those pixels belonging to the region of interest, it is possible to reduce significantly the read-out time and data volume. In-depth tests performed on a GPD built up by coupling this device to a fine pitch (50 μm) gas electron multiplier are reported. Matching of the gas amplification and read-out pitch has let to obtain optimal results. A possible application of this detector for X-ray polarimetry of astronomical sources is discussed

  12. Infrared Illuminated CdZnTe detectors with improved performance

    International Nuclear Information System (INIS)

    Ivanov, V.; Loutchanski, A.; Dorogov, P.; Khinoverov, S.

    2013-06-01

    It was found that IR illumination of a properly chosen wavelength and intensity can significantly improve spectrometric characteristics of CdZnTe quasi-hemispherical detectors [1]. Improving of the spectrometric characteristics is due to improvement of uniformity of charge collection by the detector volume. For operation at room temperature the optimal wavelength of IR illumination is about 940 nm, but for operation at lower temperature of -20 deg. C the optimal wavelengths of IR illumination is about 1050 nm. Infrared illumination can be performed using conventional low-power IR LEDs. Application of SMD LEDs allows produce miniature detection probes with IR illuminated CdZnTe detectors. We have fabricated and tested a variety of detection probes with CdZnTe quasi-hemispherical detectors from the smallest with volumes of 1-5 mm 3 to larger with volumes of 1.5 cm 3 and 4.0 cm 3 . The use of IR illumination significantly improves spectrometric characteristics of the probes operating at room temperature, especially probes with detectors of large volumes. The probe with the detector of 4 cm 3 without IR illumination had energy resolution of 24.2 keV at 662 keV and of 12.5 keV with IR illumination. (authors)

  13. ATLAS Pixel Detector Operational Experience

    CERN Document Server

    Di Girolamo, B; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.9% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  14. Direct conversion Si and CdZnTe detectors for digital mammography

    CERN Document Server

    Yin Shi Shi; Maeding, D; Mainprize, J; Mawdsley, G; Yaffe, M J; Gordon, E E; Hamilton, W J

    2000-01-01

    Hybrid pixel detector arrays that convert X-rays directly into charge signals are under development at NOVA for application to digital mammography. This technology also has wide application possibilities in other fields of radiology or in industrial imaging, nondestructive evaluation (NDE) and nondestructive inspection (NDI). These detectors have potentially superior properties compared to either emulsion-based film-screen systems which has nonlinear response to X-rays, or phosphor-based detectors in which there is an intermediate step of X-ray to light photon conversion (Feig and Yaffe, Radiol. Clinics North America 33 (1995) 1205-1230). Potential advantages of direct conversion detectors are high quantum efficiencies (QE) of 98% or higher (for 0.3 mm thick CdZnTe detector with 20 keV X-rays), improved contrast, high sensitivity and low intrinsic noise. These factors are expected to contribute to high detective quantum efficiency (DQE). The prototype hybrid pixel detector developed has 50x50 mu m pixel size,...

  15. Performance updating of CdZnTe strip-drift detectors

    DEFF Research Database (Denmark)

    Shorohov, M.; Tsirkunova, I.; Loupilov, A.

    2007-01-01

    59.6 and 662 keV correspondingly. Recently, significant progress was done in CdZnTe crystals growth technology. In the present paper we present preliminary result of performance updating of CdZnTe strip-drift detectors based on crystal of 10 x 10 x 6 mm 3 produced by Yinnel Tech company. Results...

  16. Performance simulation and structure design of Binode CdZnTe gamma-ray detector

    International Nuclear Information System (INIS)

    Niu Libo; Li Yulan; Fu Jianqiang; Jiang Hao; Zhang Lan; He Bin; Li Yuanjing

    2014-01-01

    A new electrode structure CdZnTe (Cadmium Zinc Telluride) detector named Binode CdZnTe has been pro- posed in this paper. Together with the softwares of MAXWELL, GEANT4, and ROOT, the charge collection process and its gamma spectrum of the detector have been simulated and the detector structure has been optimized. In order to improve its performance further, Compton scattering effect correction has been used. The simulation results demonstrate that with refined design and Compton scattering effect correction, Binode CdZnTe detectors is capable of achieving 3.92% FWHM at 122 keV, and 1.27% FWHM at 662 keV. Com- pared with other single-polarity (electron-only) detector configurations, Binode CdZnTe detector offers a cost effective and simple structure alternative with comparable energy resolution. (authors)

  17. CMS Barrel Pixel Detector Overview

    CERN Document Server

    Kästli, H C; Erdmann, W; Gabathuler, K; Hörmann, C; Horisberger, Roland Paul; König, S; Kotlinski, D; Meier, B; Robmann, P; Rohe, T; Streuli, S

    2007-01-01

    The pixel detector is the innermost tracking device of the CMS experiment at the LHC. It is built from two independent sub devices, the pixel barrel and the end disks. The barrel consists of three concentric layers around the beam pipe with mean radii of 4.4, 7.3 and 10.2 cm. There are two end disks on each side of the interaction point at 34.5 cm and 46.5 cm. This article gives an overview of the pixel barrel detector, its mechanical support structure, electronics components, services and its expected performance.

  18. The ALICE Pixel Detector

    International Nuclear Information System (INIS)

    Mercado-Perez, Jorge

    2002-01-01

    The present document is a brief summary of the performed activities during the 2001 Summer Student Programme at CERN under the Scientific Summer at Foreign Laboratories Program organized by the Particles and Fields Division of the Mexican Physical Society (Sociedad Mexicana de Fisica). In this case, the activities were related with the ALICE Pixel Group of the EP-AIT Division, under the supervision of Jeroen van Hunen, research fellow in this group. First, I give an introduction and overview to the ALICE experiment; followed by a description of wafer probing. A brief summary of the test beam that we had from July 13th to July 25th is given as well

  19. Ground calibration of the spatial response and quantum efficiency of the CdZnTe hard x-ray detectors for NuSTAR

    Science.gov (United States)

    Grefenstette, Brian W.; Bhalerao, Varun; Cook, W. Rick; Harrison, Fiona A.; Kitaguchi, Takao; Madsen, Kristin K.; Mao, Peter H.; Miyasaka, Hiromasa; Rana, Vikram

    2017-08-01

    Pixelated Cadmium Zinc Telluride (CdZnTe) detectors are currently flying on the Nuclear Spectroscopic Telescope ARray (NuSTAR) NASA Astrophysics Small Explorer. While the pixel pitch of the detectors is ≍ 605 μm, we can leverage the detector readout architecture to determine the interaction location of an individual photon to much higher spatial accuracy. The sub-pixel spatial location allows us to finely oversample the point spread function of the optics and reduces imaging artifacts due to pixelation. In this paper we demonstrate how the sub-pixel information is obtained, how the detectors were calibrated, and provide ground verification of the quantum efficiency of our Monte Carlo model of the detector response.

  20. The ALICE pixel detector

    CERN Document Server

    Mercado Perez, J

    2002-01-01

    The present document is a brief summary of the performed activities during the 2001 Summer Student Programme at CERN under the Scientific Summer at Foreign Laboratories Program organized by the Particles and Fields Division of the Mexican Physical Society (Sociedad Mexicana de Fisica). In this case, the activities were related with the ALICE Pixel Group of the EP-AIT Division, under the supervision of Jeroen van Hunen, research fellow in this group. First, I give an introduction and overview to the ALICE experiment; followed by a description of wafer probing. A brief summary of the test beam that we had from July 13th to July 25th is given as well. (3 refs).

  1. Cooled CdZnTe detectors for X-ray astronomy

    CERN Document Server

    Bale, G; Seller, P; Lowe, B

    1999-01-01

    Recent results combining thermoelectrically cooled CdZnTe detectors with a low-noise Pentafet preamplifier are presented. Cooling between -30 deg. C and -40 deg. C reduces the leakage current of the detectors and allows the use of a pulsed reset preamplifier and long shaping times, significantly improving the energy resolution. Mn K subalpha X-rays at 5.9 keV have been observed with a resolution of less than 280 eV FWHM and a peak to background of more than 200:1. The Fano factor of the material has been estimated at 0.11+-0.012 at -40 deg. C. The detector requirement for X-ray astronomy will be a photon-counting imaging spectrometer. A 16x16 element, bump bonded pixel detector is described and results from a prototype silicon array presented. The detector is constructed with ASIC amplifiers with a system noise of <25 electrons rms and should give an energy resolution comparable to the Pentafet results presented here.

  2. The FPGA Pixel Array Detector

    International Nuclear Information System (INIS)

    Hromalik, Marianne S.; Green, Katherine S.; Philipp, Hugh T.; Tate, Mark W.; Gruner, Sol M.

    2013-01-01

    A proposed design for a reconfigurable x-ray Pixel Array Detector (PAD) is described. It operates by integrating a high-end commercial field programmable gate array (FPGA) into a 3-layer device along with a high-resistivity diode detection layer and a custom, application-specific integrated circuit (ASIC) layer. The ASIC layer contains an energy-discriminating photon-counting front end with photon hits streamed directly to the FPGA via a massively parallel, high-speed data connection. FPGA resources can be allocated to perform user defined tasks on the pixel data streams, including the implementation of a direct time autocorrelation function (ACF) with time resolution down to 100 ns. Using the FPGA at the front end to calculate the ACF reduces the required data transfer rate by several orders of magnitude when compared to a fast framing detector. The FPGA-ASIC high-speed interface, as well as the in-FPGA implementation of a real-time ACF for x-ray photon correlation spectroscopy experiments has been designed and simulated. A 16×16 pixel prototype of the ASIC has been fabricated and is being tested. -- Highlights: ► We describe the novelty and need for the FPGA Pixel Array Detector. ► We describe the specifications and design of the Diode, ASIC and FPGA layers. ► We highlight the Autocorrelation Function (ACF) for speckle as an example application. ► Simulated FPGA output calculates the ACF for different input bitstreams to 100 ns. ► Reduced data transfer rate by 640× and sped up real-time ACF by 100× other methods.

  3. STAR PIXEL detector mechanical design

    Energy Technology Data Exchange (ETDEWEB)

    Wieman, H H; Anderssen, E; Greiner, L; Matis, H S; Ritter, H G; Sun, X; Szelezniak, M [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)], E-mail: hhwieman@lbl.gov

    2009-05-15

    A high resolution pixel detector is being designed for the STAR [1] experiment at RHIC. This device will use MAPS as the detector element and will have a pointing accuracy of {approx}25 microns. We will be reporting on the mechanical design required to support this resolution. The radiation length of the first layer ({approx}0.3% X{sub 0}) and its distance from the interaction point (2.5 cm) determines the resolution. The design makes use of air cooling and thin carbon composite structures to limit the radiation length. The mechanics are being developed to achieve spatial calibrations and stability to 20 microns and to permit rapid detector replacement in event of radiation damage or other potential failures from operation near the beam.

  4. Operational Experience with the ATLAS Pixel Detector

    CERN Document Server

    Djama, Fares; The ATLAS collaboration

    2017-01-01

    Run 2 of the LHC collider sets new challenges to track and vertex reconstruction because of its higher energy, pileup and luminosity. The ATLAS tracking performance relies critically on the Pixel Detector. Therefore, in view of Run 2, the ATLAS collaboration has constructed the first 4-layer pixel detector in Particle Physics by installing a new pixel layer, called Insertable B-Layer (IBL). Operational experience and performance of the 4-layer Pixel Detector during Run 2 are presented.

  5. Performance of CdZnTe coplanar-grid gamma-ray detectors

    International Nuclear Information System (INIS)

    Luke, P.N.; Eissler, E.E.

    1995-11-01

    CdZnTe crystals grown using the high-pressure Bridgman method exhibit many properties that are desirable for radiation detector fabrication, such as high resistivity, stable operation, relative ease of processing, and the availability of large volume crystals. However, as is common with other compound semi-conductor materials, currently available CdZnTe crystals have poor charge transport characteristics. This seriously the spectral performance of detectors, especially in gamma-ray detection. The coplanar-grid detection technique was recently developed to address such charge collection problems. This technique was first demonstrated using a 5 mm cube CdZnTe detector, and a dramatic improvement in spectral response has been achieved. These early results verified the effectiveness of this technique and suggested that large-volume gamma-ray detectors with high energy resolution can be realized. To further the development of such detectors, it is important to understand the various factors that affect detector performance. The purpose of this paper is to examine the effects of material properties on the spectral performance of CdZnTe coplanar-grid detectors. Theoretical spectral response is to show the level of performance that can be achieved given the typical carrier mobility-lifetime (μτ) properties of present-day materials. Nonuniformity in the charge transport properties of the material, which could limit the energy resolution of the detectors, has been studied experimentally and some of the results are presented here

  6. Performance Evaluation of New Generation CdZnTe Detectors for Safeguards Applications

    International Nuclear Information System (INIS)

    Ivanovs, V.; Mintcheva, J.; Berlizov, A.; Lebrun, A.

    2015-01-01

    Cadmium zinc telluride detectors (CdZnTe) have found a wide application in nondestructive assay measurements in the IAEA's verification practice. It is because of their form factor, usability, sensitivity and good spectral characteristics that they are extensively used for fresh and spent fuel attribute test measurements. Until now, the series of CdZnTe detectors utilized in the IAEA have covered the range of 5 mm 3 , 20 mm 3 , 60 mm 3 and 500mm 3 of sensitive volume. Recently, new CdZnTe detectors with improved spectroscopic characteristics and significantly bigger active volume have become available, owing to advances in crystal and detector manufacturing and signal processing technologies. The distinctive feature of this new technological development is the application of a low-intensity monochromatic optical stimulation with infrared (IR) light. The use of IR illumination with a properly chosen wavelength close to the absorption edge of the CdZnTe can significantly improve the performance of the detectors. Recognizing potential benefits of these detectors in safeguards applications, the IAEA has performed an evaluation of their performance characteristics. Under evaluation were several new detectors with sensitive volumes of 500 mm 3 , 1500 mm 3 and 4000 mm 3 , as well as all-in-one 60 mm 3 , 500 mm 3 and 1500 mm 3 integrated micro-spectrometers available from RITEC, Latvia. In addition to the standard performance characteristics, such as energy resolution, peak shape, efficiency, linearity, throughput and temperature stability, the potential use of the detectors for safeguards specific measurements, such as uranium enrichment with infinite thickness method, was of particular interest. The paper will describe the advances in the CdZnTe detector technology and present the results of their performance evaluation. (author)

  7. Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, P.H., E-mail: pinghe.lu@redlen.com; Gomolchuk, P.; Chen, H.; Beitz, D.; Grosser, A.W.

    2015-06-01

    This paper described improvements in the ruggedization of CdZnTe detectors and detector assemblies for use in radiation detection applications. Research included experimenting with various conductive and underfill adhesive material systems suitable for CZT substrates. A detector design with encapsulation patterning was developed to protect detector surfaces and to control spacing between CZT anode and PCB carrier. Robustness of bare detectors was evaluated through temperature cycling and metallization shear testing. Attachment processes using well-chosen adhesives and PCB carrier materials were optimized to improve reliability of detector assemblies, resulted in Improved Attachment Detector Assembly. These detector assemblies were subjected to aggressive temperature cycling, and varying levels of drop/shock and vibration, in accordance with modified JEDEC, ANSI and FedEx testing standards, to assess their ruggedness. Further enhanced detector assembly ruggedization methods were investigated involving adhesive conformal coating, potting and dam filling on detector assemblies, which resulted in the Enhanced Ruggedization Detector Assembly. Large numbers of CZT detectors and detector assemblies with 5 mm and 15 mm thick, over 200 in total, were tested. Their performance was evaluated by exposure to various radioactive sources using comprehensive predefined detector specifications and testing protocols. Detector assemblies from improved attachment and enhanced ruggedization showed stable performances during the harsh environmental condition tests. In conclusion, significant progress has been made in improving the reliability and enhancing the ruggedness of CZT detector assemblies for radiation detection applications deployed in operational environments. - Highlights: • We developed ruggedization methods to enhance reliability of CZT detector assemblies. • Attachment of CZT radiation detectors was improved through comparative studies. • Bare detector metallization

  8. Study and modelling of the new generation Cd(Zn)Te X and gamma-ray detectors for space applications

    International Nuclear Information System (INIS)

    Dirks, Bob-Petrus-Franciscus

    2006-01-01

    The scientific astrophysics community needs a new instrument to gain more insight in the origin of the cosmic X-ray background, the physics of black holes and particle acceleration mechanisms in the energy range between 0.5 to 80 keV. Existing instruments like Chandra and XMM-Newton show very good results up to ∼10 keV but lack sufficient sensitivity above this value. In order to keep or improve the same performances up to ∼80 keV, grazing incidence mirrors with a large focal length of at least 20 m should be used. Since satellites this big cannot be launched with existing launchers, the mirror and detector must be placed on two different satellites flying in formation. The Simbol-X space mission will be the first project of this type. A high sensitivity at 80 keV requires not only a long focal length but also a detection unit with high spatial resolution, using detectors that are still efficient at these relatively high energies. CEA/Saclay/DAPNIA is developing this crucial element for the Simbol-X space mission. The imager consists of several modules, each built from individual X-ray mini-cameras. A single camera is a hybridisation of custom read-out electronics connected to a Cd(Zn)Te semiconductor crystal. The ensemble must be able to efficiently detect photons of up to 80 keV with an energy resolution of ∼1.3 keV (FWHM) at 68 keV. Furthermore it must be equipped with small pixels (∼500*500 μm"2) to attain the desired spatial resolution of 15 arcsec. In order to reach a good sensitivity and energy resolution, ultra-low noise read-out electronics in combination with high-quality semiconductor crystals are mandatory. The read-out electronics, baptised IDeF-X (Imaging Detector Front-end for X-rays), is also developed by CEA/Saclay. A thorough understanding of its functioning as well as its testing forms a part of this work. The spectroscopic performance of the detector is directly related to the electronics noise. The noise characteristics of the ASIC are

  9. High performance p-i-n CdTe and CdZnTe detectors

    CERN Document Server

    Khusainov, A K; Ilves, A G; Morozov, V F; Pustovoit, A K; Arlt, R D

    1999-01-01

    A breakthrough in the performance of p-i-n CdTe and CdZnTe detectors is reported. The detector stability has been significantly improved, allowing their use in precise gamma and XRF applications. Detectors with energy resolution close to Si and Ge were produced operating with only -30--35 deg. C cooling (by a Peltier cooler of 15x15x10 mm size and a consumed power less than 5 W). Presently detectors with volume of up to 300 mm sup 3 are available. In terms of photoelectric effect efficiency it corresponds to HPGe detectors with volumes of about 1.5 cm sup 3. The possibilities of further improvement of CdTe and CdZnTe detector characteristics are discussed in this paper.

  10. Operational experience of the ATLAS Pixel detector

    CERN Document Server

    Hirschbuehl, D; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  11. Operational experience of the ATLAS Pixel Detector

    CERN Document Server

    Marcisovsky, M; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  12. The ALICE Silicon Pixel Detector System (SPD)

    CERN Document Server

    Kluge, A; Antinori, Federico; Burns, M; Cali, I A; Campbell, M; Caselle, M; Ceresa, S; Dima, R; Elias, D; Fabris, D; Krivda, Marian; Librizzi, F; Manzari, Vito; Morel, M; Moretto, Sandra; Osmic, F; Pappalardo, G S; Pepato, Adriano; Pulvirenti, A; Riedler, P; Riggi, F; Santoro, R; Stefanini, G; Torcato De Matos, C; Turrisi, R; Tydesjo, H; Viesti, G; PH-EP

    2007-01-01

    The ALICE silicon pixel detector (SPD) comprises the two innermost layers of the ALICE inner tracker system. The SPD includes 120 detector modules (half-staves) each consisting of 10 ALICE pixel chips bump bonded to two silicon sensors and one multi-chip read-out module. Each pixel chip contains 8192 active cells, so that the total number of pixel cells in the SPD is ≈ 107. The on-detector read-out is based on a multi-chip-module containing 4 ASICs and an optical transceiver module. The constraints on material budget and detector module dimensions are very demanding.

  13. Internal electric-field-lines distribution in CdZnTe detectors measured using X-ray mapping

    International Nuclear Information System (INIS)

    Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Hossain, A.; Yang, G.; Yao, H.W.; James, R.B.

    2009-01-01

    The ideal operation of CdZnTe devices entails having a uniformly distributed internal electric field. Such uniformity especially is critical for thick long-drift-length detectors, such as large-volume CPG and 3-D multi-pixel devices. Using a high-spatial resolution X-ray mapping technique, we investigated the distribution of the electric field in real devices. Our measurements demonstrate that in thin detectors, 1 cm, with a large aspect ratio (thickness-to-width ratio), we observed two effects: the electric field lines bending away from or towards the side surfaces, which we called, respectively, the focusing field-line distribution and the defocusing field-line distribution. In addition to these large-scale variations, the field-line distributions were locally perturbed by the presence of extended defects and residual strains existing inside the crystals. We present our data clearly demonstrating the non-uniformity of the internal electric field

  14. The development of drift-strip detectors based on CdZnTe

    DEFF Research Database (Denmark)

    Gostilo, V.; Budtz-Jørgensen, Carl; Kuvvetli, Irfan

    2002-01-01

    The design and technological development of a CdZnTe drift strip detector is described. The device is based on a monocrystal of dimensions 10 x 10 x 3 mm(3) and has a pitch of 200 mum and a strip width of 100 mum. The strip length is 9.5 mm. The distribution of the leakage currents of the strips...

  15. Diagnostic X-ray spectrometry using a commercial CdZnTe detector

    International Nuclear Information System (INIS)

    Becker, P.H.B.

    1998-01-01

    X ray spectrometry using Ge or Si detectors is an established tool to measure characterization parameters of X-ray beams. This work describes how a commercial CdZnTe was used to perform diagnostic X-ray spectrometry. Spectra were measured for two X-ray machines and compared with similar data found in the literature with an agreement of 2% rms

  16. Operational experience with the ATLAS Pixel Detector

    CERN Document Server

    Ince, T; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost element of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.2% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  17. CVD diamond pixel detectors for LHC experiments

    CERN Document Server

    Wedenig, R; Bauer, C; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Pretzl, Klaus P; Procario, M; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Runólfsson, O; Russ, J; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R J; Trawick, M L; Trischuk, W; Vittone, E; Wagner, A; Walsh, A M; Weilhammer, Peter; White, C; Zeuner, W; Ziock, H J; Zöller, M

    1999-01-01

    This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described. (9 refs).

  18. CVD diamond pixel detectors for LHC experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wedenig, R.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Procario, M.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Runolfsson, O.; Russ, J.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Vittone, E.; Wagner, A.; Walsh, A.M.; Weilhammer, P.; White, C.; Zeuner, W.; Ziock, H.; Zoeller, M.; Blanquart, L.; Breugnion, P.; Charles, E.; Ciocio, A.; Clemens, J.C.; Dao, K.; Einsweiler, K.; Fasching, D.; Fischer, P.; Joshi, A.; Keil, M.; Klasen, V.; Kleinfelder, S.; Laugier, D.; Meuser, S.; Milgrome, O.; Mouthuy, T.; Richardson, J.; Sinervo, P.; Treis, J.; Wermes, N

    1999-08-01

    This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described.

  19. CVD diamond pixel detectors for LHC experiments

    International Nuclear Information System (INIS)

    Wedenig, R.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Procario, M.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Runolfsson, O.; Russ, J.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Vittone, E.; Wagner, A.; Walsh, A.M.; Weilhammer, P.; White, C.; Zeuner, W.; Ziock, H.; Zoeller, M.; Blanquart, L.; Breugnion, P.; Charles, E.; Ciocio, A.; Clemens, J.C.; Dao, K.; Einsweiler, K.; Fasching, D.; Fischer, P.; Joshi, A.; Keil, M.; Klasen, V.; Kleinfelder, S.; Laugier, D.; Meuser, S.; Milgrome, O.; Mouthuy, T.; Richardson, J.; Sinervo, P.; Treis, J.; Wermes, N.

    1999-01-01

    This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described

  20. CdZnTe detectors for gamma-ray Burst ArcSecond Imaging and Spectroscopy (BASIS)

    International Nuclear Information System (INIS)

    Stahle, C.M.; Palmer, D.; Bartlett, L.M.; Parsons, A.; Shi Zhiqing; Lisse, C.M.; Sappington, C.; Cao, N.; Shu, P.; Gehrels, N.; Teegarden, B.; Birsa, F.; Singh, S.; Odom, J.; Hanchak, C.; Tueller, J.; Barthelmy, S.; Krizmanic, J.; Barbier, L.

    1996-01-01

    A CdZnTe detector array is being developed for the proposed gamma-ray Burst ArcSecond Imaging and Spectroscopy (BASIS) spaceflight mission to accurately locate gamma-ray bursts, determine their distance scale, and measure the physical characteristics of the emission region. Two-dimensional strip detectors with 100 μm pitch have been fabricated and wire bonded to readout electronics to demonstrate the ability to localize 60 and 122 keV gamma-rays to less than 100 μm. Radiation damage studies on a CdZnTe detector exposed to MeV neutrons showed a small amount of activation but no detector performance degradation for fluences up to 10 10 neutrons/cm 2 . A 1 x 1 in. CdZnTe detector has also been flown on a balloon payload at 115 000 ft in order to measure the CdZnTe background rates. (orig.)

  1. Operational Experience with the ATLAS Pixel Detector

    CERN Document Server

    Lantzsch, Kerstin; The ATLAS collaboration

    2016-01-01

    Run 2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). In addition the Pixel detector was refurbished with new service quarter panels to recover about 3% of defective modules lost during run 1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning, operation and performance of the 4-layer Pixel Detector will be presented.

  2. Energy dispersive CdTe and CdZnTe detectors for spectral clinical CT and NDT applications

    Energy Technology Data Exchange (ETDEWEB)

    Barber, W.C., E-mail: william.barber@dxray.com [DxRay, Inc., Northridge, CA (United States); Interon AS, Asker (Norway); Wessel, J.C. [DxRay, Inc., Northridge, CA (United States); Interon AS, Asker (Norway); Nygard, E. [Interon AS, Asker (Norway); Iwanczyk, J.S. [DxRay, Inc., Northridge, CA (United States)

    2015-06-01

    We are developing room temperature compound semiconductor detectors for applications in energy-resolved high-flux single x-ray photon-counting spectral computed tomography (CT), including functional imaging with nanoparticle contrast agents for medical applications and non-destructive testing (NDT) for security applications. Energy-resolved photon-counting can provide reduced patient dose through optimal energy weighting for a particular imaging task in CT, functional contrast enhancement through spectroscopic imaging of metal nanoparticles in CT, and compositional analysis through multiple basis function material decomposition in CT and NDT. These applications produce high input count rates from an x-ray generator delivered to the detector. Therefore, in order to achieve energy-resolved single photon counting in these applications, a high output count rate (OCR) for an energy-dispersive detector must be achieved at the required spatial resolution and across the required dynamic range for the application. The required performance in terms of the OCR, spatial resolution, and dynamic range must be obtained with sufficient field of view (FOV) for the application thus requiring the tiling of pixel arrays and scanning techniques. Room temperature cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) compound semiconductors, operating as direct conversion x-ray sensors, can provide the required speed when connected to application specific integrated circuits (ASICs) operating at fast peaking times with multiple fixed thresholds per pixel provided the sensors are designed for rapid signal formation across the x-ray energy ranges of the application at the required energy and spatial resolutions, and at a sufficiently high detective quantum efficiency (DQE). We have developed high-flux energy-resolved photon-counting x-ray imaging array sensors using pixellated CdTe and CdZnTe semiconductors optimized for clinical CT and security NDT. We have also fabricated high

  3. Prototype of the stacked CdZnTe semiconductor detector for 16N measurement

    International Nuclear Information System (INIS)

    Nishizawa, Hiroshi; Inujima, Hiroshi; Fujiwara, Hirotsugu; Nakamura, Hiroaki

    2001-01-01

    Prototype of the Stacked CdZnTe Semiconductor Detector for Measurement The prototype model of the stacked CdZnTe semiconductor detector, which is able to measure the 6.13 MeV γ-ray from 16 N, was fabricated. The prototype's response calculation was carried out by Monte-Carlo method. The result of the response calculation agreed with the experiment data of check sources of 137 Cs and 60 Co, and 16 N which was measured at vicinity of the primary cooling water pipe of the nuclear reactor. The source spectra were unfolded with detector's response function obtained by simulation, and it is indicated that the incident γ-ray energy and its intensity ratio was identified and that the energy of 6 MeV γ-ray could be measured by the prototype of the stacked detector. (author)

  4. Charge sharing and charge loss in a cadmium-zinc-telluride fine-pixel detector array

    International Nuclear Information System (INIS)

    Gaskin, J.A.; Sharma, D.P.; Ramsey, B.D.

    2003-01-01

    Because of its high atomic number, room temperature operation, low noise, and high spatial resolution a cadmium-zinc-telluride multi-pixel detector is ideal for hard X-ray astrophysical observation. As part of on-going research at MSFC to develop multi-pixel CdZnTe detectors for this purpose, we have measured charge sharing and charge loss for a 4x4 (750 μm pitch), 1 mm thick pixel array and modeled these results using a Monte-Carlo simulation. This model was then used to predict the amount of charge sharing for a much finer pixel array (with a 300 μm pitch). Future work will enable us to compare the simulated results for the finer array to measured values

  5. Coplanar-grid CdZnTe detector with three-dimensional position sensitivity

    International Nuclear Information System (INIS)

    Luke, P.N.; Amman, M.; Lee, J.S.; Yaver, H.

    1998-06-01

    A 3-dimensional position-sensitive coplanar-grid detector design for use with compound semiconductors is described. This detector design maintains the advantage of a coplanar-grid detector in which good energy resolution can be obtained from materials with poor charge transport. Position readout in two dimensions is accomplished using proximity-sensing electrodes adjacent to the electron-collecting grid electrode of the detector. Additionally, depth information is obtained by taking the ratio of the amplitudes of the collecting grid signal and the cathode signal. Experimental results from a prototype CdZnTe detector are presented

  6. Operational Experience with the ATLAS Pixel Detector

    CERN Document Server

    Djama, Fares; The ATLAS collaboration

    2017-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction imposed by the higher collision energy, pileup and luminosity that are being delivered. The ATLAS tracking performance relies critically on the Pixel Detector, therefore, in view of Run-2 of LHC, the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and an additional optical link per module was added to overcome in some layers the readout bandwidth limitation when LHC will exceed the nominal peak luminosity by almost a factor of 3. The key features and challenges met during the IBL project will be presented, as well as its operational experience and Pixel Detector performance in LHC.

  7. Surface Passivation of CdZnTe Detector by Hydrogen Peroxide Solution Etching

    Science.gov (United States)

    Hayes, M.; Chen, H.; Chattopadhyay, K.; Burger, A.; James, R. B.

    1998-01-01

    The spectral resolution of room temperature nuclear radiation detectors such as CdZnTe is usually limited by the presence of conducting surface species that increase the surface leakage current. Studies have shown that the leakage current can be reduced by proper surface preparation. In this study, we try to optimize the performance of CdZnTe detector by etching the detector with hydrogen peroxide solution as function of concentration and etching time. The passivation effect that hydrogen peroxide introduces have been investigated by current-voltage (I-V) measurement on both parallel strips and metal-semiconductor-metal configurations. The improvements on the spectral response of Fe-55 and 241Am due to hydrogen peroxide treatment are presented and discussed.

  8. Applying Statistical Mechanics to pixel detectors

    International Nuclear Information System (INIS)

    Pindo, Massimiliano

    2002-01-01

    Pixel detectors, being made of a large number of active cells of the same kind, can be considered as significant sets to which Statistical Mechanics variables and methods can be applied. By properly redefining well known statistical parameters in order to let them match the ones that actually characterize pixel detectors, an analysis of the way they work can be performed in a totally new perspective. A deeper understanding of pixel detectors is attained, helping in the evaluation and comparison of their intrinsic characteristics and performance

  9. An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Guerra, P; Santos, A [Centro de Investigacion Biomedica de Bioningenieria, Biomateriales y Nanomedicina, CEEI-Modulo 3, C/ Maria de Luna, 11, 50018 Zaragoza (United States); Darambara, D G, E-mail: pguerra@ciber-bbn.e [Joint Department of Physics, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Fulham Road, London SW3 6JJ (United Kingdom)

    2009-09-07

    The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm{sup 3} CdZnTe pixellated detector.

  10. An investigation of performance characteristics of a pixellated room-temperature semiconductor detector for medical imaging

    International Nuclear Information System (INIS)

    Guerra, P; Santos, A; Darambara, D G

    2009-01-01

    The operation of any semiconductor detector depends on the movement of the charge carriers, which are created within the material when radiation passes through, as a result of energy deposition. The carrier movement in the bulk semiconductor induces charges on the metal electrodes, and therefore a current on the electrodes and the external circuit. The induced charge strongly depends on the material transport parameters as well as the geometrical dimensions of a pixellated semiconductor detector. This work focuses on the performance optimization in terms of energy resolution, detection efficiency and intrinsic spatial resolution of a room-temperature semiconductor pixellated detector based on CdTe/CdZnTe. It analyses and inter-relates these performance figures for various dimensions of CdTe and CdZnTe detectors and for an energy range spanning from x-ray (25 keV) to PET (511 keV) imaging. Monte Carlo simulations, which integrate a detailed and accurate noise model, are carried out to investigate several CdTe/CdZnTe configurations and to determine possible design specifications. Under the considered conditions, the simulations demonstrate the superiority of the CdZnTe over the CdTe in terms of energy resolution and sensitivity in the photopeak. Further, according to the results, the spatial resolution is maximized at high energies and the energy resolution at low energies, while a reasonable detection efficiency is achieved at high energies, with a 1 x 1 x 6 mm 3 CdZnTe pixellated detector.

  11. Algorithms for spectral calibration of energy-resolving small-pixel detectors

    International Nuclear Information System (INIS)

    Scuffham, J; Veale, M C; Wilson, M D; Seller, P

    2013-01-01

    Small pixel Cd(Zn)Te detectors often suffer from inter-pixel variations in gain, resulting in shifts in the individual energy spectra. These gain variations are mainly caused by inclusions and defects within the crystal structure, which affect the charge transport within the material causing a decrease in the signal pulse height. In imaging applications, spectra are commonly integrated over a particular peak of interest. This means that the individual pixels must be accurately calibrated to ensure that the same portion of the spectrum is integrated in every pixel. The development of large-area detectors with fine pixel pitch necessitates automated algorithms for this spectral calibration, due to the very large number of pixels. Algorithms for automatic spectral calibration require accurate determination of characteristic x-ray or photopeak positions on a pixelwise basis. In this study, we compare two peak searching spectral calibration algorithms for a small-pixel CdTe detector in gamma spectroscopic imaging. The first algorithm uses rigid search ranges to identify peaks in each pixel spectrum, based on the average peak positions across all pixels. The second algorithm scales the search ranges on the basis of the position of the highest-energy peak relative to the average across all pixels. In test spectra acquired with Tc-99m, we found that the rigid search algorithm failed to correctly identify the target calibraton peaks in up to 4% of pixels. In contrast, the scaled search algorithm failed in only 0.16% of pixels. Failures in the scaled search algorithm were attributed to the presence of noise events above the main photopeak, and possible non-linearities in the spectral response in a small number of pixels. We conclude that a peak searching algorithm based on scaling known peak spacings is simple to implement and performs well for the spectral calibration of pixellated radiation detectors

  12. Primary study of Monte Carlo simulation on CdZnTe nuclear detector

    International Nuclear Information System (INIS)

    Ren Shaojun; Sang Wenbin; Jin Wei; Li Wanwan; Zhang Qi; Min Jiahua

    2004-01-01

    The Monte Carlo simulation software is developed based on the operating principle of CdZnTe detector, the randomicity of γ ray reaction in the detector and the statistic rule of the amount of electron-hole pairs produced. First, the reaction depth of photons is calculated based on the disintegration rule. Secondly, the reaction section of every reaction is estimated and the reaction probability of the three atoms in CZT and the probability of every reaction of every atom are calculated. Based on these probabilities, the category of atoms and the type of reactions of a photon reacting with the detector are determined and the amount of electron-hole pairs produced by the photon is obtained. From the reaction depth and the amount of electron-hole pairs produced, the amount of charge collected can be calculated. The response energy spectra of γ ray in the CdZnTe detector are simulated by using the Monte Carlo software developed. The simulation results are well comparable with the data of the real CdZnTe devices. In addition, the ideal thickness of the device, which is of maximum detecting efficiency, is also obtained based on the analysis over the relationship between the thickness and the efficiency, assuming the device to be under the radiation of 57 Co source

  13. Technological aspects of gaseous pixel detectors fabrication

    NARCIS (Netherlands)

    Blanco Carballo, V.M.; Salm, Cora; Smits, Sander M.; Schmitz, Jurriaan; Melai, J.; Chefdeville, M.A.; van der Graaf, H.

    2007-01-01

    Integrated gaseous pixel detectors consisting of a metal punctured foil suspended in the order of 50μm over a pixel readout chip by means by SU-8 insulating pillars have been fabricated. SU-8 is used as sacrificial layer but metallization over uncrosslinked SU-8 presents adhesion and stress

  14. Preliminary test of an imaging probe for nuclear medicine using hybrid pixel detectors

    International Nuclear Information System (INIS)

    Bertolucci, E.; Maiorino, M.; Mettivier, G.; Montesi, M.C.; Russo, P.

    2002-01-01

    We are investigating the feasibility of an intraoperative imaging probe for lymphoscintigraphy with Tc-99m tracer, for sentinel node radioguided surgery, using the Medipix series of hybrid detectors coupled to a collimator. These detectors are pixelated semiconductor detectors bump-bonded to the Medipix1 photon counting read-out chip (64x64 pixel, 170 μm pitch) or to the Medipix2 chip (256x256 pixel, 55 μm pitch), developed by the European Medipix collaboration. The pixel detector we plan to use in the final version of the probe is a semi-insulating GaAs detector or a 1-2 mm thick CdZnTe detector. For the preliminary tests presented here, we used 300-μm thick silicon detectors, hybridized via bump-bonding to the Medipix1 chip. We used a tungsten parallel-hole collimator (7 mm thick, matrix array of 64x64 100 μm circular holes with 170 μm pitch), and a 22, 60 and 122 keV point-like (1 mm diameter) radioactive sources, placed at various distances from the detector. These tests were conducted in order to investigate the general feasibility of this imaging probe and its resolving power. Measurements show the high resolution but low efficiency performance of the detector-collimator set, which is able to image the 122 keV source with <1 mm FWHM resolution

  15. Parallel encoders for pixel detectors

    International Nuclear Information System (INIS)

    Nikityuk, N.M.

    1991-01-01

    A new method of fast encoding and determining the multiplicity and coordinates of fired pixels is described. A specific example construction of parallel encodes and MCC for n=49 and t=2 is given. 16 refs.; 6 figs.; 2 tabs

  16. Correction of diagnostic x-ray spectra measured with CdTe and CdZnTe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, M [Osaka Univ., Suita (Japan). Medical School; Kanamori, H; Toragaito, T; Taniguchi, A

    1996-07-01

    We modified the formula of stripping procedure presented by E. Di. Castor et al. We added the Compton scattering and separated K{sub {alpha}} radiation of Cd and Te (23 and 27keV, respectively). Using the new stripping procedure diagnostic x-ray spectra (object 4mm-Al) of tube voltage 50kV to 100kV for CdTe and CdZnTe detectors are corrected with comparison of those spectra for the Ge detector. The corrected spectra for CdTe and CdZnTe detectors coincide with those for Ge detector at lower tube voltage than 70kV. But the corrected spectra at higher tube voltage than 70kV do not coincide with those for Ge detector. The reason is incomplete correction for full energy peak efficiencies of real CdTe and CdZnTe detectors. (J.P.N.)

  17. Overview of the CMS Pixel Detector

    CERN Document Server

    Cerati, Giuseppe B

    2008-01-01

    The Compact Muon Solenoid Experiment (CMS) will start taking data at the Large Hadron Collider (LHC) in 2009. It will investigate the proton-proton collisions at $14~TeV$. A robust tracking combined with a precise vertex reconstruction is crucial to address the physics challenge of proton collisions at this energy. To this extent an all-silicon tracking system with very fine granularity has been built and now is in the final commissioning phase. It represents the largest silicon tracking detector ever built. The system is composed by an outer part, made of micro-strip detectors, and an inner one, made of pixel detectors. The pixel detector consists of three pixel barrel layers and two forward disks at each side of the interaction region. Each pixel sensor, both for the barrel and forward detectors, has $100 \\times 150$ $\\mu m^2$ cells for a total of 66 million pixels covering a total area of about $1~m^2$. The pixel detector will play a crucial role in the pattern recognition and the track reconstruction both...

  18. LISe pixel detector for neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, Elan; Hamm, Daniel [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN (United States); Wiggins, Brenden [Technology Development, Y-12 National Security Complex, Oak Ridge, TN (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, TN (United States); Milburn, Rob [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN (United States); Burger, Arnold [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN (United States); Department of Life and Physical Sciences, Fisk University, Nashville, TN (United States); Bilheux, Hassina [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Santodonato, Louis [Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Chvala, Ondrej [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN (United States); Stowe, Ashley [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN (United States); Technology Development, Y-12 National Security Complex, Oak Ridge, TN (United States); Department of Physics and Astronomy, Vanderbilt University, Nashville, TN (United States); Lukosi, Eric, E-mail: elukosi@utk.edu [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN (United States)

    2016-10-11

    Semiconducting lithium indium diselenide, {sup 6}LiInSe{sub 2} or LISe, has promising characteristics for neutron detection applications. The 95% isotopic enrichment of {sup 6}Li results in a highly efficient thermal neutron-sensitive material. In this study, we report on a proof-of-principle investigation of a semiconducting LISe pixel detector to demonstrate its potential as an efficient neutron imager. The LISe pixel detector had a 4×4 of pixels with a 550 µm pitch on a 5×5×0.56 mm{sup 3} LISe substrate. An experimentally verified spatial resolution of 300 µm was observed utilizing a super-sampling technique.

  19. Polarimetric analysis of a CdZnTe spectro-imager under multi-pixel irradiation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, M. [LIP-Laboratório de Instrumentação e Física Experimental de Partículas (Portugal); Physics Department, University of Coimbra, Coimbra (Portugal); Curado da Silva, R.M., E-mail: rui.silva@coimbra.lip.pt [LIP-Laboratório de Instrumentação e Física Experimental de Partículas (Portugal); Physics Department, University of Coimbra, Coimbra (Portugal); Maia, J.M. [LIP-Laboratório de Instrumentação e Física Experimental de Partículas (Portugal); Physics Department, University of Beira-Interior, Covilhã (Portugal); Simões, N. [LIP-Laboratório de Instrumentação e Física Experimental de Partículas (Portugal); Physics Department, University of Coimbra, Coimbra (Portugal); Marques, J. [LIP-Laboratório de Instrumentação e Física Experimental de Partículas (Portugal); Centro de Astrofísica, Universidade do Porto, Porto (Portugal); Pereira, L.; Trindade, A.M.F. [LIP-Laboratório de Instrumentação e Física Experimental de Partículas (Portugal); and others

    2016-12-21

    So far, polarimetry in high-energy astrophysics has been insufficiently explored due to the complexity of the required detection, electronic and signal processing systems. However, its importance is today largely recognized by the astrophysical community, therefore the next generation of high-energy space instruments will certainly provide polarimetric observations, contemporaneously with spectroscopy and imaging. We have been participating in high-energy observatory proposals submitted to ESA Cosmic Vision calls, such as GRI (Gamma-Ray Imager), DUAL and ASTROGAM, where the main instrument was a spectro-imager with polarimetric capabilities. More recently, the H2020 AHEAD project was launched with the objective to promote more coherent and mature future high-energy space mission proposals. In this context of high-energy proposal development, we have tested a CdZnTe detection plane prototype polarimeter under a partially polarized gamma-ray beam generated from an aluminum target irradiated by a {sup 22}Na (511 keV) radioactive source. The polarized beam cross section was 1 cm{sup 2}, allowing the irradiation of a wide multi-pixelated area where all the pixels operate simultaneously as a scatterer and as an absorber. The methods implemented to analyze such multi-pixel irradiation are similar to those required to analyze a spectro-imager polarimeter operating in space, since celestial source photons should irradiate its full pixilated area. Correction methods to mitigate systematic errors inherent to CdZnTe and to the experimental conditions were also implemented. The polarization level (~40%) and the polarization angle (precision of ±5° up to ±9°) obtained under multi-pixel irradiation conditions are presented and compared with simulated data.

  20. Operational Experience with the CMS Pixel Detector

    CERN Document Server

    INSPIRE-00205212

    2015-05-15

    In the first LHC running period the CMS-pixel detector had to face various operational challenges and had to adapt to the rapidly changing beam conditions. In order to maximize the physics potential and the quality of the data, online and offline calibrations were performed on a regular basis. The detector performed excellently with an average hit efficiency above 99\\% for all layers and disks. In this contribution the operational challenges of the silicon pixel detector in the first LHC run and the current long shutdown are summarized and the expectations for 2015 are discussed.

  1. A silicon pixel detector prototype for the CLIC vertex detector

    CERN Multimedia

    AUTHOR|(INSPIRE)INSPIRE-00714258

    2017-01-01

    A silicon pixel detector prototype for CLIC, currently under study for the innermost detector surrounding the collision point. The detector is made of a High-Voltage CMOS sensor (top) and a CLICpix2 readout chip (bottom) that are glued to each other. Both parts have a size of 3.3 x 4.0 $mm^2$ and consist of an array of 128 x 128 pixels of 25 x 25 $\\micro m^2$ size.

  2. The pin pixel detector--neutron imaging

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Rhodes, N J; Schooneveld, E M; Simmons, J E; Stephenson, R

    2002-01-01

    The development and testing of a neutron gas pixel detector intended for application in neutron diffraction studies is reported. Using standard electrical connector pins as point anodes, the detector is based on a commercial 100 pin connector block. A prototype detector of aperture 25.4 mmx25.4 mm has been fabricated, giving a pixel size of 2.54 mm which matches well to the spatial resolution typically required in a neutron diffractometer. A 2-Dimensional resistive divide readout system has been adapted to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics. The timing properties of the device match well to the requirements of the ISIS-pulsed neutron source.

  3. Fluctuations in induced charge introduced by Te inclusions within CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Bale, Derek S.

    2010-01-01

    Recently, homogenization theory based on a multiple-scale perturbation of the electron transport equation has been used to derive a mathematical framework for modeling the excess charge lost to Te inclusions within radiation detectors based on semi-insulating cadmium zinc telluride (CdZnTe). In that theory, the heterogeneous material is mathematically replaced by a homogenized CdZnTe crystal whose effective electron attenuation length incorporates the additional uniform electron trapping caused by the inclusions. In this paper, the homogenization theory is extended to incorporate fluctuations in the induced charge (i.e., charge collection nonuniformities) introduced by the random position and size distributions of a noncorrelated population of small (i.e, <20 μm) Te inclusions. Analysis of the effective parameters derived within the homogenized framework is used to develop a probability distribution of effective electron attenuation lengths, and therefore effective mobility-lifetime products, as a function of both the position and size distribution of Te inclusions. Example distributions are detailed for the case of an exponential size distribution at various number densities. Further, it is demonstrated that the inclusion-induced material nonuniformities derived in this paper can be numerically sampled efficiently, making them applicable to Monte Carlo device simulation of realistic CdZnTe detectors. Simulated charge induction maps and pulse-height spectra are presented and compared to recently published measurements.

  4. Material-specific imaging system using energy-dispersive X-ray diffraction and spatially resolved CdZnTe detectors with potential application in breast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Barbes, Damien, E-mail: damien.barbes@cea.fr [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Tabary, Joachim, E-mail: joachim.tabary@cea.fr [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Paulus, Caroline, E-mail: caroline.paulus@cea.fr [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Hazemann, Jean-Louis, E-mail: jean-louis.hazemann@neel.cnrs.fr [Univ.Grenoble Alpes, Inst NEEL, F-38042 Grenoble (France); CNRS, Inst NEEL, F-38042 Grenoble (France); Verger, Loïck, E-mail: loick.verger@cea.fr [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France)

    2017-03-11

    This paper presents a coherent X-ray-scattering imaging technique using a multipixel energy-dispersive system. Without any translation, the technique produces specific 1D image from data recorded by a single CdZnTe detector pixel using subpixelation techniques. The method is described in detail, illustrated by a simulation and then experimentally validated. As the main considered application of our study is breast imaging, this validation involves 2D imaging of a phantom made of plastics mimicking breast tissues. The results obtained show that our system can specifically image the phantom using a single detector pixel. For the moment, in vivo breast imaging applications remain difficult, as the dose delivered by the system is too high, but some adjustments are considered for further work.

  5. Development of CdZnTe X-ray detectors at DSRI

    DEFF Research Database (Denmark)

    van Pamelen, M.A.J.; Budtz-Jørgensen, Carl; Kuvvetli, Irfan

    2000-01-01

    An overview of the development of CdZnTe X-ray detectors at the Danish Space Research Institute is presented. Initiated in the beginning of 1996, the main motivation at that time was to develop focal plane detectors for the novel type of hard X-ray telescopes, which are currently under study...... developed a technique, which, with the use of microstrip electrodes, is able to compensate for the signal loss caused by trapping of positive charge carriers. This technique leads to a dramatic improvement of the achievable energy resolution, even for crystals of poor quality. With the technique, hole...

  6. Upgrade of ATLAS ITk Pixel Detector

    CERN Document Server

    Huegging, Fabian; The ATLAS collaboration

    2017-01-01

    The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenges to the ATLAS tracker. The current inner detector will be replaced with an entirely-silicon inner tracker (ITk) which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation levels are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors and low mass global and local support structures. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the ITk ATLAS Pixel detector developments as well as different layout options will be reviewed.

  7. Simulation study of pixel detector charge digitization

    Science.gov (United States)

    Wang, Fuyue; Nachman, Benjamin; Sciveres, Maurice; Lawrence Berkeley National Laboratory Team

    2017-01-01

    Reconstruction of tracks from nearly overlapping particles, called Tracking in Dense Environments (TIDE), is an increasingly important component of many physics analyses at the Large Hadron Collider as signatures involving highly boosted jets are investigated. TIDE makes use of the charge distribution inside a pixel cluster to resolve tracks that share one of more of their pixel detector hits. In practice, the pixel charge is discretized using the Time-over-Threshold (ToT) technique. More charge information is better for discrimination, but more challenging for designing and operating the detector. A model of the silicon pixels has been developed in order to study the impact of the precision of the digitized charge distribution on distinguishing multi-particle clusters. The output of the GEANT4-based simulation is used to train neutral networks that predict the multiplicity and location of particles depositing energy inside one cluster of pixels. By studying the multi-particle cluster identification efficiency and position resolution, we quantify the trade-off between the number of ToT bits and low-level tracking inputs. As both ATLAS and CMS are designing upgraded detectors, this work provides guidance for the pixel module designs to meet TIDE needs. Work funded by the China Scholarship Council and the Office of High Energy Physics of the U.S. Department of Energy under contract DE-AC02-05CH11231.

  8. Multielement CdZnTe detectors for high-efficiency, ambient-temperature gamma-ray spectroscopy

    International Nuclear Information System (INIS)

    Prettyman, T.H.; Moss, C.E.; Sweet, M.R.; Ianakiev, K.; Reedy, R.C.; Li, J.; Valentine, J.D.

    1998-01-01

    CdZnTe is an attractive alternative to scintillator-based technology for ambient-temperature, gamma-ray spectroscopy. Large, single-element devices up to 3500 mm 3 have been developed for gamma-ray spectroscopy and are now available commercially. Because CdZnTe is a wide band-gap semiconductor, it can operate over a wide range of ambient temperatures with minimal power consumption. Over this range, CdZnTe detectors routinely yield better overall performance for gamma-ray spectroscopy than scintillator detectors. Manufacturing issues and material electronic properties limit the maximum size of single-element CdZnTe detectors. The authors are investigating methods to combine CdZnTe detectors together to improve detection efficiency and overall performance of gamma-ray spectroscopy. The applications include the assay and identification of radioisotopes for nuclear material safeguards and nonproliferation (over the energy range 50 keV to 1 MeV), and the analysis of elemental composition for planetary science (over the energy range 1 MeV to 10 MeV). Design issues for the two energy ranges are summarized

  9. Study on the mechanism of using IR illumination to improve the carrier transport performance of CdZnTe detector

    Science.gov (United States)

    Mao, Yifei; Zhang, Jijun; Lin, Liwen; Lai, Jianming; Min, Jiahua; Liang, Xiaoyan; Huang, Jian; Tang, Ke; Wang, Linjun

    2018-04-01

    Different wavelength IR light (770-1150 nm) was used to evaluate the effect of IR light on the carrier transport performance of CdZnTe detector. The effective mobility-lifetime product (μτ*) of CdZnTe achieved 10-2 cm2 V-1 when the IR wavelength was in the range of 820-920 nm, but decreased to 1 × 10-4 cm2 V-1 when the wavelength was longer than 920 nm. The mechanism about how IR light affecting the carrier transport property of CdZnTe detector was analyzed with Shockley-Read-Hall model. The defect of doubly ionized Cd vacancy ([VCd]2-) was found to be the main factor that assist IR light affecting the μτ of CdZnTe detector. The photoconductive experiment under 770-1150 nm IR illumination was carried out, and three kinds of photocurrent curve were detected and analyzed by solving the Hecht equation. The experiments demonstrated the effect of [VCd]2- defect on the carrier transport property of CdZnTe detector under IR illumination.

  10. Commissioning of the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Golling, Tobias

    2008-01-01

    The ATLAS pixel detector is a high precision silicon tracking device located closest to the LHC interaction point. It belongs to the first generation of its kind in a hadron collider experiment. It will provide crucial pattern recognition information and will largely determine the ability of ATLAS to precisely track particle trajectories and find secondary vertices. It was the last detector to be installed in ATLAS in June 2007, has been fully connected and tested in-situ during spring and summer 2008, and is ready for the imminent LHC turn-on. The highlights of the past and future commissioning activities of the ATLAS pixel system are presented

  11. CDZNTE ROOM-TEMPERATURE SEMICONDUCTOR GAMMA-RAY DETECTOR FOR NATIONAL-SECURITY APPLICATIONS.

    Energy Technology Data Exchange (ETDEWEB)

    CAMARDA,G.S.; BOLOTNIKOV, A.E.; CUI, Y.; HOSSAIN, A.; KOHMAN, K.T.; JAMES, R.B.

    2007-05-04

    One important mission of the Department of Energy's National Nuclear Security Administration is to develop reliable gamma-ray detectors to meet the widespread needs of users for effective techniques to detect and identify special nuclear- and radioactive-materials. Accordingly, the Nonproliferation and National Security Department at Brookhaven National Laboratory was tasked to evaluate existing technology and to develop improved room-temperature detectors based on semiconductors, such as CdZnTe (CZT). Our research covers two important areas: Improving the quality of CZT material, and exploring new CZT-based gamma-ray detectors. In this paper, we report on our recent findings from the material characterization and tests of actual CZT devices fabricated in our laboratory and from materials/detectors supplied by different commercial vendors. In particular, we emphasize the critical role of secondary phases in the current CZT material and issues in fabricating the CZT detectors, both of which affect their performance.

  12. A CdZnTe slot-scanned detector for digital mammography

    International Nuclear Information System (INIS)

    Mainprize, James G.; Ford, Nancy L.; Yin Shi; Gordon, Eli E.; Hamilton, William J.; Tuemer, Tuemay O.; Yaffe, Martin J.

    2002-01-01

    A new high-resolution detector has been developed for use in a slot-scanned digital mammography system. The detector is a hybrid device that consists of a CCD operating in time-delay integration mode that is bonded to a 150-μm-thick CdZnTe photoconductor array. The CCD was designed with a detector element pitch of 50 μm. Two devices were evaluated with differing crystalline quality. Incomplete charge collection was a source of reduction in DQE. This occurs in both devices due to characteristically low mobility-lifetime products for CdZnTe, with the greatest losses demonstrated by the multicrystalline sample. The mobility-lifetime products for the multicrystalline device were found to be 2.4x10 -4 and 4.0x10 -7 cm 2 /V for electrons and holes, respectively. The device constructed with higher quality single crystal CdZnTe demonstrated mobility-lifetime products of 1.0x10 -4 and 4.4x10 -6 cm 2 /V for electrons and holes. The MTF and DQE for the device were measured at several exposures and results were compared to predictions from a linear systems model of signal and noise propagation. The MTF at a spatial frequency of 10 mm -1 exceeded 0.18 and 0.56 along the scan and slot directions, respectively. Scanning motion and CCD design limited the resolution along the scan direction. For an x-ray beam from a tungsten target tube with 40 μm molybdenum filtration operated at 26 kV, the single crystal device demonstrated a DQE(0) of 0.70±0.02 at 7.1x10 -6 C/kg (27 mR) exposure to the detector, despite its relatively poor charge collection efficiency

  13. Performance simulation of an x-ray detector for spectral CT with combined Si and Cd[Zn]Te detection layers.

    Science.gov (United States)

    Herrmann, Christoph; Engel, Klaus-Jürgen; Wiegert, Jens

    2010-12-21

    The most obvious problem in obtaining spectral information with energy-resolving photon counting detectors in clinical computed tomography (CT) is the huge x-ray flux present in conventional CT systems. At high tube voltages (e.g. 140 kVp), despite the beam shaper, this flux can be close to 10⁹ Mcps mm⁻² in the direct beam or in regions behind the object, which are close to the direct beam. Without accepting the drawbacks of truncated reconstruction, i.e. estimating missing direct-beam projection data, a photon-counting energy-resolving detector has to be able to deal with such high count rates. Sub-structuring pixels into sub-pixels is not enough to reduce the count rate per pixel to values that today's direct converting Cd[Zn]Te material can cope with (≤ 10 Mcps in an optimistic view). Below 300 µm pixel pitch, x-ray cross-talk (Compton scatter and K-escape) and the effect of charge diffusion between pixels are problematic. By organising the detector in several different layers, the count rate can be further reduced. However this alone does not limit the count rates to the required level, since the high stopping power of the material becomes a disadvantage in the layered approach: a simple absorption calculation for 300 µm pixel pitch shows that the required layer thickness of below 10 Mcps/pixel for the top layers in the direct beam is significantly below 100 µm. In a horizontal multi-layer detector, such thin layers are very difficult to manufacture due to the brittleness of Cd[Zn]Te. In a vertical configuration (also called edge-on illumination (Ludqvist et al 2001 IEEE Trans. Nucl. Sci. 48 1530-6, Roessl et al 2008 IEEE NSS-MIC-RTSD 2008, Conf. Rec. Talk NM2-3)), bonding of the readout electronics (with pixel pitches below 100 µm) is not straightforward although it has already been done successfully (Pellegrini et al 2004 IEEE NSS MIC 2004 pp 2104-9). Obviously, for the top detector layers, materials with lower stopping power would be advantageous

  14. Operation of CdZnTe Semiconductor Detectors in Liquid Scintillator for the COBRA Experiment

    International Nuclear Information System (INIS)

    Oldorf, Christian

    2015-08-01

    COBRA, the Cadmium-Zinc-Telluride O-neutrino double-Beta Research Apparatus, is an experiment aiming for the measurement of the neutrinoless double beta decay with several isotopes, in particular 116 Cd, 106 Cd and 130 Te. A highly granular large scale experiment with about 400 kg of CdZnTe semiconductor detectors is currently under development. To provide evidence for the neutrinoless double beta decay of 116 Cd, a background rate in the order of 10 -3 counts/keV/kg/a is needed to achieve the required half-life sensitivity of at least 2 . 10 26 years. To reach this target, the detectors have to be operated in a highly pure environment, shielded from external radiation. Liquid scintillator is a promising candidate as a circum fluent replacement for the currently used lacquer. Next to the function as highly pure passivation material, liquid scintillator also acts as a neutron shield and active veto for external gammas. Within this thesis, the design, construction and assembly of a test set-up is described. The operation of four CdZnTe detectors after several years of storage in liquid scintillator is demonstrated. Next to extensive material compatibility tests prior to the assembly, the commissioning of the set-up and the characterization of the detectors are shown. Finally, results concerning the background reduction capability of liquid scintillator and the detection of cosmic muons are presented and compared to a Monte Carlo simulation.

