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Sample records for buried oxide silicon-on-insulator

  1. Total dose radiation response of modified commercial silicon-on-insulator materials with nitrogen implanted buried oxide

    Institute of Scientific and Technical Information of China (English)

    Zheng Zhong-Shan; Liu Zhong-Li; Yu Fang; Li Ning

    2012-01-01

    Nitrogen ions of various doses are implanted into the buried oxide (BOX) of commercial silicon-on-insulator (SOI)materials,and subsequent annealings are carried out at various temperatures.The total dose radiation responses of the nitrogen-implanted SOI wafers are characterized by the high frequency capacitance-voltage (C-V) technique after irradiation using a Co-60 source.It is found that there exist relatively complex relationships between the radiation hardness of the nitrogen implanted BOX and the nitrogen implantation dose at different irradiation doses.Fhe experimental results also suggest that a lower dose nitrogen implantation and a higher post-implantation annealing temperature are suitable for improving the radiation hardness of SOI wafer.Based on the measured C-V data,secondary ion mass spectrometry (SIMS),and Fourier transform infrared (FTIR) spectroscopy,the total dose responses of the nitrogen-implanted SOI wafers are discussed.

  2. A review of the mechanical stressors efficiency applied to the ultra-thin body & buried oxide fully depleted silicon on insulator technology

    Science.gov (United States)

    Morin, Pierre; Maitrejean, Sylvain; Allibert, Frederic; Augendre, Emmanuel; Liu, Qing; Loubet, Nicolas; Grenouillet, Laurent; Pofelski, Alexandre; Chen, Kangguo; Khakifirooz, Ali; Wacquez, Romain; Reboh, Shay; Bonnevialle, Aurore; le Royer, Cyrille; Morand, Yves; Kanyandekwe, Joel; Chanemougamme, Daniel; Mignot, Yann; Escarabajal, Yann; Lherron, Benoit; Chafik, Fadoua; Pilorget, Sonia; Caubet, Pierre; Vinet, Maud; Clement, Laurent; Desalvo, Barbara; Doris, Bruce; Kleemeier, Walter

    2016-03-01

    This paper reviews the different stressor techniques used in microelectronics, in the scope of the Ultra-Thin Body & Buried Oxide Fully-Depleted Silicon On Insulator technology (UTBB FD-SOI). We compare the mechanical efficiency of the various stressors and present the impact of device dimensions (active area, gate length and pitch) on their efficiency. Our study emphasizes the high efficiency, for the FD-SOI technology, of the intrinsically strained channels, compared to the traditional embedded raised source/drain and contact-etch stop liner. With these techniques FD-SOI technology has already demonstrated channel stress higher than 1.5 GPa for n type transistor and -2.3 GPa for the p type devices and we envision channel stress values up to ±3 GPa for n and p transistor channel, respectively. This performance is partly due to the mechanical configuration of intrinsically strained channels, in parallel mode rather than in serial mode as for the previous generation of stressors, which makes them less sensitive to the scaling of the contacted gate pitch. We also highlight another key element the high mechanical stability of the UTBB technology, related to the limited channel thickness (around 6 nm) which enables achieving highly stressed channel without substantial adaptation of the integration flows.

  3. Correlation between Co-60 and X-ray exposures on radiation-induced charge buildup in silicon-on-insulator buried oxides

    International Nuclear Information System (INIS)

    Large differences in charge buildup in SOI buried oxides can result between x-ray and Co-60 irradiations. The effects of bias configuration and substrate type on charge buildup and hardness assurance issues are explored

  4. Study of silicon-on-insulator substrates incorporated with buried MoSi2 layer

    International Nuclear Information System (INIS)

    Silicon-on-Insulator (SOI) substrates incorporated with buried MoSi2 were fabricated using room temperature plasma bonding technology and smart cut technology. The molybdenum disilicide phase formation and morphology were studied by means of four-point probe measurements, X-ray diffraction analysis, atomic force microscopy and transmission electron microscopy examination. It is found that the transition of high-resistance phase Mo3Si to low-resistance phase h-MoSi2 occurs at approximately 750 deg. C . The t-MoSi2 phase emerges at approximately 900 deg. C . SOI substrate incorporated with buried silicide layer of complete t-MoSi2 phase can be achieved by 900 deg. C annealing for 20 min

  5. Improvement on the breakdown voltage for silicon-on-insulator devices based on epitaxy-separation by implantation oxygen by a partial buried n+-layer

    Institute of Scientific and Technical Information of China (English)

    Hu Sheng-Dong; Wu Li-Juan; Zhou Jian-Lin; Gan Ping; Zhang Bo; Li Zhao-Ji

    2012-01-01

    A novel silicon-on-insulator (SOI) high-voltage device based on epitaxy-separation by implantation oxygen (SIMOX) with a partial buried n+-layer silicon-on-insulator (PBN SOI) is proposed in this paper. Based on the proposed expressions of the vertical interface electric field,the high concentration interface charges which are accumulated on the interface between top silicon layer and buried oxide layer (BOX) effectively enhance the electric field of the BOX (EI),resulting in a high breakdown voltage (BV) for the device.For the same thicknesses of top silicon layer (10 μ-n) and BOX (0.375 μm),the EI and BV of PBN SOI are improved by 186.5% and 45.4% in comparison with those of the conventional SOI,respectively.

  6. Influence of high-dose nitrogen implantation on the positive charge density of the buried oxide of silicon-on-insulator wafers%高剂量注氮对注氧隔离硅材料埋氧层中正电荷密度的影响

    Institute of Scientific and Technical Information of China (English)

    唐海马; 郑中山; 张恩霞; 于芳; 李宁; 王宁娟; 李国花; 马红芝

    2011-01-01

    The influence of nitrogen implantation on the properties of silicon-on-insulator buried oxide using separation by oxygen implantation was studied. Nitrogen ions were implanted into the buried oxide layer with a high-dose of 1016 cm-2.The experimental results showed that the positive charge density of the nitrogen-implanted buried oxide was obviously increased, compared with the control sampes without nitrogen implantation. It was also found that the post-implantation annealing caused an additional increase of the positive charge density in the nitrogen implanted samples. However,annealing time displayed a small effect on the positive charge density of the nitrogen implanted buried oxide, compared with the significant increase induced by nitrogen implantation. Moreover, the capacitance-voltage results showed that the positive charge density of the unannealed sample with nitrogen implanted is approximately equal to that of the sample annealed at 1100 ℃ for 2. 5 h in N2 ambient, despite an additional increase brought with annealing, and the buried oxide of the sample after 0.5 h annealing has a maximum value of positive charge density. According to the simulating results,the nitrogen implantation resulted in a heavy damage to the buried oxide, a lot of silicon and oxygen vacancies were introduced in the buried oxide during implantation. However, the Fourier transform infrared spectroscopy of the samples indicates that implantation induced defects can be basically eliminated after an annealing at 1100 ℃ for 0. 5 h. The increase of the positive charge density of the nitrogen implanted buried oxide is ascribed to the accumulation of implanted nitrogen near the interface of buried oxide and silicon, which caused the break of weak Si - Si bonds and the production of positive silicon ions in the silicon-rich region of the buried oxide near the interface, and this conclusion is supported by the results of secondary ion mass spectrometry.%为研究注氮改性对注氧

  7. Evolution of end-of-range defects in silicon-on-insulator substrates

    Energy Technology Data Exchange (ETDEWEB)

    Fazzini, P.F. [CEMES/CNRS, University of Toulouse, 29 Rue Jeanne Marvig, 31055 Toulouse Cedex 4 (France); LAAS/CNRS, University of Toulouse, 7 Avenue du Colonel Roche, 31077 Toulouse Cedex 4 (France)], E-mail: pffazzin@laas.fr; Cristiano, F. [LAAS/CNRS, University of Toulouse, 7 Avenue du Colonel Roche, 31077 Toulouse Cedex 4 (France); Dupre, C. [CEA-LETI, Minatec 17 Avenue des Martyrs, 38054 Grenoble Cedex 9 (France); IMEP Minatec- 3 parvis Louis Neel, 38 016 Grenoble Cedex 1 (France); Paul, S. [Mattson Thermal Products GmbH, Daimlerstr. 10, D-89160 Dornstadt (Germany); Ernst, T. [CEA-LETI, Minatec 17 Avenue des Martyrs, 38054 Grenoble Cedex 9 (France); Kheyrandish, H. [CSMA-MATS, Stoke-on-Trent, Staffordshire ST4 7LQ (United Kingdom); Bourdelle, K.K. [SOITEC, Parc Technologique des Fontaines, Bernin 38926, Crolles Cedex (France); Lerch, W. [Mattson Thermal Products GmbH, Daimlerstr. 10, D-89160 Dornstadt (Germany)

    2008-12-05

    The detailed knowledge of the effects of the buried interface on defect evolution in silicon-on-insulator wafers is mandatory to accurately control dopant diffusion and activation. To be able to study this phenomenon, quantitative data on end-of-range defect evolution must be obtained taking into account the several possible effects of the buried interface. In this work we report some transmission electron microscopy data acquired to study the effect of the Si top layer/buried oxide interface acting as an interstitial sink in silicon-on-insulator wafers. It is shown that this effect can explain the obtained data and that our results are compatible with a non-conservative Ostwald ripening mechanism describing defect evolution in silicon-on-insulator structures.

  8. Analysis of the breakdown mechanism for an ultra high voltage high-side thin layer silicon-on-insulator p-channel low-density metal-oxide semiconductor

    Institute of Scientific and Technical Information of China (English)

    Zhuang Xiang; Qiao Ming; Zhang Bo; Li Zhao-Ji

    2012-01-01

    This paper discusses the breakdown mechanism and proposes a new simulation and test method of breakdown voltage (BV) for an ultra-high-voltage (UHV) high-side thin layer silicon-on-insulator (SOI) p-channel low-density metaloxide semiconductor (LDMOS).Compared with the conventional simulation method,the new one is more accordant with the actual conditions of a device that can be used in the high voltage circuit.The BV of the SOI p-channel LDMOS can be properly represented and the effect of reduced bulk field can be revealed by employing the new simulation method.Simulation results show that the off-state (on-state) BV of the SOI p-channel LDMOS can reach 741 (620) V in the 3-μm-thick buried oxide layer,50-un-length drift region,and at -400 V back-gate voltage,enabling the device to be used in a 400 V UHV integrated circuit.

  9. Modulation of flat-band voltage on H-terminated silicon-on-insulator pseudo-metal-oxide-semiconductor field effect transistors by adsorption and reaction events

    Science.gov (United States)

    Dubey, Girjesh; Rosei, Federico; Lopinski, Gregory P.

    2011-05-01

    Accumulation mode pseudo-MOSFETs formed on hydrogen terminated silicon-on-insulator (SOI-H) were used to probe molecular adsorption and reaction events. Current-voltage characteristics of such n-channel devices are found to be sensitive to the environment, with the accumulation threshold voltage, or flat-band voltage, exhibiting large reversible changes upon cycling between ambient atmosphere, high vacuum (water and pyridine vapor at pressures in the Torr range. The field-effect mobility is found to be comparatively less affected through these transitions. Oxidation of the H-terminated surface in ambient conditions leads to irreversible shifts in both the flat-band voltage and the field-effect mobility. A photochemical gas phase reaction with decene is used to form a decyl monolayer on the SOI(100)-H surface. Formation of this monolayer is found to result in a relatively small shift of the threshold voltage and only a slight degradation of the field effect mobility, suggesting that alkyl monolayer dielectrics formed in this way could function as good passivating dielectrics in field effect sensing applications.

  10. Effects of Techniques of Implanting Nitrogen into Buried Oxide on the Characteristics of Partially Depleted SOI PMOSFET

    Institute of Scientific and Technical Information of China (English)

    ZHENG Zhong-Shan; LIU Zhong-Li; ZHANG Guo-Qiang; LI Ning; FAN Kai; ZHANG En-Xia; YI Wan-Bing; CHEN Meng; WANG Xi

    2005-01-01

    @@ Effects of techniques of implanting nitrogen into buried oxide on the characteristics of the partially depleted silicon-on-insulator (SOI) p-channel metal-oxide-semiconductor field-effect transistors (PMOSFETs) have beenstudied with three different nitrogen implantation doses, 8 × 1015, 2 × 1016, and 1 × 1017 cm-2.

  11. A Partial-Ground-Plane (PGP) Silicon-on-Insulator (SOI) Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) for Deep Sub-0.1-μm Channel Regime

    Science.gov (United States)

    Yanagi, Shin-ichiro; Nakakubo, Atsushi; Omura, Yasuhisa

    2001-04-01

    Silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistor (MOSFET) offers a number of advantages over conventional bulk silicon transistors. In this paper, we present a new SOI device structure called a “partial-ground-plane” SOI MOSFET down to 50 nm channel length. This new device shows good suppression of short-channel effect together with a small subthreshold swing and has a good driveability with a low leakage current.

  12. Ultra-Low Power High Temperature and Radiation Hard Complementary Metal-Oxide-Semiconductor (CMOS Silicon-on-Insulator (SOI Voltage Reference

    Directory of Open Access Journals (Sweden)

    El Hafed Boufouss

    2013-12-01

    Full Text Available This paper presents an ultra-low power CMOS voltage reference circuit which is robust under biomedical extreme conditions, such as high temperature and high total ionized dose (TID radiation. To achieve such performances, the voltage reference is designed in a suitable 130 nm Silicon-on-Insulator (SOI industrial technology and is optimized to work in the subthreshold regime of the transistors. The design simulations have been performed over the temperature range of -40–200 °C and for different process corners. Robustness to radiation was simulated using custom model parameters including TID effects, such as mobilities and threshold voltages degradation. The proposed circuit has been tested up to high total radiation dose, i.e., 1 Mrad (Si performed at three different temperatures (room temperature, 100 °C and 200 °C. The maximum drift of the reference voltage VREF depends on the considered temperature and on radiation dose; however, it remains lower than 10% of the mean value of 1.5 V. The typical power dissipation at 2.5 V supply voltage is about 20 μW at room temperature and only 75 μ W at a high temperature of 200 °C. To understand the effects caused by the combination of high total ionizing dose and temperature on such voltage reference, the threshold voltages of the used SOI MOSFETs were extracted under different conditions. The evolution of VREF and power consumption with temperature and radiation dose can then be explained in terms of the different balance between fixed oxide charge and interface states build-up. The total occupied area including pad-ring is less than 0.09 mm2.

  13. Ultra-low-loss inverted taper coupler for silicon-on-insulator ridge waveguide

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Ou, Haiyan; Yvind, Kresten; Hvam, Jørn Märcher

    2010-01-01

    width of the silicon-on-insulator waveguide from 450 nm down to less than 15 nm applying a thermal oxidation process. Two inverted taper couplers are integrated with a 3-mm long silicon-on-insulator ridge waveguide in the fabricated sample. The measured coupling losses of the inverted taper coupler for......An ultra-low-loss coupler for interfacing a silicon-on-insulator ridge waveguide and a single-mode fiber in both polarizations is presented. The inverted taper coupler, embedded in a polymer waveguide, is optimized for both the transverse-magnetic and transverse-electric modes through tapering the...

  14. Growth of light-emitting SiGe heterostructures on strained silicon-on-insulator substrates with a thin oxide layer

    Energy Technology Data Exchange (ETDEWEB)

    Baidakova, N. A., E-mail: banatale@ipmras.ru [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Bobrov, A. I. [University of Nizhny Novgorod (Russian Federation); Drozdov, M. N.; Novikov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Pavlov, D. A. [University of Nizhny Novgorod (Russian Federation); Shaleev, M. V.; Yunin, P. A.; Yurasov, D. V.; Krasilnik, Z. F. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2015-08-15

    The possibility of using substrates based on “strained silicon on insulator” structures with a thin (25 nm) buried oxide layer for the growth of light-emitting SiGe structures is studied. It is shown that, in contrast to “strained silicon on insulator” substrates with a thick (hundreds of nanometers) oxide layer, the temperature stability of substrates with a thin oxide is much lower. Methods for the chemical and thermal cleaning of the surface of such substrates, which make it possible to both retain the elastic stresses in the thin Si layer on the oxide and provide cleaning of the surface from contaminating impurities, are perfecte. It is demonstrated that it is possible to use the method of molecular-beam epitaxy to grow light-emitting SiGe structures of high crystalline quality on such substrates.

  15. Analysis of surface and interface charge interactions in silicon on insulator (SOI) substrates

    Science.gov (United States)

    Lukasiak, L.; Roman, P.; Jakubowski, A.; Ruzyllo, J.

    2001-01-01

    Surface photovoltage (SPV) measurements may provide an effective method for determining electrical properties of silicon on insulator (SOI) surfaces. In the experimental part of this work the use of the non-contact SPV-based method of surface charge profiling (SCP) in the monitoring of surface charges is explored. It was demonstrated that application of this method is constrained by the interactions between charges on the Si surface and at the interface between the Si active layer and buried oxide (box). These interactions are subsequently modeled and related to the SCP measurements. It is demonstrated that at a given doping level, the thickness of the active layer and density of charge associated with the box are factors predetermining the effectiveness of this method in SOI surface characterization. Through modeling, the SOI substrate parameter space for which the SCP method can yield useful information is defined.

  16. Analytical model of LDMOS with a double step buried oxide layer

    Science.gov (United States)

    Yuan, Song; Duan, Baoxing; Cao, Zhen; Guo, Haijun; Yang, Yintang

    2016-09-01

    In this paper, a two-dimensional analytical model is established for the Buried Oxide Double Step Silicon On Insulator structure proposed by the authors. Based on the two-dimensional Poisson equation, the analytic expressions of the surface electric field and potential distributions for the device are achieved. In the BODS (Buried Oxide Double Step Silicon On Insulator) structure, the buried oxide layer thickness changes stepwise along the drift region, and the positive charge in the drift region can be accumulated at the corner of the step. These accumulated charge function as the space charge in the depleted drift region. At the same time, the electric field in the oxide layer also varies with the different drift region thickness. These variations especially the accumulated charge will modulate the surface electric field distribution through the electric field modulation effects, which makes the surface electric field distribution more uniform. As a result, the breakdown voltage of the device is improved by 30% compared with the conventional SOI structure. To verify the accuracy of the analytical model, the device simulation software ISE TCAD is utilized, the analytical values are in good agreement with the simulation results by the simulation software. That means the established two-dimensional analytical model for BODS structure is valid, and it also illustrates the breakdown voltage enhancement by the electric field modulation effect sufficiently. The established analytical models will provide the physical and mathematical basis for further analysis of the new power devices with the patterned buried oxide layer.

