A pixel design for X-ray imaging with CdTe sensors

International Nuclear Information System (INIS)

Lambropoulos, C.P.; Zervakis, E.G.; Loukas, D.

2008-01-01

A readout architecture appropriate for X-ray Imaging using charge integration has been designed. Each pixel consists of a capacitive transimpedance amplifier, a sample and hold circuit a comparator and an 8 bit DRAM. Pixel level A/D conversion and local storage of the digitized signal is performed. The target sensors are 100μm x 100 μm CdTe pixel detectors and integration time of 1ms or less can be achieved. Special measures have been taken to minimize the gain fixed pattern noise and the reset noise, while purely digital correlation double sampling can be performed. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

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

Improving Land Use/Land Cover Classification by Integrating Pixel Unmixing and Decision Tree Methods

Directory of Open Access Journals (Sweden)

Chao Yang

2017-11-01

Full Text Available Decision tree classification is one of the most efficient methods for obtaining land use/land cover (LULC information from remotely sensed imageries. However, traditional decision tree classification methods cannot effectively eliminate the influence of mixed pixels. This study aimed to integrate pixel unmixing and decision tree to improve LULC classification by removing mixed pixel influence. The abundance and minimum noise fraction (MNF results that were obtained from mixed pixel decomposition were added to decision tree multi-features using a three-dimensional (3D Terrain model, which was created using an image fusion digital elevation model (DEM, to select training samples (ROIs, and improve ROI separability. A Landsat-8 OLI image of the Yunlong Reservoir Basin in Kunming was used to test this proposed method. Study results showed that the Kappa coefficient and the overall accuracy of integrated pixel unmixing and decision tree method increased by 0.093% and 10%, respectively, as compared with the original decision tree method. This proposed method could effectively eliminate the influence of mixed pixels and improve the accuracy in complex LULC classifications.

Absolute gain calibration system for the 349-pixel imaging element of the tactic telescope array

International Nuclear Information System (INIS)

Tickoo, A.K.; Dhar, V.K.; Venugopal, K.; Kaul, S.K.; Koul, R.; Bhatt, N.; Goyal, H.C.; Bhat, C.L.

2001-01-01

The imaging Element of the 4-element TACTIC telescope array has been in operation at Mt. Abu since 1997, for carrying detailed investigations of gamma-ray sources in the TeV energy range. In order to characterize the progenitor particle (Gamma-ray/cosmic-ray), a relative gain calibration system, based on a high intensity LED, has been in operation. However, for calorimetric purposes, an absolute gain calibration system is necessary and has been developed for an on-line calibration of 4 out of 349-pixels of its imaging camera, using 241 Am based light pulsers. The details of the experimental set-up and the results obtained so far are presented in this paper. (author)

Integrated Lens Antennas for Multi-Pixel Receivers

Science.gov (United States)

Lee, Choonsup; Chattopadhyay, Goutam

2011-01-01

Future astrophysics and planetary experiments are expected to require large focal plane arrays with thousands of detectors. Feedhorns have excellent performance, but their mass, size, fabrication challenges, and expense become prohibitive for very large focal plane arrays. Most planar antenna designs produce broad beam patterns, and therefore require additional elements for efficient coupling to the telescope optics, such as substrate lenses or micromachined horns. An antenna array with integrated silicon microlenses that can be fabricated photolithographically effectively addresses these issues. This approach eliminates manual assembly of arrays of lenses and reduces assembly errors and tolerances. Moreover, an antenna array without metallic horns will reduce mass of any planetary instrument significantly. The design has a monolithic array of lens-coupled, leaky-wave antennas operating in the millimeter- and submillimeter-wave frequencies. Electromagnetic simulations show that the electromagnetic fields in such lens-coupled antennas are mostly confined in approximately 12 15 . This means that one needs to design a small-angle sector lens that is much easier to fabricate using standard lithographic techniques, instead of a full hyper-hemispherical lens. Moreover, this small-angle sector lens can be easily integrated with the antennas in an array for multi-pixel imager and receiver implementation. The leaky antenna is designed using double-slot irises and fed with TE10 waveguide mode. The lens implementation starts with a silicon substrate. Photoresist with appropriate thickness (optimized for the lens size) is spun on the substrate and then reflowed to get the desired lens structure. An antenna array integrated with individual lenses for higher directivity and excellent beam profile will go a long way in realizing multi-pixel arrays and imagers. This technology will enable a new generation of compact, low-mass, and highly efficient antenna arrays for use in multi-pixel

Multi-parameter Nonlinear Gain Correction of X-ray Transition Edge Sensors for the X-ray Integral Field Unit

Science.gov (United States)

Cucchetti, E.; Eckart, M. E.; Peille, P.; Porter, F. S.; Pajot, F.; Pointecouteau, E.

2018-04-01

With its array of 3840 Transition Edge Sensors (TESs), the Athena X-ray Integral Field Unit (X-IFU) will provide spatially resolved high-resolution spectroscopy (2.5 eV up to 7 keV) from 0.2 to 12 keV, with an absolute energy scale accuracy of 0.4 eV. Slight changes in the TES operating environment can cause significant variations in its energy response function, which may result in systematic errors in the absolute energy scale. We plan to monitor such changes at pixel level via onboard X-ray calibration sources and correct the energy scale accordingly using a linear or quadratic interpolation of gain curves obtained during ground calibration. However, this may not be sufficient to meet the 0.4 eV accuracy required for the X-IFU. In this contribution, we introduce a new two-parameter gain correction technique, based on both the pulse-height estimate of a fiducial line and the baseline value of the pixels. Using gain functions that simulate ground calibration data, we show that this technique can accurately correct deviations in detector gain due to changes in TES operating conditions such as heat sink temperature, bias voltage, thermal radiation loading and linear amplifier gain. We also address potential optimisations of the onboard calibration source and compare the performance of this new technique with those previously used.

Symbol recognition via statistical integration of pixel-level constraint histograms: a new descriptor.

Science.gov (United States)

Yang, Su

2005-02-01

A new descriptor for symbol recognition is proposed. 1) A histogram is constructed for every pixel to figure out the distribution of the constraints among the other pixels. 2) All the histograms are statistically integrated to form a feature vector with fixed dimension. The robustness and invariance were experimentally confirmed.

Application-specific architectures of CMOS monolithic active pixel sensors

Energy Technology Data Exchange (ETDEWEB)

Szelezniak, Michal [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]. E-mail: michal.szelezniak@ires.in2p3.fr; Besson, Auguste [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Claus, Gilles; Colledani, Claude; [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Degerli, Yavuz [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Deptuch, Grzegorz [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Deveaux, Michael [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); GSI, Planckstrasse 1, Darmstadt 64291 (Germany); Dorokhov, Andrei [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Dulinski, Wojciech [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Fourches, Nicolas [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Goffe, Mathieu [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Grandjean, Damien; Guilloux, Fabrice [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Heini, Sebastien [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]|[GSI, Planckstrasse 1, Darmstadt 64291 (Germany); Himmi, Abdelkader [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Hu, Christine [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Jaaskelainen, Kimmo; Li, Yan; Lutz, Pierre; Orsini, Fabienne [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Pellicioli, Michel; Shabetai, Alexandre; Valin, Isabelle; Winter, Marc [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)

2006-11-30

Several development directions intended to adapt and optimize monolithic active pixel sensors for specific applications are presented in this work. The first example, compatible with the STAR microvertex upgrade, is based on a simple two-transistor pixel circuitry. It is suited for a long integration time, room-temperature operation and minimum power dissipation. In another approach for this application, a specific readout method is proposed, allowing optimization of the integration time independently of the full frame-readout time. The circuit consists of an in-pixel front-end voltage amplifier, with a gain on the order of five, followed by two analog memory cells. The extended version of this scheme, based on the implementation of more memory cells per pixel, is the solution considered for the outer layers of a microvertex detector at the international linear collider. For the two innermost layers, a circuit allowing fast frame scans together with on-line, on-chip data sparsification is proposed. The first results of this prototype demonstrate that the fixed pattern dispersion is reduced below a noise level of 15 e{sup -}, allowing the use of a single comparator or a low-resolution ADC per pixel column. A common element for most of the mentioned readout schemes is a low-noise, low power consumption, layout efficient in-pixel amplifier. A review of possible solutions for this element together with some experimental results is presented.

SLID-ICV Vertical Integration Technology for the ATLAS Pixel Upgrades

CERN Document Server

INSPIRE-00219560; Moser, H.G.; Nisius, R.; Richter, R.H.; Weigell, P.

We present the results of the characterization of pixel modules composed of 75 μm thick n-in-p sensors and ATLAS FE-I3 chips, interconnected with the SLID (Solid Liquid Inter-Diffusion) technology. This technique, developed at Fraunhofer-EMFT, is explored as an alternative to the bump-bonding process. These modules have been designed to demonstrate the feasibility of a very compact detector to be employed in the future ATLAS pixel upgrades, making use of vertical integration technologies. This module concept also envisages Inter-Chip-Vias (ICV) to extract the signals from the backside of the chips, thereby achieving a higher fraction of active area with respect to the present pixel module design. In the case of the demonstrator module, ICVs are etched over the original wire bonding pads of the FE-I3 chip. In the modules with ICVs the FE-I3 chips will be thinned down to 50 um. The status of the ICV preparation is presented.

A 128 x 128 CMOS Active Pixel Image Sensor for Highly Integrated Imaging Systems

Science.gov (United States)

Mendis, Sunetra K.; Kemeny, Sabrina E.; Fossum, Eric R.

1993-01-01

A new CMOS-based image sensor that is intrinsically compatible with on-chip CMOS circuitry is reported. The new CMOS active pixel image sensor achieves low noise, high sensitivity, X-Y addressability, and has simple timing requirements. The image sensor was fabricated using a 2 micrometer p-well CMOS process, and consists of a 128 x 128 array of 40 micrometer x 40 micrometer pixels. The CMOS image sensor technology enables highly integrated smart image sensors, and makes the design, incorporation and fabrication of such sensors widely accessible to the integrated circuit community.

Conceptual design of 3D integrated pixel sensors for the innermost layer of the ILC vertex detector

International Nuclear Information System (INIS)

Fu, Y; Hu-Guo, C; Dorokhov, A; Zhao, W; Hu, Y; Torheim, O

2011-01-01

The paper presents a design of CMOS Pixel Sensor (CPS) using the vertical integration technology (3DIT), expected to alleviate the most essential limitations of 2D-CPS. Our objective is to develop an intelligent architecture in order to meet the requirements of the innermost layer of the International Linear Collider (ILC) vertex detectors, which are particularly demanding in spatial resolution of less than 3 μm and associated frame readout time of 10 μs. The sensor, with a pixel pitch of 23 μm, will be composed of 3-tiers Integrated Circuits (IC) with different functionalities: detection with in pixel analogue processing, pixel-level 3-bit Analogue to Digital Conversion (ADC) and fast parallel sparse readout.

High-speed imaging at high x-ray energy: CdTe sensors coupled to charge-integrating pixel array detectors

Energy Technology Data Exchange (ETDEWEB)

Becker, Julian; Tate, Mark W.; Shanks, Katherine S.; Philipp, Hugh T.; Weiss, Joel T.; Purohit, Prafull [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853 (United States); Chamberlain, Darol [Cornell High Energy Synchrotron Source (CHESS), 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

Pixel Array Detectors (PADs) consist of an x-ray sensor layer bonded pixel-by-pixel to an underlying readout chip. This approach allows both the sensor and the custom pixel electronics to be tailored independently to best match the x-ray imaging requirements. Here we describe the hybridization of CdTe sensors to two different charge-integrating readout chips, the Keck PAD and the Mixed-Mode PAD (MM-PAD), both developed previously in our laboratory. The charge-integrating architecture of each of these PADs extends the instantaneous counting rate by many orders of magnitude beyond that obtainable with photon counting architectures. The Keck PAD chip consists of rapid, 8-frame, in-pixel storage elements with framing periods <150 ns. The second detector, the MM-PAD, has an extended dynamic range by utilizing an in-pixel overflow counter coupled with charge removal circuitry activated at each overflow. This allows the recording of signals from the single-photon level to tens of millions of x-rays/pixel/frame while framing at 1 kHz. Both detector chips consist of a 128×128 pixel array with (150 µm){sup 2} pixels.

A new method to improve multiplication factor in micro-pixel avalanche photodiodes with high pixel density

Energy Technology Data Exchange (ETDEWEB)

Sadygov, Z. [National Nuclear Research Center, Baku (Azerbaijan); Joint Institute for Nuclear Research, Dubna (Russian Federation); Ahmadov, F. [National Nuclear Research Center, Baku (Azerbaijan); Khorev, S. [Zecotek Photonics Inc., Vancouver (Canada); Sadigov, A., E-mail: saazik@yandex.ru [National Nuclear Research Center, Baku (Azerbaijan); Suleymanov, S. [National Nuclear Research Center, Baku (Azerbaijan); Madatov, R.; Mehdiyeva, R. [Institute of Radiation Problems, Baku (Azerbaijan); Zerrouk, F. [Zecotek Photonics Inc., Vancouver (Canada)

2016-07-11

Presented is a new model describing development of the avalanche process in time, taking into account the dynamics of electric field within the depleted region of the diode and the effect of parasitic capacitance shunting individual quenching micro-resistors on device parameters. Simulations show that the effective capacitance of a single pixel, which defines the multiplication factor, is the sum of the pixel capacitance and a parasitic capacitance shunting its quenching micro-resistor. Conclusions obtained as a result of modeling open possibilities of improving the pixel gain in micropixel avalanche photodiodes with high pixel density (or low pixel capacitance).

A 2D 4×4 Channel Readout ASIC for Pixelated CdTe Detectors for Medical Imaging Applications.

Science.gov (United States)

Macias-Montero, Jose-Gabriel; Sarraj, Maher; Chmeissani, Mokhtar; Martínez, Ricardo; Puigdengoles, Carles

2015-10-01

We present a 16-channel readout integrated circuit (ROIC) with nanosecond-resolution time to digital converter (TDC) for pixelated Cadmium Telluride (CdTe) gamma-ray detectors. The 4 × 4 pixel array ROIC is the proof of concept of the 10 × 10 pixel array readout ASIC for positron-emission tomography (PET) scanner, positron-emission mammography (PEM) scanner, and Compton gamma camera. The electronics of each individual pixel integrates an analog front-end with switchable gain, an analog to digital converter (ADC), configuration registers, and a 4-state digital controller. For every detected photon, the pixel electronics provides the energy deposited in the detector with 10-bit resolution, and a fast trigger signal for time stamp. The ASIC contains the 16-pixel matrix electronics, a digital controller, five global voltage references, a TDC, a temperature sensor, and a band-gap based current reference. The ASIC has been fabricated with TSMC 0.25 μ m mixed-signal CMOS technology and occupies an area of 5.3 mm × 6.8 mm. The TDC shows a resolution of 95.5 ps, a precision of 600 ps at full width half maximum (FWHM), and a power consumption of 130 μ W. In acquisition mode, the total power consumption of every pixel is 200 μ W. An equivalent noise charge (ENC) of 160 e - RMS at maximum gain and negative polarity conditions has been measured at room temperature.

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.

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.

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.

PIXEL 2010 - A Resume

International Nuclear Information System (INIS)

Wermes, N.

2011-01-01

The Pixel 2010 conference focused on semiconductor pixel detectors for particle tracking/vertexing as well as for imaging, in particular for synchrotron light sources and XFELs. The big LHC hybrid pixel detectors have impressively started showing their capabilities. X-ray imaging detectors, also using the hybrid pixel technology, have greatly advanced the experimental possibilities for diffraction experiments. Monolithic or semi-monolithic devices like CMOS active pixels and DEPFET pixels have now reached a state such that complete vertex detectors for RHIC and superKEKB are being built with these technologies. Finally, new advances towards fully monolithic active pixel detectors, featuring full CMOS electronics merged with efficient signal charge collection, exploiting standard CMOS technologies, SOI and/or 3D integration, show the path for the future. This resume attempts to extract the main statements of the results and developments presented at this conference.

Testing multistage gain and offset trimming in a single photon counting IC with a charge sharing elimination algorithm

International Nuclear Information System (INIS)

Krzyżanowska, A.; Gryboś, P.; Szczygieł, R.; Maj, P.

2015-01-01

Designing a hybrid pixel detector readout electronics operating in a single photon counting mode is a very challenging process, where many main parameters are optimized in parallel (e.g. gain, noise, and threshold dispersion). Additional requirements for a smaller pixel size with extended functionality push designers to use new deep sub-micron technologies. Minimizing the channel size is possible, however, with a decreased pixel size, the charge sharing effect becomes a more important issue. To overcome this problem, we designed an integrated circuit prototype produced in CMOS 40 nm technology, which has an extended functionality of a single pixel. A C8P1 algorithm for the charge sharing effect compensation was implemented. In the algorithm's first stage the charge is rebuilt in a signal rebuilt hub fed by the CSA (charge sensitive amplifier) outputs from four neighbouring pixels. Then, the pixel with the biggest amount of charge is chosen, after a comparison with all the adjacent ones. In order to process the data in such a complicated way, a certain architecture of a single channel was proposed, which allows for: ⋅ processing the signal with the possibility of total charge reconstruction (by connecting with the adjacent pixels), ⋅ a comparison of certain pixel amplitude to its 8 neighbours, ⋅ the extended testability of each block inside the channel to measure CSA gain dispersion, shaper gain dispersion, threshold dispersion (including the simultaneous generation of different pulse amplitudes from different pixels), ⋅ trimming all the necessary blocks for proper operation. We present a solution for multistage gain and offset trimming implemented in the IC prototype. It allows for minimization of the total charge extraction errors, minimization of threshold dispersion in the pixel matrix and minimization of errors of comparison of certain pixel pulse amplitudes with all its neighbours. The detailed architecture of a single channel is presented

3D integration technology for hybrid pixel detectors designed for particle physics and imaging experiments

International Nuclear Information System (INIS)

Henry, D.; Berthelot, A.; Cuchet, R.; Chantre, C.; Campbell, M.; Tick, T.

2012-01-01

Hybrid pixel detectors are now widely used in particle physics experiments and are becoming established 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. 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 advantages of 3D Integration come from reduced inter chip dead area even on large surfaces and from improved detector construction yield resulting from the use of single chip 4-side buttable tiles. For many years, numerous R and centres and companies have put a lot of effort into developing 3D integration technologies and today, some mature technologies are ready for prototyping and production. The core technology of the 3D integration is the TSV (Through Silicon Via) and for many years, LETI has developed those technologies for various types of applications. In this paper we present how one of the TSV approaches developed by LETI, called TSV last, has been applied to a readout wafer containing readout chips intended for a hybrid pixel detector assembly. In the first part of this paper, the 3D design adapted to the read-out chip will be described. Then the complete process flow will be explained and, finally, the test strategy adopted and

Characterization of Pixel Sensors

CERN Document Server

Oliveira, Felipe Ferraz

2017-01-01

It was commissioned at CERN ATLAS pixel group a fluorescence setup for characterization of pixel sensors. The idea is to measure the energies of different targets to calibrate your sensor. It was measured four matrices (80, 95, 98 and 106) of the Investigator1 sensor with different deep PW using copper, iron and titanium as target materials. The matrix 80 has a higher gain (0.065 ± 0.002) and matrix 106 has a better energy resolution (0.05 ± 0.04). The noise of the setup is around 3.6 mV .

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)

First operation of a hybrid photon detector prototype with electrostatic cross-focussing and integrated silicon pixel readout

International Nuclear Information System (INIS)

Alemi, M.; Campbell, M.; Gys, T.; Mikulec, B.; Piedigrossi, D.; Puertolas, D.; Rosso, E.; Schomaker, R.; Snoeys, W.; Wyllie, K.

2000-01-01

We report on the first operation of a hybrid photon detector prototype with integrated silicon pixel readout for the ring imaging Cherenkov detectors of the LHCb experiment. The photon detector is based on a cross-focussed image intensifier tube geometry where the image is de-magnified by a factor of 4. The anode consists of a silicon pixel array, bump-bonded to a binary readout chip with matching pixel electronics. The prototype has been characterized using a low-intensity light-emitting diode operated in pulsed mode. Its performance in terms of single-photoelectron detection efficiency and imaging properties is presented. A model of photoelectron detection is proposed, and is shown to be in good agreement with the experimental data. It includes an estimate of the charge signal generated in the silicon detector, and the combined effects of the comparator threshold spread of the pixel readout chip, charge sharing at the pixel boundaries and back-scattering of the photoelectrons at the silicon detector surface

First operation of a hybrid photon detector prototype with electrostatic cross-focussing and integrated silicon pixel readout

Energy Technology Data Exchange (ETDEWEB)

Alemi, M.; Campbell, M.; Gys, T. E-mail: thierry.gys@cern.ch; Mikulec, B.; Piedigrossi, D.; Puertolas, D.; Rosso, E.; Schomaker, R.; Snoeys, W.; Wyllie, K

2000-07-11

We report on the first operation of a hybrid photon detector prototype with integrated silicon pixel readout for the ring imaging Cherenkov detectors of the LHCb experiment. The photon detector is based on a cross-focussed image intensifier tube geometry where the image is de-magnified by a factor of 4. The anode consists of a silicon pixel array, bump-bonded to a binary readout chip with matching pixel electronics. The prototype has been characterized using a low-intensity light-emitting diode operated in pulsed mode. Its performance in terms of single-photoelectron detection efficiency and imaging properties is presented. A model of photoelectron detection is proposed, and is shown to be in good agreement with the experimental data. It includes an estimate of the charge signal generated in the silicon detector, and the combined effects of the comparator threshold spread of the pixel readout chip, charge sharing at the pixel boundaries and back-scattering of the photoelectrons at the silicon detector surface.

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.

Qualification Procedures of the CMS Pixel Barrel Modules

CERN Document Server

Starodumov, A; Horisberger, R.; Kastli, H.Chr.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Trueb, P.

2006-01-01

The CMS pixel barrel system will consist of three layers built of about 800 modules. One module contains 66560 readout channels and the full pixel barrel system about 48 million channels. It is mandatory to test each channel for functionality, noise level, trimming mechanism, and bump bonding quality. Different methods to determine the bump bonding yield with electrical measurements have been developed. Measurements of several operational parameters are also included in the qualification procedure. Among them are pixel noise, gains and pedestals. Test and qualification procedures of the pixel barrel modules are described and some results are presented.

The electro-mechanical integration of the NA62 GigaTracker time tagging pixel detector

CERN Document Server

Morel, M; Aglieri Rinella, G; Carassiti, V; Ceccucci, A; Daguin, J; Fiorini, M; Jarron, P; Kaplon, J; Mapelli, A; Marchetto, F; Noy, M; Nuessle, G; Perktold, L; Petagna, P; Riedler, P

2010-01-01

The NA62 GigaTracker is a low mass time tagging hybrid pixel detector operating in a beam with a particle rate of 750 MHz. It consists of three stations with a sensor size of 60 × 27mm2 containing 18000 pixels, each 300 × 300μm2. The active area is connected to a matrix of 2 × 5 pixel ASICs, which time tag the arrival of the particles with a binning of 100 ps. The detector operates in vacuum at -20 to 0°C and the material budget per station must be below 0.5% X0. Due to the high radiation environment of 2 × 1014 1 MeV neutron equivalent cm−2/yr−1 it is planned to exchange the detector modules regularly. The low material budget, cooling requirements and the request for easy module access has driven the electro-mechanical integration of the GigaTracker, which is presented in this paper

A 20 Mfps high frame-depth CMOS burst-mode imager with low power in-pixel NMOS-only passive amplifier

Science.gov (United States)

Wu, L.; San Segundo Bello, D.; Coppejans, P.; Craninckx, J.; Wambacq, P.; Borremans, J.

2017-02-01

This paper presents a 20 Mfps 32 × 84 pixels CMOS burst-mode imager featuring high frame depth with a passive in-pixel amplifier. Compared to the CCD alternatives, CMOS burst-mode imagers are attractive for their low power consumption and integration of circuitry such as ADCs. Due to storage capacitor size and its noise limitations, CMOS burst-mode imagers usually suffer from a lower frame depth than CCD implementations. In order to capture fast transitions over a longer time span, an in-pixel CDS technique has been adopted to reduce the required memory cells for each frame by half. Moreover, integrated with in-pixel CDS, an in-pixel NMOS-only passive amplifier alleviates the kTC noise requirements of the memory bank allowing the usage of smaller capacitors. Specifically, a dense 108-cell MOS memory bank (10fF/cell) has been implemented inside a 30μm pitch pixel, with an area of 25 × 30μm2 occupied by the memory bank. There is an improvement of about 4x in terms of frame depth per pixel area by applying in-pixel CDS and amplification. With the amplifier's gain of 3.3, an FD input-referred RMS noise of 1mV is achieved at 20 Mfps operation. While the amplification is done without burning DC current, including the pixel source follower biasing, the full pixel consumes 10μA at 3.3V supply voltage at full speed. The chip has been fabricated in imec's 130nm CMOS CIS technology.

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

Characterization of the column-based priority logic readout of Topmetal-II− CMOS pixel direct charge sensor

International Nuclear Information System (INIS)

An, M.; Zhang, W.; Xiao, L.; Gao, C.; Chen, C.; Huang, G.; Ji, R.; Liu, J.; Pei, H.; Sun, X.; Wang, K.; Yang, P.; Zhou, W.; Han, M.; Mei, Y.; Li, X.; Sun, Q.

2017-01-01

We present the detailed study of the digital readout of Topmetal-II - CMOS pixel direct charge sensor. Topmetal-II - is an integrated sensor with an array of 72×72 pixels each capable of directly collecting external charge through exposed metal electrodes in the topmost metal layer. In addition to the time-shared multiplexing readout of the analog output from Charge Sensitive Amplifiers in each pixel, hits are also generated through comparators in each pixel with individually adjustable thresholds. The hits are read out via a column-based priority logic structure, retaining both hit location and time information. The in-array column-based priority logic features with a full clock-less circuitry hence there is no continuously running clock distributed in the pixel and matrix logic. These characteristics enable its use as the charge readout device in future Time Projection Chambers without gaseous gain mechanism, which has unique advantages in low background and low rate-density experiments. We studied the detailed working behavior and performance of this readout, and demonstrated its functional validity and potential in imaging applications.

Transition-edge sensor pixel parameter design of the microcalorimeter array for the x-ray integral field unit on Athena

Science.gov (United States)

Smith, S. J.; Adams, J. S.; Bandler, S. R.; Betancourt-Martinez, G. L.; Chervenak, J. A.; Chiao, M. P.; Eckart, M. E.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Miniussi, A. R.; Porter, F. S.; Sadleir, J. E.; Sakai, K.; Wakeham, N. A.; Wassell, E. J.; Yoon, W.; Bennett, D. A.; Doriese, W. B.; Fowler, J. W.; Hilton, G. C.; Morgan, K. M.; Pappas, C. G.; Reintsema, C. N.; Swetz, D. S.; Ullom, J. N.; Irwin, K. D.; Akamatsu, H.; Gottardi, L.; den Hartog, R.; Jackson, B. D.; van der Kuur, J.; Barret, D.; Peille, P.

2016-07-01

The focal plane of the X-ray integral field unit (X-IFU) for ESA's Athena X-ray observatory will consist of 4000 transition edge sensor (TES) x-ray microcalorimeters optimized for the energy range of 0.2 to 12 keV. The instrument will provide unprecedented spectral resolution of 2.5 eV at energies of up to 7 keV and will accommodate photon fluxes of 1 mCrab (90 cps) for point source observations. The baseline configuration is a uniform large pixel array (LPA) of 4.28" pixels that is read out using frequency domain multiplexing (FDM). However, an alternative configuration under study incorporates an 18 × 18 small pixel array (SPA) of 2" pixels in the central 36" region. This hybrid array configuration could be designed to accommodate higher fluxes of up to 10 mCrab (900 cps) or alternately for improved spectral performance (< 1.5 eV) at low count-rates. In this paper we report on the TES pixel designs that are being optimized to meet these proposed LPA and SPA configurations. In particular we describe details of how important TES parameters are chosen to meet the specific mission criteria such as energy resolution, count-rate and quantum efficiency, and highlight performance trade-offs between designs. The basis of the pixel parameter selection is discussed in the context of existing TES arrays that are being developed for solar and x-ray astronomy applications. We describe the latest results on DC biased diagnostic arrays as well as large format kilo-pixel arrays and discuss the technical challenges associated with integrating different array types on to a single detector die.

Transition-Edge Sensor Pixel Parameter Design of the Microcalorimeter Array for the X-Ray Integral Field Unit on Athena

Science.gov (United States)

Smith, S. J.; Adams, J. S.; Bandler, S. R.; Betancourt-Martinez, G. L.; Chervenak, J. A.; Chiao, M. P.; Eckart, M. E.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.;

Integrated X-ray and charged particle active pixel CMOS sensor arrays using an epitaxial silicon sensitive region

International Nuclear Information System (INIS)

Kleinfelder, Stuart; Bichsel, Hans; Bieser, Fred; Matis, Howard S.; Rai, Gulshan; Retiere, Fabrice; Weiman, Howard; Yamamoto, Eugene

2002-01-01

Integrated CMOS Active Pixel Sensor (APS) arrays have been fabricated and tested using X-ray and electron sources. The 128 by 128 pixel arrays, designed in a standard 0.25 micron process, use a ∼10 micron epitaxial silicon layer as a deep detection region. The epitaxial layer has a much greater thickness than the surface features used by standard CMOS APS, leading to stronger signals and potentially better signal-to-noise ratio (SNR). On the other hand, minority carriers confined within the epitaxial region may diffuse to neighboring pixels, blur images and reduce peak signal intensity. But for low-rate, sparse-event images, centroid analysis of this diffusion may be used to increase position resolution. Careful trade-offs involving pixel size and sense-node area verses capacitance must be made to optimize overall performance. The prototype sensor arrays, therefore, include a range of different pixel designs, including different APS circuits and a range of different epitaxial layer contact structures. The fabricated arrays were tested with 1.5 GeV electrons and Fe-55 X-ray sources, yielding a measured noise of 13 electrons RMS and an SNR for single Fe-55 X-rays of greater than 38

Low noise signal-to-noise ratio enhancing readout circuit for current-mediated active pixel sensors

International Nuclear Information System (INIS)

Ottaviani, Tony; Karim, Karim S.; Nathan, Arokia; Rowlands, John A.

2006-01-01

Diagnostic digital fluoroscopic applications continuously expose patients to low doses of x-ray radiation, posing a challenge to both the digital imaging pixel and readout electronics when amplifying small signal x-ray inputs. Traditional switch-based amorphous silicon imaging solutions, for instance, have produced poor signal-to-noise ratios (SNRs) at low exposure levels owing to noise sources from the pixel readout circuitry. Current-mediated amorphous silicon pixels are an improvement over conventional pixel amplifiers with an enhanced SNR across the same low-exposure range, but whose output also becomes nonlinear with increasing dosage. A low-noise SNR enhancing readout circuit has been developed that enhances the charge gain of the current-mediated active pixel sensor (C-APS). The solution takes advantage of the current-mediated approach, primarily integrating the signal input at the desired frequency necessary for large-area imaging, while adding minimal noise to the signal readout. Experimental data indicates that the readout circuit can detect pixel outputs over a large bandwidth suitable for real-time digital diagnostic x-ray fluoroscopy. Results from hardware testing indicate that the minimum achievable C-APS output current that can be discerned at the digital fluoroscopic output from the enhanced SNR readout circuit is 0.341 nA. The results serve to highlight the applicability of amorphous silicon current-mediated pixel amplifiers for large-area flat panel x-ray imagers

Dead pixel replacement in LWIR microgrid polarimeters.

Science.gov (United States)

Ratliff, Bradley M; Tyo, J Scott; Boger, James K; Black, Wiley T; Bowers, David L; Fetrow, Matthew P

2007-06-11

LWIR imaging arrays are often affected by nonresponsive pixels, or "dead pixels." These dead pixels can severely degrade the quality of imagery and often have to be replaced before subsequent image processing and display of the imagery data. For LWIR arrays that are integrated with arrays of micropolarizers, the problem of dead pixels is amplified. Conventional dead pixel replacement (DPR) strategies cannot be employed since neighboring pixels are of different polarizations. In this paper we present two DPR schemes. The first is a modified nearest-neighbor replacement method. The second is a method based on redundancy in the polarization measurements.We find that the redundancy-based DPR scheme provides an order-of-magnitude better performance for typical LWIR polarimetric data.

Evaluation of a single-pixel one-transistor active pixel sensor for fingerprint imaging

Science.gov (United States)

Xu, Man; Ou, Hai; Chen, Jun; Wang, Kai

2015-08-01

Since it first appeared in iPhone 5S in 2013, fingerprint identification (ID) has rapidly gained popularity among consumers. Current fingerprint-enabled smartphones unanimously consists of a discrete sensor to perform fingerprint ID. This architecture not only incurs higher material and manufacturing cost, but also provides only static identification and limited authentication. Hence as the demand for a thinner, lighter, and more secure handset grows, we propose a novel pixel architecture that is a photosensitive device embedded in a display pixel and detects the reflected light from the finger touch for high resolution, high fidelity and dynamic biometrics. To this purpose, an amorphous silicon (a-Si:H) dual-gate photo TFT working in both fingerprint-imaging mode and display-driving mode will be developed.

Pixel-by-pixel mean transit time without deconvolution.

Science.gov (United States)

Dobbeleir, Andre A; Piepsz, Amy; Ham, Hamphrey R

2008-04-01

Mean transit time (MTT) within a kidney is given by the integral of the renal activity on a well-corrected renogram between time zero and time t divided by the integral of the plasma activity between zero and t, providing that t is close to infinity. However, as the data acquisition of a renogram is finite, the MTT calculated using this approach might result in the underestimation of the true MTT. To evaluate the degree of this underestimation we conducted a simulation study. One thousand renograms were created by convoluting various plasma curves obtained from patients with different renal clearance levels with simulated retentions curves having different shapes and mean transit times. For a 20 min renogram, the calculated MTT started to underestimate the MTT when the MTT was higher than 6 min. The longer the MTT, the greater was the underestimation. Up to a MTT value of 6 min, the error on the MTT estimation is negligible. As normal cortical transit is less than 2 min, this approach is used for patients to calculate pixel-to-pixel cortical mean transit time and to create a MTT parametric image without deconvolution.

THE KEPLER PIXEL RESPONSE FUNCTION

International Nuclear Information System (INIS)

Bryson, Stephen T.; Haas, Michael R.; Dotson, Jessie L.; Koch, David G.; Borucki, William J.; Tenenbaum, Peter; Jenkins, Jon M.; Chandrasekaran, Hema; Caldwell, Douglas A.; Klaus, Todd; Gilliland, Ronald L.

2010-01-01

Kepler seeks to detect sequences of transits of Earth-size exoplanets orbiting solar-like stars. Such transit signals are on the order of 100 ppm. The high photometric precision demanded by Kepler requires detailed knowledge of how the Kepler pixels respond to starlight during a nominal observation. This information is provided by the Kepler pixel response function (PRF), defined as the composite of Kepler's optical point-spread function, integrated spacecraft pointing jitter during a nominal cadence and other systematic effects. To provide sub-pixel resolution, the PRF is represented as a piecewise-continuous polynomial on a sub-pixel mesh. This continuous representation allows the prediction of a star's flux value on any pixel given the star's pixel position. The advantages and difficulties of this polynomial representation are discussed, including characterization of spatial variation in the PRF and the smoothing of discontinuities between sub-pixel polynomial patches. On-orbit super-resolution measurements of the PRF across the Kepler field of view are described. Two uses of the PRF are presented: the selection of pixels for each star that maximizes the photometric signal-to-noise ratio for that star, and PRF-fitted centroids which provide robust and accurate stellar positions on the CCD, primarily used for attitude and plate scale tracking. Good knowledge of the PRF has been a critical component for the successful collection of high-precision photometry by Kepler.

Active pixel sensor pixel having a photodetector whose output is coupled to an output transistor gate

Science.gov (United States)

Fossum, Eric R. (Inventor); Nakamura, Junichi (Inventor); Kemeny, Sabrina E. (Inventor)

2005-01-01

An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node. There is also a readout circuit, part of which can be disposed at the bottom of each column of cells and be common to all the cells in the column. A Simple Floating Gate (SFG) pixel structure could also be employed in the imager to provide a non-destructive readout and smaller pixel sizes.

The DELPHI pixels

International Nuclear Information System (INIS)

Becks, K.H.; Brunet, J.M.

1997-01-01

To improve tracking in the very forward direction for running at LEP200, the angular acceptance of the DELPHI Vertex detector has been extended from 45 to 11 with respect to the beam axis. Pixel detector crowns cover the region between 25 and 13 . Due to very tight space and material thickness constraints it was necessary to develop new techniques (integrated busses in the detector substrate, high density layout on Kapton, etc.). About 1000 cm 2 of pixels are already installed and working in DELPHI. Techniques, tests and production of these detectors will be described, as well as the main problems encountered during this work. (orig.)

Pixel 2010: A résumé

CERN Document Server

Wermes, Norbert

2011-01-01

The Pixel 2010 conference focused on semiconductor pixel detectors for particle tracking/vertexing as well as for imaging, in particular for synchrotron light sources and XFELs. The big LHC hybrid pixel detectors have impressively started showing their capabilities. X-ray imaging detectors, also using the hybrid pixel technology, have greatly advanced the experimental possibilities for diffraction experiments. Monolithic or semi-monolithic devices like CMOS active pixels and DEPFET pixels have now reached a state such that complete vertex detectors for RHIC and superKEKB are being built with these technologies. Finally, new advances towards fully monolithic active pixel detectors, featuring full CMOS electronics merged with efficient signal charge collection, exploiting standard CMOS technologies, SOI and/or 3D integration, show the path for the future. This résumé attempts to extract the main statements of the results and developments presented at this conference.

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.

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

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

Focal plane array with modular pixel array components for scalability

Science.gov (United States)

Kay, Randolph R; Campbell, David V; Shinde, Subhash L; Rienstra, Jeffrey L; Serkland, Darwin K; Holmes, Michael L

2014-12-09

A modular, scalable focal plane array is provided as an array of integrated circuit dice, wherein each die includes a given amount of modular pixel array circuitry. The array of dice effectively multiplies the amount of modular pixel array circuitry to produce a larger pixel array without increasing die size. Desired pixel pitch across the enlarged pixel array is preserved by forming die stacks with each pixel array circuitry die stacked on a separate die that contains the corresponding signal processing circuitry. Techniques for die stack interconnections and die stack placement are implemented to ensure that the desired pixel pitch is preserved across the enlarged pixel array.

32 x 16 CMOS smart pixel array for optical interconnects

Science.gov (United States)

Kim, Jongwoo; Guilfoyle, Peter S.; Stone, Richard V.; Hessenbruch, John M.; Choquette, Kent D.; Kiamilev, Fouad E.

2000-05-01

Free space optical interconnects can increase throughput capacities and eliminate much of the energy consumption required for `all electronic' systems. High speed optical interconnects can be achieved by integrating optoelectronic devices with conventional electronics. Smart pixel arrays have been developed which use optical interconnects. An individual smart pixel cell is composed of a vertical cavity surface emitting laser (VCSEL), a photodetector, an optical receiver, a laser driver, and digital logic circuitry. Oxide-confined VCSELs are being developed to operate at 850 nm with a threshold current of approximately 1 mA. Multiple quantum well photodetectors are being fabricated from AlGaAs for use with the 850 nm VCSELs. The VCSELs and photodetectors are being integrated with complementary metal oxide semiconductor (CMOS) circuitry using flip-chip bonding. CMOS circuitry is being integrated with a 32 X 16 smart pixel array. The 512 smart pixels are serially linked. Thus, an entire data stream may be clocked through the chip and output electrically by the last pixel. Electrical testing is being performed on the CMOS smart pixel array. Using an on-chip pseudo random number generator, a digital data sequence was cycled through the chip verifying operation of the digital circuitry. Although, the prototype chip was fabricated in 1.2 micrometers technology, simulations have demonstrated that the array can operate at 1 Gb/s per pixel using 0.5 micrometers technology.

New generation of monolithic active pixel sensors for charged particle detection

International Nuclear Information System (INIS)

Deptuch, G.

2002-09-01

Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a 55 Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 μm and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 10 12 n/cm 2 and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

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.

1T Pixel Using Floating-Body MOSFET for CMOS Image Sensors

Directory of Open Access Journals (Sweden)

Guo-Neng Lu

2009-01-01

Full Text Available We present a single-transistor pixel for CMOS image sensors (CIS. It is a floating-body MOSFET structure, which is used as photo-sensing device and source-follower transistor, and can be controlled to store and evacuate charges. Our investigation into this 1T pixel structure includes modeling to obtain analytical description of conversion gain. Model validation has been done by comparing theoretical predictions and experimental results. On the other hand, the 1T pixel structure has been implemented in different configurations, including rectangular-gate and ring-gate designs, and variations of oxidation parameters for the fabrication process. The pixel characteristics are presented and discussed.

1T Pixel Using Floating-Body MOSFET for CMOS Image Sensors.

Science.gov (United States)

Lu, Guo-Neng; Tournier, Arnaud; Roy, François; Deschamps, Benoît

2009-01-01

We present a single-transistor pixel for CMOS image sensors (CIS). It is a floating-body MOSFET structure, which is used as photo-sensing device and source-follower transistor, and can be controlled to store and evacuate charges. Our investigation into this 1T pixel structure includes modeling to obtain analytical description of conversion gain. Model validation has been done by comparing theoretical predictions and experimental results. On the other hand, the 1T pixel structure has been implemented in different configurations, including rectangular-gate and ring-gate designs, and variations of oxidation parameters for the fabrication process. The pixel characteristics are presented and discussed.

A novel source–drain follower for monolithic active pixel sensors

Energy Technology Data Exchange (ETDEWEB)

Gao, C., E-mail: chaosong.gao@mails.ccnu.edu.cn [Central China Normal University, Wuhan (China); Aglieri, G.; Hillemanns, H. [CERN, Geneva (Switzerland); Huang, G., E-mail: gmhuang@phy.ccnu.edu.cn [Central China Normal University, Wuhan (China); Junique, A.; Keil, M. [CERN, Geneva (Switzerland); Kim, D. [Dongguk University, Seoul (Korea, Republic of); Yonsei University, Seoul (Korea, Republic of); Kofarago, M.; Kugathasan, T.; Mager, M.; Marin Tobon, C.A.; Martinengo, P. [CERN, Geneva (Switzerland); Mugnier, H. [Mind, Archamps (France); Musa, L. [CERN, Geneva (Switzerland); Lee, S. [Dongguk University, Seoul (Korea, Republic of); Yonsei University, Seoul (Korea, Republic of); Reidt, F. [CERN, Geneva (Switzerland); Ruprecht-Karls-Universitat Heidelberg, Heidelberg (Germany); Riedler, P. [CERN, Geneva (Switzerland); Rousset, J. [Mind, Archamps (France); Sielewicz, K.M. [CERN, Geneva (Switzerland); Warsaw University of Technology, Warsaw (Poland); Snoeys, W. [CERN, Geneva (Switzerland); and others

2016-09-21

Monolithic active pixel sensors (MAPS) receive interest in tracking applications in high energy physics as they integrate sensor and readout electronics in one silicon die with potential for lower material budget and cost, and better performance. Source followers (SFs) are widely used for MAPS readout: they increase charge conversion gain 1/C{sub eff} or decrease the effective sensing node capacitance C{sub eff} because the follower action compensates part of the input capacitance. Charge conversion gain is critical for analog power consumption and therefore for material budget in tracking applications, and also has direct system impact. This paper presents a novel source–drain follower (SDF), where both source and drain follow the gate potential improving charge conversion gain. For the inner tracking system (ITS) upgrade of the ALICE experiment at CERN, low material budget is a primary requirement. The SDF circuit was studied as part of the effort to optimize the effective capacitance of the sensing node. The collection electrode, input transistor and routing metal all contribute to C{sub eff}. Reverse sensor bias reduces the collection electrode capacitance. The novel SDF circuit eliminates the contribution of the input transistor to C{sub eff}, reduces the routing contribution if additional shielding is introduced, provides a way to estimate the capacitance of the sensor itself, and has a voltage gain closer to unity than the standard SF. The SDF circuit has a somewhat larger area with a somewhat smaller bandwidth, but this is acceptable in most cases. A test chip, manufactured in a 180 nm CMOS image sensor process, implements small prototype pixel matrices in different flavors to compare the standard SF to the novel SF and to the novel SF with additional shielding. The effective sensing node capacitance was measured using a {sup 55}Fe source. Increasing reverse substrate bias from −1 V to −6 V reduces C{sub eff} by 38% and the equivalent noise charge

A novel source–drain follower for monolithic active pixel sensors

International Nuclear Information System (INIS)

Gao, C.; Aglieri, G.; Hillemanns, H.; Huang, G.; Junique, A.; Keil, M.; Kim, D.; Kofarago, M.; Kugathasan, T.; Mager, M.; Marin Tobon, C.A.; Martinengo, P.; Mugnier, H.; Musa, L.; Lee, S.; Reidt, F.; Riedler, P.; Rousset, J.; Sielewicz, K.M.; Snoeys, W.