  15. Charge sharing in silicon pixel detectors

    CERN Document Server

    Mathieson, K; Seller, P; Prydderch, M L; O'Shea, V; Bates, R L; Smith, K M; Rahman, M

    2002-01-01

    We used a pixellated hybrid silicon X-ray detector to study the effect of the sharing of generated charge between neighbouring pixels over a range of incident X-ray energies, 13-36 keV. The system is a room temperature, energy resolving detector with a Gaussian FWHM of 265 eV at 5.9 keV. Each pixel is 300 mu m square, 300 mu m deep and is bump bonded to matching read out electronics. The modelling packages MEDICI and MCNP were used to model the complete X-ray interaction and the subsequent charge transport. Using this software a model is developed which reproduces well the experimental results. The simulations are then altered to explore smaller pixel sizes and different X-ray energies. Charge sharing was observed experimentally to be 2% at 13 keV rising to 4.5% at 36 keV, for an energy threshold of 4 keV. The models predict that up to 50% of charge may be lost to the neighbouring pixels, for an X-ray energy of 36 keV, when the pixel size is reduced to 55 mu m.

  16. Developments of the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Andreazza, Attilio

    2004-01-01

    The ATLAS silicon pixel detector is the innermost tracking device of the ATLAS experiment at the Large Hardon Collider, consisting of more than 1700 modules for a total sensitive area of about 1.7m2 and over 80 million pixel cells. The concept is a hybrid of front-end chips bump bonded to the pixel sensor. The elementary pixel cell has 50μmx400μm size, providing pulse height information via the time over threshold technique. Prototype devices with oxygenated silicon sensor and rad-hard electronics built in the IBM 0.25μm process have been tested and maintain good resolution, efficiency and timing performances even after receiving the design radiation damage of 1015neq/cm2

  17. Comparison of CdZnTe neutron detector models using MCNP6 and Geant4

    Science.gov (United States)

    Wilson, Emma; Anderson, Mike; Prendergasty, David; Cheneler, David

    2018-01-01

    The production of accurate detector models is of high importance in the development and use of detectors. Initially, MCNP and Geant were developed to specialise in neutral particle models and accelerator models, respectively; there is now a greater overlap of the capabilities of both, and it is therefore useful to produce comparative models to evaluate detector characteristics. In a collaboration between Lancaster University, UK, and Innovative Physics Ltd., UK, models have been developed in both MCNP6 and Geant4 of Cadmium Zinc Telluride (CdZnTe) detectors developed by Innovative Physics Ltd. Herein, a comparison is made of the relative strengths of MCNP6 and Geant4 for modelling neutron flux and secondary γ-ray emission. Given the increasing overlap of the modelling capabilities of MCNP6 and Geant4, it is worthwhile to comment on differences in results for simulations which have similarities in terms of geometries and source configurations.

  18. Barrier controlled carrier trapping of extended defects in CdZnTe detector

    International Nuclear Information System (INIS)

    Guo, Rongrong; Jie, Wanqi; Xu, Yadong; Yu, Hui; Zha, Gangqiang; Wang, Tao; Ren, Jie

    2015-01-01

    Transient current techniques using alpha particle source were utilized to study the influence of extended defects on the electron drift time and the detector performance of CdZnTe crystals. Different from the case of trapping through isolated point defect, a barrier controlled trapping model was used to explain the mechanism of carrier trapping at the extended defects. The effect of extended defects on the photoconductance was studied by laser beam induced transient current (LBIC) measurement. The results demonstrate that the Schottky-type depletion space charge region is induced at the vicinity of the extended defects, which further distorts the internal electric field distribution and affects the carrier trajectory in CdZnTe crystals. The relationship between the electron drift time and detector performance has been established. - Highlights: • The barrier controlled trapping model was developed around extended defects. • Electron mobility and E-field distribution were distorted by space charge depletion region. • Extended defects act as a recombination-activated region. • The relationships between extended defects and detector performance were established

  19. PROTON RADIOGRAPHY WITH THE PIXEL DETECTOR TIMEPIX

    Directory of Open Access Journals (Sweden)

    Václav Olšanský

    2016-12-01

    Full Text Available This article presents the processing of radiographic data acquired using the position-sensitive hybrid semiconductor pixel detector Timepix. Measurements were made on thin samples at the medical ion-synchrotron HIT [1] in Heidelberg (Germany with a 221 MeV proton beam. The charge is energy by the particles crossing the sample is registered for generation of image contrast. Experimental data from the detector were processed for derivation of the energy loss of each proton using calibration matrices. The interaction point of the protons on the detector were determined with subpixel resolution by model fitting of the individual signals in the pixelated matrix. Three methods were used for calculation of these coordinates: Hough transformation, 2D Gaussian fitting and estimate the 2D mean. Parameters of calculation accuracy and calculation time are compared for each method. The final image was created by method with best parameters.

  20. Sensor development for the CMS pixel detector

    CERN Document Server

    Bölla, G; Horisberger, R P; Kaufmann, R; Rohe, T; Roy, A

    2002-01-01

    The CMS experiment which is currently under construction at the Large Hadron Collider (LHC) at CERN (Geneva, Switzerland) will contain a pixel detector which provides in its final configuration three space points per track close to the interaction point of the colliding beams. Because of the harsh radiation environment of the LHC, the technical realization of the pixel detector is extremely challenging. The readout chip as the most damageable part of the system is believed to survive a particle fluence of 6x10 sup 1 sup 4 n sub e sub q /cm sup 2 (All fluences are normalized to 1 MeV neutrons and therefore all components of the hybrid pixel detector have to perform well up to at least this fluence. As this requires a partially depleted operation of the silicon sensors after irradiation-induced type inversion of the substrate, an ''n in n'' concept has been chosen. In order to perform IV-tests on wafer level and to hold accidentally unconnected pixels close to ground potential, a resistive path between the pixe...

  1. Wafer-scale pixelated detector system

    Science.gov (United States)

    Fahim, Farah; Deptuch, Grzegorz; Zimmerman, Tom

    2017-10-17

    A large area, gapless, detection system comprises at least one sensor; an interposer operably connected to the at least one sensor; and at least one application specific integrated circuit operably connected to the sensor via the interposer wherein the detection system provides high dynamic range while maintaining small pixel area and low power dissipation. Thereby the invention provides methods and systems for a wafer-scale gapless and seamless detector systems with small pixels, which have both high dynamic range and low power dissipation.

  2. Technology development for SOI monolithic pixel detectors

    International Nuclear Information System (INIS)

    Marczewski, J.; Domanski, K.; Grabiec, P.; Grodner, M.; Jaroszewicz, B.; Kociubinski, A.; Kucharski, K.; Tomaszewski, D.; Caccia, M.; Kucewicz, W.; Niemiec, H.

    2006-01-01

    A monolithic detector of ionizing radiation has been manufactured using silicon on insulator (SOI) wafers with a high-resistivity substrate. In our paper the integration of a standard 3 μm CMOS technology, originally designed for bulk devices, with fabrication of pixels in the bottom wafer of a SOI substrate is described. Both technological sequences have been merged minimizing thermal budget and providing suitable properties of all the technological layers. The achieved performance proves that fully depleted monolithic active pixel matrix might be a viable option for a wide spectrum of future applications

  3. Infrared LED Enhanced Spectroscopic CdZnTe Detector Working under High Fluxes of X-rays

    Directory of Open Access Journals (Sweden)

    Jakub Pekárek

    2016-09-01

    Full Text Available This paper describes an application of infrared light-induced de-polarization applied on a polarized CdZnTe detector working under high radiation fluxes. We newly demonstrate the influence of a high flux of X-rays and simultaneous 1200-nm LED illumination on the spectroscopic properties of a CdZnTe detector. CdZnTe detectors operating under high radiation fluxes usually suffer from the polarization effect, which occurs due to a screening of the internal electric field by a positive space charge caused by photogenerated holes trapped at a deep level. Polarization results in the degradation of detector charge collection efficiency. We studied the spectroscopic behavior of CdZnTe under various X-ray fluxes ranging between 5 × 10 5 and 8 × 10 6 photons per mm 2 per second. It was observed that polarization occurs at an X-ray flux higher than 3 × 10 6 mm − 2 ·s − 1 . Using simultaneous illumination of the detector by a de-polarizing LED at 1200 nm, it was possible to recover X-ray spectra originally deformed by the polarization effect.

  4. The ATLAS Pixel Detector operation and performance

    CERN Document Server

    Andreazza, A; The ATLAS collaboration

    2010-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. It consists of 1744 silicon sensors equipped with approximately $80 imes 10^6$~electronic channels, providing typically three measurement points with high resolution for particles emerging from the beam-interaction region. The complete Pixel Detector has been taking part in cosmic-ray data-taking since 2008. Since November 2009 it has been operated with LHC colliding beams at $sqrt{s}=900$~GeV, 2.36~TeV and 7 TeV. The detector operated with an active fraction of 97.2% at a threshold of 3500~$e$, showing a noise occupancy rate better than $10^{-9}$~hit/pixel/BC and a track association efficiency of 99%. The Lorentz angle for electrons in silicon is measured to be $ heta_mathrm{L}=12.11^circ pm 0.09^circ$ and its temperature dependence has been verified. The pulse height information from the time-over-threshold technique allows to improve the point resolution using charge sharing and to perform parti...

  5. Characterization of the CMS Pixel Detectors

    CERN Document Server

    Gu, Weihua

    2002-01-01

    In 2005 the Large Hadron Collider (LHC) will start the pp collisions at a high luminosity and at a center of mass energy of 14 TeV. The primary goal of the experimental programme is the search of the Higgs boson(s) and the supersymmetric particles. The programme is also proposed to detect a range of diverse signatures in order to provide guidance for future physics. The pixel detector system makes up the innermost part of the CMS experiment, which is one of the two general purpose detectors at the LHC. The main tasks of the system are vertex detection and flavor tagging. The high luminosity and the high particle multiplicity as well as the small bunch spacing at the LHC impose great challenges on the pixel detectors: radiation hardness of sensors and electronics, fast signal processing and a high granularity are the essential requirements. This thesis concentrates on the study of the suitability of two test stands, which are implemented to characterize the CMS pixel detectors: one is con-cerned with test puls...

  6. Rapid pulse annealing of CdZnTe detectors for reducing electronic noise

    Science.gov (United States)

    Voss, Lars; Conway, Adam; Nelson, Art; Nikolic, Rebecca J.; Payne, Stephen A.; Swanberg, Jr., Erik Lars

    2018-05-01

    A combination of doping, rapid pulsed optical and/or thermal annealing, and unique detector structure reduces or eliminates sources of electronic noise in a CdZnTe (CZT) detector. According to several embodiments, methods of forming a detector exhibiting minimal electronic noise include: pulse-annealing at least one surface of a detector comprising CZT for one or more pulses, each pulse having a duration of .about.0.1 seconds or less. The at least one surface may optionally be ion-implanted. In another embodiment, a CZT detector includes a detector surface with two or more electrodes operating at different electric potentials and coupled to the detector surface; and one or more ion-implanted CZT surfaces on or in the detector surface, each of the one or more ion-implanted CZT surfaces being independently connected to one of the two or more electrodes and the surface of the detector. At least two of the ion-implanted surfaces are in electrical contact.

  7. The Belle II DEPFET pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Hans-Günther, E-mail: moser@mpp.mpg.de

    2016-09-21

    The Belle II experiment at KEK (Tsukuba, Japan) will explore heavy flavour physics (B, charm and tau) at the starting of 2018 with unprecedented precision. Charged particles are tracked by a two-layer DEPFET pixel device (PXD), a four-layer silicon strip detector (SVD) and the central drift chamber (CDC). The PXD will consist of two layers at radii of 14 mm and 22 mm with 8 and 12 ladders, respectively. The pixel sizes will vary, between 50 μm×(55–60) μm in the first layer and between 50 μm×(70–85) μm in the second layer, to optimize the charge sharing efficiency. These innermost layers have to cope with high background occupancy, high radiation and must have minimal material to reduce multiple scattering. These challenges are met using the DEPFET technology. Each pixel is a FET integrated on a fully depleted silicon bulk. The signal charge collected in the ‘internal gate’ modulates the FET current resulting in a first stage amplification and therefore very low noise. This allows very thin sensors (75 μm) reducing the overall material budget of the detector (0.21% X{sub 0}). Four fold multiplexing of the column parallel readout allows read out a full frame of the pixel matrix in only 20 μs while keeping the power consumption low enough for air cooling. Only the active electronics outside the detector acceptance has to be cooled actively with a two phase CO{sub 2} system. Furthermore the DEPFET technology offers the unique feature of an electronic shutter which allows the detector to operate efficiently in the continuous injection mode of superKEKB.

  8. Evaluation of CdZnTe as neutron detector around medical accelerators

    International Nuclear Information System (INIS)

    Martin-Martin, A.; Iniguez, M. P.; Luke, P. N.; Barquero, R.; Lorente, A.; Morchon, J.; Gallego, E.; Quincoces, G.; Marti-Climent, J. M.

    2009-01-01

    The operation of electron linear accelerators (LINACs) and cyclotrons can produce a mixed gamma-neutron field composed of energetic neutrons coming directly from the source and scattered lower energy neutrons. The thermal neutron detection properties of a non-moderated coplanar-grid CdZnTe (CZT) gamma-ray detector close to an 18 MV electron LINAC and an 18 MeV proton cyclotron producing the radioisotope 18 F for positron emission tomography are investigated. The two accelerators are operated at conditions producing similar thermal neutron fluence rates of the order of 104 cm -2 s -1 at the measurement locations. The counting efficiency of the CZT detector using the prompt 558 keV photopeak following 113 Cd thermal neutron capture is evaluated and a good neutron detection performance is found at the two installations. (authors)

  9. Performance optimization of CdTe and CdZnTe detectors for γ-spectrometry

    International Nuclear Information System (INIS)

    Montemont, Guillaume

    2000-01-01

    This study deals with room-temperature gamma spectrometry with CdTe and CdZnTe semiconductor detectors. The aim was the improvement of energy resolution and detection efficiency. Some different phenomena have been investigated. Electronic noise knowledge has enabled us to optimize the design of filtering. Charge transport induces signal shape uncertainty and the processing circuit has been adapted in order to account for these variations. Study and simulation of electrical current induction process has permitted the development of a new Frisch-grid based detection structure. We have reached 3% energy resolutions at 122 keV without detection efficiency loss. Finally, the remaining limits of detector performances have been estimated by focusing on gamma interaction phenomena and material non-uniformity problems. (author) [fr

  10. Simulation of the anode structure for capacitive frisch grid CdZnTe detectors

    International Nuclear Information System (INIS)

    Min Jiahua; Shi Zhubin; Sang Wenbin; Zhao Hengyu; Teng Jianyong; Qian Yongbiao; Liu Jishan

    2009-01-01

    CdZnTe (CZT) capacitive Frisch grid detectors can achieve a higher detecting resolution. The anode structrure might have an important role in improving the weighting potential distribution of the detectors. In this paper, four anode structures of capacitive Frisch grid structures have been analyzed with FE simulation, based on a 3-dimensional weighting potential analysis. The weighting potential distributions in modified anode devices (Model B, C and D) are optimized compared with a square device (Model A). In model C and D, the abrupt weighting potential can be well modified. However, with increased radius of the circular electrode in Model C the weighting potential platform away from the anode becomes higher and higher and in Model D, the weighting potential does not vary too much. (authors)

  11. Characterization of large volume CdZnTe detectors with a quad-grid structure for the COBRA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rohatsch, Katja [TU Dresden, Institut fuer Kern- und Teilchenphysik, 01069 Dresden (Germany); Collaboration: COBRA-Collaboration

    2016-07-01

    The COBRA experiment uses room temperature semiconductor detectors made of Cadmium-Zinc-Telluride, which contains several double beta isotopes, to search for neutrinoless double beta-decay. To compensate for poor hole transport in CdZnTe the detectors are equipped with a coplanar grid (CPG) instead of a planar anode. Currently, a demonstrator setup consisting of 64 1 cm{sup 3} CPG-detectors is in operation at the LNGS in Italy to prove the concept and to determine the long-term stability of the detectors and the instrumentation. For a future large scale experiment it is planned to use larger CdZnTe detectors with a volume of 6 cm{sup 3}, because of the better surface-to-volume ratio and the higher full energy detection efficiency. This will also reduce the background contribution of surface contaminations. Before the installation at the LNGS the new detector design is validated and studied in detail. This talk presents a laboratory experiment for the characterization with γ-radiation of 6 cm{sup 3} CdZnTe quad-grid detectors. The anode of such a detector is divided into four sub-CPGs. The characterization routine consists of the determination of the optimal working point and two-dimensional spatially resolved scans with a highly collimated γ-source.

  12. Influence of infrared stimulation on spectroscopy characteristics of co-planar grid CdZnTe detectors

    International Nuclear Information System (INIS)

    Fjodorov, V.; Ivanov, V.; Loutchanski, A.

    2015-01-01

    It was previously found that illumination with monochromatic infrared (IR) light with wavelengths close to the absorption edge of the CdZnTe exert significant positive influence on the spectrometric characteristics of quasi-hemispherical CdZnTe detectors at room temperature. In this paper, preliminary results of IR stimulation on the spectrometric characteristics of coplanar-grid CdZnTe detectors as well as results of further studies of planar and quasi-hemispherical detectors are presented. Coplanar-grid detectors of 10 mm x 10 mm x 10 mm from Redlen Technologies and commercial available IR LEDs with different wavelengths of 800-1000 nm were used in the experiments. Influence of intensity and direction of IR illumination on the detector's characteristics was studied. Analysis of signals shapes from the preamplifiers outputs at registration of alpha particles showed that IR illumination leads to a change in the shapes of these signals. This may indicate changes in electric fields distributions. An improvement in energy resolution at gamma-energy of 662 keV was observed with quasi-hemispherical and co-planar detectors at the certain levels of IR illumination intensity. The most noticeable effect of IR stimulation was observed with quasi-hemispherical detectors. It is due with optimization of charge collection conditions in the quasi-hemispherical detectors under IT stimulation. (authors)

  13. Influence of hydrostatic pressure on nuclear radiation detector's properties based on semiconductor alloy CdZnTe

    International Nuclear Information System (INIS)

    Kutnij, V.E.; Kutnij, D.V.; Rybka, A.V.; Nakonechnyj, D.V.; Babun, A.V.

    2003-01-01

    The influence of hydrostatic pressure on properties of CdZnTe semiconductor detectors (Cd-50,Zn-2,Te-48 mas.%, 5 centre dot 5 centre dot 2 mm) was investigated. Were considered different types of hydrostatic treatment at 100 MPa, second hydrostatic treatment at 100 MPa and 200 MPa. Hydrostatic pressure influence on detectors electric resistance, J-V characteristics and spectrometric parameters was determined

  14. Alignment of the upgraded CMS pixel detector

    CERN Document Server

    Schroder, Matthias

    2018-01-01

    The all-silicon tracking system of the CMS experiment provides excellent resolution for charged tracks and an efficient tagging of heavy-flavour jets. After a new pixel detector has been installed during the LHC technical stop at the beginning of 2017, the positions, orientations, and surface curvatures of the sensors needed to be determined with a precision at the order of a few micrometres to ensure the required physics performance. This is far beyond the mechanical mounting precision but can be achieved using a track-based alignment procedure that minimises the track-hit residuals of reconstructed tracks. The results are carefully validated with data-driven methods. In this article, results of the CMS tracker alignment in 2017 from the early detector-commissioning phase and the later operation are presented, that were derived using several million reconstructed tracks in pp-collision and cosmic-ray data. Special emphasis is put on the alignment of the new pixel detector.

  15. Semiconductor pixel detectors for digital mammography

    International Nuclear Information System (INIS)

    Novelli, M.; Amendolia, S.R.; Bisogni, M.G.; Boscardin, M.; Dalla Betta, G.F.; Delogu, P.; Fantacci, M.E.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Venturelli, L.; Zucca, S.

    2003-01-01

    We present some results obtained with silicon and gallium arsenide pixel detectors to be applied in the field of digital mammography. Even though GaAs is suitable for medical imaging applications thanks to its atomic number, which allows a very good detection efficiency, it often contains an high concentrations of traps which decrease the charge collection efficiency (CCE). So we have analysed both electrical and spectroscopic performance of different SI GaAs diodes as a function of concentrations of dopants in the substrate, in order to find a material by which we can obtain a CCE allowing the detection of all the photons that interact in the detector. Nevertheless to be able to detect low contrast details, efficiency and CCE are not the only parameters to be optimized; also the stability of the detection system is fundamental. In the past we have worked with Si pixel detectors; even if its atomic number does not allow a good detection efficiency at standard thickness, it has a very high stability. So keeping in mind the need to increase the Silicon detection efficiency we performed simulations to study the behaviour of the electrical potential in order to find a geometry to avoid the risk of electrical breakdown

  16. Semiconductor pixel detectors for digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Novelli, M. E-mail: marzia.novelli@pi.infn.it; Amendolia, S.R.; Bisogni, M.G.; Boscardin, M.; Dalla Betta, G.F.; Delogu, P.; Fantacci, M.E.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Venturelli, L.; Zucca, S

    2003-08-21

    We present some results obtained with silicon and gallium arsenide pixel detectors to be applied in the field of digital mammography. Even though GaAs is suitable for medical imaging applications thanks to its atomic number, which allows a very good detection efficiency, it often contains an high concentrations of traps which decrease the charge collection efficiency (CCE). So we have analysed both electrical and spectroscopic performance of different SI GaAs diodes as a function of concentrations of dopants in the substrate, in order to find a material by which we can obtain a CCE allowing the detection of all the photons that interact in the detector. Nevertheless to be able to detect low contrast details, efficiency and CCE are not the only parameters to be optimized; also the stability of the detection system is fundamental. In the past we have worked with Si pixel detectors; even if its atomic number does not allow a good detection efficiency at standard thickness, it has a very high stability. So keeping in mind the need to increase the Silicon detection efficiency we performed simulations to study the behaviour of the electrical potential in order to find a geometry to avoid the risk of electrical breakdown.

  17. Survey of the ATLAS Pixel Detector Components

    International Nuclear Information System (INIS)

    Andreazza, A.; Kostyukhim, V.; Madaras, R.

    2008-01-01

    This document provides a description of the survey performed on different components of the ATLAS Pixel Detector at different stages of its assembly. During the production of the ATLAS pixel detector great care was put in the geometrical survey of the location of the sensitive area of modules. This had a double purpose: (1) to provide a check of the quality of the assembly procedure and assure tolerances in the geometrical assembly were met; and (2) to provide an initial point for the alignment (the so called 'as-built detector'), better than the ideal geometry. Since direct access to the sensitive area becomes more and more difficult with the progress of the assembly, the survey needed to be performed at different stages: after module loading on the local supports (sectors and staves) and after assembly of the local supports in disks or halfshells. Different techniques were used, including both optical 2D and 3D surveys and mechanical survey. This document summarizes the survey procedures, the analysis done on the collected data and how survey data are stored in case they will need to be accessed in the future

  18. IDeF-X ECLAIRs: A CMOS ASIC for the Readout of CdTe and CdZnTe Detectors for High Resolution Spectroscopy

    International Nuclear Information System (INIS)

    Gevin, O.; Baron, P.; Coppolani, X.; Delagnes, E.; Lugiez, F.; Daly, F.; Limousin, O.; Meuris, A.; Pinsard, F.; Renaud, D.

    2009-01-01

    The very last member of the IDeF-X ASIC family is presented: IDeF-X ECLAIRs is a 32-channel front end ASIC designed for the readout of Cadmium Telluride (CdTe) and Cadmium Zinc Telluride (CdZnTe) Detectors. Thanks to its noise performance (Equivalent Noise Charge floor of 33 e - rms) and to its radiation hardened design (Single Event Latch-up Linear Energy Transfer threshold of 56 MeV.cm 2 .mg -1 ), the chip is well suited for soft X-rays energy discrimination and high energy resolution, 'space proof', hard X-ray spectroscopy. We measured an energy low threshold of less than 4 keV with a 10 pF input capacitor and a minimal reachable sensitivity of the Equivalent Noise Charge (ENC) to input capacitance of less than 7e - /pF obtained with a 6 μs peak time. IDeF-X ECLAIRs will be used for the readout of 6400 CdTe Schottky mono-pixel detectors of the 2D coded mask imaging telescope ECLAIRs aboard the SVOM satellite. IDeF-X ECLAIRs (or IDeF-X V2) has also been designed for the readout of a pixelated CdTe detector in the miniature spectro-imager prototype Caliste 256 that is currently foreseen for the high energy detector module of the Simbol-X mission. (authors)

  19. TE INCLUSIONS AND THEIR RELATIONSHIP TO THE PERFORMANCE OF CDZNTE DETECTORS.

    Energy Technology Data Exchange (ETDEWEB)

    CARINI, G.A.; BOLOTNIKOV, A.E.; CAMARDA, G.S.; CUI, Y.; JACKSON, H.; BURGER, A.; KOHMAN, K.T.; LI, L.; JAMES, R.B.

    2006-08-13

    Te-rich secondary phases existing in CdZnTe (CZT) single crystals degrade the spectroscopic performance of these detectors. An unpredictable number of charges are trapped, corresponding to the abundance of these microscopic defects, thereby leading to fluctuations in the total collected charge and strongly affecting the uniformity of charge-collection efficiency. These effects, observed in thin planar detectors, also were found to be the dominant cause of the low performance of thick detectors, wherein the fluctuations accumulate along the charge's drift path. Reducing the size of Te inclusions from a virtual diameter of 10-20 {micro}m down to less than 5 {micro}m already allowed us to produce Frisch-ring detectors with a resolution as good as {approx}0.8% FWHM at 662 keV: Understanding and modeling the mechanisms involving Te-rich secondary phases and charge loss requires systematic studies on a spatial scale never before realized. Here, we describe a dedicated beam-line recently established at BNL's National Synchrotron Light Source for characterizing semiconductor detectors along with a IR system with counting capability that permits us to correlate the concentration of defects with the devices' performances.

  20. Control of electric field in CdZnTe radiation detectors by above-bandgap light

    International Nuclear Information System (INIS)

    Franc, J.; Dědič, V.; Rejhon, M.; Zázvorka, J.; Praus, P.; Touš, J.; Sellin, P. J.

    2015-01-01

    We have studied the possibility of above bandgap light induced depolarization of CdZnTe planar radiation detector operating under high flux of X-rays by Pockels effect measurements. In this contribution, we show a similar influence of X-rays at 80 kVp and LED with a wavelength of 910 nm irradiating the cathode on polarization of the detector due to an accumulation of a positive space charge of trapped photo-generated holes. We have observed the depolarization of the detector under simultaneous cathode-site illumination with excitation LED at 910 nm and depolarization above bandgap LED at 640 nm caused by trapping of drifting photo-generated electrons. Although the detector current is quite high during this depolarization, we have observed that it decreases relatively fast to its initial value after switching off the depolarizing light. In order to get detailed information about physical processes present during polarization and depolarization and, moreover, about associated deep levels, we have performed the Pockels effect infrared spectral scanning measurements of the detector without illumination and under illumination in polarized and optically depolarized states

  1. Control of electric field in CdZnTe radiation detectors by above-bandgap light

    Energy Technology Data Exchange (ETDEWEB)

    Franc, J.; Dědič, V.; Rejhon, M.; Zázvorka, J.; Praus, P. [Institute of Physics of Charles University, Prague (Czech Republic); Touš, J. [Crytur Ltd., Turnov (Czech Republic); Sellin, P. J. [Department of Physics, University of Surrey, Guildford (United Kingdom)

    2015-04-28

    We have studied the possibility of above bandgap light induced depolarization of CdZnTe planar radiation detector operating under high flux of X-rays by Pockels effect measurements. In this contribution, we show a similar influence of X-rays at 80 kVp and LED with a wavelength of 910 nm irradiating the cathode on polarization of the detector due to an accumulation of a positive space charge of trapped photo-generated holes. We have observed the depolarization of the detector under simultaneous cathode-site illumination with excitation LED at 910 nm and depolarization above bandgap LED at 640 nm caused by trapping of drifting photo-generated electrons. Although the detector current is quite high during this depolarization, we have observed that it decreases relatively fast to its initial value after switching off the depolarizing light. In order to get detailed information about physical processes present during polarization and depolarization and, moreover, about associated deep levels, we have performed the Pockels effect infrared spectral scanning measurements of the detector without illumination and under illumination in polarized and optically depolarized states.

  2. Application of CdZnTe Gamma-Ray Detector for Imaging Corrosion under Insulation

    Science.gov (United States)

    Abdullah, J.; Yahya, R.

    2007-05-01

    Corrosion under insulation (CUI) on the external wall of steel pipes is a common problem in many types of industrial plants. This is mainly due to the presence of moisture or water in the insulation materials. This type of corrosion can cause failures in areas that are not normally of a primary concern to an inspection program. The failures are often the result of localised corrosion and not general wasting over a large area. These failures can tee catastrophic in nature or at least have an adverse economic effect in terms of downtime and repairs. There are a number of techniques used today for CUI investigations. The main ones are profile radiography, pulse eddy current, ultrasonic spot readings and insulation removal. A new system now available is portable Pipe-CUI-Profiler. The nucleonic system is based on dual-beam gamma-ray absorption technique using Cadmium Zinc Telluride (CdZnTe) semiconductor detectors. The Pipe-CUI-Profiler is designed to inspect pipes of internal diameter 50, 65, 80, 90, 100, 125 and 150 mm. Pipeline of these sizes with aluminium or thin steel sheathing, containing fibreglass or calcium silicate insulation to thickness of 25, 40 and 50 mm can be inspected. The system has proven to be a safe, fast and effective method of inspecting pipe in industrial plant operations. This paper describes the application of gamma-ray techniques and CdZnTe semiconductor detectors in the development of Pipe-CUI-Profiler for non-destructive imaging of corrosion under insulation of steel pipes. Some results of actual pipe testing in large-scale industrial plant will be presented.

  3. Application of CdZnTe Gamma-Ray Detector for Imaging Corrosion under Insulation

    International Nuclear Information System (INIS)

    Abdullah, J.; Yahya, R.

    2007-01-01

    Corrosion under insulation (CUI) on the external wall of steel pipes is a common problem in many types of industrial plants. This is mainly due to the presence of moisture or water in the insulation materials. This type of corrosion can cause failures in areas that are not normally of a primary concern to an inspection program. The failures are often the result of localised corrosion and not general wasting over a large area. These failures can tee catastrophic in nature or at least have an adverse economic effect in terms of downtime and repairs. There are a number of techniques used today for CUI investigations. The main ones are profile radiography, pulse eddy current, ultrasonic spot readings and insulation removal. A new system now available is portable Pipe-CUI-Profiler. The nucleonic system is based on dual-beam gamma-ray absorption technique using Cadmium Zinc Telluride (CdZnTe) semiconductor detectors. The Pipe-CUI-Profiler is designed to inspect pipes of internal diameter 50, 65, 80, 90, 100, 125 and 150 mm. Pipeline of these sizes with aluminium or thin steel sheathing, containing fibreglass or calcium silicate insulation to thickness of 25, 40 and 50 mm can be inspected. The system has proven to be a safe, fast and effective method of inspecting pipe in industrial plant operations. This paper describes the application of gamma-ray techniques and CdZnTe semiconductor detectors in the development of Pipe-CUI-Profiler for non-destructive imaging of corrosion under insulation of steel pipes. Some results of actual pipe testing in large-scale industrial plant will be presented

  4. ATLAS rewards two pixel detector suppliers

    CERN Multimedia

    2007-01-01

    Peter Jenni, ATLAS spokesperson, presented the ATLAS supplier award to Herbert Reichl, IZM director, and to Simonetta Di Gioia, from the SELEX company.Two of ATLAS’ suppliers were awarded prizes at a ceremony on Wednesday 13 June attended by representatives of the experiment’s management and of CERN. The prizes went to the Fraunhofer Institut für Zuverlässigkeit und Mikrointegration (IZM) in Berlin and the company SELEX Sistemi Integrati in Rome for the manufacture of modules for the ATLAS pixel detector. SELEX supplied 1500 of the modules for the tracker, while IZM produced a further 1300. The modules, each made up of 46080 channels, form the active part of the ATLAS pixel detector. IZM and SELEX received the awards for the excellent quality of their work: the average number of faulty channels per module was less than 2.10-3. They also stayed within budget and on schedule. The difficulty they faced was designing modules based on electronic components and sensor...

  5. Clustering method to process signals from a CdZnTe detector

    International Nuclear Information System (INIS)

    Zhang, Lan; Takahashi, Hiroyuki; Fukuda, Daiji; Nakazawa, Masaharu

    2001-01-01

    The poor mobility of holes in a compound semiconductor detector results in the imperfect collection of the primary charge deposited in the detector. Furthermore the fluctuation of the charge loss efficiency due to the change in the hole collection path length seriously degrades the energy resolution of the detector. Since the charge collection efficiency varies with the signal waveform, we can expect the improvement of the energy resolution through a proper waveform signal processing method. We developed a new digital signal processing technique, a clustering method which derives typical patterns containing the information on the real situation inside a detector from measured signals. The obtained typical patterns for the detector are then used for the pattern matching method. Measured signals are classified through analyzing the practical waveform variation due to the charge trapping, the electric field and the crystal defect etc. Signals with similar shape are placed into the same cluster. For each cluster we calculate an average waveform as a reference pattern. Using these reference patterns obtained from all the clusters, we can classify other measured signal waveforms from the same detector. Then signals are independently processed according to the classified category and form corresponding spectra. Finally these spectra are merged into one spectrum by multiplying normalization coefficients. The effectiveness of this method was verified with a CdZnTe detector of 2 mm thick and a 137 Cs gamma-ray source. The obtained energy resolution as improved to about 8 keV (FWHM). Because the clustering method is only related to the measured waveforms, it can be applied to any type and size of detectors and compatible with any type of filtering methods. (author)

  6. CdTe and CdZnTe gamma ray detectors for medical and industrial imaging systems

    International Nuclear Information System (INIS)

    Eisen, Y.; Shor, A.; Mardor, I.

    1999-01-01

    CdTe and CdZnTe X-ray and gamma ray detectors in the form of single elements or as segmented monolithic detectors have been shown to be useful in medical and industrial imaging systems. These detectors possess inherently better energy resolution than scintillators coupled to either photodiodes or photomultipliers, and together with application specific integrated circuits they lead to compact imaging systems of enhanced spatial resolution and better contrast resolution. Photopeak efficiencies of these detectors is greatly affected by a relatively low hole mobility-lifetime product. Utilizing these detectors as highly efficient good spectrometers, demands use of techniques to improve their charge collection properties, i.e., correct for variations in charge losses at different depths of interaction in the detector. The corrections for the large hole trapping are made either by applying electronic techniques or by fabricating detector or electrical contacts configurations which differ from the commonly used planar detectors. The following review paper is divided into three parts: The first part discusses detector contact configurations for enhancing photopeak efficiencies and the single carrier collection approach which leads to improved energy resolutions and photopeak efficiencies at high gamma ray energies. The second part demonstrates excellent spectroscopic results using thick CdZnTe segmented monolithic pad and strip detectors showing energy resolutions less than 2% FWHM at 356 keV gamma rays. The third part discusses advantages and disadvantages of CdTe and CdZnTe detectors in imaging systems and describes new developments for medical diagnostics imaging systems

  7. Detector performance of the ALICE silicon pixel detector

    CERN Document Server

    Cavicchioli, C

    2011-01-01

    The ALICE Silicon Pixel Detector (SPD) forms the two innermost layers of the ALICE Inner Tracking System (ITS). It consists of two barrel layers of hybrid silicon pixel detectors at radii of 39 and 76 mm. The physics targets of the ALICE experiment require that the material budget of the SPD is kept within approximate to 1\\%X(0) per layer. This has set some stringent constraints on the design and construction of the SPD. A unique feature of the ALICE SPD is that it is capable of providing a prompt trigger signal, called Fast-OR, which contributes to the L0 trigger decision. The pixel trigger system allows to apply a set of algorithms for the trigger selection, and its output is sent to the Central Trigger Processor (CTP). The detector has been installed in the experiment in summer 2007. During the first injection tests in June 2008 the SPD was able to record the very first sign of life of the LHC by registering secondary particles from the beam dumped upstream the ALICE experiment. In the following months the...

  8. Development of flat panel X-ray detector utilizing a CdZnTe film as conversion layer

    International Nuclear Information System (INIS)

    Tokuda, Satoshi; Kishihara, Hiroyuki; Kaino, Masatomo; Sato, Toshiyuki

    2006-01-01

    A polycrystalline CdZnTe film formed by the CSS (closed-spaced sublimation) method is one of the most promising materials as a conversion layer of next-generation highly efficient flat-panel X-ray detectors. Therefore, we have developed a prototype of a new flat-panel X-ray detector (a sensing region of 3 inches by 3 inches) with the film and evaluated its commercial feasibility. This paper describes evaluation of the physical and imaging properties of the prototype and explains the features of the CdZnTe film and the construction, specifications, and fabrication procedures of the prototype. Also included in this paper are formation of a semiconductor thin film barrier layer by the CBD (chemical bath deposition) method and conjunction of a sensor substrate and a TFT array substrate with the bump electrodes formed by screen printing, both of which we have developed during the course of the development of the prototype. (author)

  9. Pixel Detectors for Particle Physics and Imaging Applications

    CERN Document Server

    Wermes, N

    2003-01-01

    Semiconductor pixel detectors offer features for the detection of radiation which are interesting for particle physics detectors as well as for imaging e.g. in biomedical applications (radiography, autoradiography, protein crystallography) or in Xray astronomy. At the present time hybrid pixel detectors are technologically mastered to a large extent and large scale particle detectors are being built. Although the physical requirements are often quite different, imaging applications are emerging and interesting prototype results are available. Monolithic detectors, however, offer interesting features for both fields in future applications. The state of development of hybrid and monolithic pixel detectors, excluding CCDs, and their different suitability for particle detection and imaging, is reviewed.

  10. Operational Experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Keil, M; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  11. Operational experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Hirschbuehl, D; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.7% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  12. Operational experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Lapoire, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  13. Operational Experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Lapoire, C; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as B-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures and detector performance. The detector performance is excellent: 96.2% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification.

  14. Operational Experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Keil, M

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including calibration procedures, timing optimization and detector performance. The detector performance is excellent: approximately 97% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  15. Operational experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Ince, T; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 96.8% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  16. Operational experience with the ATLAS Pixel detector at the LHC

    CERN Document Server

    Deluca, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this paper, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5\\% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, ...

  17. Operational Experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Lange, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump- bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, a...

  18. Operational experience with the ATLAS Pixel detector at the LHC

    CERN Document Server

    Deluca, C; The ATLAS collaboration

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: 97,5% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, an...

  19. Operational Experience with the ATLAS Pixel Detector at the LHC

    CERN Document Server

    Keil, M; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including calibration procedures, timing optimization and detector performance. The detector performance is excellent: ~96 % of the pixels are operational, noise occupancy and hit efficiency e...

  20. Sensor Development for the CMS Pixel Detector

    CERN Document Server

    Rohe, T; Chiochia, V; Cremaldi, L M; Cucciarelli, S; Dorkhov, A; Konecki, M; Prokofiev, K; Regenfus, C; Sanders, D A; Son, S; Speer, T; Swartz, M

    2003-01-01

    This paper reports on a current R&D activity for the sensor part of the CMS pixel detector. Devices featuring several design and technology options have been irradiated up to a proton fluence of 1E15 (1MeV Neutron)/cm**2 at the CERN PS. Afterwards they have been bump bonded to unirradiated readout chips. The chip allows a non zero suppressed full analogue readout and therefore a good characterization of the sensors in terms of noise and charge collection properties. The samples have been tested using high energy pions in the H2 beam line of the CERN SPS in June and September 2003. The results of this test beam are presented and the differences between the sensor options are discussed.

  1. Pulse shaping system research of CdZnTe radiation detector for high energy x-ray diagnostic

    Science.gov (United States)

    Li, Miao; Zhao, Mingkun; Ding, Keyu; Zhou, Shousen; Zhou, Benjie

    2018-02-01

    As one of the typical wide band-gap semiconductor materials, the CdZnTe material has high detection efficiency and excellent energy resolution for the hard X-ray and the Gamma ray. The generated signal of the CdZnTe detector needs to be transformed to the pseudo-Gaussian pulse with a small impulse-width to remove noise and improve the energy resolution by the following nuclear spectrometry data acquisition system. In this paper, the multi-stage pseudo-Gaussian shaping-filter has been investigated based on the nuclear electronic principle. The optimized circuit parameters were also obtained based on the analysis of the characteristics of the pseudo-Gaussian shaping-filter in our following simulations. Based on the simulation results, the falling-time of the output pulse was decreased and faster response time can be obtained with decreasing shaping-time τs-k. And the undershoot was also removed when the ratio of input resistors was set to 1 to 2.5. Moreover, a two stage sallen-key Gaussian shaping-filter was designed and fabricated by using a low-noise voltage feedback operation amplifier LMH6628. A detection experiment platform had been built by using the precise pulse generator CAKE831 as the imitated radiation pulse which was equivalent signal of the semiconductor CdZnTe detector. Experiment results show that the output pulse of the two stage pseudo-Gaussian shaping filter has minimum 200ns pulse width (FWHM), and the output pulse of each stage was well consistent with the simulation results. Based on the performance in our experiment, this multi-stage pseudo-Gaussian shaping-filter can reduce the event-lost caused by pile-up in the CdZnTe semiconductor detector and improve the energy resolution effectively.

  2. Cumulative effects of Te precipitates in CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Bolotnikov, A.E.; Camarda, G.S.; Carini, G.A.; Cui, Y.; Li, L.; James, R.B.

    2007-01-01

    High-quality radiation detector-grade CdZnTe material is free from large-scale defects, such as grain boundaries, twins, and large Te or Cd inclusions (>50 μm), although it usually contains high concentrations of uniformly distributed Te inclusions and precipitates, typically of ∼20-μm-diameter size or smaller. We address the effects of the small-size Te precipitates on charge collection in CZT detectors, the significance of which is not yet well characterized. The strong correlation that we earlier found between the high-resolution X-ray maps and IR images proved that even small Te precipitates can trap substantial fractions of charge from the electron cloud. In this work, we modeled the transport of an electron cloud across idealized CZT devices containing Te precipitates to demonstrate that their cumulative effect can explain the degradation of energy resolution and the detection efficiency losses observed in actual CZT devices. Due to lack of experimental data on how the Te precipitates interact with an electron cloud, we developed a simplified (phenomenological) model based on the geometrical aspects of the problem. Despite its simplicity, the model correctly reproduced many experimental facts and gave quantitative predictions on the extent to which the presence of Te precipitates and inclusions can be tolerated. The broadening of the electron cloud due to repulsion and diffusion is at the core of the problem, making even low concentrations of small precipitates important in the device's performance

  3. IDeF-X ECLAIRs: A CMOS ASIC for the Readout of CdTe and CdZnTe Detectors for High Resolution Spectroscopy

    Science.gov (United States)

    Gevin, Olivier; Baron, Pascal; Coppolani, Xavier; Daly, FranÇois; Delagnes, Eric; Limousin, Olivier; Lugiez, Francis; Meuris, Aline; Pinsard, FrÉdÉric; Renaud, Diana

    2009-08-01

    The very last member of the IDeF-X ASIC family is presented: IDeF-X ECLAIRs is a 32-channel front end ASIC designed for the readout of Cadmium Telluride (CdTe) and Cadmium Zinc Telluride (CdZnTe) Detectors. Thanks to its noise performance (Equivalent Noise Charge floor of 33 e- rms) and to its radiation hardened design (Single Event Latchup Linear Energy Transfer threshold of 56 MeV.cm2.mg-1), the chip is well suited for soft X-rays energy discrimination and high energy resolution, ldquospace proof,rdquo hard X-ray spectroscopy. We measured an energy low threshold of less than 4 keV with a 10 pF input capacitor and a minimal reachable sensitivity of the Equivalent Noise Charge (ENC) to input capacitance of less than 7 e-/pF obtained with a 6 mus peak time. IDeF-X ECLAIRs will be used for the readout of 6400 CdTe Schottky monopixel detectors of the 2D coded mask imaging telescope ECLAIRs aboard the SVOM satellite. IDeF-X ECLAIRs (or IDeF-X V2) has also been designed for the readout of a pixelated CdTe detector in the miniature spectro-imager prototype Caliste 256 that is currently foreseen for the high energy detector module of the Simbol-X mission.

  4. Simulation of single-event energy-deposition spreading in a hybrid pixellated detector for gamma imaging

    CERN Document Server

    Manach, E

    2002-01-01

    In the framework of the Medipix2 Collaboration, a new photon-counting chip is being developed made of a 256x256 array of 55 mu m-side square pixels. Although the chip was primarily developed for semiconductor X-ray imagers, we think that this type of device could be used in applications such as decommissioning of nuclear facilities where typical sources have gamma-ray energies in the range of a few hundred keV. In order to enhance the detection efficiency in this energy range, we envisage connecting the Medipix2 chip to a CdTe or CdZnTe substrate (at least 1 mm thick). The small pixel size, the thickness of the Cd(Zn)Te substrate and the high photon energy motivate us to estimate first the spatial energy spreading following a photon interaction inside the detector. Estimations were made using the MCNP Monte Carlo package by simulating the individual energy distribution for each primary photon interaction. As an illustration of our results, simulating a 660 keV gamma source, we found that there are two pixels ...

  5. Precision tracking with a single gaseous pixel detector

    NARCIS (Netherlands)

    Tsigaridas, S.; van Bakel, N.; Bilevych, Y.; Gromov, V.; Hartjes, F.; Hessey, N.P.; de Jong, P.; Kluit, R.

    2015-01-01

    The importance of micro-pattern gaseous detectors has grown over the past few years after successful usage in a large number of applications in physics experiments and medicine. We develop gaseous pixel detectors using micromegas-based amplification structures on top of CMOS pixel readout chips.

  6. The ALICE silicon pixel detector system

    International Nuclear Information System (INIS)

    Kapusta, S.

    2009-01-01

    The Large Hadron Collider (LHC) is again reaching its startup phase at the European Organization for Particle Physics (CERN). The LHC started its operation on the 10 th of September, 2008 with huge success managing to sent the the first beam successfully around the entire ring in less than an hour after the first injection in one direction, and later that day in the opposite direction. Unfortunately, on the 19 th of September, an accident occurred during the 5.5 TeV magnet commissioning in Sector 34, which will significantly delay the operation of the LHC. The ALICE experiment will exploit the collisions of accelerated ions produced at the LHC to study strongly interacting matter at extreme densities and high temperatures. e ALICE Silicon Pixel Detector (SPD) represents the two innermost layers of the ALICE Inner Traing System (ITS) located at radii of 3.9 cm and 7.6 cm from the Interaction Point (IP). One of the main tasks of the SPD is to provide precise traing information. is information is fundamental for the study of weak decays of heavy flavor particles, since the corresponding signature is a secondary vertex separated from the primary vertex only by a few hundred micrometers. e tra density could be as high as 80 tracks per cm 2 in the innermost SPD layer as a consequence of a heavy ion collision. The SPD will provide a spatial resolution of around ≅12 μm in the rφ direction and ≅70 μm in the z direction. The expected occupancy of the SPD ranges from 0.4% to 1.5% which makes it an excellent charged particle multiplicity detector in the pseudorapidity region |η| < 2. Furthermore, by combining all possible hits in the SPD, one can get a rough estimate of the position of the primary interaction. One of the challenges is the tight material budget constraint (<1% radiation length per layer) in order to limit the scattering of the traversing particles. e silicon sensor and its readout chip have a total thickness of only 350 μm and the signal lines from the

  7. Monte Carlo based performance assessment of different animal PET architectures using pixellated CZT detectors

    International Nuclear Information System (INIS)

    Visvikis, D.; Lefevre, T.; Lamare, F.; Kontaxakis, G.; Santos, A.; Darambara, D.

    2006-01-01

    The majority of present position emission tomography (PET) animal systems are based on the coupling of high-density scintillators and light detectors. A disadvantage of these detector configurations is the compromise between image resolution, sensitivity and energy resolution. In addition, current combined imaging devices are based on simply placing back-to-back and in axial alignment different apparatus without any significant level of software or hardware integration. The use of semiconductor CdZnTe (CZT) detectors is a promising alternative to scintillators for gamma-ray imaging systems. At the same time CZT detectors have the potential properties necessary for the construction of a truly integrated imaging device (PET/SPECT/CT). The aims of this study was to assess the performance of different small animal PET scanner architectures based on CZT pixellated detectors and compare their performance with that of state of the art existing PET animal scanners. Different scanner architectures were modelled using GATE (Geant4 Application for Tomographic Emission). Particular scanner design characteristics included an overall cylindrical scanner format of 8 and 24 cm in axial and transaxial field of view, respectively, and a temporal coincidence window of 8 ns. Different individual detector modules were investigated, considering pixel pitch down to 0.625 mm and detector thickness from 1 to 5 mm. Modified NEMA NU2-2001 protocols were used in order to simulate performance based on mouse, rat and monkey imaging conditions. These protocols allowed us to directly compare the performance of the proposed geometries with the latest generation of current small animal systems. Results attained demonstrate the potential for higher NECR with CZT based scanners in comparison to scintillator based animal systems

  8. Semiconductor Pixel detectors and their applications in life sciences

    International Nuclear Information System (INIS)

    Jakubek, J

    2009-01-01

    Recent advances in semiconductor technology allow construction of highly efficient and low noise pixel detectors of ionizing radiation. Steadily improving quality of front end electronics enables fast digital signal processing in each pixel which offers recording of more complete information about each detected quantum (energy, time, number of particles). All these features improve an extend applicability of pixel technology in different fields. Some applications of this technology especially for imaging in life sciences will be shown (energy and phase sensitive X-ray radiography and tomography, radiography with heavy charged particles, neutron radiography, etc). On the other hand a number of obstacles can limit the detector performance if not handled. The pixel detector is in fact an array of individual detectors (pixels), each of them has its own efficiency, energy calibration and also noise. The common effort is to make all these parameters uniform for all pixels. However an ideal uniformity can be never reached. Moreover, it is often seen that the signal in one pixel can affect the neighbouring pixels due to various reasons (e.g. charge sharing). All such effects have to be taken into account during data processing to avoid false data interpretation. A brief view into the future of pixel detectors and their applications including also spectroscopy, tracking and dosimetry is given too. Special attention is paid to the problem of detector segmentation in context of the charge sharing effect.

  9. Status of the digital pixel array detector for protein crystallography

    CERN Document Server

    Datte, P; Beuville, E; Endres, N; Druillole, F; Luo, L; Millaud, J E; Xuong, N H

    1999-01-01

    A two-dimensional photon counting digital pixel array detector is being designed for static and time resolved protein crystallography. The room temperature detector will significantly enhance monochromatic and polychromatic protein crystallographic through-put data rates by more than three orders of magnitude. The detector has an almost infinite photon counting dynamic range and exhibits superior spatial resolution when compared to present crystallographic phosphor imaging plates or phosphor coupled CCD detectors. The detector is a high resistivity N-type Si with a pixel pitch of 150x150 mu m, and a thickness of 300 mu m, and is bump bonded to an application specific integrated circuit. The event driven readout of the detector is based on the column architecture and allows an independent pixel hit rate above 1 million photons/s/pixel. The device provides energy discrimination and sparse data readout which yields minimal dead-time. This type of architecture allows a continuous (frameless) data acquisition, a f...

  10. Integration and installation of the CMS pixel barrel detector

    CERN Document Server

    Kastli, Hans-Christian

    2008-01-01

    A 66 million pixel detector has been installed in 2008 into the CMS experiment at CERN. The development and construction time took more than 10 years. In this paper the assembly of the barrel detector is described. A simple but effective method to accomplish a survey of the module positions during assembly is discussed. Furthermore the insertion and commissioning of the CMS pixel barrel detector which took place in July 2008 is illustrated.

  11. Discrimination of alpha particles in CdZnTe detectors with coplanar grid for the COBRA experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rebber, Henning [Universitaet Hamburg, Institut fuer Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Collaboration: COBRA-Collaboration

    2016-07-01

    The aim of the COBRA experiment is the search for neutrinoless double beta decay using CdZnTe semiconductor detectors. A background rate in the order of 10{sup -3} counts per keV, kg and year is intended in order to be sensitive to a half-life larger than 10{sup 26} years. Measurements from a demonstrator setup and Monte Carlo simulations indicate that a large background component is due to alpha particles. These generate charge clouds of only few μm in diameter in the detector, leading to characteristic pulse features. Parameter-based cut criteria were developed to discriminate alpha events by means of their pulse shapes. The cuts were tested on data from alpha and beta irradiation of a (1 x 1 x 1) cm{sup 3} CdZnTe detector with coplanar grid. The pulse shapes of all event signals were read out by FADCs with a sampling rate of 100 MHz. The signals were reproduced by a detector simulation which hence was used to study the cuts for energies up to 3 MeV and different detector regions.

  12. Status of the CMS Phase I pixel detector upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Spannagel, S., E-mail: simon.spannagel@desy.de

    2016-09-21

    A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip.

  13. Status of the CMS Phase I Pixel Detector Upgrade

    CERN Document Server

    Spannagel, Simon

    2016-09-21

    A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase~I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a significantly reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These improvements allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. This contribution gives an overview of the design of the upgraded pixel detector and the status of the upgrade project, and presents test beam performance measurements of the production read-out chip.

  14. Small Pixel Hybrid CMOS X-ray Detectors

    Science.gov (United States)

    Hull, Samuel; Bray, Evan; Burrows, David N.; Chattopadhyay, Tanmoy; Falcone, Abraham; Kern, Matthew; McQuaide, Maria; Wages, Mitchell

    2018-01-01

    Concepts for future space-based X-ray observatories call for a large effective area and high angular resolution instrument to enable precision X-ray astronomy at high redshift and low luminosity. Hybrid CMOS detectors are well suited for such high throughput instruments, and the Penn State X-ray detector lab, in collaboration with Teledyne Imaging Sensors, has recently developed new small pixel hybrid CMOS X-ray detectors. These prototype 128x128 pixel devices have 12.5 micron pixel pitch, 200 micron fully depleted depth, and include crosstalk eliminating CTIA amplifiers and in-pixel correlated double sampling (CDS) capability. We report on characteristics of these new detectors, including the best read noise ever measured for an X-ray hybrid CMOS detector, 5.67 e- (RMS).

  15. Construction and Tests of Modules for the ATLAS Pixel Detector

    CERN Document Server

    AUTHOR|(CDS)2068490

    2003-01-01

    The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system and will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the pixel detector near the interaction point requires excellent radiation hardness, mechanical and thermal robustness, good long-term stability, all combined with a low material budget. The pre-production phase of such pixel modules has nearly finished, yielding fully functional modules. Results are presented of tests with these modules.

  16. Performance of CdZnTe strip detectors as sub-millimeter resolution imaging gamma radiation spectrometers

    International Nuclear Information System (INIS)

    Mayer, M.; Boykin, D.V.; Drake, A.

    1996-01-01

    We report γ-ray detection performance measurements and computer simulations of a sub-millimeter pitch CdZnTe strip detector. The detector is a prototype for γ-ray astronomy measurements in the range of 20-200 keV. The prototype is a 1.5 mm thick, 64 x 64 orthogonal stripe CdZnTe detector of 0.375 mm pitch in both dimensions, with approximately one square inch of sensitive area. Using discrete laboratory electronics to process signals from 8 x 8 stripe region of the prototype we measured good spectroscopic uniformity and sub-pitch (∼ 0.2 mm) spatial resolution in both x and y dimensions. We present below measurements of the spatial uniformity, relative timing and pulse height of the anode and cathode signals, and the photon detection efficiency. We also present a technique for determining the location of the event in the third dimension (depth). We simulated the photon interactions and signal generation in the strip detector and the test electronics and we compare these results with the data. The data indicate that cathode signal - as well as the anode signal - arises more strongly from the conduction electrons rather than the holes

  17. CdTe and CdZnTe detectors behavior in X-ray computed tomography conditions

    CERN Document Server

    Ricq, S; Garcin, M

    2000-01-01

    The application of CdTe and CdZnTe 2D array detectors for medical X-ray Computed Tomography (XCT) is investigated. Different metallic electrodes have been deposited on High-Pressure Bridgman Method CdZnTe and on Traveling Heater Method CdTe:Cl. These detectors are exposed to X-rays in the CT irradiation conditions and are characterized experimentally in current mode. Detectors performances such as sensitivity and response speed are studied. They are correlated with charge trapping and de-trapping. The trapped carrier space charges may influence the injection from the electrodes. This enables one to get information on the nature of the predominant levels involved. The performances achieved are encouraging: dynamic ranges higher than 4 decades and current decreases of 3 decades in 4 ms after X-ray beam cut-off are obtained. Nevertheless, these detectors are still limited by high trap densities responsible for the memory effect that makes them unsuitable for XCT.

  18. Current state-of-the-art industrial and research applications using room-temperature CdTe and CdZnTe solid state detectors

    International Nuclear Information System (INIS)

    Eisen, Y.

    1996-01-01

    Improvements of CdTe crystal quality and significant progress in the growth of large ingots of high resistivity CdZnTe material enable the fabrication of larger area detectors in single element form or monolithic arrays. These advances allow for the development of imaging devices of improved spatial resolution for industrial, research and medical applications. CdTe and CdZnTe detectors operate in single photon counting mode or in current mode (charge integrating mode). The paper presents advantages of CdTe and CdZnTe over common scintillator type detectors, but also presents the shortcomings of the former detectors with respect to charge collection which limit the yields of good spectrometers. The paper reviews industrial and research applications utilizing these detectors and in particular describes in detail two imaging systems for security screening and custom inspection. These systems are characterized by large dynamic range and good spatial resolution and are composed of large arrays of CdTe spectrometers and discriminator grade detectors. A wide energy range detector assembly, for astrophysical research of gamma ray bursts composed of CdTe, HgI 2 and CdZnTe spectrometers in two dimensional arrays is also presented. (orig.)