  17. Residual stresses at cavity corners in silicon-on-insulator bonded wafers

    International Nuclear Information System (INIS)

    Uncontrolled residual stresses in both integrated circuit and micro-electro-mechanical system applications may affect device performance and reliability, making microscale experimental analysis of the residual stresses an essential part of process and quality control. This work studies the residual stresses generated from different processing parameters common in the manufacture of silicon-on-insulator wafers with buried cavities (cavity-SOI). The buried cavities can concentrate the residual stresses and generate localized mechanical failures. Infrared photoelasticity and optical profilometry are used here to analyze the stress state in wafers after each of several critical processing steps, each with different process parameters. It is found that the residual stresses associated with cavities in the bonded wafers may significantly increase depending upon the oxidation/etching steps and that the stress magnitude is dependent upon the particular etched cavity geometry. Process-dependent stress states and their generation mechanisms are explained for each processing step. The oxide layer grown on cavity sidewalls is found to significantly impact the residual stress at the cavity corners, with a strong dependence on buried oxide layer thickness. By selecting appropriate processing steps and parameters, the magnitude and orientation of the residual stress in the cavity-SOI wafers can be controlled to enhance reliability. (paper)

  18. Spreading-resistance temperature sensor on silicon-on-insulator

    OpenAIRE

    Lai, PT; Li, B.; Chan, CL; Sin, JKO

    1999-01-01

    A spreading-resistance temperature (SRT) sensor is fabricated on silicon-on-insulator (SOI) substrate and achieves promising characteristics as compared with similar SRT sensor on bulk silicon wafer. Moreover, experimental results show that the maximum operating temperature of thin-film (1.2 μm) SOI SRT sensor can reach 450 °C, much higher than 350 °C of thick-film (10 μm) SOI SRT sensor under the same current level. With complete oxide isolation, this sensor structure can be potentially used...

  19. Silicon on insulator self-aligned transistors

    Science.gov (United States)

    McCarthy, Anthony M.

    2003-11-18

    A method for fabricating thin-film single-crystal silicon-on-insulator (SOI) self-aligned transistors. Standard processing of silicon substrates is used to fabricate the transistors. Physical spaces, between the source and gate, and the drain and gate, introduced by etching the polysilicon gate material, are used to provide connecting implants (bridges) which allow the transistor to perform normally. After completion of the silicon substrate processing, the silicon wafer is bonded to an insulator (glass) substrate, and the silicon substrate is removed leaving the transistors on the insulator (glass) substrate. Transistors fabricated by this method may be utilized, for example, in flat panel displays, etc.

  20. Modeling of a triple reduced surface field silicon-on-insulator lateral double-diffused metal-oxide-semiconductor field-effect transistor with low on-state resistance

    Science.gov (United States)

    Yu-Ru, Wang; Yi-He, Liu; Zhao-Jiang, Lin; Dong, Fang; Cheng-Zhou, Li; Ming, Qiao; Bo, Zhang

    2016-02-01

    An analytical model for a novel triple reduced surface field (RESURF) silicon-on-insulator (SOI) lateral double-diffused metal-oxide-semiconductor (LDMOS) field effect transistor with n-type top (N-top) layer, which can obtain a low on-state resistance, is proposed in this paper. The analytical model for surface potential and electric field distributions of the novel triple RESURF SOI LDMOS is presented by solving the two-dimensional (2D) Poisson’s equation, which can also be applied to single, double and conventional triple RESURF SOI structures. The breakdown voltage (BV) is formulized to quantify the breakdown characteristic. Besides, the optimal integrated charge of N-top layer (Qntop) is derived, which can give guidance for doping the N-top layer. All the analytical results are well verified by numerical simulation results, showing the validity of the presented model. Hence, the proposed model can be a good tool for the device designers to provide accurate first-order design schemes and physical insights into the high voltage triple RESURF SOI device with N-top layer. Project supported by the National Natural Science Foundation of China (Grant No. 61376080), the Natural Science Foundation of Guangdong Province, China (Grant No. 2014A030313736), and the Fundamental Research Funds for the Central Universities, China (Grant No. ZYGX2013J030).

  1. Silicon-on-Insulating Multi-Layers for Total-Dose Irradiation Hardness

    Institute of Scientific and Technical Information of China (English)

    ZHANG En-Xia; YI Wan-Bing; LIU Xiang-Hua; CHEN Meng; LIU Zhong-Li; Wang Xi

    2004-01-01

    @@ Silicon-on-insulating multi-layer (SOIM) materials were fabricated by co-implantation of oxygen and nitrogen ions with different energies and doses. The multilayer microstructure was investigated by cross-sectional transmission electron microscopy. P-channel metal-oxide-semiconductor (PMOS) transistors and metal-semiconductorinsulator-semiconductor (MSIS) capacitors were produced by these materials.

  2. Silicon-on-insulator integrated optic transceivers

    Science.gov (United States)

    Morris, Robin J.

    1997-04-01

    Silicon-on-insulator offers the chance to produce integrated optical `circuits' with properties which are appropriate even for demanding applications. Developments in SOI waveguide technology have been combined with the well- developed micro-engineering properties of silicon for use in fields such as telecommunication and sensors. An integrated optical transceiver is selected as an example with which to describe the features of the technology. The design will be used to illustrate the benefits brought by the use of SOI waveguide elements. These functional `building blocks' include alignment features, integrated mode-matching waveguide tapers, tap-off couplers and low back-reflection interfaces. Further possible integrated elements are described, including WDMs, as relevant to optical transceiver technology. The economic and technical drivers and difficulties surrounding the convergence of electrical, CMOS-like and optical SOI technologies are also considered. There is a spreading acceptance that low-cost motherboard technology is needed, to realize volume production of optical transceivers. A range of materials solutions have been reported. The relative merits of SOI technology are discussed. Motherboard techniques provide a platform for precise optical alignment between components. The SOI approach can deliver self-aligned waveguide and hybridization features--such as fiber attach or laser diode connections--and includes the ability to adapt to laser diode and optical fiber near-field characteristics.

  3. Space and military radiation effects in silicon-on-insulator devices

    International Nuclear Information System (INIS)

    Advantages in transient ionizing and single-event upset (SEU) radiation hardness of silicon-on-insulator (SOI) technology spurred much of its early development. Both of these advantages are a direct result of the reduced charge collection volume inherent to SOI technology. The fact that SOI transistor structures do not include parasitic n-p-n-p paths makes them immune to latchup. Even though considerable improvement in transient and single-event radiation hardness can be obtained by using SOI technology, there are some attributes of SOI devices and circuits that tend to limit their overall hardness. These attributes include the bipolar effect that can ultimately reduce the hardness of SOI ICs to SEU and transient ionizing radiation, and charge buildup in buried and sidewall oxides that can degrade the total-dose hardness of SOI devices. Nevertheless, high-performance SOI circuits can be fabricated that are hardened to both space and nuclear radiation environments, and radiation-hardened systems remain an active market for SOI devices. The effects of radiation on SOI MOS devices are reviewed

  4. Radiation effects in advanced multiple gate and silicon-on-insulator transistors

    International Nuclear Information System (INIS)

    The aim of this review paper is to describe in a comprehensive manner the current understanding of the radiation response of state-of-the-art Silicon-on-Insulator (SOI) and FinFET CMOS technologies. Total Ionizing Dose (TID) response, heavy-ion micro-dose effects and single-event effects (SEEs) will be discussed. It is shown that a very high TID tolerance can be achieved by narrow-fin SOI FinFET architectures, while bulk FinFETs may exhibit similar TID response to the planar devices. Due to the vertical nature of FinFETs, a specific heavy-ion response can be obtained, whereby the angle of incidence becomes highly important with respect to the vertical sidewall gates. With respect to SEE, the buried oxide in the SOI FinFETs suppresses the diffusion tails from the charge collection in the substrate compared to the planar bulk FinFET devices. Channel lengths and fin widths are now comparable to, or smaller than the dimensions of the region affected by the single ionizing ions or lasers used in testing. This gives rise to a high degree of sensitivity to individual device parameters and source-drain shunting during ion-beam or laser-beam SEE testing. Simulations are used to illuminate the mechanisms observed in radiation testing and the progress and needs for the numerical modeling/ simulation of the radiation response of advanced SOI and FinFET transistors are highlighted. (authors)

  5. Analytical model of LDMOS with a single step buried oxide layer

    Science.gov (United States)

    Yuan, Song; Duan, Baoxing; Cao, Zhen; Guo, Haijun; Yang, Yintang

    2016-09-01

    In this paper, a two-dimensional analytical model is established for the Single-Step Buried Oxide SOI structure proposed by the authors. Based on the two-dimensional Poisson equation, the analytic expression of the surface electric field and potential distributions for the device is achieved. In the SBOSOI (Single-Step Buried Oxide Silicon On Insulator) structure, the buried oxide layer thickness changes stepwise along the drift region, and the electric field in the oxide layer also varies with the different buried oxide layer thickness. These variations will modulate the surface electric field distribution through the electric field modulation effects, which makes the surface electric field distribution more uniform. As a result, the breakdown voltage of the device is improved by 60% compared with the conventional SOI structure. To verify the accuracy of the analytical model, the device simulation software ISE TCAD is utilized, the analytical values are in good agreement with the simulation results by the simulation software. The results verified the established two-dimensional analytical model for SBOSOI structure is valid, and it also illustrates the breakdown voltage enhancement by the electric field modulation effect sufficiently. The established analytical models will provide the physical and mathematical basis for further analysis of the new power devices with the patterned buried oxide layer.

  6. Single mode and polarization independence in the strained silicon-on-insulator rib waveguides

    Directory of Open Access Journals (Sweden)

    Milošević Milan M.

    2008-01-01

    Full Text Available In this paper we investigate the most popular silicon waveguide structures in the form of a silicon-on-insulator (SOI rib waveguide. Single mode and birefringence free conditions in these relatively small waveguides are discussed and the influence of the top oxide cladding stress is analyzed. Field profiles for a wide range of waveguide cross section shapes and dimensions are systematically considered. Design guidelines for this type of SOI waveguides are presented.

  7. Radiation effects in silicon-on-insulator transistors with back-gate control method fabricated with OKI Semiconductor 0.20 μm FD-SOI technology

    International Nuclear Information System (INIS)

    Bonded silicon-on-insulator (SOI) wafers have the capability of realizing monolithic pixel devices, where the silicon resistivity is optimized separately for the electronics and detector parts. Using UNIBOND wafers, we are developing monolithic pixel devices fabricated with OKI Semiconductor 0.20 μm FD-SOI technology. A set of PMOS and NMOS transistors were irradiated with protons in order to investigate the total ionization dose effect in transistor operation. We evaluated also the devices with a back-gate control electrode added underneath the buried oxide layer. Primary radiation effect appears in transistor threshold shifts, which can be explained by charge traps in the oxide layers and charge states created at the silicon-oxide boundaries. We discuss the possibility of TCAD simulation for evaluation of the charge densities.

  8. A Novel Non-Destructive Silicon-on-Insulator Nonvolatile Memory - LDRD 99-0750 Final Report; TOPICAL

    International Nuclear Information System (INIS)

    Defects in silicon-on-insulator (SOI) buried oxides are normally considered deleterious to device operation. Similarly, exposing devices to hydrogen at elevated temperatures often can lead to radiation-induced charge buildup. However, in this work, we take advantage of as-processed defects in SOI buried oxides and moderate temperature hydrogen anneals to generate mobile protons in the buried oxide to form the basis of a ''protonic'' nonvolatile memory. Capacitors and fully-processed transistors were fabricated. SOI buried oxides are exposed to hydrogen at moderate temperatures using a variety of anneal conditions to optimize the density of mobile protons. A fast ramp cool down anneal was found to yield the maximum number of mobile protons. Unfortunately, we were unable to obtain uniform mobile proton concentrations across a wafer. Capacitors were irradiated to investigate the potential use of protonic memories for space and weapon applications. Irradiating under a negative top-gate bias or with no applied bias was observed to cause little degradation in the number of mobile protons. However, irradiating to a total dose of 100 krad(SiO(sub 2)) under a positive top-gate bias caused approximately a 100% reduction in the number of mobile protons. Cycling capacitors up to 10(sup 4) cycles had little effect on the switching characteristics. No change in the retention characteristics were observed for times up to 3 x 10(sup 4) s for capacitors stored unbiased at 200 C. These results show the proof-of-concept for a protonic nonvolatile memory. Two memory architectures are proposed for a protonic non-destructive, nonvolatile memory

  9. Integrated programmable photonic filter on the silicon -on- insulator platform

    DEFF Research Database (Denmark)

    Liao, Shasha; Ding, Yunhong; Peucheret, Christophe; Yang, Ting; Dong, Jianji; Zhang, Xinliang

    2014-01-01

    We propose and demonstrate a silicon - on - insulator (SOI) on - chip programmable filter based on a four - tap finite impulse response structure. The photonic filter is programmable thanks to amplitude and phase modulation of each tap controlled by thermal heater s. We further demonstrate the...

  10. The breakdown mechanism of a high-side pLDMOS based on a thin-layer silicon-on-insulator structure

    Institute of Scientific and Technical Information of China (English)

    Zhao Yuan-Yuan; Qiao Ming; Wang Wei-Bin; Wang Meng; Zhang Bo

    2012-01-01

    A high-side thin-layer silicon-on-insulator (SOI) pLDMOS is proposed,adopting field implant (FI) and multiple field plate (MFP) technologies.The breakdown mechanisms of back gate (BG) turn-on,surface channel punch-through,and vertical and lateral avalanche breakdown are investigated by setting up analytical models,simulating related parameters and verifying experimentally.The device structure is optimized based on the above research.The shallow junction achieved through FI technology attenuates the BG effect,the optimized channel length eliminates the surface channel punch-through,the advised thickness of the buried oxide dispels the vertical avalanche breakdown,and the MFP technology avoids premature lateral avalanche breakdown by modulating the electric field distribution.Finally,for the first time,a 300 V high-side pLDMOS is experimentally realized on a 1.5 μm thick thin-layer SOI.

  11. Superconducting cavity-electromechanics on silicon-on-insulator

    OpenAIRE

    Dieterle, Paul B.; Kalaee, Mahmoud; FINK, Johannes; Painter, Oskar

    2016-01-01

    Fabrication processes involving anhydrous hydrofluoric vapor etching are developed to create high-$Q$ aluminum superconducting microwave resonators on free-standing silicon membranes formed from a silicon-on-insulator wafer. Using this fabrication process, a high-impedance $8.9$GHz coil resonator is coupled capacitively with large participation ratio to a $9.7$MHz micromechanical resonator. Two-tone microwave spectroscopy and radiation pressure back-action are used to characterize the coupled...

  12. A novel partial SOI LDMOSFET with periodic buried oxide for breakdown voltage and self heating effect enhancement

    Science.gov (United States)

    Jamali Mahabadi, S. E.; Rajabi, Saba; Loiacono, Julian

    2015-09-01

    In this paper a partial silicon on insulator (PSOI) lateral double diffused metal oxide semiconductor field effect transistor (LDMOSFET) with periodic buried oxide layer (PBO) for enhancing breakdown voltage (BV) and self-heating effects (SHEs) is proposed for the first time. This new structure is called periodic buried oxide partial silicon on insulator (PBO-PSOI). In this structure, periodic small pieces of SiO2 were used as the buried oxide (BOX) layer in PSOI to modulate the electric field in the structure. It was demonstrated that the electric field is distributed more evenly by producing additional electric field peaks, which decrease the common peaks near the drain and gate junctions in the PBO-PSOI structure. Hence, the area underneath the electric field curve increases which leads to higher breakdown voltage. Also a p-type Si window was introduced in the source side to force the substrate to share the vertical voltage drop, leading to a higher vertical BV. Furthermore, the Si window under the source and those between periodic pieces of SiO2 create parallel conduction paths between the active layer and substrate thereby alleviating the SHEs. Simulations with the two dimensional ATLAS device simulator from the Silvaco suite of simulation tools show that the BV of PBO-PSOI is 100% higher than that of the conventional partial SOI (C-PSOI) structure. Furthermore the PBO-PSOI structure alleviates SHEs to a greater extent than its C-PSOI counterpart. The achieved drain current for the PBO-PSOI structure (100 μA), at drain-source voltage of VDS = 100 V and gate-source voltage of VGS = 25 V, is shown to be significantly larger than that in C-PSOI and fully depleted SOI (FD-SOI) structures (87 μA and 51 μA respectively). Drain current can be further improved at the expense of BV by increasing the doping of the drift region.