2016-01-01

Monolithic active pixel sensors (MAPS) receive interest in tracking applications in high energy physics as they integrate sensor and readout electronics in one silicon die with potential for lower material budget and cost, and better performance. Source followers (SFs) are widely used for MAPS readout: they increase charge conversion gain 1/C_e_f_f or decrease the effective sensing node capacitance C_e_f_f because the follower action compensates part of the input capacitance. Charge conversion gain is critical for analog power consumption and therefore for material budget in tracking applications, and also has direct system impact. This paper presents a novel source–drain follower (SDF), where both source and drain follow the gate potential improving charge conversion gain. For the inner tracking system (ITS) upgrade of the ALICE experiment at CERN, low material budget is a primary requirement. The SDF circuit was studied as part of the effort to optimize the effective capacitance of the sensing node. The collection electrode, input transistor and routing metal all contribute to C_e_f_f. Reverse sensor bias reduces the collection electrode capacitance. The novel SDF circuit eliminates the contribution of the input transistor to C_e_f_f, reduces the routing contribution if additional shielding is introduced, provides a way to estimate the capacitance of the sensor itself, and has a voltage gain closer to unity than the standard SF. The SDF circuit has a somewhat larger area with a somewhat smaller bandwidth, but this is acceptable in most cases. A test chip, manufactured in a 180 nm CMOS image sensor process, implements small prototype pixel matrices in different flavors to compare the standard SF to the novel SF and to the novel SF with additional shielding. The effective sensing node capacitance was measured using a "5"5Fe source. Increasing reverse substrate bias from −1 V to −6 V reduces C_e_f_f by 38% and the equivalent noise charge (ENC) by 22% for the

Active pixel sensor with intra-pixel charge transfer

Science.gov (United States)

Fossum, Eric R. (Inventor); Mendis, Sunetra (Inventor); Kemeny, Sabrina E. (Inventor)

2004-01-01

An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node.

RAPS: an innovative active pixel for particle detection integrated in CMOS technology

International Nuclear Information System (INIS)

Passeri, Daniele; Placidi, Pisana; Verducci, Leonardo; Ciampolini, Paolo; Matrella, Guido; Marras, Alessandro; Bilei, G.M.

2004-01-01

In this paper we discuss some design, implementation and test issues, with respect to the development of the RAPS01 chip in the framework of the Radiation Active Pixel Sensors (RAPS) INFN project. The project aimed at verifying feasibility of smart, high-resolution pixel arrays with a fully standard, submicron CMOS technology for particle detection purposes. Layout optimization of the pixel, including sensitive element and local read and amplification circuits has been carried out. Different basic pixel schemes and read-out options have been proposed and devised. Chip fabrication has been completed and test phase is now under way: to this purpose a suitable test environment has been devised and test strategies have been planned

Pixel front-end development in 65 nm CMOS technology

International Nuclear Information System (INIS)

Havránek, M; Hemperek, T; Kishishita, T; Krüger, H; Wermes, N

2014-01-01

Luminosity upgrade of the LHC (HL-LHC) imposes severe constraints on the detector tracking systems in terms of radiation hardness and capability to cope with higher hit rates. One possible way of keeping track with increasing luminosity is the usage of more advanced technologies. Ultra deep sub-micron CMOS technologies allow a design of complex and high speed electronics with high integration density. In addition, these technologies are inherently radiation hard. We present a prototype of analog pixel front-end integrated circuit designed in 65 nm CMOS technology with applications oriented towards the ATLAS Pixel Detector upgrade. The aspects of ultra deep sub-micron design and performance of the analog pixel front-end circuits will be discussed

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.

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...

Characterization of pixel sensor designed in 180 nm SOI CMOS technology

Science.gov (United States)

Benka, T.; Havranek, M.; Hejtmanek, M.; Jakovenko, J.; Janoska, Z.; Marcisovska, M.; Marcisovsky, M.; Neue, G.; Tomasek, L.; Vrba, V.

2018-01-01

A new type of X-ray imaging Monolithic Active Pixel Sensor (MAPS), X-CHIP-02, was developed using a 180 nm deep submicron Silicon On Insulator (SOI) CMOS commercial technology. Two pixel matrices were integrated into the prototype chip, which differ by the pixel pitch of 50 μm and 100 μm. The X-CHIP-02 contains several test structures, which are useful for characterization of individual blocks. The sensitive part of the pixel integrated in the handle wafer is one of the key structures designed for testing. The purpose of this structure is to determine the capacitance of the sensitive part (diode in the MAPS pixel). The measured capacitance is 2.9 fF for 50 μm pixel pitch and 4.8 fF for 100 μm pixel pitch at -100 V (default operational voltage). This structure was used to measure the IV characteristics of the sensitive diode. In this work, we report on a circuit designed for precise determination of sensor capacitance and IV characteristics of both pixel types with respect to X-ray irradiation. The motivation for measurement of the sensor capacitance was its importance for the design of front-end amplifier circuits. The design of pixel elements, as well as circuit simulation and laboratory measurement techniques are described. The experimental results are of great importance for further development of MAPS sensors in this technology.

A module concept for the upgrades of the ATLAS pixel system using the novel SLID-ICV vertical integration technology

CERN Document Server

Beimforde, M; Macchiolo, A; Moser, H G; Nisius, R; Richter, R H; Weigell, P; 10.1088/1748-0221/5/12/C12025

2010-01-01

The presented R&D activity is focused on the development of a new pixel module concept for the foreseen upgrades of the ATLAS detector towards the Super LHC employing thin n-in-p silicon sensors together with a novel vertical integration technology. A first set of pixel sensors with active thicknesses of 75 μm and 150 μm has been produced using a thinning technique developed at the Max-Planck-Institut für Physik (MPP) and the MPI Semiconductor Laboratory (HLL). Charge Collection Efficiency (CCE) measurements of these sensors irradiated with 26 MeV protons up to a particle fluence of 1016neqcm−2 have been performed, yielding higher values than expected from the present radiation damage models. The novel integration technology, developed by the Fraunhofer Institut EMFT, consists of the Solid-Liquid InterDiffusion (SLID) interconnection, being an alternative to the standard solder bump-bonding, and Inter-Chip Vias (ICVs) for routing signals vertically through electronics. This allows for extracting the ...

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.

Gain Scheduling of Observer-Based Controllers with Integral Action

DEFF Research Database (Denmark)

Trangbæk, Klaus; Stoustrup, Jakob; Bendtsen, Jan Dimon

2006-01-01

 This paper presents a method for continuous gain scheduling of  observer-based controllers with integral action. Given two stabilising controllers for a given system, explicit state space formulae are presented, allowing to change gradually from one  controller to the other while preserving...

Experimental characterization of a 10 μW 55 μm-pitch FPN-compensated CMOS digital pixel sensor for X-ray imagers

Energy Technology Data Exchange (ETDEWEB)

Figueras, Roger, E-mail: roger.figueras@imb-cnm.csic.es [Institut de Microelectrònica de Barcelona IMB-CNM(CSIC), Bellaterra (Spain); Martínez, Ricardo; Terés, Lluís [Institut de Microelectrònica de Barcelona IMB-CNM(CSIC), Bellaterra (Spain); Serra-Graells, Francisco [Institut de Microelectrònica de Barcelona IMB-CNM(CSIC), Bellaterra (Spain); Department of Microelectronics and Electronic Systems, Universitat Autònoma de Barcelona, Bellaterra (Spain)

2014-10-11

This paper presents experimental results obtained from both electrical and radiation tests of a new room-temperature digital pixel sensor (DPS) circuit specifically optimized for digital direct X-ray imaging. The 10 μW 55 μm-pitch CMOS active pixel circuit under test includes self-bias capability, built-in test, selectable e{sup −}/h{sup +} collection, 10-bit charge-integration A/D conversion, individual gain tuning for fixed pattern noise (FPN) cancellation, and digital-only I/O interface, which make it suitable for 2D modular chip assemblies in large and seamless sensing areas. Experimental results for this DPS architecture in 0.18 μm 1P6M CMOS technology are reported, returning good performance in terms of linearity, 2ke{sub rms}{sup −} of ENC, inter-pixel crosstalk below 0.5 LSB, 50 Mbps of I/O speed, and good radiation response for its use in digital X-ray imaging.

CMOS Active-Pixel Image Sensor With Simple Floating Gates

Science.gov (United States)

Fossum, Eric R.; Nakamura, Junichi; Kemeny, Sabrina E.

1996-01-01

Experimental complementary metal-oxide/semiconductor (CMOS) active-pixel image sensor integrated circuit features simple floating-gate structure, with metal-oxide/semiconductor field-effect transistor (MOSFET) as active circuit element in each pixel. Provides flexibility of readout modes, no kTC noise, and relatively simple structure suitable for high-density arrays. Features desirable for "smart sensor" applications.

The Pixels find their way to the heart of ATLAS

CERN Multimedia

Kevin Einsweiler

Since the last e-news article on the Pixel Detector in December 2006, there has been much progress. At that time, we were just about to receive the Beryllium beampipe, and to integrate the innermost layer of the Pixel Detector around it. This innermost layer is referred to as the B-layer because of the powerful role it plays in finding the secondary vertices that are the key signature for the presence of b-quarks, and with somewhat greater difficulty, c-quarks and tau leptons. The integration of the central 7m long beampipe into the Pixel Detector was completed in December, and the B-layer was successfully integrated around it. In January this year, we had largely completed the central 1.5m long detector, including the three barrel layers and the three disk layers on each end of the barrel. Although this region contains all of the 80 million readout channels, it cannot be integrated into the Inner Detector without additional services and infrastructure. Therefore, the next step was to add the Service Panels...

RD Collaboration Proposal: Development of pixel readout integrated circuits for extreme rate and radiation

CERN Document Server

Chistiansen, J (CERN)

2013-01-01

This proposal describes a new RD collaboration to develop the next genrration of hybrid pixel readout chips for use in ATLAS and CMS PHase 2 upgrades. extrapolation of hybrid pixel technology to the HL-LHC presents major challenges on several fronts. Challenges include: smaller pixels to resolve tracks in boosted jets, much higher hit rates (1-2 GHz/cm2 ), unprecedented radiation tolerance (10 MGy), much higher output bandwidth, and large IC format with low power consumption in order to instrument large areas while keeping the material budget low. This collaboration is specifically focused on design of hybrid pixel readout chips, and not on more general chip design or on other aspects of hybrid pixel technology. Participants include 7 institutes on ATLAS and 7 on CMS, plus 2 on both experiments.

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...

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)

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

AN INTEGRATED PHOTOGRAMMETRIC AND PHOTOCLINOMETRIC APPROACH FOR PIXEL-RESOLUTION 3D MODELLING OF LUNAR SURFACE

Directory of Open Access Journals (Sweden)

W. C. Liu

2018-04-01

Full Text Available High-resolution 3D modelling of lunar surface is important for lunar scientific research and exploration missions. Photogrammetry is known for 3D mapping and modelling from a pair of stereo images based on dense image matching. However dense matching may fail in poorly textured areas and in situations when the image pair has large illumination differences. As a result, the actual achievable spatial resolution of the 3D model from photogrammetry is limited by the performance of dense image matching. On the other hand, photoclinometry (i.e., shape from shading is characterised by its ability to recover pixel-wise surface shapes based on image intensity and imaging conditions such as illumination and viewing directions. More robust shape reconstruction through photoclinometry can be achieved by incorporating images acquired under different illumination conditions (i.e., photometric stereo. Introducing photoclinometry into photogrammetric processing can therefore effectively increase the achievable resolution of the mapping result while maintaining its overall accuracy. This research presents an integrated photogrammetric and photoclinometric approach for pixel-resolution 3D modelling of the lunar surface. First, photoclinometry is interacted with stereo image matching to create robust and spatially well distributed dense conjugate points. Then, based on the 3D point cloud derived from photogrammetric processing of the dense conjugate points, photoclinometry is further introduced to derive the 3D positions of the unmatched points and to refine the final point cloud. The approach is able to produce one 3D point for each image pixel within the overlapping area of the stereo pair so that to obtain pixel-resolution 3D models. Experiments using the Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC NAC images show the superior performances of the approach compared with traditional photogrammetric technique. The results and findings from this

The modulation of neural gain facilitates a transition between functional segregation and integration in the brain.

Science.gov (United States)

Shine, James M; Aburn, Matthew J; Breakspear, Michael; Poldrack, Russell A

2018-01-29

Cognitive function relies on a dynamic, context-sensitive balance between functional integration and segregation in the brain. Previous work has proposed that this balance is mediated by global fluctuations in neural gain by projections from ascending neuromodulatory nuclei. To test this hypothesis in silico, we studied the effects of neural gain on network dynamics in a model of large-scale neuronal dynamics. We found that increases in neural gain directed the network through an abrupt dynamical transition, leading to an integrated network topology that was maximal in frontoparietal 'rich club' regions. This gain-mediated transition was also associated with increased topological complexity, as well as increased variability in time-resolved topological structure, further highlighting the potential computational benefits of the gain-mediated network transition. These results support the hypothesis that neural gain modulation has the computational capacity to mediate the balance between integration and segregation in the brain. © 2018, Shine et al.

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

Investigation of properties of novel silicon pixel assemblies employing thin n-in-p sensors and 3D-integration

International Nuclear Information System (INIS)

Weigell, Philipp

2013-01-01

Until the end of the 2020 decade the LHC programme will be defining the high energy frontier of particle physics. During this time, three upgrade steps of the accelerator are currently planned to further increase the luminosity and energy reach. In the course of these upgrades the specifications of several parts of the current LHC detectors will be exceeded. Especially, the innermost tracking detectors are challenged by the increasing track densities and the radiation damage. This thesis focuses on the implications for the ATLAS experiment. Here, around 2021/2, after having collected an integrated luminosity of around 300 fb -1 , the silicon and gas detector components of the inner tracker will reach the end of their lifetime and will need to be replaced to ensure sufficient performance for continued running - especially if the luminosity is raised to about 5 x 10 35 cm -2 s -1 as currently planned. An all silicon inner detector is foreseen to be installed. This upgrade demands cost effective pixel assemblies with a minimal material budget, a larger active area fraction as compared to the current detectors, and a higher granularity. Furthermore, the assemblies must be able to withstand received fluences up to 2 . 10 16 n eq /cm 2 . A new pixel assembly concept answering the challenges posed by the high instantaneous luminosities is investigated in this thesis. It employs five novel technologies, namely n-in-p pixel sensors, thin pixel sensors, slim edges with or without implanted sensor sides, and 3D-integration incorporating a new interconnection technology, named Solid Liquid InterDiffusion (SLID) as well as Inter-Chip-Vias (ICVs). n-in-p sensors are cost-effective, since they only need patterned processing on one side. Their performance before and after irradiation is investigated and compared to results obtained with currently used n-in-n sensors. Reducing the thickness of the sensors lowers the amount of multiple scattering within the tracking system and leads

Investigation of properties of novel silicon pixel assemblies employing thin n-in-p sensors and 3D-integration

Energy Technology Data Exchange (ETDEWEB)

Weigell, Philipp

2013-01-15

Until the end of the 2020 decade the LHC programme will be defining the high energy frontier of particle physics. During this time, three upgrade steps of the accelerator are currently planned to further increase the luminosity and energy reach. In the course of these upgrades the specifications of several parts of the current LHC detectors will be exceeded. Especially, the innermost tracking detectors are challenged by the increasing track densities and the radiation damage. This thesis focuses on the implications for the ATLAS experiment. Here, around 2021/2, after having collected an integrated luminosity of around 300 fb{sup -1}, the silicon and gas detector components of the inner tracker will reach the end of their lifetime and will need to be replaced to ensure sufficient performance for continued running - especially if the luminosity is raised to about 5 x 10{sup 35} cm{sup -2}s{sup -1} as currently planned. An all silicon inner detector is foreseen to be installed. This upgrade demands cost effective pixel assemblies with a minimal material budget, a larger active area fraction as compared to the current detectors, and a higher granularity. Furthermore, the assemblies must be able to withstand received fluences up to 2 . 10{sup 16} n{sub eq}/cm{sup 2}. A new pixel assembly concept answering the challenges posed by the high instantaneous luminosities is investigated in this thesis. It employs five novel technologies, namely n-in-p pixel sensors, thin pixel sensors, slim edges with or without implanted sensor sides, and 3D-integration incorporating a new interconnection technology, named Solid Liquid InterDiffusion (SLID) as well as Inter-Chip-Vias (ICVs). n-in-p sensors are cost-effective, since they only need patterned processing on one side. Their performance before and after irradiation is investigated and compared to results obtained with currently used n-in-n sensors. Reducing the thickness of the sensors lowers the amount of multiple scattering

Characterisation of individual pixel efficiency in the PILATUS II sensor

Energy Technology Data Exchange (ETDEWEB)

Schubert, A., E-mail: aschub@physics.unimelb.edu.a [School of Physics, University of Melbourne, Parkville, 3010 (Australia); CRCBID Cooperative Research Centre for Biomedical Imaging, Bundoora, Victoria 3083 (Australia); Centre for PET, Austin Hospital, Heidelberg, Victoria 3084 (Australia); O' Keefe, G.J. [Centre for PET, Austin Hospital, Heidelberg, Victoria 3084 (Australia); School of Physics, University of Melbourne, Parkville, 3010 (Australia); Sobott, B.A. [School of Physics, University of Melbourne, Parkville, 3010 (Australia); CRCBID Cooperative Research Centre for Biomedical Imaging, Bundoora, Victoria 3083 (Australia); Kirby, N.M. [Australian Synchrotron, Clayton, Victoria 3168 (Australia); Rassool, R.P. [School of Physics, University of Melbourne, Parkville, 3010 (Australia); CRCBID Cooperative Research Centre for Biomedical Imaging, Bundoora, Victoria 3083 (Australia)

2010-11-15

Synchrotron applications such as protein crystallography and small-angle X-ray scattering (SAXS) demand precise knowledge of detector pixel efficiency for data corrections. Current techniques used to determine detector efficiency are only applicable for the specific set-up for which the calibration is performed. Here the effect of comparator thresholding on pixel efficiency for PILATUS is presented for standard amplifier and shaper gain settings, allowing users to make necessary corrections to their intensity data for various threshold settings without requiring repeated empirical calibrations. A three-dimensional TCAD simulation of the sensor is also presented and is used to confirm the experimental result.

Active Pixel Sensors: Are CCD's Dinosaurs?

Science.gov (United States)

Fossum, Eric R.

1993-01-01

Charge-coupled devices (CCD's) are presently the technology of choice for most imaging applications. In the 23 years since their invention in 1970, they have evolved to a sophisticated level of performance. However, as with all technologies, we can be certain that they will be supplanted someday. In this paper, the Active Pixel Sensor (APS) technology is explored as a possible successor to the CCD. An active pixel is defined as a detector array technology that has at least one active transistor within the pixel unit cell. The APS eliminates the need for nearly perfect charge transfer -- the Achilles' heel of CCDs. This perfect charge transfer makes CCD's radiation 'soft,' difficult to use under low light conditions, difficult to manufacture in large array sizes, difficult to integrate with on-chip electronics, difficult to use at low temperatures, difficult to use at high frame rates, and difficult to manufacture in non-silicon materials that extend wavelength response.

Design Considerations for Area-Constrained In-Pixel Photon Counting in Medipix3

CERN Document Server

Wong, W; Campbell, M; Heijne, E H M; Llopart, X; Tlustos, L

2008-01-01

Hybrid pixel detectors process impinging photons using front-end electronics electrically connected to a segmented sensor via solder bumps. This allows for complex in-pixel processing while maintaining 100% fill factor. Medipix3 is a single photon processing chip whose 55 μm x 55 μm pixels contain analog charge-processing circuits, inter-pixel routing, and digital blocks. While a standard digital design flow would use logic gates from a standard cell library, the integration of multiple functions and configurations within the compact area of the Medipix3 pixel requires a full-custom manual layout. This work describes the various area-saving design strategies which were employed to optimize the use of available space in the digital section of the Medipix3 pixel.

FE-I4 Firmware Development and Integration with FELIX for the Pixel Detector

CERN Document Server

Yadav, Amitabh; Sharma, Abhishek; CERN. Geneva. EP Department

2017-01-01

CERN has planned a series of upgrades for the LHC. The last in this current series of planned upgrades is designated the HL-LHC. At the same time, the ATLAS Experiment will be extensively changed to meet the challenges of this upgrade (termed as the “Phase-II” upgrade). The Inner Detector will be completely rebuilt for the phase-II. The TRT, SCT and Pixel will be replaced by the all-silicon tracker, termed as the Inner Tracker (ITk). The read-out of this future ITk detector is an engineering challenge for the routing of services and quality of the data. This document describes the FPGA firmware development that integrates the GBT, Elink and Rx-Tx Cores for communication between the FE-I4 modules and the FELIX read-out system.

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.

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.

ATLAS Pixel IBL: Stave Quality Assurance

CERN Document Server

The ATLAS collaboration

2014-01-01

For Run 2 of the LHC a fourth innermost Pixel Detector layer on a smaller radius beam pipe has been installed in the ATLAS Detector to add redundancy against radiation damage of the current Pixel Detector and to ensure a high quality tracking and b-tagging performance of the Inner Detector over the coming years until the High Luminosity Upgrade. State of the art components have been produced and assembled onto support structures known as staves over the last two years. In total, 20 staves have been built and qualified in a designated Quality Assurance setup at CERN of which 14 have been integrated onto the beam pipe. Results from the testing are presented.

Optimization of CMOS active pixels for high resolution digital radiography

International Nuclear Information System (INIS)

Kim, Young Soo

2007-02-01

CMOS image sensors have poorer performance compared to conventional charge coupled devices (CCDs). Since CMOS Active Pixel Sensors (APSs) in general have higher temporal noise, higher dark current, smaller full well charge capacitance, and lower spectral response, they cannot provide the same wide dynamic range and superior signal-to-noise ratio as CCDs. In view of electronic noise, the main source for the CMOS APS is the pixel, along with other signal processing blocks such as row and column decoder, analog signal processor (ASP), analog-to-digital converter (ADC), and timing and control logic circuitry. Therefore, it is important and necessary to characterize noise of the active pixels in CMOS APSs. We developed our theoretical noise model to account for the temporal noise in active pixels, and then found out the optimum design parameters such as fill actor, each size of the three transistors (source follower, row selection transistor, bias transistor) comprising active pixels, bias current, and load capacitance that can have the maximum signal-to-noise ratio. To develop the theoretical noise model in active pixels, we considered the integration noise of the photodiode and the readout noise of the transistors related to readout. During integration, the shot noise due to the dark current and photocurrent, during readout, the thermal and flicker noise were considered. The developed model can take the input variables such as photocurrent, capacitance of the photodiode, integration time, transconductance of the transistors, channel resistance of the transistors, gate-to-source capacitance of the follower, and load capacitance etc. To validate our noise model, two types of test structures have been realized. Firstly, four types of photodiodes (n_d_i_f_f_u_s_i_o_n/p_s_u_b_s_t_r_a_t_e, n_w_e_l_l/p_s_u_b_s_t_r_a_t_e, n_d_i_f_f_u_s_i_o_n/p_e_p_i_t_a_x_i_a_l/p_s_u_b_s_t_r_a_t_e, n_w_e_l_l/p_e_p_i_t_a_x_i_a_l/p_s_u_b_s_t_r_a_t_e) used in CMOS active pixels were fabricated

Insertable B-Layer integration in the ATLAS experiment and development of future 3D silicon pixel sensors

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00371528; Røhne, Ole

This work has two distinct objectives: the development of software for the integration of the Insertable B-Layer (IBL) in the ATLAS offline software framework and the study of the performance of 3D silicon sensors produced by SINTEF for future silicon pixel detectors. The former task consists in the implementation of the IBL byte stream converter. This offline tool performs the decoding of the binary-formatted data coming from the detector into information (e.g. hit position and Time over Threshold) that is stored in a format used in the reconstruction data flow. It also encodes the information extracted from simulations into a simulated IBL byte stream. The tool has been successfully used since the beginning of the LHC Run II data taking. The experimental work on SINTEF 3D sensors was performed in the framework of the development of pixel sensors for the next generation of tracking detectors. Preliminary tests on SINTEF 3D sensors showed that the majority of these devices suffers from high leakage currents, ...

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.

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.

CMOS Active-Pixel Image Sensor With Intensity-Driven Readout

Science.gov (United States)

Langenbacher, Harry T.; Fossum, Eric R.; Kemeny, Sabrina

1996-01-01

Proposed complementary metal oxide/semiconductor (CMOS) integrated-circuit image sensor automatically provides readouts from pixels in order of decreasing illumination intensity. Sensor operated in integration mode. Particularly useful in number of image-sensing tasks, including diffractive laser range-finding, three-dimensional imaging, event-driven readout of sparse sensor arrays, and star tracking.

A differential low-voltage high gain current-mode integrated RF receiver front-end

Energy Technology Data Exchange (ETDEWEB)

Wang Chunhua; Ma Minglin; Sun Jingru; Du Sichun; Guo Xiaorong; He Haizhen, E-mail: wch1227164@sina.com [School of Information Science and Technology, Hunan University, Changsha 410082 (China)

2011-02-15

A differential low-voltage high gain current-mode integrated RF front end for an 802.11b WLAN is proposed. It contains a differential transconductance low noise amplifier (G{sub m}-LNA) and a differential current-mode down converted mixer. The single terminal of the G{sub m}-LNA contains just one MOS transistor, two capacitors and two inductors. The gate-source shunt capacitors, C{sub x1} and C{sub x2}, can not only reduce the effects of gate-source C{sub gs} on resonance frequency and input-matching impedance, but they also enable the gate inductance L{sub g1,2} to be selected at a very small value. The current-mode mixer is composed of four switched current mirrors. Adjusting the ratio of the drain channel sizes of the switched current mirrors can increase the gain of the mixer and accordingly increase the gain of RF receiver front-end. The RF front-end operates under 1 V supply voltage. The receiver RFIC was fabricated using a chartered 0.18 {mu}m CMOS process. The integrated RF receiver front-end has a measured power conversion gain of 17.48 dB and an input referred third-order intercept point (IIP3) of -7.02 dBm. The total noise figure is 4.5 dB and the power is only 14 mW by post-simulations. (semiconductor integrated circuits)

Integrated all optical transmodulator circuits with non-linear gain elements and tunable optical fibers

NARCIS (Netherlands)

Kuindersma, P.I.; Leijtens, X.J.M.; Zantvoort, van J.H.C.; Waardt, de H.

2012-01-01

We characterize integrated InP circuits for high speed ‘all-optical’ signal processing. Single chip circuits act as optical transistors. Transmodulation is performed by non-linear gain sections. Integrated tunable filters give signal equalization in time domain.

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

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.

Study of the CMS Phase 1 Pixel Pilot Blade Reconstruction

CERN Document Server

CMS Collaboration

2017-01-01

The silicon pixel detector is the innermost component of the CMS tracking system. It was replaced in March 2017 with an upgraded one, called the Phase 1 upgrade detector. During Long Shutdown 1, a third disk was inserted into the present forward pixel detector with eight prototype blades constructed using a new digital read-out chip architecture and a prototype readout chain. Testing the performance of these pilot modules enabled us to gain experience with the Phase 1 upgrade modules. In this document, the data reconstruction with the pilot system is presented. The hit finding efficiency and residual of these new modules is also shown, and how these observables were used to adjust the timing of the pilot blades.

Pixel Experiments

DEFF Research Database (Denmark)

Petersen, Kjell Yngve; Søndergaard, Karin; Augustesen, Christina

2015-01-01

Pixel Experiments The term pixel is traditionally defined as any of the minute elements that together constitute a larger context or image. A pixel has its own form and is the smallest unit seen within a larger structure. In working with the potentials of LED technology in architectural lighting...... for using LED lighting in lighting design practice. The speculative experiments that have been set-up have aimed to clarify the variables that can be used as parameters in the design of lighting applications; including, for example, the structuring and software control of light. The experiments also...... elucidate and exemplify already well-known problems in relation to the experience of vertical and horizontal lighting. Pixel Experiments exist as a synergy between speculative test setups and lighting design in practice. This book is one of four books that is published in connection with the research...

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...

Hard X-ray test and evaluation of a prototype 32x32 pixel gallium-arsenide array

International Nuclear Information System (INIS)

Erd, C.; Owens, A.; Brammertz, G.; Bavdaz, M.; Peacock, A.; Laemsae, V.; Nenonen, S.; Andersson, H.; Haack, N.

2002-01-01

We report X-ray measurements on a prototype 1.1 cm 2 , 32x32 GaAs pixel array with a pixel size of 350x350 μm 2 produced to assess the technological feasibility of making large area, almost Fano-limited arrays, which operate near room temperature. Measurements were carried out on four widely separated pixels both in our laboratories and using monochromatic X-ray pencil beams at the HASYLAB synchrotron research facility in Hamburg, Germany. The pixels were found to be very uniform both in their energy and spatial responses. For example, typical energy resolutions of ∼280 eV at 10.5 keV, rising to ∼560 eV at 60 keV were achieved. The corresponding resolutions measured under full-pixel illumination were found to be the same within statistics, indicating uniform crystallinity and stoichiometry. Likewise, by scanning a 15 keV, 15x15 μm 2 beam across the entire surface of each of the pixels, the gain uniformity across the pixels (and by implication the entire array) was determined to be statistically flat

Using Multilayered Substrate Integrated Waveguide to Design Microwave Gain Equalizer

Directory of Open Access Journals (Sweden)

Yongfei Wang

2014-01-01

Full Text Available This paper presents the design and experiment of a novel microwave gain equalizer based on the substrate integrated waveguide (SIW technique. The proposed equalizer is formed by an SIW loaded by SIW resonators, which has very compact structure and can compensate for gain slope of microwave systems. Equivalent circuit analysis is given about the proposed structure for a better insight into the structure’s response. A Ku-Band equalizer with four SIW resonators is simulated and fabricated with a multilayer printed circuit board process. The measured results show good performance and agreement with the simulated results; an attenuation slope of −4.5 dB over 12.5–13.5 GHz is reached with a size reduction of 76%.

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

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

Development of Pixel Front-End Electronics using Advanced Deep Submicron CMOS Technologies

CERN Document Server

Havránek, Miroslav; Dingfelder, Jochen

The content of this thesis is oriented on the R&D; of microelectronic integrated circuits for processing the signal from particle sensors and partially on the sensors themselves. This work is motivated by ongoing upgrades of the ATLAS Pixel Detector at CERN laboratory and by exploration of new technologies for the future experiments in particle physics. Evolution of technologies for the fabrication of microelectronic circuits follows Moore’s laws. Transistors become smaller and electronic chips reach higher complexity. Apart from this, silicon foundries become more open to smaller customers and often provide non-standard process options. Two new directions in pixel technologies are explored in this thesis: design of pixel electronics using ultra deep submicron (65 nm) CMOS technology and Depleted Monolithic Active Pixel Sensors (DMAPS). An independent project concerning the measurement of pixel capacitance with a dedicated measurement chip is a part of this thesis. Pixel capacitance is one of the key pa...

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...

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.

All-passive pixel super-resolution of time-stretch imaging

Science.gov (United States)

Chan, Antony C. S.; Ng, Ho-Cheung; Bogaraju, Sharat C. V.; So, Hayden K. H.; Lam, Edmund Y.; Tsia, Kevin K.

2017-03-01

Based on image encoding in a serial-temporal format, optical time-stretch imaging entails a stringent requirement of state-of-the-art fast data acquisition unit in order to preserve high image resolution at an ultrahigh frame rate — hampering the widespread utilities of such technology. Here, we propose a pixel super-resolution (pixel-SR) technique tailored for time-stretch imaging that preserves pixel resolution at a relaxed sampling rate. It harnesses the subpixel shifts between image frames inherently introduced by asynchronous digital sampling of the continuous time-stretch imaging process. Precise pixel registration is thus accomplished without any active opto-mechanical subpixel-shift control or other additional hardware. Here, we present the experimental pixel-SR image reconstruction pipeline that restores high-resolution time-stretch images of microparticles and biological cells (phytoplankton) at a relaxed sampling rate (≈2-5 GSa/s)—more than four times lower than the originally required readout rate (20 GSa/s) — is thus effective for high-throughput label-free, morphology-based cellular classification down to single-cell precision. Upon integration with the high-throughput image processing technology, this pixel-SR time-stretch imaging technique represents a cost-effective and practical solution for large scale cell-based phenotypic screening in biomedical diagnosis and machine vision for quality control in manufacturing.

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.

Vertically integrated monolithic pixel sensors for charged particle tracking and biomedical imaging

International Nuclear Information System (INIS)

Ratti, L.; Gaioni, L.; Manghisoni, M.; Re, V.; Traversi, G.

2011-01-01

Three-dimensional monolithic pixel sensors have been designed following the same approach that was exploited for the development of the so-called deep N-well (DNW) MAPS in planar CMOS process. The new 3D design relies upon stacking two homogeneous layers fabricated in a 130 nm CMOS technology. One of the two tiers, which are face-to-face bonded, has to be thinned down to about 12μm to expose the through silicon vias connecting the circuits to the back-metal bond pads. As a consequence of the way the two parts of each single chip are designed and fabricated, the prototypes of the 3D monolithic detector will include both samples with a thick substrate underneath the collecting DNW electrode, suitable for charged particle tracking, and samples with a very thin (about 6μm) sensitive volume, which may be used to detect low energy particles in biomedical imaging applications. Device physics simulations have been performed to evaluate the collection properties and detection efficiency of the proposed vertically integrated structures.

Vertically integrated monolithic pixel sensors for charged particle tracking and biomedical imaging

Energy Technology Data Exchange (ETDEWEB)

Ratti, L., E-mail: lodovico.ratti@unipv.it [Universita di Pavia, Dipartimento di Elettronica, Via Ferrata 1, I-27100 Pavia (Italy); INFN, Sezione di Pavia, Via Bassi 6, I-27100 Pavia (Italy); Gaioni, L. [INFN, Sezione di Pavia, Via Bassi 6, I-27100 Pavia (Italy); Manghisoni, M.; Re, V.; Traversi, G. [Universita di Bergamo, Dipartimento di Ingegneria Industriale, Via Marconi 5, I-24044 Dalmine (Italy); INFN, Sezione di Pavia, Via Bassi 6, I-27100 Pavia (Italy)

2011-10-01

Three-dimensional monolithic pixel sensors have been designed following the same approach that was exploited for the development of the so-called deep N-well (DNW) MAPS in planar CMOS process. The new 3D design relies upon stacking two homogeneous layers fabricated in a 130 nm CMOS technology. One of the two tiers, which are face-to-face bonded, has to be thinned down to about 12{mu}m to expose the through silicon vias connecting the circuits to the back-metal bond pads. As a consequence of the way the two parts of each single chip are designed and fabricated, the prototypes of the 3D monolithic detector will include both samples with a thick substrate underneath the collecting DNW electrode, suitable for charged particle tracking, and samples with a very thin (about 6{mu}m) sensitive volume, which may be used to detect low energy particles in biomedical imaging applications. Device physics simulations have been performed to evaluate the collection properties and detection efficiency of the proposed vertically integrated structures.

Thin n-in-p planar pixel modules for the ATLAS upgrade at HL-LHC

International Nuclear Information System (INIS)

Savic, N.; Bergbreiter, L.; Breuer, J.; La Rosa, A.; Macchiolo, A.; Nisius, R.; Terzo, S.

2017-01-01

The ATLAS experiment will undergo a major upgrade of the tracker system in view of the high luminosity phase of the LHC (HL-LHC) foreseen to start around 2025. Thin planar pixel modules are promising candidates to instrument the new pixel system, thanks to the reduced contribution to the material budget and their high charge collection efficiency after irradiation. New designs of the pixel cells, with an optimized biasing structure, have been implemented in n-in-p planar pixel productions with sensor thicknesses of 270 μm. Using beam tests, the gain in hit efficiency is investigated as a function of the received irradiation fluence. The outlook for future thin planar pixel sensor productions will be discussed, with a focus on thin sensors with a thickness of 100 and 150 μm and a novel design with the optimized biasing structure and small pixel cells (50×50 and 25×100 μm"2). These dimensions are foreseen for the new ATLAS read-out chip in 65 nm CMOS technology and the fine segmentation will represent a challenge for the tracking in the forward region of the pixel system at HL-LHC. To predict the performance of 50×50 μm"2 pixels at high η, FE-I4 compatible planar pixel sensors have been studied before and after irradiation in beam tests at high incidence angle with respect to the short pixel direction. Results on cluster shapes, charge collection- and hit efficiency will be shown.

Thin n-in-p planar pixel modules for the ATLAS upgrade at HL-LHC

Energy Technology Data Exchange (ETDEWEB)

Savic, N., E-mail: natascha.savic@mpp.mpg.de; Bergbreiter, L.; Breuer, J.; La Rosa, A.; Macchiolo, A.; Nisius, R.; Terzo, S.

2017-02-11

The ATLAS experiment will undergo a major upgrade of the tracker system in view of the high luminosity phase of the LHC (HL-LHC) foreseen to start around 2025. Thin planar pixel modules are promising candidates to instrument the new pixel system, thanks to the reduced contribution to the material budget and their high charge collection efficiency after irradiation. New designs of the pixel cells, with an optimized biasing structure, have been implemented in n-in-p planar pixel productions with sensor thicknesses of 270 μm. Using beam tests, the gain in hit efficiency is investigated as a function of the received irradiation fluence. The outlook for future thin planar pixel sensor productions will be discussed, with a focus on thin sensors with a thickness of 100 and 150 μm and a novel design with the optimized biasing structure and small pixel cells (50×50 and 25×100 μm{sup 2}). These dimensions are foreseen for the new ATLAS read-out chip in 65 nm CMOS technology and the fine segmentation will represent a challenge for the tracking in the forward region of the pixel system at HL-LHC. To predict the performance of 50×50 μm{sup 2} pixels at high η, FE-I4 compatible planar pixel sensors have been studied before and after irradiation in beam tests at high incidence angle with respect to the short pixel direction. Results on cluster shapes, charge collection- and hit efficiency will be shown.

Characterization of active CMOS pixel sensors on high resistive substrate

Energy Technology Data Exchange (ETDEWEB)

Hirono, Toko; Hemperek, Tomasz; Huegging, Fabian; Krueger, Hans; Rymaszewski, Piotr; Wermes, Norbert [Physikalisches Institut, Universitaet Bonn, Bonn (Germany)

2016-07-01

Active CMOS pixel sensors are very attractive as radiation imaging pixel detector because they do not need cost-intensive fine pitch bump bonding. High radiation tolerance and time resolution are required to apply those sensors to upcoming particle physics experiments. To achieve these requirements, the active CMOS pixel sensors were developed on high resistive substrates. Signal charges are collected faster by drift in high resistive substrates than in standard low resistive substrates yielding also a higher radiation tolerance. A prototype of the active CMOS pixel sensor has been fabricated in the LFoundry 150 nm CMOS process on 2 kΩcm substrate. This prototype chip was thinned down to 300 μm and the backside has been processed and can contacted by an aluminum contact. The breakdown voltage is around -115 V, and the depletion width has been measured to be as large as 180 μm at a bias voltage of -110 V. Gain and noise of the readout circuitry agree with the designed values. Performance tests in the lab and test beam have been done before and after irradiation with X-rays and neutrons. In this presentation, the measurement results of the active CMOS prototype sensors are shown.

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.

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.

ATLAS ITk and new pixel sensors technologies

CERN Document Server

Gaudiello, A

2016-01-01

During the 2023–2024 shutdown, the Large Hadron Collider (LHC) will be upgraded to reach an instantaneous luminosity up to 7×10$^{34}$ cm$^{−2}$s$^{−1}$. This upgrade of the accelerator is called High-Luminosity LHC (HL-LHC). The ATLAS detector will be changed to meet the challenges of HL-LHC: an average of 200 pile-up events in every bunch crossing, and an integrated luminosity of 3000 fb $^{−1}$ over ten years. The HL-LHC luminosity conditions are too extreme for the current silicon (pixel and strip) detectors and straw tube transition radiation tracker (TRT) of the current ATLAS tracking system. Therefore the ATLAS inner tracker is being completely rebuilt for data-taking and the new system is called Inner Tracker (ITk). During this upgrade the TRT will be removed in favor of an all-new all-silicon tracker composed only by strip and pixel detectors. An overview of new layouts in study will be reported and the new pixel sensor technologies in development will be explained.

Hot pixel generation in active pixel sensors: dosimetric and micro-dosimetric response

Science.gov (United States)

Scheick, Leif; Novak, Frank

2003-01-01

The dosimetric response of an active pixel sensor is analyzed. heavy ions are seen to damage the pixel in much the same way as gamma radiation. The probability of a hot pixel is seen to exhibit behavior that is not typical with other microdose effects.

CMOS monolithic active pixel sensors for high energy physics

Energy Technology Data Exchange (ETDEWEB)

Snoeys, W., E-mail: walter.snoeys@cern.ch

2014-11-21

Monolithic pixel detectors integrating sensor matrix and readout in one piece of silicon are only now starting to make their way into high energy physics. Two major requirements are radiation tolerance and low power consumption. For the most extreme radiation levels, signal charge has to be collected by drift from a depletion layer onto a designated collection electrode without losing the signal charge elsewhere in the in-pixel circuit. Low power consumption requires an optimization of Q/C, the ratio of the collected signal charge over the input capacitance [1]. Some solutions to combine sufficient Q/C and collection by drift require exotic fabrication steps. More conventional solutions up to now require a simple in-pixel readout circuit. Both high voltage CMOS technologies and Monolithic Active Pixel Sensors (MAPS) technologies with high resistivity epitaxial layers offer high voltage diodes. The choice between the two is not fundamental but more a question of how much depletion can be reached and also of availability and cost. This paper tries to give an overview.

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

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...

Development of pixel front-end electronics using advanced deep submicron CMOS technologies

International Nuclear Information System (INIS)

Havranek, Miroslav

2014-09-01

The content of this thesis is oriented on the R and D of microelectronic integrated circuits for processing the signal from particle sensors and partially on the sensors themselves. This work is motivated by ongoing upgrades of the ATLAS Pixel Detector at CERN laboratory and by exploration of new technologies for the future experiments in particle physics. Evolution of technologies for the fabrication of microelectronic circuits follows Moore's laws. Transistors become smaller and electronic chips reach higher complexity. Apart from this, silicon foundries become more open to smaller customers and often provide non-standard process options. Two new directions in pixel technologies are explored in this thesis: design of pixel electronics using ultra deep submicron (65 nm) CMOS technology and Depleted Monolithic Active Pixel Sensors (DMAPS). An independent project concerning the measurement of pixel capacitance with a dedicated measurement chip is a part of this thesis. Pixel capacitance is one of the key parameters for design of the pixel front-end electronics and thus it is closely related to the content of the thesis. The theoretical background, aspects of chip design, performance of chip prototypes and prospect for design of large pixel chips are comprehensively described in five chapters of the thesis.

Development of pixel front-end electronics using advanced deep submicron CMOS technologies

Energy Technology Data Exchange (ETDEWEB)

Havranek, Miroslav

2014-09-15

The content of this thesis is oriented on the R and D of microelectronic integrated circuits for processing the signal from particle sensors and partially on the sensors themselves. This work is motivated by ongoing upgrades of the ATLAS Pixel Detector at CERN laboratory and by exploration of new technologies for the future experiments in particle physics. Evolution of technologies for the fabrication of microelectronic circuits follows Moore's laws. Transistors become smaller and electronic chips reach higher complexity. Apart from this, silicon foundries become more open to smaller customers and often provide non-standard process options. Two new directions in pixel technologies are explored in this thesis: design of pixel electronics using ultra deep submicron (65 nm) CMOS technology and Depleted Monolithic Active Pixel Sensors (DMAPS). An independent project concerning the measurement of pixel capacitance with a dedicated measurement chip is a part of this thesis. Pixel capacitance is one of the key parameters for design of the pixel front-end electronics and thus it is closely related to the content of the thesis. The theoretical background, aspects of chip design, performance of chip prototypes and prospect for design of large pixel chips are comprehensively described in five chapters of the thesis.

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.

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.

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.

Active pixel sensor having intra-pixel charge transfer with analog-to-digital converter

Science.gov (United States)

Fossum, Eric R. (Inventor); Mendis, Sunetra K. (Inventor); Pain, Bedabrata (Inventor); Nixon, Robert H. (Inventor); Zhou, Zhimin (Inventor)

2003-01-01

An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node and an analog-to-digital converter formed in the substrate connected to the output of the readout circuit.

Development of a 750x750 pixels CMOS imager sensor for tracking applications

Science.gov (United States)

Larnaudie, Franck; Guardiola, Nicolas; Saint-Pé, Olivier; Vignon, Bruno; Tulet, Michel; Davancens, Robert; Magnan, Pierre; Corbière, Franck; Martin-Gonthier, Philippe; Estribeau, Magali

2017-11-01

Solid-state optical sensors are now commonly used in space applications (navigation cameras, astronomy imagers, tracking sensors...). Although the charge-coupled devices are still widely used, the CMOS image sensor (CIS), which performances are continuously improving, is a strong challenger for Guidance, Navigation and Control (GNC) systems. This paper describes a 750x750 pixels CMOS image sensor that has been specially designed and developed for star tracker and tracking sensor applications. Such detector, that is featuring smart architecture enabling very simple and powerful operations, is built using the AMIS 0.5μm CMOS technology. It contains 750x750 rectangular pixels with 20μm pitch. The geometry of the pixel sensitive zone is optimized for applications based on centroiding measurements. The main feature of this device is the on-chip control and timing function that makes the device operation easier by drastically reducing the number of clocks to be applied. This powerful function allows the user to operate the sensor with high flexibility: measurement of dark level from masked lines, direct access to the windows of interest… A temperature probe is also integrated within the CMOS chip allowing a very precise measurement through the video stream. A complete electro-optical characterization of the sensor has been performed. The major parameters have been evaluated: dark current and its uniformity, read-out noise, conversion gain, Fixed Pattern Noise, Photo Response Non Uniformity, quantum efficiency, Modulation Transfer Function, intra-pixel scanning. The characterization tests are detailed in the paper. Co60 and protons irradiation tests have been also carried out on the image sensor and the results are presented. The specific features of the 750x750 image sensor such as low power CMOS design (3.3V, power consumption<100mW), natural windowing (that allows efficient and robust tracking algorithms), simple proximity electronics (because of the on

Time projection chambers with integrated pixels and their application to fast neutron detection and dark matter searches

Energy Technology Data Exchange (ETDEWEB)

Seong, I.S., E-mail: issung83@gmail.com; Beamer, K.; Hedges, M.T.; Jaegle, I.; Rosen, M.D.; Ross, S.J.; Thorpe, T.N.; Vahsen, S.E.; Yamaoka, J.