  19. Diamond and silicon pixel detectors in high radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Jieh-Wen

    2012-10-15

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

  20. Diamond and silicon pixel detectors in high radiation environments

    International Nuclear Information System (INIS)

    Tsung, Jieh-Wen

    2012-10-01

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10 16 particles per cm 2 , which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10 15 particles per cm 2 .

  1. Online calibrations and performance of the ATLAS Pixel Detector

    CERN Document Server

    Keil, M; The ATLAS collaboration

    2010-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. It consists of 1744 silicon sensors equipped with approximately 80 M electronic channels, providing typically three measurement points with high resolution for particles emerging from the beam-interaction region, thus allowing measuring particle tracks and secondary vertices with very high precision. The readout system of the Pixel Detector is based on a bi-directional optical data transmission system between the detector and the data acquisition system with an individual link for each of the 1744 modules. Signal conversion components are located on both ends, approximately 80 m apart. The talk will give an overview of the calibration and performance of both the detector and its optical readout. The most basic parameter to be tuned and calibrated for the detector electronics is the readout threshold of the individual pixel channels. These need to be carefully tuned to optimise position resolution a...

  2. New pixelized Micromegas detector for the COMPASS experiment

    International Nuclear Information System (INIS)

    Neyret, D; Anfreville, M; Bedfer, Y; Burtin, E; D'Hose, N; Giganon, A; Kunne, F; Magnon, A; Marchand, C; Paul, B; Platchkov, S; Vandenbroucke, M; Ketzer, B; Konorov, I

    2009-01-01

    New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm 2 , 10 times larger than for the present detectors) with pixelized read-out in the central part, light and integrated electronics, and improved robustness. Studies were done with the present detectors moved in the beam, and two first pixelized prototypes are being tested with muon and hadron beams in real conditions at COMPASS. We present here this new project and report on two series of tests, with old detectors moved into the beam and with pixelized prototypes operated in real data taking condition with both muon and hadron beams.

  3. Design of low noise front-end ASIC and DAQ system for CdZnTe detector

    International Nuclear Information System (INIS)

    Luo Jie; Deng Zhi; Liu Yinong

    2012-01-01

    A low noise front-end ASIC has been designed for CdZnTe detector. This chip contains 16 channels and each channel consists of a dual-stage charge sensitive preamplifier, 4th order semi-Gaussian shaper, leakage current compensation (LCC) circuit, discriminator and output buffer. This chip has been fabricated in Chartered 0.35 μm CMOS process, the preliminary results show that it works well. The total channel charge gain can be adjusted from 100 mV/fC to 400 mV/fC and the peaking time can be adjusted from 1 μs to 4 μs. The minimum measured ENC at zero input capacitance is 70 e and minimum noise slope is 20 e/pF. The peak detector and derandomizer (PDD) ASIC developed by BNL and an associated USB DAQ board are also introduced in this paper. Two front-end ASICs can be connected to the PDD ASIC on the USB DAQ board and compose a 32 channels DAQ system for CdZnTe detector. (authors)

  4. The pin pixel detector--X-ray imaging

    CERN Document Server

    Bateman, J E; Derbyshire, G E; Duxbury, D M; Marsh, A S; Simmons, J E; Stephenson, R

    2002-01-01

    The development and testing of a soft X-ray gas pixel detector, which uses connector pins for the anodes is reported. Based on a commercial 100 pin connector block, a prototype detector of aperture 25.4 mm centre dot 25.4 mm can be economically fabricated. The individual pin anodes all show the expected characteristics of small gas detectors capable of counting rates reaching 1 MHz per pin. A 2-dimensional resistive divide readout system has been developed to permit the imaging properties of the detector to be explored in advance of true pixel readout electronics.

  5. SLHC upgrade plans for the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Sicho, Petr

    2009-01-01

    The ATLAS pixel detector is an 80 million channels silicon tracking system designed to detect charged tracks and secondary vertices with very high precision. An upgrade of the ATLAS pixel detector is presently being considered, enabling to cope with higher luminosity at Super Large Hadron Collider (SLHC). The increased luminosity leads to extremely high radiation doses in the innermost region of the ATLAS tracker. Options considered for a new detector are discussed, as well as some important R and D activities, such as investigations towards novel detector geometries and novel processes.

  6. Geometry simulation and physics with the CMS forward pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Parashar, N [Purdue University Calumet, Hammond, Indiana (United States)], E-mail: Neeti@fnal.gov

    2008-06-15

    The Forward Pixel Detector of CMS is an integral part of the Tracking system, which will play a key role in addressing the full physics potential of the collected data. It has a very complex geometry that encompasses multilayer structure of its detector modules. This presentation describes the development of geometry simulation for the Forward Pixel Detector. A new geometry package has been developed, which uses the detector description database (DDD) interface for the XML (eXtensive Markup Language) to GEANT simulation. This is necessary for digitization and GEANT4 reconstruction software for tracking. The expected physics performance is also discussed.

  7. Geometry simulation and physics with the CMS forward pixel detector

    International Nuclear Information System (INIS)

    Parashar, N

    2008-01-01

    The Forward Pixel Detector of CMS is an integral part of the Tracking system, which will play a key role in addressing the full physics potential of the collected data. It has a very complex geometry that encompasses multilayer structure of its detector modules. This presentation describes the development of geometry simulation for the Forward Pixel Detector. A new geometry package has been developed, which uses the detector description database (DDD) interface for the XML (eXtensive Markup Language) to GEANT simulation. This is necessary for digitization and GEANT4 reconstruction software for tracking. The expected physics performance is also discussed

  8. The hardware of the ATLAS Pixel Detector Control System

    International Nuclear Information System (INIS)

    Henss, T; Andreani, A; Boek, J; Boyd, G; Citterio, M; Einsweiler, K; Kersten, S; Kind, P; Lantzsch, K; Latorre, S; Maettig, P; Meroni, C; Sabatini, F; Schultes, J

    2007-01-01

    The innermost part of the ATLAS (A Toroidal LHC ApparatuS) experiment, which is currently under construction at the LHC (Large Hadron Collider), will be a silicon pixel detector comprised of 1744 individual detector modules. To operate these modules, the readout electronics, and other detector components, a complex power supply and control system is necessary. The specific powering and control requirements, as well as the custom made components of our power supply and control systems, are described. These include remotely programmable regulator stations, the power supply system for the optical transceivers, several monitoring units, and the Interlock System. In total, this comprises the Pixel Detector Control System (DCS)

  9. Silicon Pixel Detectors for Synchrotron Applications

    CERN Document Server

    Stewart, Graeme Douglas

    Recent advances in particle accelerators have increased the demands being placed on detectors. Novel detector designs are being implemented in many different areas including, for example, high luminosity experiments at the LHC or at next generation synchrotrons. The purpose of this thesis was to characterise some of these novel detectors. The first of the new detector types is called a 3D detector. This design was first proposed by Parker, Kenney and Segal (1997). In this design, doped electrodes are created that extend through the silicon substrate. When compared to a traditional photodiode with electrodes on the opposing surfaces, the 3D design can combine a reasonable detector thickness with a small electrode spacing resulting in fast charge collection and limited charge sharing. The small electrode spacing leads to the detectors having lower depletion voltages. This, combined with the fast collection time, makes 3D detectors a candidate for radiation hard applications. These applications include the upgra...

  10. Vertex measurement at a hadron collider. The ATLAS pixel detector

    International Nuclear Information System (INIS)

    Grosse-Knetter, J.

    2008-03-01

    The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system and will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical sensor-chip-hybrid modules, arranged in three barrels in the centre and three disks on either side for the forward region. The position of the Pixel Detector near the interaction point requires excellent radiation hardness, fast read-out, mechanical and thermal robustness, good long-term stability, all combined with a low material budget. The new design concepts used to meet the challenging requirements are discussed with their realisation in the Pixel Detector, followed by a description of a refined and extensive set of measurements to assess the detector performance during and after its construction. (orig.)

  11. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Nachman, Benjamin Philip; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of $10^{15}$ 1 MeV $n_\\mathrm{eq}/\\mathrm{cm}^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This talk presents a digitization model that includes radiation damage effects to the ATLAS Pixel sensors for the first time. After a thorough description of the setup, predictions for basic Pixel cluster properties are presented alongside first validation studies with Run 2 collision data.

  12. Integration of the CMS Phase 1 Pixel Detector

    CERN Document Server

    Kornmayer, Andreas

    2018-01-01

    During the extended year-end technical stop 2016/17 the CMS Pixel Detector has been replaced. The new Phase 1 Pixel Detector is designed for a luminosity that could exceed $\\text{L} = 2x10^{34} cm^{−2}s^{−1}$. With one additional layer in the barrel and the forward region of the new detector, combined with the higher hit rates as the LHC luminosity increases, these conditions called for an upgrade of the data acquisition system, which was realised based on the $\\mu$TCA standard. This contribution focuses on the experiences with integration of the new detector readout and control system and reports on the operational performance of the CMS Pixel detector.

  13. Design and Performance of the CMS Pixel Detector Readout Chip

    CERN Document Server

    Kästli, H C; Erdmann, W; Hörmann, C; Horisberger, R P; Kotlinski, D; Meier, B; Hoermann, Ch.

    2006-01-01

    The readout chip for the CMS pixel detector has to deal with an enormous data rate. On-chip zero suppression is inevitable and hit data must be buffered locally during the latency of the first level trigger. Dead-time must be kept at a minimum. It is dominated by contributions coming from the readout. To keep it low an analog readout scheme has been adopted where pixel addresses are analog coded. We present the architecture of the final CMS pixel detector readout chip with special emphasis on the analog readout chain. Measurements of its performance are discussed.

  14. Operational Experience with the ATLAS Pixel Detector at LHC

    CERN Document Server

    Keil, M

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus crucial for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via front-end chips bump-bonded to 1744 n-on-n silicon substrates. In this paper results from the successful operation of the Pixel Detector at the LHC will be presented, including calibration procedures, detector performance and measurements of radiation damage. The detector performance is excellent: more than 95% of the pixels are operational, noise occupancy and hit efficiency exceed the des...

  15. Characterization of active CMOS sensors for capacitively coupled pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Hirono, Toko; Gonella, Laura; Janssen, Jens; Hemperek, Tomasz; Huegging, Fabian; Krueger, Hans; Wermes, Norbert [Institute of Physics, University of Bonn (Germany); Peric, Ivan [Institut fuer Prozessdatenverarbeitung und Elektronik, Karlsruher Institut fuer Technologie, Karlsruhe (Germany)

    2015-07-01

    Active CMOS pixel sensor is one of the most attractive candidates for detectors of upcoming particle physics experiments. In contrast to conventional sensors of hybrid detectors, signal processing circuit can be integrated in the active CMOS sensor. The characterization and optimization of the pixel circuit are indispensable to obtain a good performance from the sensors. The prototype chips of the active CMOS sensor were fabricated in the AMS 180nm and L-Foundry 150 nm CMOS processes, respectively a high voltage and high resistivity technology. Both chips have a charge sensitive amplifier and a comparator in each pixel. The chips are designed to be glued to the FEI4 pixel readout chip. The signals from 3 pixels of the prototype chips are capacitively coupled to the FEI4 input pads. We have performed lab tests and test beams to characterize the prototypes. In this presentation, the measurement results of the active CMOS prototype sensors are shown.

  16. Recent advances in Tl Br, Cd Te and CdZnTe semiconductor radiation detectors: a review

    International Nuclear Information System (INIS)

    Oliveira, Icimone B.

    2011-01-01

    The success in the development of radiation spectrometers operating at room temperature is based on many years of effort on the part of large numbers of workers around the world. These individuals have contributed to the understanding of the fundamental materials issues associated with the growth of semiconductors for this application, the development of device fabrication and processing technology, and advances in low noise electronics and pulse processing. Progress in this field continues at an accelerated pace, as in evidenced by the improvements in detector performance and by the growing number of commercial products. Thus, the last years have been seen continued effort in the development of room temperature compound semiconductors devices. High-Z compound semiconductor detectors has been explored for high energy resolution, high detection efficiency and are of low cost. Compound semiconductors detectors are well suited for addressing needs of demanding applications such as bore hole logging where high operating temperature are encountered. In this work recent developments in semiconductors detectors were reviewed. This review concentrated on thallium bromide (TlBr), cadmium zinc telluride (CdZnTe) and cadmium telluride (CdTe) crystals detectors. TlBr has higher stopping power compared to common semiconductor materials because it has the higher photoelectric and total attenuation coefficients over wide energy range from 100 keV to 1 MeV. CdTe and CdZnTe detectors have several attractive features for detecting X-ray and low energy gamma ray. Their relatively large band gaps lead to a relatively low leakage current and offer an excellent energy resolution at room temperature. A literature survey and bibliography was also included. (author)

  17. Recent advances in Tl Br, Cd Te and CdZnTe semiconductor radiation detectors: a review

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Icimone B. [Universidade Bandeirante (UNIBAN), Sao Paulo, SP (Brazil)

    2011-07-01

    The success in the development of radiation spectrometers operating at room temperature is based on many years of effort on the part of large numbers of workers around the world. These individuals have contributed to the understanding of the fundamental materials issues associated with the growth of semiconductors for this application, the development of device fabrication and processing technology, and advances in low noise electronics and pulse processing. Progress in this field continues at an accelerated pace, as in evidenced by the improvements in detector performance and by the growing number of commercial products. Thus, the last years have been seen continued effort in the development of room temperature compound semiconductors devices. High-Z compound semiconductor detectors has been explored for high energy resolution, high detection efficiency and are of low cost. Compound semiconductors detectors are well suited for addressing needs of demanding applications such as bore hole logging where high operating temperature are encountered. In this work recent developments in semiconductors detectors were reviewed. This review concentrated on thallium bromide (TlBr), cadmium zinc telluride (CdZnTe) and cadmium telluride (CdTe) crystals detectors. TlBr has higher stopping power compared to common semiconductor materials because it has the higher photoelectric and total attenuation coefficients over wide energy range from 100 keV to 1 MeV. CdTe and CdZnTe detectors have several attractive features for detecting X-ray and low energy gamma ray. Their relatively large band gaps lead to a relatively low leakage current and offer an excellent energy resolution at room temperature. A literature survey and bibliography was also included. (author)

  18. Challenges of small-pixel infrared detectors: a review.

    Science.gov (United States)

    Rogalski, A; Martyniuk, P; Kopytko, M

    2016-04-01

    In the last two decades, several new concepts for improving the performance of infrared detectors have been proposed. These new concepts particularly address the drive towards the so-called high operating temperature focal plane arrays (FPAs), aiming to increase detector operating temperatures, and as a consequence reduce the cost of infrared systems. In imaging systems with the above megapixel formats, pixel dimension plays a crucial role in determining critical system attributes such as system size, weight and power consumption (SWaP). The advent of smaller pixels has also resulted in the superior spatial and temperature resolution of these systems. Optimum pixel dimensions are limited by diffraction effects from the aperture, and are in turn wavelength-dependent. In this paper, the key challenges in realizing optimum pixel dimensions in FPA design including dark current, pixel hybridization, pixel delineation, and unit cell readout capacity are outlined to achieve a sufficiently adequate modulation transfer function for the ultra-small pitches involved. Both photon and thermal detectors have been considered. Concerning infrared photon detectors, the trade-offs between two types of competing technology-HgCdTe material systems and III-V materials (mainly barrier detectors)-have been investigated.

  19. Development of pixel detectors for SSC vertex tracking

    International Nuclear Information System (INIS)

    Kramer, G.; Shapiro, S.L.; Arens, J.F.; Jernigan, J.G.; Skubic, P.

    1991-04-01

    A description of hybrid PIN diode arrays and a readout architecture for their use as a vertex detector in the SSC environment is presented. Test results obtained with arrays having 256 x 256 pixels, each 30 μm square, are also presented. The development of a custom readout for the SSC will be discussed, which supports a mechanism for time stamping hit pixels, storing their xy coordinates, and storing the analog information within the pixel. The peripheral logic located on the array, permits the selection of those pixels containing interesting data and their coordinates to be selectively read out. This same logic also resolves ambiguous pixel ghost locations and controls the pixel neighbor read out necessary to achieve high spatial resolution. The thermal design of the vertex tracker and the proposed signal processing architecture will also be discussed. 5 refs., 13 figs., 3 tabs

  20. Fabrication of ATLAS pixel detector prototypes at IRST

    International Nuclear Information System (INIS)

    Boscardin, M.; Betta, G.-F. Dalla; Gregori, P.; Zen, M.; Zorzi, N.

    2001-01-01

    We report on the development of a fabrication technology for n-on-n silicon pixel detectors oriented to the ATLAS experiment at LHC. The main processing issues and some selected results from the electrical characterization of detector prototypes and related test structures are presented and discussed

  1. A gas pixel detector for X-ray imaging

    International Nuclear Information System (INIS)

    Bateman, J.E.; Connolly, J.F.

    1991-11-01

    A simple, robust form of gas pixel detector is discussed which is based on the use of electronic connector pins as the gain elements. With a rate capability of >10 5 counts/s per pin, an X-ray imaging detector system capable of counting at global rates of the order of 10 10 counts/s is foreseen. (author)

  2. A low mass pixel detector upgrade for CMS

    CERN Document Server

    Kästli, H C

    2010-01-01

    The CMS pixel detector has been designed for a peak luminosity of 10^34cm-2s-1 and a total dose corresponding to 2 years of LHC operation at a radius of 4 cm from the interaction region. Parts of the pixel detector will have to be replaced until 2015. The detector performance will be degraded for two reasons: radiation damage of the innermost layers and the planned increase of the LHC peak luminosity by a factor of 2-3. Based on the experience in planning, constructing and commissioning of the present pixel detector, we intend to upgrade the whole pixel detector in 2015. The main focus is on lowering the material budget and adding more tracking points. We will present the design of a new low mass pixel system consisting of 4 barrel layers and 3 end cap disks on each side. The design comprises of thin detector modules and a lightweight mechanical support structure using CO2 cooling. In addition, large efforts have been made to move material from the services out of the tracking region.

  3. Evaluation the image obtained from X-ray flat-panel detectors utilizing a polycrystalline CdZnTe film as the conversion layer

    International Nuclear Information System (INIS)

    Tokuda, S.; Kishihara, H.; Kaino, M.; Sato, T.

    2006-01-01

    We can expect that fluoroscopic images with a high sensitivity and excellent detective efficiency can be obtained by using a semiconductor with a small W factor for the conversion layer of X-ray flat-panel detectors, which have experienced a rapid gain inpopularity for medical and non-destructive industrial inspection uses in recent years. We believe that polycrystalline CdZnTe film formed by the closed spaced sublimation (CSS) method is a promising conversion material for next-generation high efficiency X-ray flat-panel detectors, and have previously reported the results of feasibility studies. In this paper, we present an overview of X-ray flat-panel detectors and the features of CdZnTe film, then we describe the CSS method of deposition and evaluation of the physical characteristics of CdZnTe film, and finally we present the results of our fabrication and testing of proto-type detectors utilizing CdZnTe film. (author)

  4. Operational Experience and Performance with the ATLAS Pixel detector

    CERN Document Server

    Martin, Christopher Blake; The ATLAS collaboration

    2018-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of $1.3\\times10^{34}\\text{cm}^{{-2}}\\text{s}^{{-1}}$ recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarized, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described, with special emphasis to radiation damage experience.

  5. Operational Experience and Performance with the ATLAS Pixel detector

    CERN Document Server

    Martin, Christopher Blake; The ATLAS collaboration

    2018-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of 1.3 x 10^34 cm-2 s-1 recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described, with special emphasis to radiation damage experience.

  6. First large DEPFET pixel modules for the Belle II Pixel Detector

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Felix; Avella, Paola; Kiesling, Christian; Koffmane, Christian; Moser, Hans-Guenther; Valentan, Manfred [Max-Planck-Institut fuer Physik, Muenchen (Germany); Andricek, Ladislav; Richter, Rainer [Halbleiterlabor der Max-Planck-Gesellschaft, Muenchen (Germany); Collaboration: Belle II-Collaboration

    2016-07-01

    DEPFET pixel detectors offer excellent signal to noise ratio, resolution and low power consumption with a low material budget. They will be used at Belle II and are a candidate for an ILC vertex detector. The pixels are integrated in a monolithic piece of silicon which also acts as PCB providing the signal and control routings for the ASICs on top. The first prototype DEPFET sensor modules for Belle II have been produced. The modules have 192000 pixels and are equipped with SMD components and three different kinds of ASICs to control and readout the pixels. The entire readout chain has to be studied; the metal layer interconnectivity and routings need to be verified. The modules are fully characterized, and the operation voltages and control sequences of the ASICs are investigated. An overview of the DEPFET concept and first characterization results is presented.

  7. Rework of flip chip bonded radiation pixel detectors

    International Nuclear Information System (INIS)

    Vaehaenen, S.; Heikkinen, H.; Pohjonen, H.; Salonen, J.; Savolainen-Pulli, S.

    2008-01-01

    In this paper, some practical aspects of reworking flip chip hybridized pixel detectors are discussed. As flip chip technology has been advancing in terms of placement accuracy and reliability, large-area hybrid pixel detectors have been developed. The area requirements are usually fulfilled by placing several readout chips (ROCs) on single sensor chip. However, as the number of ROCs increases, the probability of failure in the hybridization process and the ROC operation also increases. Because high accuracy flip chip bonding takes time, a significant part of the price of a pixel detector comes from the flip chip assembly process itself. As large-area detector substrates are expensive, and many flip chip placements are required, the price of an assembled detector can become very high. In a typical case, there is just one bad ROC (out of several) on a faulty detector to be replaced. Considering the high price of pixel detectors and the fact that reworking faulty ROCs does not take much longer than the original placement, it is worthwhile to investigate the feasibility of a rework process

  8. Rework of flip chip bonded radiation pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Vaehaenen, S. [VTT MEMS and Micropackaging, Espoo 02150 (Finland)], E-mail: sami.vahanen@vtt.fi; Heikkinen, H.; Pohjonen, H.; Salonen, J.; Savolainen-Pulli, S. [VTT MEMS and Micropackaging, Espoo 02150 (Finland)

    2008-06-11

    In this paper, some practical aspects of reworking flip chip hybridized pixel detectors are discussed. As flip chip technology has been advancing in terms of placement accuracy and reliability, large-area hybrid pixel detectors have been developed. The area requirements are usually fulfilled by placing several readout chips (ROCs) on single sensor chip. However, as the number of ROCs increases, the probability of failure in the hybridization process and the ROC operation also increases. Because high accuracy flip chip bonding takes time, a significant part of the price of a pixel detector comes from the flip chip assembly process itself. As large-area detector substrates are expensive, and many flip chip placements are required, the price of an assembled detector can become very high. In a typical case, there is just one bad ROC (out of several) on a faulty detector to be replaced. Considering the high price of pixel detectors and the fact that reworking faulty ROCs does not take much longer than the original placement, it is worthwhile to investigate the feasibility of a rework process.

  9. Operational experience of ATLAS SCT and Pixel Detector

    CERN Document Server

    Kocian, Martin; The ATLAS collaboration

    2017-01-01

    The ATLAS Inner Detector based on silicon sensors is consisting of a strip detector (SCT) and a pixel detector. It is the crucial component for vertexing and tracking in the ATLAS experiment. With the excellent performance of the LHC well beyond the original specification the silicon tracking detectors are facing substantial challenges in terms of data acquisition, radiation damage to the sensors, and SEUs in the readout ASICs. The approaches on how the detector systems cope with the demands of high luminosity operation while maintaining excellent performance through hardware upgrades, software and firmware algorithms, and operational settings, are presented.

  10. Fully integrated CMOS pixel detector for high energy particles

    International Nuclear Information System (INIS)

    Vanstraelen, G.; Debusschere, I.; Claeys, C.; Declerck, G.

    1989-01-01

    A novel type of position and energy sensitive, monolithic pixel array with integrated readout electronics is proposed. Special features of the design are a reduction of the number of output channels and of the amount of output data, and the use of transistors on the high resistivity silicon. The number of output channels for the detector array is reduced by handling in parallel a number of pixels, chosen as a function of the time resolution required for the system, and by the use of an address decoder. A further reduction of data is achieved by reading out only those pixels which have been activated. The pixel detector circuit will be realized in a 3 μm p-well CMOS process, which is optimized for the full integration of readout electronics and detector diodes on high resistivity Si. A retrograde well is formed by means of a high energy implantation, followed by the appropriate temperature steps. The optimization of the well shape takes into account the high substrate bias applied during the detector operation. The design is largely based on the use of MOS transistors on the high resistivity silicon itself. These have proven to perform as well as transistors on standard doped substrate. The basic building elements as well as the design strategy of the integrated pixel detector are presented in detail. (orig.)

  11. Initial Measurements on Pixel Detector Modules for the ATLAS Upgrades

    CERN Document Server

    Gallrapp, C; The ATLAS collaboration

    2011-01-01

    Delicate conditions in terms of peak and integrated luminosity in the Large Hadron Collider (LHC) will raise the ATLAS Pixel Detector to its performance limits. Silicon planar, silicon 3D and diamond pixel sensors are three possible sensor technologies which could be implemented in the upcoming Pixel Detector upgrades of the ATLAS experiment. Measurements of the IV-behavior and measurements with radioactive Americium-241 and Strontium-90 are used to characterize the sensor properties and to understand the interaction between the ATLAS FE-I4 front-end chip and the sensor. Comparisons of results from before and after irradiation for silicon planar and 3D pixel sensors, which give a first impression on the charge collection properties of the different sensor technologies, are presented.

  12. Gamma spectrometric characterization of short cooling time nuclear spent fuels using hemispheric CdZnTe detectors

    CERN Document Server

    Lebrun, A; Szabó, J L; Arenas-Carrasco, J; Arlt, R; Dubreuil, A; Esmailpur-Kazerouni, K

    2000-01-01

    After years of cooling, nuclear spent fuel gamma emissions are mainly due to caesium isotopes which are emitters at 605, 662 and 796-801 keV. Extensive work has been done on such fuels using various CdTe or CdZnTe probes. When fuels have to be measured after short cooling time (during NPP outage) the spectrum is much more complex due to the important contributions of niobium and zirconium in the 700 keV range. For the first time in a nuclear power plant, four spent fuels of the Kozloduy VVER reactor no 4 were measured during outage, 37 days after shutdown of the reactor. In such conditions, good resolution is of particular interest, so a 20 mm sup 3 hemispheric crystal was used with a resolution better than 7 keV at 662 keV. This paper presents the experimental device and analyzes the results which show that CdZnTe commercially available detectors enabled us to perform a semi-quantitative determination of the burn-up after a short cooling time. In addition, it is discussed how a burn-up evolution code (CESAR)...

  13. Results from the commissioning of the ATLAS Pixel Detector

    CERN Document Server

    Masetti, L

    2008-01-01

    The Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. It is an 80 million channel silicon tracking system designed to detect charged tracks and secondary vertices with very high precision. After connection of cooling and services and verification of their operation, the ATLAS Pixel Detector is now in the final stage of its commissioning phase. Calibration of optical connections, verification of the analog performance and special DAQ runs for noise studies have been performed and the first tracks in combined operation with the other subdetectors of the ATLAS Inner Detector were observed. The results from calibration tests on the whole detector and from cosmic muon data are presented.

  14. Optical data links for the ATLAS SCT and Pixel Detector

    International Nuclear Information System (INIS)

    Gregor, I.M.; Weidberg, A.R.; Lee, S.C.; Chu, M.L.; Teng, P.K.

    2001-01-01

    ATLAS (The ATLAS Technical Proposal, CERN/LHCC 94-33) is one of the large electronic particle detectors at LHC (The LHC Conceptual Design, Report- The Yellow Book, CERN/AC/95-05(LHC)) which will become operational in 2005. It is planned to use radiation tolerant optical links for the data transfer from the SemiConductor Tracker (SCT) (ATLAS Inner Detector Technical Proposal, CERN/LHCC 97-16 and CERN/LHCC 97-17). and Pixel Detector (ATLAS Pixel Detector Technical Proposal, CERN/LHCC 98-13) systems to the acquisition electronics over a distance up to 140m. The overall architecture and the performance of these optical data links are described. One of the three candidate designs for an on-detector Opto-Package is presented

  15. Online Calibration and Performance of the ATLAS Pixel Detector

    CERN Document Server

    Keil, M

    2011-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. It consists of 1744 silicon sensors equipped with approximately 80 million electronic channels, providing typically three measurement points with high resolution for particles emerging from the beam-interaction region, thus allowing measuring particle tracks and secondary vertices with very high precision. The readout system of the Pixel Detector is based on a bi-directional optical data transmission system between the detector and the data acquisition system with an individual link for each of the 1744 modules. Signal conversion components are located on both ends, approximately 80 m apart. This paper describes the tuning and calibration of the optical links and the detector modules, including measurements of threshold, noise, charge measurement, timing performance and the sensor leakage current.

  16. Angular resolution of the gaseous micro-pixel detector Gossip

    Science.gov (United States)

    Bilevych, Y.; Blanco Carballo, V.; van Dijk, M.; Fransen, M.; van der Graaf, H.; Hartjes, F.; Hessey, N.; Koppert, W.; Nauta, S.; Rogers, M.; Romaniouk, A.; Veenhof, R.

    2011-06-01

    Gossip is a gaseous micro-pixel detector with a very thin drift gap intended for a high rate environment like at the pixel layers of ATLAS at the sLHC. The detector outputs not only the crossing point of a traversing MIP, but also the angle of the track, thus greatly simplifying track reconstruction. In this paper we describe a testbeam experiment to examine the angular resolution of the reconstructed track segments in Gossip. We used here the low diffusion gas mixture DME/CO 2 50/50. An angular resolution of 20 mrad for perpendicular tracks could be obtained from a 1.5 mm thin drift volume. However, for the prototype detector used at the testbeam experiment, the resolution of slanting tracks was worsened by poor time resolution of the pixel chip used.

  17. Angular resolution of the gaseous micro-pixel detector Gossip

    Energy Technology Data Exchange (ETDEWEB)

    Bilevych, Y.; Blanco Carballo, V.; Dijk, M. van; Fransen, M.; Graaf, H. van der; Hartjes, F.; Hessey, N.; Koppert, W.; Nauta, S. [Nikhef, P.O. Box 41882, 1009 DB Amsterdam (Netherlands); Rogers, M. [Radboud University, P.O. Box 9102, 6500HC Nijmegen (Netherlands); Romaniouk, A.; Veenhof, R. [CERN, CH-1211, Geneve 23 (Switzerland)

    2011-06-15

    Gossip is a gaseous micro-pixel detector with a very thin drift gap intended for a high rate environment like at the pixel layers of ATLAS at the sLHC. The detector outputs not only the crossing point of a traversing MIP, but also the angle of the track, thus greatly simplifying track reconstruction. In this paper we describe a testbeam experiment to examine the angular resolution of the reconstructed track segments in Gossip. We used here the low diffusion gas mixture DME/CO{sub 2} 50/50. An angular resolution of 20 mrad for perpendicular tracks could be obtained from a 1.5 mm thin drift volume. However, for the prototype detector used at the testbeam experiment, the resolution of slanting tracks was worsened by poor time resolution of the pixel chip used.

  18. Angular resolution of the gaseous micro-pixel detector Gossip

    International Nuclear Information System (INIS)

    Bilevych, Y.; Blanco Carballo, V.; Dijk, M. van; Fransen, M.; Graaf, H. van der; Hartjes, F.; Hessey, N.; Koppert, W.; Nauta, S.; Rogers, M.; Romaniouk, A.; Veenhof, R.

    2011-01-01

    Gossip is a gaseous micro-pixel detector with a very thin drift gap intended for a high rate environment like at the pixel layers of ATLAS at the sLHC. The detector outputs not only the crossing point of a traversing MIP, but also the angle of the track, thus greatly simplifying track reconstruction. In this paper we describe a testbeam experiment to examine the angular resolution of the reconstructed track segments in Gossip. We used here the low diffusion gas mixture DME/CO 2 50/50. An angular resolution of 20 mrad for perpendicular tracks could be obtained from a 1.5 mm thin drift volume. However, for the prototype detector used at the testbeam experiment, the resolution of slanting tracks was worsened by poor time resolution of the pixel chip used.

  19. Calibration Analysis Software for the ATLAS Pixel Detector

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00372086; The ATLAS collaboration

    2016-01-01

    The calibration of the ATLAS Pixel detector at LHC fulfils two main purposes: to tune the front-end configuration parameters for establishing the best operational settings and to measure the tuning performance through a subset of scans. An analysis framework has been set up in order to take actions on the detector given the outcome of a calibration scan (e.g. to create a mask for disabling noisy pixels). The software framework to control all aspects of the Pixel detector scans and analyses is called Calibration Console. The introduction of a new layer, equipped with new Front End-I4 Chips, required an update the Console architecture. It now handles scans and scans analyses applied together to chips with different characteristics. An overview of the newly developed Calibration Analysis Software will be presented, together with some preliminary result.

  20. Detector Modules for the CMS Pixel Phase 1 Upgrade

    CERN Document Server

    Zhu, De Hua; Berger, Pirmin; Meinhard, Maren Tabea; Starodumov, Andrey; Tavolaro, Vittorio Raoul

    2017-01-01

    The CMS Pixel phase 1 upgrade detector consists of 1184 modules with new design. An important part of the production is the module qualification and calibration, ensuring their proper functionality within the detector. This paper summarizes the qualification and calibration results of modules used in the innermost two detector layers with focus on methods using module-internal calibration signals. Extended characterizations on pixel level such as electronic noise and bump bond connectivity, optimization of operational parameters, sensor quality and thermal stress resistance were performed using a customized setup with controlled environment. It could be shown that the selected modules have on average $0.55 \\mathrm{ {}^{0\\!}\\!/\\!_{00} }\\, \\pm \\, 0.01 \\mathrm{ {}^{0\\!}\\!/\\!_{00} }\\,$ defective pixels and that all performance parameters stay within their specifications.

  1. Effects of Te inclusions on charge-carrier transport properties in CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Gu, Yaxu; Rong, Caicai; Xu, Yadong; Shen, Hao; Zha, Gangqiang; Wang, Ning; Lv, Haoyan; Li, Xinyi; Wei, Dengke; Jie, Wanqi

    2015-01-01

    Highlights: • This work reveals the behaviors of Te inclusion in affecting charge-carrier transport properties in CdZnTe detectors for the first time and analysis the mechanism therein. • The results show that charge collection efficiencies in Te inclusion degraded regions experience fast ascent under low biases and slow descent at high applied biases, which deviates from the Hecht rule. • This phenomenon is attributed to the competitive influence of two mechanisms under different biases, namely charge carrier trapping due to uniformly distributed point defects and Te inclusion induced transient charge loss. • A modified Hecht equation is further proposed to explain the effects of high-density localized defects, say Te inclusions, on the charge collection efficiency. • We believe that this research has wide appeal to analyze the macroscopic defects and their influence on charge transport properties in semiconductor radiation detectors. - Abstract: The influence of tellurium (Te) inclusions on the charge collection efficiency in cadmium zinc telluride (CdZnTe or CZT) detectors has been investigated using ion beam induced charge (IBIC) technique. Combining the analysis of infrared transmittance image, most of the low charge collection areas in the IBIC images prove the existence of Te inclusions. To further clarify the role of Te inclusions on charge transport properties, bias dependent local IBIC scan was performed on Te inclusion related regions from 20 V to 500 V. The result shows that charge collection efficiencies in Te inclusion degraded regions experience fast ascent under low biases and slow descent at high applied biases, which deviates from Hecht rule. This behavior is attributed to the competitive influence of two mechanisms under different biases, namely charge carrier trapping due to uniformly distributed point defects and Te inclusion induced transient charge loss. A modified Hecht equation is further proposed to explain the effects of high

  2. Gas Pixel Detectors for low energy X-ray polarimetry

    International Nuclear Information System (INIS)

    Spandre, Gloria

    2007-01-01

    Gas Pixel Detectors are position-sensitive proportional counters in which a complete integration between the gas amplification structure and the read-out electronics has been reached. Various generation of Application-Specific Integrated Circuit (ASIC) have been designed in deep submicron CMOS technology to realize a monolithic device which is at the same time the charge collecting electrode and the analog amplifying and charge measuring front-end electronics. The experimental response of a detector with 22060 pixels at 80 μm pitch to polarized and un-polarized X-ray radiation is shown and the application of this device for Astronomical X-ray Polarimetry discussed

  3. MCC: the Module Controller Chip for the ATLAS Pixel Detector

    International Nuclear Information System (INIS)

    Beccherle, R.; Darbo, G.; Gagliardi, G.; Gemme, C.; Morettini, P.; Musico, P.; Osculati, B.; Oppizzi, P.; Pratolongo, F.; Ruscino, E.; Schiavi, C.; Vernocchi, F.; Blanquart, L.; Einsweiler, K.; Meddeler, G.; Richardson, J.; Comes, G.; Fischer, P.; Calvet, D.; Boyd, R.; Sicho, P.

    2002-01-01

    In this article we describe the architecture of the Module Controller Chip for the ATLAS Pixel Detector. The project started in 1997 with the definition of the system specifications. A first fully-working rad-soft prototype was designed in 1998, while a radiation hard version was submitted in 2000. The 1998 version was used to build pixel detector modules. Results from those modules and from the simulated performance in ATLAS are reported. In the article we also describe the hardware/software tools developed to test the MCC performance at the LHC event rate

  4. New developments in clinical applications of CdTe and CdZnTe detectors

    International Nuclear Information System (INIS)

    Scheiber, C.

    1996-01-01

    This review about the medical applications of CdTe and CdZnTe is an update on the 1992 paper (1992). This new paper is legitimized by the recent progress which has been made in this field. First of all, the usefulness of a new material, i.e. CdZnTe, has been demonstrated. While the two materials are still being improved, it seems as yet too early to debate which of CdTe:Cl or CdZnTe will be the best choice. Historical applications span over the past 18 years, involving devices like miniature probes for per-operative scintigraphy or the monitoring of physiological functions and, closer to us, appliances dedicated to bone densitometry, and have been expanding as such devices have become commercially available, for many years now. Newly available microelectronic circuitry allows 2D-arrays to be built for digital quantitative X-ray (chest, dental..) and for high-resolution gamma cameras. The clinical demand is very high, especially in the field of nuclear medicine. Although there already exist clinical demonstrators, the future of such CdTe applications depends on further reduction in material and device mounting costs. New perspectives concern XCT applications, but the data resulting from research work are kept for restricted use within industrial R and D laboratories. (orig.)

  5. Results from the Commissioning of the ATLAS Pixel Detector

    CERN Document Server

    Ibragimov, I

    2008-01-01

    The ATLAS pixel detector is the innermost tracking detector of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN. It has a total active area of 1.7 m2 of silicon read out by approximately 80 million electronic channels, which will detect particle tracks and decay vertices with a very high precision. After more than 10 years of development and construction it is the first time ever the whole detector has been operated together. The paper will illustrate the detector performance and give first results from the combined ATLAS cosmics runs.

  6. Modeling of Pixelated Detector in SPECT Pinhole Reconstruction.

    Science.gov (United States)

    Feng, Bing; Zeng, Gengsheng L

    2014-04-10

    A challenge for the pixelated detector is that the detector response of a gamma-ray photon varies with the incident angle and the incident location within a crystal. The normalization map obtained by measuring the flood of a point-source at a large distance can lead to artifacts in reconstructed images. In this work, we investigated a method of generating normalization maps by ray-tracing through the pixelated detector based on the imaging geometry and the photo-peak energy for the specific isotope. The normalization is defined for each pinhole as the normalized detector response for a point-source placed at the focal point of the pinhole. Ray-tracing is used to generate the ideal flood image for a point-source. Each crystal pitch area on the back of the detector is divided into 60 × 60 sub-pixels. Lines are obtained by connecting between a point-source and the centers of sub-pixels inside each crystal pitch area. For each line ray-tracing starts from the entrance point at the detector face and ends at the center of a sub-pixel on the back of the detector. Only the attenuation by NaI(Tl) crystals along each ray is assumed to contribute directly to the flood image. The attenuation by the silica (SiO 2 ) reflector is also included in the ray-tracing. To calculate the normalization for a pinhole, we need to calculate the ideal flood for a point-source at 360 mm distance (where the point-source was placed for the regular flood measurement) and the ideal flood image for the point-source at the pinhole focal point, together with the flood measurement at 360 mm distance. The normalizations are incorporated in the iterative OSEM reconstruction as a component of the projection matrix. Applications to single-pinhole and multi-pinhole imaging showed that this method greatly reduced the reconstruction artifacts.

  7. Electron imaging with Medipix2 hybrid pixel detector

    International Nuclear Information System (INIS)

    McMullan, G.; Cattermole, D.M.; Chen, S.; Henderson, R.; Llopart, X.; Summerfield, C.; Tlustos, L.; Faruqi, A.R.

    2007-01-01

    The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 μmx55 μm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 μm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach ∼85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach ∼35% of that expected for a perfect detector (4/π 2 ). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/π). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected values for the MTF and DQE as a function of the threshold energy. The good agreement between theory and experiment allows suggestions for further improvements to be made with confidence. The present detector is already very useful for experiments that require a high DQE at very low doses

  8. Performance of the CMS Phase 1 Pixel Detector

    CERN Document Server

    Akgun, Bora

    2018-01-01

    It is anticipated that the LHC accelerator will reach and exceed the luminosity of L = 2$\\times$10$^{34}$cm$^{-2}$s$^{-1}$ during the LHC Run 2 period until 2023. At this higher luminosity and increased hit occupancies the CMS phase-0 pixel detector would have been subjected to severe dead time and inefficiencies introduced by limited buffers in the analog read-out chip and effects of radiation damage in the sensors. Therefore a new pixel detector has been built and replaced the phase-0 detector in the 2016/17 LHC extended year-end technical stop. The CMS phase-1 pixel detector features four central barrel layers and three end-cap disks in forward and backward direction for robust tracking performance, and a significantly reduced overall material budget including new cooling and powering schemes. The design of the new front-end readout chip comprises larger data buffers, an increased transmission bandwidth, and low-threshold comparators. These improvements allow the new pixel detector to sustain and improve t...

  9. Electron imaging with Medipix2 hybrid pixel detector.

    Science.gov (United States)

    McMullan, G; Cattermole, D M; Chen, S; Henderson, R; Llopart, X; Summerfield, C; Tlustos, L; Faruqi, A R

    2007-01-01

    The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 microm x 55 microm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 microm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach approximately 85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach approximately 35% of that expected for a perfect detector (4/pi(2)). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/pi). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected values for the MTF and DQE as a function of the threshold energy. The good agreement between theory and experiment allows suggestions for further improvements to be made with confidence. The present detector is already very useful for experiments that require a high DQE at very low doses.

  10. Results from the Commissioning of the ATLAS Pixel Detector

    CERN Document Server

    Strandberg, S

    2009-01-01

    The ATLAS pixel detector is a high resolution, silicon based, tracking detector with its innermost layer located only 5 cm away from the ATLAS interaction point. It is designed to provide good hit resolution and low noise, both important qualities for pattern recognition and for finding secondary vertices originating from decays of long-lived particles. The pixel detector has 80 million readout channels and is built up of three barrel layers and six disks, three on each side of the barrel. The detector was installed in the center of ATLAS in June 2007 and is currently being calibrated and commissioned. Details from the installation, commissioning and calibration are presented together with the current status.

  11. Test-beam results of a SOI pixel detector prototype

    CERN Document Server

    Bugiel, Roma; Dannheim, Dominik; Fiergolski, Adrian; Hynds, Daniel; Idzik, Marek; Kapusta, P; Kucewicz, Wojciech; Munker, Ruth Magdalena; Nurnberg, Andreas Matthias

    2018-01-01

    This paper presents the test-beam results of a monolithic pixel-detector prototype fabricated in 200 nm Silicon-On-Insulator (SOI) CMOS technology. The SOI detector was tested at the CERN SPS H6 beam line. The detector is fabricated on a 500 μm thick high-resistivity float- zone n-type (FZ-n) wafer. The pixel size is 30 μm × 30 μm and its readout uses a source- follower configuration. The test-beam data are analysed in order to compute the spatial resolution and detector efficiency. The analysis chain includes pedestal and noise calculation, cluster reconstruction, as well as alignment and η-correction for non-linear charge sharing. The results show a spatial resolution of about 4.3 μm.

  12. True coincidence-summing corrections for the coincident γ-rays measured with coplanar grid CdZnTe detectors

    International Nuclear Information System (INIS)

    Yuecel, H.; Solmaz, A.N.; Koese, E.; Bor, D.

    2010-01-01

    In this study, true coincidence-summing (TCS) correction factors have been measured for the sources 22 Na, 60 Co, 133 Ba and 152 Eu by use of three large volume coplanar grid CdZnTe (acronym: CZT) detectors. In case of a close-in detection geometry, two different TCS calculation algorithms were used to compute the required TCS correction factors. Both of the algorithms are based on the measured total-to-peak (TTP) ratio and full-energy peak (FEP) efficiency values that were obtained using almost 'single' energy and coincidence-free nuclides. The results for TCS correction factors obtained by two different algorithms were agreeable to each other. The obtained TCS factors were ranged from about 7% to 30.5% in a 2250 mm 3 CZT detector when a close counting geometry was used. For other two detectors with a volume of 1000 and 1687.5 mm 3 , the resulted TCS correction factors were relatively smaller and varied between about 0.1% and 20% at the close counting geometry condition. Therefore, the results indicate that there is a need for the estimation of TCS corrections in CZT detectors, especially when their crystal volumes are greater than 1 cm 3 and these detectors are used in the case of a close-in detection geometry.

  13. Performance verification of the CMS Phase-1 Upgrade Pixel detector

    Science.gov (United States)

    Veszpremi, V.

    2017-12-01

    The CMS tracker consists of two tracking systems utilizing semiconductor technology: the inner pixel and the outer strip detectors. The tracker detectors occupy the volume around the beam interaction region between 3 cm and 110 cm in radius and up to 280 cm along the beam axis. The pixel detector consists of 124 million pixels, corresponding to about 2 m 2 total area. It plays a vital role in the seeding of the track reconstruction algorithms and in the reconstruction of primary interactions and secondary decay vertices. It is surrounded by the strip tracker with 10 million read-out channels, corresponding to 200 m 2 total area. The tracker is operated in a high-occupancy and high-radiation environment established by particle collisions in the LHC . The current strip detector continues to perform very well. The pixel detector that has been used in Run 1 and in the first half of Run 2 was, however, replaced with the so-called Phase-1 Upgrade detector. The new system is better suited to match the increased instantaneous luminosity the LHC would reach before 2023. It was built to operate at an instantaneous luminosity of around 2×1034 cm-2s-1. The detector's new layout has an additional inner layer with respect to the previous one; it allows for more efficient tracking with smaller fake rate at higher event pile-up. The paper focuses on the first results obtained during the commissioning of the new detector. It also includes challenges faced during the first data taking to reach the optimal measurement efficiency. Details will be given on the performance at high occupancy with respect to observables such as data-rate, hit reconstruction efficiency, and resolution.

  14. Monitoring the Radiation Damage of the ATLAS Pixel Detector

    CERN Document Server

    Cooke, M; The ATLAS collaboration

    2012-01-01

    The Pixel Detector is the innermost charged particle tracking component employed by the ATLAS experiment at the CERN Large Hadron Collider (LHC). The instantaneous luminosity delivered by the LHC, now routinely in excess of 5x10^{33} cm^{-2} s^{-1}, results in a rapidly increasing accumulated radiation dose to the detector. Methods based on the sensor depletion properties and leakage current are used to monitor the evolution of the radiation damage, and results from the 2011 run are presented.

  15. Monitoring the radiation damage of the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Cooke, M.

    2013-01-01

    The pixel detector is the innermost charged particle tracking component employed by the ATLAS experiment at the CERN Large Hadron Collider (LHC). The instantaneous luminosity delivered by the LHC, now routinely in excess of 5×10 33 cm −2 s −1 , results in a rapidly increasing accumulated radiation dose to the detector. Methods based on the sensor depletion properties and leakage current are used to monitor the evolution of the radiation damage, and results from the 2011 run are presented

  16. Readout chip for the CMS pixel detector upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Rossini, Marco, E-mail: marco.rossini@phys.ethz.ch

    2014-11-21

    For the CMS experiment a new pixel detector is planned for installation during the extended shutdown in winter 2016/2017. Among the changes of the detector modified front end electronics will be used for higher efficiency at peak luminosity of the LHC and faster readout. The first prototype versions of the new readout chip have been designed and produced. The results of qualification and calibration for the new chip are presented in this paper.

  17. Detection of electron and hole traps in CdZnTe radiation detectors by thermoelectric emission spectroscopy and thermally stimulated conductivity

    International Nuclear Information System (INIS)

    Lee, E.Y.; Brunett, B.A.; Olsen, R.W.; Van Scyoc, J.M. III; Hermon, H.; James, R.B.

    1998-01-01

    The electrical properties of CdZnTe radiation detectors are largely determined by electron and hole traps in this material. The traps, in addition to degrading the detector performance, can function as dopants and determine the resistivity of the material. Thermoelectric emission spectroscopy and thermally stimulated conductivity are used to detect these traps in a commercially available spectrometer-grade CdZnTe detector, and the electrical resistivity is measured as a function of temperature. A deep electron trap having an energy of 695 meV and cross section of 8 x 10 -16 cm 2 is detected and three hole traps having energies of 70 ± 20 meV, 105 ± 30 meV and 694 ± 162 meV are detected. A simple model based on these traps explains quantitatively all the data, including the electrical properties at room temperature and also their temperature dependence

  18. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15} n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside...

  19. Monitoring radiation damage in the ATLAS pixel detector

    CERN Document Server

    Schorlemmer, André Lukas; Quadt, Arnulf; Große-Knetter, Jörn; Rembser, Christoph; Di Girolamo, Beniamino

    2014-11-05

    Radiation hardness is one of the most important features of the ATLAS pixel detector in order to ensure a good performance and a long lifetime. Monitoring of radiation damage is crucial in order to assess and predict the expected performance of the detector. Key values for the assessment of radiation damage in silicon, such as the depletion voltage and depletion depth in the sensors, are measured on a regular basis during operations. This thesis summarises the monitoring program that is conducted in order to assess the impact of radiation damage and compares it to model predictions. In addition, the physics performance of the ATLAS detector highly depends on the amount of disabled modules in the ATLAS pixel detector. A worrying amount of module failures was observed during run I. Thus it was decided to recover repairable modules during the long shutdown (LS1) by extracting the pixel detector. The impact of the module repairs and module failures on the detector performance is analysed in this thesis.

  20. Modeling radiation damage to pixel sensors in the ATLAS detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15}n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside ...

  1. Silicon Sensors for the Upgrades of the CMS Pixel Detector

    CERN Document Server

    Centis Vignali, Matteo; Schleper, Peter

    2015-01-01

    The Compact Muon Solenoid (CMS) is a general purpose detector at the Large Hadron Collider (LHC). The LHC luminosity is constantly increased through upgrades of the accel- erator and its injection chain. Two major upgrades will take place in the next years. The rst upgrade involves the LHC injector chain and allows the collider to achieve a luminosity of about 2 10 34 cm-2 s-1 A further upgrade of the LHC foreseen for 2025 will boost its luminosity to 5 10 34 cm-2 s1. As a consequence of the increased luminosity, the detectors need to be upgraded. In particular, the CMS pixel detector will undergo two upgrades in the next years. The rst upgrade (phase I) consists in the substitution of the current pixel detector in winter 2016/2017. The upgraded pixel detector will implement new readout elec- tronics that allow ecient data taking up to a luminosity of 2 10 34 cm-2s-1,twice as much as the LHC design luminosity. The modules that will constitute the upgraded detector are being produced at dierent institutes. Ham...

  2. Modeling radiation damage to pixel sensors in the ATLAS detector

    Science.gov (United States)

    Ducourthial, A.

    2018-03-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC) . As the closest detector component to the interaction point, these detectors will be subject to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC) [1], the innermost layers will receive a fluence in excess of 1015 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is essential in order to make accurate predictions for current and future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects on the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside early studies with LHC Run 2 proton-proton collision data.

  3. ATLAS Pixel Detector Design For HL-LHC

    CERN Document Server

    Smart, Ben; The ATLAS collaboration

    2016-01-01

    The ATLAS Inner Detector will be replaced for the High-Luminosity LHC (HL-LHC) running in 2026. The new Inner Detector will be called the Inner Tracker (ITk). The ITk will cover an extended eta-range: at least to |eta|<3.2, and likely up to |eta|<4.0. The ITk will be an all-Silicon based detector, consisting of a Silicon strip detector outside of a radius of 362mm, and a Silicon pixel detector inside of this radius. Several novel designs are being considered for the ITk pixel detector, to cope with high-eta charged particle tracks. These designs are grouped into 'extended' and 'inclined' design-types. Extended designs have long pixel staves with sensors parallel to the beamline. High-eta particles will therefore hit these sensors at shallow angles, leaving elongated charge clusters. The length of such a charge cluster can be used to estimate the angle of the passing particle. This information can then be used in track reconstruction to improve tracking efficiency and reduce fake rates. Inclined designs ...

  4. Performance of the INTPIX6 SOI pixel detector

    Science.gov (United States)

    Arai, Y.; Bugiel, Sz.; Dasgupta, R.; Idzik, M.; Kapusta, P.; Kucewicz, W.; Miyoshi, T.; Turala, M.

    2017-01-01

    Characterization of the monolithic pixel detector INPTIX6, designed at KEK and fabricated in Lapis 0.2 μ m Fully-Depleted, Low-Leakage Silicon-On-Insulator (SOI) CMOS technology, was performed. The INTPIX6 comprises a large area of 1408 × 896 integrating type squared pixels of 12 micron pitch. In this work the performance and measurement results of the prototypes produced on lower resistivity Czochralski type (CZ-n) and high resistivity floating zone (FZ-n) sensor wafers are presented. Using 241Am radioactive source the noise of INTPIX6 was measured, showing the ENC (Equivalent Noise Charge) of about 70 e-. The resolution calculated from the FWHM of the Iron-55 X-ray peak was about 100 e-. The radiation hardness of the SOI pixel detector was also investigated. The CZ-n type INTPIX6 received a dose of 60 krad and its performance has been continuously monitored during the irradiation.

  5. Studies of mono-crystalline CVD diamond pixel detectors

    CERN Document Server

    Bartz, E; Atramentov, O; Yang, Z; Hall-Wilton, R; Schnetzer, S; Patel, R; Bugg, W; Hebda, P; Halyo, V; Hunt, A; Marlow, D; Steininger, H; Ryjov, V; Hits, D; Spanier, S; Pernicka, M; Johns, W; Doroshenko, J; Hollingsworth, M; Harrop, B; Farrow, C; Stone, R

    2011-01-01

    The Pixel Luminosity Telescope (PLT) is a dedicated luminosity monitor, presently under construction, for the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). It measures the particle flux in several three layered pixel diamond detectors that are aligned precisely with respect to each other and the beam direction. At a lower rate it also performs particle track position measurements. The PLTs mono-crystalline CVD diamonds are bump-bonded to the same readout chip used in the silicon pixel system in CMS. Mono-crystalline diamond detectors have many attributes that make them desirable for use in charged particle tracking in radiation hostile environments such as the LHC. In order to further characterize the applicability of diamond technology to charged particle tracking we performed several tests with particle beams that included a measurement of the intrinsic spatial resolution with a high resolution beam telescope. Published by Elsevier B.V.

  6. Initial Measurements On Pixel Detector Modules For The ATLAS Upgrades

    CERN Document Server

    Gallrapp, C; The ATLAS collaboration

    2011-01-01

    Sophisticated conditions in terms of peak and integrated luminosity in the Large Hadron Collider (LHC) will raise the ATLAS Pixel detector to its performance limits. Silicon planar, silicon 3D and diamond pixel sensors are three possible sensor technologies which could be implemented in the upcoming pixel detector upgrades of the ATLAS experiment. Measurements of the IV-behavior and measurements with radioactive Americium-241 and Strontium-90 are used to characterize the sensor properties and to understand the interaction between the ATLAS FE-I4 front-end chip and the sensor. Comparisons of results from before and after irradiation, which give a first impression on the charge collection properties of the different sensor technologies are presented.

  7. The first bump-bonded pixel detectors on CVD diamond

    International Nuclear Information System (INIS)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Palmieri, V.G.; Pan, L.S.; Peitz, A.; Pernicka, M.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Steuerer, J.; Stone, R.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Turchetta, R.; Vittone, E.; Wagner, A.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Zeuner, W.; Ziock, H.; Zoeller, M.; Charles, E.; Ciocio, A.; Dao, K.; Einsweiler, K.; Fasching, D.; Gilchriese, M.; Joshi, A.; Kleinfelder, S.; Milgrome, O.; Palaio, N.; Richardson, J.; Sinervo, P.; Zizka, G.

    1999-01-01

    Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98% of the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 μm was observed, consistent with expectations given the detector pitch

  8. The first bump-bonded pixel detectors on CVD diamond

    CERN Document Server

    Adam, W; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Fried, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Palmieri, V G; Pan, L S; Peitz, A; Pernicka, Manfred; Pirollo, S; Polesello, P; Pretzl, Klaus P; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Steuerer, J; Stone, R; Tapper, R J; Tesarek, R J; Trawick, M L; Trischuk, W; Turchetta, R; Vittone, E; Wagner, A; Walsh, A M; Wedenig, R; Weilhammer, Peter; Zeuner, W; Ziock, H J; Zöller, M; Charles, E; Ciocio, A; Dao, K; Einsweiler, Kevin F; Fasching, D; Gilchriese, M G D; Joshi, A; Kleinfelder, S A; Milgrome, O; Palaio, N; Richardson, J; Sinervo, P K; Zizka, G

    1999-01-01

    Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98565544f the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 mu m was observed, consistent with expectations given the detector pitch. (13 refs).

  9. The first bump-bonded pixel detectors on CVD diamond

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Palmieri, V.G.; Pan, L.S.; Peitz, A.; Pernicka, M.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Steuerer, J.; Stone, R.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W. E-mail: william@physics.utoronto.ca; Turchetta, R.; Vittone, E.; Wagner, A.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Zeuner, W.; Ziock, H.; Zoeller, M.; Charles, E.; Ciocio, A.; Dao, K.; Einsweiler, K.; Fasching, D.; Gilchriese, M.; Joshi, A.; Kleinfelder, S.; Milgrome, O.; Palaio, N.; Richardson, J.; Sinervo, P.; Zizka, G

    1999-11-01

    Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98% of the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 {mu}m was observed, consistent with expectations given the detector pitch.