  13. A high voltage silicon-on-insulator lateral insulated gate bipolar transistor with a reduced cell-pitch

    International Nuclear Information System (INIS)

    A high voltage (> 600 V) integrable silicon-on-insulator (SOI) trench-type lateral insulated gate bipolar transistor (LIGBT) with a reduced cell-pitch is proposed. The LIGBT features multiple trenches (MTs): two oxide trenches in the drift region and a trench gate extended to the buried oxide (BOX). Firstly, the oxide trenches enhance electric field strength because of the lower permittivity of oxide than that of Si. Secondly, oxide trenches bring in multi-directional depletion, leading to a reshaped electric field distribution and an enhanced reduced-surface electric-field (RESURF) effect. Both increase the breakdown voltage (BV). Thirdly, oxide trenches fold the drift region around the oxide trenches, leading to a reduced cell-pitch. Finally, the oxide trenches enhance the conductivity modulation, resulting in a high electron/hole concentration in the drift region as well as a low forward voltage drop (Von). The oxide trenches cause a low anode—cathode capacitance, which increases the switching speed and reduces the turn-off energy loss (Eoff). The MT SOI LIGBT exhibits a BV of 603 V at a small cell-pitch of 24 μm, a Von of 1.03 V at 100 A/cm−2, a turn-off time of 250 ns and Eoff of 4.1×10−3 mJ. The trench gate extended to BOX synchronously acts as dielectric isolation between high voltage LIGBT and low voltage circuits, simplifying the fabrication processes. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  14. A high voltage silicon-on-insulator lateral insulated gate bipolar transistor with a reduced cell-pitch

    Institute of Scientific and Technical Information of China (English)

    Luo Xiao-Rong; Wang Qi; Yao Guo-Liang; Wang Yuan-Gang; Lei Tian-Fei; Wang Pei; Jiang Yong-Heng

    2013-01-01

    A high voltage (> 600 V) integrable silicon-on-insulator (SOI) trench-type lateral insulated gate bipolar transistor (LIGBT) with a reduced cell-pitch is proposed.The LIGBT features multiple trenches (MTs):two oxide trenches in the drift region and a trench gate extended to the buried oxide (BOX).Firstly,the oxide trenches enhance electric field strength because of the lower permittivity of oxide than that of Si.Secondly,oxide trenches bring in multi-directional depletion,leading to a reshaped electric field distribution and an enhanced reduced-surface electric-field (RESURF) effect.Both increase the breakdown voltage (BV).Thirdly,oxide trenches fold the drift region around the oxide trenches,leading to a reduced cell-pitch.Finally,the oxide trenches enhance the conductivity modulation,resulting in a high electron/hole concentration in the drift region as well as a low forward voltage drop (Von).The oxide trenches cause a low anode-cathode capacitance,which increases the switching speed and reduces the turn-off energy loss (Eoff).The MT SOI LIGBT exhibits a BV of 603 V at a small cell-pitch of 24 μtm,a Von of 1.03 V at 100 A/cm-2,a turn-off time of 250 ns and Eoff of 4.1 × 10 3 mJ.The trench gate extended to BOX synchronously acts as dielectric isolation between high voltage LIGBT and low voltage circuits,simplifying the fabrication processes.

  15. Topology optimized design for silicon-on-insulator mode converter

    DEFF Research Database (Denmark)

    Frellsen, Louise Floor; Frandsen, Lars Hagedorn; Ding, Yunhong;

    2015-01-01

    The field of photonic integrated circuits (PICs) has attracted interest in recent years as they allow high device density while requiring only low operating power. The possibility of exploiting mode division multiplexing (MDM) in future optical communication networks is being investigated as a...... and the first higher order odd mode (TE1) in a photonic wire. The design is to be fabricated in silicon-on-insulator (SOI) material, and previous work has shown excellent correspondence between simulations and experimental results for 3D TO [7]....

  16. Evaluation of strained silicon on insulator for SET based single donor spin read-out

    Science.gov (United States)

    Sharma, Peter; Ten Eyck, Greg; Ward, Daniel; Dominguez, Jason; Childs, Kenton; Wendt, Joel; Lilly, Michael; Carroll, Malcolm

    2015-03-01

    Recent successes in realizing single donor control and achieving very high fidelity gate operations has driven interest in silicon-based donor qubits. A number of proposals for donor to donor coupling rely on vertical field for Stark shift and ionization to a nearby interface. Back gating silicon on insulator is one approach to achieving sufficient field strengths. We present low temperature measurements of back gated FET structures and donor implanted SETs fabricated from strained silicon on insulator substrates with a low doped handle. This strained silicon system is useful for studying the effects of strain on both single donor physics and may provide insight into the behavior of strained silicon channels for quantum dots. We use FET thresholds to characterize the oxide/Si defect density. Back gating influences the transient time response, mobility, and FET threshold. These parameters are also modified by above band gap light illumination. Two transport channels are observed, which also strongly depend on back gate voltage and illumination. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy Office of Science. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  17. Superconducting Cavity Electromechanics on a Silicon-on-Insulator Platform

    Science.gov (United States)

    Dieterle, Paul B.; Kalaee, Mahmoud; Fink, Johannes M.; Painter, Oskar

    2016-07-01

    Fabrication processes involving anhydrous hydrofluoric vapor etching are developed to create high-Q aluminum superconducting microwave resonators on free-standing silicon membranes formed from a silicon-on-insulator wafer. Using this fabrication process, a high-impedance 8.9-GHz coil resonator is coupled capacitively with a large participation ratio to a 9.7-MHz micromechanical resonator. Two-tone microwave spectroscopy and radiation pressure backaction are used to characterize the coupled system in a dilution refrigerator down to temperatures of Tf=11 mK , yielding a measured electromechanical vacuum coupling rate of g0/2 π =24.6 Hz and a mechanical resonator Q factor of Qm=1.7 ×1 07. Microwave backaction cooling of the mechanical resonator is also studied, with a minimum phonon occupancy of nm≈16 phonons being realized at an elevated fridge temperature of Tf=211 mK .

  18. Lithographically defined few-electron silicon quantum dots based on a silicon-on-insulator substrate

    Energy Technology Data Exchange (ETDEWEB)

    Horibe, Kosuke; Oda, Shunri [Department of Physical Electronics and Quantum Nanoelectronics Research Center, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8552 (Japan); Kodera, Tetsuo, E-mail: kodera.t.ac@m.titech.ac.jp [Department of Physical Electronics and Quantum Nanoelectronics Research Center, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8552 (Japan); Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505 (Japan)

    2015-02-23

    Silicon quantum dot (QD) devices with a proximal single-electron transistor (SET) charge sensor have been fabricated in a metal-oxide-semiconductor structure based on a silicon-on-insulator substrate. The charge state of the QDs was clearly read out using the charge sensor via the SET current. The lithographically defined small QDs enabled clear observation of the few-electron regime of a single QD and a double QD by charge sensing. Tunnel coupling on tunnel barriers of the QDs can be controlled by tuning the top-gate voltages, which can be used for manipulation of the spin quantum bit via exchange interaction between tunnel-coupled QDs. The lithographically defined silicon QD device reported here is technologically simple and does not require electrical gates to create QD confinement potentials, which is advantageous for the integration of complicated constructs such as multiple QD structures with SET charge sensors for the purpose of spin-based quantum computing.

  19. Supercoupling effect in short-channel ultrathin fully depleted silicon-on-insulator transistors

    International Nuclear Information System (INIS)

    Supercoupling effect prevents the simultaneous formation of inversion and accumulation channels at the two interfaces of ultrathin silicon-on-insulator metal-oxide-semiconductor field-effect transistor. Our work highlights that short-channel effects enhance supercoupling and turn it into a two-dimensional mechanism. The lateral influence of source and drain terminals is evidenced with experimental data and examined by 2D numerical simulations which reveal the roles of gate length and drain bias. The critical Si-film thickness, below which supercoupling arises, is significantly increased in short-channel transistors. The impact of back-gate and drain bias, BOX thickness, and quantum effects is documented and practical applications are discussed

  20. Lithographically defined few-electron silicon quantum dots based on a silicon-on-insulator substrate

    Science.gov (United States)

    Horibe, Kosuke; Kodera, Tetsuo; Oda, Shunri

    2015-02-01

    Silicon quantum dot (QD) devices with a proximal single-electron transistor (SET) charge sensor have been fabricated in a metal-oxide-semiconductor structure based on a silicon-on-insulator substrate. The charge state of the QDs was clearly read out using the charge sensor via the SET current. The lithographically defined small QDs enabled clear observation of the few-electron regime of a single QD and a double QD by charge sensing. Tunnel coupling on tunnel barriers of the QDs can be controlled by tuning the top-gate voltages, which can be used for manipulation of the spin quantum bit via exchange interaction between tunnel-coupled QDs. The lithographically defined silicon QD device reported here is technologically simple and does not require electrical gates to create QD confinement potentials, which is advantageous for the integration of complicated constructs such as multiple QD structures with SET charge sensors for the purpose of spin-based quantum computing.

  1. Silicon-on-insulator integrated tunable polarization controller (Conference Presentation)

    Science.gov (United States)

    Sarmiento-Merenguel, Jose-Dario; Alonso-Ramos, Carlos; Halir, Robert; Le Roux, Xavier; Vivien, Laurent; Cheben, Pavel; Durán-Valdeiglesias, Elena; Molina-Fernández, Iñigo; Marris-Morini, Delphine; Xu, Danxia; Schmid, Jens H.; Janz, Siegfried; Ortega-Moñux, Alejandro

    2016-05-01

    Polarization management is a key functionality in many photonic applications, including optical communications, imaging or quantum information. Developing integrated devices capable of reliably controlling polarization state would result in compact and low cost circuits with improved stability compared with fiber or bulk optics solutions. However, stringent fabrication tolerances make the integration of polarization managing elements highly challenging. The main challenge in polarization controllers, composed by polarization rotators and polarization phase shifters, is to precisely control rotation angle in integrated polarization rotators. Proposed solutions typically require sophisticated fabrication processes or extremely tight fabrication tolerances, seriously hindering their practical application. Here we present a technology independent polarization controller scheme that relies on phase shifters to largely relax fabrication tolerances of polarization rotators. In addition, these phase shifters enable dynamic wavelength tuning. In our scheme, three polarization rotation elements are interconnected with two tunable phase shifters to adjust the polarization extinction ratio, while an output polarization phase shifter is used to select the relative phase. This way we can achieve any desired output state of polarization. We have implemented this scheme in the silicon-on-insulator platform, experimentally demonstrating a record polarization extinction range of 40 dB (± 20 dB) with a 98% coverage of the Poincaré sphere. Furthermore, the device is tunable in the complete C-band. These results constitute, to the best of our knowledge, the highest polarization extinction range achieved in a fully integrated device.

  2. Hot-carrier-induced linear drain current and threshold voltage degradation for thin layer silicon-on-insulator field P-channel lateral double-diffused metal-oxide-semiconductor

    International Nuclear Information System (INIS)

    Hot-carrier-induced linear drain current (Idlin) and threshold voltage (Vth) degradations for the thin layer SOI field p-channel lateral double-diffused MOS (pLDMOS) are investigated. Two competition degradation mechanisms are revealed and the hot-carrier conductance modulation model is proposed. In the channel, hot-hole injection induced positive oxide trapped charge and interface trap gives rise to the Vth increasing and the channel conductance (Gch) decreasing, then reduces Idlin. In the p-drift region, hot-electron injection induced negative oxide trapped charge enhances the conductance of drift doping resistance (Gd), and then increases Idlin. Consequently, the eventual Idlin degradation is controlled by the competition of the two mechanisms due to conductance modulation in the both regions. Based on the model, it is explained that the measured Idlin anomalously increases while the Vth is increasing with power law. The thin layer field pLDMOS exhibits more severe Vth instability compared with thick SOI layer structure; as a result, it should be seriously evaluated in actual application in switching circuit

  3. Hot-carrier-induced linear drain current and threshold voltage degradation for thin layer silicon-on-insulator field P-channel lateral double-diffused metal-oxide-semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xin; Qiao, Ming; He, Yitao; Li, Zhaoji; Zhang, Bo, E-mail: bozhang@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China)

    2015-11-16

    Hot-carrier-induced linear drain current (I{sub dlin}) and threshold voltage (V{sub th}) degradations for the thin layer SOI field p-channel lateral double-diffused MOS (pLDMOS) are investigated. Two competition degradation mechanisms are revealed and the hot-carrier conductance modulation model is proposed. In the channel, hot-hole injection induced positive oxide trapped charge and interface trap gives rise to the V{sub th} increasing and the channel conductance (G{sub ch}) decreasing, then reduces I{sub dlin}. In the p-drift region, hot-electron injection induced negative oxide trapped charge enhances the conductance of drift doping resistance (G{sub d}), and then increases I{sub dlin}. Consequently, the eventual I{sub dlin} degradation is controlled by the competition of the two mechanisms due to conductance modulation in the both regions. Based on the model, it is explained that the measured I{sub dlin} anomalously increases while the V{sub th} is increasing with power law. The thin layer field pLDMOS exhibits more severe V{sub th} instability compared with thick SOI layer structure; as a result, it should be seriously evaluated in actual application in switching circuit.

  4. Electromechano-optically tuned ring resonator in silicon on insulator, monolithically integrated with a microcantilever

    NARCIS (Netherlands)

    Kauppinen, Lasse J.; Abdulla, Shahina M.C.; Krijnen, Gijs J.M.; Pollnau, Markus; Ridder, de René M.

    2011-01-01

    Monolithic integration of a micromechanical cantilever with an optical ring resonator in silicon on insulator is demonstrated. The ring can be tuned over a 50 pm wavelength range by applying 8.5 V, without affecting its Q-factor.

  5. ARROW-based silicon-on-insulator photonic crystal waveguides with reduced losses

    OpenAIRE

    Lavrinenko, Andrei V.; Novitsky, Andrey V.; Zhilko, Vitaly V.

    2006-01-01

    We employ an antiresonant reflecting layers arrangement with silicon-on-insulator based photonic crystal waveguides. The 3D FDTD numerical modelling reveals improved transmission in such structures with a promising potential for their application in photonic circuits.

  6. First order Bragg grating filters in silicon on insulator waveguides

    Science.gov (United States)

    Waugh, Peter Michael

    2008-08-01

    The subject of this project is the design; analysis, fabrication and characterisation of first order Bragg Grating optical filters in Silicon-on-Insulator (SOI) planar waveguides. It is envisaged that this work will result in the possibility of Bragg Grating filters for use in Silicon Photonics. It is the purpose of the work to create as far as is possible flat surface waveguides so as to facilitate Thermo-Optic tuning and also the incorporation into rib-waveguide Silicon Photonics. The spectral response of the shallow Bragg Gratings was modelled using Coupled Mode Theory (CMT) by way of RSoft Gratingmod TM. Also the effect of having a Bragg Grating with alternate layers of refractive index of 1.5 and 3.5 was simulated in order to verify that Silica and Silicon layered Bragg Gratings could be viable. A series of Bragg Gratings were patterned on 1.5 micron SOI at Philips in Eindhoven, Holland to investigate the variation of grating parameters with a) the period of the gratings b) the mark to space ratio of the gratings and c) the length of the region converted to Bragg Gratings (i.e. the number of grating period repetitions). One set of gratings were thermally oxidised at Philips in Eindhoven and another set were ion implanted with Oxygen ions at the Ion Beam Facility, University of Surrey, England. The gratings were tested and found to give transmission minima at approximately 1540 nanometres and both methods of creating flat surfaces were found to give similar minima. Atomic Force Microscopy was applied to the grating area of the as-implanted samples in the Advanced Technology Institute, University of Surrey, which were found to have surface undulations in the order of 60 nanometres.

  7. ARROW-based silicon-on-insulator photonic crystal waveguides with reduced losses

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei; Novitsky, A.; Zhilko, V.V.

    We employ an antiresonant reflecting layers arrangement with silicon-on-insulator based photonic crystal waveguides. The 3D FDTD numerical modelling reveals improved transmission in such structures with a promising potential for their application in photonic circuits.......We employ an antiresonant reflecting layers arrangement with silicon-on-insulator based photonic crystal waveguides. The 3D FDTD numerical modelling reveals improved transmission in such structures with a promising potential for their application in photonic circuits....

  8. Microwave photonic phase shifter based on tunable silicon-on-insulator microring resonator

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Xue, Weiqi; Frandsen, Lars Hagedorn; Ou, Haiyan; Yvind, Kresten; Hvam, Jørn Märcher

    We demonstrate a microwave photonic phase shifter based on an electrically tunable silicon-on-insulator microring resonator. A continuously tunable phase shift of up to 315° at a microwave frequency of 15GHz is obtained.......We demonstrate a microwave photonic phase shifter based on an electrically tunable silicon-on-insulator microring resonator. A continuously tunable phase shift of up to 315° at a microwave frequency of 15GHz is obtained....

  9. Silicon on insulator bipolar junction transistors for flexible microwave applications

    Science.gov (United States)

    Bavier, John McGoldrick

    Microwave frequency flexible electronic devices require a high quality semiconducting material and a set of fabrication techniques that are compatible with device integration onto flexible polymer substrates. Over the past ten years, monocrystalline silicon nanomembranes (SiNMs) have been studied as a flexible semiconducting material that is compatible with industrial Si processing. Fabricated from commercial silicon on insulator (SOI) wafers, SiNMs can be transferred to flexible substrates using a variety of techniques. Due to their high carrier mobilities, SiNMs are a promising candidate for flexible microwave frequency devices. This dissertation presents fabrication techniques for flexible SiNM devices in general, as well as the progress made towards the development of a microwave frequency SiNM bipolar junction transistor (BJT). In order to overcome previous limitations associated with adhesion, novel methods for transfer printing of metal films and SiNMs are presented. These techniques enable transfer printing of a range of metal films and improve the alignment of small transfer printed SiNM devices. Work towards the development of a microwave frequency BJT on SOI for SiNM devices is also described. Utilizing a self-aligned polysilicon sidewall spacer technique, a BJT with an ultra-narrow base region is fabricated and tested. Two regimes of operation are identified and characterized under DC conditions. At low base currents, devices exhibited forward current gain as high as betaF = 900. At higher base current values, a transconductance of 59 mS was observed. Microwave scattering parameters were obtained for the BJTs under both biasing conditions and compared to unbiased measurements. Microwave frequency gain was not observed. Instead, bias-dependent non-reciprocal behavior was observed and examined. Limitations associated with the microwave impedance-matched electrode configuration are presented. High current densities in the narrow electrodes cause localized

  10. Nonlinear Optical Functions in Crystalline and Amorphous Silicon-on-Insulator Nanowires

    DEFF Research Database (Denmark)

    Baets, R.; Kuyken, B.; Liu, X.;

    2012-01-01

    Silicon-on-Insulator nanowires provide an excellent platform for nonlinear optical functions in spite of the two-photon absorption at telecom wavelengths. Work on both crystalline and amorphous silicon nanowires is reviewed, in the wavelength range of 1.5 to 2.5 µm.......Silicon-on-Insulator nanowires provide an excellent platform for nonlinear optical functions in spite of the two-photon absorption at telecom wavelengths. Work on both crystalline and amorphous silicon nanowires is reviewed, in the wavelength range of 1.5 to 2.5 µm....