2013-12-21

We present our most recent work on the use of integrated silicon pixel electronics to read out gas-filled Time Projection Chambers (TPCs). Such detectors have great promise to measure the direction and energy of neutral particles via nuclear recoils that ionize the gas. We report on ongoing studies and refinement of the first prototype constructed at the University of Hawaii. We present data on the detection of alpha particles and fast neutrons using Ar:CO{sub 2} (70:30) and He:CO{sub 2} (70:30) gas, respectively. We also present plans and sensitivity estimates for a future Dark Matter search based on the technology under study.

From hybrid to CMOS pixels ... a possibility for LHC's pixel future?

International Nuclear Information System (INIS)

Wermes, N.

2015-01-01

Hybrid pixel detectors have been invented for the LHC to make tracking and vertexing possible at all in LHC's radiation intense environment. The LHC pixel detectors have meanwhile very successfully fulfilled their promises and R and D for the planned HL-LHC upgrade is in full swing, targeting even higher ionising doses and non-ionising fluences. In terms of rate and radiation tolerance hybrid pixels are unrivaled. But they have disadvantages as well, most notably material thickness, production complexity, and cost. Meanwhile also active pixel sensors (DEPFET, MAPS) have become real pixel detectors but they would by far not stand the rates and radiation faced from HL-LHC. New MAPS developments, so-called DMAPS (depleted MAPS) which are full CMOS-pixel structures with charge collection in a depleted region have come in the R and D focus for pixels at high rate/radiation levels. This goal can perhaps be realised exploiting HV technologies, high ohmic substrates and/or SOI based technologies. The paper covers the main ideas and some encouraging results from prototyping R and D, not hiding the difficulties

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...

Upgrade of the BOC for the ATLAS Pixel Insertable B-Layer

CERN Document Server

Dopke, J; Heima, T; Kugel, A; Mattig, P; Schroer, N; Zeitnitz, C

2009-01-01

The phase 1 upgrade of the ATLAS [1] pixel detector will be done by inserting a fourth pixel layer together with a new beampipe into the recent three layer detector. This new detector, the Insertable B-Layer (IBL) should be integrated into the recent pixel system with as few changes in services as possible, but deliver some advantages over the recent system. One of those advantages will be a new data transmission link from the detector modules to the off-detector electronics, requiring a re-design of the electro-optical converters on the off-detector side. First ideas of how to implement those, together with some ideas to reduce cost by increasing the systems throughput are discussed.

Integrated parabolic nanolenses on MicroLED color pixels

Science.gov (United States)

Demory, Brandon; Chung, Kunook; Katcher, Adam; Sui, Jingyang; Deng, Hui; Ku, Pei-Cheng

2018-04-01

A parabolic nanolens array coupled to the emission of a nanopillar micro-light emitting diode (LED) color pixel is shown to reduce the far field divergence. For a blue wavelength LED, the total emission is 95% collimated within a 0.5 numerical aperture zone, a 3.5x improvement over the same LED without a lens structure. This corresponds to a half-width at half-maximum (HWHM) line width reduction of 2.85 times. Using a resist reflow and etchback procedure, the nanolens array dimensions and parabolic shape are formed. Experimental measurement of the far field emission shows a HWHM linewidth reduction by a factor of 2x, reducing the divergence over the original LED.

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.

CMOS VLSI Active-Pixel Sensor for Tracking

Science.gov (United States)

Pain, Bedabrata; Sun, Chao; Yang, Guang; Heynssens, Julie

2004-01-01

An architecture for a proposed active-pixel sensor (APS) and a design to implement the architecture in a complementary metal oxide semiconductor (CMOS) very-large-scale integrated (VLSI) circuit provide for some advanced features that are expected to be especially desirable for tracking pointlike features of stars. The architecture would also make this APS suitable for robotic- vision and general pointing and tracking applications. CMOS imagers in general are well suited for pointing and tracking because they can be configured for random access to selected pixels and to provide readout from windows of interest within their fields of view. However, until now, the architectures of CMOS imagers have not supported multiwindow operation or low-noise data collection. Moreover, smearing and motion artifacts in collected images have made prior CMOS imagers unsuitable for tracking applications. The proposed CMOS imager (see figure) would include an array of 1,024 by 1,024 pixels containing high-performance photodiode-based APS circuitry. The pixel pitch would be 9 m. The operations of the pixel circuits would be sequenced and otherwise controlled by an on-chip timing and control block, which would enable the collection of image data, during a single frame period, from either the full frame (that is, all 1,024 1,024 pixels) or from within as many as 8 different arbitrarily placed windows as large as 8 by 8 pixels each. A typical prior CMOS APS operates in a row-at-a-time ( grolling-shutter h) readout mode, which gives rise to exposure skew. In contrast, the proposed APS would operate in a sample-first/readlater mode, suppressing rolling-shutter effects. In this mode, the analog readout signals from the pixels corresponding to the windows of the interest (which windows, in the star-tracking application, would presumably contain guide stars) would be sampled rapidly by routing them through a programmable diagonal switch array to an on-chip parallel analog memory array. The

Design and realisation of integrated circuits for the readout of pixel sensors in high-energy physics and biomedical imaging

Energy Technology Data Exchange (ETDEWEB)

Peric, I.

2004-08-01

Radiation tolerant pixel-readout chip for the ATLAS pixel detector has been designed, implemented in a deep-submicron CMOS technology and successfully tested. The chip contains readout-channels with complex analog and digital circuits. Chip for steering of the DEPFET active-pixel matrix has been implemented in a high-voltage CMOS technology. The chip contains channels which generate fast sequences of high-voltage signals. Detector containing this chip has been successfully tested. Pixel-readout test chip for an X-ray imaging pixel sensor has been designed, implemented in a CMOS technology and tested. Pixel-readout channels are able to simultaneously count the signals generated by passage of individual photons and to sum the total charge generated during exposure time. (orig.)

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.)

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.

Photodiode area effect on performance of X-ray CMOS active pixel sensors

Science.gov (United States)

Kim, M. S.; Kim, Y.; Kim, G.; Lim, K. T.; Cho, G.; Kim, D.

2018-02-01

Compared to conventional TFT-based X-ray imaging devices, CMOS-based X-ray imaging sensors are considered next generation because they can be manufactured in very small pixel pitches and can acquire high-speed images. In addition, CMOS-based sensors have the advantage of integration of various functional circuits within the sensor. The image quality can also be improved by the high fill-factor in large pixels. If the size of the subject is small, the size of the pixel must be reduced as a consequence. In addition, the fill factor must be reduced to aggregate various functional circuits within the pixel. In this study, 3T-APS (active pixel sensor) with photodiodes of four different sizes were fabricated and evaluated. It is well known that a larger photodiode leads to improved overall performance. Nonetheless, if the size of the photodiode is > 1000 μm2, the degree to which the sensor performance increases as the photodiode size increases, is reduced. As a result, considering the fill factor, pixel-pitch > 32 μm is not necessary to achieve high-efficiency image quality. In addition, poor image quality is to be expected unless special sensor-design techniques are included for sensors with a pixel pitch of 25 μm or less.

Thin pixel development for the SuperB silicon vertex tracker

Energy Technology Data Exchange (ETDEWEB)

Rizzo, G., E-mail: giuliana.rizzo@pi.infn.it [INFN-Pisa and Universita di Pisa (Italy); Avanzini, C.; Batignani, G.; Bettarini, S.; Bosi, F.; Ceccanti, M.; Cenci, R.; Cervelli, A.; Crescioli, F.; Dell' Orso, M.; Forti, F.; Giannetti, P.; Giorgi, M.A. [INFN-Pisa and Universita di Pisa (Italy); Lusiani, A. [Scuola Normale Superiore and INFN-Pisa (Italy); Gregucci, S.; Mammini, P.; Marchiori, G.; Massa, M.; Morsani, F.; Neri, N. [INFN-Pisa and Universita di Pisa (Italy); and others

2011-09-11

The high luminosity SuperB asymmetric e{sup +}e{sup -} collider, to be built near the INFN National Frascati Laboratory in Italy, has been designed to deliver a luminosity greater than 10{sup 36} cm{sup -2} s{sup -1} with moderate beam currents and a reduced center of mass boost with respect to earlier B-Factories. An improved vertex resolution is required for precise time-dependent measurements and the SuperB Silicon Vertex Tracker will be equipped with an innermost layer of small radius (about 1.5 cm), resolution of 10-15{mu}m in both coordinates, low material budget (<1% X0), and able to withstand a background rate of several tens of MHz/cm{sup 2}. The ambitious goal of designing a thin pixel device with these stringent requirements is being pursued with specific R and D programs on different technologies: hybrid pixels, CMOS MAPS and pixel sensors developed with vertical integration technology. The latest results on the various pixel options for the SuperB SVT will be presented.

Novel micropixel avalanche photodiodes (MAPD) with superhigh pixel density

International Nuclear Information System (INIS)

Anfimov, N.; Chirikov-Zorin, I.; Dovlatov, A.

2010-01-01

In many detectors based on scintillators the photomultiplier tubes (PMTs) are used as photodetectors. At present photodiodes are finding wide application. Solid state photodetectors allow operation in strong magnetic fields that are often present in applications, e.g., some calorimeters operating near magnets, combined PET and MRT, etc. The photon detection efficiency (PDE) of photodiodes may reach values a few times higher than that of PMTs. Also, they are rigid, compact and have relatively low operating voltage. In the last few years Micropixel Avalanche PhotoDiodes (MAPDs) have been developed and started to be used. The MAPD combines a lot of advantages of semiconductor photodetectors and has a high gain, which is close to that of the PMT. Yet, they have some disadvantages, and one of them is a limited dynamic range that corresponds to a total number of pixels. The novel deep microwell MAPD with high pixel density produced by Zecotek Company partially avoids this disadvantage. In this paper characteristics of these photodetectors are presented in comparison with the PMT characteristics. The results refer to measurements of the gain, PDE, cross-talks, photon counting and applications: beam test results of two different 'Shashlyk' EM calorimeters for COMPASS (CERN) and NICA-MPD (JINR) with the MAPD readout and a possibility of using the MAPD in PET

Fabrication of X-ray Microcalorimeter Focal Planes Composed of Two Distinct Pixel Types

Science.gov (United States)

Wassell, Edward J.; Adams, Joseph S.; Bandler, Simon R.; Betancour-Martinez, Gabriele L; Chiao, Meng P.; Chang, Meng Ping; Chervenak, James A.; Datesman, Aaron M.; Eckart, Megan E.; Ewin, Audrey J.;

Evaluation of color encodings for high dynamic range pixels

Science.gov (United States)

Boitard, Ronan; Mantiuk, Rafal K.; Pouli, Tania

2015-03-01

Traditional Low Dynamic Range (LDR) color spaces encode a small fraction of the visible color gamut, which does not encompass the range of colors produced on upcoming High Dynamic Range (HDR) displays. Future imaging systems will require encoding much wider color gamut and luminance range. Such wide color gamut can be represented using floating point HDR pixel values but those are inefficient to encode. They also lack perceptual uniformity of the luminance and color distribution, which is provided (in approximation) by most LDR color spaces. Therefore, there is a need to devise an efficient, perceptually uniform and integer valued representation for high dynamic range pixel values. In this paper we evaluate several methods for encoding colour HDR pixel values, in particular for use in image and video compression. Unlike other studies we test both luminance and color difference encoding in a rigorous 4AFC threshold experiments to determine the minimum bit-depth required. Results show that the Perceptual Quantizer (PQ) encoding provides the best perceptual uniformity in the considered luminance range, however the gain in bit-depth is rather modest. More significant difference can be observed between color difference encoding schemes, from which YDuDv encoding seems to be the most efficient.

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...

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.

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...

High resolution phoswich gamma-ray imager utilizing monolithic MPPC arrays with submillimeter pixelized crystals

Science.gov (United States)

Kato, T.; Kataoka, J.; Nakamori, T.; Kishimoto, A.; Yamamoto, S.; Sato, K.; Ishikawa, Y.; Yamamura, K.; Kawabata, N.; Ikeda, H.; Kamada, K.

2013-05-01

We report the development of a high spatial resolution tweezers-type coincidence gamma-ray camera for medical imaging. This application consists of large-area monolithic Multi-Pixel Photon Counters (MPPCs) and submillimeter pixelized scintillator matrices. The MPPC array has 4 × 4 channels with a three-side buttable, very compact package. For typical operational gain of 7.5 × 105 at + 20 °C, gain fluctuation over the entire MPPC device is only ± 5.6%, and dark count rates (as measured at the 1 p.e. level) amount to acrylic light guide measuring 1 mm thick, and with summing operational amplifiers that compile the signals into four position-encoded analog outputs being used for signal readout. Spatial resolution of 1.1 mm was achieved with the coincidence imaging system using a 22Na point source. These results suggest that the gamma-ray imagers offer excellent potential for applications in high spatial medical imaging.

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...

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.

Evaluation of testing strategies for the radiation tolerant ATLAS n **+-in-n pixel sensor

CERN Document Server

Klaiber Lodewigs, Jonas M

2003-01-01

The development of particle tracker systems for high fluence environments in new high-energy physics experiments raises new challenges for the development, manufacturing and reliable testing of radiation tolerant components. The ATLAS pixel detector for use at the LHC, CERN, is designed to cover an active sensor area of 1.8 m**2 with 1.1 multiplied by 10 **8 read-out channels usable for a particle fluence up to 10 **1**5 cm**-**2 (1 MeV neutron equivalent) and an ionization dose up to 500 kGy of mainly charged hadron radiation. To cope with such a harsh environment the ATLAS Pixel Collaboration has developed a radiation hard n **+-in-n silicon pixel cell design with a standard cell size of 50 multiplied by 400 mum**2. Using this design on an oxygenated silicon substrate, sensor production has started in 2001. This contribution describes results gained during the development of testing procedures of the ATLAS pixel sensor and evaluates quality assurance procedures regarding their relevance for detector operati...

Design and realization of a fast low noise electronics for a hybrid pixel X-ray detector dedicated to small animal imaging

International Nuclear Information System (INIS)

Chantepie, B.

2008-12-01

Since the invention of computerized tomography (CT), charge integration detector were widely employed for X-ray biomedical imaging applications. Nevertheless, other options exist. A new technology of direct detection using semiconductors has been developed for high energy physics instrumentation. This new technology, called hybrid pixel detector, works in photon counting mode and allows for selecting the minimum energy of the counted photons. The ImXgam research team at CPPM develops the PIXSCAN demonstrator, a CT-scanner using the hybrid pixel detector XPAD. The aim of this project is to evaluate the improvement in image quality and in dose delivered during X-ray examinations of a small animal. After a first prototype of a hybrid pixel detector XPAD1 proving the feasibility of the project, a complete imager XPAD2 was designed and integrated in the PIXSCAN demonstrator. Since then, with the evolution of microelectronic industry, important improvements are conceivable. To reducing the size of pixels and to improving the energy resolution of detectors, a third design XPAD3 was conceived and will be soon integrated in a second generation of PIXSCAN demonstrator. In this project, my thesis work consisted in taking part to the design of the detector readout electronics, to the characterization of the chips and of the hybrid pixel detectors, and also to the definition of a auto-zeroing architecture for pixels. The first and second chapters present X-ray medical imaging and particle detection with semi-conductors and its modelling. The third chapter deals with the specifications of electronic circuits for imaging applications first for analog pixels then for digital pixels and describes the general architecture of the integrated circuits. The validation tests are presented in the fourth chapter while the last chapter gives an account of expected changes in pixel electronics

A comparison of the accuracy of pixel based and object based classifications of integrated optical and LiDAR data

Science.gov (United States)

Gajda, Agnieszka; Wójtowicz-Nowakowska, Anna

2013-04-01

A comparison of the accuracy of pixel based and object based classifications of integrated optical and LiDAR data Land cover maps are generally produced on the basis of high resolution imagery. Recently, LiDAR (Light Detection and Ranging) data have been brought into use in diverse applications including land cover mapping. In this study we attempted to assess the accuracy of land cover classification using both high resolution aerial imagery and LiDAR data (airborne laser scanning, ALS), testing two classification approaches: a pixel-based classification and object-oriented image analysis (OBIA). The study was conducted on three test areas (3 km2 each) in the administrative area of Kraków, Poland, along the course of the Vistula River. They represent three different dominating land cover types of the Vistula River valley. Test site 1 had a semi-natural vegetation, with riparian forests and shrubs, test site 2 represented a densely built-up area, and test site 3 was an industrial site. Point clouds from ALS and ortophotomaps were both captured in November 2007. Point cloud density was on average 16 pt/m2 and it contained additional information about intensity and encoded RGB values. Ortophotomaps had a spatial resolution of 10 cm. From point clouds two raster maps were generated: intensity (1) and (2) normalised Digital Surface Model (nDSM), both with the spatial resolution of 50 cm. To classify the aerial data, a supervised classification approach was selected. Pixel based classification was carried out in ERDAS Imagine software. Ortophotomaps and intensity and nDSM rasters were used in classification. 15 homogenous training areas representing each cover class were chosen. Classified pixels were clumped to avoid salt and pepper effect. Object oriented image object classification was carried out in eCognition software, which implements both the optical and ALS data. Elevation layers (intensity, firs/last reflection, etc.) were used at segmentation stage due to

Operation of a GEM-TPC with pixel readout

CERN Document Server

Brezina, C; Kaminski, J; Killenberg, M; Krautscheid, T

2012-01-01

A prototype time projection chamber with 26 cm drift length was operated with a short-spaced triple gas electron multiplier (GEM) stack in a setup triggering on cosmic muon tracks. A small part of the anode plane is read out with a CMOS pixel application-specified integrated circuit (ASIC) named Timepix, which provides ultimate readout granularity. Pixel clusters of charge depositions corresponding to single primary electrons are observed and analyzed to reconstruct charged particle tracks. A dataset of several weeks of cosmic ray data is analyzed. The number of clusters per track length is well described by simulation. The obtained single point resolution approaches 50 m at short drift distances and is well reproduced by a simple model of single-electron diffusion.

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.

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...

Pixel Experiments

DEFF Research Database (Denmark)

Petersen, Kjell Yngve; Søndergaard, Karin; Augustesen, Christina

2015-01-01

Pixel Experiments The term pixel is traditionally defined as any of the minute elements that together constitute a larger context or image. A pixel has its own form and is the smallest unit seen within a larger structure. In working with the potentials of LED technology in architectural lighting...... lighting design in practice, one quickly experiences and realises that there are untapped potentials in the attributes of LED technology. In this research, speculative studies have been made working with the attributes of LEDs in architectural contexts, with the ambition to ascertain new strategies...... for using LED lighting in lighting design practice. The speculative experiments that have been set-up have aimed to clarify the variables that can be used as parameters in the design of lighting applications; including, for example, the structuring and software control of light. The experiments also...

Characterization study of an intensified complementary metal-oxide-semiconductor active pixel sensor

Science.gov (United States)

Griffiths, J. A.; Chen, D.; Turchetta, R.; Royle, G. J.

2011-03-01

An intensified CMOS active pixel sensor (APS) has been constructed for operation in low-light-level applications: a high-gain, fast-light decay image intensifier has been coupled via a fiber optic stud to a prototype "VANILLA" APS, developed by the UK based MI3 consortium. The sensor is capable of high frame rates and sparse readout. This paper presents a study of the performance parameters of the intensified VANILLA APS system over a range of image intensifier gain levels when uniformly illuminated with 520 nm green light. Mean-variance analysis shows the APS saturating around 3050 Digital Units (DU), with the maximum variance increasing with increasing image intensifier gain. The system's quantum efficiency varies in an exponential manner from 260 at an intensifier gain of 7.45 × 103 to 1.6 at a gain of 3.93 × 101. The usable dynamic range of the system is 60 dB for intensifier gains below 1.8 × 103, dropping to around 40 dB at high gains. The conclusion is that the system shows suitability for the desired application.

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.

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

Toward VIP-PIX: A Low Noise Readout ASIC for Pixelated CdTe Gamma-Ray Detectors for Use in the Next Generation of PET Scanners.

Science.gov (United States)

Macias-Montero, Jose-Gabriel; Sarraj, Maher; Chmeissani, Mokhtar; Puigdengoles, Carles; Lorenzo, Gianluca De; Martínez, Ricardo

2013-08-01

VIP-PIX will be a low noise and low power pixel readout electronics with digital output for pixelated Cadmium Telluride (CdTe) detectors. The proposed pixel will be part of a 2D pixel-array detector for various types of nuclear medicine imaging devices such as positron-emission tomography (PET) scanners, Compton gamma cameras, and positron-emission mammography (PEM) scanners. Each pixel will include a SAR ADC that provides the energy deposited with 10-bit resolution. Simultaneously, the self-triggered pixel which will be connected to a global time-to-digital converter (TDC) with 1 ns resolution will provide the event's time stamp. The analog part of the readout chain and the ADC have been fabricated with TSMC 0.25 μ m mixed-signal CMOS technology and characterized with an external test pulse. The power consumption of these parts is 200 μ W from a 2.5 V supply. It offers 4 switchable gains from ±10 mV/fC to ±40 mV/fC and an input charge dynamic range of up to ±70 fC for the minimum gain for both polarities. Based on noise measurements, the expected equivalent noise charge (ENC) is 65 e - RMS at room temperature.

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.

Development of pixellated Ir-TESs

International Nuclear Information System (INIS)

Zen, Nobuyuki; Takahashi, Hiroyuki; Kunieda, Yuichi; Dayanthi, Rathnayaka M.T.; Mori, Fumiakira; Fujita, Kaoru; Nakazawa, Masaharu; Fukuda, Daiji; Ohkubo, Masataka

2006-01-01

We have been developing Ir-based pixellated superconducting transition edge sensors (TESs). In the area of material or astronomical applications, the sensor with few eV energy resolution and over 1000 pixels imaging property is desired. In order to achieve this goal, we have been analyzing signals from pixellated TESs. In the case of a 20 pixel array of Ir-TESs, with 45 μmx45 μm pixel sizes, the incident X-ray signals have been classified into 16 groups. We have applied numerical signal analysis. On the one hand, the energy resolution of our pixellated TES is strongly degraded. However, using pulse shape analysis, we can dramatically improve the resolution. Thus, we consider that the pulse signal analysis will lead this device to be used as a practical photon incident position identifying TES

A high efficiency readout architecture for a large matrix of pixels.

Science.gov (United States)

Gabrielli, A.; Giorgi, F.; Villa, M.

2010-07-01

In this work we present a fast readout architecture for silicon pixel matrix sensors that has been designed to sustain very high rates, above 1 MHz/mm2 for matrices greater than 80k pixels. This logic can be implemented within MAPS (Monolithic Active Pixel Sensors), a kind of high resolution sensor that integrates on the same bulk the sensor matrix and the CMOS logic for readout, but it can be exploited also with other technologies. The proposed architecture is based on three main concepts. First of all, the readout of the hits is performed by activating one column at a time; all the fired pixels on the active column are read, sparsified and reset in parallel in one clock cycle. This implies the use of global signals across the sensor matrix. The consequent reduction of metal interconnections improves the active area while maintaining a high granularity (down to a pixel pitch of 40 μm). Secondly, the activation for readout takes place only for those columns overlapping with a certain fired area, thus reducing the sweeping time of the whole matrix and reducing the pixel dead-time. Third, the sparsification (x-y address labeling of the hits) is performed with a lower granularity with respect to single pixels, by addressing vertical zones of 8 pixels each. The fine-grain Y resolution is achieved by appending the zone pattern to the zone address of a hit. We show then the benefits of this technique in presence of clusters. We describe this architecture from a schematic point of view, then presenting the efficiency results obtained by VHDL simulations.

A high efficiency readout architecture for a large matrix of pixels

International Nuclear Information System (INIS)

Gabrielli, A; Giorgi, F; Villa, M

2010-01-01

In this work we present a fast readout architecture for silicon pixel matrix sensors that has been designed to sustain very high rates, above 1 MHz/mm 2 for matrices greater than 80k pixels. This logic can be implemented within MAPS (Monolithic Active Pixel Sensors), a kind of high resolution sensor that integrates on the same bulk the sensor matrix and the CMOS logic for readout, but it can be exploited also with other technologies. The proposed architecture is based on three main concepts. First of all, the readout of the hits is performed by activating one column at a time; all the fired pixels on the active column are read, sparsified and reset in parallel in one clock cycle. This implies the use of global signals across the sensor matrix. The consequent reduction of metal interconnections improves the active area while maintaining a high granularity (down to a pixel pitch of 40 μm). Secondly, the activation for readout takes place only for those columns overlapping with a certain fired area, thus reducing the sweeping time of the whole matrix and reducing the pixel dead-time. Third, the sparsification (x-y address labeling of the hits) is performed with a lower granularity with respect to single pixels, by addressing vertical zones of 8 pixels each. The fine-grain Y resolution is achieved by appending the zone pattern to the zone address of a hit. We show then the benefits of this technique in presence of clusters. We describe this architecture from a schematic point of view, then presenting the efficiency results obtained by VHDL simulations.

How many pixels does it take to make a good 4"×6" print? Pixel count wars revisited

Science.gov (United States)

Kriss, Michael A.

2011-01-01

In the early 1980's the future of conventional silver-halide photographic systems was of great concern due to the potential introduction of electronic imaging systems then typified by the Sony Mavica analog electronic camera. The focus was on the quality of film-based systems as expressed in the number of equivalent number pixels and bits-per-pixel, and how many pixels would be required to create an equivalent quality image from a digital camera. It was found that 35-mm frames, for ISO 100 color negative film, contained equivalent pixels of 12 microns for a total of 18 million pixels per frame (6 million pixels per layer) with about 6 bits of information per pixel; the introduction of new emulsion technology, tabular AgX grains, increased the value to 8 bit per pixel. Higher ISO speed films had larger equivalent pixels, fewer pixels per frame, but retained the 8 bits per pixel. Further work found that a high quality 3.5" x 5.25" print could be obtained from a three layer system containing 1300 x 1950 pixels per layer or about 7.6 million pixels in all. In short, it became clear that when a digital camera contained about 6 million pixels (in a single layer using a color filter array and appropriate image processing) that digital systems would challenge and replace conventional film-based system for the consumer market. By 2005 this became the reality. Since 2005 there has been a "pixel war" raging amongst digital camera makers. The question arises about just how many pixels are required and are all pixels equal? This paper will provide a practical look at how many pixels are needed for a good print based on the form factor of the sensor (sensor size) and the effective optical modulation transfer function (optical spread function) of the camera lens. Is it better to have 16 million, 5.7-micron pixels or 6 million 7.8-micron pixels? How does intrinsic (no electronic boost) ISO speed and exposure latitude vary with pixel size? A systematic review of these issues will

Development of pixellated Ir-TESs

Science.gov (United States)

Zen, Nobuyuki; Takahashi, Hiroyuki; Kunieda, Yuichi; Damayanthi, Rathnayaka M. T.; Mori, Fumiakira; Fujita, Kaoru; Nakazawa, Masaharu; Fukuda, Daiji; Ohkubo, Masataka

2006-04-01

We have been developing Ir-based pixellated superconducting transition edge sensors (TESs). In the area of material or astronomical applications, the sensor with few eV energy resolution and over 1000 pixels imaging property is desired. In order to achieve this goal, we have been analyzing signals from pixellated TESs. In the case of a 20 pixel array of Ir-TESs, with 45 μm×45 μm pixel sizes, the incident X-ray signals have been classified into 16 groups. We have applied numerical signal analysis. On the one hand, the energy resolution of our pixellated TES is strongly degraded. However, using pulse shape analysis, we can dramatically improve the resolution. Thus, we consider that the pulse signal analysis will lead this device to be used as a practical photon incident position identifying TES.

Hybrid Pixel-Based Method for Cardiac Ultrasound Fusion Based on Integration of PCA and DWT

Directory of Open Access Journals (Sweden)

Samaneh Mazaheri

2015-01-01

Full Text Available Medical image fusion is the procedure of combining several images from one or multiple imaging modalities. In spite of numerous attempts in direction of automation ventricle segmentation and tracking in echocardiography, due to low quality images with missing anatomical details or speckle noises and restricted field of view, this problem is a challenging task. This paper presents a fusion method which particularly intends to increase the segment-ability of echocardiography features such as endocardial and improving the image contrast. In addition, it tries to expand the field of view, decreasing impact of noise and artifacts and enhancing the signal to noise ratio of the echo images. The proposed algorithm weights the image information regarding an integration feature between all the overlapping images, by using a combination of principal component analysis and discrete wavelet transform. For evaluation, a comparison has been done between results of some well-known techniques and the proposed method. Also, different metrics are implemented to evaluate the performance of proposed algorithm. It has been concluded that the presented pixel-based method based on the integration of PCA and DWT has the best result for the segment-ability of cardiac ultrasound images and better performance in all metrics.

Amorphous In-Ga-Zn-O thin-film transistor active pixel sensor x-ray imager for digital breast tomosynthesis.

Science.gov (United States)

Zhao, Chumin; Kanicki, Jerzy

2014-09-01

The breast cancer detection rate for digital breast tomosynthesis (DBT) is limited by the x-ray image quality. The limiting Nyquist frequency for current DBT systems is around 5 lp/mm, while the fine image details contained in the high spatial frequency region (>5 lp/mm) are lost. Also today the tomosynthesis patient dose is high (0.67-3.52 mGy). To address current issues, in this paper, for the first time, a high-resolution low-dose organic photodetector/amorphous In-Ga-Zn-O thin-film transistor (a-IGZO TFT) active pixel sensor (APS) x-ray imager is proposed for next generation DBT systems. The indirect x-ray detector is based on a combination of a novel low-cost organic photodiode (OPD) and a cesium iodide-based (CsI:Tl) scintillator. The proposed APS x-ray imager overcomes the difficulty of weak signal detection, when small pixel size and low exposure conditions are used, by an on-pixel signal amplification with a significant charge gain. The electrical performance of a-IGZO TFT APS pixel circuit is investigated by SPICE simulation using modified Rensselaer Polytechnic Institute amorphous silicon (a-Si:H) TFT model. Finally, the noise, detective quantum efficiency (DQE), and resolvability of the complete system are modeled using the cascaded system formalism. The result demonstrates that a large charge gain of 31-122 is achieved for the proposed high-mobility (5-20 cm2/V s) amorphous metal-oxide TFT APS. The charge gain is sufficient to eliminate the TFT thermal noise, flicker noise as well as the external readout circuit noise. Moreover, the low TFT (sensor imager under 1 mR, indicating good image quality under low dose. A threefold reduction of current tomosynthesis dose is expected if proposed technology is combined with an advanced DBT image reconstruction method. The proposed a-IGZO APS x-ray imager with a pixel pitch6.67 lp/mm) and a low dose (<0.4 mGy) in next generation DBT systems.

A new poly-Si TFT compensation pixel circuit employing AC driving mode for AMOLED displays

International Nuclear Information System (INIS)

Song Xiaofeng; Luo Jianguo; Wu Weijing; Peng Junbiao; Zhou Lei; Zhang Lirong

2013-01-01

This paper presents a new poly-Si pixel circuit employing AC driving mode for active matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit, which consists of one driving thin-film transistor (TFT), three switching TFTs, and one storage capacitor, can effectively compensate for the threshold voltage variation in poly-Si and the OLED degradation. As there is no light emission, except for during the emitting period, and a small number of devices used in the proposed pixel circuit, a high contrast ratio and a high pixel aperture ratio can be easily achieved. Simulation results by SMART-SPICE software show that the non-uniformity of the OLED current for the proposed pixel circuit is significantly decreased (< 10%) with an average value of 2.63%, while that of the conventional 2T1C is 103%. Thus the brightness uniformity of AMOLED displays can be improved by using the proposed pixel circuit. (semiconductor integrated circuits)

Experience from design, prototyping and production of a DC–DC conversion powering scheme for the CMS Phase-1 Pixel Upgrade

Energy Technology Data Exchange (ETDEWEB)

Feld, Lutz, E-mail: Lutz.Feld@cern.ch; Karpinski, Waclaw; Klein, Katja; Lipinski, Martin; Preuten, Marius; Rauch, Max; Schmitz, Stefan; Wlochal, Michael

2017-02-11

The CMS pixel detector will be replaced during the technical stop 2016/2017. To allow the new pixel detector to be powered with the legacy cable plant and power supplies, a novel powering scheme based on DC–DC conversion will be employed. After the successful conclusion of an extensive development and prototyping phase, mass production of 1800 DC–DC converters as well as motherboards and other power PCBs has now been completed. This contribution reviews the lessons learned from the development of the power system for the Phase-1 pixel detector, and summarizes the experience gained from the production phase.

A high-resolution and intelligent dead pixel detection scheme for an electrowetting display screen

Science.gov (United States)

Luo, ZhiJie; Luo, JianKun; Zhao, WenWen; Cao, Yang; Lin, WeiJie; Zhou, GuoFu

2018-02-01

Electrowetting display technology is realized by tuning the surface energy of a hydrophobic surface by applying a voltage based on electrowetting mechanism. With the rapid development of the electrowetting industry, how to analyze efficiently the quality of an electrowetting display screen has a very important significance. There are two kinds of dead pixels on the electrowetting display screen. One is that the oil of pixel cannot completely cover the display area. The other is that indium tin oxide semiconductor wire connecting pixel and foil was burned. In this paper, we propose a high-resolution and intelligent dead pixel detection scheme for an electrowetting display screen. First, we built an aperture ratio-capacitance model based on the electrical characteristics of electrowetting display. A field-programmable gate array is used as the integrated logic hub of the system for a highly reliable and efficient control of the circuit. Dead pixels can be detected and displayed on a PC-based 2D graphical interface in real time. The proposed dead pixel detection scheme reported in this work has promise in automating electrowetting display experiments.

A hybrid 3D LIDAR imager based on pixel-by-pixel scanning and DS-OCDMA

Science.gov (United States)

Kim, Gunzung; Eom, Jeongsook; Park, Yongwan

2016-03-01

We propose a new hybrid 3D light detection and ranging (LIDAR) system, which measures a scene with 1280 x 600 pixels at a refresh rate of 60fps. The emitted pulses of each pixel are modulated by direct sequence optical code division multiple access (DS-OCDMA) techniques. The modulated pulses include a unique device identification number, the pixel position in the line, and a checksum. The LIDAR emits the modulated pulses periodically without waiting to receive returning light at the detector. When all the pixels are completely through the process, the travel time, amplitude, width, and speed are used by the pixel-by-pixel scanning LIDAR imager to generate point cloud data as the measured results. We programmed the entire hybrid 3D LIDAR operation in a simulator to observe the functionality accomplished by our proposed model.

Frequency-multiplexed bias and readout of a 16-pixel superconducting nanowire single-photon detector array

Science.gov (United States)

Doerner, S.; Kuzmin, A.; Wuensch, S.; Charaev, I.; Boes, F.; Zwick, T.; Siegel, M.

2017-07-01

We demonstrate a 16-pixel array of microwave-current driven superconducting nanowire single-photon detectors with an integrated and scalable frequency-division multiplexing architecture, which reduces the required number of bias and readout lines to a single microwave feed line. The electrical behavior of the photon-sensitive nanowires, embedded in a resonant circuit, as well as the optical performance and timing jitter of the single detectors is discussed. Besides the single pixel measurements, we also demonstrate the operation of a 16-pixel array with a temporal, spatial, and photon-number resolution.

Hybrid active pixel sensors in infrared astronomy

International Nuclear Information System (INIS)

Finger, Gert; Dorn, Reinhold J.; Meyer, Manfred; Mehrgan, Leander; Stegmeier, Joerg; Moorwood, Alan

2005-01-01

Infrared astronomy is currently benefiting from three main technologies providing high-performance hybrid active pixel sensors. In the near infrared from 1 to 5 μm two technologies, both aiming for buttable 2Kx2K mosaics, are competing, namely InSb and HgCdTe grown by LPE or MBE on Al 2 O 3 , Si or CdZnTe substrates. Blocked impurity band Si:As arrays cover the mid infrared spectral range from 8 to 28 μm. Adaptive optics combined with multiple integral field units feeding high-resolution spectrographs drive the requirements for the array format of infrared sensors used at ground-based infrared observatories. The pixel performance is now approaching fundamental limits. In view of this development, a detection limit for the photon flux of the ideal detector will be derived, depending only on the temperature and the impedance of the detector. It will be shown that this limit is approximated by state of the art infrared arrays for long on-chip integrations. Different detector materials are compared and strategies to populate large focal planes are discussed. The need for the development of small-format low noise sensors for adaptive optics and interferometry will be pointed out

Low complexity pixel-based halftone detection

Science.gov (United States)

Ok, Jiheon; Han, Seong Wook; Jarno, Mielikainen; Lee, Chulhee

2011-10-01

With the rapid advances of the internet and other multimedia technologies, the digital document market has been growing steadily. Since most digital images use halftone technologies, quality degradation occurs when one tries to scan and reprint them. Therefore, it is necessary to extract the halftone areas to produce high quality printing. In this paper, we propose a low complexity pixel-based halftone detection algorithm. For each pixel, we considered a surrounding block. If the block contained any flat background regions, text, thin lines, or continuous or non-homogeneous regions, the pixel was classified as a non-halftone pixel. After excluding those non-halftone pixels, the remaining pixels were considered to be halftone pixels. Finally, documents were classified as pictures or photo documents by calculating the halftone pixel ratio. The proposed algorithm proved to be memory-efficient and required low computation costs. The proposed algorithm was easily implemented using GPU.

Ultra-thin silicon (UTSi) on insulator CMOS transceiver and time-division multiplexed switch chips for smart pixel integration

Science.gov (United States)

Zhang, Liping; Sawchuk, Alexander A.

2001-12-01

We describe the design, fabrication and functionality of two different 0.5 micron CMOS optoelectronic integrated circuit (OEIC) chips based on the Peregrine Semiconductor Ultra-Thin Silicon on insulator technology. The Peregrine UTSi silicon- on-sapphire (SOS) technology is a member of the silicon-on- insulator (SOI) family. The low-loss synthetic sapphire substrate is optically transparent and has good thermal conductivity and coefficient of thermal expansion properties, which meet the requirements for flip-chip bonding of VCSELs and other optoelectronic input-output components. One chip contains transceiver and network components, including four channel high-speed CMOS transceiver modules, pseudo-random bit stream (PRBS) generators, a voltage controlled oscillator (VCO) and other test circuits. The transceiver chips can operate in both self-testing mode and networking mode. An on- chip clock and true-single-phase-clock (TSPC) D-flip-flop have been designed to generate a PRBS at over 2.5 Gb/s for the high-speed transceiver arrays to operate in self-testing mode. In the networking mode, an even number of transceiver chips forms a ring network through free-space or fiber ribbon interconnections. The second chip contains four channel optical time-division multiplex (TDM) switches, optical transceiver arrays, an active pixel detector and additional test devices. The eventual applications of these chips will require monolithic OEICs with integrated optical input and output. After fabrication and testing, the CMOS transceiver array dies will be packaged with 850 nm vertical cavity surface emitting lasers (VCSELs), and metal-semiconductor- metal (MSM) or GaAs p-i-n detector die arrays to achieve high- speed optical interconnections. The hybrid technique could be either wire bonding or flip-chip bonding of the CMOS SOS smart-pixel arrays with arrays of VCSELs and photodetectors onto an optoelectronic chip carrier as a multi-chip module (MCM).

Low-Gain, Low-Noise Integrated Neuronal Amplifier for Implantable Artifact-Reduction Recording System

Directory of Open Access Journals (Sweden)

Abdelhamid Benazzouz

2013-09-01

Full Text Available Brain neuroprostheses for neuromodulation are being designed to monitor the neural activity of the brain in the vicinity of the region being stimulated using a single macro-electrode. Using a single macro-electrode, recent neuromodulation studies show that recording systems with a low gain neuronal amplifier and successive amplifier stages can reduce or reject stimulation artifacts. These systems were made with off-the-shelf components that are not amendable for future implant design. A low-gain, low-noise integrated neuronal amplifier (NA with the capability of recording local field potentials (LFP and spike activity is presented. In vitro and in vivo characterizations of the tissue/electrode interface, with equivalent impedance as an electrical model for recording in the LFP band using macro-electrodes for rodents, contribute to the NA design constraints. The NA occupies 0.15 mm2 and dissipates 6.73 µW, and was fabricated using a 0.35 µm CMOS process. Test-bench validation indicates that the NA provides a mid-band gain of 20 dB and achieves a low input-referred noise of 4 µVRMS. Ability of the NA to perform spike recording in test-bench experiments is presented. Additionally, an awake and freely moving rodent setup was used to illustrate the integrated NA ability to record LFPs, paving the pathway for future implantable systems for neuromodulation.

Integrating pixel- and polygon-based approaches to wildfire risk assessment: Application to a high-value watershed on the Pike and San Isabel National Forests, Colorado, USA

Science.gov (United States)

Matthew P. Thompson; Julie W. Gilbertson-Day; Joe H. Scott

2015-01-01

We develop a novel risk assessment approach that integrates complementary, yet distinct, spatial modeling approaches currently used in wildfire risk assessment. Motivation for this work stems largely from limitations of existing stochastic wildfire simulation systems, which can generate pixel-based outputs of fire behavior as well as polygon-based outputs of simulated...

Novel micropixel avalanche photodiodes (MAPD) with super high pixel density

International Nuclear Information System (INIS)

Anfimov, N.; Chirikov-Zorin, I.; Dovlatov, A.; Gavrishchuk, O.; Guskov, A.; Khovanskiy, N.; Krumshtein, Z.; Leitner, R.; Meshcheryakov, G.; Nagaytsev, A.; Olchevski, A.; Rezinko, T.; Sadovskiy, A.; Sadygov, Z.; Savin, I.; Tchalyshev, V.; Tyapkin, I.; Yarygin, G.; Zerrouk, F.

2011-01-01

In many detectors based on scintillators the photomultiplier tubes (PMTs) are used as photodetectors. At present photodiodes are finding wide application. Solid state photodetectors allow operation in strong magnetic fields that are often present in applications, e.g. some calorimeters operating near magnets, combined PET and MRT, etc. The photon detection efficiency (PDE) of photodiodes may reach values a few times higher than that of PMTs. Also, they are rigid, compact and have relatively low operating voltage. In the last few years Micropixel Avalanche PhotoDiodes (MAPD) have been developed and started to be used. The MAPD combines a lot of advantages of semiconductor photodetectors and has a high gain, which is close to that of the PMT. Yet, they have some disadvantages, and one of them is a limited dynamic range that corresponds to a total number of pixels. The novel deep microwell MAPD with high pixel density produced by the Zecotek Company partially avoids this disadvantage. In this paper characteristics of these photodetectors are presented in comparison with the PMT characteristics. The results refer to measurements of the gain, PDE, cross-talks, photon counting and applications: beam test results of two different 'Shashlyk' EM calorimeters for COMPASS (CERN) and NICA-MPD (JINR) with the MAPD readout and a possibility of using the MAPD in PET.

Comparative study of various pixel photodiodes for digital radiography: Junction structure, corner shape and noble window opening

Science.gov (United States)

Kang, Dong-Uk; Cho, Minsik; Lee, Dae Hee; Yoo, Hyunjun; Kim, Myung Soo; Bae, Jun Hyung; Kim, Hyoungtaek; Kim, Jongyul; Kim, Hyunduk; Cho, Gyuseong

2012-05-01

Recently, large-size 3-transistors (3-Tr) active pixel complementary metal-oxide silicon (CMOS) image sensors have been being used for medium-size digital X-ray radiography, such as dental computed tomography (CT), mammography and nondestructive testing (NDT) for consumer products. We designed and fabricated 50 µm × 50 µm 3-Tr test pixels having a pixel photodiode with various structures and shapes by using the TSMC 0.25-m standard CMOS process to compare their optical characteristics. The pixel photodiode output was continuously sampled while a test pixel was continuously illuminated by using 550-nm light at a constant intensity. The measurement was repeated 300 times for each test pixel to obtain reliable results on the mean and the variance of the pixel output at each sampling time. The sampling rate was 50 kHz, and the reset period was 200 msec. To estimate the conversion gain, we used the mean-variance method. From the measured results, the n-well/p-substrate photodiode, among 3 photodiode structures available in a standard CMOS process, showed the best performance at a low illumination equivalent to the typical X-ray signal range. The quantum efficiencies of the n+/p-well, n-well/p-substrate, and n+/p-substrate photodiodes were 18.5%, 62.1%, and 51.5%, respectively. From a comparison of pixels with rounded and rectangular corners, we found that a rounded corner structure could reduce the dark current in large-size pixels. A pixel with four rounded corners showed a reduced dark current of about 200fA compared to a pixel with four rectangular corners in our pixel sample size. Photodiodes with round p-implant openings showed about 5% higher dark current, but about 34% higher sensitivities, than the conventional photodiodes.