  10. Studies of mono-crystalline CVD diamond pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bugg, W. [University of Tennessee, Knoxville (United States); Hollingsworth, M., E-mail: mhollin3@utk.edu [University of Tennessee, Knoxville (United States); Spanier, S.; Yang, Z. [University of Tennessee, Knoxville (United States); Bartz, E.; Doroshenko, J.; Hits, D.; Schnetzer, S.; Stone, R.; Atramentov, O.; Patel, R.; Barker, A. [Rutgers University, Piscataway (United States); Hall-Wilton, R.; Ryjov, V.; Farrow, C. [CERN, Geneva (Switzerland); Pernicka, M.; Steininger, H. [HEPHY, Vienna (Austria); Johns, W. [Vanderbilt University, Nashville (United States); Halyo, V.; Harrop, B. [Princeton University, Princeton (United States); and others

    2011-09-11

    The Pixel Luminosity Telescope (PLT) is a dedicated luminosity monitor, presently under construction, for the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). It measures the particle flux in several three layered pixel diamond detectors that are aligned precisely with respect to each other and the beam direction. At a lower rate it also performs particle track position measurements. The PLT's mono-crystalline CVD diamonds are bump-bonded to the same readout chip used in the silicon pixel system in CMS. Mono-crystalline diamond detectors have many attributes that make them desirable for use in charged particle tracking in radiation hostile environments such as the LHC. In order to further characterize the applicability of diamond technology to charged particle tracking we performed several tests with particle beams that included a measurement of the intrinsic spatial resolution with a high resolution beam telescope.

  11. Spatial resolution of Medipix-2 device as neutron pixel detector

    Czech Academy of Sciences Publication Activity Database

    Jakůbek, J.; Holý, T.; Lehmann, E.; Pospíšil, S.; Uher, J.; Vacík, Jiří; Vavřík, D.

    2005-01-01

    Roč. 546, - (2005), s. 164-169 ISSN 0168-9002 R&D Projects: GA MŠk(CZ) 1P04LA211 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron detection * pixel detectors * neutronography Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.224, year: 2005

  12. Electron imaging with Medipix2 hybrid pixel detector

    CERN Document Server

    McMullan, G; Chen, S; Henderson, R; Llopart, X; Summerfield, C; Tlustos, L; Faruqi, A R

    2007-01-01

    The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 μm×55 μm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 μm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach 85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach 35% of that expected for a perfect detector (4/π2). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/π). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected v...

  13. Operational Experience and Performance with the ATLAS Pixel detector

    CERN Document Server

    Yang, Hongtao; The ATLAS collaboration

    2018-01-01

    In this presentation, I will discuss the operation of ATLAS Pixel Detector during Run 2 proton-proton data-taking at √s=13 TeV in 2017. The topics to be covered include 1) the bandwidth issue and how it is mitigated through readout upgrade and threshold adjustment; 2) the auto-corrective actions; 3) monitoring of radiation effects.

  14. Charge amplitude distribution of the Gossip gaseous pixel detector

    NARCIS (Netherlands)

    Blanco Carballo, V.M.; Chefdeville, M.A.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Gromov, V.; Hartjes, F.; Kluit, R.; Koffeman, E.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Timmermans, J.; Timmermans, J.; Visschers, J.L.

    2007-01-01

    The Gossip gaseous pixel detector is being developed for the detection of charged particles in extreme high radiation environments as foreseen close to the interaction point of the proposed super LHC. The detecting medium is a thin layer of gas. Because of the low density of this medium, only a few

  15. Planar sensors for the upgrade of the CMS pixel detector

    International Nuclear Information System (INIS)

    Rohe, T.; Bean, A.; Radicci, V.; Sibille, J.

    2011-01-01

    A replacement of the present CMS pixel detector with a better performing light weight four-layer system is foreseen in 2016. In the lifetime of this new system the LHC will reach and exceed its nominal luminosity of 10 34 cm -2 s -1 . Therefore the radiation hardness of all parts of the pixel system has to be reviewed. For the construction of the much larger four-layer pixel system, the replacement of the present double sided sensors by much cheaper single sided ones is considered. However, the construction of pixel modules with such sensors is challenging due to the small geometrical distance of the sensor high voltage and the ground of the readout electronics. This small distance limits the sensor bias to about 500 V in the tested samples.

  16. The effect of cathode bias (field effect) on the surface leakage current of CdZnTe detectors

    DEFF Research Database (Denmark)

    Bolotnikov, A.E.; Chen, C.M.H.; Cook, W.R.

    2003-01-01

    Surface resistivity is an important parameter of multi-electrode CZT detectors such as coplanar-grid, strip, or pixel detectors. Low surface resistivity results in a high leakage current and affects the charge collection efficiency in the areas near contacts. Thus, it is always desirable to have ...

  17. Development of a counting pixel detector for 'Digitales Roentgen'

    International Nuclear Information System (INIS)

    Lindner, M.

    2001-08-01

    The development of a single photon counting X-ray imaging detector for medical applications using hybrid pixel detectors is reported. The electronics development from the first prototype derived from detector development for particle physics experiments (ATLAS) to the imaging chip MPEC (multi picture element counters) for medical applications is described. This chip consists of 32 x 32 pixels of 200 μm x 200 μm size, each containing the complete read out electronics, i.e. an amplifier, two discriminators with adjustable thresholds and two 18-bit linear feedback shift-counters allowing energy windowing for contrast increase. Results on electronics performance are shown as well as measurements with several semiconductor materials (Si, GaAs, CdTe). Important aspects like detection efficiency, sensor homogeneity, linearity and spatial resolution are discussed. (orig.)

  18. An EUDET/AIDA Pixel Beam Telescope for Detector Development

    CERN Document Server

    Rubinskiy, I

    2015-01-01

    Ahigh resolution(σ< 2 μm) beam telescope based on monolithic active pixel sensors (MAPS) was developed within the EUDET collaboration. EUDET was a coordinated detector R&D programme for the future International Linear Collider providing test beam infrastructure to detector R&D groups. The telescope consists of six sensor planes with a pixel pitch of either 18.4 μm or 10 μmand canbe operated insidea solenoidal magnetic fieldofupto1.2T.Ageneral purpose cooling, positioning, data acquisition (DAQ) and offine data analysis tools are available for the users. The excellent resolution, readout rate andDAQintegration capabilities made the telescopea primary beam tests tool also for several CERN based experiments. In this report the performance of the final telescope is presented. The plans for an even more flexible telescope with three differentpixel technologies(ATLASPixel, Mimosa,Timepix) withinthenew European detector infrastructure project AIDA are presented.

  19. Optical Links for the ATLAS Pixel Detector

    CERN Document Server

    Gregor, Ingrid-Maria

    In der vorliegenden Dissertation wird eine strahlentolerante optische Datenstrecke mit hoher Datenrate für den Einsatz in dem Hochenergiephysikexperiment Atlas am Lhc Beschleuniger entwickelt. Da die Lhc-Experimente extremen Strahlenbelastungen ausgesetzt sind, müssen die Komponenten spezielle Ansprüche hinsichtlich der Strahlentoleranz erfüllen. Die Qualifikation der einzelnen Bauteile wurde im Rahmen dieser Arbeit durchgeführt. Die zu erwartenden Fluenzen im Atlas Inner Detector für Silizium und Gallium Arsenid (GaAs) wurden berechnet. Siliziumbauteile werden einer Fluenz von bis zu 1.1.1015neq /cm2 in 1 MeV äquivalenten Neutronen ausgesetzt sein, wohingegen GaAs Bauteile bis zu 7.8.1015neq /cm2 ausgesetzt sein werden. Die Strahlentoleranz der einzelnen benötigten Komponenten wie z.B. der Laserdioden sowie der jeweiligen Treiberchips wurde untersucht. Sowohl die Photo- als auch die Laserdioden haben sich als strahlentolerant für die Fluenzen an dem vorgesehenen Radius erwiesen. Aus de...

  20. Si and gaas pixel detectors for medical imaging applications

    International Nuclear Information System (INIS)

    Bisogni, M. G.

    2001-01-01

    As the use of digital radiographic equipment in the morphological imaging field is becoming the more and more diffuse, the research of new and more performing devices from public institutions and industrial companies is in constant progress. Most of these devices are based on solid-state detectors as X-ray sensors. Semiconductor pixel detectors, originally developed in the high energy physics environment, have been then proposed as digital detector for medical imaging applications. In this paper a digital single photon counting device, based on silicon and GaAs pixel detector, is presented. The detector is a thin slab of semiconductor crystal where an array of 64 by 64 square pixels, 170- m side, has been built on one side. The data read-out is performed by a VLSI integrated circuit named Photon Counting Chip (PCC), developed within the MEDIPIX collaboration. Each chip cell geometrically matches the sensor pixel. It contains a charge preamplifier, a threshold comparator and a 15 bits pseudo-random counter and it is coupled to the detector by means of bump bonding. Most important advantages of such system, with respect to a traditional X-rays film/screen device, are the wider linear dynamic range (3x104) and the higher performance in terms of MTF and DQE. Besides the single photon counting architecture allows to detect image contrasts lower than 3%. Electronics read-out performance as well as imaging capabilities of the digital device will be presented. Images of mammographic phantoms acquired with a standard Mammographic tube will be compared with radiographs obtained with traditional film/screen systems

  1. Characterisation of Redlen high-flux CdZnTe

    Science.gov (United States)

    Thomas, B.; Veale, M. C.; Wilson, M. D.; Seller, P.; Schneider, A.; Iniewski, K.

    2017-12-01

    CdZnTe is a promising material for the current generation of free electron laser light sources and future laser-driven γ-ray sources which require detectors capable of high flux imaging at X-ray and γ-ray energies (> 10 keV) . However, at high fluxes CdZnTe has been shown to polarise due to hole trapping, leading to poor performance. Novel Redlen CdZnTe material with improved hole transport properties has been designed for high flux applications. Small pixel CdZnTe detectors were fabricated by Redlen Technologies and flip-chip bonded to PIXIE ASICs. An XIA Digital Gamma Finder PIXIE-16 system was used to digitise each of the nine analogue signals with a timing resolution of 10 ns. Pulse shape analysis was used to extract the rise times and amplitude of signals. These were measured as a function of applied bias voltage and used to calculate the mobility (μ) and mobility-lifetime (μτ) of electrons and holes in the material for three identical detectors. The measured values of the transport properties of electrons in the high-flux-capable material was lower than previously reported for Redlen CdZnTe material (μeτe ~ 1 × 10-3 cm2V-1 and μe ~ 1000 cm2V-1s-1) while the hole transport properties were found to have improved (μhτh ~ 3 × 10-4 cm2V-1 and μh ~ 100 cm2V-1s-1).

  2. Test Beam Results of Geometry Optimized Hybrid Pixel Detectors

    CERN Document Server

    Becks, K H; Grah, C; Mättig, P; Rohe, T

    2006-01-01

    The Multi-Chip-Module-Deposited (MCM-D) technique has been used to build hybrid pixel detector assemblies. This paper summarises the results of an analysis of data obtained in a test beam campaign at CERN. Here, single chip hybrids made of ATLAS pixel prototype read-out electronics and special sensor tiles were used. They were prepared by the Fraunhofer Institut fuer Zuverlaessigkeit und Mikrointegration, IZM, Berlin, Germany. The sensors feature an optimized sensor geometry called equal sized bricked. This design enhances the spatial resolution for double hits in the long direction of the sensor cells.

  3. Radiation damage monitoring in the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Seidel, Sally

    2013-01-01

    We describe the implementation of radiation damage monitoring using measurement of leakage current in the ATLAS silicon pixel sensors. The dependence of the leakage current upon the integrated luminosity is presented. The measurement of the radiation damage corresponding to an integrated luminosity 5.6 fb −1 is presented along with a comparison to a model. -- Highlights: ► Radiation damage monitoring via silicon leakage current is implemented in the ATLAS (LHC) pixel detector. ► Leakage currents measured are consistent with the Hamburg/Dortmund model. ► This information can be used to validate the ATLAS simulation model.

  4. Semiconductor micropattern pixel detectors a review of the beginnings

    CERN Document Server

    Heijne, Erik H M

    2001-01-01

    The innovation in monolithic and hybrid semiconductor 'micropattern' or 'reactive' pixel detectors for tracking in particle physics was actually to fit logic and pulse processing electronics with µW power on a pixel area of less than 0.04 mm2, retaining the characteristics of a traditional nuclear amplifier chain. The ns timing precision in conjunction with local memory and logic operations allowed event selection at > 10 MHz rates with unambiguous track reconstruction even at particle multiplicities > 10 cm-2. The noise in a channel was ~100 e- r.m.s. and enabled binary operation with random noise 'hits' at a level 30 Mrad, respectively.

  5. Silicon sensors for the upgrades of the CMS pixel detector

    International Nuclear Information System (INIS)

    Centis Vignali, Matteo

    2015-12-01

    The Compact Muon Solenoid (CMS) is a general purpose detector at the Large Hadron Collider (LHC). The LHC luminosity is constantly increased through upgrades of the accelerator and its injection chain. Two major upgrades will take place in the next years. The first upgrade involves the LHC injector chain and allows the collider to achieve a luminosity of about 2.10 34 cm -2 s -1 . A further upgrade of the LHC foreseen for 2025 will boost its luminosity to 5.10 34 cm -2 s -1 . As a consequence of the increased luminosity, the detectors need to be upgraded. In particular, the CMS pixel detector will undergo two upgrades in the next years. The first upgrade (phase I) consists in the substitution of the current pixel detector in winter 2016/2017. The upgraded pixel detector will implement new readout electronics that allow efficient data taking up to a luminosity of 2.10 34 cm -2 s -1 , twice as much as the LHC design luminosity. The modules that will constitute the upgraded detector are being produced at different institutes. Hamburg (University and DESY) is responsible for the production of 350 pixel modules. The second upgrade (phase II) of the pixel detector is foreseen for 2025. The innermost pixel layer of the upgraded detector will accumulate a radiation damage corresponding to an equivalent fluence of Φ eq =2.10 16 cm -2 and a dose of ∼10 MGy after an integrated luminosity of 3000 fb -1 . Several groups are investigating sensor designs and configurations able to withstand such high doses and fluences. This work is divided into two parts related to important aspects of the upgrades of the CMS pixel detector. For the phase I upgrade, a setup has been developed to provide an absolute energy calibration of the pixel modules that will constitute the detector. The calibration is obtained using monochromatic X-rays. The same setup is used to test the buffering capabilities of the modules' readout chip. The maximum rate experienced by the modules produced in

  6. CdZnTe and CdTe materials for X-ray and gamma ray radiation detector applications

    International Nuclear Information System (INIS)

    Szeles, Csaba

    2004-01-01

    Good detection efficiency and high energy-resolution make Cadmium Zinc Telluride (CdZnTe) and Cadmium Telluride (CdTe) detectors attractive in many room temperature X-ray and gamma-ray detection applications such as medical and industrial imaging, industrial gauging and non-destructive testing, security and monitoring, nuclear safeguards and non-proliferation, and astrophysics. Advancement of the crystal growth and device fabrication technologies and the reduction of bulk, interface and surface defects in the devices are crucial for the widespread practical deployment of Cd 1-x Zn x Te-based detector technology. Here we review the effects of bulk, interface and surface defects on charge transport, charge transport uniformity and device performance and the progress in the crystal growth and device fabrication technologies aiming at reducing the concentration of harmful defects and improving Cd 1-x Zn x Te detector performance. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Rossini, Lorenzo; The ATLAS collaboration

    2018-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of 10^15 neq/cm^2 and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current and future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time and considers both planar and 3D sensor designs. In addition to thoroughly describing the setup, we compare predictions for b...

  8. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Rossini, Lorenzo; The ATLAS collaboration

    2018-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High- Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time and considers both planar and 3D sensor designs. In addition to thoroughly describing the setup, we compare predictions for basic...

  9. The ALICE Silicon Pixel Detector Control and Calibration Systems

    CERN Document Server

    Calì, Ivan Amos; Manzari, Vito; Stefanini, Giorgio

    2008-01-01

    The work presented in this thesis was carried out in the Silicon Pixel Detector (SPD) group of the ALICE experiment at the Large Hadron Collider (LHC). The SPD is the innermost part (two cylindrical layers of silicon pixel detec- tors) of the ALICE Inner Tracking System (ITS). During the last three years I have been strongly involved in the SPD hardware and software development, construction and commissioning. This thesis is focused on the design, development and commissioning of the SPD Control and Calibration Systems. I started this project from scratch. After a prototyping phase now a stable version of the control and calibration systems is operative. These systems allowed the detector sectors and half-barrels test, integration and commissioning as well as the SPD commissioning in the experiment. The integration of the systems with the ALICE Experiment Control System (ECS), DAQ and Trigger system has been accomplished and the SPD participated in the experimental December 2007 commissioning run. The complex...

  10. Monolithic active pixel radiation detector with shielding techniques

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz W.

    2018-03-20

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  11. Design studies on sensors for the ATLAS Pixel Detector

    CERN Document Server

    Hügging, F G

    2002-01-01

    For the ATLAS Pixel Detector, prototype sensors have been successfully developed. For the sensors design, attention was given to survivability of the harsh LHC radiation environment leading to the need to operate them at several hundreds of volts, while maintaining a good charge collection efficiency, small cell size and minimal multiple scattering. For a cost effective mass production, a bias grid is implemented to test the sensors before assembly under full bias. (6 refs).

  12. Studies on MCM-D pixel-detector-modules

    CERN Document Server

    Flick, T; Gerlach, P; Grah, C; Mättig, P; Rohe, T

    2003-01-01

    In the context of the development of the ATLAS-pixel-detector, a technology for building up the high density interconnects has been studied, the MCM-D (multichip module deposited) technology. Results of building up first assemblies have been reported. MCM-D technology allows to build up assemblies with uniformly segmented sensors. Especially the use of 'equal-sized(-bricked)' sensor geometry has been studied.

  13. Hexagonal pixel detector with time encoded binary readout

    International Nuclear Information System (INIS)

    Hoedlmoser, H.; Varner, G.; Cooney, M.

    2009-01-01

    The University of Hawaii is developing continuous acquisition pixel (CAP) detectors for vertexing applications in lepton colliding experiments such as SuperBelle or ILC. In parallel to the investigation of different technology options such as MAPS or SOI, both analog and binary readout concepts have been tested. First results with a binary readout scheme in which the hit information is time encoded by means of a signal shifting mechanism have recently been published. This paper explains the hit reconstruction for such a binary detector with an emphasis on fake hit reconstruction probabilities in order to evaluate the rate capability in a high background environment such as the planned SuperB factory at KEK. The results show that the binary concept is at least comparable to any analog readout strategy if not better in terms of occupancy. Furthermore, we present a completely new binary readout strategy in which the pixel cells are arranged in a hexagonal grid allowing the use of three independent output directions to reduce reconstruction ambiguities. The new concept uses the same signal shifting mechanism for time encoding, however, in dedicated transfer lines on the periphery of the detector, which enables higher shifting frequencies. Detailed Monte Carlo simulations of full size pixel matrices including hit and BG generation, signal generation, and data reconstruction show that by means of multiple signal transfer lines on the periphery the pixel can be made smaller (higher resolution), the number of output channels and the data volume per triggered event can be reduced dramatically, fake hit reconstruction is lowered to a minimum and the resulting effective occupancies are less than 10 -4 . A prototype detector has been designed in the AMS 0.35μm Opto process and is currently under fabrication.

  14. A DAQ system for pixel detectors R and D

    International Nuclear Information System (INIS)

    Battaglia, M.; Bisello, D.; Contarato, D.; Giubilato, P.; Pantano, D.; Tessaro, M.

    2009-01-01

    Pixel detector R and D for HEP and imaging applications require an easily configurable and highly versatile DAQ system able to drive and read out many different chip designs in a transparent way, with different control logics and/or clock signals. An integrated, real-time data collection and analysis environment is essential to achieve fast and reliable detector characterization. We present a DAQ system developed to fulfill these specific needs, able to handle multiple devices at the same time while providing a convenient, ROOT based data display and online analysis environment.

  15. NEW LENSLET BASED IFS WITH HIGH DETECTOR PIXEL EFFICIENCY

    Science.gov (United States)

    Gong, Qian

    2018-01-01

    Three IFS types currently used for optical design are: lenslet array, imager slicer, and lenslet array and fiber combined. Lenslet array based Integral Field Spectroscopy (IFS) is very popular for many astrophysics applications due to its compactness, simplicity, as well as cost and mass savings. The disadvantage of lenslet based IFS is its low detector pixel efficiency. Enough spacing is needed between adjacent spectral traces in cross dispersion direction to avoid wavelength cross-talk, because the same wavelength is not aligned to the same column on detector. Such as on a recent exoplanet coronagraph instrument study to support the coming astrophysics decadal survey (LUVOIR), to cover a 45 λ/D Field of View (FOV) with a spectral resolving power of 200 at shortest wavelength, a 4k x 4k detector array is needed. This large format EMCCD pushes the detector into technology development area with a low TRL. Besides the future mission, it will help WFIRST coronagraph IFS by packing all spectra into a smaller area on detector, which will reduce the chance for electrons to be trapped in pixels, and slow the detector degradation during the mission.The innovation we propose here is to increase the detector packing efficiency by grouping a number of lenslets together to form many mini slits. In other words, a number of spots (Point Spread Function at lenslet focus) are aligned into a line to resemble a mini slit. Therefore, wavelength cross-talk is no longer a concern anymore. This combines the advantage of lenslet array and imager slicer together. The isolation rows between spectral traces in cross dispersion direction can be reduced or removed. So the packing efficiency is greatly increased. Furthermore, the today’s microlithography and etching technique is capable of making such a lenslet array, which will relax the detector demand significantly. It will finally contribute to the habitable exoplanets study to analyzing their spectra from direct images. Detailed theory

  16. Studies on a 300 k pixel detector telescope

    Science.gov (United States)

    Middelkamp, Peter; Antinori, F.; Barberis, D.; Becks, K. H.; Beker, H.; Beusch, W.; Burger, P.; Campbell, M.; Cantatore, E.; Catanesi, M. G.; Chesi, E.; Darbo, G.; D'Auria, S.; Davia, C.; di Bari, D.; di Liberto, S.; Elia, D.; Gys, T.; Heijne, E. H. M.; Helstrup, H.; Jacholkowski, A.; Jæger, J. J.; Jakubek, J.; Jarron, P.; Klempt, W.; Krummenacher, F.; Knudson, K.; Kralik, I.; Kubasta, J.; Lasalle, J. C.; Leitner, R.; Lemeilleur, F.; Lenti, V.; Letheren, M.; Lopez, L.; Loukas, D.; Luptak, M.; Martinengo, P.; Meddeler, G.; Meddi, F.; Morando, M.; Munns, A.; Pellegrini, F.; Pengg, F.; Pospisil, S.; Quercigh, E.; Ridky, J.; Rossi, L.; Safarik, K.; Scharfetter, L.; Segato, G.; Simone, S.; Smith, K.; Snoeys, W.; Vrba, V.

    1996-02-01

    Four silicon pixel detector planes are combined to form a tracking telescope in the lead ion experiment WA97 at CERN with 290 304 sensitive elements each of 75 μm by 500 μm area. An electronic pulse processing circuit is associated with each individual sensing element and the response for ionizing particles is binary with an adjustable threshold. The noise rate for a threshold of 6000 e- has been measured to be less than 10-10. The inefficient area due to malfunctioning pixels is 2.8% of the 120 cm2. Detector overlaps within one plane have been used to determine the alignment of the components of the plane itself, without need for track reconstruction using external detectors. It is the first time that such a big surface covered with active pixels has been used in a physics experiment. Some aspects concerning inclined particle tracks and time walk have been measured separately in a beam test at the CERN SPS H6 beam.

  17. Studies on a 300 k pixel detector telescope

    International Nuclear Information System (INIS)

    Middelkamp, P.; Antinori, F.; Barberis, D.

    1996-01-01

    Four silicon pixel detector planes are combined to form a tracking telescope in the lead ion experiment WA97 at CERN with 290 304 sensitive elements each of 75 μm by 500 μm area. An electronic pulse processing circuit is associated with each individual sensing element and the response for ionizing particles is binary with an adjustable threshold. The noise rate for a threshold of 6000 e - has been measured to be less than 10 -10 . The inefficient area due to malfunctioning pixels is 2.8% of the 120 cm 2 . Detector overlaps within one plane have been used to determine the alignment of the components of the plane itself, without need for track reconstruction using external detectors. It is the first time that such a big surface covered with active pixels has been used in a physics experiment. Some aspects concerning inclined particle tracks and time walk have been measured separately in a beam test at the CERN SPS H6 beam. (orig.)

  18. Point Defect Properties of Cd(Zn)Te and TlBr for Room-Temperature Gamma Radiation Detectors

    Science.gov (United States)

    Lordi, Vincenzo

    2013-03-01

    The effects of various crystal defects in CdTe, Cd1-xZnxTe (CZT), and TlBr are critical for their performance as room-temperature gamma radiation detectors. We use predictive first principles theoretical methods to provide fundamental, atomic scale understanding of the defect properties of these materials to enable design of optimal growth and processing conditions, such as doping, annealing, and stoichiometry. Several recent cases will be reviewed, including (i) accurate calculations of the thermodynamic and electronic properties of native point defects and point defect complexes in CdTe and CZT; (ii) the effects of Zn alloying on the native point defect properties of CZT; (iii) point defect diffusion and binding related to Te clustering in Cd(Zn)Te; (iv) the profound effect of native point defects--principally vacancies--on the intrinsic material properties of TlBr, particularly electronic and ionic conductivity; (v) tailored doping of TlBr to independently control the electronic and ionic conductivity; and (vi) the effects of metal impurities on the electronic properties and device performance of TlBr detectors. Prepared by LLNL under Contract DE-AC52-07NA27344 with support from the National Nuclear Security Administration Office of Nonproliferation and Verification Research and Development NA-22.

  19. The CdZnTe Detector with Slit Collimator for Measure Distribution of the Specific Activity Radionuclide in the Ground

    Science.gov (United States)

    Stepanov, V. E.; Volkovich, A. G.; Potapov, V. N.; Semin, I. A.; Stepanov, A. V.; Simirskii, Iu. N.

    2018-01-01

    From 2011 in the NRC "Kurchatov Institute" carry out the dismantling of the MR multiloop research reactor. Now the reactor and all technological equipment in the premises of the reactor were dismantled. Now the measurements of radioactive contamination in the reactor premises are made. The most contaminated parts of premises - floor and the ground beneath it. To measure the distribution of specific activity in the ground the CdZnTe detector (volume 500MM3) was used. Detector placed in a lead shielding with a slit collimation hole. The upper part of shielding is made movable to close and open the slit of the collimator. At each point two measurements carried out: with open and closed collimator. The software for determination specific activity of radionuclides in ground was developed. The mathematical model of spectrometric system based on the Monte-Carlo method. Measurements of specific activity of ground were made. Using the results of measurements the thickness of the removed layer of ground and the amount of radioactive waste were calculated.

  20. The effect of cathode bias (field effect) on the surface leakage current of CdZnTe detectors

    International Nuclear Information System (INIS)

    Bolotnikov, A.E.; Hubert Chen, C.M.; Cook, W.R.; Harrison, F.A.; Kuvvetli, I.; Schindler, S.M.; Stahle, C.M.; Parker, B.H.

    2003-01-01

    Surface resistivity is an important parameter of multi-electrode CZT detectors such as coplanar-grid, strip, or pixel detectors. Low surface resistivity results in a high leakage current and affects the charge collection efficiency in the areas near contacts. Thus, it is always desirable to have the surface resistivity of the detector as high as possible. In the past the most significant efforts were concentrated to develop passivation techniques for CZT detectors. However, as we found, the field-effect caused by a bias applied on the cathode can significantly reduce the surface resistivity even though the detector surface was carefully passivated. In this paper we illustrate that the field-effect is a common feature of the CZT multi-electrode detectors, and discuss how to take advantage of this effect to improve the surface resistivity of CZT detectors

  1. Detection of secondary electrons with pixelated hybrid semiconductor detectors

    International Nuclear Information System (INIS)

    Gebert, Ulrike Sonja

    2011-01-01

    Within the scope of this thesis, secondary electrons were detected with a pixelated semiconductor detector named Timepix. The Timepix detector consists of electronics and a sensor made from a semiconductor material. The connection of sensor and electronics is done for each pixel individually using bump bonds. Electrons with energies above 3 keV can be detected with the sensor. One electron produces a certain amount of electron-hole pairs according to its energy. The charge then drifts along an electric field to the pixel electronics, where it induces an electric signal. Even without a sensor it is possible to detect an electric signal from approximately 1000 electrons directly in the pixel electronics. Two different detector systems to detect secondary electrons using the Timepix detector were investigated during this thesis. First of all, a hybrid photon detector (HPD) was used to detect single photoelectrons. The HPD consists of a vacuum vessel with an entrance window and a cesium iodine photocathode at the inner surface of the window. Photoelectrons are released from the photocathode by incident light and are accelerated in an electric field towards the Timepix detector, where the point of interaction and the arrival time of the electron is determined. With a proximity focusing setup, a time resolution of 12 ns (with an acceleration voltage of 20 kV between photocathode and Timepix detector) was obtained. The HPD examined in this thesis showed a strong dependence of the dark rate form the acceleration voltage and the pressure in the vacuum vessel. At a pressure of few 10 -5 mbar and an acceleration voltage of 20 kV, the dark rate was about 800 Hz per mm 2 area of the read out photocathode. One possibility to reduce the dark rate is to identify ion feedback events. With a slightly modified setup it was possible to reduce the dark rate to 0.5 Hz/mm 2 . To achieve this, a new photocathode was mounted in a shorter distance to the detector. The measurements where

  2. Study of CdTe:Cl and CdZnTe detectors for medical multi-slices X-ray Computed Tomography

    International Nuclear Information System (INIS)

    Ricq, St.

    1999-01-01

    The application of CdTe and CdZnTe detectors to medical X-ray Computed Tomography have been investigated. Different electrodes (Au, Pt, In) have been deposited on CdZnTe HPBM and on CdTe:ClTHM. Their injection properties have been determined with Current-Voltage characteristics. Under X-ray in CT conditions, injection currents measurements reveal trapped carriers space-charges formation. The same way, the comparisons of the responses to X-beam cut-off with various injection possibilities enable to follow the space-charges evolutions and then to determine the predominant traps types. Nevertheless, both hole and electron traps are responsible for the memory effect e.g. the currents levels dependence with irradiation history. This effect is noticed in particular on responses to fast flux variations that simulate scanner's conditions. Trap levels probably corresponding to native defects are responsible for these limitations. In order to make such detectors suitable for X-ray Computed Tomography, significant progresses in CdTe for CdZnTe crystal growth with an important defects densities reduction (factor 10), or possibly counting mode operation, seem necessary. (author)

  3. The data acquisition system of the Belle II Pixel Detector

    Science.gov (United States)

    Münchow, D.; Dingfelder, J.; Geßler, T.; Konorov, I.; Kühn, W.; Lange, S.; Lautenbach, K.; Levit, D.; Liu, Z.; Marinas, C.; Schnell, M.; Spruck, B.; Zhao, J.

    2014-08-01

    At the future Belle II experiment the DEPFET (DEPleted Field Effect Transistor) pixel detector will consist of about 8 million channels and is placed as the innermost detector. Because of its small distance to the interaction region and the high luminosity in Belle II, for a trigger rate of about 30 kHz with an estimated occupancy of about 3 % a data rate of about 22 GB/s is expected. Due to the high data rate, a data reduction factor higher than 30 is needed in order to stay inside the specifications of the event builder. The main hardware to reduce the data rate is a xTCA based Compute Node (CN) developed in cooperation between IHEP Beijing and University Giessen. Each node has as main component a Xilinx Virtex-5 FX70T FPGA and is equipped with 2 × 2 GB RAM , GBit Ethernet and 4 × 6.25 Gb/s optical links. An ATCA carrier board is able to hold up to four CN and supplies high bandwidth connections between the four CNs and to the ATCA backplane. To achieve the required data reduction on the CNs, regions of interest (ROI) are used. These regions are calculated in two independent systems by projecting tracks back to the pixel detector. One is the High Level Trigger (HLT) which uses data from the Silicon Vertex Detector (SVD), a silicon strip detector, and outer detectors. The other is the Data Concentrator (DATCON) which calculates ROIs based on SVD data only, in order to get low momentum tracks. With this information, only PXD data inside these ROIs will be forwarded to the event builder, while data outside of these regions will be discarded. First results of the test beam time in January 2014 at DESY with a Belle II vertex detector prototype and full DAQ chain will be presented.

  4. Neutron irradiation test of depleted CMOS pixel detector prototypes

    International Nuclear Information System (INIS)

    Mandić, I.; Cindro, V.; Gorišek, A.; Hiti, B.; Kramberger, G.; Mikuž, M.; Zavrtanik, M.; Hemperek, T.; Daas, M.; Hügging, F.; Krüger, H.; Pohl, D.-L.; Wermes, N.; Gonella, L.

    2017-01-01

    Charge collection properties of depleted CMOS pixel detector prototypes produced on p-type substrate of 2 kΩ cm initial resistivity (by LFoundry 150 nm process) were studied using Edge-TCT method before and after neutron irradiation. The test structures were produced for investigation of CMOS technology in tracking detectors for experiments at HL-LHC upgrade. Measurements were made with passive detector structures in which current pulses induced on charge collecting electrodes could be directly observed. Thickness of depleted layer was estimated and studied as function of neutron irradiation fluence. An increase of depletion thickness was observed after first two irradiation steps to 1 · 10 13 n/cm 2 and 5 · 10 13 n/cm 2 and attributed to initial acceptor removal. At higher fluences the depletion thickness at given voltage decreases with increasing fluence because of radiation induced defects contributing to the effective space charge concentration. The behaviour is consistent with that of high resistivity silicon used for standard particle detectors. The measured thickness of the depleted layer after irradiation with 1 · 10 15 n/cm 2 is more than 50 μm at 100 V bias. This is sufficient to guarantee satisfactory signal/noise performance on outer layers of pixel trackers in HL-LHC experiments.

  5. Noise propagation issues in Belle II pixel detector power cable

    Science.gov (United States)

    Iglesias, M.; Arteche, F.; Echeverria, I.; Pradas, A.; Rivetta, C.; Moser, H.-G.; Kiesling, C.; Rummel, S.; Arcega, F. J.

    2018-04-01

    The vertex detector used in the upgrade of High-Energy physics experiment Belle II includes DEPFET pixel detector (PXD) technology. In this complex topology the power supply units and the front-end electronics are connected through a PXD power cable bundle which may propagate the output noise from the power supplies to the vertex area. This paper presents a study of the propagation of noise caused by power converters in the PXD cable bundle based on Multi-conductor Transmission Line (MTL) theory. The work exposes the effect of the complex cable topology and shield connections on the noise propagation, which has an impact on the requirements of the power supplies. This analysis is part of the electromagnetic compatibility based design focused on functional safety to define the shield connections and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.

  6. Advanced processing of CdTe pixel radiation detectors

    Science.gov (United States)

    Gädda, A.; Winkler, A.; Ott, J.; Härkönen, J.; Karadzhinova-Ferrer, A.; Koponen, P.; Luukka, P.; Tikkanen, J.; Vähänen, S.

    2017-12-01

    We report a fabrication process of pixel detectors made of bulk cadmium telluride (CdTe) crystals. Prior to processing, the quality and defect density in CdTe material was characterized by infrared (IR) spectroscopy. The semiconductor detector and Flip-Chip (FC) interconnection processing was carried out in the clean room premises of Micronova Nanofabrication Centre in Espoo, Finland. The chip scale processes consist of the aluminum oxide (Al2O3) low temperature thermal Atomic Layer Deposition (ALD), titanium tungsten (TiW) metal sputtering depositions and an electroless Nickel growth. CdTe crystals with the size of 10×10×0.5 mm3 were patterned with several photo-lithography techniques. In this study, gold (Au) was chosen as the material for the wettable Under Bump Metalization (UBM) pads. Indium (In) based solder bumps were grown on PSI46dig read out chips (ROC) having 4160 pixels within an area of 1 cm2. CdTe sensor and ROC were hybridized using a low temperature flip-chip (FC) interconnection technique. The In-Au cold weld bonding connections were successfully connecting both elements. After the processing the detector packages were wire bonded into associated read out electronics. The pixel detectors were tested at the premises of Finnish Radiation Safety Authority (STUK). During the measurement campaign, the modules were tested by exposure to a 137Cs source of 1.5 TBq for 8 minutes. We detected at the room temperature a photopeak at 662 keV with about 2 % energy resolution.

  7. Performance of the INTPIX6 SOI pixel detector

    International Nuclear Information System (INIS)

    Arai, Y.; Miyoshi, T.; Bugiel, Sz.; Dasgupta, R.; Idzik, M.; Kapusta, P.; Turala, M.; Kucewicz, W.

    2017-01-01

    Characterization of the monolithic pixel detector INPTIX6, designed at KEK and fabricated in Lapis 0.2 μ  m Fully-Depleted, Low-Leakage Silicon-On-Insulator (SOI) CMOS technology, was performed. The INTPIX6 comprises a large area of 1408 × 896 integrating type squared pixels of 12 micron pitch. In this work the performance and measurement results of the prototypes produced on lower resistivity Czochralski type (CZ-n) and high resistivity floating zone (FZ-n) sensor wafers are presented. Using 241 Am radioactive source the noise of INTPIX6 was measured, showing the ENC (Equivalent Noise Charge) of about 70 e − . The resolution calculated from the FWHM of the Iron-55 X-ray peak was about 100 e − . The radiation hardness of the SOI pixel detector was also investigated. The CZ-n type INTPIX6 received a dose of 60 krad and its performance has been continuously monitored during the irradiation.

  8. Design and Measurement of a Low-Noise 64-Channels Front-End Readout ASIC for CdZnTe Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Bo; Wei, Tingcun; Gao, Wu; Liu, Hui; Hu, Yann [School of Computer Science and Technology, Northwestern Polytechnical University, Xi' an (China)

    2015-07-01

    Cadmium zinc telluride (CdZnTe) detectors, as one of the principal detectors for the next-generation X-ray and γ-ray imagers, have high energy resolution and supporting electrode patterning in the radiation environment at room-temperature. In the present, a number of internationally renowned research institutions and universities are actively using these detector systems to carry out researches of energy spectrum analysis, medical imaging, materials characterization, high-energy physics, nuclear plant monitoring, and astrophysics. As the most important part of the readout system for the CdZnTe detector, the front-end readout application specific integrated circuit (ASIC) would have an important impact on the performances of the whole detector system. In order to ensure the small signal to noise ratio (SNR) and sufficient range of the output signal, it is necessary to design a front-end readout ASIC with very low noise and very high dynamic range. In addition, radiation hardness should be considered when the detectors are utilized in the space applications and high energy physics experiments. In this paper, we present measurements and performances of a novel multi-channel radiation-hardness low-noise front-end readout ASIC for CdZnTe detectors. The readout circuits in each channel consist of charge sensitive amplifier, leakage current compensation circuit (LCC), CR-RC shaper, S-K filter, inverse proportional amplifier, peak detect and hold circuit (PDH), discriminator and trigger logic, time sequence control circuit and driving buffer. All of 64 readout channels' outputs enter corresponding inputs of a 64 channel multiplexer. The output of the mux goes directly out of the chip via the output buffer. The 64-channel readout ASIC is implemented using the TSMC 0.35 μm mixed-signal CMOS technology. The die size of the prototype chip is 2.7 mm x 8 mm. At room temperature, the equivalent noise level of a typical channel reaches 66 e{sup -} (rms) at zero farad for a

  9. An EUDET/AIDA Pixel Beam Telescope for Detector Development

    CERN Document Server

    Perrey, Hanno

    2013-01-01

    A high resolution ($\\sigma 2 \\sim \\mu$) beam telescope based on monolithic active pixel sensors (MAPS) was developed within the EUDET collaboration. The telescope consists of six sensor planes using Mimosa26 MAPS with a pixel pitch of $18.4 \\mu$ and thinned down to $50 \\mu$. The excellent resolution, readout rate and DAQ integration capabilities made the telescope a primary test beam tool for many groups including several CERN based experiments. Within the new European detector infrastructure project AIDA the test beam telescope will be further extended in terms of cooling infrastructure, readout speed and precision. In order to provide a system optimized for the different requirements by the user community, a combination of various pixel technologies is foreseen. In this report the design of this even more flexible telescope with three different pixel technologies (TimePix, Mimosa, ATLAS FE-I4) will be presented. First test beam results with the HitOR signal provided by the FE-I4 integrated into the trigger...

  10. Semiconductor micropattern pixel detectors: a review of the beginnings

    International Nuclear Information System (INIS)

    Heijne, E.H.M.

    2001-01-01

    The innovation in monolithic and hybrid semiconductor 'micropattern' or 'reactive' pixel detectors for tracking in particle physics was actually to fit logic and pulse processing electronics with μW power on a pixel area of less than 0.04 mm 2 , retaining the characteristics of a traditional nuclear amplifier chain. The ns timing precision in conjunction with local memory and logic operations allowed event selection at >10 MHz rates with unambiguous track reconstruction even at particle multiplicities >10 cm -2 . The noise in a channel was ∼100e - rms and enabled binary operation with random noise 'hits' at a level -8 . Rectangular pixels from 75 μmx500 μm down to 34 μmx125 μm have been used by different teams. In binary mode a tracking precision from 6 to 14 μm was obtained, and using analog interpolation one came close to 1 μm. Earlier work, still based on charge integrating imaging circuits, provided a starting point. Two systems each with more than 1 million sensor + readout channels have been built, for WA97-NA57 and for the Delphi very forward tracker. The use of 0.5 μm and 0.25 μm CMOS and enclosed geometry for the transistors in the pixel readout chips resulted in radiation hardness of ∼2 Mrad, respectively, >30 Mrad

  11. Charge Gain, Voltage Gain, and Node Capacitance of the SAPHIRA Detector Pixel by Pixel

    Science.gov (United States)

    Pastrana, Izabella M.; Hall, Donald N. B.; Baker, Ian M.; Jacobson, Shane M.; Goebel, Sean B.

    2018-01-01

    The University of Hawai`i Institute for Astronomy has partnered with Leonardo (formerly Selex) in the development of HgCdTe linear mode avalanche photodiode (L-APD) SAPHIRA detectors. The SAPHIRA (Selex Avalanche Photodiode High-speed Infra-Red Array) is ideally suited for photon-starved astronomical observations, particularly near infrared (NIR) adaptive optics (AO) wave-front sensing. I have measured the stability, and linearity with current, of a 1.7-um (10% spectral bandpass) infrared light emitting diode (IR LED) used to illuminate the SAPHIRA and have then utilized this source to determine the charge gain (in e-/ADU), voltage gain (in uV/ADU), and node capacitance (in fF) for each pixel of the 320x256@24um SAPHIRA. These have previously only been averages over some sub-array. Determined from the ratio of the temporal averaged signal level to variance under constant 1.7-um LED illumination, I present the charge gain pixel-by-pixel in a 64x64 sub-array at the center of the active area of the SAPHIRA (analyzed separately as four 32x32 sub-arrays) to be about 1.6 e-/ADU (σ=0.5 e-/ADU). Additionally, the standard technique of varying the pixel reset voltage (PRV) in 10 mV increments and recording output frames for the same 64x64 subarray found the voltage gain per pixel to be about 11.7 uV/ADU (σ=0.2 uV/ADU). Finally, node capacitance was found to be approximately 23 fF (σ=6 fF) utilizing the aforementioned charge and voltage gain measurements. I further discuss the linearity measurements of the 1.7-um LED used in the charge gain characterization procedure.

  12. International Workshop on Semiconductor Pixel Detectors for Particles and Imaging (PIXEL2016)

    CERN Document Server

    Rossi, Leonardo; PIXEL2016

    2016-01-01

    The workshop will cover various topics related to pixel detector technology. Development and applications will be discussed for charged particle tracking in High Energy Physics, Nuclear Physics and Astrophysics, and for X-ray imaging in Astronomy, Biology, Medicine and Material Science. The conference program will also include reports on front and back end electronics, radiation effects, low mass mechanics, environmental control and construction techniques. Emerging technologies, such as monolithic and HV&HR CMOS, will also be treated. Will be published in: http://pos.sissa.it/

  13. On the basic mechanism of Pixelized Photon Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Otono, H. [Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)], E-mail: otono@icepp.s.u-tokyo.ac.jp; Oide, H. [Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yamashita, S. [International Center for Elementary Particle Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Yoshioka, T. [Neutron Science Laboratory, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2009-10-21

    A Pixelized Photon Detector (PPD) is a generic name for the semiconductor devices operated in the Geiger-mode, such as Silicon PhotoMultiplier and Multi-Pixel Photon Counter, which has high photon counting capability. While the internal mechanisms of the PPD have been intensively studied in recent years, the existing models do not include the avalanche process. We have simulated the multiplication and quenching of the avalanche process and have succeeded in reproducing the output waveform of the PPD. Furthermore our model predicts the existence of dead-time in the PPD which has never been numerically predicted. For searching the dead-time, we also have developed waveform analysis method using deconvolution which has the potential to distinguish neighboring pulses precisely. In this paper, we discuss our improved model and waveform analysis method.

  14. Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

    CERN Document Server

    AUTHOR|(SzGeCERN)734627; Benoit, Mathieu; Dannheim, Dominik; Dette, Karola; Hynds, Daniel; Kulis, Szymon; Peric, Ivan; Petric, Marko; Redford, Sophie; Sicking, Eva; Valerio, Pierpaolo

    2016-01-01

    The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor. Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

  15. Theoretical evaluation of the Doppler broadening contribution to the angular resolution in CdZnTe Compton scattering detector

    International Nuclear Information System (INIS)

    Diaz Garcia, A.; Cabal Rodriguez, A.E.; Rubio Rodriguez, J. A.; Salicio Diez, J.; Perez Morales, J.M.; Vela Morales, O.; Willmott Zappacosta, C.; Van Espen, P.

    2011-01-01

    Electronically collimated Compton Cameras have been tested in Single Photon Emission Tomography (SPECT) systems instead of mechanically collimated gamma detectors in order to improve their limited sensitivity. One of the main factors that contribute to the worsening of the angular resolution and thus to the deterioration of the system spatial resolution is Doppler broadening. Double differential Klein-Nishina equation is used to consider the random movement of electron inside the crystal. It is important to perform this analysis for each particular material because is difficult to infer one simple Doppler broadening dependency of the atomic number Z. In high Z materials the internal electrons are strongly linked to the nucleus and therefore there can be found high momentums, but they represent just a small portion of the electrons that suffers Compton scattering. This work estimates the influence of the Doppler broadening in CdZnTe semiconductor for different incoming photon energies. For this means there are analyzed main Compton broadening processes in semiconductor Cd 0,8 Zn 0,2 Te with density ρ=5,85g/cm 3 . (Author)

  16. Thermal Characterization and Optimization of the Pixel Module Support Structure for the Phase-1 Upgrade of the CMS Pixel Detector

    CERN Document Server

    AUTHOR|(CDS)2094386; Feld, Lutz Werner

    2015-01-01

    The CMS (Compact Muon Solenoid) pixel detector is used in CMS for the vertex reconstruction of events in high-energy proton-proton collisions produced by the Large Hadron Collider (LHC). It is planned for the future years that the LHC will deliver significantly higher instantaneous and integrated luminosities. Therefore, also the demands and requirements for the participating detectors rise. Thus the current CMS pixel detector will be replaced by the CMS Phase-1 Upgrade Pixel Detector in the extended year-end technical stop in winter 2016/2017. As a vertex detector, the pixel detector is the innermost detector component and it is located at a short distance to the proton-proton interaction point. Therefore it has to cope with high particle hit rates and high irradiation. The heat produced due to power consumption has to be removed while using a low-mass detector design. The low-mass design of the Phase-1 Upgrade Pixel Detector will be implemented by utilizing a new two-phase CO2 cooling concept and an ultra l...

  17. Pixel detectors for x-ray imaging spectroscopy in space

    International Nuclear Information System (INIS)

    Treis, J; Andritschke, R; Hartmann, R; Herrmann, S; Holl, P; Lauf, T; Lechner, P; Lutz, G; Meidinger, N; Porro, M; Richter, R H; Schopper, F; Soltau, H; Strueder, L

    2009-01-01

    Pixelated semiconductor detectors for X-ray imaging spectroscopy are foreseen as key components of the payload of various future space missions exploring the x-ray sky. Located on the platform of the new Spectrum-Roentgen-Gamma satellite, the eROSITA (extended Roentgen Survey with an Imaging Telescope Array) instrument will perform an imaging all-sky survey up to an X-ray energy of 10 keV with unprecedented spectral and angular resolution. The instrument will consist of seven parallel oriented mirror modules each having its own pnCCD camera in the focus. The satellite born X-ray observatory SIMBOL-X will be the first mission to use formation-flying techniques to implement an X-ray telescope with an unprecedented focal length of around 20 m. The detector instrumentation consists of separate high- and low energy detectors, a monolithic 128 x 128 DEPFET macropixel array and a pixellated CdZTe detector respectively, making energy band between 0.5 to 80 keV accessible. A similar concept is proposed for the next generation X-ray observatory IXO. Finally, the MIXS (Mercury Imaging X-ray Spectrometer) instrument on the European Mercury exploration mission BepiColombo will use DEPFET macropixel arrays together with a small X-ray telescope to perform a spatially resolved planetary XRF analysis of Mercury's crust. Here, the mission concepts and their scientific targets are briefly discussed, and the resulting requirements on the detector devices together with the implementation strategies are shown.

  18. Pixel detectors for x-ray imaging spectroscopy in space

    Science.gov (United States)

    Treis, J.; Andritschke, R.; Hartmann, R.; Herrmann, S.; Holl, P.; Lauf, T.; Lechner, P.; Lutz, G.; Meidinger, N.; Porro, M.; Richter, R. H.; Schopper, F.; Soltau, H.; Strüder, L.

    2009-03-01

    Pixelated semiconductor detectors for X-ray imaging spectroscopy are foreseen as key components of the payload of various future space missions exploring the x-ray sky. Located on the platform of the new Spectrum-Roentgen-Gamma satellite, the eROSITA (extended Roentgen Survey with an Imaging Telescope Array) instrument will perform an imaging all-sky survey up to an X-ray energy of 10 keV with unprecedented spectral and angular resolution. The instrument will consist of seven parallel oriented mirror modules each having its own pnCCD camera in the focus. The satellite born X-ray observatory SIMBOL-X will be the first mission to use formation-flying techniques to implement an X-ray telescope with an unprecedented focal length of around 20 m. The detector instrumentation consists of separate high- and low energy detectors, a monolithic 128 × 128 DEPFET macropixel array and a pixellated CdZTe detector respectively, making energy band between 0.5 to 80 keV accessible. A similar concept is proposed for the next generation X-ray observatory IXO. Finally, the MIXS (Mercury Imaging X-ray Spectrometer) instrument on the European Mercury exploration mission BepiColombo will use DEPFET macropixel arrays together with a small X-ray telescope to perform a spatially resolved planetary XRF analysis of Mercury's crust. Here, the mission concepts and their scientific targets are briefly discussed, and the resulting requirements on the detector devices together with the implementation strategies are shown.

  19. Pixel detectors for x-ray imaging spectroscopy in space

    Energy Technology Data Exchange (ETDEWEB)

    Treis, J; Andritschke, R; Hartmann, R; Herrmann, S; Holl, P; Lauf, T; Lechner, P; Lutz, G; Meidinger, N; Porro, M; Richter, R H; Schopper, F; Soltau, H; Strueder, L [MPI Semiconductor Laboratory, Otto-Hahn-Ring 6, D-81739 Munich (Germany)], E-mail: jft@hll.mpg.de

    2009-03-15

    Pixelated semiconductor detectors for X-ray imaging spectroscopy are foreseen as key components of the payload of various future space missions exploring the x-ray sky. Located on the platform of the new Spectrum-Roentgen-Gamma satellite, the eROSITA (extended Roentgen Survey with an Imaging Telescope Array) instrument will perform an imaging all-sky survey up to an X-ray energy of 10 keV with unprecedented spectral and angular resolution. The instrument will consist of seven parallel oriented mirror modules each having its own pnCCD camera in the focus. The satellite born X-ray observatory SIMBOL-X will be the first mission to use formation-flying techniques to implement an X-ray telescope with an unprecedented focal length of around 20 m. The detector instrumentation consists of separate high- and low energy detectors, a monolithic 128 x 128 DEPFET macropixel array and a pixellated CdZTe detector respectively, making energy band between 0.5 to 80 keV accessible. A similar concept is proposed for the next generation X-ray observatory IXO. Finally, the MIXS (Mercury Imaging X-ray Spectrometer) instrument on the European Mercury exploration mission BepiColombo will use DEPFET macropixel arrays together with a small X-ray telescope to perform a spatially resolved planetary XRF analysis of Mercury's crust. Here, the mission concepts and their scientific targets are briefly discussed, and the resulting requirements on the detector devices together with the implementation strategies are shown.

  20. Measurement of the position resolution of the Gas Pixel Detector

    International Nuclear Information System (INIS)

    Soffitta, Paolo; Muleri, Fabio; Fabiani, Sergio; Costa, Enrico; Bellazzini, Ronaldo; Brez, Alessandro; Minuti, Massimo; Pinchera, Michele; Spandre, Gloria

    2013-01-01

    The Gas Pixel Detector was designed and built as a focal plane instrument for X-ray polarimetry of celestial sources, the last unexplored subtopics of X-ray astronomy. It promises to perform detailed and sensitive measurements resolving extended sources and detecting polarization in faint sources in crowded fields at the focus of telescopes of good angular resolution. Its polarimetric and spectral capability were already studied in earlier works. Here we investigate for the first time, with both laboratory measurements and Monte Carlo simulations, its imaging properties to confirm its unique capability to carry out imaging spectral-polarimetry in future X-ray missions.

  1. Radiation damage of pixelated photon detector by neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Isamu [KEK, 1-1 Oho Tsukuba 305-0801 (Japan)], E-mail: isamu.nakamura@kek.jp

    2009-10-21

    Radiation Damage of Pixelated Photon Detector by neutron irradiation is reported. MPPC, one of PPD or Geiger-mode APD, developed by Hamamatsu Photonics, is planned to be used in many high energy physics experiments. In such experiments radiation damage is a serious issue. A series of neutron irradiation tests is performed at the Reactor YAYOI of the University of Tokyo. MPPCs were irradiated at the reactor up to 10{sup 12}neutron/cm{sup 2}. In this paper, the effect of neutron irradiation on the basic characteristics of PPD including gain, noise rate, photon detection efficiency is presented.

  2. Pixel detector modules using MCM-D technology

    CERN Document Server

    Grah, C

    2001-01-01

    For the upcoming ATLAS-experiment at CERN it is planned to build a large area pixel detector, providing more than 100*10/sup 6/ sensor cells. For the innermost layer, the B-physics layer, it is planned to use MCM-D technology to perform the signal interconnections and power distribution on the modules. Focus of this paper is to give an introduction to this technology and present measurements on single chip MCM-D assemblies and a full scale MCM-D module prototype. (10 refs).

  3. Silicon pixel-detector R&D for CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)718101

    2016-01-01

    The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few μm, ultra-low mass (∼ 0.2% X${}_0$ per layer for the vertex region and ∼ 1 % X${}_0$ per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ∼ 10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hybrid pixel detectors with small pitch (25 μm) and analog readout are explored. For the outer trac...

  4. Silicon pixel R&D for the CLIC detector

    CERN Document Server

    AUTHOR|(SzGeCERN)674552

    2017-01-01

    The physics aims at the future CLIC high-energy linear $e^{+}e^{−}$ collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The main challenges are: a point resolution of a few microns, ultra-low mass (~0.2% X$_{0}$ per layer for the vertex region and ~1% X$_{0}$ per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ~10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hybrid pixel detectors with small pitch (25 μm) and analogue readout are explored. For the outer tra...

  5. Characterization of Si pixel detectors of different thickness

    Energy Technology Data Exchange (ETDEWEB)

    Bisogni, M.G.; Boscardin, M.; Dalla Betta, G.F.; Delogu, P.; Fantacci, M.E.; Gregori, P.; Linsalata, S.; Novelli, M. E-mail: marzia.novelli@pi.infn.it; Piemonte, C.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Zorzi, N.; Zucca, S

    2004-02-01

    Tests on silicon pixel detector in the mammographic energy range have shown good imaging performances so, in order to improve the efficiency in this energy range, we have designed thicker detectors of the p{sup +}/n type. The detectors have been fabricated by ITC-IRST (Trento, Italy) in high resistivity silicon substrates (300 and 525 {mu}m thick). A TCAD simulation work has been carried out to optimize the electric field distribution and to enhance the breakdown voltage. Very low leakage current and high breakdown voltage characteristics have been measured on detectors in preliminary on-wafer tests. After that, detectors have been bump-bonded to a dedicated VLSI electronic chips, realizing an assembly. Choosing the best set-up condition and using a standard mammographic tube, we have acquired a large area image (8x8 cm{sup 2}) of the RMI 156 phantom, recommended for mammographic quality checks. In order to cover the whole surface, we have acquired different images translating the phantom over the assembly. We present some selected results for these assemblies both for the electrical characteristics and for the imaging performances.

  6. Characterization of Si pixel detectors of different thickness

    International Nuclear Information System (INIS)

    Bisogni, M.G.; Boscardin, M.; Dalla Betta, G.F.; Delogu, P.; Fantacci, M.E.; Gregori, P.; Linsalata, S.; Novelli, M.; Piemonte, C.; Quattrocchi, M.; Rosso, V.; Stefanini, A.; Zorzi, N.; Zucca, S.

    2004-01-01

    Tests on silicon pixel detector in the mammographic energy range have shown good imaging performances so, in order to improve the efficiency in this energy range, we have designed thicker detectors of the p + /n type. The detectors have been fabricated by ITC-IRST (Trento, Italy) in high resistivity silicon substrates (300 and 525 μm thick). A TCAD simulation work has been carried out to optimize the electric field distribution and to enhance the breakdown voltage. Very low leakage current and high breakdown voltage characteristics have been measured on detectors in preliminary on-wafer tests. After that, detectors have been bump-bonded to a dedicated VLSI electronic chips, realizing an assembly. Choosing the best set-up condition and using a standard mammographic tube, we have acquired a large area image (8x8 cm 2 ) of the RMI 156 phantom, recommended for mammographic quality checks. In order to cover the whole surface, we have acquired different images translating the phantom over the assembly. We present some selected results for these assemblies both for the electrical characteristics and for the imaging performances

  7. Development of a cadmium telluride pixel detector for astrophysical applications

    Science.gov (United States)

    Miyasaka, Hiromasa; Harrison, Fiona A.; Cook, Walter R.; Mao, Peter H.; Rana, Vikram R.; Ishikawa, Shin-Nosuke; Ushio, Masayoshi; Aono, Hiroyuki; Watanabe, Shin; Sato, Goro; Kokubun, Motohide; Takahashi, Tadayuki

    2009-08-01

    We are developing imaging Cadmium Telluride (CdTe) pixel detectors optimized for astrophysical hard X-ray applications. Our hybrid detector consist of a CdTe crystal 1mm thick and 2cm × 2cm in area with segmented anode contacts directly bonded to a custom low-noise application specific integrated circuit (ASIC). The CdTe sensor, fabricated by ACRORAD (Okinawa, Japan), has Schottky blocking contacts on a 605 micron pitch in a 32 × 32 array, providing low leakage current and enabling readout of the anode side. The detector is bonded using epoxy-gold stud interconnects to a custom low noise, low power ASIC circuit developed by Caltech's Space Radiation Laboratory. We have achieved very good energy resolution over a wide energy range (0.62keV FWHM @ 60keV, 10.8keV FWHM @ 662keV). We observe polarization effects at room temperature, but they are suppressed if we operate the detector at or below 0°C degree. These detectors have potential application for future missions such as the International X-ray Observatory (IXO).