  11. 360° tunable microwave phase shifter based on silicon-on-insulator dual-microring resonator

    DEFF Research Database (Denmark)

    Pu, Minhao; Xue, Weiqi; Liu, Liu; Ou, Haiyan; Yvind, Kresten; Hvam, Jørn Märcher

    2010-01-01

    We demonstrate tunable microwave phase shifters based on electrically tunable silicon-on-insulator dual-microring resonators. A quasi-linear phase shift of 360° with ~2dB radio frequency power variation at a microwave frequency of 40GHz is obtained......We demonstrate tunable microwave phase shifters based on electrically tunable silicon-on-insulator dual-microring resonators. A quasi-linear phase shift of 360° with ~2dB radio frequency power variation at a microwave frequency of 40GHz is obtained...

  12. Breakdown voltage model and structure realization of a thin silicon layer with linear variable doping on a silicon on insulator high voltage device with multiple step field plates

    Institute of Scientific and Technical Information of China (English)

    Qiao Ming; Zhuang Xiang; Wu Li-Juan; Zhang Wen-Tong; Wen Heng-Juan; Zhang Bo; Li Zhao-Ji

    2012-01-01

    Based on the theoretical and experimental investigation of a thin silicon layer (TSL) with linear variable doping (LVD) and further research on the TSL LVD with a multiple step field plate (MSFP),a breakdown voltage (BV) model is proposed and experimentally verified in this paper.With the two-dimensional Poisson equation of the silicon on insulator (SOI) device,the lateral electric field in drift region of the thin silicon layer is assumed to be constant.For the SOI device with LVD in the thin silicon layer,the dependence of the BV on impurity concentration under the drain is investigated by an enhanced dielectric layer field (ENDIF),from which the reduced surface field (RESURF) condition is deduced.The drain in the centre of the device has a good self-isolation effect but the problem of the high voltage interconnection (HVI) line will become serious.The two step field plates including the source field plate and gate field plate can be adopted to shield the HVI adverse effect on the device.Based on this model,the TSL LVD SOI n-channel lateral double-diffused MOSFET (nLDMOS) with MSFP is realized.The experimental breakdown voltage (BV) and specific on-resistance (Ron,sp) of the TSL LVD SOI device are 694 V and 21.3 Ω.mm2 with a drift region length of 60 μm,buried oxide layer of 3 μm,and silicon layer of 0.15 μm,respectively.

  13. Submicrosecond rearrangeable nonblocking silicon-on-insulator thermo-optic 4x4 switch matrix.

    Science.gov (United States)

    Li, Yuntao; Yu, Jinzhong; Chen, Shaowu; Li, Yanping; Chen, Yuanyuan

    2007-03-15

    A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4x4 switch matrix is designed and fabricated. A spot-size converter is integrated to reduce the insertion loss, and a new driving circuit is designed to improve the response speed. The insertion loss is less than 10 dB, and the response time is 950 ns. PMID:17308574

  14. Tunable microwave phase shifter based on silicon-on-insulator microring resonator

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Xue, Weiqi; Ding, Yunhong; Frandsen, Lars Hagedorn; Ou, Haiyan; Yvind, Kresten; Hvam, Jørn Märcher

    2010-01-01

    We demonstrate microwave phase shifters based on electrically tunable silicon-on-insulator microring resonators (MRRs). MRRs with different quality factors are fabricated and tested. A continuously tunable phase shift of up to 336 at a microwave frequency of 40 GHz is obtained using a high...

  15. Investigation of unique total ionizing dose effects in 0.2 µm partially-depleted silicon-on-insulator technology

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, YanWei [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Xiangtan, Hunan 411105 (China); Huang, HuiXiang; Bi, DaWei [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Tang, MingHua, E-mail: mhtang@xtu.edu.cn [Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Xiangtan, Hunan 411105 (China); Zhang, ZhengXuan [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

    2014-05-01

    The total ionizing dose (TID) radiation effects of partially-depleted (PD) silicon-on-insulator (SOI) devices fabricated in a commercial 0.2 µm SOI process were investigated. The experimental results show an original phenomenon: the “ON” irradiation bias configuration is the worst-case bias for both front-gate and back-gate transistors. To understand the mechanism, a charge distribution model is proposed. We consider that the performance degradation of the devices is due to the radiation-induced positive charge trapped in the bottom corner of Shallow Trench Isolation (STI) oxide. In addition, by comparing the irradiation responses of short and long channel devices under different drain biases, the short channel transistors show a larger degeneration of leakage current and threshold voltage. The dipole theory is introduced to explain the TID enhanced short channel effect.

  16. Investigation of unique total ionizing dose effects in 0.2 µm partially-depleted silicon-on-insulator technology

    International Nuclear Information System (INIS)

    The total ionizing dose (TID) radiation effects of partially-depleted (PD) silicon-on-insulator (SOI) devices fabricated in a commercial 0.2 µm SOI process were investigated. The experimental results show an original phenomenon: the “ON” irradiation bias configuration is the worst-case bias for both front-gate and back-gate transistors. To understand the mechanism, a charge distribution model is proposed. We consider that the performance degradation of the devices is due to the radiation-induced positive charge trapped in the bottom corner of Shallow Trench Isolation (STI) oxide. In addition, by comparing the irradiation responses of short and long channel devices under different drain biases, the short channel transistors show a larger degeneration of leakage current and threshold voltage. The dipole theory is introduced to explain the TID enhanced short channel effect

  17. Strain field of a buried oxide aperture

    Science.gov (United States)

    Kießling, F.; Niermann, T.; Lehmann, M.; Schulze, J.-H.; Strittmatter, A.; Schliwa, A.; Pohl, U. W.

    2015-02-01

    The strain field of an AlOx current aperture, fabricated by selective oxidation of an AlAs/GaAs layer buried in a circular GaAs mesa, is studied. Components of the strain tensor for a thin cross-section lamella cut out of such a structure are evaluated from dark-field electron holography, proving the validity of simulations based on linear elasticity. Simulation of the entire structure is utilized to prepare mesa surfaces with tailored strain fields for controlling the nucleation site of InGaAs quantum dots. The experimental proof of strain simulations allows estimating the magnitude of piezoelectricity, yielding for the studied mesa structures a piezoelectric potential up to 50 mV.

  18. Silicon-on-insulator optoelectronic components for micropower solar energy harvesting and bio-environmental instrumentation

    OpenAIRE

    Bulteel, Olivier

    2011-01-01

    This work presents an analysis of optoelectronic components fabricated in silicon-on-insulator (SOI) technology. On one hand, the thesis focuses on UV sensors (λ < 400nm) for bio-environmental applications and on the other hand, it studies CMOS integrated photovoltaic cells for micropower solar energy harvesting. The SOI technology features a thin Si film into which lateral PIN photodiodes are optimized. The responsivity is modeled to optimize the spectral response in UV by adequate choice...

  19. Design and Optimization of Polarization Splitting and Rotating Devices in Silicon-on-Insulator Technology

    Directory of Open Access Journals (Sweden)

    Benedetto Troia

    2014-01-01

    Full Text Available We review polarization splitting and rotating photonic devices based on silicon-on-insulator technology platform, focusing on their performance and design criteria. In addition, we present a theoretical investigation and optimization of some rotator and splitter architectures to be employed for polarization diversity circuits. In this context, fabrication tolerances and their influences on device performance are theoretically estimated by rigorous simulations too.

  20. Ultracompact polarization converter with a dual subwavelength trench built in a silicon-on-insulator waveguide

    OpenAIRE

    Villafranca Velasco, Aitor; Calvo Padilla, María Luisa; Cheben, Pavel; Ortega Moñux, Alejandro; Alonso Ramos, Carlos Alberto; Molina Fernández, Íñigo; Lapointe, Jean; Vachon, Martin; Janz, Siegfried; Xu, Dan-Xia

    2012-01-01

    The design and fabrication of an ultracompact silicon-on-insulator polarization converter is reported. The polarization conversion with an extinction ratio of 16 dB is achieved for a conversion length of only 10 mu m. Polarization rotation is achieved by inducing a vertical asymmetry by forming in the waveguide core two subwavelength trenches of different depths. By taking advantage of the calibrated reactive ion etch lag, the two depths are implemented using a single mask and etching process...

  1. Embedded ultrasound sensor in a silicon-on-insulator photonic platform

    International Nuclear Information System (INIS)

    A miniaturized ultrasound sensor is demonstrated in a silicon-on-insulator platform. The sensor is based on a π-phase-shifted Bragg grating formed by waveguide corrugation. Ultrasound detection is performed by monitoring shifts in the resonance frequency of the grating using pulse interferometry. The device is characterized by measuring its response to a wideband acoustic point source generated using the optoacoustic effect. Experimental results show that the sensor's response is dominated by the formation of surface acoustic waves

  2. Laser ablation- and plasma etching-based patterning of graphene on silicon-on-insulator waveguides

    OpenAIRE

    Van Erps, Jurgen; Ciuk, Tymoteusz; Pasternak, Iwona; Krajewska, Aleksandra; Strupinski, Wlodek; Put, Steven; Van Steenberge, Geert; Baert, Kitty; Terryn, Herman; Thienpont, Hugo; Vermeulen, Nathalie

    2015-01-01

    We present a new approach to remove monolayer graphene transferred on top of a silicon-on-insulator (SOI) photonic integrated chip. Femtosecond laser ablation is used for the first time to remove graphene from SOI waveguides, whereas oxygen plasma etching through a metal mask is employed to peel off graphene from the grating couplers attached to the waveguides. We show by means of Raman spectroscopy and atomic force microscopy that the removal of graphene is successful with minimal damage to ...

  3. Saturation effects in femtosecond laser ablation of silicon-on-insulator

    OpenAIRE

    Zhang, H.; van Oosten, D.; Krol, D.M.; Dijkhuis, J.I.

    2011-01-01

    We report a surface morphology study on single-shot submicron features fabricated on silicon on insulator by tightly focused femtosecond laser pulses. In the regime just below single-shot ablation threshold nano-tips are formed, whereas in the regime just above single-shot ablation threshold, a saturation in the ablation depth is found. We attribute this saturation by secondary laser absorption in the laser-induced plasma. In this regime, we find excellent agreement between the measured depth...

  4. Integrated spectrometer and integrated detectors on silicon-on-insulator for short-wave infrared applications

    OpenAIRE

    Ryckeboer, Eva; Gassenq, Alban; Hattasan, Nannicha; Kuyken, Bart; Cerutti, Laurent; Rodriguez, Jean-Baptiste; Tournie, Eric; Roelkens, Gunther; Bogaerts, Wim; Baets, Roel

    2012-01-01

    We present a miniature spectrometer fabricated on a Silicon-on-Insulator substrate with center wavelength at 2.15 mu m. The spectrometer is a planar concave grating (PCG) with 6 channels and 4 nm channel spacing with a crosstalk of -12 dB. We investigate heterogeneously integrated grating-assisted GaInAsSb photodiodes for future implementation as detector array.

  5. Optical MEMS based on silicon-on-insulator (SOI) for monolithic microoptics

    OpenAIRE

    Noell, Wilfried; Sun, Winston; de Rooij, Nicolaas F.; Herzig, Hans-Peter; Manzardo, Omar; Dändliker, René

    2007-01-01

    Microelectromechanical systems (MEMS) combined with optical components add optical functionality to devices and lead to the terms optical MEMS or MOEMS. The underlying technology of the presented devices is silicon-on-insulator (SOI) based batch fabrication, which delivers small, reliable and lasting monolithic bulk silicon structures for commercial devices with the advantage of being very insensitive to temperature changes. The particular strength of the technology is monolithic horizontal a...

  6. Large current MOSFET on photonic silicon-on-insulator wafers and its monolithic integration with a thermo-optic 2 × 2 Mach-Zehnder switch.

    Science.gov (United States)

    Cong, G W; Matsukawa, T; Chiba, T; Tadokoro, H; Yanagihara, M; Ohno, M; Kawashima, H; Kuwatsuka, H; Igarashi, Y; Masahara, M; Ishikawa, H

    2013-03-25

    n-channel body-tied partially depleted metal-oxide-semiconductor field-effect transistors (MOSFETs) were fabricated for large current applications on a silicon-on-insulator wafer with photonics-oriented specifications. The MOSFET can drive an electrical current as large as 20 mA. We monolithically integrated this MOSFET with a 2 × 2 Mach-Zehnder interferometer optical switch having thermo-optic phase shifters. The static and dynamic performances of the integrated device are experimentally evaluated. PMID:23546071

  7. High temperature study of flexible silicon-on-insulator fin field-effect transistors

    KAUST Repository

    Diab, Amer

    2014-09-29

    We report high temperature electrical transport characteristics of a flexible version of the semiconductor industry\\'s most advanced architecture: fin field-effect transistor on silicon-on-insulator with sub-20 nm fins and high-κ/metal gate stacks. Characterization from room to high temperature (150 °C) was completed to determine temperature dependence of drain current (Ids), gate leakage current (Igs), transconductance (gm), and extracted low-field mobility (μ0). Mobility degradation with temperature is mainly caused by phonon scattering. The other device characteristics show insignificant difference at high temperature which proves the suitability of inorganic flexible electronics with advanced device architecture.

  8. Guided acoustic and optical waves in silicon-on-insulator for Brillouin scattering and optomechanics

    CERN Document Server

    Sarabalis, Christopher J; Safavi-Naeini, Amir H

    2016-01-01

    We numerically study silicon waveguides on silica showing that it is possible to simultaneously guide optical and acoustic waves in the technologically important silicon on insulator (SOI) material system. Thin waveguides, or fins, exhibit geometrically softened mechanical modes at gigahertz frequencies with phase velocities below the Rayleigh velocity in glass, eliminating acoustic radiation losses. We propose slot waveguides on glass with telecom optical frequencies and strong radiation pressure forces resulting in Brillouin gains on the order of 500 and 50,000 1/(Wm) for backward and forward Brillouin scattering, respectively.

  9. Implantation of oxygen ions for the realization of SOS (silicon on insulator) structures: SIMOX

    International Nuclear Information System (INIS)

    Highdose oxygen implantation is becoming a serious candidate for SOI (silicon on insulator) structure realization. The fabrication condition study of these substrates allowed to show up the implantation and annealing parameter importance for microstructure, and particularly for crystal quality of silicon films. It has been shown that the use of high temperature annealings leads to high quality substrates: monocrystal silicon film without any precipitate, at the card scale; Si/Si O2 interface formation. After annealing at 1340OC, Hall mobilities have been measured in silicon film, and its residual doping is very low. First characteristics and performance of submicron CMOS circuits prooves the electric quality of these substrates

  10. Ultracompact polarization converter with a dual subwavelength trench built in a silicon-on-insulator waveguide.

    Science.gov (United States)

    Velasco, Aitor V; Calvo, María L; Cheben, Pavel; Ortega-Moñux, Alejandro; Schmid, Jens H; Ramos, Carlos Alonso; Fernandez, Iñigo Molina; Lapointe, Jean; Vachon, Martin; Janz, Siegfried; Xu, Dan-Xia

    2012-02-01

    The design and fabrication of an ultracompact silicon-on-insulator polarization converter is reported. The polarization conversion with an extinction ratio of 16 dB is achieved for a conversion length of only 10 μm. Polarization rotation is achieved by inducing a vertical asymmetry by forming in the waveguide core two subwavelength trenches of different depths. By taking advantage of the calibrated reactive ion etch lag, the two depths are implemented using a single mask and etching process. The measured converter loss is -0.7 dB and the 3 dB bandwidth is 26 nm. PMID:22297354

  11. Silicon-on-Insulator Based Electro-optic Variable Optical Attenuator with a Series Structure

    Institute of Scientific and Technical Information of China (English)

    HE Yue-Jiao; LI Fang; LIU Yu-Liang

    2005-01-01

    An electro-optic variable optical attenuator in silicon-on-insulator is designed and fabricated. A series structure is used to improve the device efficiency. Compared to the attenuator in the single p-i-n diode structure in the same modulating length, the attenuation range of the device in the series structure improves 2-3 times in the same injecting current density, while the insertion loss is not affected. The maximum dynamic attenuation of the device is greater than 30dB. The response frequency is obtained to be about 2MHz.

  12. High-Q silicon-on-insulator slot photonic crystal cavity infiltrated by a liquid

    International Nuclear Information System (INIS)

    We report the experimental realization of a high-Q slot photonic crystal cavity in Silicon-On-Insulator (SOI) configuration infiltrated by a liquid. Loaded Q-factor of 23 000 is measured at telecom wavelength. The intrinsic quality factor inferred from the transmission spectrum is higher than 200 000, which represents a record value for slot photonic crystal cavities on SOI, whereas the maximum of intensity of the cavity is roughly equal to 20% of the light transmitted in the waveguide. This result makes filled slot photonic crystal cavities very promising for silicon-based light emission and ultrafast nonlinear optics

  13. A large bandwidth photonic delay line using passive cascaded silicon-on-insulator microring resonators

    International Nuclear Information System (INIS)

    This paper investigated the design and the characterization of a photonic delay line based on passive cascaded silicon-on-insulator (SOI) microrings. We considered the compromise of group delay, bandwidth and insertion loss. A 3-stage double channel side-coupled integrated spaced sequence of resonator (SCISSOR) device was optimized by shifting the resonance of each microring and fabricated with electron beam lithography and dry etching. The group delay was measured to be 17 ps for non-return-to-zero signals at different bit rates and the bandwidth of 78 GHz was achieved. The experiment result agreed well with our simulation. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  14. Fabrication of Thermo-Optic Switch in Silicon-on-Insulator

    Institute of Scientific and Technical Information of China (English)

    王章涛; 夏金松; 樊中朝; 陈少武; 余金中

    2003-01-01

    Silicon-on-insulator technology has been used to fabricate 2 × 2 thermo-optic switches. The switch shows crosstalk of-23.4 dB and extinction ratio of 18.1 dB in the bar-state. The switching speed is less than 30 μs and the power consumption is about 420mW. The measured excess loss is 1.8 dB. These merits make the switch more attractive for applications in wavelength division multiplexing.

  15. Widely tunable microwave phase shifter based on silicon-on-insulator dual-microring resonator

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Xue, Weiqi; Ding, Yunhong; Ou, Haiyan; Yvind, Kresten; Hvam, Jørn Märcher

    2010-01-01

    We propose and demonstrate tunable microwave phase shifters based on electrically tunable silicon-on-insulator microring resonators. The phase-shifting range and the RF-power variation are analyzed. A maximum phase-shifting range of 0~600° is achieved by utilizing a dual-microring resonator. A...... quasi-linear phase shift of 360° with RF-power variation lower than 2dB and a continuous 270° phase shift without RF-power variation at a microwave frequency of 40GHz are also demonstrated....