Comparative study of various pixel photodiodes for digital radiography: junction structure, corner shape and noble window opening

Energy Technology Data Exchange (ETDEWEB)

Kang, Dong-Uk; Cho, Min-Sik; Lee, Dae-Hee; Yoo, Hyun-Jun; Kim, Myung-Soo; Bae, Jun-Hyung; Kim, Hyoung-Taek; Kim, Jong-Yul; Kim, Hyun-Duk; Cho, Gyu-Seong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

2012-05-15

Recently, large-size 3-transistors (3-Tr) active pixel complementary metal-oxide silicon (CMOS) image sensors have been being used for medium-size digital X-ray radiography, such as dental computed tomography (CT), mammography and nondestructive testing (NDT) for consumer products. We designed and fabricated 50 μm x 50 μm 3-Tr test pixels having a pixel photodiode with various structures and shapes by using the TSMC 0.25-m standard CMOS process to compare their optical characteristics. The pixel photodiode output was continuously sampled while a test pixel was continuously illuminated by using 550-nm light at a constant intensity. The measurement was repeated 300 times for each test pixel to obtain reliable results on the mean and the variance of the pixel output at each sampling time. The sampling rate was 50 kHz, and the reset period was 200 msec. To estimate the conversion gain, we used the mean-variance method. From the measured results, the n-well/p-substrate photodiode, among 3 photodiode structures available in a standard CMOS process, showed the best performance at a low illumination equivalent to the typical X-ray signal range. The quantum efficiencies of the n+/p-well, n-well/p-substrate, and n+/p-substrate photodiodes were 18.5%, 62.1%, and 51.5%, respectively. From a comparison of pixels with rounded and rectangular corners, we found that a rounded corner structure could reduce the dark current in large-size pixels. A pixel with four rounded corners showed a reduced dark current of about 200 fA compared to a pixel with four rectangular corners in our pixel sample size. Photodiodes with round p-implant openings showed about 5% higher dark current, but about 34% higher sensitivities, than the conventional photodiodes.

Active pixel image sensor with a winner-take-all mode of operation

Science.gov (United States)

Yadid-Pecht, Orly (Inventor); Fossum, Eric R. (Inventor); Mead, Carver (Inventor)

2003-01-01

An integrated CMOS semiconductor imaging device having two modes of operation that can be performed simultaneously to produce an output image and provide information of a brightest or darkest pixel in the image.

A module concept for the upgrades of the ATLAS pixel system using the novel SLID-ICV vertical integration technology

Energy Technology Data Exchange (ETDEWEB)

Beimforde, M; Andricek, L; Macchiolo, A; Moser, H-G; Nisius, R; Richter, R H; Weigell, P, E-mail: Michael.Beimforde@mpp.mpg.de [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805, Muenchen (Germany)

2010-12-15

The presented R and D activity is focused on the development of a new pixel module concept for the foreseen upgrades of the ATLAS detector towards the Super LHC employing thin n-in-p silicon sensors together with a novel vertical integration technology. A first set of pixel sensors with active thicknesses of 75 {mu}m and 150 {mu}m has been produced using a thinning technique developed at the Max-Planck-Institut fuer Physik (MPP) and the MPI Semiconductor Laboratory (HLL). Charge Collection Efficiency (CCE) measurements of these sensors irradiated with 26 MeV protons up to a particle fluence of 10{sup 16}n{sub eq}cm{sup -2} have been performed, yielding higher values than expected from the present radiation damage models. The novel integration technology, developed by the Fraunhofer Institut EMFT, consists of the Solid-Liquid InterDiffusion (SLID) interconnection, being an alternative to the standard solder bump-bonding, and Inter-Chip Vias (ICVs) for routing signals vertically through electronics. This allows for extracting the digitized signals from the back side of the readout chips, avoiding wire-bonding cantilevers at the edge of the devices and thus increases the active area fraction. First interconnections have been performed with wafers containing daisy chains to investigate the efficiency of SLID at wafer-to-wafer and chip-to-wafer level. In a second interconnection process the present ATLAS FE-I3 readout chips were connected to dummy sensor wafers at chip-to-wafer level. Preparations of ICV within the ATLAS readout chips for back side contacting and the future steps towards a full demonstrator module will be presented.

A module concept for the upgrades of the ATLAS pixel system using the novel SLID-ICV vertical integration technology

International Nuclear Information System (INIS)

Beimforde, M; Andricek, L; Macchiolo, A; Moser, H-G; Nisius, R; Richter, R H; Weigell, P

2010-01-01

The presented R and D activity is focused on the development of a new pixel module concept for the foreseen upgrades of the ATLAS detector towards the Super LHC employing thin n-in-p silicon sensors together with a novel vertical integration technology. A first set of pixel sensors with active thicknesses of 75 μm and 150 μm has been produced using a thinning technique developed at the Max-Planck-Institut fuer Physik (MPP) and the MPI Semiconductor Laboratory (HLL). Charge Collection Efficiency (CCE) measurements of these sensors irradiated with 26 MeV protons up to a particle fluence of 10 16 n eq cm -2 have been performed, yielding higher values than expected from the present radiation damage models. The novel integration technology, developed by the Fraunhofer Institut EMFT, consists of the Solid-Liquid InterDiffusion (SLID) interconnection, being an alternative to the standard solder bump-bonding, and Inter-Chip Vias (ICVs) for routing signals vertically through electronics. This allows for extracting the digitized signals from the back side of the readout chips, avoiding wire-bonding cantilevers at the edge of the devices and thus increases the active area fraction. First interconnections have been performed with wafers containing daisy chains to investigate the efficiency of SLID at wafer-to-wafer and chip-to-wafer level. In a second interconnection process the present ATLAS FE-I3 readout chips were connected to dummy sensor wafers at chip-to-wafer level. Preparations of ICV within the ATLAS readout chips for back side contacting and the future steps towards a full demonstrator module will be presented.

FED firmware interface testing with pixel phase 1 emulator

CERN Document Server

Kilpatrick, Matthew

2017-01-01

A hardware emulation of the CMS pixel detector phase 1 upgrade front-end electronics has been developed to test and validate the architecture of the back-end electronics (FED) firmware. The emulation is implemented on a Virtex 6 FPGA on the CERN GLIB uTCA platform, utilizing an 8-way SFP FPGA Mezzanine Card to drive compatible optical transmitters to the back-end electronics at 400 bps. The firmware emulates the complex functions of the phase 1 pixel readout chips (PSI46digv2 and PROC600) and token bit manager ASICs and allows for possible abnormalities that can occur in the output data stream. The emulation implements both fixed data patterns that are used as test vectors and realistic simulated data to drive the readout of the FED at the expected data and trigger rates. Testing software was developed to control the emulator and verify correct transmission of data and exception handling in the FED. An installation has been integrated into the pixel DAQ test system at CMS to be used for fast validation of F...

FED firmware interface testing with pixel phase 1 emulator

CERN Document Server

Kilpatrick, Matthew

2018-01-01

A hardware emulation of the CMS pixel detector phase 1 upgrade front-end electronics has been developed to test and validate the architecture of the back-end electronics (FED) firmware. The emulation is implemented on a Virtex 6 FPGA on the CERN GLIB uTCA platform, utilizing an 8-way SFP FPGA Mezzanine Card to drive compatible optical transmitters to the back-end electronics at 400 bps. The firmware emulates the complex functions of the phase 1 pixel readout chips (PSI46digv2 and PROC600) and token bit manager ASICs and allows for possible abnormalities that can occur in the output data stream. The emulation implements both fixed data patterns that are used as test vectors and realistic simulated data to drive the readout of the FED at the expected data and trigger rates. Testing software was developed to control the emulator and verify correct transmission of data and exception handling in the FED. An installation has been integrated into the pixel DAQ test system at CMS to be used for fast validation of F...

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...

Digital Power Consumption Estimations for CHIPIX65 Pixel Readout Chip

CERN Document Server

Marcotulli, Andrea

2016-01-01

New hybrid pixel detectors with improved resolution capable of dealing with hit rates up to 3 GHz/cm2 will be required for future High Energy Physics experiments in the Large Hadron Collider (LHC) at CERN. Given this, the RD53 collaboration works on the design of the next generation pixel readout chip needed for both the ATLAS and CMS detector phase 2 pixel upgrades. For the RD53 demonstrator chip in 65nm CMOS technology, different architectures are considered. In particular the purpose of this work is estimating the power consumption of the digital architecture of the readout ASIC developed by CHIPIX65 project of the INFN National Scientific Committee. This has been done with modern chip design tools integrated with the VEPIX53 simulation framework that has been developed within the RD53 collaboration in order to assess the performance of the system in very high rate, high energy physics experiments.

Monolithic active pixel sensors (MAPS) in a VLSI CMOS technology

CERN Document Server

Turchetta, R; Manolopoulos, S; Tyndel, M; Allport, P P; Bates, R; O'Shea, V; Hall, G; Raymond, M

2003-01-01

Monolithic Active Pixel Sensors (MAPS) designed in a standard VLSI CMOS technology have recently been proposed as a compact pixel detector for the detection of high-energy charged particle in vertex/tracking applications. MAPS, also named CMOS sensors, are already extensively used in visible light applications. With respect to other competing imaging technologies, CMOS sensors have several potential advantages in terms of low cost, low power, lower noise at higher speed, random access of pixels which allows windowing of region of interest, ability to integrate several functions on the same chip. This brings altogether to the concept of 'camera-on-a-chip'. In this paper, we review the use of CMOS sensors for particle physics and we analyse their performances in term of the efficiency (fill factor), signal generation, noise, readout speed and sensor area. In most of high-energy physics applications, data reduction is needed in the sensor at an early stage of the data processing before transfer of the data to ta...

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 ...

Performance of thin pixel sensors irradiated up to a fluence of 1016neqcm-2 and development of a new interconnection technology for the upgrade of the ATLAS pixel system

International Nuclear Information System (INIS)

Macchiolo, A.; Andricek, L.; Beimforde, M.; Moser, H.-G.; Nisius, R.; Richter, R.H.; Weigell, P.

2011-01-01

A new pixel module concept is presented, where thin sensors and a novel vertical integration technique are combined. This R and D activity is carried out in view of the ATLAS pixel detector upgrades. A first set of n-in-p pixel sensors with active thicknesses of 75 and 150μm has been produced using a thinning technique developed at the Max-Planck-Institut Halbleiterlabor (HLL). Charge Collection Efficiency measurements have been performed, yielding a higher CCE than expected from the present radiation damage models. The interconnection of thin n-in-p pixels to the FE-I3 ATLAS electronics is under way, exploiting the Solid Liquid Interdiffusion (SLID) technique developed by the Fraunhofer Institut EMFT. In addition, preliminary studies aimed at Inter-Chip-Vias (ICV) etching into the FE-I3 electronics are reported. ICVs will be used to route the signals vertically through the read-out chip, to newly created pads on the backside. This should serve as a proof of principle for future four-side tileable pixel assemblies, avoiding the cantilever presently needed in the chip for the wire bonding.

Pixel-Tilecal-MDT Combined Test Beam

CERN Multimedia

B. Di Girolamo

A test with many expectations When an additional week of running (from September 11th to 18th) was allocated for the test-beam, it was decided to give priority to a combined run with the participation of the Pixel, Tilecal and MDT sub-detectors. The integration of these three sub-detectors was possible as they all use the baseline (DAQ-1/EF based) DAQ for test beams (as reported in a previous e-news). The tests and the addition of a common trigger and busy were organized in a short timescale by experts from the three sub-detectors and DAQ/EF. The expectations were many; both looking for problems and finding solutions. The setup The setup, shown in the figure, consisted of the Pixel telescope normally used during the sub-detector tests, two Tilecal barrel modules, two Tilecal extended barrel modules, and six MDT barrel chambers. This fully occupied a length of some 30 meters in the H8 line of the SPS North Area. Each sub-detector used their own specialized front-end electronics. The data collected by modu...

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

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

Study of the CMS Phase-1 Pixel Pilot Blade Reconstruction

CERN Document Server

Vami, Tamas Almos

2017-01-01

The Compact Muon Solenoid (CMS) detector is one of two general-purpose detectors that measure the products of high energy particle interactions in the Large Hadron Collider (LHC) at CERN. The silicon pixel detector is the innermost component of the CMS tracking system. The detector which was in operation between 2009 and 2016 has now been replaced with an upgraded one in the beginning of 2017. During the previous shutdown period of the LHC, a prototype readout system and a third disk was inserted into the old forward pixel detector with eight prototype blades constructed using the new digital read-out chips. Testing the performance of these pilot modules enabled us to gain operational experience with the upgraded detector. In this paper, the reconstruction and analysis of the data taken with the new modules are presented including information on the calibration of the reconstruction software. The hit finding efficiency and track-hit residual distributions are also shown.

Gains from an integrated market for tradable renewable energy credits

International Nuclear Information System (INIS)

Mozumder, Pallab; Marathe, Achla

2004-01-01

Decoupling the environmental attributes of renewable energy (RE) generation from the physical unit of energy is an innovative mechanism for marketing green or renewable power. The introduction of 'Tradable Renewable Energy Credits' (TRECs) allows the green power attributes of energy to be sold or traded separately from the physical unit of energy. Since the green power certificate system removes potential locational and physical bottlenecks, both suppliers and consumers gain flexibility in the marketplace. The TREC is also an efficient tool to meet 'Renewable Portfolio Standard' (RPS) required by different states in the US. This paper discusses the RPS requirements for different states and examines the implications of an integrated TREC market. It offers a competitive setting to the consumers to pay for renewable energy and a cost effective tool to support renewable energy generation [Grace and Wiser, 2002]. This paper also highlights some practical difficulties that should be addressed in order to establish an efficient integrated TREC market

A smart-pixel holographic competitive learning network

Science.gov (United States)

Slagle, Timothy Michael

Neural networks are adaptive classifiers which modify their decision boundaries based on feedback from externally- or internally-generated error signals. Optics is an attractive technology for neural network implementation because it offers the possibility of parallel, nearly instantaneous computation of the weighted neuron inputs by the propagation of light through the optical system. Using current optical device technology, system performance levels of 3 × 1011 connection updates per second can be achieved. This thesis presents an architecture for an optical competitive learning network which offers advantages over previous optical implementations, including smart-pixel-based optical neurons, phase- conjugate self-alignment of a single neuron plane, and high-density, parallel-access weight storage, interconnection, and learning in a volume hologram. The competitive learning algorithm with modifications for optical implementation is described, and algorithm simulations are performed for an example problem. The optical competitive learning architecture is then introduced. The optical system is simulated using the ``beamprop'' algorithm at the level of light propagating through the system components, and results showing competitive learning operation in agreement with the algorithm simulations are presented. The optical competitive learning requires a non-linear, non-local ``winner-take-all'' (WTA) neuron function. Custom-designed smart-pixel WTA neuron arrays were fabricated using CMOS VLSI/liquid crystal technology. Results of laboratory tests of the WTA arrays' switching characteristics, time response, and uniformity are then presented. The system uses a phase-conjugate mirror to write the self-aligning interconnection weight holograms, and energy gain is required from the reflection to minimize erasure of the existing weights. An experimental system for characterizing the PCM response is described. Useful gains of 20 were obtained with a polarization

High resolution phoswich gamma-ray imager utilizing monolithic MPPC arrays with submillimeter pixelized crystals

International Nuclear Information System (INIS)

Kato, T; Kataoka, J; Nakamori, T; Kishimoto, A; Yamamoto, S; Sato, K; Ishikawa, Y; Yamamura, K; Kawabata, N; Ikeda, H; Kamada, K

2013-01-01

We report the development of a high spatial resolution tweezers-type coincidence gamma-ray camera for medical imaging. This application consists of large-area monolithic Multi-Pixel Photon Counters (MPPCs) and submillimeter pixelized scintillator matrices. The MPPC array has 4 × 4 channels with a three-side buttable, very compact package. For typical operational gain of 7.5 × 10 5 at + 20 °C, gain fluctuation over the entire MPPC device is only ± 5.6%, and dark count rates (as measured at the 1 p.e. level) amount to ≤ 400 kcps per channel. We selected Ce-doped (Lu,Y) 2 (SiO 4 )O (Ce:LYSO) and a brand-new scintillator, Ce-doped Gd 3 Al 2 Ga 3 O 12 (Ce:GAGG) due to their high light yield and density. To improve the spatial resolution, these scintillators were fabricated into 15 × 15 matrices of 0.5 × 0.5 mm 2 pixels. The Ce:LYSO and Ce:GAGG scintillator matrices were assembled into phosphor sandwich (phoswich) detectors, and then coupled to the MPPC array along with an acrylic light guide measuring 1 mm thick, and with summing operational amplifiers that compile the signals into four position-encoded analog outputs being used for signal readout. Spatial resolution of 1.1 mm was achieved with the coincidence imaging system using a 22 Na point source. These results suggest that the gamma-ray imagers offer excellent potential for applications in high spatial medical imaging.

High Gain Antenna System Deployment Mechanism Integration, Characterization, and Lessons Learned

Science.gov (United States)

Parong, Fil; Russell, Blair; Garcen, Walter; Rose, Chris; Johnson, Chris; Huber, Craig

2014-01-01

The integration and deployment testing of the High Gain Antenna System for the Global Precipitation Measurement mission is summarized. The HGAS deployment mechanism is described. The gravity negation system configuration and its influence on vertical, ground-based, deployment tests are presented with test data and model predictions. A focus is made on the late discovery and resolution of a potentially mission degrading deployment interference condition. The interaction of the flight deployment mechanism, gravity negation mechanism, and use of dynamic modeling is described and lessons learned presented.

The NUC and blind pixel eliminating in the DTDI application

Science.gov (United States)

Su, Xiao Feng; Chen, Fan Sheng; Pan, Sheng Da; Gong, Xue Yi; Dong, Yu Cui

2013-12-01

AS infrared CMOS Digital TDI (Time Delay and integrate) has a simple structure, excellent performance and flexible operation, it has been used in more and more applications. Because of the limitation of the Production process level, the plane array of the infrared detector has a large NU (non-uniformity) and a certain blind pixel rate. Both of the two will raise the noise and lead to the TDI works not very well. In this paper, for the impact of the system performance, the most important elements are analyzed, which are the NU of the optical system, the NU of the Plane array and the blind pixel in the Plane array. Here a reasonable algorithm which considers the background removal and the linear response model of the infrared detector is used to do the NUC (Non-uniformity correction) process, when the infrared detector array is used as a Digital TDI. In order to eliminate the impact of the blind pixel, the concept of surplus pixel method is introduced in, through the method, the SNR (signal to noise ratio) can be improved and the spatial and temporal resolution will not be changed. Finally we use a MWIR (Medium Ware Infrared) detector to do the experiment and the result proves the effectiveness of the method.

Design of a radiation hard silicon pixel sensor for X-ray science

Energy Technology Data Exchange (ETDEWEB)

Schwandt, Joern

2014-06-15

At DESY Hamburg the European X-ray Free-Electron Laser (EuXFEL) is presently under construction. The EuXFEL has unique properties with respect to X-ray energy, instantaneous intensity, pulse length, coherence and number of pulses/sec. These properties of the EuXFEL pose very demanding requirements for imaging detectors. One of the detector systems which is currently under development to meet these challenges is the Adaptive Gain Integrating Pixel Detector, AGIPD. It is a hybrid pixel-detector system with 1024 x 1024 p{sup +} pixels of dimensions 200 μm x 200 μm, made of 16 p{sup +}nn{sup +}- silicon sensors, each with 10.52 cm x 2.56 cm sensitive area and 500 μm thickness. The particular requirements for the AGIPD are a separation between noise and single photons down to energies of 5 keV, more than 10{sup 4} photons per pixel for a pulse duration of less than 100 fs, negligible pile-up at the EuXFEL repetition rate of 4.5 MHz, operation for X-ray doses up to 1 GGy, good efficiency for X-rays with energies between 5 and 20 keV, and minimal inactive regions at the edges. The main challenge in the sensor design is the required radiation tolerance and high operational voltage, which is required to reduce the so-called plasma effect. This requires a specially optimized sensor. The X-ray radiation damage results in a build-up of oxide charges and interface traps which lead to a reduction of the breakdown voltage, increased leakage current, increased interpixel capacitances and charge losses. Extensive TCAD simulations have been performed to understand the impact of X-ray radiation damage on the detector performance and optimize the sensor design. To take radiation damage into account in the simulation, radiation damage parameters have been determined on MOS capacitors and gate-controlled diodes as function of dose. The optimized sensor design was fabricated by SINTEF. Irradiation tests on test structures and sensors show that the sensor design is radiation hard and

Mass test of AdvanSiD model ASD-NUV3S-P SiliconPMs for the Pixel Timing Counter of the MEG II experiment

Science.gov (United States)

Rossella, M.; Bariani, S.; Barnaba, O.; Cattaneo, P. W.; Cervi, T.; Menegolli, A.; Nardò, R.; Prata, M. C.; Romano, E.; Scagliotti, C.; Simonetta, M.; Vercellati, F.

2017-02-01

The MEG II Timing Counter will measure the positron time of arrival with a resolution of 30 ps relying on two arrays of scintillator pixels read out by 6144 Silicon Photomultipliers (SiPMs) from AdvanSiD. They must be characterized, measuring their breakdown voltage, to assure that the gains of the SiPMs of each pixel are as uniform as possible, to maximize the pixel resolution. To do this an automatic test system that can measure sequentially the parameters of 32 devices has been developed.

Correction of sub-pixel topographical effects on land surface albedo retrieved from geostationary satellite (FengYun-2D) observations

International Nuclear Information System (INIS)

Roupioz, L; Nerry, F; Jia, L; Menenti, M

2014-01-01

The Qinghai-Tibetan Plateau is characterised by a very strong relief which affects albedo retrieval from satellite data. The objective of this study is to highlight the effects of sub-pixel topography and to account for those effects when retrieving land surface albedo from geostationary satellite FengYun-2D (FY-2D) data with 1.25km spatial resolution using the high spatial resolution (30 m) data of the Digital Elevation Model (DEM) from ASTER. The methodology integrates the effects of sub-pixel topography on the estimation of the total irradiance received at the surface, allowing the computation of the topographically corrected surface reflectance. Furthermore, surface albedo is estimated by applying the parametric BRDF (Bidirectional Reflectance Distribution Function) model called RPV (Rahman-Pinty-Verstraete) to the terrain corrected surface reflectance. The results, evaluated against ground measurements collected over several experimental sites on the Qinghai-Tibetan Plateau, document the advantage of integrating the sub-pixel topography effects in the land surface reflectance at 1km resolution to estimate the land surface albedo. The results obtained after using sub-pixel topographic correction are compared with the ones obtained after using pixel level topographic correction. The preliminary results imply that, in highly rugged terrain, the sub-pixel topography correction method gives more accurate results. The pixel level correction tends to overestimate surface albedo

A new design of the gaseous imaging detector: Micro Pixel Chamber

CERN Document Server

Ochi, A; Koishi, S; Tanimori, T; Nagae, T; Nakamura, M

2001-01-01

The novel gaseous detector 'Micro Pixel Chamber (Micro PIC)' has been developed for X-ray, gamma-ray and charged particle imaging. This detector consists of double sided printing circuit board (PCB). The stable operation of Micro PIC is realized by thick substrate and wide anode strips. One of the most outstanding feature is the process of production and the cost. The base technology of producing Micro PIC is same as producing PCB, then detector with large detection area (more than 10 cmx10 cm) can be made by present technology. Our first tests were performed using a 3 cmx3 cm detection area with a readout of 0.4 mm pitch. The gas gain and stability were measured in these tests. The gas gain of 10 sup 4 was obtained using argon ethane (8:2) gas mixture. Also, there was no discharge between anodes and cathodes in the gain of 10 sup 3 during two days of continuous operation. Although some discharges occurred in the higher gain (approximately 10 sup 4), no critical damage on the detector was found.

Design and realization of a fast low noise electronics for a hybrid pixel X-ray detector dedicated to small animal imaging

International Nuclear Information System (INIS)

Chantepie, Benoit

2008-01-01

Since the invention of computerized tomography (CT), charge integration detector were widely employed for X-ray biomedical imaging applications. Nevertheless, other options exist. A new technology of direct detection using semiconductors has been developed for high energy physics instrumentation. This new technology, called hybrid pixel detector, works in photon counting mode and allows for selecting the minimum energy of the counted photons. The imXgam research team at CPPM develops the PIXSCAN demonstrator, a CT-scanner using the hybrid pixel detector XPAD. The aim of this project is to evaluate the improvement on image quality and on dose delivered during X-ray examinations of a small animal. After a first prototype of hybrid pixel detector XPAD1 proving the feasibility of the project, a complete imager XPAD2 was designed and integrated in the PIXSCAN demonstrator. Since then, with the evolution of microelectronic industry, important improvements are conceivable. To reducing the size of pixels and to improving the energy resolution of detectors, a third design XPAD3 was conceived and will be soon integrated in a second generation of PIXSCAN demonstrator. In this project, my thesis's work consisted in taking part to the design of the detector readout electronics, to the characterization of the chips and of the hybrid pixel detectors, and also to the definition of an auto-zeroing architecture for pixels. (author) [fr

Spatial clustering of pixels of a multispectral image

Science.gov (United States)

Conger, James Lynn

2014-08-19

A method and system for clustering the pixels of a multispectral image is provided. A clustering system computes a maximum spectral similarity score for each pixel that indicates the similarity between that pixel and the most similar neighboring. To determine the maximum similarity score for a pixel, the clustering system generates a similarity score between that pixel and each of its neighboring pixels and then selects the similarity score that represents the highest similarity as the maximum similarity score. The clustering system may apply a filtering criterion based on the maximum similarity score so that pixels with similarity scores below a minimum threshold are not clustered. The clustering system changes the current pixel values of the pixels in a cluster based on an averaging of the original pixel values of the pixels in the cluster.

Design and characterization of novel monolithic pixel sensors for the ALICE ITS upgrade

CERN Document Server

Cavicchioli, C; Giubilato, P; Hillemanns, H; Junique, A; Kugathasan, T; Mager, M; Marin Tobon, C A; Martinengo, P; Mattiazzo, S; Mugnier, H; Musa, L; Pantano, D; Rousset, J; Reidt, F; Riedler, P; Snoeys, W; Van Hoorne, J W; Yang, P

2014-01-01

Within the R&D activities for the upgrade of the ALICE Inner Tracking System (ITS), Monolithic Active Pixel Sensors (MAPS) are being developed and studied, due to their lower material budget (~0.3%X0~0.3%X0 in total for each inner layer) and higher granularity (View the MathML source~20μm×20μm pixels) with respect to the present pixel detector. This paper presents the design and characterization results of the Explorer0 chip, manufactured in the TowerJazz 180 nm CMOS Imaging Sensor process, based on a wafer with high-resistivity View the MathML source(ρ>1kΩcm) and 18 μm thick epitaxial layer. The chip is organized in two sub-matrices with different pixel pitches (20 μm and 30 μm), each of them containing several pixel designs. The collection electrode size and shape, as well as the distance between the electrode and the surrounding electronics, are varied; the chip also offers the possibility to decouple the charge integration time from the readout time, and to change the sensor bias. The charge c...

Energy-correction photon counting pixel for photon energy extraction under pulse pile-up

Energy Technology Data Exchange (ETDEWEB)

Lee, Daehee; Park, Kyungjin; Lim, Kyung Taek; Cho, Gyuseong, E-mail: gscho@kaist.ac.kr

2017-06-01

A photon counting detector (PCD) has been proposed as an alternative solution to an energy-integrating detector (EID) in medical imaging field due to its high resolution, high efficiency, and low noise. The PCD has expanded to variety of fields such as spectral CT, k-edge imaging, and material decomposition owing to its capability to count and measure the number and the energy of an incident photon, respectively. Nonetheless, pulse pile-up, which is a superimposition of pulses at the output of a charge sensitive amplifier (CSA) in each PC pixel, occurs frequently as the X-ray flux increases due to the finite pulse processing time (PPT) in CSAs. Pulse pile-up induces not only a count loss but also distortion in the measured X-ray spectrum from each PC pixel and thus it is a main constraint on the use of PCDs in high flux X-ray applications. To minimize these effects, an energy-correction PC (ECPC) pixel is proposed to resolve pulse pile-up without cutting off the PPT by adding an energy correction logic (ECL) via a cross detection method (CDM). The ECPC pixel with a size of 200×200 µm{sup 2} was fabricated by using a 6-metal 1-poly 0.18 µm CMOS process with a static power consumption of 7.2 μW/pixel. The maximum count rate of the ECPC pixel was extended by approximately three times higher than that of a conventional PC pixel with a PPT of 500 nsec. The X-ray spectrum of 90 kVp, filtered by 3 mm Al filter, was measured as the X-ray current was increased using the CdTe and the ECPC pixel. As a result, the ECPC pixel dramatically reduced the energy spectrum distortion at 2 Mphotons/pixel/s when compared to that of the ERCP pixel with the same 500 nsec PPT.

Fully depleted CMOS pixel sensor development and potential applications

Energy Technology Data Exchange (ETDEWEB)

Baudot, J.; Kachel, M. [Universite de Strasbourg, IPHC, 23 rue du Loess 67037 Strasbourg (France); CNRS, UMR7178, 67037 Strasbourg (France)

2015-07-01

low noise figure. Especially, an energy resolution of about 400 eV for 5 keV X-rays was obtained for single pixels. The prototypes have then been exposed to gradually increased fluences of neutrons, from 10{sup 13} to 5x10{sup 14} neq/cm{sup 2}. Again laboratory tests allowed to evaluate the signal over noise persistence on the different pixels implemented. Currently our development mostly targets the detection of soft X-rays, with the ambition to develop a pixel sensor matching counting rates as affordable with hybrid pixel sensors, but with an extended sensitivity to low energy and finer pixel about 25 x 25 μm{sup 2}. The original readout architecture proposed relies on a two tiers chip. The first tier consists of a sensor with a modest dynamic in order to insure low noise performances required by sensitivity. The interconnected second tier chip enhances the read-out speed by introducing massive parallelization. Performances reachable with this strategy combining counting and integration will be detailed. (authors)

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.

Objective guidelines for removing an external fixator after tibial lengthening using pixel value ratio: a pilot study.

Science.gov (United States)

Zhao, Li; Fan, Qing; Venkatesh, K P; Park, Man S; Song, Hae Ryong

2009-12-01

During limb lengthening over an intramedullary nail, decisions regarding external fixator removal and weightbearing depend on the amount of callus seen at the lengthening area on radiographs. However, this method is subjective and objective evaluation of the amount of callus likely would minimize nail or interlocking screw breakage and refracture after fixator removal. We asked how many cortices with full corticalization of the newly formed bone at the lengthening area are needed to allow fixator removal and full weightbearing and how to radiographically determine the stage of corticalization. We retrospectively reviewed 17 patients (34 lengthenings) who underwent bilateral tibial lengthenings over an intramedullary nail. The average gain in length was 7.2 +/- 3.4 cm. We determined the pixel value ratio (ratio of pixel value of regenerate versus the mean pixel value of adjacent bone) of the lengthened area on radiographs. There were no nail or screw breakage and refracture. Partial weightbearing with crutches was permitted when the pixel value ratio was 1 in two cortices and full weightbearing without crutches was permitted when the pixel value ratio was 1 in three cortices. The pixel value ratio on radiographs can be an objective parameter for callus measurement and may provide guidelines for the timing of external fixator removal. We cannot determine from our limited data the minimum pixel value in how many cortices would suggest safe removal, but we can say our criteria were not associated with subsequent refracture.

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...

Performance of a novel wafer scale CMOS active pixel sensor for bio-medical imaging

International Nuclear Information System (INIS)

Esposito, M; Evans, P M; Wells, K; Anaxagoras, T; Konstantinidis, A C; Zheng, Y; Speller, R D; Allinson, N M

2014-01-01

Recently CMOS active pixels sensors (APSs) have become a valuable alternative to amorphous silicon and selenium flat panel imagers (FPIs) in bio-medical imaging applications. CMOS APSs can now be scaled up to the standard 20 cm diameter wafer size by means of a reticle stitching block process. However, despite wafer scale CMOS APS being monolithic, sources of non-uniformity of response and regional variations can persist representing a significant challenge for wafer scale sensor response. Non-uniformity of stitched sensors can arise from a number of factors related to the manufacturing process, including variation of amplification, variation between readout components, wafer defects and process variations across the wafer due to manufacturing processes. This paper reports on an investigation into the spatial non-uniformity and regional variations of a wafer scale stitched CMOS APS. For the first time a per-pixel analysis of the electro-optical performance of a wafer CMOS APS is presented, to address inhomogeneity issues arising from the stitching techniques used to manufacture wafer scale sensors. A complete model of the signal generation in the pixel array has been provided and proved capable of accounting for noise and gain variations across the pixel array. This novel analysis leads to readout noise and conversion gain being evaluated at pixel level, stitching block level and in regions of interest, resulting in a coefficient of variation ⩽1.9%. The uniformity of the image quality performance has been further investigated in a typical x-ray application, i.e. mammography, showing a uniformity in terms of CNR among the highest when compared with mammography detectors commonly used in clinical practice. Finally, in order to compare the detection capability of this novel APS with the technology currently used (i.e. FPIs), theoretical evaluation of the detection quantum efficiency (DQE) at zero-frequency has been performed, resulting in a higher DQE for this

Performance of a novel wafer scale CMOS active pixel sensor for bio-medical imaging.

Science.gov (United States)

Esposito, M; Anaxagoras, T; Konstantinidis, A C; Zheng, Y; Speller, R D; Evans, P M; Allinson, N M; Wells, K

2014-07-07

Recently CMOS active pixels sensors (APSs) have become a valuable alternative to amorphous silicon and selenium flat panel imagers (FPIs) in bio-medical imaging applications. CMOS APSs can now be scaled up to the standard 20 cm diameter wafer size by means of a reticle stitching block process. However, despite wafer scale CMOS APS being monolithic, sources of non-uniformity of response and regional variations can persist representing a significant challenge for wafer scale sensor response. Non-uniformity of stitched sensors can arise from a number of factors related to the manufacturing process, including variation of amplification, variation between readout components, wafer defects and process variations across the wafer due to manufacturing processes. This paper reports on an investigation into the spatial non-uniformity and regional variations of a wafer scale stitched CMOS APS. For the first time a per-pixel analysis of the electro-optical performance of a wafer CMOS APS is presented, to address inhomogeneity issues arising from the stitching techniques used to manufacture wafer scale sensors. A complete model of the signal generation in the pixel array has been provided and proved capable of accounting for noise and gain variations across the pixel array. This novel analysis leads to readout noise and conversion gain being evaluated at pixel level, stitching block level and in regions of interest, resulting in a coefficient of variation ⩽1.9%. The uniformity of the image quality performance has been further investigated in a typical x-ray application, i.e. mammography, showing a uniformity in terms of CNR among the highest when compared with mammography detectors commonly used in clinical practice. Finally, in order to compare the detection capability of this novel APS with the technology currently used (i.e. FPIs), theoretical evaluation of the detection quantum efficiency (DQE) at zero-frequency has been performed, resulting in a higher DQE for this

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.

Depleted Monolithic Pixels (DMAPS) in a 150 nm technology: lab and beam results

International Nuclear Information System (INIS)

Obermann, T.; Hemperek, T.; Hügging, F.; Krüger, H.; Pohl, D.-L.; Wermes, N.; Schwenker, B.

2017-01-01

The fully depleted monolithic active pixel sensor (DMAPS) is a new concept integrating full CMOS circuitry onto a fully depletable silicon substrate wafer. The realization of prototypes of the DMAPS concept relies on the availability of multiple well CMOS processes and high resistive substrates. The CMOS foundry ESPROS Photonics offers both and was chosen for prototyping. Two prototypes, EPCB01 and EPCB02, were developed in a 150 nm process on a high resistive n-type wafer of 50 μm thickness. The prototypes have 352 square pixels of 40 μm pitch and small n-well charge collection node with very low capacitance (n + -implantation size: 5 μm by 5 μm) and about 150 transistors per pixel (CSA and discriminator plus a small digital part).

Application of a new interconnection technology for the ATLAS pixel upgrade at SLHC

CERN Document Server

Macchiolo, A; Beimforde, M; Moser, H G; Nisius, R; Richter, R H

2009-01-01

We present an R&D activity aiming towards a new detector concept in the framework of the ATLAS pixel detector upgrade exploiting a vertical integration technology developed at the Fraunhofer Institute IZMMunich. The Solid-Liquid InterDiffusion (SLID) technique is investigated as an alternative to the bump-bonding process. We also investigate the extraction of the signals from the back of the read-out chip through Inter-Chip-Vias to achieve a higher fraction of active area with respect to the present ATLAS pixel module. We will present the layout and the first results obtained with a production of test-structures designed to investigate the SLID interconnection efficiency as a function of different parameters, i.e. the pixel size and pitch, as well as the planarity of the underlying layers.

New generation of monolithic active pixel sensors for charged particle detection; Developpement d'un capteur de nouvelle generation et son electronique integree pour les collisionneurs futurs

Energy Technology Data Exchange (ETDEWEB)

Deptuch, G

2002-09-01

Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a {sup 55}Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 {mu}m and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 10{sup 12} n/cm{sup 2} and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

Pixelated coatings and advanced IR coatings

Science.gov (United States)

Pradal, Fabien; Portier, Benjamin; Oussalah, Meihdi; Leplan, Hervé

2017-09-01

Reosc developed pixelated infrared coatings on detector. Reosc manufactured thick pixelated multilayer stacks on IR-focal plane arrays for bi-spectral imaging systems, demonstrating high filter performance, low crosstalk, and no deterioration of the device sensitivities. More recently, a 5-pixel filter matrix was designed and fabricated. Recent developments in pixelated coatings, shows that high performance infrared filters can be coated directly on detector for multispectral imaging. Next generation space instrument can benefit from this technology to reduce their weight and consumptions.

Amorphous In–Ga–Zn–O thin-film transistor active pixel sensor x-ray imager for digital breast tomosynthesis

Energy Technology Data Exchange (ETDEWEB)

Zhao, Chumin; Kanicki, Jerzy, E-mail: kanicki@eecs.umich.edu [Solid-State Electronic Laboratory, Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2014-09-15

Purpose: The breast cancer detection rate for digital breast tomosynthesis (DBT) is limited by the x-ray image quality. The limiting Nyquist frequency for current DBT systems is around 5 lp/mm, while the fine image details contained in the high spatial frequency region (>5 lp/mm) are lost. Also today the tomosynthesis patient dose is high (0.67–3.52 mGy). To address current issues, in this paper, for the first time, a high-resolution low-dose organic photodetector/amorphous In–Ga–Zn–O thin-film transistor (a-IGZO TFT) active pixel sensor (APS) x-ray imager is proposed for next generation DBT systems. Methods: The indirect x-ray detector is based on a combination of a novel low-cost organic photodiode (OPD) and a cesium iodide-based (CsI:Tl) scintillator. The proposed APS x-ray imager overcomes the difficulty of weak signal detection, when small pixel size and low exposure conditions are used, by an on-pixel signal amplification with a significant charge gain. The electrical performance of a-IGZO TFT APS pixel circuit is investigated by SPICE simulation using modified Rensselaer Polytechnic Institute amorphous silicon (a-Si:H) TFT model. Finally, the noise, detective quantum efficiency (DQE), and resolvability of the complete system are modeled using the cascaded system formalism. Results: The result demonstrates that a large charge gain of 31–122 is achieved for the proposed high-mobility (5–20 cm{sup 2}/V s) amorphous metal-oxide TFT APS. The charge gain is sufficient to eliminate the TFT thermal noise, flicker noise as well as the external readout circuit noise. Moreover, the low TFT (<10{sup −13} A) and OPD (<10{sup −8} A/cm{sup 2}) leakage currents can further reduce the APS noise. Cascaded system analysis shows that the proposed APS imager with a 75 μm pixel pitch can effectively resolve the Nyquist frequency of 6.67 lp/mm, which can be further improved to ∼10 lp/mm if the pixel pitch is reduced to 50 μm. Moreover, the

Amorphous In–Ga–Zn–O thin-film transistor active pixel sensor x-ray imager for digital breast tomosynthesis

International Nuclear Information System (INIS)

Zhao, Chumin; Kanicki, Jerzy

2014-01-01

Purpose: The breast cancer detection rate for digital breast tomosynthesis (DBT) is limited by the x-ray image quality. The limiting Nyquist frequency for current DBT systems is around 5 lp/mm, while the fine image details contained in the high spatial frequency region (>5 lp/mm) are lost. Also today the tomosynthesis patient dose is high (0.67–3.52 mGy). To address current issues, in this paper, for the first time, a high-resolution low-dose organic photodetector/amorphous In–Ga–Zn–O thin-film transistor (a-IGZO TFT) active pixel sensor (APS) x-ray imager is proposed for next generation DBT systems. Methods: The indirect x-ray detector is based on a combination of a novel low-cost organic photodiode (OPD) and a cesium iodide-based (CsI:Tl) scintillator. The proposed APS x-ray imager overcomes the difficulty of weak signal detection, when small pixel size and low exposure conditions are used, by an on-pixel signal amplification with a significant charge gain. The electrical performance of a-IGZO TFT APS pixel circuit is investigated by SPICE simulation using modified Rensselaer Polytechnic Institute amorphous silicon (a-Si:H) TFT model. Finally, the noise, detective quantum efficiency (DQE), and resolvability of the complete system are modeled using the cascaded system formalism. Results: The result demonstrates that a large charge gain of 31–122 is achieved for the proposed high-mobility (5–20 cm 2 /V s) amorphous metal-oxide TFT APS. The charge gain is sufficient to eliminate the TFT thermal noise, flicker noise as well as the external readout circuit noise. Moreover, the low TFT (<10 −13 A) and OPD (<10 −8 A/cm 2 ) leakage currents can further reduce the APS noise. Cascaded system analysis shows that the proposed APS imager with a 75 μm pixel pitch can effectively resolve the Nyquist frequency of 6.67 lp/mm, which can be further improved to ∼10 lp/mm if the pixel pitch is reduced to 50 μm. Moreover, the detector entrance

Evaluation of 320x240 pixel LEC GaAs Schottky barrier X-ray imaging arrays, hybridized to CMOS readout circuit based on charge integration

CERN Document Server

Irsigler, R; Alverbro, J; Borglind, J; Froejdh, C; Helander, P; Manolopoulos, S; O'Shea, V; Smith, K

1999-01-01

320x240 pixels GaAs Schottky barrier detector arrays were fabricated, hybridized to silicon readout circuits, and subsequently evaluated. The detector chip was based on semi-insulating LEC GaAs material. The square shaped pixel detector elements were of the Schottky barrier type and had a pitch of 38 mu m. The GaAs wafers were thinned down prior to the fabrication of the ohmic back contact. After dicing, the chips were indium bump, flip-chip bonded to CMOS readout circuits based on charge integration, and finally evaluated. A bias voltage between 50 and 100 V was sufficient to operate the detector. Results on I-V characteristics, noise behaviour and response to X-ray radiation are presented. Images of various objects and slit patterns were acquired by using a standard dental imaging X-ray source. The work done was a part of the XIMAGE project financed by the European Community (Brite-Euram). (author)

Design and characterization of novel monolithic pixel sensors for the ALICE ITS upgrade

Science.gov (United States)

Cavicchioli, C.; Chalmet, P. L.; Giubilato, P.; Hillemanns, H.; Junique, A.; Kugathasan, T.; Mager, M.; Marin Tobon, C. A.; Martinengo, P.; Mattiazzo, S.; Mugnier, H.; Musa, L.; Pantano, D.; Rousset, J.; Reidt, F.; Riedler, P.; Snoeys, W.; Van Hoorne, J. W.; Yang, P.

2014-11-01

Within the R&D activities for the upgrade of the ALICE Inner Tracking System (ITS), Monolithic Active Pixel Sensors (MAPS) are being developed and studied, due to their lower material budget ( 0.3 %X0 in total for each inner layer) and higher granularity ( 20 μm × 20 μm pixels) with respect to the present pixel detector. This paper presents the design and characterization results of the Explorer0 chip, manufactured in the TowerJazz 180 nm CMOS Imaging Sensor process, based on a wafer with high-resistivity (ρ > 1 kΩ cm) and 18 μm thick epitaxial layer. The chip is organized in two sub-matrices with different pixel pitches (20 μm and 30 μm), each of them containing several pixel designs. The collection electrode size and shape, as well as the distance between the electrode and the surrounding electronics, are varied; the chip also offers the possibility to decouple the charge integration time from the readout time, and to change the sensor bias. The charge collection properties of the different pixel variants implemented in Explorer0 have been studied using a 55Fe X-ray source and 1-5 GeV/c electrons and positrons. The sensor capacitance has been estimated, and the effect of the sensor bias has also been examined in detail. A second version of the Explorer0 chip (called Explorer1) has been submitted for production in March 2013, together with a novel circuit with in-pixel discrimination and a sparsified readout. Results from these submissions are also presented.

Experimental characterization of the 192 channel Clear-PEM frontend ASIC coupled to a multi-pixel APD readout of LYSO:Ce crystals

International Nuclear Information System (INIS)

Albuquerque, Edgar; Bexiga, Vasco; Bugalho, Ricardo; Carrico, Bruno; Ferreira, Claudia S.; Ferreira, Miguel; Godinho, Joaquim; Goncalves, Fernando; Leong, Carlos; Lousa, Pedro; Machado, Pedro; Moura, Rui; Neves, Pedro; Ortigao, Catarina; Piedade, Fernando; Pinheiro, Joao F.; Rego, Joel; Rivetti, Angelo; Rodrigues, Pedro; Silva, Jose C.

2009-01-01

In the framework of the Clear-PEM project for the construction of a high-resolution scanner for breast cancer imaging, a very compact and dense frontend electronics system has been developed for readout of multi-pixel S8550 Hamamatsu APDs. The frontend electronics are instrumented with a mixed-signal Application-Specific Integrated Circuit (ASIC), which incorporates 192 low-noise charge pre-amplifiers, shapers, analog memory cells and digital control blocks. Pulses are continuously stored in memory cells at clock frequency. Channels above a common threshold voltage are readout for digitization by off-chip free-sampling ADCs. The ASIC has a size of 7.3x9.8mm 2 and was implemented in a AMS 0.35μm CMOS technology. In this paper the experimental characterization of the Clear-PEM frontend ASIC, reading out multi-pixel APDs coupled to LYSO:Ce crystal matrices, is presented. The chips were mounted on a custom test board connected to six APD arrays and to the data acquisition system. Six 32-pixel LYSO:Ce crystal matrices coupled on both sides to APD arrays were readout by two test boards. All 384 channels were operational. The chip power consumption is 660 mW (3.4 mW per channel). A very stable behavior of the chip was observed, with an estimated ENC of 1200-1300e - at APD gain 100. The inter-channel noise dispersion and mean baseline variation is less than 8% and 0.5%, respectively. The spread in the gain between different channels is found to be 1.5%. Energy resolution of 16.5% at 511 keV and 12.8% at 662 keV has been measured. Timing measurements between the two APDs that readout the same crystal is extracted and compared with detailed Monte Carlo simulations. At 511 keV the measured single photon time RMS resolution is 1.30 ns, in very good agreement with the expected value of 1.34 ns.