  8. Simulation of the Dynamic Inefficiency of the CMS Pixel Detector

    CERN Document Server

    INSPIRE-00380273

    2015-05-07

    The Pixel Detector is the innermost part of the CMS Tracker. It therefore has to prevail in the harshest environment in terms of particle fluence and radiation. There are several mechanisms that may decrease the efficiency of the detector. These are mainly caused by data acquisition (DAQ) problems and/or Single Event Upsets (SEU). Any remaining efficiency loss is referred to as the dynamic inefficiency. It is caused by various mechanisms inside the Readout Chip (ROC) and depends strongly on the data occupancy. In the 2012 data, at high values of instantaneous luminosity the inefficiency reached 2\\% (in the region closest to the interaction point) which is not negligible. In the 2015 run higher instantaneous luminosity is expected, which will result in lower efficiencies; therefore this effect needs to be understood and simulated. A data-driven method has been developed to simulate dynamic inefficiency, which has been shown to successfully simulate the effects.

  9. Development of a Detector Control System for the ATLAS Pixel detector in the HL-LHC

    International Nuclear Information System (INIS)

    Lehmann, N.; Kersten, S.; Zeitnitz, C.; Karagounis, M.

    2016-01-01

    The upgrade of the LHC to the HL-LHC requires a new ITk detector. The innermost part of this new tracker is a pixel detector. The University of Wuppertal is developing a new DCS to monitor and control this new pixel detector. The current concept envisions three parallel paths of the DCS. The first path, called security path, is hardwired and provides an interlock system to guarantee the safety of the detector and human beings. The second path is a control path. This path is used to supervise the entire detector. The control path has its own communication lines independent from the regular data readout for reliable operation. The third path is for diagnostics and provides information on demand. It is merged with the regular data readout and provides the highest granularity and most detailed information. To reduce the material budget, a serial power scheme is the baseline for the pixel modules. A new ASIC used in the control path is in development at Wuppertal for this serial power chain. A prototype exists already and a proof of principle was demonstrated. Development and research is ongoing to guarantee the correct operation of the new ASIC in the harsh environment of the HL-LHC. The concept for the new DCS will be presented in this paper. A focus will be made on the development of the DCS chip, used for monitoring and control of pixel modules in a serial power chain.

  10. Pixelated transmission-mode diamond X-ray detector.

    Science.gov (United States)

    Zhou, Tianyi; Ding, Wenxiang; Gaowei, Mengjia; De Geronimo, Gianluigi; Bohon, Jen; Smedley, John; Muller, Erik

    2015-11-01

    Fabrication and testing of a prototype transmission-mode pixelated diamond X-ray detector (pitch size 60-100 µm), designed to simultaneously measure the flux, position and morphology of an X-ray beam in real time, are described. The pixel density is achieved by lithographically patterning vertical stripes on the front and horizontal stripes on the back of an electronic-grade chemical vapor deposition single-crystal diamond. The bias is rotated through the back horizontal stripes and the current is read out on the front vertical stripes at a rate of ∼ 1 kHz, which leads to an image sampling rate of ∼ 30 Hz. This novel signal readout scheme was tested at beamline X28C at the National Synchrotron Light Source (white beam, 5-15 keV) and at beamline G3 at the Cornell High Energy Synchrotron Source (monochromatic beam, 11.3 keV) with incident beam flux ranges from 1.8 × 10(-2) to 90 W mm(-2). Test results show that the novel detector provides precise beam position (positional noise within 1%) and morphology information (error within 2%), with an additional software-controlled single channel mode providing accurate flux measurement (fluctuation within 1%).

  11. Tests of the gated mode for Belle II pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Prinker, Eduard [Max-Planck-Institute for Physics, Munich (Germany); Collaboration: Belle II-Collaboration

    2015-07-01

    DEPFET pixel detectors offer intrinsic amplification and very high signal to noise ratio. They form an integral building block for the vertex detector system of the Belle II experiment, which will start data taking in the year 2017 at the SuperKEKB Collider in Japan. A special Test board (Hybrid4) is used, which contains a small version of the DEPFET sensor with a read-out (DCD) and a steering chip (Switcher) attached, both controlled by a field-programmable gate array (FPGA) as the central interface to the computer. In order to keep the luminosity of the collider constant over time, the particle bunch currents have to be topped off by injecting additional bunches at a rate of 50 Hz. The particles in the daughter bunches produce a high rate of background (noisy bunches) for a short period of time, saturating the occupancy of the sensor. Operating the DEPFET sensor in a Gated Mode allows preserving the signals from collisions of normal bunches while protecting the pixels from background signals of the passing noisy bunches. An overview of the Gated Mode and first results is presented.

  12. Fine-scale spatial response of CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Brunett, B.A.; Van Scyoc, J.M.; Hilton, N.R.; Lund, J.C.; James, R.B.; Schlesinger, T.E.

    1998-01-01

    Several studies have suggested that the uniformity of Cadmium Zinc Telluride (CZT) detectors play an important role in their performance when operated as gamma-ray spectrometers. However the detailed gamma response of simple planar detectors as a function of position over the device area is largely unknown. To address this issue the authors have built a system capable of measuring the detector response with a resolution of ∼250 (micro)m. The system consists of a highly collimated (∼200 (micro)m) photon source (<150 kev) scanned over the detector using a computer controlled two-axis translation stage. Fifteen samples configured as planar detectors were examined with the new apparatus. The material grade of the detectors examined varied from counter to select discriminator. Two classes of spatial response variation were observed and are presented here. Infrared (IR) transmission images were also acquired for each sample and correlation between features in the pulse height spectrum and crystalline defects were observed

  13. Charge amplitude distribution of the Gossip gaseous pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Blanco Carballo, V.M. [Twente University, Enschede (Netherlands); Chefdeville, M. [NIKHEF, P.B. 41882, 1009DB Amsterdam (Netherlands); Colas, P.; Giomataris, Y. [Saclay, Gif-sur-Yvette (France); Graaf, H. van der; Gromov, V. [NIKHEF, P.B. 41882, 1009DB Amsterdam (Netherlands); Hartjes, F. [NIKHEF, P.B. 41882, 1009DB Amsterdam (Netherlands)], E-mail: F.Hartjes@nikhef.nl; Kluit, R.; Koffeman, E. [NIKHEF, P.B. 41882, 1009DB Amsterdam (Netherlands); Salm, C.; Schmitz, J.; Smits, S.M. [Twente University, Enschede (Netherlands); Timmermans, J.; Visschers, J.L. [NIKHEF, P.B. 41882, 1009DB Amsterdam (Netherlands)

    2007-12-11

    The Gossip gaseous pixel detector is being developed for the detection of charged particles in extreme high radiation environments as foreseen close to the interaction point of the proposed super LHC. The detecting medium is a thin layer of gas. Because of the low density of this medium, only a few primary electron/ion pairs are created by the traversing particle. To get a detectable signal, the electrons drift towards a perforated metal foil (Micromegas) whereafter they are multiplied in a gas avalanche to provide a detectable signal. The gas avalanche occurs in the high field between the Micromegas and the pixel readout chip (ROC). Compared to a silicon pixel detector, Gossip features a low material budget and a low cooling power. An experiment using X-rays has indicated a possible high radiation tolerance exceeding 10{sup 16} hadrons/cm{sup 2}. The amplified charge signal has a broad amplitude distribution due to the limited statistics of the primary ionization and the statistical variation of the gas amplification. Therefore, some degree of inefficiency is inevitable. This study presents experimental results on the charge amplitude distribution for CO{sub 2}/DME (dimethyl-ether) and Ar/iC{sub 4}H{sub 10} mixtures. The measured curves were fitted with the outcome of a theoretical model. In the model, the physical Landau distribution is approximated by a Poisson distribution that is convoluted with the variation of the gas gain and the electronic noise. The value for the fraction of pedestal events is used for a direct calculation of the cluster density. For some gases, the measured cluster density is considerably lower than given in literature.

  14. Charge amplitude distribution of the Gossip gaseous pixel detector

    Science.gov (United States)

    Blanco Carballo, V. M.; Chefdeville, M.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Gromov, V.; Hartjes, F.; Kluit, R.; Koffeman, E.; Salm, C.; Schmitz, J.; Smits, S. M.; Timmermans, J.; Visschers, J. L.

    2007-12-01

    The Gossip gaseous pixel detector is being developed for the detection of charged particles in extreme high radiation environments as foreseen close to the interaction point of the proposed super LHC. The detecting medium is a thin layer of gas. Because of the low density of this medium, only a few primary electron/ion pairs are created by the traversing particle. To get a detectable signal, the electrons drift towards a perforated metal foil (Micromegas) whereafter they are multiplied in a gas avalanche to provide a detectable signal. The gas avalanche occurs in the high field between the Micromegas and the pixel readout chip (ROC). Compared to a silicon pixel detector, Gossip features a low material budget and a low cooling power. An experiment using X-rays has indicated a possible high radiation tolerance exceeding 10 16 hadrons/cm 2. The amplified charge signal has a broad amplitude distribution due to the limited statistics of the primary ionization and the statistical variation of the gas amplification. Therefore, some degree of inefficiency is inevitable. This study presents experimental results on the charge amplitude distribution for CO 2/DME (dimethyl-ether) and Ar/iC 4H 10 mixtures. The measured curves were fitted with the outcome of a theoretical model. In the model, the physical Landau distribution is approximated by a Poisson distribution that is convoluted with the variation of the gas gain and the electronic noise. The value for the fraction of pedestal events is used for a direct calculation of the cluster density. For some gases, the measured cluster density is considerably lower than given in literature.

  15. Charge amplitude distribution of the Gossip gaseous pixel detector

    International Nuclear Information System (INIS)

    Blanco Carballo, V.M.; Chefdeville, M.; Colas, P.; Giomataris, Y.; Graaf, H. van der; Gromov, V.; Hartjes, F.; Kluit, R.; Koffeman, E.; Salm, C.; Schmitz, J.; Smits, S.M.; Timmermans, J.; Visschers, J.L.

    2007-01-01

    The Gossip gaseous pixel detector is being developed for the detection of charged particles in extreme high radiation environments as foreseen close to the interaction point of the proposed super LHC. The detecting medium is a thin layer of gas. Because of the low density of this medium, only a few primary electron/ion pairs are created by the traversing particle. To get a detectable signal, the electrons drift towards a perforated metal foil (Micromegas) whereafter they are multiplied in a gas avalanche to provide a detectable signal. The gas avalanche occurs in the high field between the Micromegas and the pixel readout chip (ROC). Compared to a silicon pixel detector, Gossip features a low material budget and a low cooling power. An experiment using X-rays has indicated a possible high radiation tolerance exceeding 10 16 hadrons/cm 2 . The amplified charge signal has a broad amplitude distribution due to the limited statistics of the primary ionization and the statistical variation of the gas amplification. Therefore, some degree of inefficiency is inevitable. This study presents experimental results on the charge amplitude distribution for CO 2 /DME (dimethyl-ether) and Ar/iC 4 H 10 mixtures. The measured curves were fitted with the outcome of a theoretical model. In the model, the physical Landau distribution is approximated by a Poisson distribution that is convoluted with the variation of the gas gain and the electronic noise. The value for the fraction of pedestal events is used for a direct calculation of the cluster density. For some gases, the measured cluster density is considerably lower than given in literature

  16. Diamond Pixel Detectors and 3D Diamond Devices

    International Nuclear Information System (INIS)

    Venturi, N.

    2016-01-01

    Results from detectors of poly-crystalline chemical vapour deposited (pCVD) diamond are presented. These include the first analysis of data of the ATLAS Diamond Beam Monitor (DBM). The DBM module consists of pCVD diamond sensors instrumented with pixellated FE-I4 front-end electronics. Six diamond telescopes, each with three modules, are placed symmetrically around the ATLAS interaction point. The DBM tracking capabilities allow it to discriminate between particles coming from the interaction point and background particles passing through the ATLAS detector. Also, analysis of test beam data of pCVD DBM modules are presented. A new low threshold tuning algorithm based on noise occupancy was developed which increases the DBM module signal to noise ratio significantly. Finally first results from prototypes of a novel detector using pCVD diamond and resistive electrodes in the bulk, forming a 3D diamond device, are discussed. 3D devices based on pCVD diamond were successfully tested with test beams at CERN. The measured charge is compared to that of a strip detector mounted on the same pCVD diamond showing that the 3D device collects significantly more charge than the planar device.

  17. Optimization of the thermal performances of the Alpine Pixel Detector

    CERN Document Server

    Zhang, Zhan; Di Ciaccio, Lucia

    The ATLAS (A Toroidal LHC ApparatuS) detector is the largest detector of the Large Hadron Collider (LHC). One of the most important goals of ATLAS was to search for the missing piece of the Standard Model, the Higgs boson that had been found in 2012. In order to keep looking for the unknowns, it is planned to upgrade the LHC. The High Luminosity LHC (HL-LHC) is a novel configuration of the accelerator, aiming at increasing the luminosity by a factor five or more above the nominal LHC design. In parallel with the accelerator upgrade also the ATLAS will be upgraded to cope with detector aging and to achieve the same or better performance under increased event rate and radiation dose expected at the HL-LHC. This thesis discusses a novel design for the ATLAS Pixel Detector called the "Alpine" layout for the HL-LHC. To support this design, a local support structure is proposed, optimized and tested with an advanced CO2 evaporative cooling system. A numerical program called “CoBra” simulating the twophase heat ...

  18. Development and characterization of diamond and 3D-silicon pixel detectors with ATLAS-pixel readout electronics

    Energy Technology Data Exchange (ETDEWEB)

    Mathes, Markus

    2008-12-15

    Hybrid pixel detectors are used for particle tracking in the innermost layers of current high energy experiments like ATLAS. After the proposed luminosity upgrade of the LHC, they will have to survive very high radiation fluences of up to 10{sup 16} particles per cm{sup 2} per life time. New sensor concepts and materials are required, which promise to be more radiation tolerant than the currently used planar silicon sensors. Most prominent candidates are so-called 3D-silicon and single crystal or poly-crystalline diamond sensors. Using the ATLAS pixel electronics different detector prototypes with a pixel geometry of 400 x 50 {mu}m{sup 2} have been built. In particular three devices have been studied in detail: a 3D-silicon and a single crystal diamond detector with an active area of about 1 cm{sup 2} and a poly-crystalline diamond detector of the same size as a current ATLAS pixel detector module (2 x 6 cm{sup 2}). To characterize the devices regarding their particle detection efficiency and spatial resolution, the charge collection inside a pixel cell as well as the charge sharing between adjacent pixels was studied using a high energy particle beam. (orig.)

  19. Development and characterization of diamond and 3D-silicon pixel detectors with ATLAS-pixel readout electronics

    International Nuclear Information System (INIS)

    Mathes, Markus

    2008-12-01

    Hybrid pixel detectors are used for particle tracking in the innermost layers of current high energy experiments like ATLAS. After the proposed luminosity upgrade of the LHC, they will have to survive very high radiation fluences of up to 10 16 particles per cm 2 per life time. New sensor concepts and materials are required, which promise to be more radiation tolerant than the currently used planar silicon sensors. Most prominent candidates are so-called 3D-silicon and single crystal or poly-crystalline diamond sensors. Using the ATLAS pixel electronics different detector prototypes with a pixel geometry of 400 x 50 μm 2 have been built. In particular three devices have been studied in detail: a 3D-silicon and a single crystal diamond detector with an active area of about 1 cm 2 and a poly-crystalline diamond detector of the same size as a current ATLAS pixel detector module (2 x 6 cm 2 ). To characterize the devices regarding their particle detection efficiency and spatial resolution, the charge collection inside a pixel cell as well as the charge sharing between adjacent pixels was studied using a high energy particle beam. (orig.)

  20. Study on Characteristic of CdZnTe Semiconductor Detectors for Alpha Particle Measurement

    International Nuclear Information System (INIS)

    Kang, Sang Mook; Ha, Jang Ho; Kim, Yong Kyun; Park, Se Hwan; Kim, Han Soo; Chung, Chong Eun

    2005-01-01

    The last 2-3 years have seen continued effort in the development of a wide band gap room-temperature compound semiconductor devices aimed principally at photon imaging covering hard X-rays, synchrotrons, and low to medium energy gamma rays. Especially, among the semiconductor materials of a wide band gap, CdZnTe(CZT) has commonly used X-ray and gammaray detection applications because of the opportunity to achieve and excellent spectral and spatial resolution. It has recently been demonstrated that CZT can be used as an ancillary detector with the ability to detect both alpha particles and X-ray at room temperature. CZT detectors are relatively inexpensive compared with some silicon detectors, and are priced about the same as amorphous silicon and photodiodes which are routinely used for charged particle detection. In this paper, we investigated the use of the CZT semiconductor material as an alpha particles detector

  1. Development of (Cd,Zn)Te X-ray and gamma ray radiation detectors for medical and security applications

    International Nuclear Information System (INIS)

    Franc, J.; Hoeschl, P.; Belas, E.; Grill, V.; Fauler, A.; Dambacher, M.; Procz, S.

    2011-01-01

    Full text: There is a growing need for large area X-and Gamma radiation detectors for penetrating radiations in various fields of application e.g. astronomy, detectors for nuclear medicine, biosensor materials, security, non-proliferation of hazardous materials, and environmental applications etc. Direct X-rays conversion into electric charges in a semiconductor is envisaged with better spectroscopic characteristics to improve contrast and quantitative measurements compared to indirect detection using scintillators. The family of II-VI semiconductor materials combine a range of excellent properties such as their high sensitivity due to the high mobility-lifetime products, their high energy resolution as a consequence of the electron-hole pair formation energy, their reasonable maturity in terms of microelectronic technologies required for commercial detector fabrication, wide range of stopping power and band-gaps available. In particular, CdTe and Cd x Zn 1-x Te (CZT) with Zn=0.1 offer a favorable combination of physical and chemical properties that makes it attractive as a room temperature X-ray detector material of choice for many applications involving photon energies up to several hundreds of keV. From the scientific experience accumulated in the past years, the detector properties are strongly dependent on a series of parameters which must be strictly controlled during crystal growth, such as the homogeneity, stoichiometry and the related intrinsic defects which appear during the material growth, a high mobility-lifetime for electron and holes is mandatory etc. Production of detector-grade CdTe and CdZnTe on industrial scale is still a challenge and optimal growth methods and growth conditions have been under intensive investigation. Progress in crystal growth and characterization achieved in a project of Institute partnership between Charles University in Prague and University of Freiburg, Germany which was sponsored by Alexander von Humboldt Foundation, will

  2. Active pixel sensor array as a detector for electron microscopy.

    Science.gov (United States)

    Milazzo, Anna-Clare; Leblanc, Philippe; Duttweiler, Fred; Jin, Liang; Bouwer, James C; Peltier, Steve; Ellisman, Mark; Bieser, Fred; Matis, Howard S; Wieman, Howard; Denes, Peter; Kleinfelder, Stuart; Xuong, Nguyen-Huu

    2005-09-01

    A new high-resolution recording device for transmission electron microscopy (TEM) is urgently needed. Neither film nor CCD cameras are systems that allow for efficient 3-D high-resolution particle reconstruction. We tested an active pixel sensor (APS) array as a replacement device at 200, 300, and 400 keV using a JEOL JEM-2000 FX II and a JEM-4000 EX electron microscope. For this experiment, we used an APS prototype with an area of 64 x 64 pixels of 20 microm x 20 microm pixel pitch. Single-electron events were measured by using very low beam intensity. The histogram of the incident electron energy deposited in the sensor shows a Landau distribution at low energies, as well as unexpected events at higher absorbed energies. After careful study, we concluded that backscattering in the silicon substrate and re-entering the sensitive epitaxial layer a second time with much lower speed caused the unexpected events. Exhaustive simulation experiments confirmed the existence of these back-scattered electrons. For the APS to be usable, the back-scattered electron events must be eliminated, perhaps by thinning the substrate to less than 30 microm. By using experimental data taken with an APS chip with a standard silicon substrate (300 microm) and adjusting the results to take into account the effect of a thinned silicon substrate (30 microm), we found an estimate of the signal-to-noise ratio for a back-thinned detector in the energy range of 200-400 keV was about 10:1 and an estimate for the spatial resolution was about 10 microm.

  3. Multichannel CdZnTe Gamma Ray Spectrometer

    International Nuclear Information System (INIS)

    Doty, F.P.; Lingren, C. L.; Apotovsky, B. A.; Brunsch, J.; Butler, J. F.; Collins, T.; Conwell, R.L.; Friesenhahn, S.; Gormley, J.; Pi, B.; Zhao, S.; Augustine, F.L.; Bennet, B. A.; Cross, E.; James, R. B.

    1998-01-01

    A 3 cm 3 multichannel gamma spectrometer for DOE applications is under development by Digirad Corporation. The device is based on a position sensitive detector packaged in a compact multi-chip module (MCM) with integrated readout circuitry. The modular, multichannel design will enable identification and quantitative analysis of radionuclides in extended sources, or sources containing low levels of activity. The MCM approach has the advantages that the modules are designed for imaging applications, and the sensitivity can be arbitrarily increased by increasing the number of pixels, i.e. adding modules to the instrument. For a high sensitivity probe, the outputs for each pixel can be corrected for gain and offset variations, and summed digitally. Single pixel results obtained with discrete low noise readout indicate energy resolution of 3 keV can be approached with currently available CdZnTe. The energy resolution demonstrated to date with MCMs for 511 keV gamma rays is 10 keV

  4. Towards a new generation of pixel detector readout chips

    CERN Document Server

    Campbell, M; Ballabriga, R.; Frojdh, E.; Heijne, E.; Llopart, X.; Poikela, T.; Tlustos, L.; Valerio, P.; Wong, W.

    2016-01-01

    The Medipix3 Collaboration has broken new ground in spectroscopic X-ray imaging and in single particle detection and tracking. This paper will review briefly the performance and limitations of the present generation of pixel detector readout chips developed by the Collaboration. Through Silicon Via technology has the potential to provide a significant improvement in the tile- ability and more flexibility in the choice of readout architecture. This has been explored in the context of 3 projects with CEA-LETI using Medipix3 and Timepix3 wafers. The next generation of chips will aim to provide improved spectroscopic imaging performance at rates compatible with human CT. It will also aim to provide full spectroscopic images with unprecedented energy and spatial resolution. Some of the opportunities and challenges posed by moving to a more dense CMOS process will be discussed.

  5. Thin and edgeless sensors for ATLAS pixel detector upgrade

    Science.gov (United States)

    Ducourthial, A.; Bomben, M.; Calderini, G.; Marchiori, G.; D'Eramo, L.; Luise, I.; Bagolini, A.; Boscardin, M.; Bosisio, L.; Darbo, G.; Dalla Betta, G.-F.; Giacomini, G.; Meschini, M.; Messineo, A.; Ronchin, S.; Zorzi, N.

    2017-12-01

    To cope with the harsh environment foreseen at the high luminosity conditions of HL-LHC, the ATLAS pixel detector has to be upgraded to be fully efficient with a good granularity, a maximized geometrical acceptance and an high read out rate. LPNHE, FBK and INFN are involved in the development of thin and edgeless planar pixel sensors in which the insensitive area at the border of the sensor is minimized thanks to the active edge technology. In this paper we report on two productions, a first one consisting of 200 μm thick n-on-p sensors with active edge, a second one composed of 100 and 130 μm thick n-on-p sensors. Those sensors have been tested on beam, both at CERN-SPS and at DESY. In terms of hit-efficiency, the first production reaches 99 % before irradiation and the second one reaches 96.3% after a fluence in excess of 1× 1016neq/cm2. The performances of those two productions before and after irradiation will be presented in details.

  6. Gamma radiation damage in pixelated detector based on carbon nanotubes

    International Nuclear Information System (INIS)

    Leyva, A.; Pinnera, I.; Leyva, D.; Abreu, Y.; Cruz, C. M.

    2013-01-01

    The aim of this paper is to evaluate the possible gamma radiation damage in high pixelated based on multi-walled carbon nanotubes detectors, grown on two different substrata, when it is operating in aggressive radiational environments. The radiation damage in displacements per atom (dpa) terms were calculated using the MCCM algorithm, which takes into account the McKinley-Feshbach approach with the Kinchin-Pease approximation for the damage function. Was observed that with increasing of the gamma energy the displacement total number grows monotonically reaching values of 0.39 displacements for a 10 MeV incident photon. The profiles of point defects distributions inside the carbon nanotube pixel linearly rise with depth, increasing its slope with photon energy. In the 0.1 MeV - 10 MeV studied energy interval the electron contribution to the total displacement number become higher than the positron ones, reaching this last one a maximum value of 12% for the 10 MeV incident photons. Differences between the calculation results for the two used different substrata were not observed. (Author)

  7. Pixel Detector Trial Assembly Test in the SR1 building

    CERN Multimedia

    D. Giugni

    2004-01-01

    During the last two months the Pixel group [LBL, Milan and Wuppertal] made a successful integration test on the mechanics of the barrel. The scope of the test was to qualify the integration procedures and the various assembling tools. The test took place in the clean room of the SR1 building at CERN, where the detector has been assembled around a dummy beam pipe made of Stainless Steel. The process is rather complex: the shells come in two parts and they have to be clamped together to get the full shell. This operation is carried out by a dedicated tool which is shown to the right in the picture below. The layer 1 shell is clamped around a "service" pipe that will be used for moving the full layer to the integration tool [ITT] which is visible on the left. View of the tools devoted to the Pixel barrel integration in the SR1 building Also visible in the picture is the global frame that is actually held by the tool. It will engage the layers sliding onto the rails. The first two layers are sequentially...

  8. X-ray micro-beam characterization of a small pixel spectroscopic CdTe detector

    Science.gov (United States)

    Veale, M. C.; Bell, S. J.; Seller, P.; Wilson, M. D.; Kachkanov, V.

    2012-07-01

    A small pixel, spectroscopic, CdTe detector has been developed at the Rutherford Appleton Laboratory (RAL) for X-ray imaging applications. The detector consists of 80 × 80 pixels on a 250 μm pitch with 50 μm inter-pixel spacing. Measurements with an 241Am γ-source demonstrated that 96% of all pixels have a FWHM of better than 1 keV while the majority of the remaining pixels have FWHM of less than 4 keV. Using the Diamond Light Source synchrotron, a 10 μm collimated beam of monochromatic 20 keV X-rays has been used to map the spatial variation in the detector response and the effects of charge sharing corrections on detector efficiency and resolution. The mapping measurements revealed the presence of inclusions in the detector and quantified their effect on the spectroscopic resolution of pixels.

  9. CdZnTe γ detector for deep inelastic neutron scattering on the VESUVIO spectrometer

    Science.gov (United States)

    Andreani, C.; D'Angelo, A.; Gorini, G.; Imberti, S.; Pietropaolo, A.; Rhodes, N. J.; Schooneveld, E. M.; Senesi, R.; Tardocchi, M.

    In this paper it is shown that solid-state cadmium-zinc-telluride (CZT) is a promising photon detector for neutron spectroscopy in a wide energy interval, ranging from thermal ( 25 meV) to epithermal ( 70 eV) neutron energies. In the present study two CZT detectors were tested as part of the inverse-geometry neutron spectrometer VESUVIO operating at the ISIS pulsed neutron source. The response of the CZT detector to photon emission from radiative neutron capture in 238U was determined by biparametric measurements of neutron time of flight and photon energy. The scattering response function F(y) from a Pb sample has been derived using both CZT and conventional 6Li-glass scintillator detectors. The former showed both an improved signal to background ratio and higher efficiency as compared to 6Li glass, allowing us to measure F(y) up to the fourth 238U absorption energy (Er=66.02 eV). Due to the small size of CZT detectors, their use is envisaged in arrays, with high spatial resolution, for neutron-scattering studies at high energy (ω>1 eV) and low wavevector (q <10 Å-1) transfers.

  10. CdZnTe γ detector for deep inelastic neutron scattering on the VESUVIO spectrometer

    International Nuclear Information System (INIS)

    Andreani, C.; Pietropaolo, A.; Senesi, R.; D'Angelo, A.; Gorini, G.; Imberti, S.; Tardocchi, M.; Rhodes, N.J.; Schooneveld, E.M.

    2004-01-01

    In this paper it is shown that solid-state cadmium-zinc-telluride (CZT) is a promising photon detector for neutron spectroscopy in a wide energy interval, ranging from thermal (∝25 meV) to epithermal (∝70 eV) neutron energies. In the present study two CZT detectors were tested as part of the inverse-geometry neutron spectrometer VESUVIO operating at the ISIS pulsed neutron source. The response of the CZT detector to photon emission from radiative neutron capture in 238 U was determined by biparametric measurements of neutron time of flight and photon energy. The scattering response function F(y) from a Pb sample has been derived using both CZT and conventional 6 Li-glass scintillator detectors. The former showed both an improved signal to background ratio and higher efficiency as compared to 6 Li glass, allowing us to measure F(y) up to the fourth 238 U absorption energy (E r =66.02 eV). Due to the small size of CZT detectors, their use is envisaged in arrays, with high spatial resolution, for neutron-scattering studies at high energy (ℎω>1 eV) and low wavevector (q -1 ) transfers. (orig.)

  11. CdZnTe {gamma} detector for deep inelastic neutron scattering on the VESUVIO spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Andreani, C.; Pietropaolo, A.; Senesi, R. [Dipartimento di Fisica, Universita degli Studi di Roma ' Tor Vergata' , Via della Ricerca Scientifica 1, 00133, Roma (Italy); Istituto Nazionale per la Fisica della Materia, UdR, Tor Vergata (Italy); D' Angelo, A. [Dipartimento di Fisica, Universita degli Studi di Roma ' Tor Vergata' , Via della Ricerca Scientifica 1, 00133, Roma (Italy); Istituto Nazionale di Fisica Nucleare, Sezione, Roma II (Italy); Gorini, G.; Imberti, S.; Tardocchi, M. [Dipartimento di Fisica G. Occhialini, Universita degli Studi di Milano-Bicocca, Piazza della Scienza 3, 20126, Milano (Italy); Istituto Nazionale per la Fisica della Materia, UdR, Milano-Bicocca (Italy); Rhodes, N.J.; Schooneveld, E.M. [Isis Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, Oxfordshire (United Kingdom)

    2004-03-01

    In this paper it is shown that solid-state cadmium-zinc-telluride (CZT) is a promising photon detector for neutron spectroscopy in a wide energy interval, ranging from thermal ({proportional_to}25 meV) to epithermal ({proportional_to}70 eV) neutron energies. In the present study two CZT detectors were tested as part of the inverse-geometry neutron spectrometer VESUVIO operating at the ISIS pulsed neutron source. The response of the CZT detector to photon emission from radiative neutron capture in {sup 238}U was determined by biparametric measurements of neutron time of flight and photon energy. The scattering response function F(y) from a Pb sample has been derived using both CZT and conventional {sup 6}Li-glass scintillator detectors. The former showed both an improved signal to background ratio and higher efficiency as compared to {sup 6}Li glass, allowing us to measure F(y) up to the fourth {sup 238}U absorption energy (E{sub r}=66.02 eV). Due to the small size of CZT detectors, their use is envisaged in arrays, with high spatial resolution, for neutron-scattering studies at high energy ({Dirac_h}{omega}>1 eV) and low wavevector (q <10 A{sup -1}) transfers. (orig.)

  12. Very high resolution detection of gamma radiation at room-temperature using P-I-N detectors of CdZnTe and HgCdTe

    Science.gov (United States)

    Hamilton, W. J.; Rhiger, D. R.; Sen, S.; Kalisher, M. H.; James, K.; Reid, C. P.; Gerrish, V.; Baccash, C. O.

    1994-08-01

    High-energy photon detectors have been constructed by engineering and fabricating p-i-n diode structures consisting of bulk CdZnTe and epitaxial HgCdTe. The p-i-n structure was obtained by liquid-phase epitaxial growth of p and n doped HgCdTe layers on 'intrinsic' CdZnTe material about 1mm thick and approximately 25mm square. Curve tracing shows I-V curves with diode characteristics having resistivity above 1011 Omega -cm and leakage current of less than 400 pA to about - 60V reverse bias on a typical test piece approximately 5 x 8 x 1 mm. Spectra of similar test pieces have been obtained at room temperature with various nuclear isotopic sources over the range of 22 keV to 662 keV which show exceptionally high energy resolution. Resolution as good as 1.82% FWHM was obtained for the 356 keV line of 133Ba with a P/V = 3.4. The performance of these detectors combined with contemporary infrared technology capable of fabricating 2D arrays of these II-VI materials opens up manifold exciting applications in astrophysics, medical, industrial, environmental, and defense spectroscopy and imaging.

  13. Development of a cylindrical tracking detector with multichannel scintillation fibers and pixelated photon detector readout

    Energy Technology Data Exchange (ETDEWEB)

    Akazawa, Y.; Miwa, K.; Honda, R.; Shiozaki, T.; Chiga, N.

    2015-07-01

    We are developing a cylindrical tracking detector for a Σp scattering experiment in J-PARC with scintillation fibers and the Pixelated Photon Detector (PPD) readout, which is called as cylindrical fiber tracker (CFT), in order to reconstruct trajectories of charged particles emitted inside CFT. CFT works not only as a tracking detector but also a particle identification detector from energy deposits. A prototype CFT consisting of two straight layers and one spiral layer was constructed. About 1100 scintillation fibers with a diameter of 0.75 mm (Kuraray SCSF-78 M) were used. Each fiber signal was read by Multi-Pixel Photon Counter (MPPC, HPK S10362-11-050P, 1×1 mm{sup 2}, 400 pixels) fiber by fiber. MPPCs were handled with Extended Analogue Silicon Photomultipliers Integrated ReadOut Chip (EASIROC) boards, which were developed for the readout of a large number of MPPCs. The energy resolution of one layer was 28% for a 70 MeV proton where the energy deposit in fibers was 0.7 MeV.

  14. High-speed readout of high-Z pixel detectors with the LAMBDA detector

    International Nuclear Information System (INIS)

    Pennicard, D.; Smoljanin, S.; Sheviakov, I.; Xia, Q.; Rothkirch, A.; Yu, Y.; Struth, B.; Hirsemann, H.; Graafsma, H.

    2014-01-01

    High-frame-rate X-ray pixel detectors make it possible to perform time-resolved experiments at synchrotron beamlines, and to make better use of these sources by shortening experiment times. LAMBDA is a photon-counting hybrid pixel detector based on the Medipix3 chip, designed to combine a small pixel size of 55 μm, a large tileable module design, high speed, and compatibility with ''high-Z'' sensors for hard X-ray detection. This technical paper focuses on LAMBDA's high-speed-readout functionality, which allows a frame rate of 2000 frames per second with no deadtime between successive images. This takes advantage of the Medipix3 chip's ''continuous read-write'' function and highly parallelised readout. The readout electronics serialise this data and send it back to a server PC over two 10 Gigabit Ethernet links. The server PC controls the detector and receives, processes and stores the data using software designed for the Tango control system. As a demonstration of high-speed readout of a high-Z sensor, a GaAs LAMBDA detector was used to make a high-speed X-ray video of a computer fan

  15. Design and implementation of an expert system for the detector control systems of the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Henss, Tobias

    2008-12-01

    In the framework of this thesis an expert system ''Pixel-Advisor'' for the control system of the pixel detector was designed and implemented. This supports the operational personnel in the diagnosis and removal of possible problems, which are in connection with the detector control system and unburdens the few available DCS experts

  16. Using the pixel detector for fast triggering in CMS

    CERN Document Server

    De Mattai, M

    2006-01-01

    The Standard Model of fundamental interactions (SM) has been extensively tested in many particle experiments during the last 25 years and it has proven to be extremely successful up to the energy scale typical of the weak force. Nevertheless, there is still no experimental evidence of the Higgs boson, one of the key components of the SM, responsible for the breaking of the electroweak symmetry and for the masses of the fermions and of the weak bosons. The Large Hadron Collider (LHC) is scheduled to provide the first proton on proton collision in 2008 at the center of mass energy of 14 Tev, an energy one order of magnitude higher than the regime explored so far. The CMS experiment is an omni-purpose experiment that will operate at the LHC, it will give insight into Standard Model physics and search for physics beyond the Standard Model. In this work we consider the usage of pixel detector information in the reconstruction of hadronic jets in events collected by the CMS detector under high luminosity running co...

  17. From vertex detectors to inner trackers with CMOS pixel sensors

    CERN Document Server

    Besson, A.

    2017-01-01

    The use of CMOS Pixel Sensors (CPS) for high resolution and low material vertex detectors has been validated with the 2014 and 2015 physics runs of the STAR-PXL detector at RHIC/BNL. This opens the door to the use of CPS for inner tracking devices, with 10-100 times larger sensitive area, which require therefore a sensor design privileging power saving, response uniformity and robustness. The 350 nm CMOS technology used for the STAR-PXL sensors was considered as too poorly suited to upcoming applications like the upgraded ALICE Inner Tracking System (ITS), which requires sensors with one order of magnitude improvement on readout speed and improved radiation tolerance. This triggered the exploration of a deeper sub-micron CMOS technology, Tower-Jazz 180 nm, for the design of a CPS well adapted for the new ALICE-ITS running conditions. This paper reports the R&D results for the conception of a CPS well adapted for the ALICE-ITS.

  18. Charge collection and absorption-limited x-ray sensitivity of pixellated x-ray detectors

    International Nuclear Information System (INIS)

    Kabir, M. Zahangir; Kasap, S.O.

    2004-01-01

    The charge collection and absorption-limited x-ray sensitivity of a direct conversion pixellated x-ray detector operating in the presence of deep trapping of charge carriers is calculated using the Shockley-Ramo theorem and the weighting potential of the individual pixel. The sensitivity of a pixellated x-ray detector is analyzed in terms of normalized parameters; (a) the normalized x-ray absorption depth (absorption depth/photoconductor thickness), (b) normalized pixel width (pixel size/thickness), and (c) normalized carrier schubwegs (schubweg/thickness). The charge collection and absorption-limited sensitivity of pixellated x-ray detectors mainly depends on the transport properties (mobility and lifetime) of the charges that move towards the pixel electrodes and the extent of dependence increases with decreasing normalized pixel width. The x-ray sensitivity of smaller pixels may be higher or lower than that of larger pixels depending on the rate of electron and hole trapping and the bias polarity. The sensitivity of pixellated detectors can be improved by ensuring that the carrier with the higher mobility-lifetime product is drifted towards the pixel electrodes

  19. A pixellated gamma-camera based on CdTe detectors clinical interests and performances

    CERN Document Server

    Chambron, J; Eclancher, B; Scheiber, C; Siffert, P; Hage-Ali, M; Regal, R; Kazandjian, A; Prat, V; Thomas, S; Warren, S; Matz, R; Jahnke, A; Karman, M; Pszota, A; Németh, L

    2000-01-01

    A mobile gamma camera dedicated to nuclear cardiology, based on a 15 cmx15 cm detection matrix of 2304 CdTe detector elements, 2.83 mmx2.83 mmx2 mm, has been developed with a European Community support to academic and industrial research centres. The intrinsic properties of the semiconductor crystals - low-ionisation energy, high-energy resolution, high attenuation coefficient - are potentially attractive to improve the gamma-camera performances. But their use as gamma detectors for medical imaging at high resolution requires production of high-grade materials and large quantities of sophisticated read-out electronics. The decision was taken to use CdTe rather than CdZnTe, because the manufacturer (Eurorad, France) has a large experience for producing high-grade materials, with a good homogeneity and stability and whose transport properties, characterised by the mobility-lifetime product, are at least 5 times greater than that of CdZnTe. The detector matrix is divided in 9 square units, each unit is composed ...

  20. CdTe and CdZnTe detectors in nuclear medicine

    CERN Document Server

    Scheiber, C

    2000-01-01

    Nuclear medicine diagnostic applications are growing in search for more disease specific or more physiologically relevant imaging. The data are obtained non-invasively from large field gamma cameras or from miniaturised probes. As far as single photon emitters are concerned, often labelled with sup 9 sup 9 sup m Tc (140 keV, gamma), nuclear instrumentation deals with poor counting statistics due to the method of spatial localisation and low contrast to noise due to scatter in the body. Since the 1960s attempts have been made to replace the NaI scintillator by semiconductor detectors with better spectrometric characteristics to improve contrast and quantitative measurements. They allow direct conversion of energy and thus more compact sensors. Room-temperature semiconductor detectors such as cadmium tellure and cadmium zinc tellure have favourable physical characteristics for medical applications which have been investigated in the 1980s. During one decade, they have been used in miniaturised probes such as fo...

  1. Characterization of CdTe and (CdZn)Te detectors with different metal contacts

    Science.gov (United States)

    Pekárek, J.; Belas, E.; Grill, R.; Uxa, Å.; James, R. B.

    2013-09-01

    In the present work we studied an influence of different types of surface etching and surface passivation of high resistivity CdZnTe-based semiconductor detector material. The aim was to find the optimal conditions to improve the properties of metal-semiconductor contact. The main effort was to reduce the leakage current and thus get better X-ray and gamma-ray spectrum, i.e. to create a detector operating at room temperature based on this semiconductor material with sufficient energy resolution and the maximum charge collection efficiency. Individual surface treatments were characterized by I-V characteristics, spectral analysis and by determination of the profile of the internal electric field.

  2. Pixel detector readout electronics with two-level discriminator scheme

    International Nuclear Information System (INIS)

    Pengg, F.

    1998-01-01

    In preparation for a silicon pixel detector with more than 3,000 readout channels per chip for operation at the future large hadron collider (LHC) at CERN the analog front end of the readout electronics has been designed and measured on several test-arrays with 16 by 4 cells. They are implemented in the HP 0.8 microm process but compatible with the design rules of the radiation hard Honeywell 0.8 microm bulk process. Each cell contains bump bonding pad, preamplifier, discriminator and control logic for masking and testing within a layout area of only 50 microm by 140 microm. A new two-level discriminator scheme has been implemented to cope with the problems of time-walk and interpixel cross-coupling. The measured gain of the preamplifier is 900 mV for a minimum ionizing particle (MIP, about 24,000 e - for a 300 microm thick Si-detector) with a return to baseline within 750 ns for a 1 MIP input signal. The full readout chain (without detector) shows an equivalent noise charge to 60e - r.m.s. The time-walk, a function of the separation between the two threshold levels, is measured to be 22 ns at a separation of 1,500 e - , which is adequate for the 40 MHz beam-crossing frequency at the LHC. The interpixel cross-coupling, measured with a 40fF coupling capacitance, is less than 3%. A single cell consumes 35 microW at 3.5 V supply voltage

  3. Display of cosmic ray event going through the pixel detector taken on October 18th 2008

    CERN Multimedia

    ATLAS, Experiment

    2014-01-01

    Shown are the XY view (of SCT and pixels and of pixels alone) and an RZ view. The track has a hit in each of the layers in both the upper and the lower hemisphere. In the bottom of L0 there are even two hits due to a module overlap. Apart from the signal hits there is only one other hit in the pixel detector demonstrating the very low noise level in the detector.

  4. Development and Characterization of Diamond and 3D-Silicon Pixel Detectors with ATLAS-Pixel Readout Electronics

    CERN Document Server

    Mathes, Markus

    2008-01-01

    Hybrid pixel detectors are used for particle tracking in the innermost layers of current high energy experiments like ATLAS. After the proposed luminosity upgrade of the LHC, they will have to survive very high radiation fluences of up to 10^16 particles per cm^2 per life time. New sensor concepts and materials are required, which promise to be more radiation tolerant than the currently used planar silicon sensors. Most prominent candidates are so-called 3D-silicon and single crystal or poly-crystalline diamond sensors. Using the ATLAS pixel electronics different detector prototypes with a pixel geometry of 400 × 50 um^2 have been built. In particular three devices have been studied in detail: a 3D-silicon and a single crystal diamond detector with an active area of about 1 cm^2 and a poly-crystalline diamond detector of the same size as a current ATLAS pixel detector module (2 × 6 cm^2). To characterize the devices regarding their particle detection efficiency and spatial resolution, the charge collection ...

  5. Development of monolithic pixel detector with SOI technology for the ILC vertex detector

    Science.gov (United States)

    Yamada, M.; Ono, S.; Tsuboyama, T.; Arai, Y.; Haba, J.; Ikegami, Y.; Kurachi, I.; Togawa, M.; Mori, T.; Aoyagi, W.; Endo, S.; Hara, K.; Honda, S.; Sekigawa, D.

    2018-01-01

    We have been developing a monolithic pixel sensor for the International Linear Collider (ILC) vertex detector with the 0.2 μm FD-SOI CMOS process by LAPIS Semiconductor Co., Ltd. We aim to achieve a 3 μm single-point resolution required for the ILC with a 20×20 μm2 pixel. Beam bunch crossing at the ILC occurs every 554 ns in 1-msec-long bunch trains with an interval of 200 ms. Each pixel must record the charge and time stamp of a hit to identify a collision bunch for event reconstruction. Necessary functions include the amplifier, comparator, shift register, analog memory and time stamp implementation in each pixel, and column ADC and Zero-suppression logic on the chip. We tested the first prototype sensor, SOFIST ver.1, with a 120 GeV proton beam at the Fermilab Test Beam Facility in January 2017. SOFIST ver.1 has a charge sensitive amplifier and two analog memories in each pixel, and an 8-bit Wilkinson-type ADC is implemented for each column on the chip. We measured the residual of the hit position to the reconstructed track. The standard deviation of the residual distribution fitted by a Gaussian is better than 3 μm.

  6. Status and future of the ATLAS Pixel Detector at the LHC

    International Nuclear Information System (INIS)

    Rozanov, Alexandre

    2013-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. The detector provides hermetic coverage with three cylindrical layers and three layers of disks in each forward end-cap. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-on-n silicon substrates. Intensive calibration, tuning, timing optimization and monitoring resulted in the successful five years of operation with good detector performance. The record breaking instantaneous luminosities of 7.7×10 33 cm −2 s −1 recently surpassed at the LHC generated a rapidly increasing particle fluence in the ATLAS Pixel Detector. As the radiation dose accumulated, the first effects of radiation damage became observable in the silicon sensors as an increase in the silicon leakage current and the change of the voltage required to fully deplete the sensor. A fourth pixel layer at a radius of 3.3 cm will be added during the long shutdown (2013–2014) together with the replacement of pixel services. A letter of intent was submitted for a completely new Pixel Detector after 2023, capable to take data with extremely high leveled luminosities of 5×10 34 cm −2 s −1 at the high luminosity LHC. -- Highlights: •The ATLAS Pixel Detector provides hermetic coverage with three layers with 80 million pixels. •Calibration, tuning, timing optimization and monitoring resulted in the successful five years of operation with good detector performance. •First effects of radiation damage became observable in the silicon sensors. •A fourth pixel layer at a radius of 3.3 cm will be added during the long shutdown (2013–2014). •Replacement of pixel services in 2013–2014. •A letter of intent was submitted for new Pixel Detector after 2023 for high luminosity LHC

  7. Measurement of 235U Enrichment Using the Semi-Peak-Ratio Technique with CdZnTe Gamma-Ray Detector

    International Nuclear Information System (INIS)

    Ha, J. H.; Ko, W. I.; Lee, S. Y.; Song, D. Y.; Kim, H. D.; Yang, M. S.

    2001-01-01

    In uranium enrichment plants and nuclear fuel fabrication facilities, exact measurement of fissile isotope enrichment of Uranium is required for material accounting in international safeguards inspection as well as process quality control. The purpose of this study was to develop a simple measurement system which can portably be used at nuclear fuel fabrication plants especially dealing with low enriched uranium. For this purpose, a small size CZT (CdZnTe) detector was used, and the detector performance in low uranium gamma/X-rays energy range was investigated by use of various enriched uranium oxide samples. New enrichment measurement technique and analysis method for low enriched uranium oxide, so-called, 'semi-peak ratio technique' was developed. The newly developed method was considered as an alternative technique for the low enrichment and would be useful to account nuclear material in safeguarding activity at nuclear fuel fabrication facility

  8. Radiation Damage Modeling for 3D Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Wallangen, Veronica; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This poster presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS Detector.

  9. Modeling Radiation Damage Effects in 3D Pixel Digitization for the ATLAS Detector

    CERN Document Server

    Giugliarelli, Gilberto; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This poster presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS Detector.

  10. Modeling Radiation Damage Effects in 3D Pixel Digitization for the ATLAS Detector

    CERN Document Server

    Wallangen, Veronica; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of 10$^{15}$ n$_\\mathrm{eq}$/cm$^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This work presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS detector.

  11. Pixel readout ASIC for an APD based 2D X-ray hybrid pixel detector with sub-nanosecond resolution

    Energy Technology Data Exchange (ETDEWEB)

    Thil, Ch., E-mail: christophe.thil@ziti.uni-heidelberg.d [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Baron, A.Q.R. [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Fajardo, P. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France); Fischer, P. [Heidelberg University, Institute of Computer Engineering, B6, 26, 68161 Mannheim (Germany); Graafsma, H. [DESY, Notkestrasse 85, 22607 Hamburg (Germany); Rueffer, R. [ESRF, Polygone Scientifique Louis Neel, 6, rue Jules Horowitz, 38000 Grenoble (France)

    2011-02-01

    The fast response and the short recovery time of avalanche photodiodes (APDs) in linear mode make those devices ideal for direct X-ray detection in applications requiring high time resolution or counting rate. In order to provide position sensitivity, the XNAP project aims at creating a hybrid pixel detector with nanosecond time resolution based on a monolithic APD sensor array with 32 x32 pixels covering about 1 cm{sup 2} active area. The readout is implemented in a pixelated front-end ASIC suited for the readout of such arrays, matched to pixels of 280{mu}mx280{mu}m size. Every single channel features a fast transimpedance amplifier, a discriminator with locally adjustable threshold and two counters with high dynamic range and counting speed able to accumulate X-ray hits with no readout dead time. Additionally, the detector can be operated in list mode by time-stamping every single event with sub-nanosecond resolution. In a first phase of the project, a 4x4 pixel test module is built to validate the conceptual design of the detector. The XNAP project is briefly presented and the performance of the readout ASIC is discussed.

  12. Pixel readout ASIC for an APD based 2D X-ray hybrid pixel detector with sub-nanosecond resolution

    International Nuclear Information System (INIS)

    Thil, Ch.; Baron, A.Q.R.; Fajardo, P.; Fischer, P.; Graafsma, H.; Rueffer, R.

    2011-01-01

    The fast response and the short recovery time of avalanche photodiodes (APDs) in linear mode make those devices ideal for direct X-ray detection in applications requiring high time resolution or counting rate. In order to provide position sensitivity, the XNAP project aims at creating a hybrid pixel detector with nanosecond time resolution based on a monolithic APD sensor array with 32 x32 pixels covering about 1 cm 2 active area. The readout is implemented in a pixelated front-end ASIC suited for the readout of such arrays, matched to pixels of 280μmx280μm size. Every single channel features a fast transimpedance amplifier, a discriminator with locally adjustable threshold and two counters with high dynamic range and counting speed able to accumulate X-ray hits with no readout dead time. Additionally, the detector can be operated in list mode by time-stamping every single event with sub-nanosecond resolution. In a first phase of the project, a 4x4 pixel test module is built to validate the conceptual design of the detector. The XNAP project is briefly presented and the performance of the readout ASIC is discussed.

  13. Small-Scale Readout System Prototype for the STAR PIXEL Detector

    International Nuclear Information System (INIS)

    Szelezniak, Michal; Anderssen, Eric; Greiner, Leo; Matis, Howard; Ritter, Hans Georg; Stezelberger, Thorsten; Sun, Xiangming; Thomas, James; Vu, Chinh; Wieman, Howard

    2008-01-01

    Development and prototyping efforts directed towards construction of a new vertex detector for the STAR experiment at the RHIC accelerator at BNL are presented. This new detector will extend the physics range of STAR by allowing for precision measurements of yields and spectra of particles containing heavy quarks. The innermost central part of the new detector is a high resolution pixel-type detector (PIXEL). PIXEL requirements are discussed as well as a conceptual mechanical design, a sensor development path, and a detector readout architecture. Selected progress with sensor prototypes dedicated to the PIXEL detector is summarized and the approach chosen for the readout system architecture validated in tests of hardware prototypes is discussed

  14. New medical imaging systems exploiting the energy dispersive X-ray diffraction with spectrometric CdZnTe based detector

    International Nuclear Information System (INIS)

    Barbes, Damien

    2016-01-01

    This thesis studies the interest of measuring the coherent scattering of X-rays for breast diagnosis imaging. Nowadays, most of X-ray-based medical imaging techniques use the information of X-rays attenuation through the tissues. It is the case for mammography, the most common breast imaging modality. The recent emergence of energy resolved detectors (based on semiconductors in particular) allows to consider using another phenomenon: the coherent X-ray scattering. Measurement of diffracted spectra can provide new information related to the molecular structure of the examined tissues, in order to improve their characterization and therefore improve the final diagnosis. Two modalities are considered: the breast cancer detection in vivo, following a suspicious mammography result, or biopsy analysis. The coherent scattering measurement system developed during this thesis work uses energy-resolved CdZnTe-based detectors, these detectors combining performances (energy resolution, sensitivity, spatial resolution, and compactness) promising for clinical application. This system is also based on the detector pixelation, which allows to provide an imaging modality capable of characterizing analyzed materials or tissues in one direction without any translation or rotation. A complete study of the measurement system is proposed in this thesis, structured in three main parts: modeling and simulation of the system, development of the processing of the data measured by the detector in order to image and characterize the analyzed sample and finally, designing of a new and more complex experimental setup based on a whole detector and multi-slit collimation system. An experimental validation is proposed for each of these three parts. (author) [fr

  15. Qualification of barrel pixel detector modules for the Phase 1 Upgrade of the CMS vertex detector

    CERN Document Server

    Kudella, Simon

    2016-01-01

    To withstand the higher particle rates of LHC Runs 2 and 3, with expected luminosities of up to $2\\times 10^{34}\\,\\mathrm{cm^{-2}s^{-1}}$, the current CMS pixel detector at the LHC will be replaced as part of the CMS Phase I Upgrade during the extended winter shutdown in 2016/17. The new pixel detector features a new geometry with one additional detector layer in the barrel region~(BPIX) and one pair of additional disks in the forward region~(FPIX), new digital readout chips as well as a new CO$_{2}$-based cooling system for both the barrel and forward region. The BPIX detector module production is summarized, with special focus on the different stages of quality assurance. The quality tests as well as the calibrations which all produced modules undergo in a temperature and humidity controlled environment are described. Exemplarily, the KIT/Aachen production line and its subprocesses are presented together with its quality and yields.

  16. Mechanical design and material budget of the CMS barrel pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Amsler, C; Boesiger, K; Chiochia, V; Maier, R; Meyer, Hp; Robmann, P; Scherr, S; Schmidt, A; Steiner, S [Universitaet Zuerich, Physik-Institut, Winterthurerstr. 190, CH-8057 Zuerich (Switzerland); Erdmann, W; Gabathuler, K; Horisberger, R; Koenig, S; Kotlinski, D; Meier, B; Streuli, S [Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Rizzi, A [ETH Zuerich, Institute for Particle Physics, CH-8093 Zuerich (Switzerland)], E-mail: Alexander.Schmidt@cern.ch

    2009-05-15

    The Compact Muon Solenoid experiment at the Large Hadron Collider at CERN includes a silicon pixel detector as its innermost component. Its main task is the precise reconstruction of charged particles close to the primary interaction vertex. This paper gives an overview of the mechanical requirements and design choices for the barrel pixel detector. The distribution of material in the detector as well as its description in the Monte Carlo simulation are discussed in detail.

  17. Mechanical Design and Material Budget of the CMS Barrel Pixel Detector

    CERN Document Server

    Amsler, C; Chiochia, V; Erdmann, W; Gabathuler, K; Horisberger, R; König, S; Kotlinski, D; Maier, R; Meyer, H; Meier, B; Meyer, Hp; Rizzi, A; Robmann, P; Scherr, S; Schmidt, A; Steiner, S; Erdmann, W; Gabathuler, K; Horisberger, R; König, S; Kotlinski, D; Meier, B; Streuli, S; Rizzi, A

    2009-01-01

    The Compact Muon Solenoid experiment at the Large Hadron Collider at CERN includes a silicon pixel detector as its innermost component. Its main task is the precise reconstruction of charged particles close to the primary interaction vertex. This paper gives an overview of the mechanical requirements and design choices for the barrel pixel detector. The distribution of material in the detector as well as its description in the Monte Carlo simulation are discussed in detail.

  18. Instrumentation effects on U and Pu CBNM standards spectra quality measured on a 500 mm3 CdZnTe and a 2×2 inch LaBr3 detectors

    Science.gov (United States)

    Meleshenkovskii, I.; Borella, A.; Van der Meer, K.; Bruggeman, M.; Pauly, N.; Labeau, P. E.; Schillebeeckx, P.

    2018-01-01

    Nowadays, there is interest in developing gamma-ray measuring devices based on the room temperature operated medium resolution detectors such as semiconductor detectors of the CdZnTe type and scintillators of the LaBr3 type. This is true also for safeguards applications and the International Atomic Energy Agency (IAEA) has launched a project devoted to the assessment of medium resolution gamma-ray spectroscopy for the verification of the isotopic composition of U and Pu bearing samples. This project is carried out within the Non-Destructive Assay Working Group of the European Safeguards Research and Development Association (ESARDA). In this study we analyze medium resolution spectra of U and Pu standards with the aim to develop an isotopic composition determination algorithm, particularly suited for these types of detectors. We show how the peak shape of a CdZnTe detector is influenced by the instrumentation parameters. The experimental setup consisted of a 500 mm3 CdZnTe detector, a 2×2 inch LaBr3 detector, two types of measurement instrumentation - an analogue one and a digital one, and a set of certified samples - a 207Bi point source and U and Pu CBNM standards. The results of our measurements indicate that the lowest contribution to the peak asymmetry and thus the smallest impact on the resolution of the 500 mm3 CdZnTe detector was achieved with the digital MCA. Analysis of acquired spectra allowed to reject poor quality measurement runs and produce summed spectra files with the least impact of instrumentation instabilities. This work is preliminary to further studies concerning the development of an isotopic composition determination algorithm particularly suited for CZT and LaBr3 detectors for safeguards applications.