  16. Microdisk enhanced photodetector based on Ge self-assembled quantum dots on silicon-on-insulator

    International Nuclear Information System (INIS)

    By embedding Ge self-assembled quantum dots (QDs) in microdisk cavity, resonant-cavity-enhanced waveguide photodetector (PD) with ultra-low dark current and high responsivity is experimentally demonstrated around 1.55 μm wavelength. Ge QDs are grown on silicon-on-insulator substrate by solid-source molecular beam epitaxy. Microdisk is used to enhance the absorption efficiency of Ge QDs, and a vertical PIN diode is integrated with the microdisk to extract photo-generated current. The dark current density of our PD is as low as 0.97 mA/cm2 under − 10 V bias. At resonant wavelength of 1541.15 nm, enhanced peak responsivity of 2.13 mA/W is obtained. The wavelength selectivity of the microdisk PD also makes it preferable for wavelength-division multiplexing optical receiver. - Highlights: • We demonstrated microdisk enhanced photodetector based on Ge quantum dots (QDs). • Ge QDs were grown on silicon-on-insulator by molecular beam epitaxy. • Ultra-low dark current and high peak responsivity were obtained around 1.55 μm. • The photodetector (PD) showed good wavelength selectivity. • The PD is preferable for wavelength-division multiplexing optical receiver

  17. Microdisk enhanced photodetector based on Ge self-assembled quantum dots on silicon-on-insulator

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xuejun, E-mail: xxu@tcu.ac.jp; Chiba, Taichi; Maruizumi, Takuya; Shiraki, Yasuhiro

    2014-04-30

    By embedding Ge self-assembled quantum dots (QDs) in microdisk cavity, resonant-cavity-enhanced waveguide photodetector (PD) with ultra-low dark current and high responsivity is experimentally demonstrated around 1.55 μm wavelength. Ge QDs are grown on silicon-on-insulator substrate by solid-source molecular beam epitaxy. Microdisk is used to enhance the absorption efficiency of Ge QDs, and a vertical PIN diode is integrated with the microdisk to extract photo-generated current. The dark current density of our PD is as low as 0.97 mA/cm{sup 2} under − 10 V bias. At resonant wavelength of 1541.15 nm, enhanced peak responsivity of 2.13 mA/W is obtained. The wavelength selectivity of the microdisk PD also makes it preferable for wavelength-division multiplexing optical receiver. - Highlights: • We demonstrated microdisk enhanced photodetector based on Ge quantum dots (QDs). • Ge QDs were grown on silicon-on-insulator by molecular beam epitaxy. • Ultra-low dark current and high peak responsivity were obtained around 1.55 μm. • The photodetector (PD) showed good wavelength selectivity. • The PD is preferable for wavelength-division multiplexing optical receiver.

  18. Investigation of negative bias temperature instability dependence on fin width of silicon-on-insulator-fin-based field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Young, Chadwin D., E-mail: chadwin.young@utdallas.edu; Wang, Zhe [Materials Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, Texas 75080 (United States); Neugroschel, Arnost [Department of Electrical and Computer Enginering, University of Florida, Gainesville, Florida 32611 (United States); Majumdar, Kausik; Matthews, Ken; Hobbs, Chris [SEMATECH, Albany, New York 12203 (United States)

    2015-01-21

    The fin width dependence of negative bias temperature instability (NBTI) of double-gate, fin-based p-type Field Effect Transistors (FinFETs) fabricated on silicon-on-insulator (SOI) wafers was investigated. The NBTI degradation increased as the fin width narrowed. To investigate this phenomenon, simulations of pre-stress conditions were employed to determine any differences in gate oxide field, fin band bending, and electric field profile as a function of the fin width. The simulation results were similar at a given gate stress bias, regardless of the fin width, although the threshold voltage was found to increase with decreasing fin width. Thus, the NBTI fin width dependence could not be explained from the pre-stress conditions. Different physics-based degradation models were evaluated using specific fin-based device structures with different biasing schemes to ascertain an appropriate model that best explains the measured NBTI dependence. A plausible cause is an accumulation of electrons that tunnel from the gate during stress into the floating SOI fin body. As the fin narrows, the sidewall device channel moves in closer proximity to the stored electrons, thereby inducing more band bending at the fin/dielectric interface, resulting in a higher electric field and hole concentration in this region during stress, which leads to more degradation. The data obtained in this work provide direct experimental proof of the effect of electron accumulation on the threshold voltage stability in FinFETs.

  19. Fabrication of Si-based planar type patch clamp biosensor using silicon on insulator substrate

    International Nuclear Information System (INIS)

    The aim of this paper is to fabricate the planar type patch clamp ion-channel biosensor, which is suitable for the high throughput screening, using silicon-on-insulator (SOI) substrate. The micropore with 1.2 μm diameter is formed through the top Si layer and the SiO2 box layer of the SOI substrate by focused ion beam (FIB). Then the substrate is assembled into the microfluidic circuit. The human embryonic kidney 293 (HEK-293) cell transfected with transient receptor potential vanilloid type 1 (TRPV1) is positioned on the micropore and the whole-cell configuration is formed by the suction. Capsaicin is added to the extracellular solution as a ligand molecule, and the channel current showing the desensitization unique to TRPV1 is measured successfully

  20. Fabrication of Si-based planar type patch clamp biosensor using silicon on insulator substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.L.; Asano, T. [Graduate University for Advanced Studies, Myodaiji, Okazaki, 444-8585 (Japan); Uno, H. [Institute for Molecular Science, Myodaiji, Okazaki, 444-8585 (Japan); Tero, R. [Graduate University for Advanced Studies, Myodaiji, Okazaki, 444-8585 (Japan); Institute for Molecular Science, Myodaiji, Okazaki, 444-8585 (Japan); Suzui, M.; Nakao, S. [Institute for Molecular Science, Myodaiji, Okazaki, 444-8585 (Japan); Kaito, T. [SII NanoTechnology Inc., 36-1, Takenoshita, Oyama-cho, Sunto-gun, Shizuoka, 410-1393 (Japan); Shibasaki, K.; Tominaga, M. [Okazaki Institute for Integrative Bioscience, 5-1, Higashiyama, Myodaiji, Okazaki, 444-8787 (Japan); Utsumi, Y. [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 3-1-2, Koto, Kamigori, Ako-gun, Hyogo, 678-1205 (Japan); Gao, Y.L. [Department of Physics and Astronomy, Rochester University, Rochester, New York 14627 (United States); Urisu, T. [Graduate University for Advanced Studies, Myodaiji, Okazaki, 444-8585 (Japan); Institute for Molecular Science, Myodaiji, Okazaki, 444-8585 (Japan)], E-mail: urisu@ims.ac.jp

    2008-03-03

    The aim of this paper is to fabricate the planar type patch clamp ion-channel biosensor, which is suitable for the high throughput screening, using silicon-on-insulator (SOI) substrate. The micropore with 1.2 {mu}m diameter is formed through the top Si layer and the SiO{sub 2} box layer of the SOI substrate by focused ion beam (FIB). Then the substrate is assembled into the microfluidic circuit. The human embryonic kidney 293 (HEK-293) cell transfected with transient receptor potential vanilloid type 1 (TRPV1) is positioned on the micropore and the whole-cell configuration is formed by the suction. Capsaicin is added to the extracellular solution as a ligand molecule, and the channel current showing the desensitization unique to TRPV1 is measured successfully.

  1. All-optical switching in silicon-on-insulator photonic wire nano-cavities.

    Science.gov (United States)

    Belotti, Michele; Galli, Matteo; Gerace, Dario; Andreani, Lucio Claudio; Guizzetti, Giorgio; Md Zain, Ahmad R; Johnson, Nigel P; Sorel, Marc; De La Rue, Richard M

    2010-01-18

    We report on experimental demonstration of all-optical switching in a silicon-on-insulator photonic wire nanocavity operating at telecom wavelengths. The switching is performed with a control pulse energy as low as approximately 0.1 pJ on a cavity device that presents very high signal transmission, an ultra-high quality-factor, almost diffraction-limited modal volume and a footprint of only 5 microm(2). High-speed modulation of the cavity mode is achieved by means of optical injection of free carriers using a nanosecond pulsed laser. Experimental results are interpreted by means of finite-difference time-domain simulations. The possibility of using this device as a logic gate is also demonstrated. PMID:20173973

  2. Impact of Free Carriers on Modulational Instability in Silicon-on-insulator Nanowaveguides

    CERN Document Server

    Chaturvedi, Deepa

    2016-01-01

    We have numerically studied the effect of free-carrier-induced loss and dispersion on the modulational instability (MI) gain at low input powers in silicon-on-insulator (SOI) nanowaveguides with normal and anomalous second-order dispersion. We have shown that the free carriers affect the gain spectra even at low input powers. First time we have reported the gain in normal SOI nanowaveguides even in the absence of higher order dispersion parameters, which is due to the interaction of free-carrier-induced dispersion and nonlinearity. The MI gain in an anomalous SOI nanowaveguide vanishes even at a few milliwatt range of input power due to this interaction. We have shown that the gain could be achieved in an anomalous nanowaveguides by reducing the free carrier lifetime.

  3. Early effect modeling of silicon-on-insulator SiGe heterojunction bipolar transistors

    Institute of Scientific and Technical Information of China (English)

    Xu Xiao-Bo; Zhang He-Ming; Hu Hui-Yong; Ma Jian-Li

    2011-01-01

    Silicon germanium (SiGe) heterojunction bipolar transistor (HBT) on thin silicon-on-insulator (SOI) has recently been demonstrated and integrated into the latest SOI BiCMOS technology. The Early effect of the SOI SiGe HBT is analysed considering vertical and horizontal collector depletion, which is different from that of a bulk counterpart. A new compact formula of the Early voltage is presented and validated by an ISE TCAD simulation. The Early voltage shows a kink with the increase of the reverse base-collector bias. Large differences are observed between SOI devices and their bulk counterparts. The presented Early effect model can be employed for a fast evaluation of the Early voltage and is useful to the design, the simulation and the fabrication of high performance SOI SiGe devices and circuits.

  4. A ministop band in a single-defect photonic crystal waveguide based on silicon on insulator

    International Nuclear Information System (INIS)

    This paper reports that a two-dimensional single-defect photonic crystal waveguide in the Γ-K direction with triangular lattice on a silicon-on-insulator substrate is fabricated by the combination of electron beam lithography and inductively coupled plasma etching. A ministop band (MSB) is observed by the measurement of transmission characteristics. It results from the coupling between the two modes with the same symmetry, which is analysed from the stimulated band diagram by the effective index and the two-dimensional plane wave expansion methods. The parameter working on the MSB is the ratio of the radius of air holes to the lattice constant, r/a. It is obtained that the critical r/a value determining the occurrence or disappearance of MSB is 0.36. When r/a is larger than or equal to 0.36, the MSB occurs. However, when r/a is smaller than 0.36, the MSB disappears

  5. Development of the Pixelated Photon Detector Using Silicon on Insulator Technology for TOF-PET

    CERN Document Server

    Koyama, Akihiro; Takahashi, Hiroyuki; Orita, Tadashi; Arai, Yasuo; Kurachi, Ikuo; Miyoshi, Toshinobu; Nio, Daisuke; Hamasaki, Ryutaro

    2015-01-01

    To measure light emission pattern in scintillator, higher sensitivity and faster response are required to photo detector. Such as single photon avalanche diode (SPAD), conventional pixelated photo detector is operated at Geiger avalanche multiplication. However higher gain of SPAD seems very attractive, photon detection efficiency per unit area is low. This weak point is mainly caused by Geiger avalanche mechanism. To overcome these difficulties, we designed Pixelated Linear Avalanche Integration Detector using Silicon on Insulator technology (SOI-Plaid). To avoid dark count noise and dead time comes from quench circuit, we are planning to use APD in linear multiplication mode. SOI technology enables laminating readout circuit and APD layer, and high-speed and low-noise signal reading regardless smaller gain of linear APD. This study shows design of linear APD by using SOI fabrication process. We designed test element group (TEG) of linear APD and inspected optimal structure of linear APD.

  6. Ultracompact silicon-on-insulator polarization rotator for polarization-diversified circuits.

    Science.gov (United States)

    Guan, Hang; Ma, Yangjin; Shi, Ruizhi; Novack, Ari; Tao, Jingcheng; Fang, Qing; Lim, Andy Eu-Jin; Lo, Guo-Qiang; Baehr-Jones, Tom; Hochberg, Michael

    2014-08-15

    We present an ultracompact (15.3 μm long) and high-efficiency silicon-on-insulator polarization rotator designed for polarization-diversified circuits. The rotator is comprised of a bilevel-tapered TM0-to-TE1 mode converter and a novel bent-tapered TE1-to-TE0 mode converter. The rotator has a simulated polarization conversion loss lower than 0.2 dB and a polarization-extinction ratio larger than 25 dB over a wavelength range of 80 nm around 1550 nm. The rotator has a SiO2 top-cladding and can be fabricated in a CMOS-compatible process. PMID:25121853

  7. Vertical optical ring resonators fully integrated with nanophotonic waveguides on silicon-on-insulator substrates

    CERN Document Server

    Madani, Abbas; Stolarek, David; Zimmermann, Lars; Ma, Libo; Schmidt, Oliver G

    2015-01-01

    We demonstrate full integration of vertical optical ring resonators with silicon nanophotonic waveguides on silicon-on-insulator substrates to accomplish a significant step towards 3D photonic integration. The on-chip integration is realized by rolling up 2D differentially strained TiO2 nanomembranes into 3D microtube cavities on a nanophotonic microchip. The integration configuration allows for out of plane optical coupling between the in-plane nanowaveguides and the vertical microtube cavities as a compact and mechanically stable optical unit, which could enable refined vertical light transfer in 3D stacks of multiple photonic layers. In this vertical transmission scheme, resonant filtering of optical signals at telecommunication wavelengths is demonstrated based on subwavelength thick walled microcavities. Moreover, an array of microtube cavities is prepared and each microtube cavity is integrated with multiple waveguides which opens up interesting perspectives towards parallel and multi-routing through a ...

  8. Laser ablation- and plasma etching-based patterning of graphene on silicon-on-insulator waveguides.

    Science.gov (United States)

    Van Erps, Jürgen; Ciuk, Tymoteusz; Pasternak, Iwona; Krajewska, Aleksandra; Strupinski, Wlodek; Van Put, Steven; Van Steenberge, Geert; Baert, Kitty; Terryn, Herman; Thienpont, Hugo; Vermeulen, Nathalie

    2015-10-01

    We present a new approach to remove monolayer graphene transferred on top of a silicon-on-insulator (SOI) photonic integrated chip. Femtosecond laser ablation is used for the first time to remove graphene from SOI waveguides, whereas oxygen plasma etching through a metal mask is employed to peel off graphene from the grating couplers attached to the waveguides. We show by means of Raman spectroscopy and atomic force microscopy that the removal of graphene is successful with minimal damage to the underlying SOI waveguides. Finally, we employ both removal techniques to measure the contribution of graphene to the loss of grating-coupled graphene-covered SOI waveguides using the cut-back method. PMID:26480176

  9. Planar Fully-Depleted-Silicon-On-Insulator technologies: Toward the 28 nm node and beyond

    Science.gov (United States)

    Doris, B.; DeSalvo, B.; Cheng, K.; Morin, P.; Vinet, M.

    2016-03-01

    This paper presents a comprehensive overview of the research done in the last decade on planar Fully-Depleted-Silicon-On-Insulator (FDSOI) technologies in the frame of the joint development program between IBM, ST Microelectronics and CEA-LETI. In particular, we review the technological developments ranging from substrate engineering to process modules that enable functionality and improve FDSOI performance over several generations. Various multi Vt integration schemes to maximize the benefits of the thin BOX FDSOI platform are discussed. Manufacturability as well as scalability concerns are highlighted and addressed. In addition, this work provides understanding of the performance/power trade-offs for FDSOI circuits and device variability. Finally, clear directions for future application-specific products are given, demonstrating that FDSOI is an attractive CMOS option for next generation high performance and low-power applications.

  10. Analytical modeling and simulation of germanium single gate silicon on insulator TFET

    International Nuclear Information System (INIS)

    This paper proposes a new two dimensional (2D) analytical model for a germanium (Ge) single gate silicon-on-insulator tunnel field effect transistor (SG SOI TFET). The parabolic approximation technique is used to solve the 2D Poisson equation with suitable boundary conditions and analytical expressions are derived for the surface potential, the electric field along the channel and the vertical electric field. The device output tunnelling current is derived further by using the electric fields. The results show that Ge based TFETs have significant improvements in on-current characteristics. The effectiveness of the proposed model has been verified by comparing the analytical model results with the technology computer aided design (TCAD) simulation results and also comparing them with results from a silicon based TFET. (semiconductor devices)

  11. Hot-Electron Bolometer Mixers on Silicon-on-Insulator Substrates for Terahertz Frequencies

    Science.gov (United States)

    Skalare, Anders; Stern, Jeffrey; Bumble, Bruce; Maiwald, Frank

    2005-01-01

    A terahertz Hot-Electron Bolometer (HEB) mixer design using device substrates based on Silicon-On-Insulator (SOI) technology is described. This substrate technology allows very thin chips (6 pm) with almost arbitrary shape to be manufactured, so that they can be tightly fitted into a waveguide structure and operated at very high frequencies with only low risk for power leakages and resonance modes. The NbTiN-based bolometers are contacted by gold beam-leads, while other beamleads are used to hold the chip in place in the waveguide test fixture. The initial tests yielded an equivalent receiver noise temperature of 3460 K double-sideband at a local oscillator frequency of 1.462 THz and an intermediate frequency of 1.4 GHz.

  12. High-efficiency, large-bandwidth silicon-on-insulator grating coupler based on a fully-etched photonic crystal structure

    DEFF Research Database (Denmark)

    Liu, Liu; Pu, Minhao; Yvind, Kresten; Hvam, Jørn Märcher

    2010-01-01

    A grating coupler for interfacing between single-mode fibers and photonic circuits on silicon-on-insulator is demonstrated. It consists of columns of fully etched photonic crystal holes, which are made in the same lithography and etching processes used for making the silicon-on-insulator wire...