Measurements of Ultra-Fast single photon counting chip with energy window and 75 μm pixel pitch with Si and CdTe detectors

International Nuclear Information System (INIS)

Maj, P.; Grybos, P.; Kasinski, K.; Koziol, A.; Krzyzanowska, A.; Kmon, P.; Szczygiel, R.; Zoladz, M.

2017-01-01

Single photon counting pixel detectors become increasingly popular in various 2-D X-ray imaging techniques and scientific experiments mainly in solid state physics, material science and medicine. This paper presents architecture and measurement results of the UFXC32k chip designed in a CMOS 130 nm process. The chip consists of about 50 million transistors and has an area of 9.64 mm × 20.15 mm. The core of the IC is a matrix of 128 × 256 pixels of 75 μm pitch. Each pixel contains a CSA, a shaper with tunable gain, two discriminators with correction circuits and two 14-bit ripple counters operating in a normal mode (with energy window), a long counter mode (one 28-bit counter) and a zero-dead time mode. Gain and noise performance were verified with X-ray radiation and with the chip connected to Si (320 μm thick) and CdTe (750 μ m thick) sensors.

1024-Pixel CMOS Multimodality Joint Cellular Sensor/Stimulator Array for Real-Time Holistic Cellular Characterization and Cell-Based Drug Screening.

Science.gov (United States)

Park, Jong Seok; Aziz, Moez Karim; Li, Sensen; Chi, Taiyun; Grijalva, Sandra Ivonne; Sung, Jung Hoon; Cho, Hee Cheol; Wang, Hua

2018-02-01

This paper presents a fully integrated CMOS multimodality joint sensor/stimulator array with 1024 pixels for real-time holistic cellular characterization and drug screening. The proposed system consists of four pixel groups and four parallel signal-conditioning blocks. Every pixel group contains 16 × 16 pixels, and each pixel includes one gold-plated electrode, four photodiodes, and in-pixel circuits, within a pixel footprint. Each pixel supports real-time extracellular potential recording, optical detection, charge-balanced biphasic current stimulation, and cellular impedance measurement for the same cellular sample. The proposed system is fabricated in a standard 130-nm CMOS process. Rat cardiomyocytes are successfully cultured on-chip. Measured high-resolution optical opacity images, extracellular potential recordings, biphasic current stimulations, and cellular impedance images demonstrate the unique advantages of the system for holistic cell characterization and drug screening. Furthermore, this paper demonstrates the use of optical detection on the on-chip cultured cardiomyocytes to real-time track their cyclic beating pattern and beating rate.

Pixels, Blocks of Pixels, and Polygons: Choosing a Spatial Unit for Thematic Accuracy Assessment

Science.gov (United States)

Pixels, polygons, and blocks of pixels are all potentially viable spatial assessment units for conducting an accuracy assessment. We develop a statistical population-based framework to examine how the spatial unit chosen affects the outcome of an accuracy assessment. The populati...

Monolithic array of 32 SPAD pixels for single-photon imaging at high frame rates

International Nuclear Information System (INIS)

Tisa, Simone; Guerrieri, Fabrizio; Zappa, Franco

2009-01-01

We present a single-chip monolithic array of 32 Single-Photon Avalanche Diodes (SPAD) and associated electronics for imaging at high frame rates and high sensitivity. Photodetectors, front-end circuitry and control electronics used to manage the array are monolithically integrated on the same chip in a standard 0.35 μm CMOS high-voltage technology. The array is composed of 32 'smart' pixels working in photon counting mode and functioning in a parallel fashion. Every cell comprises of an integrated SPAD photodetector, a novel quenching circuit named as Variable Load Quenching Circuit (VLQC), counting electronics and a buffer memory. Proper ancillary electronics that perform the arbitration of photon counts between two consecutive frames is integrated as well. Thanks to the presence of in-pixel memory registers, the inter-frame dead time between subsequent frames is limited to few nanoseconds. Since integration and download are performed simultaneously and the array can be addressed like a standard digital memory, the achievable maximum frame rate is very high in the order of hundreds of thousands of frame/s.

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.

Advanced pixel architectures for scientific image sensors

CERN Document Server

Coath, R; Godbeer, A; Wilson, M; Turchetta, R

2009-01-01

We present recent developments from two projects targeting advanced pixel architectures for scientific applications. Results are reported from FORTIS, a sensor demonstrating variants on a 4T pixel architecture. The variants include differences in pixel and diode size, the in-pixel source follower transistor size and the capacitance of the readout node to optimise for low noise and sensitivity to small amounts of charge. Results are also reported from TPAC, a complex pixel architecture with ~160 transistors per pixel. Both sensors were manufactured in the 0.18μm INMAPS process, which includes a special deep p-well layer and fabrication on a high resistivity epitaxial layer for improved charge collection efficiency.

Gossip: Gaseous pixels

Science.gov (United States)

Koffeman, E. N.

2007-12-01

Several years ago a revolutionary miniature TPC was developed using a pixel chip with a Micromegas foil spanned over it. To overcome the mechanical stability problems and improve the positioning accuracy while spanning a foil on top of a small readout chip a process has been developed in which a Micromegas-like grid is applied on a CMOS wafer in a post-processing step. This aluminum grid is supported on insulating pillars that are created by etching after the grid has been made. The energy resolution (measured on the absorption of the X-rays from a 55Fe source) was remarkably good. Several geometries have since been tested and we now believe that a Gas On Slimmed Silicon Pixel chip' (Gossip) may be realized. The drift region of such a gaseous pixel detector would be reduced to a millimeter. Such a detector is potentially very radiation hard (SLHC vertexing) but aging and sparking must be eliminated.

Gossip: Gaseous pixels

Energy Technology Data Exchange (ETDEWEB)

Koffeman, E.N. [Nikhef, Kruislaan 409, 1098 SJ Amsterdam (Netherlands)], E-mail: d77@nikhef.nl

2007-12-01

Several years ago a revolutionary miniature TPC was developed using a pixel chip with a Micromegas foil spanned over it. To overcome the mechanical stability problems and improve the positioning accuracy while spanning a foil on top of a small readout chip a process has been developed in which a Micromegas-like grid is applied on a CMOS wafer in a post-processing step. This aluminum grid is supported on insulating pillars that are created by etching after the grid has been made. The energy resolution (measured on the absorption of the X-rays from a {sup 55}Fe source) was remarkably good. Several geometries have since been tested and we now believe that a Gas On Slimmed Silicon Pixel chip' (Gossip) may be realized. The drift region of such a gaseous pixel detector would be reduced to a millimeter. Such a detector is potentially very radiation hard (SLHC vertexing) but aging and sparking must be eliminated.

Gossip: Gaseous pixels

International Nuclear Information System (INIS)

Koffeman, E.N.

2007-01-01

Several years ago a revolutionary miniature TPC was developed using a pixel chip with a Micromegas foil spanned over it. To overcome the mechanical stability problems and improve the positioning accuracy while spanning a foil on top of a small readout chip a process has been developed in which a Micromegas-like grid is applied on a CMOS wafer in a post-processing step. This aluminum grid is supported on insulating pillars that are created by etching after the grid has been made. The energy resolution (measured on the absorption of the X-rays from a 55 Fe source) was remarkably good. Several geometries have since been tested and we now believe that a Gas On Slimmed Silicon Pixel chip' (Gossip) may be realized. The drift region of such a gaseous pixel detector would be reduced to a millimeter. Such a detector is potentially very radiation hard (SLHC vertexing) but aging and sparking must be eliminated

Geant4-based simulations of charge collection in CMOS Active Pixel Sensors

International Nuclear Information System (INIS)

Esposito, M.; Allinson, N.M.; Price, T.; Anaxagoras, T.

2017-01-01

Geant4 is an object-oriented toolkit for the simulation of the interaction of particles and radiation with matter. It provides a snapshot of the state of a simulated particle in time, as it travels through a specified geometry. One important area of application is the modelling of radiation detector systems. Here, we extend the abilities of such modelling to include charge transport and sharing in pixelated CMOS Active Pixel Sensors (APSs); though similar effects occur in other pixel detectors. The CMOS APSs discussed were developed in the framework of the PRaVDA consortium to assist the design of custom sensors to be used in an energy-range detector for proton Computed Tomography (pCT). The development of ad-hoc classes, providing a charge transport model for a CMOS APS and its integration into the standard Geant4 toolkit, is described. The proposed charge transport model includes, charge generation, diffusion, collection, and sharing across adjacent pixels, as well as the full electronic chain for a CMOS APS. The proposed model is validated against experimental data acquired with protons in an energy range relevant for pCT.

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.)

New generation of monolithic active pixel sensors for charged particle detection; Developpement d'un capteur de nouvelle generation et son electronique integree pour les collisionneurs futurs

Energy Technology Data Exchange (ETDEWEB)

Deptuch, G

2002-09-01

Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a {sup 55}Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 {mu}m and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 10{sup 12} n/cm{sup 2} and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

A monolithic pixel sensor (TRAPPISTe-2) for particle physics instrumentation in OKI 0.2μm SOI technology

Science.gov (United States)

Soung Yee, L.; Alvarez, P.; Martin, E.; Cortina, E.; Ferrer, C.

2012-12-01

A monolithic active pixel sensor for charged particle tracking has been developed within the frame of a research and development project called TRAPPISTe (Tracking Particles for Physics Instrumentation in SOI Technology). TRAPPISTe aims to study the feasibility of developing a monolithic pixel sensor with SOI technology. TRAPPISTe-2 is the second prototype in this series and was fabricated with an OKI 0.20μm fully depleted (FD-SOI) CMOS process. This device contains test transistors and amplifiers, as well as two pixel matrices with integrated 3-transistor and amplifier readout electronics. The results presented are based on the first electrical measurements performed on the test structures and laser measurements on the pixel matrices.

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...

Development of the micro pixel chamber based on MEMS technology

Science.gov (United States)

Takemura, T.; Takada, A.; Kishimoto, T.; Komura, S.; Kubo, H.; Matsuoka, Y.; Miuchi, K.; Miyamoto, S.; Mizumoto, T.; Mizumura, Y.; Motomura, T.; Nakamasu, Y.; Nakamura, K.; Oda, M.; Ohta, K.; Parker, J. D.; Sawano, T.; Sonoda, S.; Tanimori, T.; Tomono, D.; Yoshikawa, K.

2018-02-01

Micro pixel chambers (μ-PIC) are gaseous two-dimensional imaging detectors originally manufactured using printed circuit board (PCB) technology. They are used in MeV gamma-ray astronomy, medicalimaging, neutron imaging, the search for dark matter, and dose monitoring. The position resolution of the present μ-PIC is approximately 120 μm (RMS), however some applications require a fine position resolution of less than 100 μm. To this end, we have started to develop a μ-PIC based on micro electro mechanical system (MEMS) technology, which provides better manufacturing accuracy than PCB technology. Our simulation predicted the gains of MEMS μ-PICs to be twice those of PCB μ-PICs at the same anode voltage. We manufactured two MEMS μ-PICs and tested them to study their behavior. In these experiments, we successfully operated the fabricatedMEMS μ-PICs and we achieved a maximum gain of approximately 7×103 and collected their energy spectra under irradiation of X-rays from 55Fe. However, the measured gains of the MEMS μ-PICs were less than half of the values predicted in the simulations. We postulated that the gains of the MEMS μ-PICs are diminished by the effect of the silicon used as a semiconducting substrate.

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

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.

An AMOLED AC-Biased Pixel Design Compensating the Threshold Voltage and I-R Drop

Directory of Open Access Journals (Sweden)

Ching-Lin Fan

2011-01-01

Full Text Available We propose a novel pixel design and an AC bias driving method for active-matrix organic light-emitting diode (AM-OLED displays using low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs. The proposed threshold voltage and I-R drop compensation circuit, which comprised three transistors and one capacitor, have been verified to supply uniform output current by simulation work using the Automatic Integrated Circuit Modeling Simulation Program with Integrated Circuit Emphasis (AIM-SPICE simulator. The simulated results demonstrate excellent properties such as low error rate of OLED anode voltage variation (<0.7% and low voltage drop of VDD power line. The proposed pixel circuit effectively enables threshold-voltage-deviation correction of driving TFT and compensates for the voltage drop of VDD power line using AC bias on OLED cathode.

Firmware development and testing of the ATLAS Pixel Detector / IBL ROD card

CERN Document Server

Gabrielli, Alessandro; The ATLAS collaboration; Balbi, Gabriele; Bindi, Marcello; Chen, Shaw-pin; Falchieri, Davide; Flick, Tobias; Hauck, Scott Alan; Hsu, Shih-Chieh; Kretz, Moritz; Kugel, Andreas; Lama, Luca; Travaglini, Riccardo; Wensing, Marius; ATLAS Pixel Collaboration

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 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 testbench using realistic frontend 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 pat...

Firmware development and testing of the ATLAS Pixel Detector / IBL ROD card

CERN Document Server

Balbi, G; The ATLAS collaboration; Gabrielli, A; Lama, L; Travaglini, R; Backhaus, M; Bindi, M; Chen, S-P; Flick, T; Kretz, M; Kugel, A; Wensing, M

2014-01-01

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 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 IBLROD firmware development was three-fold: keeping as much of the PixelROD 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 IBLDAQ testbench using realistic frontend chip model was created to serve as an initial framework for full offline electronic system simulation. In this document, major firmware achievements concerning the IBLROD data path im...

3D-FBK Pixel sensors: recent beam tests results with irradiated devices

CERN Document Server

Micelli, A; Sandaker, H; Stugu, B; Barbero, M; Hugging, F; Karagounis, M; Kostyukhin, V; Kruger, H; Tsung, J W; Wermes, N; Capua, M; Fazio, S; Mastroberardino, A; Susinno, G; Gallrapp, C; Di Girolamo, B; Dobos, D; La Rosa, A; Pernegger, H; Roe, S; Slavicek, T; Pospisil, S; Jakobs, K; Kohler, M; Parzefall, U; Darbo, G; Gariano, G; Gemme, C; Rovani, A; Ruscino, E; Butter, C; Bates, R; Oshea, V; Parker, S; Cavalli-Sforza, M; Grinstein, S; Korokolov, I; Pradilla, C; Einsweiler, K; Garcia-Sciveres, M; Borri, M; Da Via, C; Freestone, J; Kolya, S; Lai, C H; Nellist, C; Pater, J; Thompson, R; Watts, S J; Hoeferkamp, M; Seidel, S; Bolle, E; Gjersdal, H; Sjobaek, K N; Stapnes, S; Rohne, O; Su, D; Young, C; Hansson, P; Grenier, P; Hasi, J; Kenney, C; Kocian, M; Jackson, P; Silverstein, D; Davetak, H; DeWilde, B; Tsybychev, D; Dalla Betta, G F; Gabos, P; Povoli, M; Cobal, M; Giordani, M P; Selmi, L; Cristofoli, A; Esseni, D; Palestri, P; Fleta, C; Lozano, M; Pellegrini, G; Boscardin, M; Bagolini, A; Piemonte, C; Ronchin, S; Zorzi, N; Hansen, T E; Hansen, T; Kok, A; Lietaer, N; Kalliopuska, J; Oja, A

2011-01-01

The Pixel detector is the innermost part of the ATLAS experiment tracking device at the Large Hadron Collider (LHC), and plays a key role in the reconstruction of the primary and secondary vertices of short-lived particles. To cope with the high level of radiation produced during the collider operation, it is planned to add to the present three layers of silicon pixel sensors which constitute the Pixel Detector, an additional layer (Insertable B-Layer, or IBL) of sensors. 3D silicon sensors are one of the technologies which are under study for the IBL. 3D silicon technology is an innovative combination of very-large-scale integration (VLSI) and Micro-Electro-Mechanical-Systems (MEMS) where electrodes are fabricated inside the silicon bulk instead of being implanted on the wafer surfaces. 3D sensors, with electrodes fully or partially penetrating the silicon substrate, are currently fabricated at different processing facilities in Europe and USA. This paper reports on the 2010 June beam test results for irradi...

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.

Design and characterization of novel monolithic pixel sensors for the ALICE ITS upgrade

International Nuclear Information System (INIS)

Cavicchioli, C.; Chalmet, P.L.; Giubilato, P.; Hillemanns, H.; Junique, A.; Kugathasan, T.; Mager, M.; Marin Tobon, C.A.; Martinengo, P.; Mattiazzo, S.; Mugnier, H.; Musa, L.; Pantano, D.; Rousset, J.; Reidt, F.; Riedler, P.; Snoeys, W.; Van Hoorne, J.W.; Yang, P.

2014-01-01

Within the R and D activities for the upgrade of the ALICE Inner Tracking System (ITS), Monolithic Active Pixel Sensors (MAPS) are being developed and studied, due to their lower material budget (∼0.3%X 0 in total for each inner layer) and higher granularity (∼20μm×20μm pixels) with respect to the present pixel detector. This paper presents the design and characterization results of the Explorer0 chip, manufactured in the TowerJazz 180 nm CMOS Imaging Sensor process, based on a wafer with high-resistivity (ρ>1kΩcm) and 18 μm thick epitaxial layer. The chip is organized in two sub-matrices with different pixel pitches (20 μm and 30 μm), each of them containing several pixel designs. The collection electrode size and shape, as well as the distance between the electrode and the surrounding electronics, are varied; the chip also offers the possibility to decouple the charge integration time from the readout time, and to change the sensor bias. The charge collection properties of the different pixel variants implemented in Explorer0 have been studied using a 55 Fe X-ray source and 1–5 GeV/c electrons and positrons. The sensor capacitance has been estimated, and the effect of the sensor bias has also been examined in detail. A second version of the Explorer0 chip (called Explorer1) has been submitted for production in March 2013, together with a novel circuit with in-pixel discrimination and a sparsified readout. Results from these submissions are also presented

Design and characterization of novel monolithic pixel sensors for the ALICE ITS upgrade

Energy Technology Data Exchange (ETDEWEB)

Cavicchioli, C., E-mail: costanza.cavicchioli@cern.ch [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Chalmet, P.L. [MIND, Archamps Technopole, Saint-Julien-en-Genevois, Cedex 74166 (France); Giubilato, P. [Università and INFN, Padova (Italy); Hillemanns, H.; Junique, A.; Kugathasan, T.; Mager, M. [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Marin Tobon, C.A. [Valencia Polytechnic University, Valencia (Spain); Martinengo, P. [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Mattiazzo, S. [Università and INFN, Padova (Italy); Mugnier, H. [MIND, Archamps Technopole, Saint-Julien-en-Genevois, Cedex 74166 (France); Musa, L. [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Pantano, D. [Università and INFN, Padova (Italy); Rousset, J. [MIND, Archamps Technopole, Saint-Julien-en-Genevois, Cedex 74166 (France); Reidt, F. [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Physikalisches Institut, Ruprecht-Karls-Universitaet Heidelberg, Heidelberg (Germany); Riedler, P.; Snoeys, W. [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Van Hoorne, J.W. [CERN European Organization for Nuclear Research, CH-1211 Genève 23 (Switzerland); Technische Universitaet Wien, Vienna (Austria); Yang, P. [Central China Normal University CCNU, Wuhan (China)

2014-11-21

Within the R and D activities for the upgrade of the ALICE Inner Tracking System (ITS), Monolithic Active Pixel Sensors (MAPS) are being developed and studied, due to their lower material budget (∼0.3%X{sub 0} in total for each inner layer) and higher granularity (∼20μm×20μm pixels) with respect to the present pixel detector. This paper presents the design and characterization results of the Explorer0 chip, manufactured in the TowerJazz 180 nm CMOS Imaging Sensor process, based on a wafer with high-resistivity (ρ>1kΩcm) and 18 μm thick epitaxial layer. The chip is organized in two sub-matrices with different pixel pitches (20 μm and 30 μm), each of them containing several pixel designs. The collection electrode size and shape, as well as the distance between the electrode and the surrounding electronics, are varied; the chip also offers the possibility to decouple the charge integration time from the readout time, and to change the sensor bias. The charge collection properties of the different pixel variants implemented in Explorer0 have been studied using a {sup 55}Fe X-ray source and 1–5 GeV/c electrons and positrons. The sensor capacitance has been estimated, and the effect of the sensor bias has also been examined in detail. A second version of the Explorer0 chip (called Explorer1) has been submitted for production in March 2013, together with a novel circuit with in-pixel discrimination and a sparsified readout. Results from these submissions are also presented.

CMS has a heart of pixels

CERN Multimedia

2003-01-01

In the immediate vicinity of the collision point, CMS will be equipped with pixel detectors consisting of no fewer than 50 million pixels measuring 150 microns along each side. Each of the pixels, which receive the signal, is connected to its own electronic circuit by a tiny sphere (seen here in the electron microscope image) measuring 15 to 20 microns in diameter.

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.)

Development of active edge pixel sensors and four-side buttable modules using vertical integration technologies

CERN Document Server

INSPIRE-00219560; Moser, H.-G.; Nisius, R.; Richter, R.H.; Terzo, S.; Weigell, P.

2014-01-01

We present an R&D activity focused on the development of novel modules for the upgrade of the ATLAS pixel system at the High Luminosity LHC (HL-LHC). The modules consist of n-in-p pixel sensors, 100 or 200 $\\mu$m thick, produced at VTT (Finland) with an active edge technology, which considerably reduces the dead area at the periphery of the device. The sensors are interconnected with solder bump-bonding to the ATLAS FE-I3 and FE-I4 read-out chips, and characterized with radioactive sources and beam tests at the CERN-SPS and DESY. The results of these measurements will be discussed for devices before and after irradiation up to a fluence of $5\\times 10^{15}$ \

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.

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.

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

Development of thin pixel sensors and a novel interconnection technology for the SLHC

International Nuclear Information System (INIS)

Macchiolo, A.; Andricek, L.; Beimforde, M.; Dubbert, J.; Ghodbane, N.; Kortner, O.; Kroha, H.; Moser, H.G.; Nisius, R.; Richter, R.H.

2008-01-01

We present an R and D activity aiming to develop a new detector concept in the framework of the ATLAS pixel detector upgrade in view of the Super-LHC. The new devices combine 75-150 μm thick pixels sensors with a vertical integration technology. A new production of thin pixel sensors on n- and p-type material is under way at the MPI Semiconductor Laboratory. These devices will be connected to the ATLAS read-out electronics with the new Solid-Liquid InterDiffusion technique as an alternative to the bump-bonding process. We also plan for the signals to be extracted from the back of the electronics wafer through Inter-Chip-Vias. The compatibility of the Solid-Liquid InterDiffusion process with the silicon sensor functionality has already been demonstrated by measurements on two wafers hosting diodes with an active thickness of 50 μm

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.

Urban Image Classification: Per-Pixel Classifiers, Sub-Pixel Analysis, Object-Based Image Analysis, and Geospatial Methods. 10; Chapter

Science.gov (United States)

Myint, Soe W.; Mesev, Victor; Quattrochi, Dale; Wentz, Elizabeth A.

2013-01-01

Remote sensing methods used to generate base maps to analyze the urban environment rely predominantly on digital sensor data from space-borne platforms. This is due in part from new sources of high spatial resolution data covering the globe, a variety of multispectral and multitemporal sources, sophisticated statistical and geospatial methods, and compatibility with GIS data sources and methods. The goal of this chapter is to review the four groups of classification methods for digital sensor data from space-borne platforms; per-pixel, sub-pixel, object-based (spatial-based), and geospatial methods. Per-pixel methods are widely used methods that classify pixels into distinct categories based solely on the spectral and ancillary information within that pixel. They are used for simple calculations of environmental indices (e.g., NDVI) to sophisticated expert systems to assign urban land covers. Researchers recognize however, that even with the smallest pixel size the spectral information within a pixel is really a combination of multiple urban surfaces. Sub-pixel classification methods therefore aim to statistically quantify the mixture of surfaces to improve overall classification accuracy. While within pixel variations exist, there is also significant evidence that groups of nearby pixels have similar spectral information and therefore belong to the same classification category. Object-oriented methods have emerged that group pixels prior to classification based on spectral similarity and spatial proximity. Classification accuracy using object-based methods show significant success and promise for numerous urban 3 applications. Like the object-oriented methods that recognize the importance of spatial proximity, geospatial methods for urban mapping also utilize neighboring pixels in the classification process. The primary difference though is that geostatistical methods (e.g., spatial autocorrelation methods) are utilized during both the pre- and post

Characterisation of the ATLAS ITK strips front-end chip and development of EUDAQ 2.0 for the EUDET-style pixel telescopes

Energy Technology Data Exchange (ETDEWEB)

Peschke, Richard

2017-03-15

As part of the ATLAS phase-II upgrade a new, all-silicon tracker will be built. The new tracker will consist of silicon pixel sensors and silicon microstrip sensors. For the readout of the microstrip sensor a new readout chip was designed; the so called ATLAS Binary Converter 130 (ABC130) which is based on a 130 nm CMOS technology. The chip consists of an analog Front End built up of 256 channels, each with a preamplifier and a discriminator for converting the analog sensor readout into a binary response. The preamplifier of the ABC130 was designed to have a gain of 90-95 (mV)/(fC). First laboratory measurements with the built-in control circuits have shown a gain of <75 (mV)/(fC). In the course of this thesis a test beam campaign was undertaken to measure the gain in an unbiased system under realistic conditions. The obtained gain varied from ∼90 (mV)/(fC) to ∼100 (mV)/(fC). With this, the values obtained by the test beam campaign are within the specifications. In order to perform the test beam campaign with optimal efficiency, a complete overhaul of the data acquisition framework used for the EUDET type test beam telescopes was necessary. The new version is called EUDAQ 2.0. It is designed to accommodate devices with different integration times such as LHC-type devices with an integration time of only 25 ns, and devices with long integration times such as the MIMOSA26 with an integration time of 114.5 μs. To accomplish this a new synchronization algorithm has been developed. It gives the user full flexibility on the means of synchronizing their own data stream with the system. Beyond this, EUDAQ 2.0 also allows user specific encoding and decoding of data packets. This enables the user to minimize the data overhead and to shift more computation time to the offline stage. To reduce the network overhead EUDAQ 2.0 allows the user to store data locally. The merging is then postponed to the offline stage.

Characterisation of the ATLAS ITK strips front-end chip and development of EUDAQ 2.0 for the EUDET-style pixel telescopes

International Nuclear Information System (INIS)

Peschke, Richard

2017-03-01

As part of the ATLAS phase-II upgrade a new, all-silicon tracker will be built. The new tracker will consist of silicon pixel sensors and silicon microstrip sensors. For the readout of the microstrip sensor a new readout chip was designed; the so called ATLAS Binary Converter 130 (ABC130) which is based on a 130 nm CMOS technology. The chip consists of an analog Front End built up of 256 channels, each with a preamplifier and a discriminator for converting the analog sensor readout into a binary response. The preamplifier of the ABC130 was designed to have a gain of 90-95 (mV)/(fC). First laboratory measurements with the built-in control circuits have shown a gain of <75 (mV)/(fC). In the course of this thesis a test beam campaign was undertaken to measure the gain in an unbiased system under realistic conditions. The obtained gain varied from ∼90 (mV)/(fC) to ∼100 (mV)/(fC). With this, the values obtained by the test beam campaign are within the specifications. In order to perform the test beam campaign with optimal efficiency, a complete overhaul of the data acquisition framework used for the EUDET type test beam telescopes was necessary. The new version is called EUDAQ 2.0. It is designed to accommodate devices with different integration times such as LHC-type devices with an integration time of only 25 ns, and devices with long integration times such as the MIMOSA26 with an integration time of 114.5 μs. To accomplish this a new synchronization algorithm has been developed. It gives the user full flexibility on the means of synchronizing their own data stream with the system. Beyond this, EUDAQ 2.0 also allows user specific encoding and decoding of data packets. This enables the user to minimize the data overhead and to shift more computation time to the offline stage. To reduce the network overhead EUDAQ 2.0 allows the user to store data locally. The merging is then postponed to the offline stage.

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).

Mapping Electrical Crosstalk in Pixelated Sensor Arrays

Science.gov (United States)

Seshadri, Suresh (Inventor); Cole, David (Inventor); Smith, Roger M. (Inventor); Hancock, Bruce R. (Inventor)

2017-01-01

The effects of inter pixel capacitance in a pixilated array may be measured by first resetting all pixels in the array to a first voltage, where a first image is read out, followed by resetting only a subset of pixels in the array to a second voltage, where a second image is read out, where the difference in the first and second images provide information about the inter pixel capacitance. Other embodiments are described and claimed.

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.

Audiovisual integration in depth: multisensory binding and gain as a function of distance.

Science.gov (United States)

Noel, Jean-Paul; Modi, Kahan; Wallace, Mark T; Van der Stoep, Nathan

2018-07-01

The integration of information across sensory modalities is dependent on the spatiotemporal characteristics of the stimuli that are paired. Despite large variation in the distance over which events occur in our environment, relatively little is known regarding how stimulus-observer distance affects multisensory integration. Prior work has suggested that exteroceptive stimuli are integrated over larger temporal intervals in near relative to far space, and that larger multisensory facilitations are evident in far relative to near space. Here, we sought to examine the interrelationship between these previously established distance-related features of multisensory processing. Participants performed an audiovisual simultaneity judgment and redundant target task in near and far space, while audiovisual stimuli were presented at a range of temporal delays (i.e., stimulus onset asynchronies). In line with the previous findings, temporal acuity was poorer in near relative to far space. Furthermore, reaction time to asynchronously presented audiovisual targets suggested a temporal window for fast detection-a range of stimuli asynchronies that was also larger in near as compared to far space. However, the range of reaction times over which multisensory response enhancement was observed was limited to a restricted range of relatively small (i.e., 150 ms) asynchronies, and did not differ significantly between near and far space. Furthermore, for synchronous presentations, these distance-related (i.e., near vs. far) modulations in temporal acuity and multisensory gain correlated negatively at an individual subject level. Thus, the findings support the conclusion that multisensory temporal binding and gain are asymmetrically modulated as a function of distance from the observer, and specifies that this relationship is specific for temporally synchronous audiovisual stimulus presentations.

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

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.

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.

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

A Prototype of a New Generation Readout ASIC in 65 nm CMOS for Pixel Detectors at HL-LHC

CERN Document Server

Pacher, L.; Paternò, A; Panati, S; Demaria, L; Rivetti, A; Da Rocha Rolo, M; Dellacasa, G; Mazza, G; Rotondo, F; Wheadon, R; Loddo, F; Licciulli, F; Ciciriello, F; Marzocca, C; Gaioni, L; Traversi, G; Re, V; De Canio, F; Ratti, L; Marconi, S; Placidi, P; Magazzù, G; Stabile, A; Mattiazzo, S

2018-01-01

The prototype is composed of a matrix of 64×64 pixels with 50 μm × 50 μm cells featuring a compact design, low-noise and low-power performance. The pixel array integrates two diffe- rent analogue front-end architectures working in parallel, one with asynchronous and one with synchronous hit discriminators. Common characteristics are a compact layout able to fit int...

Performance of thin pixel sensors irradiated up to a fluence of 10{sup 16}n{sub eq}cm{sup -2} and development of a new interconnection technology for the upgrade of the ATLAS pixel system

Energy Technology Data Exchange (ETDEWEB)

Macchiolo, A., E-mail: Anna.Macchiolo@mpp.mpg.de [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany); Andricek, L. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany); Max-Planck-Institut Halbleiterlabor, Otto Hahn Ring 6, D-81739 Muenchen (Germany); Beimforde, M. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany); Moser, H.-G. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany); Max-Planck-Institut Halbleiterlabor, Otto Hahn Ring 6, D-81739 Muenchen (Germany); Nisius, R. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany); Richter, R.H. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany); Max-Planck-Institut Halbleiterlabor, Otto Hahn Ring 6, D-81739 Muenchen (Germany); Weigell, P. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805 Muenchen (Germany)

2011-09-11

A new pixel module concept is presented, where thin sensors and a novel vertical integration technique are combined. This R and D activity is carried out in view of the ATLAS pixel detector upgrades. A first set of n-in-p pixel sensors with active thicknesses of 75 and 150{mu}m has been produced using a thinning technique developed at the Max-Planck-Institut Halbleiterlabor (HLL). Charge Collection Efficiency measurements have been performed, yielding a higher CCE than expected from the present radiation damage models. The interconnection of thin n-in-p pixels to the FE-I3 ATLAS electronics is under way, exploiting the Solid Liquid Interdiffusion (SLID) technique developed by the Fraunhofer Institut EMFT. In addition, preliminary studies aimed at Inter-Chip-Vias (ICV) etching into the FE-I3 electronics are reported. ICVs will be used to route the signals vertically through the read-out chip, to newly created pads on the backside. This should serve as a proof of principle for future four-side tileable pixel assemblies, avoiding the cantilever presently needed in the chip for the wire bonding.

Nuclear resonant scattering measurements on (57)Fe by multichannel scaling with a 64-pixel silicon avalanche photodiode linear-array detector.

Science.gov (United States)

Kishimoto, S; Mitsui, T; Haruki, R; Yoda, Y; Taniguchi, T; Shimazaki, S; Ikeno, M; Saito, M; Tanaka, M

2014-11-01

We developed a silicon avalanche photodiode (Si-APD) linear-array detector for use in nuclear resonant scattering experiments using synchrotron X-rays. The Si-APD linear array consists of 64 pixels (pixel size: 100 × 200 μm(2)) with a pixel pitch of 150 μm and depletion depth of 10 μm. An ultrafast frontend circuit allows the X-ray detector to obtain a high output rate of >10(7) cps per pixel. High-performance integrated circuits achieve multichannel scaling over 1024 continuous time bins with a 1 ns resolution for each pixel without dead time. The multichannel scaling method enabled us to record a time spectrum of the 14.4 keV nuclear radiation at each pixel with a time resolution of 1.4 ns (FWHM). This method was successfully applied to nuclear forward scattering and nuclear small-angle scattering on (57)Fe.

Multi-Pixel Photon Counters for Optofluidic Characterization of Particles and Microalgae

Directory of Open Access Journals (Sweden)

Pouya Asrar

2015-06-01

Full Text Available We have developed an optofluidic biosensor to study microscale particles and different species of microalgae. The system is comprised of a microchannel with a set of chevron-shaped grooves. The chevrons allows for hydrodynamic focusing of the core stream in the center using a sheath fluid. The device is equipped with a new generation of highly sensitive photodetectors, multi-pixel photon counter (MPPC, with high gain values and an extremely small footprint. Two different sizes of high intensity fluorescent microspheres and three different species of algae (Chlamydomonas reinhardtii strain 21 gr, Chlamydomonas suppressor, and Chlorella sorokiniana were studied. The forward scattering emissions generated by samples passing through the interrogation region were carried through a multimode fiber, located in 135 degree with respect to the excitation fiber, and detected by a MPPC. The signal outputs obtained from each sample were collected using a data acquisition system and utilized for further statistical analysis. Larger particles or cells demonstrated larger peak height and width, and consequently larger peak area. The average signal output (integral of the peak for Chlamydomonas reinhardtii strain 21 gr, Chlamydomonas suppressor, and Chlorella sorokiniana falls between the values found for the 3.2 and 10.2 μm beads. Different types of algae were also successfully characterized.

Fast Imaging Detector Readout Circuits with In-Pixel ADCs for Fourier Transform Imaging Spectrometers

Science.gov (United States)

Rider, D.; Blavier, J-F.; Cunningham, T.; Hancock, B.; Key, R.; Pannell, Z.; Sander, S.; Seshadri, S.; Sun, C.; Wrigley, C.

2011-01-01

Focal plane arrays (FPAs) with high frame rates and many pixels benefit several upcoming Earth science missions including GEO-CAPE, GACM, and ACE by enabling broader spatial coverage and higher spectral resolution. FPAs for the PanFTS, a high spatial resolution Fourier transform spectrometer and a candidate instrument for the GEO-CAPE mission are the focus of the developments reported here, but this FPA technology has the potential to enable a variety of future measurements and instruments. The ESTO ACT Program funded the developed of a fast readout integrated circuit (ROIC) based on an innovative in-pixel analog-to-digital converter (ADC). The 128 X 128 pixel ROIC features 60 ?m pixels, a 14-bit ADC in each pixel and operates at a continuous frame rate of 14 kHz consuming only 1.1 W of power. The ROIC outputs digitized data completely eliminating the bulky, power consuming signal chains needed by conventional FPAs. The 128 X 128 pixel ROIC has been fabricated in CMOS and tested at the Jet Propulsion Laboratory. The current version is designed to be hybridized with PIN photodiode arrays via indium bump bonding for light detection in the visible and ultraviolet spectral regions. However, the ROIC design incorporates a small photodiode in each cell to permit detailed characterization of the ROICperformance without the need for hybridization. We will describe the essential features of the ROIC design and present results of ROIC performance measurements.

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.

Poster - 01: LabPET II Pixelated APD-Based PET Scanner for High-Resolution Preclinical Imaging

Energy Technology Data Exchange (ETDEWEB)

Lecomte, Roger; Arpin, Louis; Beaudoin, Jean-François; Bergeron, Mélanie; Bouchard, Jonathan; Bouziri, Haithem; Cadorette, Jules; Gaudin, Émilie; Jürgensen, Nadia; Koua, Konin Calliste; Trépanier, Pierre-Yves Lauzier; Leroux, Jean-Daniel; Loignon-Houle, Francis; Njejimana, Larissa; Paillé, Maxime; Paulin, Caroline; Pepin, Catherine; Pratte, Jean-François; Samson, Arnaud; Thibaudeau, Christian [Université de Sherbrooke, Université de Sherbrooke, CIMS/CRCHUS, Université de Sherbrooke, Université de Sherbrooke, Université de Sherbrooke, CIMS/CRCHUS, Université de Sherbrooke, Université de Sherbrooke, 3IT, Université de Sherbrooke, Novalgo Inc., Université de Sherbrooke, Université de Sherbrooke, CIMS/CRCHUS, 3IT, Université de Sherbrooke, Université de Sherbrooke, Université de Sherbrooke, Université de Sherbrooke, 3IT, Université de Sherbrooke (Canada); and others

2016-08-15

Purpose: LabPET II is a new generation APD-based PET scanner designed to achieve sub-mm spatial resolution using truly pixelated detectors and highly integrated parallel front-end processing electronics. Methods: The basic element uses a 4×8 array of 1.12×1.12 mm{sup 2} Lu{sub 1.9}Y{sub 0.1}SiO{sub 5}:Ce (LYSO) scintillator pixels with one-to-one coupling to a 4×8 pixelated monolithic APD array mounted on a ceramic carrier. Four detector arrays are mounted on a daughter board carrying two flip-chip, 64-channel, mixed-signal, application-specific integrated circuits (ASIC) on the backside interfacing to two detector arrays each. Fully parallel signal processing was implemented in silico by encoding time and energy information using a dual-threshold Time-over-Threshold (ToT) scheme. The self-contained 128-channel detector module was designed as a generic component for ultra-high resolution PET imaging of small to medium-size animals. Results: Energy and timing performance were optimized by carefully setting ToT thresholds to minimize the noise/slope ratio. ToT spectra clearly show resolved 511 keV photopeak and Compton edge with ToT resolution well below 10%. After correction for nonlinear ToT response, energy resolution is typically 24±2% FWHM. Coincidence time resolution between opposing 128-channel modules is below 4 ns FWHM. Initial imaging results demonstrate that 0.8 mm hot spots of a Derenzo phantom can be resolved. Conclusion: A new generation PET scanner featuring truly pixelated detectors was developed and shown to achieve a spatial resolution approaching the physical limit of PET. Future plans are to integrate a small-bore dedicated mouse version of the scanner within a PET/CT platform.

Air pollution policies in Europe: efficiency gains from integrating climate effects with damage costs to health and crops

International Nuclear Information System (INIS)

Tollefsen, Petter; Rypdal, Kristin; Torvanger, Asbjorn; Rive, Nathan

2009-01-01

Emissions of air pollutants cause damage to health and crops, but several air pollutants also have an effect on climate through radiative forcing. We investigate efficiency gains achieved by integrating climate impacts of air pollutants into air quality strategies for the EU region. The pollutants included in this study are SO 2 , NH 3 , VOC, CO, NO x , black carbon, organic carbon, PM 2.5 , and CH 4 . We illustrate the relative importance of climate change effects compared to damage to health and crops, as well as monetary gains of including climate change contributions. The analysis considers marginal abatement costs and compares air quality and climate damage in Euros. We optimize abatement policies with respect to both climate and health impacts, which imply implementing all measures that yield a net benefit. The efficiency gains of the integrated policy are in the order of 2.5 billion Euros, compared to optimal abatement based on health and crop damage only, justifying increased abatement efforts of close to 50%. Climate effect of methane is the single most important factor. If climate change is considered on a 20- instead of a 100-year time-scale, the efficiency gain almost doubles. Our results indicate that air pollution policies should be supplemented with climate damage considerations.

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.

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.

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.

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

Development of active edge pixel sensors and four-side buttable modules using vertical integration technologies

Energy Technology Data Exchange (ETDEWEB)

Macchiolo, A., E-mail: Anna.Macchiolo@mpp.mpg.de [Max-Planck-Institut for Physics, Föhringer Ring 6, D-80805 Munich (Germany); Andricek, L. [Semiconductor Laboratory of the Max-Planck-Society, Otto Hahn Ring 6, D-81739 Munich (Germany); Moser, H.-G.; Nisius, R. [Max-Planck-Institut for Physics, Föhringer Ring 6, D-80805 Munich (Germany); Richter, R.H. [Semiconductor Laboratory of the Max-Planck-Society, Otto Hahn Ring 6, D-81739 Munich (Germany); Terzo, S.; Weigell, P. [Max-Planck-Institut for Physics, Föhringer Ring 6, D-80805 Munich (Germany)

2014-11-21

We present an R and D activity focused on the development of novel modules for the upgrade of the ATLAS pixel system at the High Luminosity LHC (HL-LHC). The modules consist of n-in-p pixel sensors, 100 or 200 μm thick, produced at VTT (Finland) with an active edge technology, which considerably reduces the dead area at the periphery of the device. The sensors are interconnected with solder bump-bonding to the ATLAS FE-I3 and FE-I4 read-out chips, and characterised with radioactive sources and beam tests at the CERN-SPS and DESY. The results of these measurements will be discussed for devices before and after irradiation up to a fluence of 5×10{sub 15}n{sub eq}/cm{sup 2}. We will also report on the R and D activity to obtain Inter Chip Vias (ICVs) on the ATLAS read-out chip in collaboration with the Fraunhofer Institute EMFT. This step is meant to prove the feasibility of the signal transport to the newly created readout pads on the backside of the chips allowing for four side buttable devices without the presently used cantilever for wire bonding. The read-out chips with ICVs will be interconnected to thin pixel sensors, 75 μm and 150 μm thick, with the Solid Liquid Interdiffusion (SLID) technology, which is an alternative to the standard solder bump-bonding.

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.

Gesundes Kinzigtal Integrated Care: improving population health by a shared health gain approach and a shared savings contract

Directory of Open Access Journals (Sweden)

H. Hildebrandt

2010-06-01

Full Text Available Introduction: Integrated care solutions need supportive financial incentives. In this paper we describe the financial architecture and operative details of the integrated pilot Gesundes Kinzigtal.Description of integrated care case: Located in Southwest Germany, Gesundes Kinzigtal is one of the few population-based integrated care approaches in Germany, organising care across all health service sectors and indications. The system serving around half of the population of the region is run by a regional health management company (Gesundes Kinzigtal GmbH in coope­ration with the physicians' network in the region (MQNK, a German health care management company with a background in medical sociology and health economics (OptiMedis AG and with two statutory health insurers (among them is the biggest health insurer in Southwest Germany: AOK Baden-Württemberg.Discussion and (preliminary conclusion: The shared savings contract between Gesundes Kinzigtal GmbH and the two health insurers, providing financial incentives for managers and health care providers to realize a sub­stantial efficiency gain, could be an appropriate contractual base of Gesundes Kinzigtal's population health gain approach. This approach is based on the assumption that a more effective trans-sector organisation of Germany's health care system and increased investments in well-designed preventive programmes will lead to a reduction in  morbidity, and in particular to a reduced incidence and prevalence of chronic diseases. This, in turn, is to lead to a comparative reduction in health care cost. Although the comparative cost in the Kinzigtal region has been reduced from the onset of Gesundes Kinzigtal Integrated Care, only future research will have to demonstrate whether - and to what extent - cost reduction may be attributed to a real population health gain.

Gesundes Kinzigtal Integrated Care: improving population health by a shared health gain approach and a shared savings contract

Directory of Open Access Journals (Sweden)

H. Hildebrandt

2010-06-01

Full Text Available Introduction: Integrated care solutions need supportive financial incentives. In this paper we describe the financial architecture and operative details of the integrated pilot 'Gesundes Kinzigtal'. Description of integrated care case: Located in Southwest Germany, 'Gesundes Kinzigtal' is one of the few population-based integrated care approaches in Germany, organising care across all health service sectors and indications. The system serving around half of the population of the region is run by a regional health management company (Gesundes Kinzigtal GmbH in coope­ration with the physicians' network in the region (MQNK, a German health care management company with a background in medical sociology and health economics (OptiMedis AG and with two statutory health insurers (among them is the biggest health insurer in Southwest Germany: AOK Baden-Württemberg. Discussion and (preliminary conclusion: The shared savings contract between Gesundes Kinzigtal GmbH and the two health insurers, providing financial incentives for managers and health care providers to realize a sub­stantial efficiency gain, could be an appropriate contractual base of Gesundes Kinzigtal's population health gain approach. This approach is based on the assumption that a more effective trans-sector organisation of Germany's health care system and increased investments in well-designed preventive programmes will lead to a reduction in  morbidity, and in particular to a reduced incidence and prevalence of chronic diseases. This, in turn, is to lead to a comparative reduction in health care cost. Although the comparative cost in the Kinzigtal region has been reduced from the onset of Gesundes Kinzigtal Integrated Care, only future research will have to demonstrate whether - and to what extent - cost reduction may be attributed to a real population health gain.