  19. Performance Studies of Pixel Hybrid Photon Detectors for the LHCb RICH Counters

    CERN Document Server

    Aglieri Rinella, G; Piedigrossi, D; Van Lysebetten, A

    2004-01-01

    The Pixel Hybrid Photon Detector is a vacuum tube with a multi-alkali photo cathode, high voltage cross-focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a readout CMOS electronic chip fully encapsulated in the device. The Pixel HPD fulfils the requirements of the Ring Imaging Cherenkov counters of the LHCb experiment at LHC. The performances of the Pixel HPD will be discussed with reference to laboratory measurements, Cherenkov light imaging in recent beam tests, image distortions due to a magnetic field.

  20. The upgraded Pixel Detector of the ATLAS Experiment for Run 2 at the Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, M., E-mail: malte.backhaus@cern.ch

    2016-09-21

    During Run 1 of the Large Hadron Collider (LHC), the ATLAS Pixel Detector has shown excellent performance. The ATLAS collaboration took advantage of the first long shutdown of the LHC during 2013 and 2014 and extracted the ATLAS Pixel Detector from the experiment, brought it to surface and maintained the services. This included the installation of new service quarter panels, the repair of cables, and the installation of the new Diamond Beam Monitor (DBM). Additionally, a completely new innermost pixel detector layer, the Insertable B-Layer (IBL), was constructed and installed in May 2014 between a new smaller beam pipe and the existing Pixel Detector. With a radius of 3.3 cm the IBL is located extremely close to the interaction point. Therefore, a new readout chip and two new sensor technologies (planar and 3D) are used in the IBL. In order to achieve best possible physics performance the material budget was improved with respect to the existing Pixel Detector. This is realized using lightweight staves for mechanical support and a CO{sub 2} based cooling system. This paper describes the improvements achieved during the maintenance of the existing Pixel Detector as well as the performance of the IBL during the construction and commissioning phase. Additionally, first results obtained during the LHC Run 2 demonstrating the distinguished tracking performance of the new Four Layer ATLAS Pixel Detector are presented.

  1. Synchrotron applications of pixel and strip detectors at Diamond Light Source

    International Nuclear Information System (INIS)

    Marchal, J.; Tartoni, N.; Nave, C.

    2009-01-01

    A wide range of position-sensitive X-ray detectors have been commissioned on the synchrotron X-ray beamlines operating at the Diamond Light Source in UK. In addition to mature technologies such as image-plates, CCD-based detectors, multi-wire and micro-strip gas detectors, more recent detectors based on semiconductor pixel or strip sensors coupled to CMOS read-out chips are also in use for routine synchrotron X-ray diffraction and scattering experiments. The performance of several commercial and developmental pixel/strip detectors for synchrotron studies are discussed with emphasis on the image quality achieved with these devices. Examples of pixel or strip detector applications at Diamond Light Source as well as the status of the commissioning of these detectors on the beamlines are presented. Finally, priorities and ideas for future developments are discussed.

  2. Status of the ATLAS Pixel Detector and its performance after three years of operation

    CERN Document Server

    Favareto, A; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is very important for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. The detector performance is excellent: ~96 % of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, and a good alignment allows high quality track resolution

  3. Status of the ATLAS Pixel Detector and its performance after three years of operation

    CERN Document Server

    Favareto, A; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is very important for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. The detector performance is excellent: ~96% of the pixels are operational, noise occupancy and hit efficiency exceed the design specification, and a good alignment allows high quality track resolution.

  4. X-CSIT: a toolkit for simulating 2D pixel detectors

    Science.gov (United States)

    Joy, A.; Wing, M.; Hauf, S.; Kuster, M.; Rüter, T.

    2015-04-01

    A new, modular toolkit for creating simulations of 2D X-ray pixel detectors, X-CSIT (X-ray Camera SImulation Toolkit), is being developed. The toolkit uses three sequential simulations of detector processes which model photon interactions, electron charge cloud spreading with a high charge density plasma model and common electronic components used in detector readout. In addition, because of the wide variety in pixel detector design, X-CSIT has been designed as a modular platform so that existing functions can be modified or additional functionality added if the specific design of a detector demands it. X-CSIT will be used to create simulations of the detectors at the European XFEL, including three bespoke 2D detectors: the Adaptive Gain Integrating Pixel Detector (AGIPD), Large Pixel Detector (LPD) and DePFET Sensor with Signal Compression (DSSC). These simulations will be used by the detector group at the European XFEL for detector characterisation and calibration. For this purpose, X-CSIT has been integrated into the European XFEL's software framework, Karabo. This will further make it available to users to aid with the planning of experiments and analysis of data. In addition, X-CSIT will be released as a standalone, open source version for other users, collaborations and groups intending to create simulations of their own detectors.

  5. Energy loss and online directional track visualization of fast electrons with the pixel detector Timepix

    Czech Academy of Sciences Publication Activity Database

    Granja, C.; Krist, Pavel; Chvátil, David; Šolc, J.; Pospíšil, S.; Jakubek, J.; Opalka, L.

    2013-01-01

    Roč. 59, DEC (2013), s. 245-261 ISSN 1350-4487 Institutional support: RVO:61389005 Keywords : interaction of radiation with matter * dE/dx detectors * particle tracking detectors * hybrid pixel detectors * active nuclear emulsion * energy loss Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.140, year: 2013

  6. 3D simulations and modeling of new low capacitance silicon pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Bo; Li, Yu Yun [School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105 (China); Center for Semiconductor Particle and photon Imaging Detector Development and Fabrication, Xiangtan University, Xiangtan 411105 (China); Li, Zheng, E-mail: zhengli58@gmail.com [School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105 (China); Center for Semiconductor Particle and photon Imaging Detector Development and Fabrication, Xiangtan University, Xiangtan 411105 (China)

    2016-09-21

    With signal to noise ratio (S/N) being a key parameter of a high performance detector, reducing the detector noise has been one of the main tasks in detector development. A new low capacitance silicon pixel detector is proposed, which is based on a new electrode geometry with reduced effective electrode area while keeping the sensitive volume unchanged. Detector electrical characteristics including electrostatic potential, electric field, full depletion voltage, and capacitance have been simulated in detail using a 3D TCAD tool. From these simulations and calculations, we confirm that the new detector structure has a much reduced capacitance (by a factor of 3) as compared to the traditional pixel detectors with the same sensitive volume. This reduction in detector capacitance can certainly improve the detector signal to noise ratio. However, the full depletion voltage for the new structure is larger than that of the traditional one due to the small electrode effect.

  7. Linearity enhancement design of a 16-channel low-noise front-end readout ASIC for CdZnTe detectors

    International Nuclear Information System (INIS)

    Zeng, Huiming; Wei, Tingcun; Wang, Jia

    2017-01-01

    A 16-channel front-end readout application-specific integrated circuit (ASIC) with linearity enhancement design for cadmium zinc telluride (CdZnTe) detectors is presented in this paper. The resistors in the slow shaper are realized using a high-Z circuit to obtain constant resistance value instead of using only a metal–oxide–semiconductor (MOS) transistor, thus the shaping time of the slow shaper can be kept constant for different amounts of input energies. As a result, the linearity of conversion gain is improved significantly. The ASIC was designed and fabricated in a 0.35 µm CMOS process with a die size of 2.60 mm×3.53 mm. The tested results show that a typical channel provides an equivalent noise charge (ENC) of 109.7e − +16.3e − /pF with a power consumption of 4 mW and achieves a conversion gain of 87 mV/fC with a nonlinearity of <0.4%. The linearity of conversion gain is improved by at least 86.6% as compared with the traditional approaches using the same front-end readout architecture and manufacture process. Moreover, the inconsistency among channels is <0.3%. An energy resolution of 2.975 keV (FWHM) for gamma rays of 59.5 keV was measured by connecting the ASIC to a 5 mm×5 mm ×2 mm CdZnTe detector at room temperature. The front-end readout ASIC presented in this paper achieves an outstanding linearity performance without compromising the noise, power consumption, and chip size performances.

  8. Linearity enhancement design of a 16-channel low-noise front-end readout ASIC for CdZnTe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Huiming; Wei, Tingcun, E-mail: weitc@nwpu.edu.cn; Wang, Jia

    2017-03-01

    A 16-channel front-end readout application-specific integrated circuit (ASIC) with linearity enhancement design for cadmium zinc telluride (CdZnTe) detectors is presented in this paper. The resistors in the slow shaper are realized using a high-Z circuit to obtain constant resistance value instead of using only a metal–oxide–semiconductor (MOS) transistor, thus the shaping time of the slow shaper can be kept constant for different amounts of input energies. As a result, the linearity of conversion gain is improved significantly. The ASIC was designed and fabricated in a 0.35 µm CMOS process with a die size of 2.60 mm×3.53 mm. The tested results show that a typical channel provides an equivalent noise charge (ENC) of 109.7e{sup −}+16.3e{sup −}/pF with a power consumption of 4 mW and achieves a conversion gain of 87 mV/fC with a nonlinearity of <0.4%. The linearity of conversion gain is improved by at least 86.6% as compared with the traditional approaches using the same front-end readout architecture and manufacture process. Moreover, the inconsistency among channels is <0.3%. An energy resolution of 2.975 keV (FWHM) for gamma rays of 59.5 keV was measured by connecting the ASIC to a 5 mm×5 mm ×2 mm CdZnTe detector at room temperature. The front-end readout ASIC presented in this paper achieves an outstanding linearity performance without compromising the noise, power consumption, and chip size performances.

  9. Development of a super B-factory monolithic active pixel detector-the Continuous Acquisition Pixel (CAP) prototypes

    International Nuclear Information System (INIS)

    Varner, G.; Barbero, M.; Bozek, A.; Browder, T.; Fang, F.; Hazumi, M.; Igarashi, A.; Iwaida, S.; Kennedy, J.; Kent, N.; Olsen, S.; Palka, H.; Rosen, M.; Ruckman, L.; Stanic, S.; Trabelsi, K.; Tsuboyama, T.; Uchida, K.

    2005-01-01

    Over the last few years great progress has been made in the technological development of Monolithic Active Pixel Sensors (MAPS) such that upgrades to existing vertex detectors using this technology are now actively being considered. Future vertex detection at an upgraded KEK-B factory, already the highest luminosity collider in the world, will require a detector technology capable of withstanding the increased track densities and larger radiation exposures. Near the beam pipe the current silicon strip detectors have projected occupancies in excess of 100%. Deep sub-micron MAPS look very promising to address this problem. In the context of an upgrade to the Belle vertex detector, the major obstacles to realizing such a device have been concerns about radiation hardness and readout speed. Two prototypes implemented in the TSMC 0.35 μm process have been developed to address these issues. Denoted the Continuous Acquisition Pixel, or CAP, the two variants of this architecture are distinguished in that CAP2 includes an 8-deep sampling pipeline within each 22.5 μm 2 pixel. Preliminary test results and remaining R and D issues are presented

  10. X-ray imaging with photon counting hybrid semiconductor pixel detectors

    CERN Document Server

    Manolopoulos, S; Campbell, M; Snoeys, W; Heijne, Erik H M; Pernigotti, E; Raine, C; Smith, K; Watt, J; O'Shea, V; Ludwig, J; Schwarz, C

    1999-01-01

    Semiconductor pixel detectors, originally developed for particle physics experiments, have been studied as X-ray imaging devices. The performance of devices using the OMEGA 3 read-out chip bump-bonded to pixellated silicon semiconductor detectors is characterised in terms of their signal-to-noise ratio when exposed to 60 kVp X-rays. Although parts of the devices achieve values of this ratio compatible with the noise being photon statistics limited, this is not found to hold for the whole pixel matrix, resulting in the global signal-to-noise ratio being compromised. First results are presented of X-ray images taken with a gallium arsenide pixel detector bump-bonded to a new read-out chip, (MEDIPIX), which is a single photon counting read-out chip incorporating a 15-bit counter in every pixel. (author)

  11. Study of run time errors of the ATLAS Pixel Detector in the 2012 data taking period

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00339072

    2013-05-16

    The high resolution silicon Pixel detector is critical in event vertex reconstruction and in particle track reconstruction in the ATLAS detector. During the pixel data taking operation, some modules (Silicon Pixel sensor +Front End Chip+ Module Control Chip (MCC)) go to an auto-disable state, where the Modules don’t send the data for storage. Modules become operational again after reconfiguration. The source of the problem is not fully understood. One possible source of the problem is traced to the occurrence of single event upset (SEU) in the MCC. Such a module goes to either a Timeout or Busy state. This report is the study of different types and rates of errors occurring in the Pixel data taking operation. Also, the study includes the error rate dependency on Pixel detector geometry.

  12. A silicon pixel detector with routing for external VLSI read-out

    International Nuclear Information System (INIS)

    Thomas, S.L.; Seller, P.

    1988-07-01

    A silicon pixel detector with an array of 32 by 16 hexagonal pixels has been designed and is being built on high resistivity silicon. The detector elements are reverse biased diodes consisting of p-implants in an n-type substrate and are fully depleted from the front to the back of the wafer. They are intended to measure high energy ionising particles traversing the detector. The detailed design of the pixels, their layout and method of read-out are discussed. A number of test structures have been incorporated onto the wafer to enable measurements to be made on individual pixels together with a variety of active devices. The results will give a better understanding of the operation of the pixel array, and will allow testing of computer simulations of more elaborate structures for the future. (author)

  13. The simulation of charge sharing in semiconductor X-ray pixel detectors

    CERN Document Server

    Mathieson, K; O'Shea, V; Passmore, M S; Rahman, M; Smith, K M; Watt, J; Whitehill, C

    2002-01-01

    Two simulation packages were used to model the sharing of charge, due to the scattering and diffusion of carriers, between adjacent pixel elements in semiconductors X-ray detectors. The X-ray interaction and the consequent multiple scattering was modelled with the aid of the Monte Carlo package, MCNP. The resultant deposited charge distribution was then used to create the charge cloud profile in the finite element semiconductor simulation code MEDICI. The analysis of the current pulses induced on pixel electrodes for varying photon energies was performed for a GaAs pixel detector. For a pixel pitch of 25 mu m, the charge lost to a neighbouring pixel was observed to be constant, at 0.6%, through the energies simulated. Ultimately, a fundamental limit on the pixel element size for imaging and spectroscopic devices may be set due to these key physical principles.

  14. The Upgraded Pixel Detector of the ATLAS Experiment for Run-2 at the LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00084948; The ATLAS collaboration

    2016-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. The new detector, built to cope with high radiation and expected occupancy, is the first large scale application of 3D detectors and CMOS 130 nm technology. In addition the Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning and performance of the 4-layer Pixel Detector, in particular the IBL, will be presented using collision data.

  15. The Upgraded Pixel Detector of the ATLAS Experiment for Run-2

    CERN Document Server

    Ferrere, Didier; The ATLAS collaboration

    2016-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. The new detector, built to cope with high radiation and expected occupancy, is the first large scale application of 3D detectors and CMOS 130nm technology. In addition the Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning and performance of the 4-layer Pixel Detector, in particular the IBL, will be presented, using collision data.

  16. The upgraded Pixel Detector of the ATLAS experiment for Run-2 at the Large Hadron Collider

    CERN Document Server

    Giordani, MarioPaolo; The ATLAS collaboration

    2016-01-01

    Run-2 of the LHC is providing new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. The new detector, built to cope with high radiation and expected occupancy, is the first large scale application of 3D detectors and CMOS 130nm technology. In addition the Pixel detector was refurbished with a new service quarter panel to recover about 3% of defective modules lost during run-1 and a new optical readout system to readout the data at higher speed while reducing the occupancy when running with increased luminosity. The commissioning and performance of the 4-layer Pixel Detector, in particular the IBL, will be presented, using collision data.

  17. Defective pixel map creation based on wavelet analysis in digital radiography detectors

    International Nuclear Information System (INIS)

    Park, Chun Joo; Lee, Hyoung Koo; Song, William Y.; Achterkirchen, Thorsten Graeve; Kim, Ho Kyung

    2011-01-01

    The application of digital radiography detectors has attracted increasing attention in both medicine and industry. Since the imaging detectors are fabricated by semiconductor manufacturing process over large areas, defective pixels in the detectors are unavoidable. Moreover, the radiation damage due to the routine use of the detectors progressively increases the density of defective pixels. In this study, we present a method of identifying defective pixels in digital radiography detectors based on wavelet analysis. Artifacts generated due to wavelet transformations have been prevented by an additional local threshold method. The proposed method was applied to a sample digital radiography and the result was promising. The proposed method uses a single pair of dark and white images and does not require them to be corrected in gain-and-offset properties. This method will be helpful for the reliable use of digital radiography detectors through the working lifetime.

  18. Design of readout drivers for ATLAS pixel detectors using field programmable gate arrays

    CERN Document Server

    Sivasubramaniyan, Sriram

    Microstrip detectors are an integral patt of high energy physics research . Special protocols are used to transmit the data from these detectors . To readout the data from such detectors specialized instrumentation have to be designed . To achieve this task, creative and innovative high speed algorithms were designed simulated and implemented in Field Programmable gate arrays, using CAD/CAE tools. The simulation results indicated that these algorithms would be able to perform all the required tasks quickly and efficiently. This thesis describes the design of data acquisition system called the Readout Drivers (ROD) . It focuses on the ROD data path for ATLAS Pixel detectors. The data path will be an integrated part of Readout Drivers setup to decode the data from the silicon micro strip detectors and pixel detectors. This research also includes the design of Readout Driver controller. This Module is used to control the operation of the ROD. This module is responsible for the operation of the Pixel decoders bas...

  19. Optimization of CZT Detectors with Sub-mm Pixel Pitches Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop and optimize 0.5 cm thick Cadmium Zinc Telluride (CZT) detectors with very small pixel pitches, i.e. 350 micron and 600 micron. The proposed...

  20. Performance and operation experience of the Atlas Semiconductor Tracker and Pixel Detector at the LHC.

    CERN Document Server

    Stanecka, E; The ATLAS collaboration

    2013-01-01

    After more than 3 years of successful operation at the LHC, we report on the operation and performance of the ATLAS Pixel Detector and Semi-Conductor Tracker (SCT) functioning in a high luminosity, high radiation environment.

  1. Pixel Detector Developments for Tracker Upgrades of the High Luminosity LHC

    CERN Document Server

    Meschini, Marco; Dalla Betta, G. F; Dinardo, Mauro; Giacomini, G; Menasce, Dario; Mendicino, R; Messineo, Alberto; Moroni, Luigi; Ronchin, S; Sultan, D.M.S; Uplegger, Lorenzo; Viliani, Lorenzo; Zoi, Irene; Zuolo, Davide

    2017-01-01

    and 3D devices. The results on the 3D pixel sensors before irradiation are very satisfactory and % make us confident support the conclusion that columnar devices are % 3D devices very good candidates for the inner layers of the upgrade pixel detectors.

  2. Studies of Inner Detector Layouts with 5 Pixel layers for the Phase-II Upgrade

    CERN Document Server

    Ludwig, A; The ATLAS collaboration; Garcia-Sciveres, M

    2013-01-01

    This note describes a study of Inner Detector layouts for the phase-II upgrade. Starting from the LOI layout the impact of adding a 5th pixel layer, and shortening the pixel and/or SCT barrel layers is studied.

  3. Limits in point to point resolution of MOS based pixels detector arrays

    Science.gov (United States)

    Fourches, N.; Desforge, D.; Kebbiri, M.; Kumar, V.; Serruys, Y.; Gutierrez, G.; Leprêtre, F.; Jomard, F.

    2018-01-01

    In high energy physics point-to-point resolution is a key prerequisite for particle detector pixel arrays. Current and future experiments require the development of inner-detectors able to resolve the tracks of particles down to the micron range. Present-day technologies, although not fully implemented in actual detectors, can reach a 5-μm limit, this limit being based on statistical measurements, with a pixel-pitch in the 10 μm range. This paper is devoted to the evaluation of the building blocks for use in pixel arrays enabling accurate tracking of charged particles. Basing us on simulations we will make here a quantitative evaluation of the physical and technological limits in pixel size. Attempts to design small pixels based on SOI technology will be briefly recalled here. A design based on CMOS compatible technologies that allow a reduction of the pixel size below the micrometer is introduced here. Its physical principle relies on a buried carrier-localizing collecting gate. The fabrication process needed by this pixel design can be based on existing process steps used in silicon microelectronics. The pixel characteristics will be discussed as well as the design of pixel arrays. The existing bottlenecks and how to overcome them will be discussed in the light of recent ion implantation and material characterization experiments.

  4. 3D track reconstruction capability of a silicon hybrid active pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, Benedikt; Pichotka, Martin; Pospisil, Stanislav; Vycpalek, Jiri [Czech Technical University in Prague, Institute of Experimental and Applied Physics, Praha (Czech Republic); Burian, Petr; Broulim, Pavel [Czech Technical University in Prague, Institute of Experimental and Applied Physics, Praha (Czech Republic); University of West Bohemia, Faculty of Electrical Engineering, Pilsen (Czech Republic); Jakubek, Jan [Advacam s.r.o., Praha (Czech Republic)

    2017-06-15

    Timepix3 detectors are the latest generation of hybrid active pixel detectors of the Medipix/Timepix family. Such detectors consist of an active sensor layer which is connected to the readout ASIC (application specific integrated circuit), segmenting the detector into a square matrix of 256 x 256 pixels (pixel pitch 55 μm). Particles interacting in the active sensor material create charge carriers, which drift towards the pixelated electrode, where they are collected. In each pixel, the time of the interaction (time resolution 1.56 ns) and the amount of created charge carriers are measured. Such a device was employed in an experiment in a 120 GeV/c pion beam. It is demonstrated, how the drift time information can be used for ''4D'' particle tracking, with the three spatial dimensions and the energy losses along the particle trajectory (dE/dx). Since the coordinates in the detector plane are given by the pixelation (x,y), the x- and y-resolution is determined by the pixel pitch (55 μm). A z-resolution of 50.4 μm could be achieved (for a 500 μm thick silicon sensor at 130 V bias), whereby the drift time model independent z-resolution was found to be 28.5 μm. (orig.)

  5. 3D track reconstruction capability of a silicon hybrid active pixel detector

    Science.gov (United States)

    Bergmann, Benedikt; Pichotka, Martin; Pospisil, Stanislav; Vycpalek, Jiri; Burian, Petr; Broulim, Pavel; Jakubek, Jan

    2017-06-01

    Timepix3 detectors are the latest generation of hybrid active pixel detectors of the Medipix/Timepix family. Such detectors consist of an active sensor layer which is connected to the readout ASIC (application specific integrated circuit), segmenting the detector into a square matrix of 256 × 256 pixels (pixel pitch 55 μm). Particles interacting in the active sensor material create charge carriers, which drift towards the pixelated electrode, where they are collected. In each pixel, the time of the interaction (time resolution 1.56 ns) and the amount of created charge carriers are measured. Such a device was employed in an experiment in a 120 GeV/c pion beam. It is demonstrated, how the drift time information can be used for "4D" particle tracking, with the three spatial dimensions and the energy losses along the particle trajectory (dE/dx). Since the coordinates in the detector plane are given by the pixelation ( x, y), the x- and y-resolution is determined by the pixel pitch (55 μm). A z-resolution of 50.4 μm could be achieved (for a 500 μm thick silicon sensor at 130 V bias), whereby the drift time model independent z-resolution was found to be 28.5 μm.

  6. A pixel detector for the protein crystallography beamline at the SLS

    CERN Document Server

    Brönnimann, C; Eikenberry, E F; Fischer, P; Florin, S; Horisberger, R P; Lindner, Manfred; Schmitt, B; Schulze, C

    2002-01-01

    At the Paul Scherrer Institute a new synchrotron light source is currently under construction, the Swiss Light Source (SLS), which will be operational in summer 2001. Among the first beamlines is a high brightness, micro-focusing protein crystallography beamline. It will be equipped with a pixel detector, which has several features of interest for the next generation of protein crystallography detectors. The point spread function and the effect of charge sharing was measured with a prototype detector in a test experiment at the European Synchrotron Radiation Facility in Grenoble. The concepts of the SLS pixel detector is presented as well as test results from radiation hard prototype chips.

  7. Digital column readout architectures for hybrid pixel detector readout chips

    International Nuclear Information System (INIS)

    Poikela, T; Plosila, J; Westerlund, T; Buytaert, J; Campbell, M; Gaspari, M De; Llopart, X; Wyllie, K; Gromov, V; Kluit, R; Beuzekom, M van; Zappon, F; Zivkovic, V; Brezina, C; Desch, K; Fu, Y; Kruth, A

    2014-01-01

    In this paper, two digital column architectures suitable for sparse readout of data from a pixel matrix in trigger-less applications are presented. Each architecture reads out a pixel matrix of 256 x 256 pixels with a pixel pitch of 55 μm. The first architecture has been implemented in the Timepix3 chip, and this is presented together with initial measurements. Simulation results and measured data are compared. The second architecture has been designed for Velopix, a readout chip planned for the LHCb VELO upgrade. Unlike Timepix3, this has to be tolerant to radiation-induced single-event effects. Results from post-layout simulations are shown with the circuit architectures

  8. Development of a High Dynamic Range Pixel Array Detector for Synchrotrons and XFELs

    Science.gov (United States)

    Weiss, Joel Todd

    Advances in synchrotron radiation light source technology have opened new lines of inquiry in material science, biology, and everything in between. However, x-ray detector capabilities must advance in concert with light source technology to fully realize experimental possibilities. X-ray free electron lasers (XFELs) place particularly large demands on the capabilities of detectors, and developments towards diffraction-limited storage ring sources also necessitate detectors capable of measuring very high flux [1-3]. The detector described herein builds on the Mixed Mode Pixel Array Detector (MM-PAD) framework, developed previously by our group to perform high dynamic range imaging, and the Adaptive Gain Integrating Pixel Detector (AGIPD) developed for the European XFEL by a collaboration between Deustsches Elektronen-Synchrotron (DESY), the Paul-Scherrer-Institute (PSI), the University of Hamburg, and the University of Bonn, led by Heinz Graafsma [4, 5]. The feasibility of combining adaptive gain with charge removal techniques to increase dynamic range in XFEL experiments is assessed by simulating XFEL scatter with a pulsed infrared laser. The strategy is incorporated into pixel prototypes which are evaluated with direct current injection to simulate very high incident x-ray flux. A fully functional 16x16 pixel hybrid integrating x-ray detector featuring several different pixel architectures based on the prototypes was developed. This dissertation describes its operation and characterization. To extend dynamic range, charge is removed from the integration node of the front-end amplifier without interrupting integration. The number of times this process occurs is recorded by a digital counter in the pixel. The parameter limiting full well is thereby shifted from the size of an integration capacitor to the depth of a digital counter. The result is similar to that achieved by counting pixel array detectors, but the integrators presented here are designed to tolerate a

  9. Investigation of photon counting pixel detectors for X-ray spectroscopy and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Talla, Patrick Takoukam

    2011-04-07

    The Medipix2 and Medipix3 detectors are hybrid pixelated photon counting detectors with a pixel pitch of 55 {mu}m. The sensor material used in this thesis was silicon. Because of their small pixel size they suffer from charge sharing i.e. an incoming photon can be registered by more than one pixel. In order to correct for charge sharing due to lateral diffusion of charge carriers, the Medipix3 detector was developed: with its Charge Summing Mode, the charge collected in a cluster of 2 x 2 pixel is added up and attributed to only one pixel whose counter is incremented. The adjustable threshold of the detectors allows to count the photons and to gain information on their energy. The main purposes of the thesis are to investigate spectral and imaging properties of pixelated photon counting detectors from the Medipix family such as Medipix2 and Medipix3. The investigations are based on simulations and measurements. In order to investigate the spectral properties of the detectors measurements were performed using fluorescence lines of materials such as molybdenum, silver but also some radioactive sources such as Am-241 or Cd-109. From the measured data, parameters like the threshold dispersion and the gain variation from pixel-to-pixel were extracted and used as input in the Monte Carlo code ROSI to model the responses of the detector to monoenergetic photons. The measured data are well described by the simulations for Medipix2 and for Medipix3 operating in Charge Summing Mode. Due to charge sharing and due to the energy dependence of attenuation processes in silicon and to Compton scattering the incoming and the measured spectrum differ substantially from each other. Since the responses to monoenergetic photons are known, a deconvolution was performed to determine the true incoming spectrum. Several direct and iterative methods were successfully applied on measured and simulated data of an X-ray tube and radioactive sources. The knowledge of the X-ray spectrum is

  10. Investigation of photon counting pixel detectors for X-ray spectroscopy and imaging

    International Nuclear Information System (INIS)

    Talla, Patrick Takoukam

    2011-01-01

    The Medipix2 and Medipix3 detectors are hybrid pixelated photon counting detectors with a pixel pitch of 55 μm. The sensor material used in this thesis was silicon. Because of their small pixel size they suffer from charge sharing i.e. an incoming photon can be registered by more than one pixel. In order to correct for charge sharing due to lateral diffusion of charge carriers, the Medipix3 detector was developed: with its Charge Summing Mode, the charge collected in a cluster of 2 x 2 pixel is added up and attributed to only one pixel whose counter is incremented. The adjustable threshold of the detectors allows to count the photons and to gain information on their energy. The main purposes of the thesis are to investigate spectral and imaging properties of pixelated photon counting detectors from the Medipix family such as Medipix2 and Medipix3. The investigations are based on simulations and measurements. In order to investigate the spectral properties of the detectors measurements were performed using fluorescence lines of materials such as molybdenum, silver but also some radioactive sources such as Am-241 or Cd-109. From the measured data, parameters like the threshold dispersion and the gain variation from pixel-to-pixel were extracted and used as input in the Monte Carlo code ROSI to model the responses of the detector to monoenergetic photons. The measured data are well described by the simulations for Medipix2 and for Medipix3 operating in Charge Summing Mode. Due to charge sharing and due to the energy dependence of attenuation processes in silicon and to Compton scattering the incoming and the measured spectrum differ substantially from each other. Since the responses to monoenergetic photons are known, a deconvolution was performed to determine the true incoming spectrum. Several direct and iterative methods were successfully applied on measured and simulated data of an X-ray tube and radioactive sources. The knowledge of the X-ray spectrum is

  11. Study of CdTe:Cl and CdZnTe detectors for medical multi-slices X-ray Computed Tomography; Etude de detecteurs en CdTe:Cl et CdZnTe pour la tomographie X medicale multicoupes

    Energy Technology Data Exchange (ETDEWEB)

    Ricq, St

    1999-09-28

    The application of CdTe and CdZnTe detectors to medical X-ray Computed Tomography have been investigated. Different electrodes (Au, Pt, In) have been deposited on CdZnTe HPBM and on CdTe:ClTHM. Their injection properties have been determined with Current-Voltage characteristics. Under X-ray in CT conditions, injection currents measurements reveal trapped carriers space-charges formation. The same way, the comparisons of the responses to X-beam cut-off with various injection possibilities enable to follow the space-charges evolutions and then to determine the predominant traps types. Nevertheless, both hole and electron traps are responsible for the memory effect e.g. the currents levels dependence with irradiation history. This effect is noticed in particular on responses to fast flux variations that simulate scanner's conditions. Trap levels probably corresponding to native defects are responsible for these limitations. In order to make such detectors suitable for X-ray Computed Tomography, significant progresses in CdTe for CdZnTe crystal growth with an important defects densities reduction (factor 10), or possibly counting mode operation, seem necessary. (author)

  12. Study of CdTe:Cl and CdZnTe detectors for medical multi-slices X-ray Computed Tomography; Etude de detecteurs en CdTe:Cl et CdZnTe pour la tomographie X medicale multicoupes

    Energy Technology Data Exchange (ETDEWEB)

    Ricq, St

    1999-09-28

    The application of CdTe and CdZnTe detectors to medical X-ray Computed Tomography have been investigated. Different electrodes (Au, Pt, In) have been deposited on CdZnTe HPBM and on CdTe:ClTHM. Their injection properties have been determined with Current-Voltage characteristics. Under X-ray in CT conditions, injection currents measurements reveal trapped carriers space-charges formation. The same way, the comparisons of the responses to X-beam cut-off with various injection possibilities enable to follow the space-charges evolutions and then to determine the predominant traps types. Nevertheless, both hole and electron traps are responsible for the memory effect e.g. the currents levels dependence with irradiation history. This effect is noticed in particular on responses to fast flux variations that simulate scanner's conditions. Trap levels probably corresponding to native defects are responsible for these limitations. In order to make such detectors suitable for X-ray Computed Tomography, significant progresses in CdTe for CdZnTe crystal growth with an important defects densities reduction (factor 10), or possibly counting mode operation, seem necessary. (author)

  13. Modelling of the small pixel effect in gallium arsenide X-ray imaging detectors

    CERN Document Server

    Sellin, P J

    1999-01-01

    A Monte Carlo simulation has been carried out to investigate the small pixel effect in highly pixellated X-ray imaging detectors fabricated from semi-insulating gallium arsenide. The presence of highly non-uniform weighting fields in detectors with a small pixel geometry causes the majority of the induced signal to be generated when the moving charges are close to the pixellated contacts. The response of GaAs X-ray imaging detectors is further complicated by the presence of charge trapping, particularly of electrons. In this work detectors are modelled with a pixel pitch of 40 and 150 mu m, and with thicknesses of 300 and 500 mu m. Pulses induced in devices with 40 mu m pixels are due almost totally to the movement of the lightly-trapped holes and can exhibit significantly higher charge collection efficiencies than detectors with large electrodes, in which electron trapping is significant. Details of the charge collection efficiencies as a function of interaction depth in the detector and of the incident phot...

  14. Optimization of detector pixel size for stent visualization in x-ray fluoroscopy

    International Nuclear Information System (INIS)

    Jiang Yuhao; Wilson, David L.

    2006-01-01

    Pixel size is of great interest in the flat-panel detector design because of its potential impact on image quality. In the particular case of angiographic x-ray fluoroscopy, small pixels are required in order to adequately visualize interventional devices such as guidewires and stents which have wire diameters as small as 200 and 50 μm, respectively. We used quantitative experimental and modeling techniques to investigate the optimal pixel size for imaging stents. Image quality was evaluated by the ability of subjects to perform two tasks: detect the presence of a stent and discriminate a partially deployed stent from a fully deployed one in synthetic images. With measurements at 50, 100, 200, and 300 μm, the 100 μm pixel size gave the maximum contrast sensitivity for the detection experiment with the idealized direct detector. For an idealized indirect detector with a scintillating layer, an optimal pixel size was obtained at 200 μm pixel size. A channelized human observer model predicted a peak at 150 and 170 μm, for the idealized direct and indirect detectors, respectively. With regard to the stent deployment task for both detector types, smaller pixel sizes are favored and there is a steep drop in performance with larger pixels. In general, with the increasing exposures, the model and measurements give the enhanced contrast sensitivities and a smaller optimal pixel size. The effects of electronic noise and fill factor were investigated using the model. We believe that the experimental results and human observer model predications can help guide the flat-panel detector design. In addition, the human observer model should work on the similar images and be applicable to the future model and actual flat-panel implementations

  15. A review of advances in pixel detectors for experiments with high rate and radiation

    Science.gov (United States)

    Garcia-Sciveres, Maurice; Wermes, Norbert

    2018-06-01

    The large Hadron collider (LHC) experiments ATLAS and CMS have established hybrid pixel detectors as the instrument of choice for particle tracking and vertexing in high rate and radiation environments, as they operate close to the LHC interaction points. With the high luminosity-LHC upgrade now in sight, for which the tracking detectors will be completely replaced, new generations of pixel detectors are being devised. They have to address enormous challenges in terms of data throughput and radiation levels, ionizing and non-ionizing, that harm the sensing and readout parts of pixel detectors alike. Advances in microelectronics and microprocessing technologies now enable large scale detector designs with unprecedented performance in measurement precision (space and time), radiation hard sensors and readout chips, hybridization techniques, lightweight supports, and fully monolithic approaches to meet these challenges. This paper reviews the world-wide effort on these developments.

  16. Radiationhard components for the control system of a future ATLAS pixel detector

    International Nuclear Information System (INIS)

    Becker, K; Boek, J; Kersten, S; Kind, P; Maettig, P; Puellen, L; Zeitnitz, C

    2011-01-01

    The upgrade of the ATLAS experiment for the High Luminosity LHC (HL-LHC) will include a new pixel detector. A completely new detector control system (DCS) for this pixel detector will be required in order to cope with the substantial increase in radiation at the HL-LHC. The DCS has to have a very high reliability and all components installed within the detector volume have to be radiationhard. This will ensure a safe operation of the pixel detector and the experiment. A further design constraint is the minimization of the used material and cables in order to limit the impact on the tracking performance to a minimum. To meet these requirements we propose a DCS network which consists of a DCS chip and a DCS controller. In the following we present the development of the first prototypes for the DCS chip and the DCS controller with a special focus on the communication interface, radiation hardness and robustness against single event upsets.

  17. Optical readout in a multi-module system test for the ATLAS pixel detector

    International Nuclear Information System (INIS)

    Flick, Tobias; Becks, Karl-Heinz; Gerlach, Peter; Kersten, Susanne; Maettig, Peter; Nderitu Kirichu, Simon; Reeves, Kendall; Richter, Jennifer; Schultes, Joachim

    2006-01-01

    The innermost part of the ATLAS experiment at the LHC, CERN, will be a pixel detector, which is presently under construction. The command messages and the readout data of the detector are transmitted over an optical data path. The readout chain consists of many components which are produced at several locations around the world, and must work together in the pixel detector. To verify that these parts are working together as expected a system test has been built up. It consists of detector modules, optoboards, optical fibres, Back of Crate cards, Readout Drivers, and control computers. In this paper, the system test setup and the operation of the readout chain are described. Also, some results of tests using the final pixel detector readout chain are given

  18. Iterative local Chi2 alignment algorithm for the ATLAS Pixel detector

    CERN Document Server

    Göttfert, Tobias

    The existing local chi2 alignment approach for the ATLAS SCT detector was extended to the alignment of the ATLAS Pixel detector. This approach is linear, aligns modules separately, and uses distance of closest approach residuals and iterations. The derivation and underlying concepts of the approach are presented. To show the feasibility of the approach for Pixel modules, a simplified, stand-alone track simulation, together with the alignment algorithm, was developed with the ROOT analysis software package. The Pixel alignment software was integrated into Athena, the ATLAS software framework. First results and the achievable accuracy for this approach with a simulated dataset are presented.

  19. Drift time variations in CdZnTe detectors measured with alpha-particles: Their correlation with the detector’s responses

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov A. E.; Butcher, J.; Hamade, M.; Petryk, M.; Bolotnikov, A.; Camarda, G.; Cui, Y.; Hossain, A.; Kim, K.; Yang, G.; and James, R.

    2012-05-14

    Homogeneity of properties related to material crystallinity is a critical parameter for achieving high-performance CdZnTe (CZT) radiation detectors. Unfortunately, this requirement is not always satisfied in today's commercial CZT material due to high concentrations of extended defects, in particular subgrain boundaries, which are believed to be part of the causes hampering the energy resolution and efficiency of CZT detectors. In the past, the effects of subgrain boundaries have been studied in Si, Ge and other semiconductors. It was demonstrated that subgrain boundaries tend to accumulate secondary phases and impurities causing inhomogeneous distributions of trapping centers. It was also demonstrated that subgrain boundaries result in local perturbations of the electric field, which affect the carrier transport and other properties of semiconductor devices. The subgrain boundaries in CZT material likely behave in a similar way, which makes them responsible for variations in the electron drift time and carrier trapping in CZT detectors. In this work, we employed the transient current technique to measure variations in the electron drift time and related the variations to the device performances and subgrain boundaries, whose presence in the crystals were confirmed with white beam X-ray diffraction topography and infrared transmission microscopy.

  20. New pixelized Micromegas detector with low discharge rate for the COMPASS experiment

    CERN Document Server

    Neyret, D.; Anfreville, M.; Bedfer, Y.; Burtin, E.; Coquelet, C.; d'Hose, N.; Desforge, D.; Giganon, A.; Jourde, D.; Kunne, F.; Magnon, A.; Makke, N.; Marchand, C.; Paul, B.; Platchkov, S.; Thibaud, F.; Usseglio, M.; Vandenbroucke, M.

    2012-01-01

    New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm^{2}, 10 times larger than for the present Micromegas detectors) with pixelized read-out in the central part, light and integrated electronics, and improved robustness. Two solutions of reduction of discharge impact have been studied, with Micromegas detectors using resistive layers and using an additional GEM foil. Performance of such detectors has also been measured. A large size prototypes with nominal active area and pixelized read-out has been produced and installed at COMPASS in 2010. In 2011 prototypes featuring an additional GEM foil, as well as an resistive prototype, are installed at COMPASS and preliminary results from those detectors presented very go...

  1. Neural network based cluster creation in the ATLAS silicon Pixel Detector

    CERN Document Server

    Andreazza, A; The ATLAS collaboration

    2013-01-01

    The read-out from individual pixels on planar semi-conductor sensors are grouped into clusters to reconstruct the location where a charged particle passed through the sensor. The resolution given by individual pixel sizes is significantly improved by using the information from the charge sharing between pixels. Such analog cluster creation techniques have been used by the ATLAS experiment for many years to obtain an excellent performance. However, in dense environments, such as those inside high-energy jets, clusters have an increased probability of merging the charge deposited by multiple particles. Recently, a neural network based algorithm which estimates both the cluster position and whether a cluster should be split has been developed for the ATLAS Pixel Detector. The algorithm significantly reduces ambiguities in the assignment of pixel detector measurement to tracks within jets and improves the position accuracy with respect to standard interpolation techniques by taking into account the 2-dimensional ...

  2. Neural network based cluster creation in the ATLAS silicon pixel detector

    CERN Document Server

    Selbach, K E; The ATLAS collaboration

    2012-01-01

    The read-out from individual pixels on planar semi-conductor sensors are grouped into clusters to reconstruct the location where a charged particle passed through the sensor. The resolution given by individual pixel sizes is significantly improved by using the information from the charge sharing between pixels. Such analog cluster creation techniques have been used by the ATLAS experiment for many years to obtain an excellent performance. However, in dense environments, such as those inside high-energy jets, clusters have an increased probability of merging the charge deposited by multiple particles. Recently, a neural network based algorithm which estimates both the cluster position and whether a cluster should be split has been developed for the ATLAS pixel detector. The algorithm significantly reduces ambiguities in the assignment of pixel detector measurement to tracks within jets and improves the position accuracy with respect to standard interpolation techniques by taking into account the 2-dimensional ...

  3. Performance of hybrid photon detector prototypes with encapsulated silicon pixel detector and readout for the RICH counters of LHCb

    International Nuclear Information System (INIS)

    Campbell, M.; George, K.A.; Girone, M.; Gys, T.; Jolly, S.; Piedigrossi, D.; Riedler, P.; Rozema, P.; Snoeys, W.; Wyllie, K.

    2003-01-01

    These proceedings report on the performance of the latest prototype pixel hybrid photon detector in preparation for the LHCb Ring Imaging Cherenkov detectors. The prototype encapsulates a silicon pixel detector bump-bonded to a binary read-out chip with short (25 ns) peaking time and low ( - ) detection threshold. A brief description of the prototype is given, followed by the preliminary results of the characterisation of the prototype behaviour when tested using a low intensity pulsed light emitting diode. The results obtained are in good agreement with those obtained using previous prototypes. The proceedings conclude with a summary of the current status and future plans

  4. Edge pixel response studies of edgeless silicon sensor technology for pixellated imaging detectors

    Science.gov (United States)

    Maneuski, D.; Bates, R.; Blue, A.; Buttar, C.; Doonan, K.; Eklund, L.; Gimenez, E. N.; Hynds, D.; Kachkanov, S.; Kalliopuska, J.; McMullen, T.; O'Shea, V.; Tartoni, N.; Plackett, R.; Vahanen, S.; Wraight, K.

    2015-03-01

    Silicon sensor technologies with reduced dead area at the sensor's perimeter are under development at a number of institutes. Several fabrication methods for sensors which are sensitive close to the physical edge of the device are under investigation utilising techniques such as active-edges, passivated edges and current-terminating rings. Such technologies offer the goal of a seamlessly tiled detection surface with minimum dead space between the individual modules. In order to quantify the performance of different geometries and different bulk and implant types, characterisation of several sensors fabricated using active-edge technology were performed at the B16 beam line of the Diamond Light Source. The sensors were fabricated by VTT and bump-bonded to Timepix ROICs. They were 100 and 200 μ m thick sensors, with the last pixel-to-edge distance of either 50 or 100 μ m. The sensors were fabricated as either n-on-n or n-on-p type devices. Using 15 keV monochromatic X-rays with a beam spot of 2.5 μ m, the performance at the outer edge and corners pixels of the sensors was evaluated at three bias voltages. The results indicate a significant change in the charge collection properties between the edge and 5th (up to 275 μ m) from edge pixel for the 200 μ m thick n-on-n sensor. The edge pixel performance of the 100 μ m thick n-on-p sensors is affected only for the last two pixels (up to 110 μ m) subject to biasing conditions. Imaging characteristics of all sensor types investigated are stable over time and the non-uniformities can be minimised by flat-field corrections. The results from the synchrotron tests combined with lab measurements are presented along with an explanation of the observed effects.

  5. Module Production and Qualification for the Phase I Upgrade of the CMS Pixel Detector

    CERN Document Server

    AUTHOR|(CDS)2086689

    2015-01-01

    After consolidation of the LHC in 2013/14 its centre-of-mass energy will increase to 13TeV and the luminosity will reach $2 \\cdot 10^{34}\\, \\textnormal{cm}^{-2} \\textnormal{s}^{-1}$, which is twice the design luminosity. The latter will result in more simultaneous particle collisions, which would significantly increase the dead time of the current readout chip of the CMS pixel detector. Therefore the entire CMS pixel detector is replaced in 2016/17 and a new digital readout with larger buffers will be used to handle increasing pixel hit rates. An additional fourth barrel-layer provides more space points to improve track reconstruction. Half of the required modules for layer four is being produced at Karlsruhe Institute of Technology (KIT). This poster deals with the smallest discrete subunit of the pixel detector, the module and its assembly process. Moreover first production experience will be shown.

  6. Tracking performance of a single-crystal and a polycrystalline diamond pixel-detector

    Energy Technology Data Exchange (ETDEWEB)

    Menasce, D.; et al.

    2013-06-01

    We present a comparative characterization of the performance of a single-crystal and a polycrystalline diamond pixel-detector employing the standard CMS pixel readout chips. Measurements were carried out at the Fermilab Test Beam Facility, FTBF, using protons of momentum 120 GeV/c tracked by a high-resolution pixel telescope. Particular attention was directed to the study of the charge-collection, the charge-sharing among adjacent pixels and the achievable position resolution. The performance of the single-crystal detector was excellent and comparable to the best available silicon pixel-detectors. The measured average detection-efficiency was near unity, ε = 0.99860±0.00006, and the position-resolution for shared hits was about 6 μm. On the other hand, the performance of the polycrystalline detector was hampered by its lower charge collection distance and the readout chip threshold. A new readout chip, capable of operating at much lower threshold (around 1 ke$-$), would be required to fully exploit the potential performance of the polycrystalline diamond pixel-detector.

  7. High-speed X-ray imaging pixel array detector for synchrotron bunch isolation.

    Science.gov (United States)

    Philipp, Hugh T; Tate, Mark W; Purohit, Prafull; Shanks, Katherine S; Weiss, Joel T; Gruner, Sol M

    2016-03-01

    A wide-dynamic-range imaging X-ray detector designed for recording successive frames at rates up to 10 MHz is described. X-ray imaging with frame rates of up to 6.5 MHz have been experimentally verified. The pixel design allows for up to 8-12 frames to be stored internally at high speed before readout, which occurs at a 1 kHz frame rate. An additional mode of operation allows the integration capacitors to be re-addressed repeatedly before readout which can enhance the signal-to-noise ratio of cyclical processes. This detector, along with modern storage ring sources which provide short (10-100 ps) and intense X-ray pulses at megahertz rates, opens new avenues for the study of rapid structural changes in materials. The detector consists of hybridized modules, each of which is comprised of a 500 µm-thick silicon X-ray sensor solder bump-bonded, pixel by pixel, to an application-specific integrated circuit. The format of each module is 128 × 128 pixels with a pixel pitch of 150 µm. In the prototype detector described here, the three-side buttable modules are tiled in a 3 × 2 array with a full format of 256 × 384 pixels. The characteristics, operation, testing and application of the detector are detailed.

  8. The Dosepix detector—an energy-resolving photon-counting pixel detector for spectrometric measurements

    CERN Document Server

    Zang, A; Ballabriga, R; Bisello, F; Campbell, M; Celi, J C; Fauler, A; Fiederle, M; Jensch, M; Kochanski, N; Llopart, X; Michel, N; Mollenhauer, U; Ritter, I; Tennert, F; Wölfel, S; Wong, W; Michel, T

    2015-01-01

    The Dosepix detector is a hybrid photon-counting pixel detector based on ideas of the Medipix and Timepix detector family. 1 mm thick cadmium telluride and 300 μm thick silicon were used as sensor material. The pixel matrix of the Dosepix consists of 16 x 16 square pixels with 12 rows of (200 μm)2 and 4 rows of (55 μm)2 sensitive area for the silicon sensor layer and 16 rows of pixels with 220 μm pixel pitch for CdTe. Besides digital energy integration and photon-counting mode, a novel concept of energy binning is included in the pixel electronics, allowing energy-resolved measurements in 16 energy bins within one acquisition. The possibilities of this detector concept range from applications in personal dosimetry and energy-resolved imaging to quality assurance of medical X-ray sources by analysis of the emitted photon spectrum. In this contribution the Dosepix detector, its response to X-rays as well as spectrum measurements with Si and CdTe sensor layer are presented. Furthermore, a first evaluation wa...

  9. A pixellated γ-camera based on CdTe detectors clinical interests and performances

    International Nuclear Information System (INIS)

    Chambron, J.; Arntz, Y.; Eclancher, B.; Scheiber, Ch.; Siffert, P.; Hage Hali, M.; Regal, R.; Kazandjian, A.; Prat, V.; Thomas, S.; Warren, S.; Matz, R.; Jahnke, A.; Karman, M.; Pszota, A.; Nemeth, L.

    2000-01-01

    A mobile gamma camera dedicated to nuclear cardiology, based on a 15 cmx15 cm detection matrix of 2304 CdTe detector elements, 2.83 mmx2.83 mmx2 mm, has been developed with a European Community support to academic and industrial research centres. The intrinsic properties of the semiconductor crystals - low-ionisation energy, high-energy resolution, high attenuation coefficient - are potentially attractive to improve the γ-camera performances. But their use as γ detectors for medical imaging at high resolution requires production of high-grade materials and large quantities of sophisticated read-out electronics. The decision was taken to use CdTe rather than CdZnTe, because the manufacturer (Eurorad, France) has a large experience for producing high-grade materials, with a good homogeneity and stability and whose transport properties, characterised by the mobility-lifetime product, are at least 5 times greater than that of CdZnTe. The detector matrix is divided in 9 square units, each unit is composed of 256 detectors shared in 16 modules. Each module consists in a thin ceramic plate holding a line of 16 detectors, in four groups of four for an easy replacement, and holding a special 16 channels integrated circuit designed by CLRC (UK). A detection and acquisition logic based on a DSP card and a PC has been programmed by Eurorad for spectral and counting acquisition modes. Collimators LEAP and LEHR from commercial design, mobile gantry and clinical software were provided by Siemens (Germany). The γ-camera head housing, its general mounting and the electric connections were performed by Phase Laboratory (CNRS, France). The compactness of the γ-camera head, thin detectors matrix, electronic readout and collimator, facilitates the detection of close γ sources with the advantage of a high spatial resolution. Such an equipment is intended to bedside explorations. There is a growing clinical requirement in nuclear cardiology to early assess the extent of an infarct

  10. Development of a customized SSC pixel detector readout for vertex tracking

    International Nuclear Information System (INIS)

    Barkan, O.; Atlas, E.L.; Marking, W.L.; Worley, S.; Yacoub, G.Y.; Kramer, G.; Arens, J.F.; Jernigan, J.G.; Shapiro, S.L.; Nygren, D.; Spieler, H.; Wright, M.

    1990-01-01

    The authors describe the readout architecture and progress to date in the development of hybrid PIN diode arrays for use as vertex detectors in the SSC environment. The architecture supports a self-timed mechanism for time stamping hit pixels, storing their xy coordinates and later selectively reading out only those pixels containing interesting data along with their coordinates. The peripheral logic resolves ambiguous pixel ghost locations and controls pixel neighbor readout to achieve high spatial resolution. A test lot containing 64 x 32 pixel arrays has been processed and is currently being tested. Each pixel contains 23 transistors and six capacitors consuming an area of 50μm by 150μm and dissipating about 20μW of power

  11. CdTe hybrid pixel detector for imaging with thermal neutrons

    Czech Academy of Sciences Publication Activity Database

    Jakůbek, J.; Mettivier, G.; Montesi, M.C.; Pospíšil, S.; Russo, P.; Vacík, Jiří

    2006-01-01

    Roč. 563, č. 1 (2006), s. 238-241 ISSN 0168-9002 R&D Pro jects: GA MŠk 1P04LA211 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutronography * pixel detector * semiconductor detector Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.185, year: 2006

  12. Pixel array detector for X-ray free electron laser experiments

    Energy Technology Data Exchange (ETDEWEB)

    Philipp, Hugh T., E-mail: htp2@cornell.edu [Department of Physics, Laboratory of Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Hromalik, Marianne [Electrical and Computer Engineering, SUNY Oswego, Oswego, NY 13126 (United States); Tate, Mark; Koerner, Lucas [Department of Physics, Laboratory of Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M. [Department of Physics, Laboratory of Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Wilson Laboratory, Cornell University, CHESS, Ithaca, NY 14853 (United States)

    2011-09-01

    X-ray free electron lasers (XFELs) promise to revolutionize X-ray science with extremely high peak brilliances and femtosecond X-ray pulses. This will require novel detectors to fully realize the potential of these new sources. There are many current detector development projects aimed at the many challenges of meeting the XFEL requirements . This paper describes a pixel array detector (PAD) that has been developed for the Coherent X-ray Imaging experiment at the Linac Coherent Light Source (LCLS) at the SLAC National Laboratory . The detector features 14-bit in-pixel digitization; a 2-level in-pixel gain setting that can be used to make an arbitrary 2-D gain pattern that is adaptable to a particular experiment; the ability to handle instantaneous X-ray flux rates of 10{sup 17} photons per second; and continuous frames rates in excess of 120 Hz. The detector uses direct detection of X-rays in a silicon diode. The charge produced by the diode is integrated in a pixilated application specific integrated circuit (ASIC) which digitizes collected holes with single X-ray photon capability. Each ASIC is 194x185 pixels, each pixel is 110{mu}mx110{mu}m on a side. Each pixel can detect up to 2500 X-rays per frame in low-gain mode, yet easily detects single photons at high-gain. Cooled, single-chip detectors have been built and meet all the required specifications. SLAC National Laboratory is engaged in constructing a tiled, multi-chip 1516x1516 pixel detector.

  13. Radiation Damage Monitoring in the ATLAS Pixel Detector

    CERN Document Server

    Seidel, S

    2013-01-01

    We describe the implementation of radiation damage monitoring using measurement of leakage current in the ATLAS silicon pixel sensors. The dependence of the leakage current upon the integrated luminosity is presented. The measurement of the radiation damage corresponding to integrated luminosity 5.6 fb$^{-1}$ is presented along with a comparison to the theoretical model.

  14. Operational experience with the CMS pixel detector in LHC Run II

    CERN Document Server

    Karancsi, Janos

    2016-01-01

    The CMS pixel detector was repaired successfully, calibrated and commissioned for the second run of Large Hadron Collider during the first long shutdown between 2013 and 2015. The replaced pixel modules were calibrated separately and show the expected behavior of an un-irradiated detector. In 2015, the system performed very well with an even improved spatial resolution compared to 2012. During this time, the operational team faced various challenges including the loss of a sector in one half shell which was only partially recovered. In 2016, the detector is expected to withstand instantaneous luminosities beyond the design limits and will need a combined effort of both online and offline teams in order to provide the high quality data that is required to reach the physics goals of CMS. We present the operational experience gained during the second run of the LHC and show the latest performance results of the CMS pixel detector.

  15. Monte Carlo simulation of the response of a pixellated 3D photo-detector in silicon

    CERN Document Server

    Dubaric, E; Froejdh, C; Norlin, B

    2002-01-01

    The charge transport and X-ray photon absorption in three-dimensional (3D) X-ray pixel detectors have been studied using numerical simulations. The charge transport has been modelled using the drift-diffusion simulator MEDICI, while photon absorption has been studied using MCNP. The response of the entire pixel detector system in terms of charge sharing, line spread function and modulation transfer function, has been simulated using a system level Monte Carlo simulation approach. A major part of the study is devoted to the effect of charge sharing on the energy resolution in 3D-pixel detectors. The 3D configuration was found to suppress charge sharing much better than conventional planar detectors.

  16. The Layer 1 / Layer 2 readout upgrade for the ATLAS Pixel Detector

    CERN Document Server

    Mullier, Geoffrey; The ATLAS collaboration

    2016-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of the Large Hadron Collider (LHC). The increase of instantaneous luminosity foreseen during the LHC Run 2, will lead to an increased detector occupancy that is expected to saturate the readout links of the outermost layers of the pixel detector: Layers 1 and 2. To ensure a smooth data taking under such conditions, the read out system of the recently installed fourth innermost pixel layer, the Insertable B-Layer, was modified to accomodate the needs of the older detector. The Layer 2 upgrade installation took place during the 2015 winter shutdown, with the Layer 1 installation scheduled for 2016. A report of the successful installation, together with the design of novel dedicated optical to electrical converters and the software and firmware updates will be presented.

  17. DEPFET active pixel detectors for a future linear $e^+e^-$ collider

    CERN Document Server

    Alonso, O; Dieguez, A; Dingfelder, J; Hemperek, T; Kishishita, T; Kleinohl, T; Koch, M; Krueger, H; Lemarenko, M; Luetticke, F; Marinas, C; Schnell, M; Wermes, N; Campbell, A; Ferber, T; Kleinwort, C; Niebuhr, C; Soloviev, Y; Steder, M; Volkenborn, R; Yaschenko, S; Fischer, P; Kreidl, C; Peric, I; Knopf, J; Ritzert, M; Curras, E; Lopez-Virto, A; Moya, D; Vila, I; Boronat, M; Esperante, D; Fuster, J; Garcia Garcia, I; Lacasta, C; Oyanguren, A; Ruiz, P; Timon, G; Vos, M; Gessler, T; Kuehn, W; Lange, S; Muenchow, D; Spruck, B; Frey, A; Geisler, C; Schwenker, B; Wilk, F; Barvich, T; Heck, M; Heindl, S; Lutz, O; Mueller, Th; Pulvermacher, C; Simonis, H.J; Weiler, T; Krausser, T; Lipsky, O; Rummel, S; Schieck, J; Schlueter, T; Ackermann, K; Andricek, L; Chekelian, V; Chobanova, V; Dalseno, J; Kiesling, C; Koffmane, C; Gioi, L.Li; Moll, A; Moser, H.G; Mueller, F; Nedelkovska, E; Ninkovic, J; Petrovics, S; Prothmann, K; Richter, R; Ritter, A; Ritter, M; Simon, F; Vanhoefer, P; Wassatsch, A; Dolezal, Z; Drasal, Z; Kodys, P; Kvasnicka, P; Scheirich, J

    2013-01-01

    The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\\mathrm{\\mathbf{\\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\\mathbf{e^+ e^-}$ collider.