  13. Optical microcavities based on surface modes in two-dimensional photonic crystals and silicon-on-insulator photonic crystals

    DEFF Research Database (Denmark)

    Xiao, Sanshui; Qiu, M.

    2007-01-01

    Surface-mode optical microcavities based on two-dimensional photonic crystals and silicon-on-insulator photonic crystals are studied. We demonstrate that a high-quality-factor microcavity can be easily realized in these structures. With an increasing of the cavity length, the quality factor is gr...

  14. Mechanism of floating body effect mitigation via cutting off source injection in a fully-depleted silicon-on-insulator technology

    Science.gov (United States)

    Pengcheng, Huang; Shuming, Chen; Jianjun, Chen

    2016-03-01

    In this paper, the effect of floating body effect (FBE) on a single event transient generation mechanism in fully depleted (FD) silicon-on-insulator (SOI) technology is investigated using three-dimensional technology computer-aided design (3D-TCAD) numerical simulation. The results indicate that the main SET generation mechanism is not carrier drift/diffusion but floating body effect (FBE) whether for positive or negative channel metal oxide semiconductor (PMOS or NMOS). Two stacking layout designs mitigating FBE are investigated as well, and the results indicate that the in-line stacking (IS) layout can mitigate FBE completely and is area penalty saving compared with the conventional stacking layout. Project supported by the National Natural Science Foundation of China (Grant Nos. 61376109, 61434007, and 61176030) and the Advanced Research Project of National University of Defense Technology, China (Grant No. 0100066314001).

  15. Modeling and experimental investigation of an integrated optical microheater in silicon-on-insulator.

    Science.gov (United States)

    Kaushal, Saket; Das, Bijoy Krishna

    2016-04-10

    A linear piecewise model has been formulated to analyze the performance of a metallic microheater integrated with single-mode waveguides (λ∼1550  nm) in silicon-on-insulator (SOI). The model has been used to evaluate integrated optical microheaters fabricated in a SOI substrate with 2 µm device layer thickness. The Fabry-Perot modulation technique has been used to extract the effective thermo-optic phase shift and response time. The effective thermal power budget of Peff,π∼500  µW (out of actually consumed power Pπ=1.1  mW) for a π phase shift and a switching time of τ∼9  µs, have been recorded for a typical Ti heater stripe of length LH=50  µm, width WH=2  µm, and thickness tH∼150  nm, integrated with a Fabry-Perot waveguide cavity of length ∼20  mm. It has been shown that the performance of a heater improves (in terms of power budget) as the length of a microheater decreases. However, smaller heater size requires higher joule heating to obtain a desired phase shift, which is again found to be dependent on polarization of the guided mode because of thermal stress. PMID:27139842

  16. Vertical optical ring resonators fully integrated with nanophotonic waveguides on silicon-on-insulator substrates

    Science.gov (United States)

    Madani, Abbas; Kleinert, Moritz; Stolarek, David; Zimmermann, Lars; Ma, Libo; Schmidt, Oliver G.

    2015-08-01

    We demonstrate full integration of vertical optical ring resonators with silicon nanophotonic waveguides on silicon-on-insulator substrates to accomplish a significant step towards 3D photonic integration. The on-chip integration is realized by rolling up 2D differentially strained TiO2 nanomembranes into 3D microtube cavities on a nanophotonic microchip. The integration configuration allows for out of plane optical coupling between the in-plane nanowaveguides and the vertical microtube cavities as a compact and mechanically stable optical unit, which could enable refined vertical light transfer in 3D stacks of multiple photonic layers. In this vertical transmission scheme, resonant filtering of optical signals at telecommunication wavelengths is demonstrated based on subwavelength thick walled microcavities. Moreover, an array of microtube cavities is prepared and each microtube cavity is integrated with multiple waveguides which opens up interesting perspectives towards parallel and multi-routing through a single cavity device as well as high-throughput optofluidic sensing schemes.

  17. Tunable spiral Bragg gratings in 60-nm-thick silicon-on-insulator strip waveguides.

    Science.gov (United States)

    Zou, Zhi; Zhou, Linjie; Wang, Minjuan; Wu, Kan; Chen, Jianping

    2016-06-13

    We demonstrate spiral integrated Bragg gratings (IBGs) in 60-nm-thick strip waveguides on the silicon-on-insulator (SOI) platform. The length of the spiral IBG is 2 mm, occupying an area of 147 × 141 μm2 with a minimum bending radius of 20 μm. Experiments show that the spiral IBGs exhibit a single narrow transparent peak with a Q-factor of 1 × 105 in a broad stopband, induced by the phase shift of the S-junction at the spiral center. This phenomenon is analogous to the electromagnetically induced transparency (EIT) effect. The transparent peak can periodically shift in the stopband upon heating of the S-junction using a TiN-based heater on top. The peak transmittance and Q-factor are dependent on the reflectivity of the spiral IBG. The transparent peak can be completely eliminated under a certain tuning power, and the spiral IBG hence behaves as a bandstop optical filter. The bandwidth is 0.94 nm and the extinction ratio is as high as 43 dB. The stopband can also be shifted by heating the Bragg gratings using a separate TiN heater. The experimental results agree well with the modeling results based on the transfer matrix method. PMID:27410302

  18. Mode hybridization and conversion in silicon-on-insulator nanowires with angled sidewalls.

    Science.gov (United States)

    Dai, Daoxin; Zhang, Ming

    2015-12-14

    The mode property and light propagation in a tapered silicon-on-insulator (SOI) nanowire with angled sidewalls is analyzed. Mode hybridization is observed and mode conversion between the TM fundamental mode and higher-order TE modes happens when light propagates in a waveguide taper which is used very often in the design of photonic integrated devices. This mode conversion ratio is possible to be very high (even close to 100%) when the taper is long enough to be adiabatic, which might be useful for some applications of multimode photonics. When the mode conversion is undesired to avoid any excess loss as well as crosstalk for photonic integrated circuits, one can depress the mode conversion by compensating the vertical asymmetry in the way of reducing the sidewall angle or introducing an optimal refractive index for the upper-cladding. It is also possible to eliminate the undesired mode conversion almost and improve the desired mode conversion greatly by introducing an abrupt junction connecting two sections with different widths to jump over the mode hybridization region. PMID:26699034

  19. Adiabatic Nanofocusing in Hybrid Gap Plasmon Waveguides on the Silicon-on-Insulator Platform.

    Science.gov (United States)

    Nielsen, Michael P; Lafone, Lucas; Rakovich, Aliaksandra; Sidiropoulos, Themistoklis P H; Rahmani, Mohsen; Maier, Stefan A; Oulton, Rupert F

    2016-02-10

    We present an experimental demonstration of a new class of hybrid gap plasmon waveguides on the silicon-on-insulator (SOI) platform. Created by the hybridization of the plasmonic mode of a gap in a thin metal sheet and the transverse-electric (TE) photonic mode of an SOI slab, this waveguide is designed for efficient adiabatic nanofocusing simply by varying the gap width. For gap widths greater than 100 nm, the mode is primarily photonic in character and propagation lengths can be many tens of micrometers. For gap widths below 100 nm, the mode becomes plasmonic in character with field confinement predominantly within the gap region and with propagation lengths of a few microns. We estimate the electric field intensity enhancement in hybrid gap plasmon waveguide tapers at 1550 nm by three-photon absorption of selectively deposited CdSe/ZnS quantum dots within the gap. Here, we show electric field intensity enhancements of up to 167 ± 26 for a 24 nm gap, proving the viability of low loss adiabatic nanofocusing on a commercially relevant photonics platform. PMID:26771836

  20. A Temperature Sensor using a Silicon-on-Insulator (SOI) Timer for Very Wide Temperature Measurement

    Science.gov (United States)

    Patterson, Richard L.; Hammoud, Ahmad; Elbuluk, Malik; Culley, Dennis E.

    2008-01-01

    A temperature sensor based on a commercial-off-the-shelf (COTS) Silicon-on-Insulator (SOI) Timer was designed for extreme temperature applications. The sensor can operate under a wide temperature range from hot jet engine compartments to cryogenic space exploration missions. For example, in Jet Engine Distributed Control Architecture, the sensor must be able to operate at temperatures exceeding 150 C. For space missions, extremely low cryogenic temperatures need to be measured. The output of the sensor, which consisted of a stream of digitized pulses whose period was proportional to the sensed temperature, can be interfaced with a controller or a computer. The data acquisition system would then give a direct readout of the temperature through the use of a look-up table, a built-in algorithm, or a mathematical model. Because of the wide range of temperature measurement and because the sensor is made of carefully selected COTS parts, this work is directly applicable to the NASA Fundamental Aeronautics/Subsonic Fixed Wing Program--Jet Engine Distributed Engine Control Task and to the NASA Electronic Parts and Packaging (NEPP) Program. In the past, a temperature sensor was designed and built using an SOI operational amplifier, and a report was issued. This work used an SOI 555 timer as its core and is completely new work.

  1. Nanopillar array band-edge laser cavities on silicon-on-insulator for monolithic integrated light sources

    Science.gov (United States)

    Lee, Wook-Jae; Kim, Hyunseok; Farrell, Alan C.; Senanayake, Pradeep; Huffaker, Diana L.

    2016-02-01

    A simple and unique laser scheme comprised of a finite-size nanopillar array on a silicon-on-insulator grating layer is introduced for realizing an on-chip monolithically integrated light source. A photonic band-edge mode, confined by the grating substrate in the vertical direction, shows a quality factor as high as 4000. We show that the proposed laser cavity allows direct coupling into a waveguide, which is essential for monolithic integration. In addition, III-V semiconductor nanopillars are grown on a silicon-on-insulator grating substrate in order to demonstrate the feasibility of epitaxy on 3D surfaces. These results provide a practical solution for on-chip integration of a monolithic light source.

  2. Integrated circuits of silicon on insulator S.O.I. technologies: State of the art and perspectives

    International Nuclear Information System (INIS)

    Silicon On Insulator technologies have been proposed to increase the integrated circuits performances in radiation operation. Active researches are conducted, in France and abroad. This paper reviews briefly radiation effects phenomenology in that particular type of structure S.O.I. New results are presented that show very good radiation behaviour in term of speed, dose (10 to 100 megarad (Si)), dose rate and S.E.U. performances

  3. Design and fabrication of sub-μs silicon-on-insulator thermo-optic 4×4 switch matrix

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4×4 switch matrix with spot size converters (SSCs) and a new driving circuit are designed and fabricated. The introduction of a spot size converter (SSC) has decreased the insertion loss to less than 10dB and the new driving circuit has improved the response speed to less than 1μs.

  4. High Speed 2 × 2 Optical Switch in Silicon-on-Insulator Based on Plasma Dispersion Effect

    Institute of Scientific and Technical Information of China (English)

    SUN Fei; YU Jin-Zhong; CHEN Shao-Wu

    2005-01-01

    @@ Based on free carrier plasma dispersion effect, a 2 × 2 optical switch is fabricated in a silicon-on-insulator substrate by inductively coupled-plasma technology and ion implantation. The device has a Mach-Zehnder interferometer structure, in which two directional couplers serve as the power splitter and combiner. The switch presents an insertion loss of 3.04 dB and a response time of 496ns.

  5. Off-chip beam steering with a one-dimensional optical phased array on silicon-on-insulator

    OpenAIRE

    Van Acoleyen, Karel; Bogaerts, Wim; Jágerská, Jana; Le Thomas, Nicolas; Houdré, Romuald; Baets, Roel

    2009-01-01

    Optical phased arrays are versatile components enabling rapid and precise beam steering. An integrated approach is followed in which a 1D optical phased array is fabricated on silicon-on-insulator. The optical phased array consists of 16 parallel grating couplers spaced 2 mu m apart. Steering in one direction is done thermo-optically by means of a titanium electrode on top of the structure using the phased array principle, while steering in the other direction is accomplished by wavelength tu...

  6. Modelling of a DBR laser based on Raman effect in a silicon-on-insulator rib waveguide

    International Nuclear Information System (INIS)

    In this paper, third-order nonlinearities in silicon-on-insulator rib waveguides are investigated to obtain complete modelling, describing the behaviour of a stimulated Raman scattering based laser. The simulations of a distributed Bragg reflector laser operation in a time domain allow for the first time to study in detail the dependence of threshold and output powers on different device parameters. Both continuous wave and pulsed laser operations are theoretically demonstrated, as well as their dependence on device parameters

  7. Single rolled-up InGaAs/GaAs quantum dot microtubes integrated with silicon-on-insulator waveguides.

    Science.gov (United States)

    Tian, Zhaobing; Veerasubramanian, Venkat; Bianucci, Pablo; Mukherjee, Shouvik; Mi, Zetian; Kirk, Andrew G; Plant, David V

    2011-06-20

    We report on single rolled-up microtubes integrated with silicon-on-insulator waveguides. Microtubes with diameters of ~7 μm, wall thicknesses of ~250 nm, and lengths greater than 100 μm are fabricated by selectively releasing a coherently strained InGaAs/GaAs quantum dot layer from the handling GaAs substrate. The microtubes are then transferred from their host substrate to silicon-on-insulator waveguides by an optical fiber abrupt taper. The Q-factor of the waveguide coupled microtube is measured to be 1.5×10(5), the highest recorded for a semiconductor microtube cavity to date. The insertion loss and extinction ratio of the microtube are 1 dB and 34 dB respectively. By pumping the microtube with a 635 nm laser, the resonance wavelength is shifted by 0.7 nm. The integration of InGaAs/GaAs microtubes with silicon-on-insulator waveguides provides a simple, low loss, high extinction passive filter solution in the C+L band communication regime. PMID:21716453

  8. A new analytical model of high voltage silicon on insulator (SOI) thin film devices

    International Nuclear Information System (INIS)

    A new analytical model of high voltage silicon on insulator (SOI) thin film devices is proposed, and a formula of silicon critical electric field is derived as a function of silicon film thickness by solving a 2D Poisson equation from an effective ionization rate, with a threshold energy taken into account for electron multiplying. Unlike a conventional silicon critical electric field that is constant and independent of silicon film thickness, the proposed silicon critical electric field increases sharply with silicon film thickness decreasing especially in the case of thin films, and can come to 141 V/μm at a film thickness of 0.1 μm which is much larger than the normal value of about 30V/μm. From the proposed formula of silicon critical electric field, the expressions of dielectric layer electric field and vertical breakdown voltage (VB,V) are obtained. Based on the model, an ultra thin film can be used to enhance dielectric layer electric field and so increase vertical breakdown voltage for SOI devices because of its high silicon critical electric field, and with a dielectric layer thickness of 2μm the vertical breakdown voltages reach 852 and 300V for the silicon film thicknesses of 0.1 and 5μm, respectively. In addition, a relation between dielectric layer thickness and silicon film thickness is obtained, indicating a minimum vertical breakdown voltage that should be avoided when an SOI device is designed. 2D simulated results and some experimental results are in good agreement with analytical results. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  9. High-temperature silicon-on-insulator electronics for space nuclear power systems: Requirements and feasibility

    International Nuclear Information System (INIS)

    The authors have performed a study to determine whether silicon very-large-scale integrated circuits (VLSICs) can survive the high temperature (up to 3000C) and total-dose radiation environments (up to 10 Mrad over a 7-10 year system life) projected for a very-high-power space nuclear reactor platform. It is shown that circuits built on bulk epitaxial silicon cannot meet the temperature requirement because of excessive junction leakage currents. However, circuits built on silicon-on-insulator (SOI) material can meet both the radiation and temperature requirements. From a study of interface-trap generation and annealing, they find that one cannot depend on the elevated temperatures of a space nuclear power platform to automatically improve MOS total-dose radiation hardness. Still, at high-enough temperatures (above 1750C for these devices) and long enough times postirradiation, device response can be essentially independent of total dose. Reliability and performance issues are also discussed. They find that the temperature dependence of the threshold voltage of the SOI transistors is less than that of bulk transistors. Moreover, the ''zero-temperature coefficient'' current is much smaller for these ''floating-body'' SOI devices (-- 4 μA) than for bulk devices (-- 60 μA). Survivability of high-temperature SOI VLSICs in space, including immunity to transient and single-event upset (SEU), is also addressed. While a large number of practical issues remain to be resolved, no fundamental barrier against the successful development of VLSICs on SOI for use in very-high-power space nuclear reactor systems has been identified

  10. A high performance charge plasma PN-Schottky collector transistor on silicon-on-insulator

    International Nuclear Information System (INIS)

    In this paper, we propose a new high performance PN-Schottky collector (PN-SC) lateral bipolar junction transistor (BJT) on silicon-on-insulator (SOI). The proposed device addresses the problem of poor speed of conventional lateral PNP-BJT device by using a Schottky collector. Further, it does not use the conventional ways of ion implantation/diffusion to realize n and p type doped region. However, it uses metal electrodes of different work functions to create n and p type charge plasma in an undoped silicon film. The simulation study of the proposed lateral PN-SC bipolar charge plasma transistor on SOI (PN-SC-BCPT) device has shown a significant improvement in current gain (β), cutoff frequency (f T) and switching performance in comparison to conventional PNP-BJT and PNP-bipolar charge plasma transistor (PNP-BCPT) devices. A significantly high β is obtained in the proposed PN-SC-BCPT (∼2100) in comparison to PNP-BCPT (∼1450) and the conventional BJT (∼9) devices, respectively. It has been observed that there is 89.56% and 153.5% increase in f T for the proposed PN-SC-BCPT device (2.18 GHz) in comparison to conventional PNP-BJT (1.15 GHz) and PNP-BCPT (0.86 GHz) devices, respectively. Further, reductions of 24.6% and 15.4% in switching ON-delay and 66% and 30.76% in switching OFF-delay have been achieved in the proposed device based inverters in comparison to PNP-BCPT and the conventional BJT devices based inverters, respectively. Furthermore, the proposed device does not face doping related issues and the requirement of high temperature processing is absent. (paper)

  11. Design and characterization of silicon-on-insulator passive polarization converter with finite-element analysis

    Science.gov (United States)