Calculating Viewing Angles Pixel by Pixel in Optical Remote Sensing Satellite Imagery Using the Rational Function Model

OpenAIRE

Kai Xu; Guo Zhang; Qingjun Zhang; Deren Li

2018-01-01

In studies involving the extraction of surface physical parameters using optical remote sensing satellite imagery, sun-sensor geometry must be known, especially for sensor viewing angles. However, while pixel-by-pixel acquisitions of sensor viewing angles are of critical importance to many studies, currently available algorithms for calculating sensor-viewing angles focus only on the center-point pixel or are complicated and are not well known. Thus, this study aims to provide a simple and ge...

High speed gain coupled DFB laser diode integrated with MQW electroabsorption modulator

International Nuclear Information System (INIS)

Kim, Myung Gyoo; Lee, Seung Won; Park, Seong Su; Oh, Dae Kon; Lee, Hee Tae; Kim, Hong man; Pyun, Kwang Eui

1998-01-01

We have demonstrated stable modulation characteristics of the gain coupled distributed feedback(GC-DFB) laser diode integrated with butt-coupled InGaAsP/InGaAsP strain compensated MQW(multiple-Quantum-well) modulator for high speed optical transmission. For this purpose, we have adopted the InGaAsP/InGaAsP strain compensated MQW structure for the EA modulator and n-doped InGaAs absorptive grating for DFB laser. The typical threshold current and slope efficiency were about 15 mA and 0.1 mW/mA, respectively. The extinction ratio of fabricated integrated device was about 15 dB at -2 V, and the small signal bandwidth was shown to be around 17GHz. We also found that the α parameter becomes negative at below a -0.6 V bias voltage. We transmitted 10 Gbps NRZ electrical signal over 90 km of standard single mode optical fiber (SMF). A clearly opened eye diagram was observed in the modulated output

High speed gain coupled DFB laser diode integrated with MQW electroabsorption modulator

CERN Document Server

Kim, M G; Park, S S; Oh, D K; Lee, H T; Kim, H M; Pyun, K E

1998-01-01

We have demonstrated stable modulation characteristics of the gain coupled distributed feedback(GC-DFB) laser diode integrated with butt-coupled InGaAsP/InGaAsP strain compensated MQW(multiple-Quantum-well) modulator for high speed optical transmission. For this purpose, we have adopted the InGaAsP/InGaAsP strain compensated MQW structure for the EA modulator and n-doped InGaAs absorptive grating for DFB laser. The typical threshold current and slope efficiency were about 15 mA and 0.1 mW/mA, respectively. The extinction ratio of fabricated integrated device was about 15 dB at -2 V, and the small signal bandwidth was shown to be around 17GHz. We also found that the alpha parameter becomes negative at below a -0.6 V bias voltage. We transmitted 10 Gbps NRZ electrical signal over 90 km of standard single mode optical fiber (SMF). A clearly opened eye diagram was observed in the modulated output.

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.

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.

Power and area efficient 4-bit column-level ADC in a CMOS pixel sensor for the ILD vertex detector

International Nuclear Information System (INIS)

Zhang, L; Morel, F; Hu-Guo, Ch; Hu, Y

2013-01-01

A 48 × 64 pixels prototype CMOS pixel sensor (CPS) integrated with 4-bit column-level, self triggered ADCs for the outer layers of the ILD vertex detector (VTX) was developed and fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation. The ADCs accommodating the pixel read out in a rolling shutter mode complete the conversion by performing a multi-bit/step approximation. The design was optimised for power saving at sampling frequency. The prototype sensor is currently at the stage of being started testing and evaluation. So what is described is based on post simulation results rather than test data. This 4-bit ADC dissipates, at a 3-V supply and 6.25-MS/s sampling rate, 486 μW in its inactive mode, which is by far the most frequent. This value rises to 714 μW in case of the active mode. Its footprint amounts to 35 × 545 μm 2 .

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.

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

Low Power Camera-on-a-Chip Using CMOS Active Pixel Sensor Technology

Science.gov (United States)

Fossum, E. R.

1995-01-01

A second generation image sensor technology has been developed at the NASA Jet Propulsion Laboratory as a result of the continuing need to miniaturize space science imaging instruments. Implemented using standard CMOS, the active pixel sensor (APS) technology permits the integration of the detector array with on-chip timing, control and signal chain electronics, including analog-to-digital conversion.

Temporal Gain Correction for X-Ray Calorimeter Spectrometers

Science.gov (United States)

Porter, F. S.; Chiao, M. P.; Eckart, M. E.; Fujimoto, R.; Ishisaki, Y.; Kelley, R. L.; Kilbourne, C. A.; Leutenegger, M. A.; McCammon, D.; Mitsuda, K.

2016-01-01

Calorimetric X-ray detectors are very sensitive to their environment. The boundary conditions can have a profound effect on the gain including heat sink temperature, the local radiation temperature, bias, and the temperature of the readout electronics. Any variation in the boundary conditions can cause temporal variations in the gain of the detector and compromise both the energy scale and the resolving power of the spectrometer. Most production X-ray calorimeter spectrometers, both on the ground and in space, have some means of tracking the gain as a function of time, often using a calibration spectral line. For small gain changes, a linear stretch correction is often sufficient. However, the detectors are intrinsically non-linear and often the event analysis, i.e., shaping, optimal filters etc., add additional non-linearity. Thus for large gain variations or when the best possible precision is required, a linear stretch correction is not sufficient. Here, we discuss a new correction technique based on non-linear interpolation of the energy-scale functions. Using Astro-HSXS calibration data, we demonstrate that the correction can recover the X-ray energy to better than 1 part in 104 over the entire spectral band to above 12 keV even for large-scale gain variations. This method will be used to correct any temporal drift of the on-orbit per-pixel gain using on-board calibration sources for the SXS instrument on the Astro-H observatory.

Time-resolved and position-resolved X-ray spectrometry with a pixelated detector

Energy Technology Data Exchange (ETDEWEB)

Sievers, Peter

2012-12-07

The aim of the work presented here was to measure X-ray spectra with a pixelated detector. Due to effects in the sensor the spectrum cannot be measured directly and has to be calculated by a deconvolution of the measured data. In the scope of this work the deconvolution of the measured spectra could be enhanced considerably by - amongst other things - the introduction of the Bayesian deconvolution method. Those improvements opened the possibilities for further measurements. For the measurements the detectors of the Medipix family have been used. They are nowadays used for a wide range of applications and scientific research. Their main advantage is the very high position resolution gained by a pixel pitch of 55 μm and a high number of 65536 pixels. The Timepix detector has, in particular, two special possibilities of measurement: the ToA mode and the ToT mode. In ToA mode the arrival time of an impinging photon is measured and in ToT mode the amount of deposited charge is measured. The most common method of operation is counting the number of impinging photons that release a charge higher than a preset threshold in each pixel. As this released charge is proportional to the energy deposition of the impinging photon, one can perform energy-sensitive measurements. To perform the deconvolution of the measured energy distribution there is a need of an energy response matrix describing the detector response on radiation. For some detectors it is possible to obtain an analytic model of the response functions. Due to the high discrepancy between the impinging spectrum and the measured spectrum in case of detectors of the Medipix family, there is so far no analytic model. Thus, the detector response has to be simulated. As I could improve the precision of the measurement quite extensively, I also intended to tune the simulation with more accurate and appropriate models to gain the same level of accuracy. The results of measurement and simulation have then been compared and

Time-resolved and position-resolved X-ray spectrometry with a pixelated detector

International Nuclear Information System (INIS)

Sievers, Peter

2012-01-01

The aim of the work presented here was to measure X-ray spectra with a pixelated detector. Due to effects in the sensor the spectrum cannot be measured directly and has to be calculated by a deconvolution of the measured data. In the scope of this work the deconvolution of the measured spectra could be enhanced considerably by - amongst other things - the introduction of the Bayesian deconvolution method. Those improvements opened the possibilities for further measurements. For the measurements the detectors of the Medipix family have been used. They are nowadays used for a wide range of applications and scientific research. Their main advantage is the very high position resolution gained by a pixel pitch of 55 μm and a high number of 65536 pixels. The Timepix detector has, in particular, two special possibilities of measurement: the ToA mode and the ToT mode. In ToA mode the arrival time of an impinging photon is measured and in ToT mode the amount of deposited charge is measured. The most common method of operation is counting the number of impinging photons that release a charge higher than a preset threshold in each pixel. As this released charge is proportional to the energy deposition of the impinging photon, one can perform energy-sensitive measurements. To perform the deconvolution of the measured energy distribution there is a need of an energy response matrix describing the detector response on radiation. For some detectors it is possible to obtain an analytic model of the response functions. Due to the high discrepancy between the impinging spectrum and the measured spectrum in case of detectors of the Medipix family, there is so far no analytic model. Thus, the detector response has to be simulated. As I could improve the precision of the measurement quite extensively, I also intended to tune the simulation with more accurate and appropriate models to gain the same level of accuracy. The results of measurement and simulation have then been compared and

Investigation of Properties of Novel Silicon Pixel Assemblies Employing Thin n-in-p Sensors and 3D-Integration

CERN Document Server

Weigell, Philipp

Until the end of the 2020 decade the LHC programme will be defining the high energy frontier of particle physics. During this time, three upgrade steps of the accelerator are currently planned to further increase the luminosity and energy reach. In the course of these upgrades the specifications of several parts of the current LHC detectors will be exceeded. Especially, the innermost tracking detectors are challenged by the increasing track densities and the radiation damage. This thesis focuses on the implications for the ATLAS experiment. Here, around 2021/2, after having collected an integrated luminosity of around 300/fb¹ , the silicon and gas detector components of the inner tracker will reach the end of their lifetime and will need to be replaced to ensure sufficient performance for continued running|especially if the luminosity is raised to about 5x10^35/(cm²s¹ ) as currently planned. An all silicon inner detector is foreseen to be installed. This upgrade demands cost-effective pixel assemblies with...

Development and simulation results of a sparsification and readout circuit for wide pixel matrices

International Nuclear Information System (INIS)

Gabrielli, A.; Giorgi, F.; Morsani, F.; Villa, M.

2011-01-01

In future collider experiments, the increasing luminosity and centre of mass energy are rising challenging problems in the design of new inner tracking systems. In this context we develop high-efficiency readout architectures for large binary pixel matrices that are meant to cope with the high-stressing conditions foreseen in the innermost layers of a tracker [The SuperB Conceptual Design Report, INFN/AE-07/02, SLAC-R-856, LAL 07-15, Available online at: (http://www.pi.infn.it/SuperB)]. We model and design digital readout circuits to be integrated on VLSI ASICs. These architectures can be realized with different technology processes and sensors: they can be implemented on the same silicon sensor substrate of a CMOS MAPS devices (Monolithic Active Pixel Sensor), on the CMOS tier of a hybrid pixel sensor or in a 3D chip where the digital layer is stacked on the sensor and the analog layers [V. Re et al., Nuc. Instr. and Meth. in Phys. Res. A, (doi:10.1016/j.nima.2010.05.039)]. In the presented work, we consider a data-push architecture designed for a sensor matrix of an area of about 1.3 cm 2 with a pitch of 50 microns. The readout circuit tries to take great advantage of the high density of in-pixel digital logic allowed by vertical integration. We aim at sustaining a rate density of 100 Mtrack . s -1 . cm -2 with a temporal resolution below 1 μs. We show how this architecture can cope with these stressing conditions presenting the results of Monte Carlo simulations.

Development and simulation results of a sparsification and readout circuit for wide pixel matrices

Energy Technology Data Exchange (ETDEWEB)

Gabrielli, A.; Giorgi, F. [University and INFN of Bologna (Italy); Morsani, F. [University and INFN of Pisa (Italy); Villa, M. [University and INFN of Bologna (Italy)

2011-06-15

In future collider experiments, the increasing luminosity and centre of mass energy are rising challenging problems in the design of new inner tracking systems. In this context we develop high-efficiency readout architectures for large binary pixel matrices that are meant to cope with the high-stressing conditions foreseen in the innermost layers of a tracker [The SuperB Conceptual Design Report, INFN/AE-07/02, SLAC-R-856, LAL 07-15, Available online at: (http://www.pi.infn.it/SuperB)]. We model and design digital readout circuits to be integrated on VLSI ASICs. These architectures can be realized with different technology processes and sensors: they can be implemented on the same silicon sensor substrate of a CMOS MAPS devices (Monolithic Active Pixel Sensor), on the CMOS tier of a hybrid pixel sensor or in a 3D chip where the digital layer is stacked on the sensor and the analog layers [V. Re et al., Nuc. Instr. and Meth. in Phys. Res. A, (doi:10.1016/j.nima.2010.05.039)]. In the presented work, we consider a data-push architecture designed for a sensor matrix of an area of about 1.3 cm{sup 2} with a pitch of 50 microns. The readout circuit tries to take great advantage of the high density of in-pixel digital logic allowed by vertical integration. We aim at sustaining a rate density of 100 Mtrack . s{sup -1} . cm{sup -2} with a temporal resolution below 1 {mu}s. We show how this architecture can cope with these stressing conditions presenting the results of Monte Carlo simulations.

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...

A Novel LTPS-TFT Pixel Circuit to Compensate the Electronic Degradation for Active-Matrix Organic Light-Emitting Diode Displays

Directory of Open Access Journals (Sweden)

Ching-Lin Fan

2013-01-01

Full Text Available A novel pixel driving circuit for active-matrix organic light-emitting diode (AMOLED displays with low-temperature polycrystalline-silicon thin-film transistors (LTPS-TFTs is studied. The proposed compensation pixel circuit is driven by voltage programming scheme, which is composed of five TFTs and one capacitor, and has been certified to provide uniform output current by the Automatic Integrated Circuit Modeling Simulation Program with Integrated Circuit Emphasis (AIM-SPICE simulator. The results of simulation show excellent performance, such as the low average error rate of OLED current variation (<0.5% and the low average nonuniformity of OLED current variation (<0.8% while the shift of threshold voltage of the driving poly-Si TFT and the OLED are both in the worst case ( V for TFT and  V for OLED. The proposed pixel circuit shows high immunity to the threshold voltage deviation of both the driving poly-Si TFT and the OLED.

ISPA (imaging silicon pixel array) experiment

CERN Multimedia

Patrice Loïez

2002-01-01

The bump-bonded silicon pixel detector, developed at CERN by the EP-MIC group, is shown here in its ceramic carrier. Both represent the ISPA-tube anode. The chip features between 1024 (called OMEGA-1) and 8196 (ALICE-1) active pixels.

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.

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.

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

Development of N+ in P pixel sensors for a high-luminosity large hadron collider

Science.gov (United States)

Kamada, Shintaro; Yamamura, Kazuhisa; Unno, Yoshinobu; Ikegami, Yoichi

2014-11-01

Hamamatsu Photonics K. K. is developing an N+ in a p planar pixel sensor with high radiation tolerance for the high-luminosity large hadron collider (HL-LHC). The N+ in the p planar pixel sensor is a candidate for the HL-LHC and offers the advantages of high radiation tolerance at a reasonable price compared with the N+ in an n planar sensor, the three-dimensional sensor, and the diamond sensor. However, the N+ in the p planar pixel sensor still presents some problems that need to be solved, such as its slim edge and the danger of sparks between the sensor and readout integrated circuit. We are now attempting to solve these problems with wafer-level processes, which is important for mass production. To date, we have obtained a 250-μm edge with an applied bias voltage of 1000 V. To protect against high-voltage sparks from the edge, we suggest some possible designs for the N+ edge.

E-Beam Effects on CMOS Active Pixel Sensors

International Nuclear Information System (INIS)

Kang, Dong Ook; Jo, Gyu Seong; Kim, Hyeon Daek; Kim, Hyunk Taek; Kim, Jong Yeol; Kim, Chan Kyu

2011-01-01

Three different CMOS active pixel structures manufactured in a deep submicron process have been evaluated with electron beam. The devices were exposed to 1 MeV electron beam up to 5kGy. Dark current increased after E-beam irradiation differently at each pixel structure. Dark current change is dependent on CMOS pixel structures. CMOS image sensors are now good candidates in demanding applications such as medical image sensor, particle detection and space remote sensing. In these situations, CISs are exposed to high doses of radiation. In fact radiation is known to generate trapped charge in CMOS oxides. It can lead to threshold voltage shifts and current leakages in MOSFETs and dark current increase in photodiodes. We studied ionizing effects in three types of CMOS APSs fabricated by 0.25 CMOS process. The devices were irradiated by a Co 60 source up to 50kGy. All irradiation took place at room temperature. The dark current in the three different pixels exhibits increase with electron beam exposure. From the above figure, the change of dark current is dependent on the pixel structure. Double junction structure has shown relatively small increase of dark current after electron beam irradiation. The dark current in the three different pixels exhibits increase with electron beam exposure. The contribution of the total ionizing dose to the dark current increase is small here, since the devices were left unbiased during the electron beam irradiation. Radiation hardness in dependent on the pixel structures. Pixel2 is relatively vulnerable to radiation exposure. Pixel3 has radiation hardened structure

Characterisation of the high dynamic range Large Pixel Detector (LPD) and its use at X-ray free electron laser sources

Science.gov (United States)

Veale, M. C.; Adkin, P.; Booker, P.; Coughlan, J.; French, M. J.; Hart, M.; Nicholls, T.; Schneider, A.; Seller, P.; Pape, I.; Sawhney, K.; Carini, G. A.; Hart, P. A.

2017-12-01

The STFC Rutherford Appleton Laboratory have delivered the Large Pixel Detector (LPD) for MHz frame rate imaging at the European XFEL. The detector system has an active area of 0.5 m × 0.5 m and consists of a million pixels on a 500 μm pitch. Sensors have been produced from 500 μm thick Hammamatsu silicon tiles that have been bump bonded to the readout ASIC using a silver epoxy and gold stud technique. Each pixel of the detector system is capable of measuring 105 12 keV photons per image readout at 4.5 MHz. In this paper results from the testing of these detectors at the Diamond Light Source and the Linac Coherent Light Source (LCLS) are presented. The performance of the detector in terms of linearity, spatial uniformity and the performance of the different ASIC gain stages is characterised.

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...

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...

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...

Building CMS Pixel Barrel Detectur Modules

CERN Document Server

König, S; Horisberger, R.; Meier, B.; Rohe, T.; Streuli, S.; Weber, R.; Kastli, H.Chr.; Erdmann, W.

2007-01-01

For the barrel part of the CMS pixel tracker about 800 silicon pixel detector modules are required. The modules are bump bonded, assembled and tested at the Paul Scherrer Institute. This article describes the experience acquired during the assembly of the first ~200 modules.

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...

PIXEL PATTERN BASED STEGANOGRAPHY ON IMAGES

Directory of Open Access Journals (Sweden)

R. Rejani

2015-02-01

Full Text Available One of the drawback of most of the existing steganography methods is that it alters the bits used for storing color information. Some of the examples include LSB or MSB based steganography. There are also various existing methods like Dynamic RGB Intensity Based Steganography Scheme, Secure RGB Image Steganography from Pixel Indicator to Triple Algorithm etc that can be used to find out the steganography method used and break it. Another drawback of the existing methods is that it adds noise to the image which makes the image look dull or grainy making it suspicious for a person about existence of a hidden message within the image. To overcome these shortcomings we have come up with a pixel pattern based steganography which involved hiding the message within in image by using the existing RGB values whenever possible at pixel level or with minimum changes. Along with the image a key will also be used to decrypt the message stored at pixel levels. For further protection, both the message stored as well as the key file will be in encrypted format which can have same or different keys or decryption. Hence we call it as a RGB pixel pattern based steganography.

Development of a time projection chamber with micro-pixel electrodes

International Nuclear Information System (INIS)

Kubo, Hidetoshi; Miuchi, Kentaro; Nagayoshi, Tsutomu; Ochi, Atsuhiko; Orito, Reiko; Takada, Atsushi; Tanimori, Toru; Ueno, Masaru

2003-01-01

A time projection chamber (TPC) based on a gaseous chamber with micro-pixel electrodes (μ-PIC) has been developed for measuring three-dimensional tracks of charged particles. The μ-PIC with a detection area of 10x10 cm 2 consists of a double-sided printing circuit board. Anode pixels are formed with 0.4 mm pitch on strips aligned perpendicular to the cathode strips in order to obtain a two-dimensional position. In the TPC with drift length of 8 cm, 4 mm wide field cage electrodes are aligned at 1 mm spaces and a uniform electric field of about 0.4 kV/cm is produced. For encoding of the three-dimensional position a synchronous readout system has been developed using Field Programmable Gate Arrays with 40 MHz clock. This system enables us to reconstruct the three-dimensional track of the particle at successive points like a cloud chamber even at high event rate. The drift velocity of electrons in the TPC was measured with the tracks of cosmic muons for 3 days, during which the TPC worked stably with the gas gain of 3000. With a radioisotope of gamma-ray source the three-dimensional track of a Compton scattered electron was taken successfully

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.

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 ...

Search for MH370: New Geologic Insights Gained from Integrating Multiple Geophysical Datasets

Science.gov (United States)

McBee, J.; Gharib, J. J.; Ingle, S.

2017-12-01

During the search for the missing flight MH370, Fugro acquired the largest extent of high resolution bathymetry in the southern Indian Ocean to date. These recently released multibeam echosounder (MBES) backscatter, bathymetry, water column, and sub-bottom profiler data reveal additional insights into the characteristics of the Indian Ocean seafloor and the geologic and oceanographic processes that shaped it. The mapping is at a sufficient resolution to examine relict spreading texture such as fracture zones, pseudofaults, failed propogating rifts, devals (deviations from axial linearity), etc. In this presentation, we will highlight several prominent regional seafloor features, and illustrate insights gained by integrating MBES backscatter and water column data with bathymetric analyses. Backscatter data to the north of the southern flank of Broken Ridge illustrate the complexity to which sediment has been reworked downslope where intricate patterns of low backscatter intensities are observed. Here, exposed rocks form prominent high backscatter reflectors amid the surrounding low backscatter sediments. The lateral extent of high backscatter intensity reflectors south of the Diamantina reveals the expansiveness of exposed igneous rocks that resulted from seafloor spreading. Volcanic features, including off-axis volcanoes and leaky transforms are also interpreted as high backscatter anomalies in the tectonic speading fabric to the north of the Geelvinck fracture zone, towards the southern extent of the dataset. These and other examples show that by integrating the entire suite of data collected by MBES systems, more detailed interpretations of the geologic processes that shaped the seafloor may be gained than by examination of bathymetry alone.

Development of thin sensors and a novel interconnection technology for the upgrade of the ATLAS pixel system

Energy Technology Data Exchange (ETDEWEB)

Andricek, L. [Max-Planck-Institut Halbleiterlabor, Otto Hahn Ring 6, 81739 Muenchen (Germany); Beimforde, M., E-mail: mibei@mpp.mpg.de [Max-Planck-Institut fuer Physik, Foehringer Ring 6, 80805 Muenchen (Germany); Macchiolo, A. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, 80805 Muenchen (Germany); Moser, H.-G. [Max-Planck-Institut Halbleiterlabor, Otto Hahn Ring 6, 81739 Muenchen (Germany); Nisius, R. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, 80805 Muenchen (Germany); Richter, R.H. [Max-Planck-Institut Halbleiterlabor, Otto Hahn Ring 6, 81739 Muenchen (Germany)

2011-04-21

A new pixel module concept is presented utilizing thin sensors and a novel vertical integration technique for the ATLAS pixel detector in view of the foreseen LHC luminosity upgrades. A first set of pixel sensors with active thicknesses of 75 and 150{mu}m has been produced from wafers of standard thickness using a thinning process developed at the Max-Planck-Institut Halbleiterlabor (HLL) and the Max-Planck-Institut fuer Physik (MPP). Pre-irradiation characterizations of these sensors show a very good device yield and high break down voltage. First proton irradiations up to a fluence of 10{sup 15} n{sub eq} cm{sup -2} have been carried out and their impact on the electrical properties of thin sensors has been studied. The novel ICV-SLID vertical integration technology will allow for routing signals vertically to the back side of the readout chips. With this, four-side buttable detector devices with an increased active area fraction are made possible. A first production of SLID test structures was performed and showed a high connection efficiency for different pad sizes and a mild sensitivity to disturbances of the surface planarity.

Development of thin sensors and a novel interconnection technology for the upgrade of the ATLAS pixel system

International Nuclear Information System (INIS)

Andricek, L.; Beimforde, M.; Macchiolo, A.; Moser, H.-G.; Nisius, R.; Richter, R.H.

2011-01-01

A new pixel module concept is presented utilizing thin sensors and a novel vertical integration technique for the ATLAS pixel detector in view of the foreseen LHC luminosity upgrades. A first set of pixel sensors with active thicknesses of 75 and 150μm has been produced from wafers of standard thickness using a thinning process developed at the Max-Planck-Institut Halbleiterlabor (HLL) and the Max-Planck-Institut fuer Physik (MPP). Pre-irradiation characterizations of these sensors show a very good device yield and high break down voltage. First proton irradiations up to a fluence of 10 15 n eq cm -2 have been carried out and their impact on the electrical properties of thin sensors has been studied. The novel ICV-SLID vertical integration technology will allow for routing signals vertically to the back side of the readout chips. With this, four-side buttable detector devices with an increased active area fraction are made possible. A first production of SLID test structures was performed and showed a high connection efficiency for different pad sizes and a mild sensitivity to disturbances of the surface planarity.

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.

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).

Modelling of the over-exposed pixel area of CCD cameras caused by laser dazzling

NARCIS (Netherlands)

Benoist, K.W.; Schleijpen, R.M.A.

2014-01-01

A simple model has been developed and implemented in Matlab code, predicting the over-exposed pixel area of cameras caused by laser dazzling. Inputs of this model are the laser irradiance on the front optics of the camera, the Point Spread Function (PSF) of the used optics, the integration time of

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.

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.

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.

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.

Nuclear plants gain integrated information systems

International Nuclear Information System (INIS)

Villavicencio-Ramirez, A.; Rodriquez-Alvarez, J.M.

1994-01-01

With the objective of simplifying the complex mesh of computing devices employed within nuclear power plants, modern technology and integration techniques are being used to form centralized (but backed up) databases and distributed processing and display networks. Benefits are immediate as a result of the integration and the use of standards. The use of a unique data acquisition and database subsystem optimizes the high costs of engineering, as this task is done only once for the life span of the system. This also contributes towards a uniform user interface and allows for graceful expansion and maintenance. This article features an integrated information system, Sistema Integral de Informacion de Proceso (SIIP). The development of this system enabled the Laguna Verde Nuclear Power plant to fully use the already existing universe of signals and its related engineering during all plant conditions, namely, start up, normal operation, transient analysis, and emergency operation. Integrated systems offer many advantages over segregated systems, and this experience should benefit similar development efforts in other electric power utilities, not only for nuclear but also for other types of generating plants

Random On-Board Pixel Sampling (ROPS) X-Ray Camera

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhehui [Los Alamos; Iaroshenko, O. [Los Alamos; Li, S. [Los Alamos; Liu, T. [Fermilab; Parab, N. [Argonne (main); Chen, W. W. [Purdue U.; Chu, P. [Los Alamos; Kenyon, G. [Los Alamos; Lipton, R. [Fermilab; Sun, K.-X. [Nevada U., Las Vegas

2017-09-25

Recent advances in compressed sensing theory and algorithms offer new possibilities for high-speed X-ray camera design. In many CMOS cameras, each pixel has an independent on-board circuit that includes an amplifier, noise rejection, signal shaper, an analog-to-digital converter (ADC), and optional in-pixel storage. When X-ray images are sparse, i.e., when one of the following cases is true: (a.) The number of pixels with true X-ray hits is much smaller than the total number of pixels; (b.) The X-ray information is redundant; or (c.) Some prior knowledge about the X-ray images exists, sparse sampling may be allowed. Here we first illustrate the feasibility of random on-board pixel sampling (ROPS) using an existing set of X-ray images, followed by a discussion about signal to noise as a function of pixel size. Next, we describe a possible circuit architecture to achieve random pixel access and in-pixel storage. The combination of a multilayer architecture, sparse on-chip sampling, and computational image techniques, is expected to facilitate the development and applications of high-speed X-ray camera technology.

Steganography based on pixel intensity value decomposition

Science.gov (United States)

Abdulla, Alan Anwar; Sellahewa, Harin; Jassim, Sabah A.

2014-05-01

This paper focuses on steganography based on pixel intensity value decomposition. A number of existing schemes such as binary, Fibonacci, Prime, Natural, Lucas, and Catalan-Fibonacci (CF) are evaluated in terms of payload capacity and stego quality. A new technique based on a specific representation is proposed to decompose pixel intensity values into 16 (virtual) bit-planes suitable for embedding purposes. The proposed decomposition has a desirable property whereby the sum of all bit-planes does not exceed the maximum pixel intensity value, i.e. 255. Experimental results demonstrate that the proposed technique offers an effective compromise between payload capacity and stego quality of existing embedding techniques based on pixel intensity value decomposition. Its capacity is equal to that of binary and Lucas, while it offers a higher capacity than Fibonacci, Prime, Natural, and CF when the secret bits are embedded in 1st Least Significant Bit (LSB). When the secret bits are embedded in higher bit-planes, i.e., 2nd LSB to 8th Most Significant Bit (MSB), the proposed scheme has more capacity than Natural numbers based embedding. However, from the 6th bit-plane onwards, the proposed scheme offers better stego quality. In general, the proposed decomposition scheme has less effect in terms of quality on pixel value when compared to most existing pixel intensity value decomposition techniques when embedding messages in higher bit-planes.

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.

Thin n-in-p pixel sensors and the SLID-ICV vertical integration technology for the ATLAS upgrade at the HL-LHC

CERN Document Server

Macchiolo, A

2013-01-01

The R&D activity presented is focused on the development of new modules for the upgrade of the ATLAS pixel system at the High Luminosity LHC (HL-LHC). The performance after irradiation of n-in-p pixel sensors of different active thicknesses is studied, together with an investigation of a novel interconnection technique offered by the Fraunhofer Institute EMFT in Munich, the Solid-Liquid-InterDiffusion (SLID), which is an alternative to the standard solder bump-bonding. The pixel modules are based on thin n-in-p sensors, with an active thickness of 75 um or 150 um, produced at the MPI Semiconductor Laboratory (MPI HLL) and on 100 um thick sensors with active edges, fabricated at VTT, Finland. Hit efficiencies are derived from beam test data for thin devices irradiated up to a fluence of 4e15 neq/cm^2. For the active edge devices, the charge collection properties of the edge pixels before irradiation is discussed in detail, with respect to the inner ones, using measurements with radioactive sources. Beyond ...

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.

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.

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...

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.

High-speed x-ray imaging with the Keck pixel array detector (Keck PAD) for time-resolved experiments at synchrotron sources

Energy Technology Data Exchange (ETDEWEB)

Philipp, Hugh T., E-mail: htp2@cornell.edu; Tate, Mark W.; Purohit, Prafull; Shanks, Katherine S.; Weiss, Joel T. [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY (United States); Chamberlain, Darol; Gruner, Sol M. [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY (United States); Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, NY (United States)

2016-07-27

Modern storage rings are readily capable of providing intense x-ray pulses, tens of picoseconds in duration, millions of times per second. Exploiting the temporal structure of these x-ray sources opens avenues for studying rapid structural changes in materials. Many processes (e.g. crack propagation, deformation on impact, turbulence, etc.) differ in detail from one sample trial to the next and would benefit from the ability to record successive x-ray images with single x-ray sensitivity while framing at 5 to 10 MHz rates. To this end, we have pursued the development of fast x-ray imaging detectors capable of collecting bursts of images that enable the isolation of single synchrotron bunches and/or bunch trains. The detector technology used is the hybrid pixel array detector (PAD) with a charge integrating front-end, and high-speed, in-pixel signal storage elements. A 384×256 pixel version, the Keck-PAD, with 150 µm × 150 µm pixels and 8 dedicated in-pixel storage elements is operational, has been tested at CHESS, and has collected data for compression wave studies. An updated version with 27 dedicated storage capacitors and identical pixel size has been fabricated.

Study and realization of pixelated APD Geiger photodetectors of very high sensitivity for Very High Energy gamma astronomy

International Nuclear Information System (INIS)

Jradi, K.

2010-07-01

Very High Energy gamma ray astronomy uses till now exclusively as detector the Photomultiplier Tube (PMT) to collect weak light flux of atmospheric showers. But an alternative is now emerging: Avalanche Photodiodes polarized in Geiger mode called 'Geiger-APD'. The PMT is a detector designed in the 70's which presents many advantages but also suffers from several drawbacks: size, weight, cost, sensitivity to magnetic field but especially difficulty to realize its pixelation in matrix. Geiger-APDs are semi-conductor devices made of PN junction integrated in a special technology to detect very low light flux, thanks to the polarization beyond the avalanche voltage. Geiger-APD presents very high photoelectron gain (∼106) strongly dependant on the polarization voltage beyond avalanche. These photodiodes present many advantages with respect to PMT, mainly as concerns miniaturization for applications based on imaging, such as the detection of Cerenkov flashes in gamma ray astronomy. In this thesis, we present the study, the design and the realization of a technological structure, based on Silicon. This structure has shown reliability to detect weak luminous flux with breakdown voltage at 12 V and dark current below 10 pA at breakdown. We also developed several models, physical and electrical, necessary to the technological optimization, as well to the development of control and readout circuits, i.e. the basis of any imaging technology. The work presented here consists in the study, the design and the realization of a matrix of high sensitivity pixels. A project of a Cerenkov telescope based on this innovative technology is also presented. (author)

Adaptive pixel-to-pixel projection intensity adjustment for measuring a shiny surface using orthogonal color fringe pattern projection

Science.gov (United States)

Chen, Chao; Gao, Nan; Wang, Xiangjun; Zhang, Zonghua

2018-05-01

Three-dimensional (3D) shape measurement based on fringe pattern projection techniques has been commonly used in various fields. One of the remaining challenges in fringe pattern projection is that camera sensor saturation may occur if there is a large range of reflectivity variation across the surface that causes measurement errors. To overcome this problem, a novel fringe pattern projection method is proposed to avoid image saturation and maintain high-intensity modulation for measuring shiny surfaces by adaptively adjusting the pixel-to-pixel projection intensity according to the surface reflectivity. First, three sets of orthogonal color fringe patterns and a sequence of uniform gray-level patterns with different gray levels are projected onto a measured surface by a projector. The patterns are deformed with respect to the object surface and captured by a camera from a different viewpoint. Subsequently, the optimal projection intensity at each pixel is determined by fusing different gray levels and transforming the camera pixel coordinate system into the projector pixel coordinate system. Finally, the adapted fringe patterns are created and used for 3D shape measurement. Experimental results on a flat checkerboard and shiny objects demonstrate that the proposed method can measure shiny surfaces with high accuracy.

High-voltage pixel sensors for ATLAS upgrade

Energy Technology Data Exchange (ETDEWEB)

Perić, I., E-mail: ivan.peric@ziti.uni-heidelberg.de [Heidelberg University, Institute of Computer Engineering, Mannheim (Germany); Kreidl, C.; Fischer, P. [Heidelberg University, Institute of Computer Engineering, Mannheim (Germany); Bompard, F.; Breugnon, P.; Clemens, J.-C.; Fougeron, D.; Liu, J.; Pangaud, P.; Rozanov, A.; Barbero, M. [CPPM, Marseille (France); Feigl, S.; Capeans, M.; Ferrere, D.; Pernegger, H.; Ristic, B. [CERN, Geneve (Switzerland); Muenstermann, D.; Gonzalez Sevilla, S.; La Rosa, A.; Miucci, A. [University of Geneve (Switzerland); and others

2014-11-21

The high-voltage (HV-) CMOS pixel sensors offer several good properties: a fast charge collection by drift, the possibility to implement relatively complex CMOS in-pixel electronics and the compatibility with commercial processes. The sensor element is a deep n-well diode in a p-type substrate. The n-well contains CMOS pixel electronics. The main charge collection mechanism is drift in a shallow, high field region, which leads to a fast charge collection and a high radiation tolerance. We are currently evaluating the use of the high-voltage detectors implemented in 180 nm HV-CMOS technology for the high-luminosity ATLAS upgrade. Our approach is replacing the existing pixel and strip sensors with the CMOS sensors while keeping the presently used readout ASICs. By intelligence we mean the ability of the sensor to recognize a particle hit and generate the address information. In this way we could benefit from the advantages of the HV sensor technology such as lower cost, lower mass, lower operating voltage, smaller pitch, smaller clusters at high incidence angles. Additionally we expect to achieve a radiation hardness necessary for ATLAS upgrade. In order to test the concept, we have designed two HV-CMOS prototypes that can be readout in two ways: using pixel and strip readout chips. In the case of the pixel readout, the connection between HV-CMOS sensor and the readout ASIC can be established capacitively.

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.

Super-pixel extraction based on multi-channel pulse coupled neural network

Science.gov (United States)

Xu, GuangZhu; Hu, Song; Zhang, Liu; Zhao, JingJing; Fu, YunXia; Lei, BangJun

2018-04-01

Super-pixel extraction techniques group pixels to form over-segmented image blocks according to the similarity among pixels. Compared with the traditional pixel-based methods, the image descripting method based on super-pixel has advantages of less calculation, being easy to perceive, and has been widely used in image processing and computer vision applications. Pulse coupled neural network (PCNN) is a biologically inspired model, which stems from the phenomenon of synchronous pulse release in the visual cortex of cats. Each PCNN neuron can correspond to a pixel of an input image, and the dynamic firing pattern of each neuron contains both the pixel feature information and its context spatial structural information. In this paper, a new color super-pixel extraction algorithm based on multi-channel pulse coupled neural network (MPCNN) was proposed. The algorithm adopted the block dividing idea of SLIC algorithm, and the image was divided into blocks with same size first. Then, for each image block, the adjacent pixels of each seed with similar color were classified as a group, named a super-pixel. At last, post-processing was adopted for those pixels or pixel blocks which had not been grouped. Experiments show that the proposed method can adjust the number of superpixel and segmentation precision by setting parameters, and has good potential for super-pixel extraction.

Advances in the development of pixel detector for the SuperB Silicon Vertex Tracker

Energy Technology Data Exchange (ETDEWEB)

Paoloni, E., E-mail: eugenio.paoloni@pi.infn.it [Università degli Studi di Pisa (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Pisa (Italy); Comotti, D. [Università degli Studi di Bergamo (Italy); Manghisoni, M.; Re, V.; Traversi, G. [Università degli Studi di Bergamo (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Pavia (Italy); Fabbri, L.; Gabrielli, A. [Università degli Studi di Bologna (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bologna (Italy); Giorgi, F.; Pellegrini, G.; Sbarra, C. [Istituto Nazionale di Fisica Nucleare, Sezione di Bologna (Italy); Semprini-Cesari, N.; Valentinetti, S.; Villa, M.; Zoccoli, A. [Università degli Studi di Bologna (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bologna (Italy); Berra, A.; Lietti, D.; Prest, M. [Università dell' Insubria, Como (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca (Italy); Bevan, A. [School of Physics and Astronomy, Queen Mary University of London, London E1 4NS (United Kingdom); Wilson, F. [STFC Rutherford Appleton Laboratory, Harwell, Oxford Didcot OX11 0QX (United Kingdom); Beck, G. [School of Physics and Astronomy, Queen Mary University of London, London E1 4NS (United Kingdom); and others

2013-12-11

The latest advances in the design and characterization of several pixel sensors developed to satisfy the very demanding requirements of the innermost layer of the SuperB Silicon Vertex Tracker will be presented in this paper. The SuperB machine is an electron positron collider operating at the ϒ(4S) peak to be built in the very near future by the Cabibbo Lab consortium. A pixel detector based on extremely thin, radiation hard devices able to cope with rate in the tens of MHz/cm{sup 2} range will be the optimal solution for the upgrade of the inner layer of the SuperB tracking system. At present several options with different levels of maturity are being investigated to understand advantages and potential issues of the different technologies: thin hybrid pixels, Deep N-Well CMOS MAPS, INMAPS CMOS MAPS featuring a quadruple well and high resistivity substrates and CMOS MAPS realized with Vertical Integration technology. The newest results from beam test, the outcomes of the radiation damage studies and the laboratory characterization of the latest prototypes will be reported.

Advances in the development of pixel detector for the SuperB Silicon Vertex Tracker

International Nuclear Information System (INIS)

Paoloni, E.; Comotti, D.; Manghisoni, M.; Re, V.; Traversi, G.; Fabbri, L.; Gabrielli, A.; Giorgi, F.; Pellegrini, G.; Sbarra, C.; Semprini-Cesari, N.; Valentinetti, S.; Villa, M.; Zoccoli, A.; Berra, A.; Lietti, D.; Prest, M.; Bevan, A.; Wilson, F.; Beck, G.

2013-01-01

The latest advances in the design and characterization of several pixel sensors developed to satisfy the very demanding requirements of the innermost layer of the SuperB Silicon Vertex Tracker will be presented in this paper. The SuperB machine is an electron positron collider operating at the ϒ(4S) peak to be built in the very near future by the Cabibbo Lab consortium. A pixel detector based on extremely thin, radiation hard devices able to cope with rate in the tens of MHz/cm 2 range will be the optimal solution for the upgrade of the inner layer of the SuperB tracking system. At present several options with different levels of maturity are being investigated to understand advantages and potential issues of the different technologies: thin hybrid pixels, Deep N-Well CMOS MAPS, INMAPS CMOS MAPS featuring a quadruple well and high resistivity substrates and CMOS MAPS realized with Vertical Integration technology. The newest results from beam test, the outcomes of the radiation damage studies and the laboratory characterization of the latest prototypes will be reported

A Medipix2-based imaging system for digital mammography with silicon pixel detectors

CERN Document Server

Bisogni, M G; Fantacci, M E; Mettivier, G; Montesi, M C; Novelli, M; Quattrocchi, M; Rosso, V; Russo, P; Stefanini, A

2004-01-01

In this paper we present the first tests of a digital imaging system based on a silicon pixel detector bump-bonded to an integrated circuit operating in single photon counting mode. The X-rays sensor is a 300 mu m thick silicon, 14 by 14 mm/sup 2/, upon which a matrix of 256 * 256 pixels has been built. The read-out chip, named MEDIPIX2, has been developed at CERN within the MEDIPIX2 Collaboration and it is composed by a matrix of 256 * 256 cells, 55 * 55 mu m/sup 2/. The spatial resolution properties of the system have been assessed by measuring the square wave resolution function (SWRF) and first images of a standard mammographic phantom were acquired using a radiographic tube in the clinical irradiation condition. (5 refs).

Steganography on quantum pixel images using Shannon entropy

Science.gov (United States)

Laurel, Carlos Ortega; Dong, Shi-Hai; Cruz-Irisson, M.

2016-07-01

This paper presents a steganographical algorithm based on least significant bit (LSB) from the most significant bit information (MSBI) and the equivalence of a bit pixel image to a quantum pixel image, which permits to make the information communicate secretly onto quantum pixel images for its secure transmission through insecure channels. This algorithm offers higher security since it exploits the Shannon entropy for an image.

Characterization of Ir/Au pixel TES

International Nuclear Information System (INIS)

Kunieda, Y.; Takahashi, H.; Zen, N.; Damayanthi, R.M.T.; Mori, F.; Fujita, K.; Nakazawa, M.; Fukuda, D.; Ohkubo, M.

2006-01-01

Signal shapes and noise characteristics of an asymmetrical ten-pixel Ir/Au-TES have been studied. The asymmetric design may be effective to realize an imaging spectrometer. Distinct two exponential decays observed for X-ray events are consistent with a two-step R-T curve. A theoretical thermal model for noise in multi-pixel devices reasonably explains the experimental data

Few-Layer MoS2-Organic Thin-Film Hybrid Complementary Inverter Pixel Fabricated on a Glass Substrate.

Science.gov (United States)

Lee, Hee Sung; Shin, Jae Min; Jeon, Pyo Jin; Lee, Junyeong; Kim, Jin Sung; Hwang, Hyun Chul; Park, Eunyoung; Yoon, Woojin; Ju, Sang-Yong; Im, Seongil

2015-05-13

Few-layer MoS2-organic thin-film hybrid complementary inverters demonstrate a great deal of device performance with a decent voltage gain of ≈12, a few hundred pW power consumption, and 480 Hz switching speed. As fabricated on glass, this hybrid CMOS inverter operates as a light-detecting pixel as well, using a thin MoS2 channel. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

4T CMOS Active Pixel Sensors under Ionizing Radiation

NARCIS (Netherlands)

Tan, J.

2013-01-01

This thesis investigates the ionizing radiation effects on 4T pixels and the elementary in-pixel test devices with regard to the electrical performance and the optical performance. In addition to an analysis of the macroscopic pixel parameter degradation, the radiation-induced degradation mechanisms

Selecting Pixels for High-Precision Photometry in the Kepler Mission

Science.gov (United States)

Bryson, Steve; Jenkins, J.; Caldwell, D.; Koch, D.; Borucki, W.