  18. Data acquisition at the front-end of the Mu3e pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Perrevoort, Ann-Kathrin [Physikalisches Institut, Universitaet Heidelberg (Germany); Collaboration: Mu3e-Collaboration

    2016-07-01

    The Mu3e experiment - searching for the lepton-flavour violating decay of the muon into three electrons at an unprecedented sensitivity of one in 10{sup 16} decays - is based on a pixel tracking detector. The sensors are High-Voltage Monolithic Active Pixel Sensors, a technology which allows for very fast and thin detectors, and thus is an ideal fit for Mu3e where the trajectories of low-momentum electrons at high rates are to be measured. The detector will consist of about 275 million pixels and will be operated at up to 10{sup 9} muon stops per second. Therefore, a fast and trigger-less data readout is required. The pixel sensors feature zero-suppressed data output via high-speed serial links. The data is then buffered and sorted by time on a FPGA on the front-end before being processed to the following readout stage. In this talk, the readout of the Mu3e pixel detector at the front-end is introduced. Furthermore, a first firmware implementation of this concept in a beam telescope consisting of the current pixel sensor prototype MuPix7 is presented.

  19. ATLAS SemiConductor Tracker and Pixel Detector: Status and Performance

    CERN Document Server

    Reeves, K; The ATLAS collaboration

    2012-01-01

    The Semi-Conductor Tracker (SCT) and the Pixel Detector are the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is a silicon strip detector and is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals from the strips are processed in the front-end ASICS ABCD3TA, working in the binary readout mode. The Pixel Detector consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In the talk the current status of the SCT and Pixel Detector will be reviewed. We will report on the operation of the detectors including an overview of the issues we encountered and the observation of significant increases in leakage currents (as expected) from bulk ...

  20. Novel powering schemes for pixel and tracking detectors

    CERN Document Server

    Feld, Lutz Werner

    2013-01-01

    Future pixel and tracking systems like the ones foreseen in the upgrade programs of the LHC experiments are very demanding on the power supply systems. An increased amount of power has to be supplied to the front-end electronics at a reduced voltage, through existing cable plants. Novel powering schemes are needed to avoid excessive cable losses. The two schemes under consideration, serial powering and DC-DC conversion, are reviewed. Particular emphasis is put on system integration aspects. As an example, the new CMS pixel system, which will be powered via DC-DC conversion, is presented in more detail. This allows to discuss challenges and solutions for a concrete application while the conclusions should be relevant for other applications as well.

  1. Pixel detector bias supply and control using embedded multicore processors

    CERN Document Server

    AUTHOR|(CDS)2099144; Akram Alomainy

    The aim of the project is to create a software controlled, open source, low footprint and low power high voltage bias supply and current monitor for a pixelated radiation sensor. The solution is based on the LT3905 integrated circuit and the multi-core XMOS xCore 200 microcontroller and it is intended to be used in a battery powered, mobile platform for educational settings.

  2. Commissioning and first results from the CMS phase-1 upgrade pixel detector

    CERN Document Server

    Sonneveld, Jorine Mirjam

    2017-01-01

    The phase~1 upgrade of the CMS pixel detector has been designed to maintain the tracking performance at instantaneous luminosities of $2 \\times 10^{34} \\mathrm{~cm}^{-2} \\mathrm{~s}^{-1}$. Both barrel and endcap disk systems now feature one extra layer (4 barrel layers and 3 endcap disks), and a digital readout that provides a large enough bandwidth to read out its 124M pixel channels (87.7 percent more pixels compared to the previous system). The backend control and readout systems have been upgraded accordingly from VME-based to micro-TCA-based ones. The detector is now also fitted with a bi-phase CO$_2$ cooling system that reduces the material budget in the tracking region. The detector has been installed inside CMS at the start of 2017 and is now taking data. These proceedings discuss experiences in the commissioning and operation of the CMS phase~1 pixel detector. The first results from the CMS phase~1 pixel detector with this year's LHC proton-proton collision data are presented. ...

  3. A new generation of small pixel pitch/SWaP cooled infrared detectors

    Science.gov (United States)

    Espuno, L.; Pacaud, O.; Reibel, Y.; Rubaldo, L.; Kerlain, A.; Péré-Laperne, N.; Dariel, A.; Roumegoux, J.; Brunner, A.; Kessler, A.; Gravrand, O.; Castelein, P.

    2015-10-01

    Following clear technological trends, the cooled IR detectors market is now in demand for smaller, more efficient and higher performance products. This demand pushes products developments towards constant innovations on detectors, read-out circuits, proximity electronics boards, and coolers. Sofradir was first to show a 10μm focal plane array (FPA) at DSS 2012, and announced the DAPHNIS 10μm product line back in 2014. This pixel pitch is a key enabler for infrared detectors with increased resolution. Sofradir recently achieved outstanding products demonstrations at this pixel pitch, which clearly demonstrate the benefits of adopting 10μm pixel pitch focal plane array-based detectors. Both HD and XGA Daphnis 10μm products also benefit from a global video datapath efficiency improvement by transitioning to digital video interfaces. Moreover, innovative smart pixels functionalities drastically increase product versatility. In addition to this strong push towards a higher pixels density, Sofradir acknowledges the need for smaller and lower power cooled infrared detector. Together with straightforward system interfaces and better overall performances, latest technological advances on SWAP-C (Size, Weight, Power and Cost) Sofradir products enable the advent of a new generation of high performance portable and agile systems (handheld thermal imagers, unmanned aerial vehicles, light gimbals etc...). This paper focuses on those features and performances that can make an actual difference in the field.

  4. The ALICE silicon pixel detector front-end and read-out electronics

    CERN Document Server

    Kluge, A

    2006-01-01

    The ALICE silicon pixel detector (SPD) comprises the two innermost barrel layers of the ALICE inner tracker system. The SPD includes 120 half staves each of which consists of a linear array of 10 ALICE pixel chips bump bonded to two silicon sensors. Each pixel chip contains 8192 active cells, so the total number of pixel cells in the SPD is ≈107. The tight material budget and the limitation in physical dimensions required by the detector design introduce new challenges for the integration of the on-detector electronics. An essential part of the half stave is a low-mass multi-layer flex that carries power, ground, and signals to the pixel chips. Each half stave is read out using a multi-chip module (MCM). The MCM contains three radiation hard ASICs and an 800 Mbit/s custom developed optical link for the data transfer between the detector and the control room. The detector components are less than 3 mm thick. The production of the half-staves and MCMs is currently under way. Test results as well as on overvie...

  5. Pre- and post-irradiation performance of FBK 3D silicon pixel detectors for CMS

    International Nuclear Information System (INIS)

    Krzywda, A.; Alagoz, E.; Bubna, M.; Obertino, M.; Solano, A.; Arndt, K.; Uplegger, L.; Betta, G.F. Dalla; Boscardin, M.; Ngadiuba, J.; Rivera, R.; Menasce, D.; Moroni, L.; Terzo, S.; Bortoletto, D.; Prosser, A.; Adreson, J.; Kwan, S.; Osipenkov, I.; Bolla, G.

    2014-01-01

    In preparation for the tenfold luminosity upgrade of the Large Hadron Collider (the HL-LHC) around 2020, three-dimensional (3D) silicon pixel sensors are being developed as a radiation-hard candidate to replace the planar ones currently being used in the CMS pixel detector. This study examines an early batch of FBK sensors (named ATLAS08) of three 3D pixel geometries: 1E, 2E, and 4E, which respectively contain one, two, and four readout electrodes for each pixel, passing completely through the bulk. We present electrical characteristics and beam test performance results for each detector before and after irradiation. The maximum fluence applied is 3.5×10 15 n eq /cm 2

  6. Studies for the detector control system of the ATLAS pixel at the HL-LHC

    International Nuclear Information System (INIS)

    Püllen, L; Becker, K; Boek, J; Kersten, S; Kind, P; Mättig, P; Zeitnitz, C

    2012-01-01

    In the context of the LHC upgrade to the HL-LHC the inner detector of the ATLAS experiment will be replaced completely. As part of this redesign there will also be a new pixel detector. This new pixel detector requires a control system which meets the strict space requirements for electronics in the ATLAS experiment. To accomplish this goal we propose a DCS (Detector Control System) network with the smallest form factor currently available. This network consists of a DCS chip located in close proximity to the interaction point and a DCS controller located in the outer regions of the ATLAS detector. These two types of chips form a star shaped network with several DCS chips being controlled by one DCS controller. Both chips are manufactured in deep sub-micron technology. We present prototypes with emphasis on studies concerning single event upsets.

  7. arXiv Performance verification of the CMS Phase-1 Upgrade Pixel detector

    CERN Document Server

    Veszpremi, Viktor

    2017-12-04

    The CMS tracker consists of two tracking systems utilizing semiconductor technology: the inner pixel and the outer strip detectors. The tracker detectors occupy the volume around the beam interaction region between 3 cm and 110 cm in radius and up to 280 cm along the beam axis. The pixel detector consists of 124 million pixels, corresponding to about 2 m 2 total area. It plays a vital role in the seeding of the track reconstruction algorithms and in the reconstruction of primary interactions and secondary decay vertices. It is surrounded by the strip tracker with 10 million read-out channels, corresponding to 200 m 2 total area. The tracker is operated in a high-occupancy and high-radiation environment established by particle collisions in the LHC . The current strip detector continues to perform very well. The pixel detector that has been used in Run 1 and in the first half of Run 2 was, however, replaced with the so-called Phase-1 Upgrade detector. The new system is better suited to match the increased inst...

  8. Low-cost bump-bonding processes for high energy physics pixel detectors

    CERN Document Server

    AUTHOR|(CDS)2069357; Blank, Thomas; Colombo, Fabio; Dierlamm, Alexander Hermann; Husemann, Ulrich; Kudella, Simon; Weber, M

    2016-01-01

    In the next generation of collider experiments detectors will be challenged by unprecedented particle fluxes. Thus large detector arrays of highly pixelated detectors with minimal dead area will be required at reasonable costs. Bump-bonding of pixel detectors has been shown to be a major cost-driver. KIT is one of five production centers of the CMS barrel pixel detector for the Phase I Upgrade. In this contribution the SnPb bump-bonding process and the production yield is reported. In parallel to the production of the new CMS pixel detector, several alternatives to the expensive photolithography electroplating/electroless metal deposition technologies are developing. Recent progress and challenges faced in the development of bump-bonding technology based on gold-stud bonding by thin (15 μm) gold wire is presented. This technique allows producing metal bumps with diameters down to 30 μm without using photolithography processes, which are typically required to provide suitable under bump metallization. The sh...

  9. The construction of the phase 1 upgrade of the CMS pixel detector

    CERN Document Server

    Weber, Hannsjorg Artur

    2017-01-01

    The innermost layers of the original CMS tracker were built out of pixel detectors arranged in three barrel layers and two forward disks in each endcap. The original CMS detector was designed for the nominal instantaneous LHC luminosity of $1\\times10^{34}\\,\\text{cm}^{-2}\\text{s}^{-1}$. Under the conditions expected in the coming years, which will see an increase of a factor two of the instantaneous luminosity, the CMS pixel detector would have seen a dynamic inefficiency caused by data losses due to buffer overflows. For this reason the CMS collaboration has installed during the recent extended end of year shutdown a replacement pixel detector. The phase-1 upgrade of the CMS pixel detector will operate at high efficiency at an instantaneous luminosity of $2\\times10^{34}\\,\\text{cm}^{-2}\\text{s}^{-1}$ with increased detector acceptance and additional redundancy for the tracking, while at the same time reducing the material budget. These goals are achieved using a new read-out chip and modified powering and rea...

  10. A MCM-D-type module for the ATLAS pixel detector

    CERN Document Server

    Becks, K H; Ehrmann, O; Gerlach, P; Gregor, I M; Pieters, P; Topper, M; Truzzi, C; Wolf, J

    1999-01-01

    For the ATLAS experiment at the planned Large Hadron Collider LHC at CERN hybrid pixel detectors are being built as innermost layers of the inner tracking detector system. Modules are the basic building blocks of the ATLAS pixel $9 detector. A module consists of a sensor tile with an active area of 16.4 mm*60.4 mm, 16 read out IC's, each serving 24*160 pixel unit cells, a module controller chip, an optical transceiver and the local signal interconnection and $9 power distribution busses. The dies are attached by flip-chip assembly to the sensor diodes and the local busses. In the following a module based on MCM-D technology will be discussed and prototype results will be presented.

  11. Operating characteristics of radiation-hardened silicon pixel detectors for the CMS experiment

    CERN Document Server

    Hyosung, Cho

    2002-01-01

    The Compact Muon Solenoid (CMS) experiment at the CERN Large Hadron Collider (LHC) will have forward silicon pixel detectors as its innermost tracking device. The pixel devices will be exposed to the harsh radiation environment of the LHC. Prototype silicon pixel detectors have been designed to meet the specification of the CMS experiment. No guard ring is required on the n/sup +/ side, and guard rings on the p/sup +/ side are always kept active before and after type inversion. The whole n/sup +/ side is grounded and connected to readout chips, which greatly simplifies detector assembling and improves the stability of bump-bonded readout chips on the n/sup +/ side. Operating characteristics such as the leakage current, the full depletion voltage, and the potential distributions over guard rings were tested using standard techniques. The tests are discussed in this paper. (9 refs).

  12. 14C autoradiography with an energy-sensitive silicon pixel detector.

    Science.gov (United States)

    Esposito, M; Mettivier, G; Russo, P

    2011-04-07

    The first performance tests are presented of a carbon-14 ((14)C) beta-particle digital autoradiography system with an energy-sensitive hybrid silicon pixel detector based on the Timepix readout circuit. Timepix was developed by the Medipix2 Collaboration and it is similar to the photon-counting Medipix2 circuit, except for an added time-based synchronization logic which allows derivation of energy information from the time-over-threshold signal. This feature permits direct energy measurements in each pixel of the detector array. Timepix is bump-bonded to a 300 µm thick silicon detector with 256 × 256 pixels of 55 µm pitch. Since an energetic beta-particle could release its kinetic energy in more than one detector pixel as it slows down in the semiconductor detector, an off-line image analysis procedure was adopted in which the single-particle cluster of hit pixels is recognized; its total energy is calculated and the position of interaction on the detector surface is attributed to the centre of the charge cluster. Measurements reported are detector sensitivity, (4.11 ± 0.03) × 10(-3) cps mm(-2) kBq(-1) g, background level, (3.59 ± 0.01) × 10(-5) cps mm(-2), and minimum detectable activity, 0.0077 Bq. The spatial resolution is 76.9 µm full-width at half-maximum. These figures are compared with several digital imaging detectors for (14)C beta-particle digital autoradiography.

  13. Recent progress in the development of a B-factory monolithic active pixel detector

    International Nuclear Information System (INIS)

    Stanic, S.; Aihara, H.; Barbero, M.; Bozek, A.; Browder, T.; Hazumi, M.; Kennedy, J.; Kent, N.; Olsen, S.; Palka, H.; Rosen, M.; Ruckman, L.; Trabelsi, K.; Tsuboyama, T.; Uchida, K.; Varner, G.; Yang, Q.

    2006-01-01

    Due to the need for precise vertexing at future higher luminosity B-factories with the expectedly increasing track densities and radiation exposures, upgrade of present silicon strip detectors with thin, radiation resistant pixel detectors is highly desired. Considerable progress in the technological development of thin CMOS based Monolithic Active Pixel Sensors (MAPS) in the last years makes them a realistic upgrade option and the feasibility studies of their application in Belle are actively pursued. The most serious concerns are their radiation hardness and their read-out speed. To address them, several prototypes denoted as Continuous Acquisition Pixel (CAP) sensors have been developed and tested. The latest of the CAP sensor prototypes is CAP3, designed in the TSMC 0.25μm process with a 5-deep sample pair pipeline in each pixel. A setup with several CAP3 sensors will be used to assess the performance of a full scale pixel read-out system running at realistic read-out speed. The results and plans for the next stages of R and D towards a full Pixel Vertex Detector (PVD) are presented

  14. Performance of the Insertable B-Layer for the ATLAS Pixel Detector during Quality Assurance and a Novel Pixel Detector Readout Concept based on PCIe

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00356268; Pernegger, Heinz

    2016-07-27

    During the first long shutdown of the LHC the Pixel detector has been upgraded with a new 4th innermost layer, the Insertable B-Layer (IBL). The IBL will increase the tracking performance and help with higher than nominal luminosity the LHC will produce. The IBL is made up of 14 staves and in total 20 staves have been produced for the IBL. This thesis presents the results of the final quality tests performed on these staves in an detector-like environment, in order to select the 14 best of the 20 staves for integration onto the detector. The test setup as well as the testing procedure is introduced and typical results of each testing stage are shown and discussed. The overall performance of all staves is presented in regards to: tuning performance, radioactive source measurements, and number of failing pixels. Other measurement, which did not directly impact the selection of staves, but will be important for the operation of the detector or production of a future detector, are included. Based on the experienc...

  15. Performance of silicon pixel detectors at small track incidence angles for the ATLAS Inner Tracker upgrade

    International Nuclear Information System (INIS)

    Viel, Simon; Banerjee, Swagato; Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice; Hard, Andrew Straiton; Kaplan, Laser Seymour; Kashif, Lashkar; Pranko, Aliaksandr; Rieger, Julia; Wolf, Julian; Wu, Sau Lan; Yang, Hongtao

    2016-01-01

    In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN. - Highlights: • Extended inner pixel barrel layers are proposed for the ATLAS ITk upgrade. • Test beam results at small track incidence angles validate this ATLAS ITk design. • Long pixel clusters are reconstructed with high efficiency at low threshold values. • Excellent angular resolution is achieved using pixel cluster length information.

  16. Performance of silicon pixel detectors at small track incidence angles for the ATLAS Inner Tracker upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Viel, Simon, E-mail: sviel@lbl.gov [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Banerjee, Swagato [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States); Brandt, Gerhard; Carney, Rebecca; Garcia-Sciveres, Maurice [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Hard, Andrew Straiton; Kaplan, Laser Seymour; Kashif, Lashkar [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States); Pranko, Aliaksandr [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Rieger, Julia [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); II Physikalisches Institut, Georg-August-Universität, Göttingen (Germany); Wolf, Julian [Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America (United States); Wu, Sau Lan; Yang, Hongtao [Department of Physics, University of Wisconsin, Madison, WI, United States of America (United States)

    2016-09-21

    In order to enable the ATLAS experiment to successfully track charged particles produced in high-energy collisions at the High-Luminosity Large Hadron Collider, the current ATLAS Inner Detector will be replaced by the Inner Tracker (ITk), entirely composed of silicon pixel and strip detectors. An extension of the tracking coverage of the ITk to very forward pseudorapidity values is proposed, using pixel modules placed in a long cylindrical layer around the beam pipe. The measurement of long pixel clusters, detected when charged particles cross the silicon sensor at small incidence angles, has potential to significantly improve the tracking efficiency, fake track rejection, and resolution of the ITk in the very forward region. The performance of state-of-the-art pixel modules at small track incidence angles is studied using test beam data collected at SLAC and CERN. - Highlights: • Extended inner pixel barrel layers are proposed for the ATLAS ITk upgrade. • Test beam results at small track incidence angles validate this ATLAS ITk design. • Long pixel clusters are reconstructed with high efficiency at low threshold values. • Excellent angular resolution is achieved using pixel cluster length information.

  17. Prospects for hybrid pixel detectors in electron microscopy

    International Nuclear Information System (INIS)

    Faruqi, A.R.

    2001-01-01

    The current status of CCD-based detectors for cryo-electron microscopy of membrane and other proteins is described briefly, highlighting the strengths and weaknesses of the technique. Over the past few years CCD detectors have been used extensively in electron crystallography of membrane proteins, and in particular, in the study of the molecular transitions which take place during the photo-cycle of the light-driven proton pump bacteriorhodopsin. Direct-detection methods, which avoid the intermediate stages of converting the electron energy into light, offer the possibility of improved spatial resolution compared to CCD detectors; in addition, photon counting and noise-free readout should improve the signal-to-noise ratio

  18. Status of the ATLAS Pixel Detector at the LHC and its performance after three years of operation

    CERN Document Server

    Andreazza, A; The ATLAS collaboration

    2012-01-01

    The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN, providing high-resolution measurements of charged particle tracks in the high radiation environment close to the collision region. This capability is vital for the identification and measurement of proper decay times of long-lived particles such as b-hadrons, and thus vital for the ATLAS physics program. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 million pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. In this talk, results from the successful operation of the Pixel Detector at the LHC and its status after three years of operation will be presented, including monitoring, calibration procedures, timing optimization and detector performance. The detector performance is excellent: ~96 % of the pixels are operational, noise occupancy and hit ...

  19. 18F-FDG positron autoradiography with a particle counting silicon pixel detector.

    Science.gov (United States)

    Russo, P; Lauria, A; Mettivier, G; Montesi, M C; Marotta, M; Aloj, L; Lastoria, S

    2008-11-07

    We report on tests of a room-temperature particle counting silicon pixel detector of the Medipix2 series as the detector unit of a positron autoradiography (AR) system, for samples labelled with (18)F-FDG radiopharmaceutical used in PET studies. The silicon detector (1.98 cm(2) sensitive area, 300 microm thick) has high intrinsic resolution (55 microm pitch) and works by counting all hits in a pixel above a certain energy threshold. The present work extends the detector characterization with (18)F-FDG of a previous paper. We analysed the system's linearity, dynamic range, sensitivity, background count rate, noise, and its imaging performance on biological samples. Tests have been performed in the laboratory with (18)F-FDG drops (37-37 000 Bq initial activity) and ex vivo in a rat injected with 88.8 MBq of (18)F-FDG. Particles interacting in the detector volume produced a hit in a cluster of pixels whose mean size was 4.3 pixels/event at 11 keV threshold and 2.2 pixels/event at 37 keV threshold. Results show a sensitivity for beta(+) of 0.377 cps Bq(-1), a dynamic range of at least five orders of magnitude and a lower detection limit of 0.0015 Bq mm(-2). Real-time (18)F-FDG positron AR images have been obtained in 500-1000 s exposure time of thin (10-20 microm) slices of a rat brain and compared with 20 h film autoradiography of adjacent slices. The analysis of the image contrast and signal-to-noise ratio in a rat brain slice indicated that Poisson noise-limited imaging can be approached in short (e.g. 100 s) exposures, with approximately 100 Bq slice activity, and that the silicon pixel detector produced a higher image quality than film-based AR.

  20. Signal height in silicon pixel detectors irradiated with pions and protons

    International Nuclear Information System (INIS)

    Rohe, T.; Acosta, J.; Bean, A.; Dambach, S.; Erdmann, W.; Langenegger, U.; Martin, C.; Meier, B.; Radicci, V.; Sibille, J.; Trueb, P.

    2010-01-01

    Pixel detectors are used in the innermost part of multi-purpose experiments at the Large Hadron Collider (LHC) and are therefore exposed to the highest fluences of ionising radiation, which in this part of the detectors consists mainly of charged pions. The radiation hardness of the detectors has been tested thoroughly up to the fluences expected at the LHC. In case of an LHC upgrade the fluence will be much higher and it is not yet clear up to which radii the present pixel technology can be used. To establish such a limit, pixel sensors of the size of one CMS pixel readout chip (PSI46V2.1) have been bump bonded and irradiated with positive pions up to 6x10 14 n eq /cm 2 at PSI and with protons up to 5x10 15 n eq /cm 2 . The sensors were taken from production wafers of the CMS barrel pixel detector. They use n-type DOFZ material with a resistance of about 3.7kΩcm and an n-side read out. As the performance of silicon sensors is limited by trapping, the response to a Sr-90 source was investigated. The highly energetic beta-particles represent a good approximation to minimum ionising particles. The bias dependence of the signal for a wide range of fluences will be presented.

  1. Geneva University: Pixel Detectors – trends and options for the future

    CERN Multimedia

    Geneva University

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92   Wednesday 25 April 2012 SEMINAIRE DE PHYSIQUE CORPUSCULAIRE Science III, Auditoire 1S081 30Science III, Auditoire 1S081 30 Pixel Detectors – trends and options for the future Prof. Norbert Wermes - University of Bonn  Pixel detectors have been invented in the early 90s with the advancement of micro technologies. With the advent of the LHC, big vertex detectors have demonstrated that the pixel detector type is holding many of the promises it had made before. Meanwhile new, different or just improved variants of the pixel technology are being studied for their suitability for future experiments or experiment upgrades. The talk will address the various pro's and con's comparing hybrid and monolithic pixel technologies and their su...

  2. Development of the MCM-D technique for pixel detector modules

    International Nuclear Information System (INIS)

    Grah, C.

    2005-03-01

    This thesis treats a copper--polymer based thin film technology, the MCM-D technique and its application when building hybrid pixel detector modules. The ATLAS experiment at the LHC will be equipped with a pixel detector system. The basic mechanical units of the pixel detector are multi chip modules. The main components of these modules are: 16 electronic chips, a controller chip and a large sensor tile, featuring more than 46000 sensor cells. MCM-D is a superior technique to build the necessary signal bus system and the power distribution system directly on the active sensor tile. In collaboration with the Fraunhofer Institute for Reliability and Microintegration, IZM, the thin film process is reviewed and enhanced. The multi layer system was designed and optimized for the interconnection system as well as for the 46000 pixel contacts. Laboratory measurements on prototypes prove that complex routing schemes for geometrically optimized single chips are suitable and have negligible influence on the front--end chips performance. A full scale MCM-D module has been built and it is shown that the technology is suitable to build pixel detector modules. Further tests include the investigation of the impact of hadronic irradiation on the thin film layers. Single chip assemblies have been operated in a test beam environment and the feasibility of the optimization of the sensors could be shown. A review on the potential as well as the perspective for the MCM-D technique in future experiments is given

  3. High resolution radiography of ambers with pixel detectors

    Czech Academy of Sciences Publication Activity Database

    Dammer, J.; Weyda, F.; Beneš, J.; Sopko, V.; Jandejsek, I.; Pflegerová, Jitka

    2013-01-01

    Roč. 8, č. 3 (2013), C03024 ISSN 1748-0221. [Conference: International Workshop on Radiation Imaging Detectors /14./. Figueira da Foz, 01.07.2012-05.07.2012] Grant - others:GA ČR(CZ) GA103/09/2101; GA Mšk(CZ) LA08032 Program:GA; LA Institutional support: RVO:60077344 Keywords : X-ray detectors * Inspection with x-rays * X-ray radiography and digital radiography (DR) Subject RIV: EA - Cell Biology Impact factor: 1.526, year: 2013 http://iopscience.iop.org/1748-0221/8/03/C03024/

  4. Track parameter resolution study of a pixel only detector for LHC geometry and future high rate experiments

    Energy Technology Data Exchange (ETDEWEB)

    Blago, Michele Piero; Kar, Tamasi Rameshchandra; Schoening, Andre [Physikalisches Institut, Universitaet Heidelberg (Germany)

    2016-07-01

    Recent progress in pixel detector technology, for example using High Voltage-Monolithic Pixel Sensors (HV-MAPS), makes it feasible to construct an all-silicon pixel detector for large scale particle experiments like ATLAS and CMS or other future collider experiments. Preliminary studies have shown that nine layers of pixel sensors are sufficient to reliably reconstruct particle trajectories. The performance of such an all-pixel detector is studied based on a full GEANT simulation for high luminosity conditions at the upgraded LHC. Furthermore, the ability of an all-pixel detector to form trigger decisions using a special triplet pixel layer design is studied. Such a design could be used to reconstruct all tracks originating from the proton-proton interaction at the first hardware level at 40 MHz collision frequency.

  5. Assembly procedure of the module (half-stave) of the ALICE Silicon Pixel Detector

    CERN Document Server

    Caselle, M; Antinori, F; Burns, M; Campbell, M; Chochula, P; Dinapoli, R; Elia, D; Formenti, F; Fini, R A; Ghidini, B; Kluge, A; Lenti, V; Manzari, V; Meddi, F; Morel, M; Navach, F; Nilsson, P; Pepato, Adriano; Riedler, P; Santoro, R; Stefanini, G; Viesti, G; Wyllie, K

    2004-01-01

    The Silicon Pixel Detector (SPD) forms the two innermost layers of the ALICE Inner Tracking System (ITS). The detector includes 1200 readout ASICs, each containing 8192 pixel cells, bump-bonded to Si sensor elements. The thickness of the readout chip and the sensor element is 150mum and 200mum, respectively. Low-mass solutions are implemented for the bus and the mechanical support. In this contribution, we describe the basic module (half-stave) of the two SPD layers and we give an overview of its assembly procedure.

  6. PixTrig: a Level 2 track finding algorithm based on pixel detector

    CERN Document Server

    Baratella, A; Morettini, P; Parodi, F

    2000-01-01

    This note describes an algorithm for track search at Level 2 based on pixel detector. Using three pixel clusters we can produce a reconstruction of the track parameter in both z and R-phi plane. These track segments can be used as seed for more sophisticated track finding algorithms or used directly, especially when impact parameter resolution is crucial. The algorithm efficiency is close to 90% for pt > 1 GeV/c and the processing time is small enough to allow a complete detector reconstruction (non RoI guided) within the Level 2 processing.

  7. Spatial Resolution of the Medipix-2 as Neutron Pixel Detector

    Czech Academy of Sciences Publication Activity Database

    Jakůbek, J.; Holý, T.; Lehmann, E.; Pospíšil, S.; Uher, J.; Vacík, J.; Vavřík, Daniel

    2005-01-01

    Roč. 546, - (2005), s. 164-169 ISSN 0168-9002. [International Workshop on Radiation Imaging Detectors /6./. Glasgow, Scotland, 25.07.2004-29.07.2004] Institutional research plan: CEZ:AV0Z20710524 Keywords : neutron detection * neutronography * X-ray Subject RIV: JB - Sensors, Measurment, Regulation Impact factor: 1.224, year: 2005

  8. Conception and characterization of a virtual coplanar grid for a 11×11 pixelated CZT detector

    Energy Technology Data Exchange (ETDEWEB)

    Espagnet, Romain; Frezza, Andrea [Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec city, QC, Canada G1R 0A6 (Canada); Martin, Jean-Pierre; Hamel, Louis-André [Department of Physics, Université de Montréal, C.P. 6128 Montréal QC, Canada H3C 3J7 (Canada); Després, Philippe, E-mail: philippe.despres@phy.ulaval.ca [Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec city, QC, Canada G1R 0A6 (Canada); Department of Radiation Oncology and Research Center of CHU de Québec - Université Laval, Quebec city, QC Canada G1R 2J6 (Canada)

    2017-07-11

    Due to the low mobility of holes in CZT, commercially available detectors with a relatively large volume typically use a pixelated anode structure. They are mostly used in imaging applications and often require a dense electronic readout scheme. These large volume detectors are also interesting for high-sensitivity applications and a CZT-based blood gamma counter was developed from a 20×20×15 mm{sup 3} crystal available commercially and having a 11×11 pixelated readout scheme. A method is proposed here to reduce the number of channels required to use the crystal in a high-sensitivity counting application, dedicated to pharmacokinetic modelling in PET and SPECT. Inspired by a classic coplanar anode, an implementation of a virtual coplanar grid was done by connecting the 121 pixels of the detector to form intercalated bands. The layout, the front-end electronics and the characterization of the detector in this 2-channel anode geometry is presented. The coefficients required to compensate for electron trapping in CZT were determined experimentally to improve the performance. The resulting virtual coplanar detector has an intrinsic efficiency of 34% and an energy resolution of 8% at 662 keV. The detector's response was linear between 80 keV and 1372 keV. This suggests that large CZT crystals offer an excellent alternative to scintillation detectors for some applications, especially those where high-sensitivity and compactness are required.

  9. Versatile, reprogrammable area pixel array detector for time-resolved synchrotron x-ray applications

    Energy Technology Data Exchange (ETDEWEB)

    Gruner, Sol [Cornell Univ., Ithaca, NY (United States)

    2010-05-01

    The final technical report for DOE grant DE-SC0004079 is presented. The goal of the grant was to perform research, development and application of novel imaging x-ray detectors so as to effectively utilize the high intensity and brightness of the national synchrotron radiation facilities to enable previously unfeasible time-resolved x-ray research. The report summarizes the development of the resultant imaging x-ray detectors. Two types of detector platforms were developed: The first is a detector platform (called a Mixed-Mode Pixel Array Detector, or MM-PAD) that can image continuously at over a thousand images per second while maintaining high efficiency for wide dynamic range signals ranging from 1 to hundreds of millions of x-rays per pixel per image. Research on an even higher dynamic range variant is also described. The second detector platform (called the Keck Pixel Array Detector) is capable of acquiring a burst of x-ray images at a rate of millions of images per second.

  10. Compensation and trapping in CdZnTe radiation detectors studied by thermoelectric emission spectroscopy, thermally stimulated conductivity, and current-voltage measurements

    International Nuclear Information System (INIS)

    James, Ralph B.

    2000-01-01

    In today's commercially available counter-select-grade CdZnTe crystals for radiation detector applications, the thermal ionization energies of the traps and their types, whether electron or hole traps, were measured. The measurements were successfully done using thermoelectric emission spectroscopy (TEES) and thermally stimulated conductivity (TSC). For reliability, the electrical contacts to the sample were found to be very important and, instead of Au Schottky contacts, In Ohmic contacts had to be used. For the filling of the traps, photoexcitation was done at zero bias, at 20K and at wavelengths which gave the maximum bulk photoexcitation for the sample. Between the temperature range from 20 to 400 K, the TSC current was found to be on the order of ∼ 10,000 times or even larger than the TEES current, in agreement with theory, but only TEES could resolve the trap type and was sensitive to the deep traps. Large concentration of hole traps at 0.1 and 0.6 eV were observed and smaller contraction of electron traps at 0.4 eV was seen. These deep traps cause compensation in the material and also cause trapping that degrades the radiation detection measurement

  11. Monte Carlo simulation of the imaging properties of scintillator-coated X-ray pixel detectors

    International Nuclear Information System (INIS)

    Hjelm, M.; Norlin, B.; Nilsson, H.-E.; Froejdh, C.; Badel, X.

    2003-01-01

    The spatial resolution of scintillator-coated X-ray pixel detectors is usually limited by the isotropic light spread in the scintillator. One way to overcome this limitation is to use a pixellated scintillating layer on top of the semiconductor pixel detector. Using advanced etching and filling techniques, arrays of CsI columns have been successfully fabricated and characterized. Each CsI waveguide matches one pixel of the semiconductor detector, limiting the spatial spread of light. Another concept considered in this study is to detect the light emitted from the scintillator by diodes formed in the silicon pore walls. There is so far no knowledge regarding the theoretical limits for these two approaches, which makes the evaluation of the fabrication process difficult. In this work we present numerical calculations of the signal-to-noise ratio (SNR) for detector designs based on scintillator-filled pores in silicon. The calculations are based on separate Monte Carlo (MC) simulations of X-ray absorption and light transport in scintillator waveguides. The resulting data are used in global MC simulations of flood exposures of the detector array, from which the SNR values are obtained. Results are presented for two scintillator materials, namely CsI(Tl) and GADOX

  12. Development of Micromegas-like gaseous detectors using a pixel readout chip as collecting anode

    International Nuclear Information System (INIS)

    Chefdeville, M.

    2009-01-01

    This thesis reports on the fabrication and test of a new gaseous detector with a very large number of readout channels. This detector is intended for measuring the tracks of charged particles with an unprecedented sensitivity to single electrons of almost 100 %. It combines a metal grid for signal amplification called the Micromegas with a pixel readout chip as signal collecting anode and is dubbed GridPix. GridPix is a potential candidate for a sub-detector at a future electron linear collider (ILC) foreseen to work in parallel with the LHC around 2020--2030. The tracking capability of GridPix is best exploited if the Micromegas is integrated on the pixel chip. This integrated grid is called InGrid and is precisely fabricated by wafer post-processing. The various steps of the fabrication process and the measurements of its gain, energy resolution and ion back-flow property are reported in this document. Studies of the response of the complete detector formed by an InGrid and a TimePix pixel chip to X-rays and cosmic particles are also presented. In particular, the efficiency for detecting single electrons and the point resolution in the pixel plane are measured. Implications for a GridPix detector at ILC are discussed. (author)

  13. 3D silicon pixel detectors for the High-Luminosity LHC

    CERN Document Server

    Lange, J.

    2016-01-01

    3D silicon pixel detectors have been investigated as radiation-hard candidates for the innermost layers of the HL-LHC upgrade of the ATLAS pixel detector. 3D detectors are already in use today in the ATLAS IBL and AFP experiments. These are based on 50x250 um2 large pixels connected to the FE-I4 readout chip. Detectors of this generation were irradiated to HL-LHC fluences and demonstrated excellent radiation hardness with operational voltages as low as 180 V and power dissipation of 12--15 mW/cm2 at a fluence of about 1e16 neq/cm2, measured at -25 degree C. Moreover, to cope with the higher occupancies expected at the HL-LHC, a first run of a new generation of 3D detectors designed for the HL-LHC was produced at CNM with small pixel sizes of 50x50 and 25x100 um2, matched to the FE-I4 chip. They demonstrated a good performance in the laboratory and in beam tests with hit efficiencies of about 97% at already 1--2V before irradiation.

  14. Testing and Integration of the Service Cylinders for the CMS Phase 1 pixel detector

    CERN Document Server

    Ngadiuba, Jennifer

    2016-01-01

    The present 3-layer CMS pixel detector will be replaced with a new 4-layer pixel system, referred to as Phase~1 upgrade, during the LHC extended technical stop in winter 2016/2017. The upgraded detector will allow to maintain the excellent tracking performance of CMS at the upcoming higher luminosity conditions at the LHC. The addition of an extra layer, closer to the beam pipe, demands a complete redesign of its services. The barrel pixel detector is attached to four half cylinders which carry the services along the beam pipe, accommodate the cooling lines and house the electronics for detector readout and control. The service cylinders are a complex system in design as well as in production due to the large number of channels and tight space requirements. In this document we present the design of the system and discuss the construction and testing of the service cylinders for the barrel pixel detector. Furthermore, we present results of the testing and calibrations carried out with a set of new digital dete...

  15. Tests of a high rate pixel detector for CMS upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Mersi, Stefano [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States). et al.

    2013-07-13

    This is a Technical Scope of Work (TSW) between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of the CMS Pixel group, which consists of individuals from the Bristol University, CERN, Fermilab, Rutherford Laboratory (UK), and National Taiwan University who have committed to participate in beam tests to be carried out during the 2013 - 2014 Fermilab Test Beam Facility program. The TSW is intended solely for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. It reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this TSW to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. This TSW fulfills Article 1 (facilities and scope of work) of the User Agreements signed (or still

  16. Gas pixel detector for X-ray observation

    CERN Document Server

    Attié, D; Chefdeville, M; Colas, P; Delagnes, E; Giomataris, Y; van der Graaf, H; Llopart, X; Timmermans, J; Visschers, J

    2009-01-01

    We report on the status of the R&D for a digital Time Projection Chamber (TPC) based on Micromegas (MICRO MEsh GAseous Structure) detectors using the CMOS chip TimePix as a direct readout anode protected by highly resistive a-Si:H layer. A small chamber was built as a demonstrator of the 2-D and 3-D imaging capabilities of this technique. We illustrate the new capabilities of this detector for X-ray observation with data taken from radioactive sources. This small TPC is a very useful tool both for studying gas properties thanks to its good efficiency for single electrons, and for reconstructing photoelectron direction for use as a soft X-ray polarimeter.

  17. Test-beam Results from a RICH Detector Prototype Using Aerogel Radiator and Pixel Hybrid Photon Detectors

    CERN Document Server

    Aglieri-Rinella, G; Van Lysebetten, A; Piedigrossi, D; Wyllie, K; Bellunato, T F; Calvi, M; Matteuzzi, C; Musy, M; Perego, D L; Somerville, L P; Newby, C; Easo, S; Wotton, S

    2006-01-01

    A test-beam study was performed at CERN with a Ring Imaging Cherenkov (RICH) prototype using three pixel Hybrid Photon Detectors. Results on the photon yield and Cherenkov angle resolution are presented here, for the Aerogel radiator and also for reference runs taken with Nitrogen radiator.

  18. Optical readout and control interface for the BTeV pixel vertex detector

    CERN Document Server

    Vergara-Limon, S; Sheaff, M; Vargas, M A

    2002-01-01

    Optical links will be used for sending data back and forth from the counting room to the detector in the data acquisition systems for future high energy physics experiments, including ATLAS and CMS in the LHC at CERN (Switzerland) and BTeV at Fermilab (USA). This is because they can be ultra-high speed and are relatively immune to electro-magnetic interference (EMI). The baseline design for the BTeV Pixel Vertex Detector includes two types of optical link, one to control and monitor and the other to read out the hit data from the multi-chip modules on each half-plane of the detector. The design and performance of the first prototype of the Optical Readout and Control Interface for the BTeV Pixel Vertex Detector is described.

  19. Silicon micro-fluidic cooling for NA62 GTK pixel detectors

    CERN Document Server

    Romagnoli, G; Brunel, B; Catinaccio, A; Degrange, J; Mapelli, A; Morel, M; Noel, J; Petagna, P

    2015-01-01

    Silicon micro-channel cooling is being studied for efficient thermal management in application fields such as high power computing and 3D electronic integration. This concept has been introduced in 2010 for the thermal management of silicon pixel detectors in high energy physics experiments. Combining the versatility of standard micro-fabrication processes with the high thermal efficiency typical of micro-fluidics, it is possible to produce effective thermal management devices that are well adapted to different detector configurations. The production of very thin cooling devices in silicon enables a minimization of material of the tracking sensors and eliminates mechanical stresses due to the mismatch of the coefficient of thermal expansion between detectors and cooling systems. The NA62 experiment at CERN will be the first high particle physics experiment that will install a micro-cooling system to perform the thermal management of the three detection planes of its Gigatracker pixel detector.

  20. Operational Experience with and Performance of the ATLAS Pixel Detector at the Large Hadron Collider

    CERN Document Server

    Grummer, Aidan; The ATLAS collaboration

    2018-01-01

    The operational experience and requirements to ensure optimum data quality and data taking efficiency with the 4-layer ATLAS Pixel Detector are discussed. The detector has undergone significant hardware and software upgrades to meet the challenges imposed by the fact that the Large Hadron Collider is exceeding expectations for instantaneous luminosity by more than a factor of two (more than $2 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$). Emphasizing radiation damage effects, the key status and performance metrics are described.

  1. Pixellated thallium bromide detectors for gamma-ray spectroscopy and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Onodera, T. E-mail: tosiyuki@smail.tohtech.ac.jp; Hitomi, K.; Shoji, T.; Hiratate, Y

    2004-06-01

    Recently, pixellated semiconductor detectors exhibit high-energy resolution, which have been studied actively and fabricated from CdTe, CZT and HgI{sub 2}. Thallium bromide (TlBr) is a compound semiconductor characterized with its high atomic numbers (Tl=81, Br=35) and high density (7.56 g/cm{sup 3}). Thus, TlBr exhibits higher photon stopping power than other semiconductor materials used for radiation detector fabrication such as CdTe, CZT and HgI{sub 2}. The wide band gap of TlBr (2.68 eV) permits the detectors low-noise operation at around room temperature. Our studies made an effort to fabricate pixellated TlBr detectors had sufficient detection efficiency and good charge collection efficiency. In this study, pixellated TlBr detectors were fabricated from the crystals purified by the multipass zone-refining method and grown by the horizontal traveling molten zone (TMZ) method. The TlBr detector has a continuous cathode over one crystal surface and 3x3 pixellated anodes (0.57x0.57 mm{sup 2} each) surrounded by a guard ring on the opposite surface. The electrodes were realized by vacuum evaporation of palladium through a shadow mask. Typical thickness of the detector was 2 mm. Spectrometric performance of the TlBr detectors was tested by irradiating them with {sup 241}Am (59.5 keV), {sup 57}Co (122 keV) and {sup 137}Cs (662 keV) gamma-ray sources at temperature of -20 deg. C. Energy resolutions (FWHM) were measured to be 4.0, 6.0 and 9.7 keV for 59.5, 122 and 662 keV gamma-rays, respectively.

  2. Simulated and experimental spectroscopic performance of GaAs X-ray pixel detectors

    International Nuclear Information System (INIS)

    Bisogni, M.G.; Cola, A.; Fantacci, M.E.

    2001-01-01

    In pixel detectors, the electrode geometry affects the signal shape and therefore the spectroscopic performance of the device. This effect is enhanced in semiconductors where carrier trapping is relevant. In particular, semi insulating (SI) GaAs crystals present an incomplete charge collection due to a high concentration of deep traps in the bulk. In the last few years, SI GaAs pixel detectors have been developed as soft X-ray detectors for medical imaging applications. In this paper, we present a numerical method to evaluate the local charge collection properties of pixel detectors. A bi-dimensional description has been used to represent the detector geometry. According to recent models, the active region of a reverse biased SI GaAs detector is almost neutral. Therefore, the electrostatic potential inside a full active detector has been evaluated using the Laplace equation. A finite difference method with a fixed step orthogonal mesh has been adopted. The photon interaction point has been generated with a Monte Carlo method according to the attenuation length of a monochromatic X-ray beam in GaAs. The number of photogenerated carriers for each interaction has been extracted using a gaussian distribution. The induced signal on the collecting electrode has been calculated according to the Ramo's theorem and the trapping effect has been modeled introducing electron and hole lifetimes. The noise of the charge preamplifier have been also taken into account. A comparison between simulated and experimental X-ray spectra from a 241 Am source acquired with different GaAs pixel detectors has been carried out

  3. The high dynamic range pixel array detector (HDR-PAD): Concept and design

    Energy Technology Data Exchange (ETDEWEB)

    Shanks, Katherine S.; Philipp, Hugh T.; Weiss, Joel T.; Becker, Julian; Tate, Mark W. [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Gruner, Sol M., E-mail: smg26@cornell.edu [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY 14853 (United States)

    2016-07-27

    Experiments at storage ring light sources as well as at next-generation light sources increasingly require detectors capable of high dynamic range operation, combining low-noise detection of single photons with large pixel well depth. XFEL sources in particular provide pulse intensities sufficiently high that a purely photon-counting approach is impractical. The High Dynamic Range Pixel Array Detector (HDR-PAD) project aims to provide a dynamic range extending from single-photon sensitivity to 10{sup 6} photons/pixel in a single XFEL pulse while maintaining the ability to tolerate a sustained flux of 10{sup 11} ph/s/pixel at a storage ring source. Achieving these goals involves the development of fast pixel front-end electronics as well as, in the XFEL case, leveraging the delayed charge collection due to plasma effects in the sensor. A first prototype of essential electronic components of the HDR-PAD readout ASIC, exploring different options for the pixel front-end, has been fabricated. Here, the HDR-PAD concept and preliminary design will be described.

  4. TSV last for hybrid pixel detectors: Application to particle physics and imaging experiments

    CERN Document Server

    Henry, D; Berthelot, A; Cuchet, R; Chantre, C; Campbell, M

    Hybrid pixel detectors are now widely used in particle physics experiments and at synchrotron light sources. They have also stimulated growing interest in other fields and, in particular, in medical imaging. Through the continuous pursuit of miniaturization in CMOS it has been possible to increase the functionality per pixel while maintaining or even shrinking pixel dimensions. The main constraint on the more extensive use of the technology in all fields is the cost of module building and the difficulty of covering large areas seamlessly [1]. On another hand, in the field of electronic component integration, a new approach has been developed in the last years, called 3D Integration. This concept, based on using the vertical axis for component integration, allows improving the global performance of complex systems. Thanks to this technology, the cost and the form factor of components could be decreased and the performance of the global system could be enhanced. In the field of radiation imaging detectors the a...

  5. Development and characterization of a DEPFET pixel prototype system for the ILC vertex detector

    Energy Technology Data Exchange (ETDEWEB)

    Kohrs, Robert

    2008-09-15

    For the future TeV-scale linear collider ILC (International Linear Collider) a vertex detector of unprecedented performance is needed to fully exploit its physics potential. By incorporating a field effect transistor into a fully depleted sensor substrate the DEPFET (Depleted Field Effect Transistor) sensor combines radiation detection and in-pixel amplification. For the operation at a linear collider the excellent noise performance of DEPFET pixels allows building very thin detectors with a high spatial resolution and a low power consumption. With this thesis a prototype system consisting of a 64 x 128 pixels sensor, dedicated steering and readout ASICs and a data acquisition board has been developed and successfully operated in the laboratory and under realistic conditions in beam test environments at DESY and CERN. A DEPFET matrix has been successfully read out using the on-chip zero-suppression of the readout chip CURO 2. The results of the system characterization and beam test results are presented. (orig.)

  6. Robustness of the Artificial Neural Networks Used for Clustering in the ATLAS Pixel Detector

    CERN Document Server

    The ATLAS collaboration

    2015-01-01

    A study of the robustness of the ATLAS pixel neural network clustering algorithm is presented. The sensitivity to variations to its input is evaluated. These variations are motivated by potential discrepancies between data and simulation due to uncertainties in the modelling of pixel clusters in simulation, as well as uncertainties from the detector calibration. Within reasonable variation magnitudes, the neural networks prove to be robust to most variations. The neural network used to identify pixel clusters created by multiple charged particles, is most sensitive to variations affecting the total amount of charge collected in the cluster. Modifying the read-out threshold has the biggest effect on the clustering's ability to estimate the position of the particle's intersection with the detector.

  7. Development and characterization of a DEPFET pixel prototype system for the ILC vertex detector

    International Nuclear Information System (INIS)

    Kohrs, Robert

    2008-09-01

    For the future TeV-scale linear collider ILC (International Linear Collider) a vertex detector of unprecedented performance is needed to fully exploit its physics potential. By incorporating a field effect transistor into a fully depleted sensor substrate the DEPFET (Depleted Field Effect Transistor) sensor combines radiation detection and in-pixel amplification. For the operation at a linear collider the excellent noise performance of DEPFET pixels allows building very thin detectors with a high spatial resolution and a low power consumption. With this thesis a prototype system consisting of a 64 x 128 pixels sensor, dedicated steering and readout ASICs and a data acquisition board has been developed and successfully operated in the laboratory and under realistic conditions in beam test environments at DESY and CERN. A DEPFET matrix has been successfully read out using the on-chip zero-suppression of the readout chip CURO 2. The results of the system characterization and beam test results are presented. (orig.)

  8. MCC:the Module Controller Chip for the ATLAS Pixel Detector

    Czech Academy of Sciences Publication Activity Database

    Beccherle, R.; Darbo, G.; Gagliardi, G.; Šícho, Petr

    2002-01-01

    Roč. 492, 1-2 (2002), s. 117-133 ISSN 0168-9002 R&D Projects: GA MPO RP-4210/69 Institutional research plan: CEZ:AV0Z1010920 Keywords : ASIC * radiation hardness * silicon pixel detectors * ATLAS * LHC Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.167, year: 2002

  9. Test Beam Performance Measurements for the Phase I Upgrade of the CMS Pixel Detector

    CERN Document Server

    Dragicevic, M.; Hrubec, J.; Steininger, H.; Gädda, A.; Härkönen, J.; Lampén, T.; Luukka, P.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Winkler, A.; Eerola, P.; Tuuva, T.; Baulieu, G.; Boudoul, G.; Caponetto, L.; Combaret, C.; Contardo, D.; Dupasquier, T.; Gallbit, G.; Lumb, N.; Mirabito, L.; Perries, S.; Donckt, M.Vander; Viret, S.; Bonnin, C.; Charles, L.; Gross, L.; Hosselet, J.; Tromson, D.; Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Pierschel, G.; Preuten, M.; Rauch, M.; Wlochal, M.; Aldaya, M.; Asawatangtrakuldee, C.; Beernaert, K.; Bertsche, D.; Contreras-Campana, C.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Gallo, E.; Garcia, J.Garay; Hansen, K.; Haranko, M.; Harb, A.; Hauk, J.; Keaveney, J.; Kalogeropoulos, A.; Kleinwort, C.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Pitzl, D.; Reichelt, O.; Savitskyi, M.; Schütze, P.; Sola, V.; Spannagel, S.; Walsh, R.; Zuber, A.; Biskop, H.; Buhmann, P.; Centis-Vignali, M.; Garutti, E.; Haller, J.; Hoffmann, M.; Klanner, R.; Lapsien, T.; Matysek, M.; Perieanu, A.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schwandt, J.; Sonneveld, J.; Steinbrück, G.; Vormwald, B.; Wellhausen, J.; Abbas, M.; Amstutz, C.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; Boer, W.De; Butz, E.; Casele, M.; Colombo, F.; Dierlamm, A.; Freund, B.; Hartmann, F.; Heindl, S.; Husemann, U.; Kornmeyer, A.; Kudella, S.; Muller, Th.; Simonis, H.J.; Steck, P.; Weber, M.; Weiler, Th.; Kiss, T.; Siklér, F.; Tölyhi, T.; Veszprémi, V.; Cariola, P.; Creanza, D.; Palma, M.De; Robertis, G.De; Fiore, L.; Franco, M.; Loddo, F.; Sala, G.; Silvestris, L.; Maggi, G.; My, S.; Selvaggi, G.; Albergo, S.; Cappello, G.; Costa, S.; Mattia, A.Di; Giordano, F.; Potenza, R.; Saizu, M.A.; Tricomi, A.; Tuve, C.; Focardi, E.; Dinardo, M.E.; Fiorendi, S.; Gennai, S.; Malvezzi, S.; Manzoni, R.A.; Menasce, D.; Moroni, L.; Pedrini, D.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Pozzobon, N.; Tosi, M.; Solestizi, L.Alunni; Biasini, M.; Bilei, G.M.; Cecchi, C.; Checcucci, B.; Ciangottini, D.; Fanò, L.; Gentsos, C.; Ionica, M.; Leonardi, R.; Manoni, E.; Mantovani, G.; Marconi, S.; Mariani, V.; Menichelli, M.; Modak, A.; Morozzi, A.; Moscatelli, F.; Passeri, D.; Placidi, P.; Postolache, V.; Rossi, A.; Saha, A.; Santocchia, A.; Storchi, L.; Spiga, D.; Androsov, K.; Azzurri, P.; Bagliesi, G.; Basti, A.; Boccali, T.; Borrello, L.; Bosi, F.; Castaldi, R.; Ceccanti, M.; Ciocci, M.A.; Dell'Orso, R.; Donato, S.; Fedi, G.; Giassi, A.; Grippo, M.T.; Ligabue, F.; Magazzu, G.; Mammini, P.; Mariani, F.; Mazzoni, E.; Messineo, A.; Moggi, A.; Morsani, F.; Palla, F.; Palmonari, F.; Profeti, A.; Raffaelli, F.; Ragonesi, A.; Rizzi, A.; Soldani, A.; Spagnolo, P.; Tenchini, R.; Tonelli, G.; Venturi, A.; Verdini, P.G.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bonnaud, J.; Daguin, J.; D'Auria, A.; Detraz, S.; Dondelewski, O.; Engegaard, B.; Faccio, F.; Frank, N.; Gill, K.; Honma, A.; Kornmayer, A.; Labaza, A.; Manolescu, F.; McGill, I.; Mersi, S.; Michelis, S.; Onnela, A.; Ostrega, M.; Pavis, S.; Peisert, A.; Pernot, J.F.; Petagna, P.; Postema, H.; Rapacz, K.; Sigaud, C.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Verlaat, B.; Vichoudis, P.; Zwalinski, L.; Bachmair, F.; Becker, R.; di Calafiori, D.; Casal, B.; Berger, P.; Djambazov, L.; Donega, M.; Grab, C.; Hits, D.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Arbol, P.Martinez Ruiz del; Masciovecchio, M.; Meinhard, M.; Perozzi, L.; Roeser, U.; Starodumov, A.; Tavolaro, V.; Wallny, R.; Zhu, D.; Amsler, C.; Bösiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; de Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Chen, P.H.; Dietz, C.; Fiori, F.; Grundler, U.; Hou, W.S.; Lu, R.S.; Moya, M.; Tsai, J.F.; Tzeng, Y.M.; Cussans, D.; Goldstein, J.; Grimes, M.; Newbold, D.; Hobson, P.; Reid, I.D.; Auzinger, G.; Bainbridge, R.; Dauncey, P.; Hall, G.; James, T.; Magnan, A.M.; Pesaresi, M.; Raymond, D.M.; Uchida, K.; Durkin, T.; Harder, K.; Shepherd-Themistocleous, C.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Olmedo, M.; Si, W.; Yates, B.R.; Dominguez, A.; Bartek, R.; Bentele, B.; Cumalat, J.P.; Ford, W.T.; Jensen, F.; Johnson, A.; Krohn, M.; Leontsinis, S.; Mulholland, T.; Stenson, K.; Wagner, S.R.; Apresyan, A.; Bolla, G.; Burkett, K.; Butler, J.N.; Canepa, A.; Cheung, H.W.K.; Christian, D.; Cooper, W.E.; Deptuch, G.; Derylo, G.; Gingu, C.; Grünendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Kahlid, F.; Kwan, S.; Lei, C.M.; Lipton, R.; Sá, R.Lopes De; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Schneider, B.; Sellberg, G.; Shenai, A.; Siehl, K.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Berry, D.R.; Chen, X.; Ennesser, L.; Evdokimov, A.; Gerber, C.E.; Makauda, S.; Mills, C.; Gonzalez, I.D.Sandoval; Alimena, J.; Antonelli, L.J.; Francis, B.; Hart, A.; Hill, C.S.; Parashar, N.; Stupak, J.; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D.H.; Shi, X.; Baringer, P.; Bean, A.; Khalil, S.; Kropivnitskaya, A.; Majumder, D.; Schmitz, E.; Wilson, G.; Ivanov, A.; Mendis, R.; Mitchell, T.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Acosta, J.G.; Cremaldi, L.M.; Oliveros, S.; Perera, L.; Summers, D.; Bloom, K.; Claes, D.R.; Fangmeier, C.; Suarez, R.Gonzalez; Monroy, J.; Siado, J.; Bartz, E.; Gershtein, Y.; Halkiadakis, E.; Kyriacou, S.; Lath, A.; Nash, K.; Osherson, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Norberg, S.; Vargas, J.E.Ramirez; Alyari, M.; Dolen, J.; Godshalk, A.; Harrington, C.; Iashvili, I.; Kharchilava, A.; Nguyen, D.; Parker, A.; Rappoccio, S.; Roozbahani, B.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; McDermott, K.; Mirman, N.; Rinkevicius, A.; Ryd, A.; Salvati, E.; Skinnari, L.; Soffi, L.; Tao, Z.; Thom, J.; Tucker, J.; Zientek, M.; Akgün, B.; Ecklund, K.M.; Kilpatrick, M.; Nussbaum, T.; Zabel, J.; D'Angelo, P.; Johns, W.; Rose, K.