    Deng, Henghua

    In this dissertation; the silicon-on-insulator (SOI) technology is introduced to the design and fabrication of passive polarization rotators (PR). Efficient and accurate full-vectorial finite-element eigenmode solvers as well as propagation schemes for characterizing novel SOI PRs are developed because commercial software packages based on finite-difference techniques are inefficient in dealing with arbitrary waveguide geometries. A novel configuration with asymmetric external waveguiding layers is proposed, which is advantageous for fabrication procedure, manufacturing tolerance, single-mode region, and conversion efficiency. By etching along the crystallographic plane, the angled-facet can be perfectly fabricated. Completely removing external waveguiding layer beside the sloped sidewall not only simplifies production procedures but also enhances fabrication tolerances. To accurately and efficiently characterize asymmetric slanted-angle SOI polarization converters, adaptive mesh generation procedures are incorporated into our finite-clement method (FEM) analysis. In addition, anisotropic perfectly-matched-layer (PML) boundary condition (BC) is employed in the beam propagation method (BPM) in order to effectively suppress reflections from the edges of the computation window. For the BPM algorithm, the power conservation is strictly monitored, the non-unitarity is thoroughly analyzed, and the inherent numerical dissipation is reduced by adopting the quasi-Crank-Nicholson scheme and adaptive complex reference index. Advantages of SOI polarization rotators over III-V counterparts are studied through comprehensive research on power exchange, single-mode condition, fabrication tolerance, wavelength stability, bending characteristics, loss and coupling properties. The performance of SOI PRs is stable for wavelengths in the ITU-T C-band and L-band, making such devices quite suitable for DWDM applications. Due to the flexible cross-section of SOI polarization converters

  12. Solar thermoelectric generators fabricated on a silicon-on-insulator substrate

    International Nuclear Information System (INIS)

    Solar thermal power generation is an attractive electricity generation technology as it is environment-friendly, has the potential for increased efficiency, and has high reliability. The design, modelling, and evaluation of solar thermoelectric generators (STEGs) fabricated on a silicon-on-insulator substrate are presented in this paper. Solar concentration is achieved by using a focusing lens to concentrate solar input onto the membrane of the STEG. A thermal model is developed based on energy balance and heat transfer equations using lumped thermal conductances. This thermal model is shown to be in good agreement with actual measurement results. For a 1 W laser input with a spot size of 1 mm, a maximum open-circuit voltage of 3.06 V is obtained, which translates to a temperature difference of 226 °C across the thermoelements and delivers 25 µW of output power under matched load conditions. Based on solar simulator measurements, a maximum TEG voltage of 803 mV was achieved by using a 50.8 mm diameter plano-convex lens to focus solar input to a TEG with a length of 1000 µm, width of 15 µm, membrane diameter of 3 mm, and 114 thermocouples. This translates to a temperature difference of 18 °C across the thermoelements and an output power under matched load conditions of 431 nW. This paper demonstrates that by utilizing a solar concentrator to focus solar radiation onto the hot junction of a TEG, the temperature difference across the device is increased; subsequently improving the TEG’s efficiency. By using materials that are compatible with standard CMOS and MEMS processes, integration of solar-driven TEGs with on-chip electronics is seen to be a viable way of solar energy harvesting where the resulting microscale system is envisioned to have promising applications in on-board power sources, sensor networks, and autonomous microsystems. (paper)

  13. Extreme High and Low Temperature Operation of the Silicon-On-Insulator Type CHT-OPA Operational Amplifier

    Science.gov (United States)

    Patterson, Richard; Hammoud, Ahmad; Elbuluk, Malik

    2008-01-01

    A new operational amplifier chip based on silicon-on-insulator technology was evaluated for potential use in extreme temperature environments. The CHT-OPA device is a low power, precision operational amplifier with rail-to-rail output swing capability, and it is rated for operation between -55 C and +225 C. A unity gain inverting circuit was constructed utilizing the CHT-OPA chip and a few passive components. The circuit was evaluated in the temperature range from -190 C to +200 C in terms of signal gain and phase shift, and supply current. The investigations were carried out to determine suitability of this device for use in space exploration missions and aeronautic applications under wide temperature incursion. Re-restart capability at extreme temperatures, i.e. power switched on while the device was soaked at extreme temperatures, was also investigated. In addition, the effects of thermal cycling under a wide temperature range on the operation of this high performance amplifier were determined. The results from this work indicate that this silicon-on-insulator amplifier chip maintained very good operation between +200 C and -190 C. The limited thermal cycling had no effect on the performance of the amplifier, and it was able to re-start at both -190 C and +200 C. In addition, no physical degradation or packaging damage was introduced due to either extreme temperature exposure or thermal cycling. The good performance demonstrated by this silicon-on-insulator operational amplifier renders it a potential candidate for use in space exploration missions or other environments under extreme temperatures. Additional and more comprehensive characterization is, however, required to establish the reliability and suitability of such devices for long term use in extreme temperature applications.

  14. A device model for thin silicon-on-insulator SiGe heterojunction bipolar transistors with saturation effects

    Institute of Scientific and Technical Information of China (English)

    Xu Xiao-Bo; Xu Kai-Xuan; Zhang He-Ming; Qin Shan-Shan

    2011-01-01

    In this paper,we describe the saturation effect of a silicon germanium (SiGe) heterojunction bipolar transistor (HBT) fabricated on a thin silicon-on-insulator (SOI) with a step-by-step derivation of the model formulation. The collector injection width,the internal base-collector bias,and the hole density at the base-collector junction interface are analysed by considering the unique features of the internal and the external parts of the collector,.they are different from those of a bulk counterpart.

  15. Substrate bias effects on collector resistance in SiGe heterojunction bipolar transistors on thin film silicon-on-insulator

    Institute of Scientific and Technical Information of China (English)

    Xu Xiao-Bo; Zhang He-Ming; Hu Hui-Yong; Qu Jiang-Tao

    2011-01-01

    An analytical expression for the collector resistance of a novel vertical SiGe heteroj unction bipolar transistor (HBT)on thin film silicon-on-insulator (SOI) is obtained with the substrate bias effects being considered. The resistance is found to decrease slowly and then quickly and to have kinks with the increase of the substrate-collector bias, which is quite different from that of a conventional bulk HBT. The model is consistent with the simulation result and the reported data and is useful to the frequency characteristic design of 0.13 μm millimeter-wave SiGe SOI BiCMOS devices.

  16. Efficient and compact TE-TM polarization converter built on silicon-on-insulator platform with a simple fabrication process

    DEFF Research Database (Denmark)

    Liu, Liu; Ding, Yunhong; Yvind, Kresten;

    2011-01-01

    An efficient TE-TM polarization converter built on a silicon-on-insulator nanophotonic platform is demonstrated. The strong cross-polarization coupling effect in air-cladded photonic-wire waveguides is employed to realize the conversion. A peak TE-TM coupling efficiency of 87% (-0.6 dB insertion...... loss) is measured experimentally. A polarization conversion efficiency of >92% with an overall insertion loss of <- 1.6 dB is obtained in a wavelength range of 40nm. The proposed device is compact, with a total length of 44 μm and can be fabricated with one lithography and etching step. © 2011 Optical...

  17. Efficient and compact TE-TM polarization converter built on silicon-on-insulator platform with a simple fabrication process.

    Science.gov (United States)

    Liu, Liu; Ding, Yunhong; Yvind, Kresten; Hvam, Jørn M

    2011-04-01

    An efficient TE-TM polarization converter built on a silicon-on-insulator nanophotonic platform is demonstrated. The strong cross-polarization coupling effect in air-cladded photonic-wire waveguides is employed to realize the conversion. A peak TE-TM coupling efficiency of 87% (-0.6 dB insertion loss) is measured experimentally. A polarization conversion efficiency of >92% with an overall insertion loss of <-1.6 dB is obtained in a wavelength range of 40 nm. The proposed device is compact, with a total length of 44 μm and can be fabricated with one lithography and etching step. PMID:21478982

  18. Design and analysis of polarization independent all-optical logic gates in silicon-on-insulator photonic crystal

    Science.gov (United States)

    Rani, Preeti; Kalra, Yogita; Sinha, R. K.

    2016-09-01

    In this paper, we have reported design and analysis of polarization independent all optical logic gates in silicon-on-insulator photonic crystal consisting of two dimensional honeycomb lattices with two different air holes exhibiting photonic band gap for both TE and TM mode in the optical communication window. The proposed structures perform as an AND optical logic gate and all the optical logic gates based on the phenomenon of interference. The response period and bit rate for TE and TM polarizations at a wavelength of 1.55 μm show improved results as reported earlier.

  19. Modeling and analysis of silicon-on-insulator elliptical microring resonators for future high-density integrated photonic circuits

    International Nuclear Information System (INIS)

    We propose a novel resonator containing an elliptical microring based on a silicon-on-insulator platform. Simulations using the three-dimensional finite-difference time-domain method show that the novel elliptical microring can efficiently enhance the mode coupling between straight bus waveguides and resonator waveguides or between adjacent resonators while preserving relatively high intrinsic quality factors with large free spectral range. The proposed resonator would be an alternative choice for future high-density integrated photonic circuits. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  20. Mach-Zehnder Interferometers with Asymmetric Modulation Arms in Applications of High Speed Silicon-on-Insulator Based Optical Switches

    Institute of Scientific and Technical Information of China (English)

    SUN Fei; YU Jin-Zhong

    2006-01-01

    @@ Modulation arms with different widths are introduced to Mach-Zehnder interferometers (MZIs) to obtain improved performance. Theoretical analysis and numerical simulation have shown that when the widths of the two arms are properly designed to achieve an inherent mπ/2 (m is an odd integer) optical phase difference between the arms, the asymmetric MZI presents higher modulation speed. Furthermore, the carrier-absorption induced divergence of insertion losses in silicon-on-insulator (SOI) based MZI optical switches can be obviously improved.

  1. Stimulated and spontaneous four-wave mixing in silicon-on-insulator coupled photonic wire nano-cavities

    OpenAIRE

    Azzini, Stefano; Grassani, Davide; Galli, Matteo; Gerace, Dario; Patrini, Maddalena; Liscidini, Marco; Velha, Philippe; Bajoni, Daniele

    2013-01-01

    We report on four-wave mixing in coupled photonic crystal nano-cavities on a silicon-on-insulator platform. Three photonic wire cavities are side-coupled to obtain three modes equally separated in energy. The structure is designed to be self-filtering, and we show that the pump is rejected by almost two orders of magnitudes. We study both the stimulated and the spontaneous four-wave mixing processes: owing to the small modal volume, we find that signal and idler photons are generated with a h...

  2. Stimulated and spontaneous four-wave mixing in silicon-on-insulator coupled photonic wire nano-cavities

    Science.gov (United States)

    Azzini, Stefano; Grassani, Davide; Galli, Matteo; Gerace, Dario; Patrini, Maddalena; Liscidini, Marco; Velha, Philippe; Bajoni, Daniele

    2013-07-01

    We report on four-wave mixing in coupled photonic crystal nano-cavities on a silicon-on-insulator platform. Three photonic wire cavities are side-coupled to obtain three modes equally separated in energy. The structure is designed to be self-filtering, and we show that the pump is rejected by almost two orders of magnitude. We study both the stimulated and the spontaneous four-wave mixing processes: owing to the small modal volume, we find that signal and idler photons are generated with a hundred-fold increase in efficiency as compared to silicon micro-ring resonators.

  3. Modulational instability in a silicon-on-insulator directional coupler: role of the coupling-induced group velocity dispersion.

    Science.gov (United States)

    Ding, W; Staines, O K; Hobbs, G D; Gorbach, A V; de Nobriga, C; Wadsworth, W J; Knight, J C; Skryabin, D V; Strain, M J; Sorel, M; De La Rue, R M

    2012-02-15

    We report frequency conversion experiments in silicon-on-insulator (SOI) directional couplers. We demonstrate that the evanescent coupling between two subwavelength SOI waveguides is strongly dispersive and significantly modifies modulational instability (MI) spectra through the coupling induced group velocity dispersion (GVD). As the separation between two 380-nm-wide silicon photonic wires decreases, the increasing dispersion of the coupling makes the GVD in the symmetric supermode more normal and suppresses the bandwidth of the MI gain observed for larger separations. PMID:22344142

  4. Photonic Crystal Microcavities in Advanced Silicon-On-Insulator Complementary-Metal-Oxide-Semiconductor Technology

    CERN Document Server

    Poulton, Christopher V; Orcutt, Jason S; Shainline, Jeffrey M; Wade, Mark T; Popovic, Milos A

    2014-01-01

    We demonstrate the first (to the best of our knowledge) monolithically integrated linear photonic crystal microcavities in an advanced SOI CMOS microelectronics process (IBM 45nm 12SOI) with no in-foundry process modifications. The cavities were integrated into a standard microelectronics design flow meeting process design rules, and included in a chip set alongside standard microelectronic circuits and microprocessors in the same device layer as transistors. We demonstrate both 1520nm wavelength telecom band and 1180nm cavity designs, using different structures owing to design rule limitations. Loaded Q's of 2,000 and 4,000, and extracted intrinsic loss Q's of the order of 100,000 and 50,000 are demonstrated. We also demonstrate an evanescent coupling geometry which entirely decouples the cavity and waveguide-coupling design, and investigate some of the mode features inherent in this coupling approach. The cavities support extended modes due to the thin device layer that limits optical confinement, and as a ...

  5. Novel high-voltage power lateral MOSFET with adaptive buried electrodes

    Institute of Scientific and Technical Information of China (English)

    Zhang Wen-Tong; Wu Li-Juan; Qiao Ming; Luo Xiao-Rong; Zhang Bo; Li Zhao-Ji

    2012-01-01

    A new high-voltage and low-specific on-resistance (Ron,sp) adaptive buried electrode (ABE) silicon-on-insulator (SOI) power lateral MOSFET and its analytical model of the electric fields are proposed.The MOSFET features are that the electrodes are in the buried oxide (BOX) layer,the negative drain voltage Vd is divided into many partial voltages and the output to the electrodes is in the buried oxide layer and the potentials on the electrodes change linearly from the drain to the source.Because the interface silicon layer potentials are lower than the neighboring electrode potentials,the electronic potential wells are formed above the electrode regions,and the hole poteutial wells are formed in the spacing of two neighbouring electrode regions.The interface hole concentration is much higher than the electron concentration through designing the buried layer electrode potentials.Based on the interface charge enhanced dielectric layer field theory,the electric field strength in the buried layer is enhanced.The vertical electric field EI and the breakdown voltage (BV) of ABE SOI are 545 V/μm and -587 V in the 50 μm long drift region and the 1 tm thick dielectric layer,and a low Ron,sp is obtained.Furthermore,the structure also alleviates the self-heating effect (SHE).The analytical model matches the simulation results.

  6. Fabrication of ultra-thin strained silicon on insulator by He implantation and ion cut techniques and characterization

    International Nuclear Information System (INIS)

    8-inch strained silicon on insulator (sSOI) wafer with 13 nm strained Si top layer has been obtained using He implantation, wafer bonding, layer transfer and selective etching techniques. Different from the conventional graded buffer layer with considerable thickness, the relaxed SiGe virtual substrate, which provides the lattice template for strained Si epitaxy, is achieved by the process combining He implantation and rapid thermal annealing. The strain relaxation in SiGe virtual substrate and the strain transfer from SiGe virtual substrate to the strained Si have been examined by X-ray diffraction reciprocal space mapping. The final 8-inch sSOI wafer is characterized for stress uniformity, thickness uniformity, crystalline quality, defect density and surface roughness using a variety of techniques and found to be in acceptable quality for the application in advanced device fabrication. - Highlights: • Thin SiGe virtual substrate is obtained with helium implantation method; • 8-inch strained silicon on insulator (sSOI) wafers have been fabricated; • Defect density, stress and thickness uniformity of 13 nm sSOI are characterized

  7. SiGeHBTs on Bonded SOI Incorporating Buried Silicide Layers

    OpenAIRE

    Bain, M.; El Mubarek, H A; Bonar, J. M.; Wang, Y.; Buiu, O.; Gamble, H.; Armstrong, B M; Hemment, P L; Hall, S.; Ashburn, P.

    2005-01-01

    A technology is described for fabricating SiGe hetero-junction bipolar transistors (HBTs) on wafer-bonded silicon-on-insulator (SOI) substrates that incorporate buried tungsten silicide layers for collector resistance reduction or buried groundplanes for crosstalk suppression. The physical structure of the devices is characterized using cross section transmission electron microscopy, and the electrical properties of the buried tungsten silicide layer are characterized using sheet resistance m...

  8. SiGe HBTs on bonded SOI incorporating buried silicide layers

    OpenAIRE

    Bain, M.; El Mubarek, A. W.; Bonar, J. M.; Wang, Y.; Buiu, O.; Gamble, H.; Armstrong, B M; Hemment, P. L. F.; Hall, Steven; Ashburn, Peter

    2005-01-01

    A technology is described for fabricating SiGe heterojunction bipolar transistors (HBTs) on wafer-bonded silicon-on-insulator (SOI) substrates that incorporate buried tungsten silicide layers for collector resistance reduction or buried groundplanes for crosstalk suppression. The physical structure of the devices is characterized using cross section transmission electron microscopy, and the electrical properties of the buried tungsten silicide layer are characterized using sheet resistance me...

  9. Thermo-optic Imbert-Fedorov effect in a prism-waveguide coupling system with silicon-on-insulator

    Science.gov (United States)

    Tang, Tingting; Li, Chaoyang; Luo, Li; Zhang, Yanfen; Yuan, Quan

    2016-07-01

    In this paper, a prism-waveguide coupling system based on silicon-on-insulator (SOI) is revisited. We find that thermo-optic Imbert-Fedorov (TOIF) effect displays in this four-layer optical system which has not been proposed before. Furthermore, we discuss the TOIF shifts in prism/SiO2/Si/SiO2 and prism/Au/Si/SiO2 waveguides with different parameters and study the observed phenomena from physical point of view. It is shown that the maximum IF shift can achieve 140 μm in a prism/Au/Si/SiO2 waveguide which is large enough to be directly measured by the calculation results. Accordingly, TOIF shift provides a temperature control method for the enhancement and modulation of IF shift.