2007-12-01

The Kepler Mission is designed to discover and characterize the frequency of Earth-size planets in the habitable zone of solar-like stars by observing 100,000 main-sequence stars in a 100 square degree field of view (FOV). Kepler's transit detection method uses a long photometric time series for each target star. Each data point is created by summing several pixels.The data are co-added and stored at a 30 minute cadence that is stored for monthly downlink. Memory and bandwidth constraints prevent the storage of all 95 million pixels in the photometer, so pixels of interest are assigned to each target. We describe the automated method by which each transit target is assigned a set of pixels that are optimal for high precision photometry. This method relies on synthetic images based on the Kepler input catalog combined with a direct measurement of the Kepler systempoint spread function. We cover the PSF measurement process, the rendering of the synthetic image, and the use of the synthetic image to determine the contribution of each pixel to a target's signal-to-noise ratio. The optimal pixels for a target are defined as those pixels which maximize that target's signal-to-noise ratio. Our method includes models of the noise associated with pixel response variations and for spacecraft motion. We describe the process that is used to identify appropriate pixels for modeling the background as well as pixel management, including the specification of pixels for non-transit targets. Funding for this mission provided by NASA's Discovery Program Office, SMD.

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...

Spectral response characterization of CdTe sensors of different pixel size with the IBEX ASIC

Science.gov (United States)

Zambon, P.; Radicci, V.; Trueb, P.; Disch, C.; Rissi, M.; Sakhelashvili, T.; Schneebeli, M.; Broennimann, C.

2018-06-01

We characterized the spectral response of CdTe sensors with different pixel sizes - namely 75, 150 and 300 μm - bonded to the latest generation IBEX single photon counting ASIC developed at DECTRIS, to detect monochromatic X-ray energy in the range 10-60 keV. We present a comparison of pulse height spectra recorded for several energies, showing the dependence on the pixel size of the non-trivial atomic fluorescence and charge sharing effects that affect the detector response. The extracted energy resolution, in terms of full width at half maximum or FWHM, ranges from 1.5 to 4 keV according to the pixel size and chip configuration. We devoted a careful analysis to the Quantum Efficiency and to the Spectral Efficiency - a newly-introduced measure that quantifies the impact of fluorescence and escape phenomena on the spectrum integrity in high- Z material based detectors. We then investigated the influence of the photon flux on the aforementioned quantities up to 180 ṡ 106 cts/s/mm2 and 50 ṡ 106 cts/s/mm2 for the 150 μm and 300 μm pixel case, respectively. Finally, we complemented the experimental data with analytical and with Monte Carlo simulations - taking into account the stochastic nature of atomic fluorescence - with an excellent agreement.

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.

X-ray imaging characterization of active edge silicon pixel sensors

International Nuclear Information System (INIS)

Ponchut, C; Ruat, M; Kalliopuska, J

2014-01-01

The aim of this work was the experimental characterization of edge effects in active-edge silicon pixel sensors, in the frame of X-ray pixel detectors developments for synchrotron experiments. We produced a set of active edge pixel sensors with 300 to 500 μm thickness, edge widths ranging from 100 μm to 150 μm, and n or p pixel contact types. The sensors with 256 × 256 pixels and 55 × 55 μm 2 pixel pitch were then bump-bonded to Timepix readout chips for X-ray imaging measurements. The reduced edge widths makes the edge pixels more sensitive to the electrical field distribution at the sensor boundaries. We characterized this effect by mapping the spatial response of the sensor edges with a finely focused X-ray synchrotron beam. One of the samples showed a distortion-free response on all four edges, whereas others showed variable degrees of distortions extending at maximum to 300 micron from the sensor edge. An application of active edge pixel sensors to coherent diffraction imaging with synchrotron beams is described

Plasmonic nanospherical dimers for color pixels

KAUST Repository

Alrasheed, Salma

2018-04-20

Display technologies are evolving more toward higher resolution and miniaturization. Plasmonic color pixels can offer solutions to realize such technologies due to their sharp resonances and selective scattering and absorption at particular wavelengths. Metal nanosphere dimers are capable of supporting plasmon resonances that can be tuned to span the entire visible spectrum. In this article, we demonstrate numerically bright color pixels that are highly polarized and broadly tuned using periodic arrays of metal nanosphere dimers on a glass substrate. We show that it is possible to obtain RGB pixels in the reflection mode. The longitudinal plasmon resonance of nanosphere dimers along the axis of the dimer is the main contributor to the color of the pixel, while far-field diffractive coupling further enhances and tunes the plasmon resonance. The computational method used is the finite-difference time-domain method. The advantages of this approach include simplicity of the design, bright coloration, and highly polarized function. In addition, we show that it is possible to obtain different colors by varying the angle of incidence, the periodicity, the size of the dimer, the gap, and the substrate thickness.

Theory and applications of structured light single pixel imaging

Science.gov (United States)

Stokoe, Robert J.; Stockton, Patrick A.; Pezeshki, Ali; Bartels, Randy A.

2018-02-01

Many single-pixel imaging techniques have been developed in recent years. Though the methods of image acquisition vary considerably, the methods share unifying features that make general analysis possible. Furthermore, the methods developed thus far are based on intuitive processes that enable simple and physically-motivated reconstruction algorithms, however, this approach may not leverage the full potential of single-pixel imaging. We present a general theoretical framework of single-pixel imaging based on frame theory, which enables general, mathematically rigorous analysis. We apply our theoretical framework to existing single-pixel imaging techniques, as well as provide a foundation for developing more-advanced methods of image acquisition and reconstruction. The proposed frame theoretic framework for single-pixel imaging results in improved noise robustness, decrease in acquisition time, and can take advantage of special properties of the specimen under study. By building on this framework, new methods of imaging with a single element detector can be developed to realize the full potential associated with single-pixel imaging.

Development of an ASD IC for the Micro Pixel Chamber

CERN Document Server

Orito, R; Kubo, H; Miuchi, K; Nagayoshi, T; Okada, Y; Takada, A; Takeda, A; Tanimori, T; Ueno, M

2004-01-01

A new amplifier-shaper-discriminator (ASD) chip was designed and manufactured for the Micro Pixel Chamber ($\\mu$-PIC). The design of this ASD IC is based on the ASD IC (TGC-ASD) for the Thin Gap Chamber in the LHC Atlas Experiment. The decay time constant of the preamplifier is 5-times longer than that of the TGC-ASD, and some other modifications have been made in order to improve the signal-to-noise ratio of the $\\mu$-PIC. The ASD IC uses SONY Analog Master Slice bipolar technology. The IC contains 4 channels in a QFP48 package. The decay time constant of the preamplifier is 80 ns and its gain is approximately 0.8 V/pC. The output from the preamplifier is received by a shaper (main-amplifier) with a gain of 7. A baseline restoration circuit is incorporated in the main-amplifier, and the current used for the baseline restoration is 5-times smaller than that of the TGC-ASD. The threshold voltage for the discriminator section is common to the 4 channels and their digital output level is LVDS-compatible. The ASD...

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

SVM Pixel Classification on Colour Image Segmentation

Science.gov (United States)

Barui, Subhrajit; Latha, S.; Samiappan, Dhanalakshmi; Muthu, P.

2018-04-01

The aim of image segmentation is to simplify the representation of an image with the help of cluster pixels into something meaningful to analyze. Segmentation is typically used to locate boundaries and curves in an image, precisely to label every pixel in an image to give each pixel an independent identity. SVM pixel classification on colour image segmentation is the topic highlighted in this paper. It holds useful application in the field of concept based image retrieval, machine vision, medical imaging and object detection. The process is accomplished step by step. At first we need to recognize the type of colour and the texture used as an input to the SVM classifier. These inputs are extracted via local spatial similarity measure model and Steerable filter also known as Gabon Filter. It is then trained by using FCM (Fuzzy C-Means). Both the pixel level information of the image and the ability of the SVM Classifier undergoes some sophisticated algorithm to form the final image. The method has a well developed segmented image and efficiency with respect to increased quality and faster processing of the segmented image compared with the other segmentation methods proposed earlier. One of the latest application result is the Light L16 camera.

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.

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.

Dichromatic Gray Pixel for Camera-agnostic Color Constancy

OpenAIRE

Qian, Yanlin; Chen, Ke; Nikkanen, Jarno; Kämäräinen, Joni-Kristian; Matas, Jiri

2018-01-01

We propose a novel statistical color constancy method, especially suitable for the Camera-agnostic Color Constancy, i.e. the scenario where nothing is known a priori about the capturing devices. The method, called Dichromatic Gray Pixel, or DGP, relies on a novel gray pixel detection algorithm derived using the Dichromatic Reflection Model. DGP is suitable for camera-agnostic color constancy since varying devices are set to make achromatic pixels look gray under standard neutral illumination....

Direct Integration of Dynamic Emissive Displays into Knitted Fabric Structures

Science.gov (United States)

Bellingham, Alyssa

electroluminescence that occur where the conductive fibers contact the EL fibers. A passive matrix addressing scheme was used to apply a voltage to each pixel individually, creating a display capable of dynamically communicating information. Optical measurements of the intensity and color of emitted light were used to quantify the performance of the display and compare it to state-of-the-art display technologies. The charge-voltage (Q-V) electrical characterization technique is used to gain information about the ACPEL fiber device operation, and mechanical tests were performed to determine the effect everyday wear and tear would have on the performance of the display. The presented textile display structure and method of producing fibers with individual sections of electroluminescence addresses the shortcomings in existing textile display technology and provides a route to directly integrated communicative textiles for applications ranging from biomedical research and monitoring to fashion. An extensive discussion of the materials and methods of production needed to scale this textile display technology and incorporate it into wearable applications is presented.

Active pixel sensors: The sensor of choice for future space applications

OpenAIRE

Leijtens, J.; Theuwissen, A.; Rao, P.R.; Wang, X.; Xie, N.

2007-01-01

It is generally known that active pixel sensors (APS) have a number of advantages over CCD detectors if it comes to cost for mass production, power consumption and ease of integration. Nevertheless, most space applications still use CCD detectors because they tend to give better performance and have a successful heritage. To this respect a change may be at hand with the advent of deep sub-micron processed APS imagers (< 0.25-micron feature size). Measurements performed on test structures at t...

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}.

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 .

Quality control on planar n-in-n pixel sensors — Recent progress of ATLAS planar pixel sensors

International Nuclear Information System (INIS)

Klingenberg, R.

2013-01-01

To extend the physics reach of the Large Hadron Collider (LHC), upgrades to the accelerator are planned which will increase the peak luminosity by a factor 5–10. To cope with the increased occupancy and radiation damage, the ATLAS experiment plans to introduce an all-silicon inner tracker with the high luminosity upgrade (HL-LHC). To investigate the suitability of pixel sensors using the proven planar technology for the upgraded tracker, the ATLAS Upgrade Planar Pixel Sensor (PPS) R and D Project was established. Main areas of research are the performance of planar pixel sensors at highest fluences, the exploration of possibilities for cost reduction to enable the instrumentation of large areas, the achievement of slim or active edges to provide low geometric inefficiencies without the need for shingling of modules and the investigation of the operation of highly irradiated sensors at low thresholds to increase the efficiency. The Insertable b-layer (IBL) is the first upgrade project within the ATLAS experiment and will employ a new detector layer consisting of silicon pixel sensors, which were improved and prototyped in the framework of the planar pixel sensor R and D project. A special focus of this paper is the status of the development and testing of planar n-in-n pixel sensors including the quality control of the on-going series production and postprocessing of sensor wafers. A high yield of produced planar sensor wafers and FE-I4 double chip sensors after first steps of post-processing including under bump metallization and dicing is observed. -- Highlights: ► Prototypes of irradiated planar n-in-n sensors have been successfully tested under laboratory conditions. ► A quality assurance programme on the series production of planar sensors for the IBL has started. ► A high yield of double chip sensors during the series production is observed which are compatible to the specifications to this detector component.

Research and Development of Monolithic Active Pixel Sensors for the Detection of the Elementary Particles

International Nuclear Information System (INIS)

Li, Y.

2007-09-01

In order to develop high spatial resolution and readout speed vertex detectors for the future International Linear Collider (ILC), fast CMOS Monolithic Active Pixel Sensors (MAPS) are studied on this work. Two prototypes of MAPS, MIMOSA 8 and MIMOSA 16, based on the same micro-electronic architecture were developed in CMOS processes with different thickness of epitaxial layer. The size of pixel matrix is 32 x 128: 8 columns of the pixel array are readout directly with analog outputs and the other 24 columns are connected to the column level auto-zero discriminators. The Correlated Double Sampling (CDS) structures are successfully implemented inside pixel and discriminator. The photo diode type pixels with different diode sizes are used in these prototypes. With a 55 Fe X-ray radioactive source, the important parameters, such as Temporal Noise, Fixed Pattern Noise (FPN), Signal-to-Noise Ratio (SNR), Charge-to-Voltage conversion Factor (CVF) and Charge Collection Efficiency (CCE), are studied as function of readout speed and diode size. For MIMOSA 8, the effect of fast neutrons irradiation is also. Two beam tests campaigns were made: at DESY with a 5 GeV electrons beam and at CERN with a 180 GeV pions beam. Detection Efficiency and Spatial Resolution are studied in function of the discriminator threshold. For these two parameters, the influences of diode size and SNR of the central pixel of a cluster are also discussed. In order to improve the spatial resolution of the digital outputs, a very compact (25 μm x 1 mm) and low consumption (300 μW) column level ADC is designed in AMS 0.35 μm OPTO process. Based on successive approximation architecture, the auto-offset cancellation structure is integrated. A new column level auto-zero discriminator using static latch is also designed. (author)

Gain Enhanced LTCC System-on-Package for UMRR Applications

KAUST Repository

Shamim, Atif; Ghaffar, Farhan Abdul; Khalid, Muhammad Umair; Salama, Khaled N.

2014-01-01

An apparatus, system, and method for Gain Enhanced LTCC System-on-Package radar sensor. The sensor includes a substrate and an integrated circuit coupled to the substrate, where the integrated circuit is configured to transmit and receive radio frequency (RF) signals. An antenna may be coupled to the integrated circuit and a lens may be coupled to the antenna. The lens may be configured to enhance the gain of the sensor.

Gain Enhanced LTCC System-on-Package for UMRR Applications

KAUST Repository

Shamim, Atif

2014-10-14

An apparatus, system, and method for Gain Enhanced LTCC System-on-Package radar sensor. The sensor includes a substrate and an integrated circuit coupled to the substrate, where the integrated circuit is configured to transmit and receive radio frequency (RF) signals. An antenna may be coupled to the integrated circuit and a lens may be coupled to the antenna. The lens may be configured to enhance the gain of the sensor.

Development of a two-dimensional ASIC for hard X-ray spectroscopy and imaging with a CdTe pixel detector

International Nuclear Information System (INIS)

Hiruta, Tatsuro; Tamura, K.; Ikeda, H.; Nakazawa, K.; Takasima, T.; Takahashi, T.

2006-01-01

We are developing a two-dimensional analog ASIC for the readout of pixel sensors based on silicon (Si) or cadmium telluride (CdTe) for spectroscopic imaging observations in the X-ray and gamma-ray regions. The aim for the ASIC is to obtain a low-noise performance better than 100 electrons (rms) with self-triggering capabilities. As the first step of prototyping, we have fabricated several ASICs. We obtained an energy resolution of 5.4 keV (FWHM) for 81 keV gamma-rays from 133 Ba with a one-dimensional ASIC connected to a CdTe diode and also verified a readout architecture via a two-dimensional ASIC with 144 pixel channels. Based on the results obtained and experience gained through prototype ASICs, we are developing a 4096-channel two-dimensional analog ASIC

Production and characterization of SLID interconnected n-in-p pixel modules with 75 micron thin silicon sensors

CERN Document Server

Andricek, L; Macchiolo, A; Moser, H.G; Nisius, R; Richter, R.H; Terzo, S; Weigell, P

2014-01-01

The performance of pixel modules built from 75 micrometer thin silicon sensors and ATLAS read-out chips employing the Solid Liquid InterDiffusion (SLID) interconnection technology is presented. This technology, developed by the Fraunhofer EMFT, is a possible alternative to the standard bump-bonding. It allows for stacking of different interconnected chip and sensor layers without destroying the already formed bonds. In combination with Inter-Chip-Vias (ICVs) this paves the way for vertical integration. Both technologies are combined in a pixel module concept which is the basis for the modules discussed in this paper. Mechanical and electrical parameters of pixel modules employing both SLID interconnections and sensors of 75 micrometer thickness are covered. The mechanical features discussed include the interconnection efficiency, alignment precision and mechanical strength. The electrical properties comprise the leakage currents, tuning characteristics, charge collection, cluster sizes and hit efficiencies. T...

Production and Characterisation of SLID Interconnected n-in-p Pixel Modules with 75 Micrometer Thin Silicon Sensors

CERN Document Server

Andricek, L; Macchiolo, A.; Moser, H.-G.; Nisius, R.; Richter, R.H.; Terzo, S.; Weigell, P.

2014-01-01

The performance of pixel modules built from 75 micrometer thin silicon sensors and ATLAS read-out chips employing the Solid Liquid InterDiffusion (SLID) interconnection technology is presented. This technology, developed by the Fraunhofer EMFT, is a possible alternative to the standard bump-bonding. It allows for stacking of different interconnected chip and sensor layers without destroying the already formed bonds. In combination with Inter-Chip-Vias (ICVs) this paves the way for vertical integration. Both technologies are combined in a pixel module concept which is the basis for the modules discussed in this paper. Mechanical and electrical parameters of pixel modules employing both SLID interconnections and sensors of 75 micrometer thickness are covered. The mechanical features discussed include the interconnection efficiency, alignment precision and mechanical strength. The electrical properties comprise the leakage currents, tunability, charge collection, cluster sizes and hit efficiencies. Targeting at ...

Développement de la tomographie intra-vitale au K-edge avec la caméra à pixels hybrides XPAD3

OpenAIRE

Kronland-Martinet, C.

2015-01-01

The hybrid pixel camera XPAD3 integrated in the micro-CT PIXSCAN IIis a new devicedeveloped by the imXgam team at CPPM for which photon counting replaces charge integrationused in standard X-ray CT. This novel approach involves advantages, in particularthe absence of dark noise and the ability to set an energy threshold on each pixel of thedetected photons. This features has been exploited during this thesis work for standardsmall animal preclinical imaging and permitted to establish the fais...

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.

Characterization and simulation of the response of Multi-Pixel Photon Counters to low light levels

Energy Technology Data Exchange (ETDEWEB)

Vacheret, A. [Department of Physics, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Barker, G.J. [Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom); Dziewiecki, M. [Institute of Radioelectronics, Warsaw University of Technology, 15/19 Nowowiejska St., 00-665 Warsaw (Poland); Guzowski, P. [Department of Physics, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Haigh, M.D. [Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (United Kingdom); Hartfiel, B. [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Tower Drive, Baton Rouge, LA 70803 (United States); Izmaylov, A. [Institute for Nuclear Research RAS, 60 October Revolution Pr. 7A, 117312 Moscow (Russian Federation); Johnston, W. [Department of Physics, Colorado State University, Fort Collins, CO 80523 (United States); Khabibullin, M.; Khotjantsev, A.; Kudenko, Yu. [Institute for Nuclear Research RAS, 60 October Revolution Pr. 7A, 117312 Moscow (Russian Federation); Kurjata, R. [Institute of Radioelectronics, Warsaw University of Technology, 15/19 Nowowiejska St., 00-665 Warsaw (Poland); Kutter, T. [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Tower Drive, Baton Rouge, LA 70803 (United States); Lindner, T. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, Canada, BC V6T 1Z1 (Canada); Masliah, P. [Department of Physics, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Marzec, J. [Institute of Radioelectronics, Warsaw University of Technology, 15/19 Nowowiejska St., 00-665 Warsaw (Poland); Mineev, O.; Musienko, Yu. [Institute for Nuclear Research RAS, 60 October Revolution Pr. 7A, 117312 Moscow (Russian Federation); and others

2011-11-11

The calorimeter, range detector and active target elements of the T2K near detectors rely on the Hamamatsu Photonics Multi-Pixel Photon Counters (MPPCs) to detect scintillation light produced by charged particles. Detailed measurements of the MPPC gain, afterpulsing, crosstalk, dark noise, and photon detection efficiency for low light levels are reported. In order to account for the impact of the MPPC behavior on T2K physics observables, a simulation program has been developed based on these measurements. The simulation is used to predict the energy resolution of the detector.

Characterization and simulation of the response of Multi-Pixel Photon Counters to low light levels

International Nuclear Information System (INIS)

Vacheret, A.; Barker, G.J.; Dziewiecki, M.; Guzowski, P.; Haigh, M.D.; Hartfiel, B.; Izmaylov, A.; Johnston, W.; Khabibullin, M.; Khotjantsev, A.; Kudenko, Yu.; Kurjata, R.; Kutter, T.; Lindner, T.; Masliah, P.; Marzec, J.; Mineev, O.; Musienko, Yu.

2011-01-01

The calorimeter, range detector and active target elements of the T2K near detectors rely on the Hamamatsu Photonics Multi-Pixel Photon Counters (MPPCs) to detect scintillation light produced by charged particles. Detailed measurements of the MPPC gain, afterpulsing, crosstalk, dark noise, and photon detection efficiency for low light levels are reported. In order to account for the impact of the MPPC behavior on T2K physics observables, a simulation program has been developed based on these measurements. The simulation is used to predict the energy resolution of the detector.

An output amplitude configurable wideband automatic gain control with high gain step accuracy

International Nuclear Information System (INIS)

He Xiaofeng; Ye Tianchun; Mo Taishan; Ma Chengyan

2012-01-01

An output amplitude configurable wideband automatic gain control (AGC) with high gain step accuracy for the GNSS receiver is presented. The amplitude of an AGC is configurable in order to cooperate with baseband chips to achieve interference suppression and be compatible with different full range ADCs. And what's more, the gain-boosting technology is introduced and the circuit is improved to increase the step accuracy. A zero, which is composed by the source feedback resistance and the source capacity, is introduced to compensate for the pole. The AGC is fabricated in a 0.18 μm CMOS process. The AGC shows a 62 dB gain control range by 1 dB each step with a gain error of less than 0.2 dB. The AGC provides 3 dB bandwidth larger than 80 MHz and the overall power consumption is less than 1.8 mA, and the die area is 800 × 300 μm 2 . (semiconductor integrated circuits)

Access To The PMM's Pixel Database

Science.gov (United States)

Monet, D.; Levine, S.

1999-12-01

The U.S. Naval Observatory Flagstaff Station is in the process of enabling access to the Precision Measuring Machine (PMM) program's pixel database. The initial release will include the pixels from the PMM's scans of the Palomar Observatory Sky Survey I (POSS-I) -O and -E surveys, the Whiteoak Extension, the European Southern Observatory-R survey, the Science and Engineering Council-J, -EJ, and -ER surveys, and the Anglo- Australian Observatory-R survey. (The SERC-ER and AAO-R surveys are currently incomplete.) As time allows, access to the POSS-II -J, -F, and -N surveys, the Palomar Infrared Milky Way Atlas, the Yale/San Juan Southern Proper Motion survey, and plates rejected by various surveys will be added. (POSS-II -J and -F are complete, but -N was never finished.) Eventually, some 10 Tbytes of pixel data will be available. Due to funding and technology limitations, the initial interface will have only limited functionality, and access time will be slow since the archive is stored on Digital Linear Tape (DLT). Usage of the pixel data will be restricted to non-commercial, scientific applications, and agreements on copyright issues have yet to be finalized. The poster presentation will give the URL.

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.

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.

A pixel unit-cell targeting 16 ns resolution and radiation hardness in a column read-out particle vertex detector

International Nuclear Information System (INIS)

Wright, M.; Millaud, J.; Nygren, D.

1992-10-01

A pixel unit cell (PUC) circuit architecture, optimized for a column read out architecture, is reported. Each PUC contains an integrator, active filter, comparator, and optional analog store. The time-over-threshold (TOT) discriminator allows an all-digital interface to the array periphery readout while passing an analog measure of collected charge. Use of (existing) radiation hard processes, to build a detector bump-bonded to a pixel readout array, is targeted. Here, emphasis is on a qualitative explanation of how the unique circuit implementation benefits operation for Super Collider (SSC) detector application

A pixel unit-cell targeting 16ns resolution and radiation hardness in a column read-out particle vertex detector

International Nuclear Information System (INIS)

Wright, M.; Millaud, J.; Nygren, D.

1993-01-01

A pixel unit cell (PUC) circuit architecture, optimized for a column read out architecture, is reported. Each PUC contains an integrator, active filter, comparator, and optional analog store. The time-over-threshold (TOT) discriminator allows an all-digital interface to the array periphery readout while passing an analog measure of collected charge. Use of (existing) radiation hard processes, to build a detector bump-bonded to a pixel readout array, is targeted. Here emphasis is on a qualitative explanation of how the unique circuit implementation benefits operation for Super Collider (SSC) detector application. (orig.)

Macro Pixel ASIC (MPA): The readout ASIC for the pixel-strip (PS) module of the CMS outer tracker at HL-LHC

CERN Document Server

Ceresa, Davide; Kloukinas, Konstantinos; Jan Kaplon; Bialas, Wojciech; Re, Valerio; Traversi, Gianluca; Gaioni, Luigi; Ratti, Lodovico

2014-01-01

The CMS tracker at HL-LHC is required to provide prompt information on particles with high transverse momentum to the central Level\\,1 trigger. For this purpose, the innermost part of the outer tracker is based on a combination of a pixelated sensor with a short strip sensor, the so-called Pixel-Strip module (PS). The readout of these sensors is carried out by distinct ASICs, the Strip Sensor ASIC (SSA), for the strip layer, and the Macro Pixel ASIC (MPA) for the pixel layer. The processing of the data directly on the front-end module represents a design challenge due to the large data volume (30720\\,pixels and 1920\\,strips per module) and the limited power budget. This is the reason why several studies have been carried out to find the best compromise between ASICs performance and power consumption. This paper describes the current status of the MPA ASIC development where the logic for generating prompt information on particles with high transverse momentum is implemented. An overview of the readout method i...

Conception and modelling of photo-detection pixels. PIN photodiodes conceived in amorphous silicon for particles detection

International Nuclear Information System (INIS)

Negru, R.

2008-06-01

The research done has revealed that the a-Si:H is a material ideally suited for the detection of particles, while being resistant to radiation. It also has a low manufacturing cost, is compatible with existing technology and can be deposited over large areas. Thus, despite the low local mobility of charges (30 cm 2 /V/s), a-Si:H is a material of particular interest for manufacturing high-energy particle detection pixels. As a consequence of this, we have studied the feasibility of an experimental pixel stacked structure based on a-Si:H as a basic sensor element for an electromagnetic calorimeter. The structure of such a pixel consists of different components. First, a silicon PIN diode in a-Si:H is fabricated, followed by a bias resistor and a decoupling capacitor. Before such a structure is made and in order to optimize its design, it is essential to have an efficient behavioural model of the various components. Thus, our primary goal was to develop a two-dimensional physical model of the PIN diode using the SILVACO finite element calculation software. This a-Si:H PIN diode two-dimensional physical model allowed us to study the problem of crosstalk between pixels in a matrix structure of detectors. In particular, we concentrated on the leakage current and the current generated in the volume between neighbouring pixels. The successful implementation of this model in SPICE ensures its usefulness in other professional simulators and especially its integration into a complete electronic structure (PIN diode, bias resistor, decoupling capacity and low noise amplifier). Thanks to these modelling tools, we were able to simulate PIN diode structures in a-Si:H with different thicknesses and different dimensions. These simulations have allowed us to predict that the thicker structures are relevant to the design of the pixel detectors for high energy physics. Applications in astronomy, medical imaging and the analysis of the failure of silicon integrated circuits, can also

Prototype of the front-end circuit for the GOSSIP (Gas On Slimmed Silicon Pixel) chip in the 0.13 μm CMOS technology

CERN Document Server

Gromov, V; van der Graaf, H

2007-01-01

The new GOSSIP detector, capable to detect single electrons in gas, has certain advantages with respect silicon (pixel) detectors. It does not require a Si sensor; it has a very low detector parasitic capacitance and a zero bias current at the pixel input. These are attractive features to design a compact, low-noise and low-power integrated input circuit. A prototype of the integrated circuit has been developed in 0.13 μm CMOS technology. It includes a few channels equipped with preamplifier, discriminator and the digital circuit to study the feasibility of the TDC-perpixel concept. The design demonstrates very low input referred noise (60e- RMS) in combination with a fast peaking time (40 ns) and an analog power dissipation as low as 2 μW per channel. Switching activity on the clock bus (up to 100 MHz) in the close vicinity of the pixel input pads does not cause noticeable extra noise.

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...

A Low-Noise CMOS THz Imager Based on Source Modulation and an In-Pixel High-Q Passive Switched-Capacitor N-Path Filter

Science.gov (United States)

Boukhayma, Assim; Dupret, Antoine; Rostaing, Jean-Pierre; Enz, Christian

2016-01-01

This paper presents the first low noise complementary metal oxide semiconductor (CMOS) terahertz (THz) imager based on source modulation and in-pixel high-Q filtering. The 31×31 focal plane array has been fully integrated in a 0.13μm standard CMOS process. The sensitivity has been improved significantly by modulating the active THz source that lights the scene and performing on-chip high-Q filtering. Each pixel encompass a broadband bow tie antenna coupled to an N-type metal-oxide-semiconductor (NMOS) detector that shifts the THz radiation, a low noise adjustable gain amplifier and a high-Q filter centered at the modulation frequency. The filter is based on a passive switched-capacitor (SC) N-path filter combined with a continuous-time broad-band Gm-C filter. A simplified analysis that helps in designing and tuning the passive SC N-path filter is provided. The characterization of the readout chain shows that a Q factor of 100 has been achieved for the filter with a good matching between the analytical calculation and the measurement results. An input-referred noise of 0.2μV RMS has been measured. Characterization of the chip with different THz wavelengths confirms the broadband feature of the antenna and shows that this THz imager reaches a total noise equivalent power of 0.6 nW at 270 GHz and 0.8 nW at 600 GHz. PMID:26950131

A Low-Noise CMOS THz Imager Based on Source Modulation and an In-Pixel High-Q Passive Switched-Capacitor N-Path Filter.

Science.gov (United States)

Boukhayma, Assim; Dupret, Antoine; Rostaing, Jean-Pierre; Enz, Christian

2016-03-03

This paper presents the first low noise complementary metal oxide semiconductor (CMOS) deletedCMOS terahertz (THz) imager based on source modulation and in-pixel high-Q filtering. The 31 × 31 focal plane array has been fully integrated in a 0 . 13 μ m standard CMOS process. The sensitivity has been improved significantly by modulating the active THz source that lights the scene and performing on-chip high-Q filtering. Each pixel encompass a broadband bow tie antenna coupled to an N-type metal-oxide-semiconductor (NMOS) detector that shifts the THz radiation, a low noise adjustable gain amplifier and a high-Q filter centered at the modulation frequency. The filter is based on a passive switched-capacitor (SC) N-path filter combined with a continuous-time broad-band Gm-C filter. A simplified analysis that helps in designing and tuning the passive SC N-path filter is provided. The characterization of the readout chain shows that a Q factor of 100 has been achieved for the filter with a good matching between the analytical calculation and the measurement results. An input-referred noise of 0 . 2 μ V RMS has been measured. Characterization of the chip with different THz wavelengths confirms the broadband feature of the antenna and shows that this THz imager reaches a total noise equivalent power of 0 . 6 nW at 270 GHz and 0 . 8 nW at 600 GHz.

Monolithic active pixel sensor development for the upgrade of the ALICE inner tracking system

Science.gov (United States)

Aglieri, G.; Cavicchioli, C.; Chalmet, P. L.; Chanlek, N.; Collu, A.; Giubilato, P.; Hillemanns, H.; Junique, A.; Keil, M.; Kim, D.; Kim, J.; Kugathasan, T.; Lattuca, A.; Mager, M.; Marin Tobon, C. A.; Marras, D.; Martinengo, P.; Mattiazzo, S.; Mazza, G.; Mugnier, H.; Musa, L.; Pantano, D.; Puggioni, C.; Rousset, J.; Reidt, F.; Riedler, P.; Siddhanta, S.; Snoeys, W.; Usai, G.; van Hoorne, J. W.; Yang, P.; Yi, J.

2013-12-01

ALICE plans an upgrade of its Inner Tracking System for 2018. The development of a monolithic active pixel sensor for this upgrade is described. The TowerJazz 180 nm CMOS imaging sensor process has been chosen as it is possible to use full CMOS in the pixel due to the offering of a deep pwell and also to use different starting materials. The ALPIDE development is an alternative to approaches based on a rolling shutter architecture, and aims to reduce power consumption and integration time by an order of magnitude below the ALICE specifications, which would be quite beneficial in terms of material budget and background. The approach is based on an in-pixel binary front-end combined with a hit-driven architecture. Several prototypes have already been designed, submitted for fabrication and some of them tested with X-ray sources and particles in a beam. Analog power consumption has been limited by optimizing the Q/C of the sensor using Explorer chips. Promising but preliminary first results have also been obtained with a prototype ALPIDE. Radiation tolerance up to the ALICE requirements has also been verified.

Monolithic active pixel sensor development for the upgrade of the ALICE inner tracking system

International Nuclear Information System (INIS)

Aglieri, G; Cavicchioli, C; Hillemanns, H; Junique, A; Keil, M; Kugathasan, T; Mager, M; Tobon, C A Marin; Martinengo, P; Chalmet, P L; Mugnier, H; Chanlek, N; Collu, A; Marras, D; Giubilato, P; Mattiazzo, S; Kim, D; Kim, J; Lattuca, A; Mazza, G

2013-01-01

ALICE plans an upgrade of its Inner Tracking System for 2018. The development of a monolithic active pixel sensor for this upgrade is described. The TowerJazz 180 nm CMOS imaging sensor process has been chosen as it is possible to use full CMOS in the pixel due to the offering of a deep pwell and also to use different starting materials. The ALPIDE development is an alternative to approaches based on a rolling shutter architecture, and aims to reduce power consumption and integration time by an order of magnitude below the ALICE specifications, which would be quite beneficial in terms of material budget and background. The approach is based on an in-pixel binary front-end combined with a hit-driven architecture. Several prototypes have already been designed, submitted for fabrication and some of them tested with X-ray sources and particles in a beam. Analog power consumption has been limited by optimizing the Q/C of the sensor using Explorer chips. Promising but preliminary first results have also been obtained with a prototype ALPIDE. Radiation tolerance up to the ALICE requirements has also been verified

Development of ultra-light pixelated ladders for an ILC vertex detector

CERN Document Server

Chon-Sen, N.; Claus, G.; De Masi, R.; Deveaux, M.; Dulinski, W.; Goffe, M.; Goldstein, J.; Gregor, I.-M.; Hu-Guo, Ch.; Imhoff, M.; Muntz, C.; Nomerotski, A.; Santos, C.; Schrader, C.; Specht, M.; Stroth, J.; Winter, M.

2010-01-01

The development of ultra-light pixelated ladders is motivated by the requirements of the ILD vertex detector at ILC. This paper summarizes three projects related to system integration. The PLUME project tackles the issue of assembling double-sided ladders. The SERWIETE project deals with a more innovative concept and consists in making single-sided unsupported ladders embedded in an extra thin plastic enveloppe. AIDA, the last project, aims at building a framework reproducing the experimental running conditions where sets of ladders could be tested.

Conception and modelling of photo-detection pixels. PIN photodiodes conceived in amorphous silicon for particles detection; Conception et modelisation de pixels de photodetection: Photodiodes PIN en silicium amorphe en vue de leurs utilisations comme detecteurs de particules

Energy Technology Data Exchange (ETDEWEB)

Negru, R

2008-06-15

The research done has revealed that the a-Si:H is a material ideally suited for the detection of particles, while being resistant to radiation. It also has a low manufacturing cost, is compatible with existing technology and can be deposited over large areas. Thus, despite the low local mobility of charges (30 cm{sup 2}/V/s), a-Si:H is a material of particular interest for manufacturing high-energy particle detection pixels. As a consequence of this, we have studied the feasibility of an experimental pixel stacked structure based on a-Si:H as a basic sensor element for an electromagnetic calorimeter. The structure of such a pixel consists of different components. First, a silicon PIN diode in a-Si:H is fabricated, followed by a bias resistor and a decoupling capacitor. Before such a structure is made and in order to optimize its design, it is essential to have an efficient behavioural model of the various components. Thus, our primary goal was to develop a two-dimensional physical model of the PIN diode using the SILVACO finite element calculation software. This a-Si:H PIN diode two-dimensional physical model allowed us to study the problem of crosstalk between pixels in a matrix structure of detectors. In particular, we concentrated on the leakage current and the current generated in the volume between neighbouring pixels. The successful implementation of this model in SPICE ensures its usefulness in other professional simulators and especially its integration into a complete electronic structure (PIN diode, bias resistor, decoupling capacity and low noise amplifier). Thanks to these modelling tools, we were able to simulate PIN diode structures in a-Si:H with different thicknesses and different dimensions. These simulations have allowed us to predict that the thicker structures are relevant to the design of the pixel detectors for high energy physics. Applications in astronomy, medical imaging and the analysis of the failure of silicon integrated circuits, can

Design and development of pixel size calibration phantom for gamma camera

International Nuclear Information System (INIS)

Khokhar, S.B.; Manan, A.; Chaudary, M.A.; Pervaiz, T.

2005-01-01

The purpose of the study is to make pixel calibration phantom, to measure pixel size for different zoom factors and matrix sizes and to compare the pixel size with the values of provided by the vendor. For this purpose pixel size calibration phantom (rectangular in shape) made up of acrylic material having dimension 43 x 10 square cm was prepared. Seven circular holes at exact known distance with whole diameter 1.5 mm were born. High specific activity was filled in the holes of the phantom, acquired the image by fixing the number of counts at all available matrices and zoom factors. Pixel size was calculated by counting the number of pixels between focused points and divided the distance thereof by the number of pixels. Mean pixel size was calculated and compared it with reference value provided by the manufacturer of the camera. P- value was calculated which showed that most results lie in the acceptable limit. The calculated values agreed very well. However there exist some deviation at larger matrix sizes, which might be due to scattering of radiation that overlaps nearest pixels, and due to human error. (author)

Performance study of a MegaPixel single photon position sensitive photodetector EBCMOS

International Nuclear Information System (INIS)

Barbier, Remi; Baudot, J.; Chabanat, E.; Depasse, P.; Dulinski, W.; Estre, N.; Kaiser, C.T.; Laurent, N.; Winter, M.

2009-01-01

This development is related to the design and the integration of a Monolithic Active Pixel Sensor (MAPS) into a photosensitive proximity focusing vacuum-based tube. This EBCMOS project is dedicated to the fluorescent and the bioluminescent high speed imaging. The results of the full characterization of the first prototype are presented. Comparative tests with different fluorescent dyes have been performed in biology laboratories. Preliminary conclusions on the ability of EBCMOS to perform fast single-molecule tracking will be given.

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...

The Phase-2 ATLAS ITk Pixel Upgrade

CERN Document Server

Macchiolo, Anna; The ATLAS collaboration

2018-01-01

The new ATLAS ITk pixel system will be installed during the LHC Phase-II shutdown, to better take advantage of the increased luminosity of the HL-LHC. The detector will consist of 5 layers of stave-like support structures in the most central region and ring-shaped supports in the endcap regions, covering up to |η| < 4. While the outer 3 layers of the Pixel Detector are designed to operate for the full HL-LHC data taking period, the innermost 2 layers of the detector will be replaced around half of the lifetime. The ITk pixel detector will be instrumented with new sensors and readout electronics to provide improved tracking performance and radiation hardness compared to the current detector. Sensors will be read out by new ASICs based on the chip developed by the RD53 Collaboration. The pixel off-detector readout electronics will be implemented in the framework of the general ATLAS trigger and DAQ system with a readout speed of up to 5 Gb/s per data link for the innermost layers. Results of extensive tests...

CMS pixel upgrade project

CERN Document Server

Kaestli, Hans-Christian

2010-01-01

The LHC machine at CERN finished its first year of pp collisions at a center of mass energy of 7~TeV. While the commissioning to exploit its full potential is still ongoing, there are plans to upgrade its components to reach instantaneous luminosities beyond the initial design value after 2016. A corresponding upgrade of the innermost part of the CMS detector, the pixel detector, is needed. A full replacement of the pixel detector is planned in 2016. It will not only address limitations of the present system at higher data rates, but will aggressively lower the amount of material inside the fiducial tracking volume which will lead to better tracking and b-tagging performance. This article gives an overview of the project and illuminates the motivations and expected improvements in the detector performance.

CMS pixel upgrade project

CERN Document Server

INSPIRE-00575876

2011-01-01

The LHC machine at CERN finished its first year of pp collisions at a center of mass energy of 7 TeV. While the commissioning to exploit its full potential is still ongoing, there are plans to upgrade its components to reach instantaneous luminosities beyond the initial design value after 2016. A corresponding upgrade of the innermost part of the CMS detector, the pixel detector, is needed. A full replacement of the pixel detector is planned in 2016. It will not only address limitations of the present system at higher data rates, but will aggressively lower the amount of material inside the fiducial tracking volume which will lead to better tracking and b-tagging performance. This article gives an overview of the project and illuminates the motivations and expected improvements in the detector performance.

Production and integration of the ATLAS Insertable B-Layer

Science.gov (United States)

Abbott, B.; Albert, J.; Alberti, F.; Alex, M.; Alimonti, G.; Alkire, S.; Allport, P.; Altenheiner, S.; Ancu, L. S.; Anderssen, E.; Andreani, A.; Andreazza, A.; Axen, B.; Arguin, J.; Backhaus, M.; Balbi, G.; Ballansat, J.; Barbero, M.; Barbier, G.; Bassalat, A.; Bates, R.; Baudin, P.; Battaglia, M.; Beau, T.; Beccherle, R.; Bell, A.; Benoit, M.; Bermgan, A.; Bertsche, C.; Bertsche, D.; Bilbao de Mendizabal, J.; Bindi, F.; Bomben, M.; Borri, M.; Bortolin, C.; Bousson, N.; Boyd, R. G.; Breugnon, P.; Bruni, G.; Brossamer, J.; Bruschi, M.; Buchholz, P.; Budun, E.; Buttar, C.; Cadoux, F.; Calderini, G.; Caminada, L.; Capeans, M.; Carney, R.; Casse, G.; Catinaccio, A.; Cavalli-Sforza, M.; Červ, M.; Cervelli, A.; Chau, C. C.; Chauveau, J.; Chen, S. P.; Chu, M.; Ciapetti, M.; Cindro, V.; Citterio, M.; Clark, A.; Cobal, M.; Coelli, S.; Collot, J.; Crespo-Lopez, O.; Dalla Betta, G. F.; Daly, C.; D'Amen, G.; Dann, N.; Dao, V.; Darbo, G.; DaVia, C.; David, P.; Debieux, S.; Delebecque, P.; De Lorenzi, F.; de Oliveira, R.; Dette, K.; Dietsche, W.; Di Girolamo, B.; Dinu, N.; Dittus, F.; Diyakov, D.; Djama, F.; Dobos, D.; Dondero, P.; Doonan, K.; Dopke, J.; Dorholt, O.; Dube, S.; Dzahini, D.; Egorov, K.; Ehrmann, O.; Einsweiler, K.; Elles, S.; Elsing, M.; Eraud, L.; Ereditato, A.; Eyring, A.; Falchieri, D.; Falou, A.; Fausten, C.; Favareto, A.; Favre, Y.; Feigl, S.; Fernandez Perez, S.; Ferrere, D.; Fleury, J.; Flick, T.; Forshaw, D.; Fougeron, D.; Franconi, L.; Gabrielli, A.; Gaglione, R.; Gallrapp, C.; Gan, K. K.; Garcia-Sciveres, M.; Gariano, G.; Gastaldi, T.; Gavrilenko, I.; Gaudiello, A.; Geffroy, N.; Gemme, C.; Gensolen, F.; George, M.; Ghislain, P.; Giangiacomi, N.; Gibson, S.; Giordani, M. P.; Giugni, D.; Gjersdal, H.; Glitza, K. W.; Gnani, D.; Godlewski, J.; Gonella, L.; Gonzalez-Sevilla, S.; Gorelov, I.; Gorišek, A.; Gössling, C.; Grancagnolo, S.; Gray, H.; Gregor, I.; Grenier, P.; Grinstein, S.; Gris, A.; Gromov, V.; Grondin, D.; Grosse-Knetter, J.; Guescini, F.; Guido, E.; Gutierrez, P.; Hallewell, G.; Hartman, N.; Hauck, S.; Hasi, J.; Hasib, A.; Hegner, F.; Heidbrink, S.; Heim, T.; Heinemann, B.; Hemperek, T.; Hessey, N. P.; Hetmánek, M.; Hinman, R. R.; Hoeferkamp, M.; Holmes, T.; Hostachy, J.; Hsu, S. C.; Hügging, F.; Husi, C.; Iacobucci, G.; Ibragimov, I.; Idarraga, J.; Ikegami, Y.; Ince, T.; Ishmukhametov, R.; Izen, J. M.; Janoška, Z.; Janssen, J.; Jansen, L.; Jeanty, L.; Jensen, F.; Jentzsch, J.; Jezequel, S.; Joseph, J.; Kagan, H.; Kagan, M.; Karagounis, M.; Kass, R.; Kastanas, A.; Kenney, C.; Kersten, S.; Kind, P.; Klein, M.; Klingenberg, R.; Kluit, R.; Kocian, M.; Koffeman, E.; Korchak, O.; Korolkov, I.; Kostyukhina-Visoven, I.; Kovalenko, S.; Kretz, M.; Krieger, N.; Krüger, H.; Kruth, A.; Kugel, A.; Kuykendall, W.; La Rosa, A.; Lai, C.; Lantzsch, K.; Lapoire, C.; Laporte, D.; Lari, T.; Latorre, S.; Leyton, M.; Lindquist, B.; Looper, K.; Lopez, I.; Lounis, A.; Lu, Y.; Lubatti, H. J.; Maeland, S.; Maier, A.; Mallik, U.; Manca, F.; Mandelli, B.; Mandić, I.; Marchand, D.; Marchiori, G.; Marx, M.; Massol, N.; Mättig, P.; Mayer, J.; McGoldrick, G.; Mekkaoui, A.; Menouni, M.; Menu, J.; Meroni, C.; Mesa, J.; Michal, S.; Miglioranzi, S.; Mikuž, M.; Miucci, A.; Mochizuki, K.; Monti, M.; Moore, J.; Morettini, P.; Morley, A.; Moss, J.; Muenstermann, D.; Murray, P.; Nakamura, K.; Nellist, C.; Nelson, D.; Nessi, M.; Nisius, R.; Nordberg, M.; Nuiry, F.; Obermann, T.; Ockenfels, W.; Oide, H.; Oriunno, M.; Ould-Saada, F.; Padilla, C.; Pangaud, P.; Parker, S.; Pelleriti, G.; Pernegger, H.; Piacquadio, G.; Picazio, A.; Pohl, D.; Polini, A.; Pons, X.; Popule, J.; Portell Bueso, X.; Potamianos, K.; Povoli, M.; Puldon, D.; Pylypchenko, Y.; Quadt, A.; Quayle, B.; Rarbi, F.; Ragusa, F.; Rambure, T.; Richards, E.; Riegel, C.; Ristic, B.; Rivière, F.; Rizatdinova, F.; RØhne, O.; Rossi, C.; Rossi, L. P.; Rovani, A.; Rozanov, A.; Rubinskiy, I.; Rudolph, M. S.; Rummler, A.; Ruscino, E.; Sabatini, F.; Salek, D.; Salzburger, A.; Sandaker, H.; Sannino, M.; Sanny, B.; Scanlon, T.; Schipper, J.; Schmidt, U.; Schneider, B.; Schorlemmer, A.; Schroer, N.; Schwemling, P.; Sciuccati, A.; Seidel, S.; Seiden, A.; Šícho, P.; Skubic, P.; Sloboda, M.; Smith, D. S.; Smith, M.; Sood, A.; Spencer, E.; Stramaglia, M.; Strauss, M.; Stucci, S.; Stugu, B.; Stupak, J.; Styles, N.; Su, D.; Takubo, Y.; Tassan, J.; Teng, P.; Teixeira, A.; Terzo, S.; Therry, X.; Todorov, T.; Tomášek, M.; Toms, K.; Travaglini, R.; Trischuk, W.; Troncon, C.; Troska, G.; Tsiskaridze, S.; Tsurin, I.; Tsybychev, D.; Unno, Y.; Vacavant, L.; Verlaat, B.; Vigeolas, E.; Vogt, M.; Vrba, V.; Vuillermet, R.; Wagner, W.; Walkowiak, W.; Wang, R.; Watts, S.; Weber, M. S.; Weber, M.; Weingarten, J.; Welch, S.; Wenig, S.; Wensing, M.; Wermes, N.; Wittig, T.; Wittgen, M.; Yildizkaya, T.; Yang, Y.; Yao, W.; Yi, Y.; Zaman, A.; Zaidan, R.; Zeitnitz, C.; Ziolkowski, M.; Zivkovic, V.; Zoccoli, A.; Zwalinski, L.