    2017-05-30

    A new pixel detector for the CMS experiment is being built, owing to the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking while featuring a reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and comprises a low-threshold comparator. These upgrades allow the new pixel detector to sustain and improve the efficiency of the current pixel tracker at the increased requirements imposed by high luminosities and pile-up. In this paper, comprehensive test beam studies are presented which have been conducted to verify the design and to quantify the performance of the new detector assemblies in terms of tracking efficiency and spatial resolution. Under optimal conditions, the tracking efficiency has been determined to be ($99.95 \\pm 0.05$) \\%, while the intrinsic spatial resolution has been measured to be ($4.80 \\pm 0.25$) $\\mu$m and ($7.99 \\pm 0.21$...

  10. A GEANT4 based simulation for pixelated X-ray hybrid detectors

    International Nuclear Information System (INIS)

    Marinho, F.; Akiba, K.

    2015-01-01

    In this letter we present a detailed Monte Carlo approach to simulate pixelated detectors for X-ray applications. It allows us to fully characterize quantities such as interaction probability and reconstructed energy deposits according to beam energy as to evaluate energy and position resolution for comparisons with experimental results. The implementation and use of Monte Carlo truth information is also discussed

  11. Study of planar pixel sensors hardener to radiations for the upgrade of the ATLAS vertex detector

    International Nuclear Information System (INIS)

    Benoit, M.

    2011-05-01

    In this work, we present a study, using TCAD (Technology Computer-Assisted Design) simulation, of the possible methods of designing planar pixel sensors by reducing their inactive area and improving their radiation hardness for use in the Insertable B-Layer (IBL) project and for SLHC upgrade phase for the ATLAS experiment. Different physical models available have been studied to develop a coherent model of radiation damage in silicon that can be used to predict silicon pixel sensor behavior after exposure to radiation. The Multi-Guard Ring Structure, a protection structure used in pixel sensor design was studied to obtain guidelines for the reduction of inactive edges detrimental to detector operation while keeping a good sensor behavior through its lifetime in the ATLAS detector. A campaign of measurement of the sensor process parameters and electrical behavior to validate and calibrate the TCAD simulation models and results are also presented. A model for diode charge collection in highly irradiated environment was developed to explain the high charge collection observed in highly irradiated devices. A simple planar pixel sensor digitization model to be used in test beam and full detector system is detailed. It allows for easy comparison between experimental data and prediction by the various radiation damage models available. The digitizer has been validated using test beam data for unirradiated sensors and can be used to produce the first full scale simulation of the ATLAS detector with the IBL that include sensor effects such as slim edge and thinning of the sensor. (author)

  12. 18k Channels single photon counting readout circuit for hybrid pixel detector

    International Nuclear Information System (INIS)

    Maj, P.; Grybos, P.; Szczygiel, R.; Zoladz, M.; Sakumura, T.; Tsuji, Y.

    2013-01-01

    We have performed measurements of an integrated circuit named PXD18k designed for hybrid pixel semiconductor detectors used in X-ray imaging applications. The PXD18k integrated circuit, fabricated in CMOS 180 nm technology, has dimensions of 9.64 mm×20 mm and contains approximately 26 million transistors. The core of the IC is a matrix of 96×192 pixels with 100 μm×100 μm pixel size. Each pixel works in a single photon counting mode. A single pixel contains two charge sensitive amplifiers with Krummenacher feedback scheme, two shapers, two discriminators (with independent thresholds A and B) and two 16-bit ripple counters. The data are read out via eight low voltage differential signaling (LVDS) outputs with 100 Mbps rate. The power consumption is dominated by analog blocks and it is about 23 μW/pixel. The effective peaking time at the discriminator input is 30 ns and is mainly determined by the time constants of the charge sensitive amplifier (CSA). The gain is equal to 42.5 μV/e − and the equivalent noise charge is 168 e − rms (with bump-bonded silicon pixel detector). Thanks to the use of trim DACs in each pixel, the effective threshold spread at the discriminator input is only 1.79 mV. The dead time of the front end electronics for a standard setting is 172 ns (paralyzable model). In the standard readout mode (when the data collection time is separated from the time necessary to readout data from the chip) the PXD18k IC works with two energy thresholds per pixel. The PXD18k can also be operated in the continuous readout mode (with a zero dead time) where one can select the number of bits readout from each pixel to optimize the PXD18k frame rate. For example, for reading out 16 bits/pixel the frame rate is 2.7 kHz and for 4 bits/pixel it rises to 7.1 kHz.

  13. 18k Channels single photon counting readout circuit for hybrid pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Maj, P., E-mail: piotr.maj@agh.edu.pl [AGH University of Science and Technology, Department of Measurements and Electronics, Al. Mickiewicza 30, 30-059 Krakow (Poland); Grybos, P.; Szczygiel, R.; Zoladz, M. [AGH University of Science and Technology, Department of Measurements and Electronics, Al. Mickiewicza 30, 30-059 Krakow (Poland); Sakumura, T.; Tsuji, Y. [X-ray Analysis Division, Rigaku Corporation, Matsubara, Akishima, Tokyo 196-8666 (Japan)

    2013-01-01

    We have performed measurements of an integrated circuit named PXD18k designed for hybrid pixel semiconductor detectors used in X-ray imaging applications. The PXD18k integrated circuit, fabricated in CMOS 180 nm technology, has dimensions of 9.64 mm Multiplication-Sign 20 mm and contains approximately 26 million transistors. The core of the IC is a matrix of 96 Multiplication-Sign 192 pixels with 100 {mu}m Multiplication-Sign 100 {mu}m pixel size. Each pixel works in a single photon counting mode. A single pixel contains two charge sensitive amplifiers with Krummenacher feedback scheme, two shapers, two discriminators (with independent thresholds A and B) and two 16-bit ripple counters. The data are read out via eight low voltage differential signaling (LVDS) outputs with 100 Mbps rate. The power consumption is dominated by analog blocks and it is about 23 {mu}W/pixel. The effective peaking time at the discriminator input is 30 ns and is mainly determined by the time constants of the charge sensitive amplifier (CSA). The gain is equal to 42.5 {mu}V/e{sup -} and the equivalent noise charge is 168 e{sup -} rms (with bump-bonded silicon pixel detector). Thanks to the use of trim DACs in each pixel, the effective threshold spread at the discriminator input is only 1.79 mV. The dead time of the front end electronics for a standard setting is 172 ns (paralyzable model). In the standard readout mode (when the data collection time is separated from the time necessary to readout data from the chip) the PXD18k IC works with two energy thresholds per pixel. The PXD18k can also be operated in the continuous readout mode (with a zero dead time) where one can select the number of bits readout from each pixel to optimize the PXD18k frame rate. For example, for reading out 16 bits/pixel the frame rate is 2.7 kHz and for 4 bits/pixel it rises to 7.1 kHz.

  14. Fabrication and characterization of n-on-n silicon pixel detectors compatible with the Medipix2 readout chip

    Energy Technology Data Exchange (ETDEWEB)

    Zorzi, N. [ITC-irst, Divisione Microsistemi, Via Sommarive 18, I-38050 Povo (Trento) (Italy)]. E-mail: zorzi@itc.it; Bisogni, M.G. [Dipartimento di Fisica, Universita di Pisa and Sezione INFN, Via Buonarroti 2, I-56127 Pisa (Italy); Boscardin, M. [ITC-irst, Divisione Microsistemi, Via Sommarive 18, I-38050 Povo (Trento) (Italy); Dalla Betta, G.-F. [Dipartimento di Informatica e Telecomunicazioni, Universita di Trento, Via Sommarive 14, I-38050 Povo (Trento) (Italy); Gregori, P. [ITC-irst, Divisione Microsistemi, Via Sommarive 18, I-38050 Povo (Trento) (Italy); Novelli, M. [Dipartimento di Fisica, Universita di Pisa and Sezione INFN, Via Buonarroti 2, I-56127 Pisa (Italy); Piemonte, C. [ITC-irst, Divisione Microsistemi, Via Sommarive 18, I-38050 Povo (Trento) (Italy); Quattrocchi, M. [Dipartimento di Fisica, Universita di Pisa and Sezione INFN, Via Buonarroti 2, I-56127 Pisa (Italy); Ronchin, S. [ITC-irst, Divisione Microsistemi, Via Sommarive 18, I-38050 Povo (Trento) (Italy); Rosso, V. [Dipartimento di Fisica, Universita di Pisa and Sezione INFN, Via Buonarroti 2, I-56127 Pisa (Italy)

    2005-07-01

    Pixel detectors for mammographic applications have been fabricated at ITC-irst on 800 {mu}m thick silicon wafers adopting a double side n{sup +}-on-n fabrication technology. The activity aims at increasing the X-ray detection efficiency in the energy range of interest minimizing the risk of electrical discharges in hybrid systems operating at high voltages. The detectors, having a layout compatible with the Medipix2 photon counting chip, feature two different design solutions for the p-isolation between neighboring n{sup +}-pixels. We report on the characterization of the fabrication process and on preliminary results of electrical measurements on full detectors and pixel test structures. In particular, we found that the detectors can be reliably operated above the full depletion voltage regardless of the isolation design, that however, impacts the performances in terms of current-voltage characteristics, single pixel currents, inter-pixel resistances and inter-pixel capacitances.

  15. Fabrication and characterization of n-on-n silicon pixel detectors compatible with the Medipix2 readout chip

    International Nuclear Information System (INIS)

    Zorzi, N.; Bisogni, M.G.; Boscardin, M.; Dalla Betta, G.-F.; Gregori, P.; Novelli, M.; Piemonte, C.; Quattrocchi, M.; Ronchin, S.; Rosso, V.

    2005-01-01

    Pixel detectors for mammographic applications have been fabricated at ITC-irst on 800 μm thick silicon wafers adopting a double side n + -on-n fabrication technology. The activity aims at increasing the X-ray detection efficiency in the energy range of interest minimizing the risk of electrical discharges in hybrid systems operating at high voltages. The detectors, having a layout compatible with the Medipix2 photon counting chip, feature two different design solutions for the p-isolation between neighboring n + -pixels. We report on the characterization of the fabrication process and on preliminary results of electrical measurements on full detectors and pixel test structures. In particular, we found that the detectors can be reliably operated above the full depletion voltage regardless of the isolation design, that however, impacts the performances in terms of current-voltage characteristics, single pixel currents, inter-pixel resistances and inter-pixel capacitances

  16. Operational Experience of the ATLAS SemiConductor Tracker and Pixel Detector

    CERN Document Server

    Robinson, Dave; The ATLAS collaboration

    2016-01-01

    The tracking performance of the ATLAS detector relies critically on the silicon and gaseous tracking subsystems that form the ATLAS Inner Detector. Those subsystems have undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the LHC during Run2. The key status and performance metrics of the Pixel Detector and the Semi Conductor Tracker are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency are described.

  17. Study of prototypes of LFoundry active CMOS pixels sensors for the ATLAS detector

    Science.gov (United States)

    Vigani, L.; Bortoletto, D.; Ambroz, L.; Plackett, R.; Hemperek, T.; Rymaszewski, P.; Wang, T.; Krueger, H.; Hirono, T.; Caicedo Sierra, I.; Wermes, N.; Barbero, M.; Bhat, S.; Breugnon, P.; Chen, Z.; Godiot, S.; Pangaud, P.; Rozanov, A.

    2018-02-01

    Current high energy particle physics experiments at the LHC use hybrid silicon detectors, in both pixel and strip configurations, for their inner trackers. These detectors have proven to be very reliable and performant. Nevertheless, there is great interest in depleted CMOS silicon detectors, which could achieve a similar performance at lower cost of production. We present recent developments of this technology in the framework of the ATLAS CMOS demonstrator project. In particular, studies of two active sensors from LFoundry, CCPD_LF and LFCPIX, are shown.

  18. Study of prototypes of LFoundry active CMOS pixels sensors for the ATLAS detector

    CERN Document Server

    Vigani, L.; Ambroz, L.; Plackett, R.; Hemperek, T.; Rymaszewski, P.; Wang, T.; Krueger, H.; Hirono, T.; Caicedo Sierra, I.; Wermes, N.; Barbero, M.; Bhat, S.; Breugnon, P.; Chen, Z.; Godiot, S.; Pangaud, P.; Rozanov, A.

    2018-01-01

    Current high energy particle physics experiments at the LHC use hybrid silicon detectors, in both pixel and strip configurations, for their inner trackers. These detectors have proven to be very reliable and performant. Nevertheless, there is great interest in depleted CMOS silicon detectors, which could achieve a similar performance at lower cost of production. We present recent developments of this technology in the framework of the ATLAS CMOS demonstrator project. In particular, studies of two active sensors from LFoundry, CCPD_LF and LFCPIX, are shown.

  19. The CMS Pixel Detector Upgrade and R\\&D for the High Luminosity LHC

    CERN Document Server

    Viliani, Lorenzo

    2017-01-01

    The High Luminosity Large Hadron Collider (HL-LHC) at CERN is expected to collide protons at a centre-of-mass energy of 14\\,TeV and to reach an unprecedented peak instantaneous luminosity of $5 \\times 10^{34}\\,{\\rm cm}^{-2} {\\rm s}^{-1}$ with an average number of pileup events of 140. This will allow the ATLAS and CMS experiments to collect integrated luminosities of up to $3000\\,{\\rm fb}^{-1}$ during the project lifetime. To cope with this extreme scenario the CMS detector will be substantially upgraded before starting the HL-LHC, a plan known as CMS Phase-2 Upgrade. In the upgrade the entire CMS silicon pixel detector will be replaced and the new detector will feature increased radiation hardness, higher granularity and capability to handle higher data rate and longer trigger latency. In this report the Phase-2 Upgrade of the CMS silicon pixel detector will be reviewed, focusing on the features of the detector layout and on the development of new pixel devices.

  20. X-ray Imaging Using a Hybrid Photon Counting GaAs Pixel Detector

    CERN Document Server

    Schwarz, C; Göppert, R; Heijne, Erik H M; Ludwig, J; Meddeler, G; Mikulec, B; Pernigotti, E; Rogalla, M; Runge, K; Smith, K M; Snoeys, W; Söldner-Rembold, S; Watt, J

    1999-01-01

    The performance of hybrid GaAs pixel detectors as X-ray imaging sensors were investigated at room temperature. These hybrids consist of 300 mu-m thick GaAs pixel detectors, flip-chip bonded to a CMOS Single Photon Counting Chip (PCC). This chip consists of a matrix of 64 x 64 identical square pixels (170 mu-m x 170 mu-m) and covers a total area of 1.2 cm**2. The electronics in each cell comprises a preamplifier, a discriminator with a 3-bit threshold adjust and a 15-bit counter. The detector is realized by an array of Schottky diodes processed on semi-insulating LEC-GaAs bulk material. An IV-charcteristic and a detector bias voltage scan showed that the detector can be operated with voltages around 200 V. Images of various objects were taken by using a standard X-ray tube for dental diagnostics. The signal to noise ratio (SNR) was also determined. The applications of these imaging systems range from medical applications like digital mammography or dental X-ray diagnostics to non destructive material testing (...

  1. Characterisation of the NA62 GigaTracker End of Column Demonstrator Hybrid Pixel Detector

    Science.gov (United States)

    Noy, M.; Aglieri Rinella, G.; Cotta Ramusino, A.; Fiorini, M.; Jarron, P.; Kaplon, J.; Kluge, A.; Martin, E.; Morel, M.; Perktold, L.; Poltorak, K.; Riedler, P.

    2011-11-01

    The architecture and characterisation of the NA62 GigaTracker End of Column Demonstrator Hybrid Pixel Detector (HPD) are presented. This detector must perform time stamping to 200 ps (RMS) or better, provide 300 μm pitch position information and operate with a dead time of 1% or less for 800 MHz-1 GHz beam rate. The demonstrator HPD Assembly comprises a readout chip with a test column of 45 pixels, alongside other test structures, bump bonded to a p-in-n detector 200 μm in thickness. Validation of the performance of the HPD and the time-over-threshold timewalk compensation mechanism with both beam particles and a high precision laser system was performed and is presented. Confirmation of better than the required time stamping precision has been demonstrated and subsequent work on the design of the full-scale ASIC, dubbed TDCPix, is underway. An overview of the TDCPix architecure is given.

  2. Low mass hybrid pixel detectors for the high luminosity LHC upgrade

    CERN Document Server

    Gonella, Laura; Desch, Klaus

    2013-11-11

    Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are dis...

  3. Ion-ion coincidence imaging at high event rate using an in-vacuum pixel detector

    Science.gov (United States)

    Long, Jingming; Furch, Federico J.; Durá, Judith; Tremsin, Anton S.; Vallerga, John; Schulz, Claus Peter; Rouzée, Arnaud; Vrakking, Marc J. J.

    2017-07-01

    A new ion-ion coincidence imaging spectrometer based on a pixelated complementary metal-oxide-semiconductor detector has been developed for the investigation of molecular ionization and fragmentation processes in strong laser fields. Used as a part of a velocity map imaging spectrometer, the detection system is comprised of a set of microchannel plates and a Timepix detector. A fast time-to-digital converter (TDC) is used to enhance the ion time-of-flight resolution by correlating timestamps registered separately by the Timepix detector and the TDC. In addition, sub-pixel spatial resolution (principle experiment on strong field dissociative double ionization of carbon dioxide molecules (CO2), using a 400 kHz repetition rate laser system. The experimental results demonstrate that the spectrometer can detect multiple ions in coincidence, making it a valuable tool for studying the fragmentation dynamics of molecules in strong laser fields.

  4. Operational Experience and Performance with the ATLAS Pixel Detector at the Large Hadron Collider

    CERN Document Server

    Grummer, Aidan; The ATLAS collaboration

    2018-01-01

    The tracking performance of the ATLAS detector relies critically on its 4-layer Pixel Detector, that has undergone significant hardware and software upgrades to meet the challenges imposed by the higher collision energy, pileup and luminosity that are being delivered by the Large Hadron Collider, with record breaking instantaneous luminosities of 2 x 10^34 cm-2 s-1 recently surpassed. The key status and performance metrics of the ATLAS Pixel Detector are summarised, and the operational experience and requirements to ensure optimum data quality and data taking efficiency will be described, with special emphasis to radiation damage experience. In particular, radiation damage effects will be showed and signs of degradation which are visible but which are not impacting yet the tracking performance (but will): dE/dX, occupancy reduction with integrated luminosity, under-depletion effects with IBL in 2016, effects of annealing that is not insignificant for the inner-most layers. Therefore the offline software strat...

  5. Development of 3D-DDTC pixel detectors for the ATLAS upgrade

    International Nuclear Information System (INIS)

    Dalla Betta, Gian-Franco; Boscardin, Maurizio; Darbo, Giovanni; Gemme, Claudia; La Rosa, Alessandro; Pernegger, Heinz; Piemonte, Claudio; Povoli, Marco; Ronchin, Sabina; Zoboli, Andrea; Zorzi, Nicola

    2011-01-01

    We report on the development of n-on-p, 3D Double-Side Double Type Column (3D-DDTC) pixel detectors fabricated at FBK-irst (Trento, Italy) and oriented to the ATLAS upgrade. The considered fabrication technology is simpler than that required for full 3D detectors with active edge, but the detector efficiency and radiation hardness critically depend on the columnar electrode overlap and should be carefully evaluated. The first assemblies of these sensors (featuring 2, 3, or 4 columns per pixel) with the ATLAS FEI3 read-out chip have been tested in laboratory. Selected results from the electrical and functional characterization with radioactive sources are discussed here.

  6. Development of 3D-DDTC pixel detectors for the ATLAS upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Betta, Gian-Franco, E-mail: dallabe@disi.unitn.it [INFN, Sezione di Padova (Gruppo Collegato di Trento), and DISI, Universita di Trento, Via Sommarive 14, 38123 Povo di Trento (Italy); Boscardin, Maurizio [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy); Darbo, Giovanni; Gemme, Claudia [INFN, Sezione di Genova, Via Dodecaneso 33, 16146 Genova (Italy); La Rosa, Alessandro; Pernegger, Heinz [CERN-PH, CH-1211 Geneve 23 (Switzerland); Piemonte, Claudio [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy); Povoli, Marco [INFN, Sezione di Padova (Gruppo Collegato di Trento), and DISI, Universita di Trento, Via Sommarive 14, 38123 Povo di Trento (Italy); Ronchin, Sabina [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy); Zoboli, Andrea [INFN, Sezione di Padova (Gruppo Collegato di Trento), and DISI, Universita di Trento, Via Sommarive 14, 38123 Povo di Trento (Italy); Zorzi, Nicola [Fondazione Bruno Kessler (FBK-irst), Via Sommarive 18, 38123 Povo di Trento (Italy)

    2011-04-21

    We report on the development of n-on-p, 3D Double-Side Double Type Column (3D-DDTC) pixel detectors fabricated at FBK-irst (Trento, Italy) and oriented to the ATLAS upgrade. The considered fabrication technology is simpler than that required for full 3D detectors with active edge, but the detector efficiency and radiation hardness critically depend on the columnar electrode overlap and should be carefully evaluated. The first assemblies of these sensors (featuring 2, 3, or 4 columns per pixel) with the ATLAS FEI3 read-out chip have been tested in laboratory. Selected results from the electrical and functional characterization with radioactive sources are discussed here.

  7. The Belle II DEPFET pixel vertex detector. Development of a full-scale module prototype

    International Nuclear Information System (INIS)

    Lemarenko, Mikhail

    2013-11-01

    The Belle II experiment, which will start after 2015 at the SuperKEKB accelerator in Japan, will focus on the precision measurement of the CP-violation mechanism and on the search for physics beyond the Standard Model. A new detection system with an excellent spatial resolution and capable of coping with considerably increased background is required. To address this challenge, a pixel detector based on DEPFET technology has been proposed. A new all silicon integrated circuit, called Data Handling Processor (DHP), is implemented in 65 nm CMOS technology. It is designed to steer the detector and preprocess the generated data. The scope of this thesis covers DHP tests and optimization as well the development of its test environment, which is the first Full-Scale Module Prototype of the DEPFET Pixel Vertex detector.

  8. DEPFET: A silicon pixel detector for future colliders. Fundamentals, characterization and performance

    CERN Document Server

    Marinas Pardo, Carlos Manuel; Vos, Marcel Andre

    2011-01-01

    The future electron-positron colliders, either breaking the energy frontier (like ILC or CLIC) or the luminosity frontier (SuperKEKB), impose unprecedented constraints over the new generation of detectors that will be operated in those facilities. In particular, the vertex detectors must be designed for an efficient flavour tagging and excellent vertex reconstruction. To cope with these requirements, highly pixelated sensors with a fast readout, very low material budget and low power consumption must be developed. Although the combination of these factors is a substantial challenge, the DEPFET Collaboration has developed a new generation of sensors that can be operated in such a harsh environment. The DEpleted P-channel Field Effect Transistor (DEPFET) is a pixel sensor that combines detection and internal amplification at the same time. With such configuration, thin detectors with good signal-to-noise ratio and low power consumption can be produced. In this thesis, the optimization and performance of two gen...

  9. TCAD simulations of High-Voltage-CMOS Pixel structures for the CLIC vertex detector

    CERN Document Server

    Buckland, Matthew Daniel

    2016-01-01

    The requirements for precision physics and the experimental conditions at CLIC result in stringent constraints for the vertex detector. Capacitively coupled active pixel sensors with 25 μm pitch implemented in a commercial 180 nm High-Voltage CMOS (HV-CMOS) process are currently under study as a candidate technology for the CLIC vertex detector. Laboratory calibration measurements and beam tests with prototypes are complemented by detailed TCAD and electronic circuit simulations, aiming for a comprehensive understanding of the signal formation in the HV-CMOS sensors and subsequent readout stages. In this note 2D and 3D TCAD simulation results of the prototype sensor, the Capacitively Coupled Pixel Detector version three (CCPDv3), will be presented. These include the electric field distribution, leakage current, well capacitance, transient response to minimum ionising particles and charge-collection.

  10. Development of 3D-DDTC pixel detectors for the ATLAS upgrade

    CERN Document Server

    Betta, G -F Dalla; Darbo, G; Gemme, C; La Rosa, A; Pernegger, H; Piemonte, C; Povoli, M; Ronchin, S; Zoboli, A; Zorzi, N

    2011-01-01

    We report on the development of n-on-p, 3D Double-Side Double Type Column (3D-DDTC) pixel detectors fabricated at FBK-irst (Trento, Italy) and oriented to the ATLAS upgrade. The considered fabrication technology is simpler than that required for full 3D detectors with active edge, but the detector efficiency and radiation hardness critically depend on the columnar electrode overlap and should be carefully evaluated. The first assemblies of these sensors (featuring 2, 3, or 4 columns per pixel) with the ATLAS FEI3 read-out chip have been tested in laboratory. Selected results from the electrical and functional characterization with radioactive sources are here discussed.

  11. X-ray response of CdZnTe detectors grown by the vertical Bridgman technique: Energy, temperature and high flux effects

    Energy Technology Data Exchange (ETDEWEB)

    Abbene, L., E-mail: leonardo.abbene@unipa.it [Dipartimento di Fisica e Chimica (DiFC), Università di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy); Gerardi, G.; Turturici, A.A.; Raso, G. [Dipartimento di Fisica e Chimica (DiFC), Università di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy); Benassi, G. [due2lab s.r.l., Via Paolo Borsellino 2, Scandiano, Reggio Emilia 42019 (Italy); Bettelli, M. [IMEM/CNR, Parco Area delle Scienze 37/A, Parma 43100 (Italy); Zambelli, N. [due2lab s.r.l., Via Paolo Borsellino 2, Scandiano, Reggio Emilia 42019 (Italy); Zappettini, A. [IMEM/CNR, Parco Area delle Scienze 37/A, Parma 43100 (Italy); Principato, F. [Dipartimento di Fisica e Chimica (DiFC), Università di Palermo, Viale delle Scienze, Edificio 18, Palermo 90128 (Italy)

    2016-11-01

    Nowadays, CdZnTe (CZT) is one of the key materials for the development of room temperature X-ray and gamma ray detectors and great efforts have been made on both the device and the crystal growth technologies. In this work, we present the results of spectroscopic investigations on new boron oxide encapsulated vertical Bridgman (B-VB) grown CZT detectors, recently developed at IMEM-CNR Parma, Italy. Several detectors, with the same electrode layout (gold electroless contacts) and different thicknesses (1 and 2.5 mm), were realized: the cathode is a planar electrode covering the detector surface (4.1×4.1 mm{sup 2}), while the anode is a central electrode (2×2 mm{sup 2}) surrounded by a guard-ring electrode. The detectors are characterized by electron mobility-lifetime product (µ{sub e}τ{sub e}) values ranging between 0.6 and 1·10{sup −3} cm{sup 2}/V and by low leakage currents at room temperature and at high bias voltages (38 nA/cm{sup 2} at 10000 V/cm). The spectroscopic response of the detectors to monochromatic X-ray and gamma ray sources ({sup 109}Cd, {sup 241}Am and {sup 57}Co), at different temperatures and fluxes (up to 1 Mcps), was measured taking into account the mitigation of the effects of incomplete charge collection, pile-up and high flux radiation induced polarization phenomena. A custom-designed digital readout electronics, developed at DiFC of University of Palermo (Italy), able to perform a fine pulse shape and height analysis even at high fluxes, was used. At low rates (200 cps) and at room temperature (T=25 °C), the detectors exhibit an energy resolution FWHM around 4% at 59.5 keV, for comparison an energy resolution of 3% was measured with Al/CdTe/Pt detectors by using the same electronics (A250F/NF charge sensitive preamplifier, Amptek, USA; nominal ENC of 100 electrons RMS). At high rates (750 kcps), energy resolution values of 7% and 9% were measured, with throughputs of 2% and 60% respectively. No radiation polarization phenomena were

  12. Boundary scan test of Belle II pixel detector electronics

    Energy Technology Data Exchange (ETDEWEB)

    Leitl, Philipp [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)

    2015-07-01

    For the upgrade of the Vertex Detector at the Belle II experiment, DEPFET sensors will be used. These sensors need Application-Specific Integrated Circuits (ASICs) for control, readout and data processing. Because of high demands for a low material budget in the sensitive area, there is only little space left for these ASICs. Using state-of-the-art technologies like Ball Grid Array (BGA) chips, which are flip-chip mounted, the requirement of 14 ASICs on each of the 40 half ladders can be fulfilled. However, this highly integrated on-sensor ASIC solution results in a lack of physical access to the electrical connections, which is a problem for traditional testing methods. To overcome these limitations, the JTAG standard IEEE 1149.1 is used to check if the circuit is in working condition. This method provides electrical access to the boundary scan cells implemented in the ASICs. Therefore it is possible to perform connectivity tests and verify if the production of the circuit was successful.

  13. Evaluation of a hybrid photon counting pixel detector for X-ray polarimetry

    International Nuclear Information System (INIS)

    Michel, T.; Durst, J.

    2008-01-01

    It has already been shown in literature that X-ray sensitive CCDs can be used to measure the degree of linear polarization of X-rays using the effect that photoelectrons are emitted with a non-isotropic angular distribution in respect to the orientation of the electric field vector of impinging photons. Up to now hybrid semiconductor pixel detectors like the Timepix-detector have never been used for X-ray polarimetry. The main reason for this is that the pixel pitch is large compared to CCDs which results in a much smaller analyzing power. On the other hand, the active thickness of the sensor layer can be larger than in CCDs leading to an increased efficiency. Therefore hybrid photon counting pixel detectors may be used for imaging and polarimetry at higher photon energies. For irradiation with polarized X-ray photons we were able to measure an asymmetry between vertical and horizontal double hit events in neighboring pixels of the hybrid photon counting Timepix-detector at room temperature. For the specific spectrum used in our experiment an average polarization asymmetry of (0.96±0.02)% was measured. Additionally, the Timepix-detector with its spectroscopic time-over-threshold-mode was used to measure the dependence of the polarization asymmetry on energy deposition in the detector. Polarization asymmetries between 0.2% at 29 keV and 3.4% at 78 keV energy deposition were determined. The results can be reproduced with our EGS4-based Monte-Carlo simulation

  14. First images of a digital autoradiography system based on a Medipix2 hybrid silicon pixel detector.

    Science.gov (United States)

    Mettivier, Giovanni; Montesi, Maria Cristina; Russo, Paolo

    2003-06-21

    We present the first images of beta autoradiography obtained with the high-resolution hybrid pixel detector consisting of the Medipix2 single photon counting read-out chip bump-bonded to a 300 microm thick silicon pixel detector. This room temperature system has 256 x 256 square pixels of 55 microm pitch (total sensitive area of 14 x 14 mm2), with a double threshold discriminator and a 13-bit counter in each pixel. It is read out via a dedicated electronic interface and control software, also developed in the framework of the European Medipix2 Collaboration. Digital beta autoradiograms of 14C microscale standard strips (containing separate bands of increasing specific activity in the range 0.0038-32.9 kBq g(-1)) indicate system linearity down to a total background noise of 1.8 x 10(-3) counts mm(-2) s(-1). The minimum detectable activity is estimated to be 0.012 Bq for 36,000 s exposure and 0.023 Bq for 10,800 s exposure. The measured minimum detection threshold is less than 1600 electrons (equivalent to about 6 keV Si). This real-time system for beta autoradiography offers lower pixel pitch and higher sensitive area than the previous Medipix1-based system. It has a 14C sensitivity better than that of micro channel plate based systems, which, however, shows higher spatial resolution and sensitive area.

  15. Finite-element simulations of coupling capacitances in capacitively coupled pixel detectors

    CERN Document Server

    AUTHOR|(SzGeCERN)755510

    2017-01-01

    Capacitively coupled hybrid silicon pixel-detector assemblies are under study for the vertex detector at the proposed future CLIC linear electron-positron collider. The assemblies consist of active CCPDv3 sensors, with 25 μm pixel pitch implemented in a 180 nm High- Voltage CMOS process, which are glued to the CLICpix readout ASIC, with the same pixel pitch and processed in a commercial 65 nm CMOS technology. The signal created in the silicon bulk of the active sensors passes a two-stage amplifier, in each pixel, and gets transferred as a voltage pulse to metal pads facing the readout chip (ROC). The coupling of the signal to the metal pads on the ROC side proceeds through the capacitors formed between the two chips by a thin layer of epoxy glue. The coupling strength and the amount of unwanted cross coupling to neighbouring pixels depends critically on the uniformity of the glue layer, its thickness and on the alignment precision during the flip-chip assembly process. Finite-element calculations of the coup...

  16. The power supply system for the DEPFET pixel detector at BELLE II

    International Nuclear Information System (INIS)

    Rummel, Stefan

    2013-01-01

    The upgrade of the KEKB accelerator towards 8×10 35 cm −2 s −1 poses several challenges for the BELLE II detector. Especially the innermost detector will be faced with a significant radiation of several MRad per year as well as a high hit density. To cope with this a silicon pixel detector will be used for the inner layers of the silicon tracker. The pixel detector (PXD) consists of two layers of DEPFET active pixel sensors. The DEPFET technology has an unique set of advantages like low power dissipation in the active area, flexible device size, radiation hardness and a thinning procedure allowing to adjust the thickness of the device over a wide range. The two layers close to the interaction point together with a low material budget will improve the IP resolution by a factor of 2 compared to the previous installed silicon detector. In addition silicon stand-alone pattern recognition will be possible together with the four layers of double sided strip detectors (DSSD) of the strip detector. The PXD detector system consists of the DEPFET modules with integrated readout chips, the data handling hybrid receiving the data and sending them to compute nodes performing an online pattern recognition. Moreover the power supply system provides the supply voltages for the DEPFET from a position outside of the detector. The power distribution is designed to provide low output impedance over all frequencies and transient response with appropriate overshoots. The PXD pose several challenges to the power distribution system—number of voltages, tight requirements on regulation and noise. -- Highlights: ► The KEKB accelerator receive a luminosity upgrade towards 8×10 35 cm −2 s −1 . ► A two layer pixel detector based on the DEPFET technology will be installed. ► An improvement of a factor of 2 in. impact parameter resolution is expected. ► The 34 A dedicated power supply system for the detector is under development which aims for low noise, low output impedance

  17. Development of the MCM-D technique for pixel detector modules

    CERN Document Server

    Grah, Christian

    2005-01-01

    This thesis treats a copper--polymer based thin film technology, the MCM-D technique and its application when building hybrid pixel detector modules. The ATLAS experiment at the LHC will be equipped with a pixel detector system. The basic mechanical units of the pixel detector are multi chip modules. The main components of these modules are: 16 electronic chips, a controller chip and a large sensor tile, featuring more than 46000 sensor cells. MCM-D is a superior technique to build the necessary signal bus system and the power distribution system directly on the active sensor tile. In collaboration with the Fraunhofer Institute for Reliability and Microintegration, IZM, the thin film process is reviewed and enhanced. The multi layer system was designed and optimized for the interconnection system as well as for the 46000 pixel contacts. Laboratory measurements on prototypes prove that complex routing schemes for geometrically optimized single chips are suitable and have negligible influence on the front--end ...

  18. Testbeam and laboratory test results of irradiated 3D CMS pixel detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bubna, Mayur [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Purdue University, School of Electrical and Computer Engineering, West Lafayette, IN 47907-1396 (United States); Alagoz, Enver, E-mail: enver.alagoz@cern.ch [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Cervantes, Mayra; Krzywda, Alex; Arndt, Kirk [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Obertino, Margherita; Solano, Ada [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, 10125 Torino (Italy); Dalla Betta, Gian-Franco [INFN Padova (Gruppo Collegato di Trento) (Italy); Dipartimento di Ingegneria e Scienzadella Informazione, Universitá di Trento, I-38123 Povo di Trento (Italy); Menace, Dario; Moroni, Luigi [Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca (Italy); Universitá degli Studi di Milano Bicocca, 20126 Milano (Italy); Uplegger, Lorenzo; Rivera, Ryan [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); Osipenkov, Ilya [Texas A and M University, Department of Physics, College Station, TX 77843-4242 (United States); Andresen, Jeff [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); Bolla, Gino; Bortoletto, Daniela [Purdue University, Department of Physics, West Lafayette, IN 47907-1396 (United States); Boscardin, Maurizio [Centro per i Materiali e i Microsistemi Fondazione Bruno Kessler (FBK), Trento, I-38123 Povo di Trento (Italy); Marie Brom, Jean [Strasbourg IPHC, Institut Pluriedisciplinaire Hubert Curien, F-67037 Strasbourg Cedex (France); Brosius, Richard [State University of New York at Buffalo (SUNY), Department of Physics, Buffalo, NY 14260-1500 (United States); Chramowicz, John [Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States); and others

    2013-12-21

    The CMS silicon pixel detector is the tracking device closest to the LHC p–p collisions, which precisely reconstructs the charged particle trajectories. The planar technology used in the current innermost layer of the pixel detector will reach the design limit for radiation hardness at the end of Phase I upgrade and will need to be replaced before the Phase II upgrade in 2020. Due to its unprecedented performance in harsh radiation environments, 3D silicon technology is under consideration as a possible replacement of planar technology for the High Luminosity-LHC or HL-LHC. 3D silicon detectors are fabricated by the Deep Reactive-Ion-Etching (DRIE) technique which allows p- and n-type electrodes to be processed through the silicon substrate as opposed to being implanted through the silicon surface. The 3D CMS pixel devices presented in this paper were processed at FBK. They were bump bonded to the current CMS pixel readout chip, tested in the laboratory, and testbeams carried out at FNAL with the proton beam of 120 GeV/c. In this paper we present the laboratory and beam test results for the irradiated 3D CMS pixel devices. -- Highlights: •Pre-irradiation and post-irradiation electrical properties of 3D sensors and 3D diodes from various FBK production batches were measured and analyzed. •I–T measurements of gamma irradiated diodes were analyzed to understand leakage current generation mechanism in 3D diodes. •Laboratory measurements: signal to noise ratio and charge collection efficiency of 3D sensors before and after irradiation. •Testbeam measurements: pre- and post-irradiation pixel cell efficiency and position resolution of 3D sensors.

  19. Radiation Damage Observations in the ATLAS Pixel Detector Using the High Voltage Delivery System

    CERN Document Server

    Toms, K

    2011-01-01

    We describe the implementation of radiation damage monitoring using leakage current measurement of the silicon pixel sensors provided by the circuits of the ATLAS Pixel Detector high voltage delivery (HVPP4) system. The dependence of the leakage current upon the integrated luminosity for several temperature scenarios is presented. Based on the analysis we have determined the sensitivity specifications for a Current Measurement System. The status of the system and the first measurement of the radiation damage corresponding to 2--4 fb$^{-1}$ of integrated luminosity are presented, as well as the comparison with the theoretical model.

  20. Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00371978; Gößling, Claus; Pernegger, Heinz

    The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ...

  1. Imaging properties of small-pixel spectroscopic x-ray detectors based on cadmium telluride sensors

    International Nuclear Information System (INIS)

    Koenig, Thomas; Schulze, Julia; Zuber, Marcus; Rink, Kristian; Oelfke, Uwe; Butzer, Jochen; Hamann, Elias; Cecilia, Angelica; Zwerger, Andreas; Fauler, Alex; Fiederle, Michael

    2012-01-01

    Spectroscopic x-ray imaging by means of photon counting detectors has received growing interest during the past years. Critical to the image quality of such devices is their pixel pitch and the sensor material employed. This paper describes the imaging properties of Medipix2 MXR multi-chip assemblies bump bonded to 1 mm thick CdTe sensors. Two systems were investigated with pixel pitches of 110 and 165 μm, which are in the order of the mean free path lengths of the characteristic x-rays produced in their sensors. Peak widths were found to be almost constant across the energy range of 10 to 60 keV, with values of 2.3 and 2.2 keV (FWHM) for the two pixel pitches. The average number of pixels responding to a single incoming photon are about 1.85 and 1.45 at 60 keV, amounting to detective quantum efficiencies of 0.77 and 0.84 at a spatial frequency of zero. Energy selective CT acquisitions are presented, and the two pixel pitches' abilities to discriminate between iodine and gadolinium contrast agents are examined. It is shown that the choice of the pixel pitch translates into a minimum contrast agent concentration for which material discrimination is still possible. We finally investigate saturation effects at high x-ray fluxes and conclude with the finding that higher maximum count rates come at the cost of a reduced energy resolution. (paper)

  2. Detector Sampling of Optical/IR Spectra: How Many Pixels per FWHM?

    Science.gov (United States)

    Robertson, J. Gordon

    2017-08-01

    Most optical and IR spectra are now acquired using detectors with finite-width pixels in a square array. Each pixel records the received intensity integrated over its own area, and pixels are separated by the array pitch. This paper examines the effects of such pixellation, using computed simulations to illustrate the effects which most concern the astronomer end-user. It is shown that coarse sampling increases the random noise errors in wavelength by typically 10-20 % at 2 pixels per Full Width at Half Maximum, but with wide variation depending on the functional form of the instrumental Line Spread Function (i.e. the instrumental response to a monochromatic input) and on the pixel phase. If line widths are determined, they are even more strongly affected at low sampling frequencies. However, the noise in fitted peak amplitudes is minimally affected by pixellation, with increases less than about 5%. Pixellation has a substantial but complex effect on the ability to see a relative minimum between two closely spaced peaks (or relative maximum between two absorption lines). The consistent scale of resolving power presented by Robertson to overcome the inadequacy of the Full Width at Half Maximum as a resolution measure is here extended to cover pixellated spectra. The systematic bias errors in wavelength introduced by pixellation, independent of signal/noise ratio, are examined. While they may be negligible for smooth well-sampled symmetric Line Spread Functions, they are very sensitive to asymmetry and high spatial frequency sub-structure. The Modulation Transfer Function for sampled data is shown to give a useful indication of the extent of improperly sampled signal in an Line Spread Function. The common maxim that 2 pixels per Full Width at Half Maximum is the Nyquist limit is incorrect and most Line Spread Functions will exhibit some aliasing at this sample frequency. While 2 pixels per Full Width at Half Maximum is nevertheless often an acceptable minimum for

  3. Post-growth annealing of Bridgman-grown CdZnTe and CdMnTe crystals for room-temperature nuclear radiation detectors

    International Nuclear Information System (INIS)

    Egarievwe, Stephen U.; Yang, Ge; Egarievwe, Alexander A.; Okwechime, Ifechukwude O.; Gray, Justin; Hales, Zaveon M.; Hossain, Anwar; Camarda, Giuseppe S.; Bolotnikov, Aleksey E.; James, Ralph B.

    2015-01-01

    Bridgman-grown cadmium zinc telluride (CdZnTe or CZT) and cadmium manganese telluride (CdMnTe or CMT) crystals often have Te inclusions that limit their performances as X-ray- and gamma-ray-detectors. We present here the results of post-growth thermal annealing aimed at reducing and eliminating Te inclusions in them. In a 2D analysis, we observed that the sizes of the Te inclusions declined to 92% during a 60-h annealing of CZT at 510 °C under Cd vapor. Further, tellurium inclusions were eliminated completely in CMT samples annealed at 570 °C in Cd vapor for 26 h, whilst their electrical resistivity fell by an order of 10 2 . During the temperature-gradient annealing of CMT at 730 °C and an 18 °C/cm temperature gradient for 18 h in a vacuum of 10 −5 mbar, we observed the diffusion of Te from the sample, so causing a reduction in size of the Te inclusions. For CZT samples annealed at 700 °C in a 10 °C/cm temperature gradient, we observed the migration of Te inclusions from a low-temperature region to a high one at 0.022 μm/s. During the temperature-gradient annealing of CZT in a vacuum of 10 −5 mbar at 570 °C and 30 °C/cm for 18 h, some Te inclusions moved toward the high-temperature side of the wafer, while other inclusions of the same size, i.e., 10 µm in diameter, remained in the same position. These results show that the migration, diffusion, and reaction of Te with Cd in the matrix of CZT- and CMT-wafers are complex phenomena that depend on the conditions in local regions, such as composition and structure, as well as on the annealing conditions

  4. Analysis of 3D stacked fully functional CMOS Active Pixel Sensor detectors

    International Nuclear Information System (INIS)

    Passeri, D; Servoli, L; Meroli, S

    2009-01-01

    The IC technology trend is to move from 3D flexible configurations (package on package, stacked dies) to real 3D ICs. This is mainly due to i) the increased electrical performances and ii) the cost of 3D integration which may be cheaper than to keep shrinking 2D circuits. Perspective advantages for particle tracking and vertex detectors applications in High Energy Physics can be envisaged: in this work, we will focus on the capabilities of the state-of-the-art vertical scale integration technologies, allowing for the fabrication of very compact, fully functional, multiple layers CMOS Active Pixel Sensor (APS) detectors. The main idea is to exploit the features of the 3D technologies for the fabrication of a ''stack'' of very thin and precisely aligned CMOS APS layers, leading to a single, integrated, multi-layers pixel sensor. The adoption of multiple-layers single detectors can dramatically reduce the mass of conventional, separated detectors (thus reducing multiple scattering issues), at the same time allowing for very precise measurements of particle trajectory and momentum. As a proof of concept, an extensive device and circuit simulation activity has been carried out, aiming at evaluate the suitability of such a kind of CMOS active pixel layers for particle tracking purposes.

  5. Low mass hybrid pixel detectors for the high luminosity LHC upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Gonella, Laura

    2013-10-15

    Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are discussed using the upgrades of the ATLAS pixel detector as a case study.

  6. Low mass hybrid pixel detectors for the high luminosity LHC upgrade

    International Nuclear Information System (INIS)

    Gonella, Laura

    2013-10-01

    Reducing material in silicon trackers is of major importance for a good overall detector performance, and poses severe challenges to the design of the tracking system. To match the low mass constraints for trackers in High Energy Physics experiments at high luminosity, dedicated technological developments are required. This dissertation presents three technologies to design low mass hybrid pixel detectors for the high luminosity upgrades of the LHC. The work targets specifically the reduction of the material from the detector services and modules, with novel powering schemes, flip chip and interconnection technologies. A serial powering scheme is prototyped, featuring a new regulator concept, a control and protection element, and AC-coupled data transmission. A modified flip chip technology is developed for thin, large area Front-End chips, and a via last Through Silicon Via process is demonstrated on existing pixel modules. These technologies, their developments, and the achievable material reduction are discussed using the upgrades of the ATLAS pixel detector as a case study.

  7. Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Gallrapp, Christian

    2015-07-01

    The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ATLAS Pixel Detector as well as for applications in the ATLAS Experiment at HL-LHC conditions. The sensors considered in this work include various designs based on silicon and diamond as sensor material. The investigated designs include a planar silicon pixel design currently used in the ATLAS Experiment as well as a 3D pixel design which uses electrodes penetrating the entire sensor material. The diamond designs implement electrodes similar to the design used by the planar technology with diamond sensors made out of single- and poly-crystalline material. To investigate the sensor properties characterization tests are performed before and after irradiation with protons or neutrons. The measurements are used to determine the interaction between the read-out electronics and the sensors to ensure the signal transfer after irradiation. Further tests focus on the sensor performance itself which includes the analysis of the leakage current behavior and the charge

  8. Studies on irradiated pixel detectors for the ATLAS IBL and HL-LHC upgrade

    International Nuclear Information System (INIS)

    Gallrapp, Christian

    2015-01-01

    The constant demand for higher luminosity in high energy physics is the reason for the continuous effort to adapt the accelerators and the experiments. The upgrade program for the experiments and the accelerators at CERN already includes several expansion stages of the Large Hadron Collider (LHC) which will increase the luminosity and the energy of the accelerator. Simultaneously the LHC experiments prepare the individual sub-detectors for the increasing demands in the coming years. Especially the tracking detectors have to cope with fluence levels unprecedented for high energy physics experiments. Correspondingly to the fluence increases the impact of the radiation damage which reduces the life time of the detectors by decreasing the detector performance and efficiency. To cope with this effect new and more radiation hard detector concepts become necessary to extend the life time. This work concentrates on the impact of radiation damage on the pixel sensor technologies to be used in the next upgrade of the ATLAS Pixel Detector as well as for applications in the ATLAS Experiment at HL-LHC conditions. The sensors considered in this work include various designs based on silicon and diamond as sensor material. The investigated designs include a planar silicon pixel design currently used in the ATLAS Experiment as well as a 3D pixel design which uses electrodes penetrating the entire sensor material. The diamond designs implement electrodes similar to the design used by the planar technology with diamond sensors made out of single- and poly-crystalline material. To investigate the sensor properties characterization tests are performed before and after irradiation with protons or neutrons. The measurements are used to determine the interaction between the read-out electronics and the sensors to ensure the signal transfer after irradiation. Further tests focus on the sensor performance itself which includes the analysis of the leakage current behavior and the charge

  9. Vectors and submicron precision: redundancy and 3D stacking in silicon pixel detectors

    CERN Document Server

    Heijne, E H M; Wong, W; Idarraga, J; Visser, J; Jakubek, J; Leroy, C; Turecek, D; Visschers, J; Pospisil, S; Ballabriga, R; Vykydal, Z; Vermeulen, J; Plackett, R; Heijne, E H M; Llopart, X; Boltje, D; Campbell, M

    2010-01-01

    Measurements are shown of GeV pions and muons in two 300 mu m thick, Si Medipix pixel detector assemblies that are stacked on top of each other, with a 25 mu m thick brass foil in between. In such a radiation imaging semiconductor matrix with a large number of pixels along the particle trail, one can determine local space vectors for the particle trajectory instead of points. This improves pattern recognition and track reconstruction, especially in a crowded environment. Stacking of sensor planes is essential for resolving directional ambiguities. Signal charge sharing can be employed for measuring positions with submicron precision. In the measurements one notices accompanying `delta' electrons that emerge outside the particle trail, far beyond the boundaries of the 55 mu m pixel cells. The frequency of such corrupted position measurements is similar to one per 2.5mm of traversed Si.

  10. Modeling Radiation Damage Effects in 3D Pixel Digitization for the ATLAS Detector

    CERN Document Server

    Giugliarelli, Gilberto; The ATLAS collaboration

    2018-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS experiment. They constitute the part of ATLAS closest to the interaction point and for this reason they will be exposed – over their lifetime – to a significant amount of radiation: prior to the HL-LHC, the innermost layers will receive a fluence of 10^15 neq/cm2 and their HL–LHC upgrades will have to cope with an order of magnitude higher fluence integrated over their lifetimes. This poster presents the details of a new digitization model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS Detector.

  11. Charge-sensitive poly-silicon TFT amplifiers for a-Si:H pixel particle detectors

    International Nuclear Information System (INIS)

    Cho, G.; Perez-Mendez, V.; Hack, M.; Lewis, A.

    1992-04-01

    Prototype charge-sensitive poly-Si TFT amplifiers have been made for the amplification of signals (from an a-Si:H pixel diode used as an ionizing particle detector). They consist of a charge-sensitive gain stage, a voltage gain stage and a source follower output stage. The gain-bandwidth product of the amplifier is ∼ 300 MHz. When the amplifier is connected to a pixel detector of 0.2 pF, it gives a charge-to-voltage gain of ∼ 0.02 mV/electrons with a pulse rise time less than 100 nsec. An equivalent noise charge of the front-end TFT is ∼ 1000 electrons for a shaping time of 1 μsec

  12. Optimization of ADC transfer curves for the Belle II pixel detector

    Energy Technology Data Exchange (ETDEWEB)

    Haidl, Jakob; Mueller, Felix; Moser, Hans-Guenther; Kiesling, Christian; Valentan, Manfred [Max-Planck-Institut fuer Physik, Muenchen (Germany); Koffmane, Christian [Halbleiterlabor der Max-Planck-Gesellschaft, Muenchen (Germany); Collaboration: Belle II-Collaboration

    2016-07-01

    The Super-KEKB accelerator at the KEK high energy research center in Tsukuba in Japan will provide a 40 times higher luminosity. To cope with this high luminosity the Belle detector is improved to Belle II, which includes the integration of a two layer DEPFET pixel detector (PXD) resulting in a higher vertex resolution. The task of the read-out electronics is to process the high data rate of the PXD. To fulfill these requirements three different types of ASICs were designed. The foremost of them called Drain Current Digitizer (DCD) converts the drain currents of the DEPFET pixel sensors into digital code. Since the PXD will be equipped with 160 DCDs automatic testing of the chips is needed. Analog to digital transfer curves are an appropriate tool for error recognition and optimization of the digitization process within the DCD. An overview of measurements and optimization strategies is presented.

  13. Tests of UFXC32k chip with CdTe pixel detector

    Science.gov (United States)

    Maj, P.; Taguchi, T.; Nakaye, Y.

    2018-02-01

    The paper presents the performance of the UFXC32K—a hybrid pixel detector readout chip working with CdTe detectors. The UFXC32K has a pixel pitch of 75 μm and can cope with both input signal polarities. This functionality allows operating with widely used silicon sensors collecting holes and CdTe sensors collecting electrons. This article describes the chip focusing on solving the issues connected to high-Z sensor material, namely high leakage currents, slow charge collection time and thick material resulting in increased charge-sharring effects. The measurements were conducted with higher X-ray energies including 17.4 keV from molybdenum. Conclusions drawn inside the paper show the UFXC32K's usability for CdTe sensors in high X-ray energy applications.

  14. Test-beam activities and results for the ATLAS ITk pixel detector

    Science.gov (United States)

    Bisanz, T.

    2017-12-01

    The Phase-II upgrade of the LHC aims at an increase of the instantaneous luminosity up to about 5×1034 cm-2 s-1. To cope with the resulting challenges the current Inner Detector will be replaced by an all-silicon Inner Tracker (ITk) system. The Pixel Detector will have to deal with occupancies of about 300 hits/FE/s as well as a fluence of around 2×1016 neq cm-2. Various sensor layouts are under development, aiming at providing a high performance, cost effective pixel instrumentation to cover an active area of about 10 m2. These range from thin planar silicon, 3D silicon, to active CMOS sensors. After extensive characterization of the sensors in the lab, their charge collection properties and hit efficiency are measured in common testbeam campaigns, which provide valuable feedback for improvements of the layout. Testbeam measurements of the final prototypes will be used for the decision of which sensor types will be installed in ITk. The setups used in the ITk Pixel testbeam campaigns will be presented, including the common track reconstruction and analysis software. Results from the latest measurements will be shown, highlighting some of the developments and challenges for the ITk Pixel sensors.

  15. Firmware development and testing of the ATLAS Pixel Detector / IBL ROD card

    International Nuclear Information System (INIS)

    Gabrielli, A.; Balbi, G.; Falchieri, D.; Lama, L.; Travaglini, R.; Backhaus, M.; Bindi, M.; Chen, S.P.; Hauck, S.; Hsu, S.C.; Flick, T.; Wensing, M.; Kretz, M.; Kugel, A.

    2015-01-01

    The ATLAS Experiment is reworking and upgrading systems during the current LHC shut down. In particular, the Pixel detector has inserted an additional inner layer called the Insertable B-Layer (IBL). The Readout-Driver card (ROD), the Back-of-Crate card (BOC), and the S-Link together form the essential frontend data path of the IBL's off-detector DAQ system. The strategy for IBL ROD firmware development was three-fold: keeping as much of the Pixel ROD datapath firmware logic as possible, employing a complete new scheme of steering and calibration firmware, and designing the overall system to prepare for a future unified code version integrating IBL and Pixel layers. Essential features such as data formatting, frontend-specific error handling, and calibration are added to the ROD data path. An IBL DAQ test bench using a realistic front-end chip model was created to serve as an initial framework for full offline electronic system simulation. In this document, major firmware achievements concerning the IBL ROD data path implementation, test on the test bench and ROD prototypes, will be reported. Recent Pixel collaboration efforts focus on finalizing hardware and firmware tests for the IBL. The plan is to approach a complete IBL DAQ hardware-software installation by the end of 2014

  16. A neural network for locating the primary vertex in a pixel detector

    International Nuclear Information System (INIS)

    Kantowski, R.; Marzban, C.

    1995-01-01

    Using simulated collider data for p+p→2Jets interactions in a two-barrel pixel detector, a neural network is trained to construct the coordinate of the primary vertex to a high degree of accuracy. Three other estimates of this coordinate are also considered and compared to that of the neural network. It is shown that the network can match the best of the traditional estimates. ((orig.))

  17. Study of a Level-3 Tau Trigger with the Pixel Detector

    CERN Document Server

    Kotlinski, Danek; Nikitenko, Alexander

    2001-01-01

    We present a Monte Carlo study of the performance of a Level-3 Tau trigger based on the Pixel Detector data. The trigger is designed to select of the Higgs bosons decaying into two tau leptons with tau jet(s) in the final state. The proposed trigger is particularly useful as it operates at an early stage of the CMS High Level Trigger system. The performance of the trigger is studied for the most difficult case of high luminosity LHC scenario.

  18. Monte Carlo simulation for pixel detectors: a feasibility study for X radiation applications

    International Nuclear Information System (INIS)

    Marinho, F.; Akiba, K.

    2014-01-01

    In this paper we analyze the feasibility of a Monte Carlo simulation for the description of pixel semiconductor detectors as a tool for research and development of such devices and their applications for X-rays. We present as a result the technical aspects and main characteristics of a set of algorithms recently developed which allows one to estimate the energy spectrum and cluster classification. (author)

  19. Analysis of painted arts by energy sensitive radiographic techniques with the Pixel Detector Timepix

    Czech Academy of Sciences Publication Activity Database

    Žemlička, J.; Jakůbek, J.; Kroupa, M.; Hradil, David; Hradilová, J.; Mislerová, H.

    2011-01-01

    Roč. 6, - (2011), C01066/1-C01066/7 ISSN 1748-0221 R&D Projects: GA MŠk(CZ) LC06041 Institutional research plan: CEZ:AV0Z40320502 Keywords : inspection with x-rays * pixelated detectors and associated VLSI electronics * X-ray fluorescence (XRF) systems * X-ray radiography and digital radiography (DR) Subject RIV: CA - Inorganic Chemistry Impact factor: 1.869, year: 2011

  20. Development of high data readout rate pixel module and detector hybridization at Fermilab

    International Nuclear Information System (INIS)

    Zimmermann, Sergio

    2001-01-01

    This paper describes the baseline design and a variation of the pixel module to handle the data rate required for the BTeV experiment at Fermilab. The present prototype has shown good electrical performance characteristics. Indium bump bonding is proven to be capable of successful fabrication at 50 micron pitch on real detectors. For solder bumps at 50 micron pitch, much better results have been obtained with the fluxless PADS processed detectors. The results are adequate for our needs and our tests have validated it as a viable technology