2018-05-01

During the shutdown of the CERN Large Hadron Collider in 2013-2014, an additional pixel layer was installed between the existing Pixel detector of the ATLAS experiment and a new, smaller radius beam pipe. The motivation for this new pixel layer, the Insertable B-Layer (IBL), was to maintain or improve the robustness and performance of the ATLAS tracking system, given the higher instantaneous and integrated luminosities realised following the shutdown. Because of the extreme radiation and collision rate environment, several new radiation-tolerant sensor and electronic technologies were utilised for this layer. This paper reports on the IBL construction and integration prior to its operation in the ATLAS detector.

Realistic full wave modeling of focal plane array pixels.

Energy Technology Data Exchange (ETDEWEB)

Campione, Salvatore [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Electromagnetic Theory Dept.; Warne, Larry K. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Electromagnetic Theory Dept.; Jorgenson, Roy E. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Electromagnetic Theory Dept.; Davids, Paul [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Applied Photonic Microsystems Dept.; Peters, David W. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Applied Photonic Microsystems Dept.

2017-11-01

Here, we investigate full-wave simulations of realistic implementations of multifunctional nanoantenna enabled detectors (NEDs). We focus on a 2x2 pixelated array structure that supports two wavelengths of operation. We design each resonating structure independently using full-wave simulations with periodic boundary conditions mimicking the whole infinite array. We then construct a supercell made of a 2x2 pixelated array with periodic boundary conditions mimicking the full NED; in this case, however, each pixel comprises 10-20 antennas per side. In this way, the cross-talk between contiguous pixels is accounted for in our simulations. We observe that, even though there are finite extent effects, the pixels work as designed, each responding at the respective wavelength of operation. This allows us to stress that realistic simulations of multifunctional NEDs need to be performed to verify the design functionality by taking into account finite extent and cross-talk effects.

Development of thin sensors and a novel interconnection technology for the upgrade of the ATLAS pixel system

Energy Technology Data Exchange (ETDEWEB)

Beimforde, Michael

2010-07-19

To extend the discovery potential of the experiments at the LHC accelerator a two phase luminosity upgrade towards the super LHC (sLHC) with a maximum instantaneous luminosity of 10{sup 35}/cm{sup 2}s{sup 1} is planned. Retaining the reconstruction efficiency and spatial resolution of the ATLAS tracking detector at the sLHC, new pixel modules have to be developed that have a higher granularity, can be placed closer to the interaction point, and allow for a cost-efficient coverage of a larger pixel detector volume compared to the present one. The reduced distance to the interaction point calls for more compact modules that have to be radiation hard to supply a sufficient charge collection efficiency up to an integrated particle fluence equivalent to that of (1-2).10{sup 16} 1-MeV-neutrons per square centimeter (n{sub eq}/cm{sup 2}). Within this thesis a new module concept was partially realised and evaluated for the operation within an ATLAS pixel detector at the sLHC. This module concept utilizes a novel thin sensor production process for thin n-in-p silicon sensors which potentially allow for a higher radiation hardness at a reduced cost. Furthermore, the new 3D-integration technology ICV-SLID is explored which will allow for increasing the active area of the modules from 71% to about 90% and hence, for employing the modules in the innermost layer of the upgraded ATLAS pixel detector. A semiconductor simulation and measurements of irradiated test sensors are used to optimize the implantation parameters for the inter-pixel isolation of the thin sensors. These reduce the crosstalk between the pixel channels and should allow for operating the sensors during the whole runtime of the experiment without causing junction breakdowns. The characterization of the first production of sensors with active thicknesses of 75 {mu}m and 150 {mu}m proved that thin pixel sensors can be successfully produced with the new process technology. Thin pad sensors with a reduced inactive

Development of thin sensors and a novel interconnection technology for the upgrade of the ATLAS pixel system

International Nuclear Information System (INIS)

Beimforde, Michael

2010-01-01

To extend the discovery potential of the experiments at the LHC accelerator a two phase luminosity upgrade towards the super LHC (sLHC) with a maximum instantaneous luminosity of 10 35 /cm 2 s 1 is planned. Retaining the reconstruction efficiency and spatial resolution of the ATLAS tracking detector at the sLHC, new pixel modules have to be developed that have a higher granularity, can be placed closer to the interaction point, and allow for a cost-efficient coverage of a larger pixel detector volume compared to the present one. The reduced distance to the interaction point calls for more compact modules that have to be radiation hard to supply a sufficient charge collection efficiency up to an integrated particle fluence equivalent to that of (1-2).10 16 1-MeV-neutrons per square centimeter (n eq /cm 2 ). Within this thesis a new module concept was partially realised and evaluated for the operation within an ATLAS pixel detector at the sLHC. This module concept utilizes a novel thin sensor production process for thin n-in-p silicon sensors which potentially allow for a higher radiation hardness at a reduced cost. Furthermore, the new 3D-integration technology ICV-SLID is explored which will allow for increasing the active area of the modules from 71% to about 90% and hence, for employing the modules in the innermost layer of the upgraded ATLAS pixel detector. A semiconductor simulation and measurements of irradiated test sensors are used to optimize the implantation parameters for the inter-pixel isolation of the thin sensors. These reduce the crosstalk between the pixel channels and should allow for operating the sensors during the whole runtime of the experiment without causing junction breakdowns. The characterization of the first production of sensors with active thicknesses of 75 μm and 150 μm proved that thin pixel sensors can be successfully produced with the new process technology. Thin pad sensors with a reduced inactive edge demonstrate that the active

Gains of integrating sector-wise pollution regulation

DEFF Research Database (Denmark)

Jacobsen, Lars Bo; Nielsen, Max; Nielsen, Rasmus

2016-01-01

This paper extends the Orani-G Computable General Equilibrium model with an externality market. The externality market is modelled with a limited number of pollution permits that are traded between representative firms in different sectors. The model is applied to identify the gains of a common...... of introducing more coherent regulatory frameworks that include all polluters under the same regulatory system....

Pixel readout chips in deep submicron CMOS for ALICE and LHCb tolerant to 10 Mrad and beyond

International Nuclear Information System (INIS)

Snoeys, W.; Burns, M.; Campbell, M.; Cantatore, E.; Cencelli, V.; Dinapoli, R.; Heijne, E.; Jarron, P.; Lamanna, P.; Minervini, D.; Morel, M.; O'Shea, V.; Quiquempoix, V.; Bello, D.S.S.D.San Segundo; Van Koningsveld, B.; Wyllie, K.

2001-01-01

The ALICE1LHCB chip is a mixed-mode integrated circuit designed to read out silicon pixel detectors for two different applications: particle tracking in the ALICE Silicon Pixel Detector and particle identification in the LHCb Ring Imaging Cherenkov detector. To satisfy the different needs for these two experiments, the chip can be operated in two different modes. In tracking mode all the 50 μmx425 μm pixel cells in the 256x32 array are read out individually, whilst in particle identification mode they are combined in groups of 8 to form a 32x32 array of 400 μmx425 μm cells. Radiation tolerance was enhanced through special circuit layout. Sensitivity to coupling of digital signals into the analog front end was minimized. System issues such as testability and uniformity further constrained the design. The circuit is currently being manufactured in a commercial 0.25 μm CMOS technology

A 128 pixel linear array for radiotherapy quality assurance

Energy Technology Data Exchange (ETDEWEB)

Franco, L. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain); Gomez, F. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain)]. E-mail: faustgr@usc.es; Iglesias, A. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain); Lobato, R. [Hospital Clinico Universitario de Santiago, 15706 Santiago (Spain); Marin, J. [CIEMAT, Laboratorio de Electronica y Automatica, 28040 Madrid Spain (Spain); Mosquera, J. [Hospital Clinico Universitario de Santiago, 15706 Santiago (Spain); Pardo, J. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain)]. E-mail: juanpm@usc.es; Pazos, A. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain); Pena, J. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain); Pombar, M. [Hospital Clinico Universitario de Santiago, 15706 Santiago (Spain); Rodriguez, A. [Departmento de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, campus sur s/n, 15782 Santiago de Compostela (Spain); Saavedra, D. [Universidade da Coruna, Dpto. de Enxeneria Industrial II, 15403 Ferrol Spain (Spain); Sendon, J. [Hospital Clinico Universitario de Santiago, 15706 Santiago (Spain); Yanez, A. [Universidade da Coruna, Dpto. de Enxeneria Industrial II, 15403 Ferrol Spain (Spain)

2004-12-11

New radiotherapy techniques require detectors able to verify and monitor the clinical beam with high spatial resolution and fast response. Room temperature organic liquid ionization detectors are becoming an alternative to standard air ionization chambers, due to their tissue equivalent behavior, their sensibility and small directional dependence. A liquid isooctane filled ionization linear array for radiotherapy quality assurance has been designed, built and tested. The detector consists of 128 pixels, each of them with an area of 1.7mmx1.7mm and a gap of 0.5mm. The small pixel size makes the detector ideal for high gradient beam profiles like those present in Intensity Modulated Radiation Therapy. The gap and the polarization voltage have been chosen in order to guarantee a linear relationship between the dose rate and the readout signal at high dose rates. As readout electronics we use the X-ray Data Acquisition System with the Xchip developed by the CCLRC.In the first device tests we have confirmed linearity up to a 6.7Gy/min dose rate with a deviation less than 1%. A profile with a signal-to-noise ratio around 500 can be obtained for a 4Gy/min dose rate with a 10 ms integration time.

A 128 pixel linear array for radiotherapy quality assurance

International Nuclear Information System (INIS)

Franco, L.; Gomez, F.; Iglesias, A.; Lobato, R.; Marin, J.; Mosquera, J.; Pardo, J.; Pazos, A.; Pena, J.; Pombar, M.; Rodriguez, A.; Saavedra, D.; Sendon, J.; Yanez, A.

2004-01-01

New radiotherapy techniques require detectors able to verify and monitor the clinical beam with high spatial resolution and fast response. Room temperature organic liquid ionization detectors are becoming an alternative to standard air ionization chambers, due to their tissue equivalent behavior, their sensibility and small directional dependence. A liquid isooctane filled ionization linear array for radiotherapy quality assurance has been designed, built and tested. The detector consists of 128 pixels, each of them with an area of 1.7mmx1.7mm and a gap of 0.5mm. The small pixel size makes the detector ideal for high gradient beam profiles like those present in Intensity Modulated Radiation Therapy. The gap and the polarization voltage have been chosen in order to guarantee a linear relationship between the dose rate and the readout signal at high dose rates. As readout electronics we use the X-ray Data Acquisition System with the Xchip developed by the CCLRC.In the first device tests we have confirmed linearity up to a 6.7Gy/min dose rate with a deviation less than 1%. A profile with a signal-to-noise ratio around 500 can be obtained for a 4Gy/min dose rate with a 10 ms integration time

Study of plasma charging-induced white pixel defect increase in CMOS active pixel sensor

International Nuclear Information System (INIS)

Tokashiki, Ken; Bai, KeunHee; Baek, KyeHyun; Kim, Yongjin; Min, Gyungjin; Kang, Changjin; Cho, Hanku; Moon, Jootae

2007-01-01

Plasma process-induced 'white pixel defect' (WPD) of CMOS active pixel sensor (APS) is studied for Si3N4 spacer etch back process by using a magnetically enhanced reactive ion etching (MERIE) system. WPD preferably takes place at the wafer edge region when the magnetized plasma is applied to Si3N4 etch. Plasma charging analysis reveals that the plasma charge-up characteristic is well matching the edge-intensive WPD generation, rather than the UV radiation. Plasma charging on APS transfer gate might lead to a gate leakage, which could play a role in generation of signal noise or WPD. In this article the WPD generation mechanism will be discussed from plasma charging point of view

AGAPEROS Searches for microlensing in the LMC with the Pixel Method; 1, Data treatment and pixel light curves production

CERN Document Server

Melchior, A.-L.; Ansari, R.; Aubourg, E.; Baillon, P.; Bareyre, P.; Bauer, F.; Beaulieu, J.-Ph.; Bouquet, A.; Brehin, S.; Cavalier, F.; Char, S.; Couchot, F.; Coutures, C.; Ferlet, R.; Fernandez, J.; Gaucherel, C.; Giraud-Heraud, Y.; Glicenstein, J.-F.; Goldman, B.; Gondolo, P.; Gros, M.; Guibert, J.; Gry, C.; Hardin, D.; Kaplan, J.; de Kat, J.; Lachieze-Rey, M.; Laurent, B.; Lesquoy, E.; Magneville, Ch.; Mansoux, B.; Marquette, J.-B.; Maurice, E.; Milsztajn, A.; Moniez, M.; Moreau, O.; Moscoso, L.; Palanque-Delabrouille, N.; Perdereau, O.; Prevot, L.; Renault, C.; Queinnec, F.; Rich, J.; Spiro, M.; Vigroux, L.; Zylberajch, S.; Vidal-Madjar, A.; Magneville, Ch.

1999-01-01

The presence and abundance of MAssive Compact Halo Objects (MACHOs) towards the Large Magellanic Cloud (LMC) can be studied with microlensing searches. The 10 events detected by the EROS and MACHO groups suggest that objects with 0.5 Mo could fill 50% of the dark halo. This preferred mass is quite surprising, and increasing the presently small statistics is a crucial issue. Additional microlensing of stars too dim to be resolved in crowded fields should be detectable using the Pixel Method. We present here an application of this method to the EROS 91-92 data (one tenth of the whole existing data set). We emphasize the data treatment required for monitoring pixel fluxes. Geometric and photometric alignments are performed on each image. Seeing correction and error estimates are discussed. 3.6" x 3.6" super-pixel light curves, thus produced, are very stable over the 120 days time-span. Fluctuations at a level of 1.8% of the flux in blue and 1.3% in red are measured on the pixel light curves. This level of stabil...

Time-optimal control of nuclear reactor power with adaptive proportional- integral-feedforward gains

International Nuclear Information System (INIS)

Park, Moon Ghu; Cho, Nam Zin

1993-01-01

A time-optimal control method which consists of coarse and fine control stages is described here. During the coarse control stage, the maximum control effort (time-optimal) is used to direct the system toward the switching boundary which is set near the desired power level. At this boundary, the controller is switched to the fine control stage in which an adaptive proportional-integral-feedforward (PIF) controller is used to compensate for any unmodeled reactivity feedback effects. This fine control is also introduced to obtain a constructive method for determining the (adaptive) feedback gains against the sampling effect. The feedforward control term is included to suppress the over-or undershoot. The estimation and feedback of the temperature-induced reactivity is also discussed

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.

Human vision-based algorithm to hide defective pixels in LCDs

Science.gov (United States)

Kimpe, Tom; Coulier, Stefaan; Van Hoey, Gert

2006-02-01

Producing displays without pixel defects or repairing defective pixels is technically not possible at this moment. This paper presents a new approach to solve this problem: defects are made invisible for the user by using image processing algorithms based on characteristics of the human eye. The performance of this new algorithm has been evaluated using two different methods. First of all the theoretical response of the human eye was analyzed on a series of images and this before and after applying the defective pixel compensation algorithm. These results show that indeed it is possible to mask a defective pixel. A second method was to perform a psycho-visual test where users were asked whether or not a defective pixel could be perceived. The results of these user tests also confirm the value of the new algorithm. Our "defective pixel correction" algorithm can be implemented very efficiently and cost-effectively as pixel-dataprocessing algorithms inside the display in for instance an FPGA, a DSP or a microprocessor. The described techniques are also valid for both monochrome and color displays ranging from high-quality medical displays to consumer LCDTV applications.

Digital Architecture of the New ATLAS Pixel Chip FE-I4

CERN Document Server

"Barbero, M; The ATLAS collaboration

2009-01-01

With the high hit rate foreseen for the innermost layers at an upgraded LHC, the current ATLAS Front-End pixel chip FE-I3 would start being inefficient. The main source of inefficiency comes from the copying mechanism of the pixel hits from the pixel array to the end of column buffers. A new ATLAS pixel chip FE-I4 is being developed in a 130 nm technology for use both in the framework of the Insertable B-Layer (IBL) project and for the outer layers of Super-LHC. FE-I4 is 80×336 pixels wide and features a reduced pixel size of 50×250 μm2. In the current design, a new digital architecture is introduced in which hit memories are distributed across the entire chip and the pixels organized in regions. Additional features include neighbor hit checking which allows a timewalk-less hit recording.

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...

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

Low-power priority Address-Encoder and Reset-Decoder data-driven readout for Monolithic Active Pixel Sensors for tracker system

International Nuclear Information System (INIS)

Yang, P.; Aglieri, G.; Cavicchioli, C.; Chalmet, P.L.; Chanlek, N.; Collu, A.; Gao, C.; Hillemanns, H.; Junique, A.; Kofarago, M.; Keil, M.; Kugathasan, T.; Kim, D.; Kim, J.; Lattuca, A.; Marin Tobon, C.A.; Marras, D.; Mager, M.; Martinengo, P.; Mazza, G.

2015-01-01

Active Pixel Sensors used in High Energy Particle Physics require low power consumption to reduce the detector material budget, low integration time to reduce the possibilities of pile-up and fast readout to improve the detector data capability. To satisfy these requirements, a novel Address-Encoder and Reset-Decoder (AERD) asynchronous circuit for a fast readout of a pixel matrix has been developed. The AERD data-driven readout architecture operates the address encoding and reset decoding based on an arbitration tree, and allows us to readout only the hit pixels. Compared to the traditional readout structure of the rolling shutter scheme in Monolithic Active Pixel Sensors (MAPS), AERD can achieve a low readout time and a low power consumption especially for low hit occupancies. The readout is controlled at the chip periphery with a signal synchronous with the clock, allows a good digital and analogue signal separation in the matrix and a reduction of the power consumption. The AERD circuit has been implemented in the TowerJazz 180 nm CMOS Imaging Sensor (CIS) process with full complementary CMOS logic in the pixel. It works at 10 MHz with a matrix height of 15 mm. The energy consumed to read out one pixel is around 72 pJ. A scheme to boost the readout speed to 40 MHz is also discussed. The sensor chip equipped with AERD has been produced and characterised. Test results including electrical beam measurement are presented

Low-power priority Address-Encoder and Reset-Decoder data-driven readout for Monolithic Active Pixel Sensors for tracker system

Energy Technology Data Exchange (ETDEWEB)

Yang, P., E-mail: yangping0710@126.com [Central China Normal University, Wuhan (China); Aglieri, G.; Cavicchioli, C. [CERN, 1210 Geneva 23 (Switzerland); Chalmet, P.L. [MIND, Archamps (France); Chanlek, N. [Suranaree University of Technology, Nakhon Ratchasima (Thailand); Collu, A. [University of Cagliari, Cagliari (Italy); INFN (Italy); Gao, C. [Central China Normal University, Wuhan (China); Hillemanns, H.; Junique, A. [CERN, 1210 Geneva 23 (Switzerland); Kofarago, M. [CERN, 1210 Geneva 23 (Switzerland); University of Utrecht, Utrecht (Netherlands); Keil, M.; Kugathasan, T. [CERN, 1210 Geneva 23 (Switzerland); Kim, D. [Dongguk and Yonsei University, Seoul (Korea, Republic of); Kim, J. [Pusan National University, Busan (Korea, Republic of); Lattuca, A. [University of Torino, Torino (Italy); INFN (Italy); Marin Tobon, C.A. [CERN, 1210 Geneva 23 (Switzerland); Marras, D. [University of Cagliari, Cagliari (Italy); INFN (Italy); Mager, M.; Martinengo, P. [CERN, 1210 Geneva 23 (Switzerland); Mazza, G. [University of Torino, Torino (Italy); INFN (Italy); and others

2015-06-11

Active Pixel Sensors used in High Energy Particle Physics require low power consumption to reduce the detector material budget, low integration time to reduce the possibilities of pile-up and fast readout to improve the detector data capability. To satisfy these requirements, a novel Address-Encoder and Reset-Decoder (AERD) asynchronous circuit for a fast readout of a pixel matrix has been developed. The AERD data-driven readout architecture operates the address encoding and reset decoding based on an arbitration tree, and allows us to readout only the hit pixels. Compared to the traditional readout structure of the rolling shutter scheme in Monolithic Active Pixel Sensors (MAPS), AERD can achieve a low readout time and a low power consumption especially for low hit occupancies. The readout is controlled at the chip periphery with a signal synchronous with the clock, allows a good digital and analogue signal separation in the matrix and a reduction of the power consumption. The AERD circuit has been implemented in the TowerJazz 180 nm CMOS Imaging Sensor (CIS) process with full complementary CMOS logic in the pixel. It works at 10 MHz with a matrix height of 15 mm. The energy consumed to read out one pixel is around 72 pJ. A scheme to boost the readout speed to 40 MHz is also discussed. The sensor chip equipped with AERD has been produced and characterised. Test results including electrical beam measurement are presented.

Low-power priority Address-Encoder and Reset-Decoder data-driven readout for Monolithic Active Pixel Sensors for tracker system

Science.gov (United States)

Yang, P.; Aglieri, G.; Cavicchioli, C.; Chalmet, P. L.; Chanlek, N.; Collu, A.; Gao, C.; Hillemanns, H.; Junique, A.; Kofarago, M.; Keil, M.; Kugathasan, T.; Kim, D.; Kim, J.; Lattuca, A.; Marin Tobon, C. A.; Marras, D.; Mager, M.; Martinengo, P.; Mazza, G.; Mugnier, H.; Musa, L.; Puggioni, C.; Rousset, J.; Reidt, F.; Riedler, P.; Snoeys, W.; Siddhanta, S.; Usai, G.; van Hoorne, J. W.; Yi, J.

2015-06-01

Active Pixel Sensors used in High Energy Particle Physics require low power consumption to reduce the detector material budget, low integration time to reduce the possibilities of pile-up and fast readout to improve the detector data capability. To satisfy these requirements, a novel Address-Encoder and Reset-Decoder (AERD) asynchronous circuit for a fast readout of a pixel matrix has been developed. The AERD data-driven readout architecture operates the address encoding and reset decoding based on an arbitration tree, and allows us to readout only the hit pixels. Compared to the traditional readout structure of the rolling shutter scheme in Monolithic Active Pixel Sensors (MAPS), AERD can achieve a low readout time and a low power consumption especially for low hit occupancies. The readout is controlled at the chip periphery with a signal synchronous with the clock, allows a good digital and analogue signal separation in the matrix and a reduction of the power consumption. The AERD circuit has been implemented in the TowerJazz 180 nm CMOS Imaging Sensor (CIS) process with full complementary CMOS logic in the pixel. It works at 10 MHz with a matrix height of 15 mm. The energy consumed to read out one pixel is around 72 pJ. A scheme to boost the readout speed to 40 MHz is also discussed. The sensor chip equipped with AERD has been produced and characterised. Test results including electrical beam measurement are presented.

The Phase-2 ATLAS ITk Pixel Upgrade

CERN Document Server

Rossi, Leonardo Paolo; The ATLAS collaboration

2018-01-01

The upgrade of the ATLAS experiment for the operation at the High Luminosity Large Hadron Collider requires a new and more performant inner tracker, the ITk. The innermost part of this tracker will be built using silicon pixel detectors. This paper describes the ITk pixel project, which, after few years of design and test e ort, is now defined in detail.

Dense Iterative Contextual Pixel Classification using Kriging

DEFF Research Database (Denmark)

Ganz, Melanie; Loog, Marco; Brandt, Sami

2009-01-01

have been proposed to this end, e.g., iterative contextual pixel classification, iterated conditional modes, and other approaches related to Markov random fields. A problem of these methods, however, is their computational complexity, especially when dealing with high-resolution images in which......In medical applications, segmentation has become an ever more important task. One of the competitive schemes to perform such segmentation is by means of pixel classification. Simple pixel-based classification schemes can be improved by incorporating contextual label information. Various methods...... relatively long range interactions may play a role. We propose a new method based on Kriging that makes it possible to include such long range interactions, while keeping the computations manageable when dealing with large medical images....

Gossipo-3 A prototype of a Front-End Pixel Chip for Read-Out of Micro-Pattern Gas Detectors

CERN Document Server

Brezina, Christpoh; van der Graaf, Haryy; Gromov, Vladimir; Kluit, Ruud; Kruth, Andre; Zappon, Francesco

2009-01-01

In a joint effort of Nikhef (Amsterdam) and the University of Bonn, the Gossipo-3 integrated circuit (IC) has been developed. This circuit is a prototype of a chip dedicated for read-out of various types of position sensitive Micro-Pattern Gas detectors (MPGD). The Gossipo-3 is defined as a set of building blocks to be used in a future highly granulated (60 μm) chip. The pixel circuit can operate in two modes. In Time mode every readout pixel measures the hit arrival time and the charge deposit. For this purpose it has been equipped with a high resolution TDC (1.7 ns) covering dynamic range up to 102 μs. Charge collected by the pixel will be measured using Time-over- Threshold method in the range from 400 e- to 28000 e- with accuracy of 200 e- (standard deviation). In Counting mode every pixel operates as a 24-bit counter, counting the number of incoming hits. The circuit is also optimized to operate at low power consumption (100 mW/cm2) that is required to avoid the need for massive power transport and coo...

Performance of active edge pixel sensors

Science.gov (United States)

Bomben, M.; Ducourthial, A.; Bagolini, A.; Boscardin, M.; Bosisio, L.; Calderini, G.; D'Eramo, L.; Giacomini, G.; Marchiori, G.; Zorzi, N.; Rummler, A.; Weingarten, J.

2017-05-01

To cope with the High Luminosity LHC harsh conditions, the ATLAS inner tracker has to be upgraded to meet requirements in terms of radiation hardness, pile up and geometrical acceptance. The active edge technology allows to reduce the insensitive area at the border of the sensor thanks to an ion etched trench which avoids the crystal damage produced by the standard mechanical dicing process. Thin planar n-on-p pixel sensors with active edge have been designed and produced by LPNHE and FBK foundry. Two detector module prototypes, consisting of pixel sensors connected to FE-I4B readout chips, have been tested with beams at CERN and DESY. In this paper the performance of these modules are reported. In particular the lateral extension of the detection volume, beyond the pixel region, is investigated and the results show high hit efficiency also at the detector edge, even in presence of guard rings.

Cost and quality gains from diversification and vertical integration in the electricity industry: A DEA approach

International Nuclear Information System (INIS)

Arocena, Pablo

2008-01-01

This paper analyzes the degree of economies of vertical integration, diversification and scale in the electricity industry by means of Data Envelopment Analysis. We estimate the impact that alternative forms of unbundling would have on the cost and quality of supply, measured as the number and duration of supply interruptions, in a group of Spanish electric utilities. We find evidence of the existence of cost and quality gains from integrating power generation and distribution in the range of 1.1 to 4.9%, whereas diversifying the source of power generation saves between 1.3 and 4.3% of costs and quality. Finally, the scale efficiency of the largest utilities could be improved by dividing them into smaller units, provided that their current vertical scope and generation-mix are preserved. (author)

Cost and quality gains from diversification and vertical integration in the electricity industry: A DEA approach

Energy Technology Data Exchange (ETDEWEB)

Arocena, Pablo [Universidad Publica de Navarra, Dpto. Gestion de Empresas, Campus de Arrosadia, 31006 Pamplona (Spain)

2008-01-15

This paper analyzes the degree of economies of vertical integration, diversification and scale in the electricity industry by means of Data Envelopment Analysis. We estimate the impact that alternative forms of unbundling would have on the cost and quality of supply, measured as the number and duration of supply interruptions, in a group of Spanish electric utilities. We find evidence of the existence of cost and quality gains from integrating power generation and distribution in the range of 1.1 to 4.9%, whereas diversifying the source of power generation saves between 1.3 and 4.3% of costs and quality. Finally, the scale efficiency of the largest utilities could be improved by dividing them into smaller units, provided that their current vertical scope and generation-mix are preserved. (author)

An analytical method for PID controller tuning with specified gain and phase margins for integral plus time delay processes.

Science.gov (United States)

Hu, Wuhua; Xiao, Gaoxi; Li, Xiumin

2011-04-01

In this paper, an analytical method is proposed for proportional-integral/proportional-derivative/proportional-integral-derivative (PI/PD/PID) controller tuning with specified gain and phase margins (GPMs) for integral plus time delay (IPTD) processes. Explicit formulas are also obtained for estimating the GPMs resulting from given PI/PD/PID controllers. The proposed method indicates a general form of the PID parameters and unifies a large number of existing rules as PI/PD/PID controller tuning with various GPM specifications. The GPMs realized by existing PID tuning rules are computed and documented as a reference for control engineers to tune the PID controllers. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

Bio-Inspired Asynchronous Pixel Event Tricolor Vision Sensor.

Science.gov (United States)

Lenero-Bardallo, Juan Antonio; Bryn, D H; Hafliger, Philipp

2014-06-01

This article investigates the potential of the first ever prototype of a vision sensor that combines tricolor stacked photo diodes with the bio-inspired asynchronous pixel event communication protocol known as Address Event Representation (AER). The stacked photo diodes are implemented in a 22 × 22 pixel array in a standard STM 90 nm CMOS process. Dynamic range is larger than 60 dB and pixels fill factor is 28%. The pixels employ either simple pulse frequency modulation (PFM) or a Time-to-First-Spike (TFS) mode. A heuristic linear combination of the chip's inherent pseudo colors serves to approximate RGB color representation. Furthermore, the sensor outputs can be processed to represent the radiation in the near infrared (NIR) band without employing external filters, and to color-encode direction of motion due to an asymmetry in the update rates of the different diode layers.

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

The 150 ns detector project: Prototype preamplifier results

Science.gov (United States)

Warburton, W. K.; Russell, S. R.; Kleinfelder, Stuart A.

1994-08-01

The long-term goal of the 150 ns detector project is to develop a pixel area detector capable of 6 MHz frame rates (150 ns/frame). Our milestones toward this goal are: a single pixel, 1×256 1D and 8×8 2D detectors, 256×256 2D detectors and, finally, 1024 × 1024 2D detectors. The design strategy is to supply a complete electronics chain (resetting preamp, selectable gain amplifier, analog-to-digital converter (ADC), and memory) for each pixel. In the final detectors these will all be custom integrated circuits. The front-end preamplifiers are integrated first, since their design and performance are the most unusual and also critical to the project's success. Similarly, our early work is concentrated on devising and perfecting detector structures. In this paper we demonstrate the performance of prototypes of our integrated preamplifiers. While the final design will have 64 preamps to a chip, including a switchable gain stage, the prototypes were integrated 8 channels to a "Tiny Chip" and tested in 4 configurations (feedback capacitor Cf equal 2.5 or 4.0 pF, output directly or through a source follower). These devices have been tested thoroughly for reset settling times, gain, linearity, and electronic noise. They generally work as designed, being fast enough to easily integrate detector charge, settle, and reset in 150 ns. Gain and linearity appear to be acceptable. Current values of electronic noise, in double-sampling mode, are about twice the design goal of {2}/{3} of a single photon at 6 keV. We expect this figure to improve with the addition of the onboard amplifier stage and improved packaging. Our next test chip will include these improvements and allow testing with our first detector samples, which will be 1×256 (50 μm wide pixels) and 8×8 (1 mm 2 pixels) element detector on 1 mm thick silicon.

Prototypes for components of a control system for the ATLAS pixel detector at the HL-LHC

International Nuclear Information System (INIS)

Püllen, Lukas; Boek, Jennifer; Kersten, Susanne; Kind, Peter; Mättig, Peter; Zeitnitz, Christian

2013-01-01

In the years around 2020 an upgrade of the LHC to the HL-LHC is scheduled, which will increase the accelerator's instantaneous luminosity by a factor of 5 and the integrated luminosity by a factor of 10. In the context of this upgrade, the inner detector (including the pixel detector) of the ATLAS experiment will be replaced. This new pixel detector requires a specific control system which complies with strict requirements in terms of radiation hardness, material budget and space for the electronics in the ATLAS experiment. The University of Wuppertal is developing a concept for a DCS (Detector Control System) network consisting of two kinds of ASICs. The first ASIC is the DCS chip which is located on the pixel detector, very close to the interaction point. The second ASIC is the DCS Controller which is controlling 4×4 DCS chips from the outer regions of ATLAS via differential data lines. Both ASICs are manufactured in 130 nm deep sub-micron technology. We present results from reliability measurements under irradiation from new prototypes of components for the DCS network.

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.

Centi-pixel accurate real-time inverse distortion correction

CSIR Research Space (South Africa)

De Villiers, Johan P

2008-11-01

Full Text Available Inverse distortion is used to create an undistorted image from a distorted image. For each pixel in the undistorted image it is required to determine which pixel in the distorted image should be used. However the process of characterizing a lens...

PIXEL ANALYSIS OF PHOTOSPHERIC SPECTRAL DATA. I. PLASMA DYNAMICS

Energy Technology Data Exchange (ETDEWEB)

Rasca, Anthony P.; Chen, James [Plasma Physics Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Pevtsov, Alexei A., E-mail: anthony.rasca.ctr@nrl.navy.mil [National Solar Observatory, Sunspot, NM 88349 (United States)

2016-11-20

Recent observations of the photosphere using high spatial and temporal resolution show small dynamic features at or below the current resolving limits. A new pixel dynamics method has been developed to analyze spectral profiles and quantify changes in line displacement, width, asymmetry, and peakedness of photospheric absorption lines. The algorithm evaluates variations of line profile properties in each pixel and determines the statistics of such fluctuations averaged over all pixels in a given region. The method has been used to derive statistical characteristics of pixel fluctuations in observed quiet-Sun regions, an active region with no eruption, and an active region with an ongoing eruption. Using Stokes I images from the Vector Spectromagnetograph (VSM) of the Synoptic Optical Long-term Investigations of the Sun (SOLIS) telescope on 2012 March 13, variations in line width and peakedness of Fe i 6301.5 Å are shown to have a distinct spatial and temporal relationship with an M7.9 X-ray flare in NOAA 11429. This relationship is observed as stationary and contiguous patches of pixels adjacent to a sunspot exhibiting intense flattening in the line profile and line-center displacement as the X-ray flare approaches peak intensity, which is not present in area scans of the non-eruptive active region. The analysis of pixel dynamics allows one to extract quantitative information on differences in plasma dynamics on sub-pixel scales in these photospheric regions. The analysis can be extended to include the Stokes parameters and study signatures of vector components of magnetic fields and coupled plasma properties.

Monolithic pixels on moderate resistivity substrate and sparsifying readout architecture

International Nuclear Information System (INIS)

Giubilato, P.; Battaglia, M.; Bisello, D.; Caselle, M.; Chalmet, P.; Demaria, L.; Ikemoto, Y.; Kloukinas, K.; Mansuy, S.C.; Mattiazzo, S.; Marchioro, A.; Mugnier, H.; Pantano, D.; Potenza, A.; Rivetti, A.; Rousset, J.; Silvestrin, L.; Snoeys, W.

2013-01-01

The LePix projects aim realizing a new generation monolithic pixel detectors with improved performances at lesser cost with respect to both current state of the art monolithic and hybrid pixel sensors. The detector is built in a 90 nm CMOS process on a substrate of moderate resistivity. This allows charge collection by drift while maintaining the other advantages usually offered by MAPS, like having a single piece detector and using a standard CMOS production line. The collection by drift mechanism, coupled to the low capacitance design of the collecting node made possible by the monolithic approach, provides an excellent signal to noise ratio straight at the pixel cell together with a radiation tolerance far superior to conventional un-depleted MAPS. The excellent signal-to-noise performance is demonstrated by the device ability to separate the 6 keV 55 Fe double peak at room temperature. To achieve high granularity (10–20 µm pitch pixels) over large detector areas maintaining high readout speed, a completely new compressing architecture has been devised. This architecture departs from the mainstream hybrid pixel sparsification approach, which uses in-pixel logic to reduce data, by using topological compression to minimize pixel area and power consumption

CMOS Active Pixel Sensor Technology and Reliability Characterization Methodology

Science.gov (United States)

Chen, Yuan; Guertin, Steven M.; Pain, Bedabrata; Kayaii, Sammy

2006-01-01

This paper describes the technology, design features and reliability characterization methodology of a CMOS Active Pixel Sensor. Both overall chip reliability and pixel reliability are projected for the imagers.

Lagrange constraint neural networks for massive pixel parallel image demixing

Science.gov (United States)

Szu, Harold H.; Hsu, Charles C.

2002-03-01

We have shown that the remote sensing optical imaging to achieve detailed sub-pixel decomposition is a unique application of blind source separation (BSS) that is truly linear of far away weak signal, instantaneous speed of light without delay, and along the line of sight without multiple paths. In early papers, we have presented a direct application of statistical mechanical de-mixing method called Lagrange Constraint Neural Network (LCNN). While the BSAO algorithm (using a posteriori MaxEnt ANN and neighborhood pixel average) is not acceptable for remote sensing, a mirror symmetric LCNN approach is all right assuming a priori MaxEnt for unknown sources to be averaged over the source statistics (not neighborhood pixel data) in a pixel-by-pixel independent fashion. LCNN reduces the computation complexity, save a great number of memory devices, and cut the cost of implementation. The Landsat system is designed to measure the radiation to deduce surface conditions and materials. For any given material, the amount of emitted and reflected radiation varies by the wavelength. In practice, a single pixel of a Landsat image has seven channels receiving 0.1 to 12 microns of radiation from the ground within a 20x20 meter footprint containing a variety of radiation materials. A-priori LCNN algorithm provides the spatial-temporal variation of mixture that is hardly de-mixable by other a-posteriori BSS or ICA methods. We have already compared the Landsat remote sensing using both methods in WCCI 2002 Hawaii. Unfortunately the absolute benchmark is not possible because of lacking of the ground truth. We will arbitrarily mix two incoherent sampled images as the ground truth. However, the constant total probability of co-located sources within the pixel footprint is necessary for the remote sensing constraint (since on a clear day the total reflecting energy is constant in neighborhood receiving pixel sensors), we have to normalized two image pixel-by-pixel as well. Then, the

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)

Development of the ATLAS FE-I4 pixel readout IC for b-layer Upgrade and Super-LHC

CERN Document Server

Karagounis, M

2008-01-01

Motivated by the upcoming upgrade of the ATLAS hybrid pixel detector, a new Front-End (FE) IC is being developed in a 130nm technology to face the tightened requirements of the upgraded pixel system. The main design goals are the reduction of material and a decrease in power consumption combined with the capability to handle the higher hit rates that will result from the upgraded machine. New technology features like the higher integration density for digital circuits, better radiation tolerance and Triple-Well transistors are used for optimization and the implementation of new concepts. A description of the ongoing design work is given, focusing more on the analog part and peripheral design blocks.

The effect of split pixel HDR image sensor technology on MTF measurements

Science.gov (United States)

Deegan, Brian M.

2014-03-01

Split-pixel HDR sensor technology is particularly advantageous in automotive applications, because the images are captured simultaneously rather than sequentially, thereby reducing motion blur. However, split pixel technology introduces artifacts in MTF measurement. To achieve a HDR image, raw images are captured from both large and small sub-pixels, and combined to make the HDR output. In some cases, a large sub-pixel is used for long exposure captures, and a small sub-pixel for short exposures, to extend the dynamic range. The relative size of the photosensitive area of the pixel (fill factor) plays a very significant role in the output MTF measurement. Given an identical scene, the MTF will be significantly different, depending on whether you use the large or small sub-pixels i.e. a smaller fill factor (e.g. in the short exposure sub-pixel) will result in higher MTF scores, but significantly greater aliasing. Simulations of split-pixel sensors revealed that, when raw images from both sub-pixels are combined, there is a significant difference in rising edge (i.e. black-to-white transition) and falling edge (white-to-black) reproduction. Experimental results showed a difference of ~50% in measured MTF50 between the falling and rising edges of a slanted edge test chart.

Coherence and interlimb force control: Effects of visual gain.

Science.gov (United States)

Kang, Nyeonju; Cauraugh, James H

2018-03-06

Neural coupling across hemispheres and homologous muscles often appears during bimanual motor control. Force coupling in a specific frequency domain may indicate specific bimanual force coordination patterns. This study investigated coherence on pairs of bimanual isometric index finger force while manipulating visual gain and task asymmetry conditions. We used two visual gain conditions (low and high gain = 8 and 512 pixels/N), and created task asymmetry by manipulating coefficient ratios imposed on the left and right index finger forces (0.4:1.6; 1:1; 1.6:0.4, respectively). Unequal coefficient ratios required different contributions from each hand to the bimanual force task resulting in force asymmetry. Fourteen healthy young adults performed bimanual isometric force control at 20% of their maximal level of the summed force of both fingers. We quantified peak coherence and relative phase angle between hands at 0-4, 4-8, and 8-12 Hz, and estimated a signal-to-noise ratio of bimanual forces. The findings revealed higher peak coherence and relative phase angle at 0-4 Hz than at 4-8 and 8-12 Hz for both visual gain conditions. Further, peak coherence and relative phase angle values at 0-4 Hz were larger at the high gain than at the low gain. At the high gain, higher peak coherence at 0-4 Hz collapsed across task asymmetry conditions significantly predicted greater signal-to-noise ratio. These findings indicate that a greater level of visual information facilitates bimanual force coupling at a specific frequency range related to sensorimotor processing. Copyright © 2018 Elsevier B.V. All rights reserved.

Development of N+ in P pixel sensors for a high-luminosity large hadron collider

International Nuclear Information System (INIS)

Kamada, Shintaro; Yamamura, Kazuhisa; Unno, Yoshinobu; Ikegami, Yoichi

2014-01-01

Hamamatsu Photonics K. K. is developing an N+ in a p planar pixel sensor with high radiation tolerance for the high-luminosity large hadron collider (HL-LHC). The N+ in the p planar pixel sensor is a candidate for the HL-LHC and offers the advantages of high radiation tolerance at a reasonable price compared with the N+ in an n planar sensor, the three-dimensional sensor, and the diamond sensor. However, the N+ in the p planar pixel sensor still presents some problems that need to be solved, such as its slim edge and the danger of sparks between the sensor and readout integrated circuit. We are now attempting to solve these problems with wafer-level processes, which is important for mass production. To date, we have obtained a 250-μm edge with an applied bias voltage of 1000 V. To protect against high-voltage sparks from the edge, we suggest some possible designs for the N+ edge. - Highlights: • We achieved a tolerance of 1000 V with a 250-μm edge by Al2O3 side wall passivation. • Above is a wafer process and suitable for mass production. • For edge-spark protection, we suggest N+ edge with an isolation

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.

Pixel-based meshfree modelling of skeletal muscles

OpenAIRE