  10. Focusing of light by negative refraction in a photonic crystal slab superlens on silicon-on-insulator substrate.

    Science.gov (United States)

    Matsumoto, Takashi; Eom, Kun-Sun; Baba, Toshihiko

    2006-09-15

    We experimentally demonstrate the light focusing by negative refraction in a photonic crystal slab superlens at wavelengths lambda of 1.26-1.42 microm. The photonic crystal slab was fabricated on silicon-on-insulator substrate with an interface structure optimized for low reflection and diffraction losses. The light focusing in the photonic crystal slab was clearly observed through the intentional out-of-plane radiation or scattering of guided light in the slab. The minimum focused spot width was limited to 1.8 microm(1.4 lambda) owing to aberrations. The focusing characteristics were in good agreement with those obtained from photonic band and finite-difference time-domain analyses. PMID:16936892

  11. An Analytical Avalanche Multiplication Model for Partially Depleted Silicon-on-Insulator SiGe Heterojunction Bipolar Transistors

    Institute of Scientific and Technical Information of China (English)

    XU Xiao-Bo; ZHANG He-Ming

    2011-01-01

    An analytical expression for avalanche multiplication of a novel vertical SiGe partially depleted heterojunction bipolar transistor (HBT) on a thin silicon-on-insulator (SOI) layer is obtained,considering vertical and horizontal impact ionization effects.The avalanche multiplication is found to be dependent on the collector width and doping concentration,and shows kinks with the increase of reverse base-collector bias,which is quite different from that of a conventional bulk HBT.The model is consistent with the experimental and simulation data and is found to be significant for the design and simulation of 0.13μm millimeter wave SiGe SOI BiCMOS technology.

  12. High-Q micro-ring resonators and grating couplers for silicon-on-insulator integrated photonic circuits

    International Nuclear Information System (INIS)

    An ultra-small integrated photonic circuit has been proposed, which incorporates a high-quality-factor passive micro-ring resonator (MR) linked to a vertical grating coupler on a standard silicon-on-insulator (SOI) substrate. The experimental results demonstrate that the MR propagation loss is 0.532 dB/cm with a 10 μm radius ring resonator, the intrinsic quality factor is as high as 202.000, the waveguide grating wavelength response curve is a 1 dB bandwidth of 40 nm at 1540 nm telecommunication wavelengths, and the measured fiber-to-fiber coupling loss is 10 dB. Furthermore, the resonator wavelength temperature dependence of the 450 nm wide micro-ring resonator is 54.1 pm/°C. Such vertical grating coupler and low loss MR-integrated components greatly promote a key element in biosensors and high-speed interconnect communication applications. (semiconductor integrated circuits)

  13. Investigation of the inhibiting outdiffusion of erbium atoms to a silicon-on-insulator surface after annealing at high temperature

    Institute of Scientific and Technical Information of China (English)

    Qin Xi-Feng; Li Hong-Zhen; Li Shuang; Ji Zi-Wu; Wang Hui-Ning; Wang Feng-Xiang; Fu Gang

    2012-01-01

    The annealing behaviour of 400 keV Er ions at a fluence of 2 × 1015 cm-2 implanted into silicon-on-insulator (SOI)samples is investigated by Rutherford backscattering spectrometry of 2.1 MeV He2+ ions with a multiple scattering model.It is found that the damage close to the SOI surface is almost removed after being annealed in O2 and N2 atmospheres,successively,at 900 ℃,and that only a small number of the Er atoms segregated to the surface of the SOI sample,whereas a large number of Er atoms diffused to a deeper position because of the affinity of Er for oxygen.For the SOI sample co-implanted with Er and O ions,there is no evident outdiffusion of Er atoms to the SOI surface after being annealed in N2 atmosphere at 900 ℃.

  14. Tunable complex-valued multi-tap microwave photonic filter based on single silicon-on-insulator microring resonator.

    Science.gov (United States)

    Lloret, Juan; Sancho, Juan; Pu, Minhao; Gasulla, Ivana; Yvind, Kresten; Sales, Salvador; Capmany, José

    2011-06-20

    A complex-valued multi-tap tunable microwave photonic filter based on single silicon-on-insulator microring resonator is presented. The degree of tunability of the approach involving two, three and four taps is theoretical and experimentally characterized, respectively. The constraints of exploiting the optical phase transfer function of a microring resonator aiming at implementing complex-valued multi-tap filtering schemes are also reported. The trade-off between the degree of tunability without changing the free spectral range and the number of taps is studied in-depth. Different window based scenarios are evaluated for improving the filter performance in terms of the side-lobe level. PMID:21716478

  15. Robust postfabrication trimming of ultracompact resonators on silicon on insulator with relaxed requirements on resolution and alignment.

    Science.gov (United States)

    Alipour, Payam; Atabaki, Amir H; Askari, Murtaza; Adibi, Ali; Eftekhar, Ali A

    2015-10-01

    One of the main drawbacks of the high-index-contrast silicon-on-insulator platform in integrated photonics is the high sensitivity of the resonance wavelength of resonators to dimensional variations caused by fabrication imperfection. In this work, we experimentally demonstrate an accurate postfabrication trimming technique for compensating the fabrication-induced variations in the resonance properties of nanophotonic devices. Using this technique, we reduce the variation of the resonance wavelength of 4 μm diameter microdonut resonators by more than 1 order of magnitude to about 25 pm, which is adequate for most interconnect, optical signal processing, and sensing applications. In addition, our proposed technique has improved misalignment toleration and throughput compared to previous reports. PMID:26421560

  16. Flexible Control of Light Propagation Using a Novel Photonic Crystal Hetero-Waveguide Based on Silicon-on-Insulator Slab

    International Nuclear Information System (INIS)

    We demonstrate a photonic crystal hetero-waveguide based on silicon-on-insulator (SOI) slab, consisting of two serially connected width-reduced photonic crystal waveguides with different radii of the air holes adjacent to the waveguide. We show theoretically that the transmission window of the structure corresponds to the transmission range common to both waveguides and it is in inverse proportion to the discrepancy between the two waveguides. Also the group velocity of guided mode can be changed from low to high or high to low, depending on which port of the structure the signal is input from just in the same device, and the variation is proportional to the discrepancy between the two waveguides. Using this novel structure, we realize flexible control of transmission window and group velocity of guided mode simultaneously. (fundamental areas of phenomenology(including applications))

  17. Fabrication of lithographically defined optical coupling facets for silicon-on-insulator waveguides by inductively coupled plasma etching

    International Nuclear Information System (INIS)

    We present a technique to lithographically define and fabricate all required optical facets on a silicon-on-insulator photonic integrated circuit by an inductively coupled plasma etch process. This technique offers 1 μm positioning accuracy of the facets at any location within the chip and eliminates the need of polishing. Facet fabrication consists of two separate steps to ensure sidewall verticality and minimize attack on the end surfaces of the waveguides. Protection of the waveguides by a thermally evaporated aluminum layer before the 40-70 μm deep optical facet etching has been proven essential in assuring the facet smoothness and integrity. Both scanning electron microscopy analysis and optical measurement results show that the quality of the facets prepared by this technique is comparable to the conventional facets prepared by polishing

  18. Experimental demonstration of ultracompact air hole photonic crystal ring resonator fabricated on silicon-on-insulator wafer.

    Science.gov (United States)

    Ren, Xiaoyuan; Feng, Lishuang; Lin, Zhili; Feng, Junbo

    2013-05-01

    A photonic crystal ring resonator (PCRR) of air hole arrays is fabricated on a silicon-on-insulator wafer by using electron-beam lithography and inductively coupled plasma etching. The designed PCRR is modeled and its performance is simulated by the two-dimensional finite difference time domain method. The simulation results show that the PCRR has two resonant wavelengths, 1598 and 1606 nm, and their corresponding quality factors are 3994 and 4015, respectively. A sample of the PCRR structure is fabricated and tested by the established experimental setup. Compared with the simulation results, the experimental resonant wavelengths drift to some extent and the quality factors are reduced by about one order of magnitude. The fabrication error and irregularity are the main reasons for the above results, which can be further reduced by improving the process technology. In addition, one more resonant wavelength emerged for the PCRR sample, which can be attributed to the change of the coupling strength. PMID:23632503

  19. Generation and confinement of mobile charges in buried oxide of SOI substrates

    International Nuclear Information System (INIS)

    We analyze the mechanisms of generation and confinement of mobile protons resulting from hydrogen annealing of SOI buried oxides. This study of the mechanisms of generation and confinement of mobile protons in the buried oxide of SOI wafers emphasizes the importance of H+ diffusion in the oxide in the formation of a mobile charge. Under specific electric field conditions the irradiation of these devices results in a pinning of this mobile charge at the bottom Si-SiO2 interface. Ab initio calculations are in progress to investigate the possible precursor defects in the oxide and detail the mechanism for mobile proton generation and confinement. (authors)

  20. Spectral-temporal description of dispersive wave emission and soliton trapping in micro-nano silicon-on-insulator waveguides

    Science.gov (United States)

    Wen, Jin; Ma, Chengju; Fan, Wei; Fu, Haiwei

    2015-08-01

    We numerically investigate the dispersive wave emission and soliton trapping in the process of femtosecond soliton propagation in silicon-on-insulator (SOI) waveguide. The cross-correlation frequency resolved optical gating (X-FROG) technique is employed to analyze the spectral-temporal dynamics of the soliton at different propagation distances. The numerical results show that dispersive wave emission can be blue-shifted (around 1300 nm) or red-shifted (around 1900 nm), which is determined by the dispersion slope for the pump wavelength (1550 nm). In addition, it can be found that red-shifted dispersive wave can supply contribution to the flatness of the supercontinuum generation. Through increasing the peak power of the soliton to 100 W, the soliton trapping can be observed by the edge of dispersive wave, which can be visualized in the form of multi-peak oscillation structure in the spectrogram when not considering the two-photon absorption (TPA). This work opens up the possibility for the realization of dispersive wave emission device in highly integrated circuit.

  1. Optically tunable full 360° microwave photonic phase shifter using three cascaded silicon-on-insulator microring resonators

    Science.gov (United States)

    Ehteshami, Nasrin; Zhang, Weifeng; Yao, Jianping

    2016-08-01

    A broadband optically tunable microwave phase shifter with a tunable phase shift covering the entire 360° range using three cascaded silicon-on-insulator (SOI) microring resonators (MRRs) that are optically pumped is proposed and experimentally demonstrated. The phase tuning is implemented based on the thermal nonlinear effect in the MRRs. By optically pumping the MRRs, the stored light in the MRRs is absorbed due to two photon absorption (TPA) to generate free carriers, which result in free carrier absorption (FCA). The FCA effect would lead to the heating of the MRRs and cause a redshift in the phase response, which is used to implement a microwave phase shifter with a tunable phase shift. The device is designated and fabricated on an SOI platform, which is experimentally evaluated. The experimental results show that by optically pumping the MRRs, a broadband microwave photonic phase shifter with a bandwidth of 7 GHz from 16 to 23 GHz with a tunable phase shift covering the entire 360° phase shift range is achieved.

  2. Total dose radiation and annealing responses of the back transistor of Silicon-On-Insulator pMOSFETs

    CERN Document Server

    Zhao, Xing; Li, Bin-Hong Li Gao Jian-Tou; Yu, Fang

    2014-01-01

    The total dose radiation and annealing responses of the back transistor of Silicon-On-Insulator (SOI) pMOSFETs have been studied by comparing with those of the back transistor of SOI nMOSFETs fabricated on the same wafer. The transistors were irradiated by 60Co {\\gamma}-rays with various doses, and the front transistors are biased in a Float-State and Off-State, respectively, during irradiation. The total dose radiation responses of the back transistors are characterized by their threshold voltage shifts. The results show that the total dose radiation response of the back transistor of SOI pMOSFETs, similar to that of SOI nMOSFETs, depends greatly on their bias conditions during irradiation. However, with the Float-State bias, rather than the Off-State bias, the back transistors of SOI pMOSFETs reveal a much higher sensitivity to total dose radiation, which is contrary to those of SOI nMOSFETs. In addition, it is also found that the total dose radiation effect of the back transistor of SOI pMOSFETs irradiated...

  3. Nano-beam electron diffraction evaluation of strain behaviour in nano-scale patterned strained silicon-on-insulator

    International Nuclear Information System (INIS)

    A major challenge for the application of strain engineering to enhance the performance of electronic devices is the quantification of strain on the nanoscale. Besides other techniques (Raman spectroscopy, X-ray diffraction) electron beam techniques allow strain analyses with a spatial resolution of a few nanometers and a reasonable strain sensitivity of 1 x 10-3 (relative to the lattice constant of silicon). In the present work, we address practical issues in the application of nano-beam electron diffraction (NBED) to probe the strain in strained silicon layers and sub-100 nm structures. The investigated specimens were prepared on biaxially tensile strained silicon-on-insulator substrates with an initial strain of ε = 0.6% or 0.8%. Results of the NBED experiments were compared to data obtained by other strain measurement techniques; amongst them the strain mapping by peak-pairs analysis of high-angle annular dark field (HAADF) images was especially considered (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Fabrication of open-top microchannel plate using deep X-ray exposure mask made with silicon on insulator substrate

    CERN Document Server

    Fujimura, T; Etoh, S I; Hattori, R; Kuroki, Y; Chang, S S

    2003-01-01

    We propose a high-aspect-ratio open-top microchannel plate structure. This type of microchannel plate has many advantages in electrophoresis. The plate was fabricated by deep X-ray lithography using synchrotron radiation (SR) light and the chemical wet etching process. A deep X-ray exposure mask was fabricated with a silicon on insulator (SOI) substrate. The patterned Si microstructure was micromachined into a thin Si membrane and a thick Au X-ray absorber was embedded in it by electroplating. A plastic material, polymethylmethacrylate (PMMA) was used for the plate substrate. For reduction of the exposure time and high-aspect-ratio fast wet development, the fabrication condition was optimized with respect to not the exposure dose but to the PMMA mean molecular weight (M.W.) changing after deep X-ray exposure as measured by gel permeation chromatography (GPC). Decrement of the PMMA M.W. and increment of the wet developer temperature accelerated the etching rate. Under optimized fabrication conditions, a microc...

  5. Infrared response of the lateral PIN structure of a highly titanium-doped silicon-on-insulator material

    Institute of Scientific and Technical Information of China (English)

    Ma Zhi-Hua; Cao Quan; Zuo Yu-Hua; Zheng Jun; Xue Chun-Lai; Cheng Bu-Wen; Wang Qi-Ming

    2011-01-01

    The intermediate band (IB) solar cell is a promising third-generation solar cell that could possibly achieve very high efficiency above the Shockley-Queisser limit.One of the promising ways to synthesize IB material is to introduce heavily doped deep level impurities in conventional semiconductors.High-doped Ti with a concentration of 1020 cm-3- 1021 cm-3 in the p-type top Si layer of silicon-on-insulator (SOI) substrate is obtained by ion implantation and rapid thermal annealing (RTA).Secondary ion mass spectrometry measurements confirm that the Ti concentration exceeds the theoretical Mott limit,the main requirement for the formation of an impurity intermediate band.Increased absorption is observed in the infrared (IR) region by Fourier transform infrared spectroscopy (FTIR) technology.By using a lateral p-i-n structure,an obvious infrared response in a range of 1100 nm-2000 nm is achieved in a heavily Ti-doped SOl substrate,suggesting that the improvement on IR photoresponse is a result of increased absorption in the IR.The experimental results indicate that heavily Ti-implanted Si can be used as a potential kind of intermediate-band photovoltaic material to utilize the infrared photons of the solar spectrum.

  6. 60-nm-thick basic photonic components and Bragg gratings on the silicon-on-insulator platform.

    Science.gov (United States)

    Zou, Zhi; Zhou, Linjie; Li, Xinwan; Chen, Jianping

    2015-08-10

    We demonstrate integrated basic photonic components and Bragg gratings using 60-nm-thick silicon-on-insulator strip waveguides. The ultra-thin waveguides exhibit a propagation loss of 0.61 dB/cm and a bending loss of approximately 0.015 dB/180° with a 30 μm bending radius (including two straight-bend waveguide junctions). Basic structures based on the ultra-thin waveguides, including micro-ring resonators, 1 × 2 MMI couplers, and Mach-Zehnder interferometers are realized. Upon thinning-down, the waveguide effective refractive index is reduced, making the fabrication of Bragg gratings possible using the standard 248-nm deep ultra-violet (DUV) photolithography process. The Bragg grating exhibits a stopband width of 1 nm and an extinction ratio of 35 dB, which is practically applicable as an optical filter or a delay line. The transmission spectrum can be thermally tuned via an integrated resistive micro-heater formed by a heavily doped silicon slab beside the waveguide. PMID:26367931

  7. Study on the dose rate upset effect of partially depleted silicon-on-insulator static random access memory

    International Nuclear Information System (INIS)

    This paper implements the study on the Dose Rate Upset effect of PDSOI SRAM (Partially Depleted Silicon-On-Insulator Static Random Access Memory) with the Qiangguang-I accelerator in Northwest Institute of Nuclear Technology. The SRAM (Static Random Access Memory) chips are developed by the Institute of Microelectronics of Chinese Academy of Sciences. It uses the full address test mode to determine the upset mechanisms. A specified address test is taken in the same time. The test results indicate that the upset threshold of the PDSOI SRAM is about 1×108 Gy(Si)/s. However, there are a few bits upset when the dose rate reaches up to 1.58 × 109 Gy(Si)/s. The SRAM circuit can still work after the high level γ ray pulse. Finally, the upset mechanism is determined to be the rail span collapse by comparing the critical charge with the collected charge after γ ray pulse. The physical locations of upset cells are plotted in the layout of the SRAM to investigate the layout defect. Then, some layout optimizations are made to improve the dose rate hardened performance of the PDSOI SRAM. (condensed matter: structure, thermal and mechanical properties)

  8. Synthesis of highly integrated optical network based on microdisk-resonator add-drop filters in silicon-on-insulator technology

    Science.gov (United States)

    Kaźmierczak, Andrzej; Dortu, Fabian; Giannone, Domenico; Bogaerts, Wim; Drouard, Emmanuel; Rojo-Romeo, Pedro; Gaffiot, Frederic

    2009-10-01

    We analyze a highly compact optical add-drop filter topology based on a pair of microdisk resonators and a bus waveguide intersection. The filter is further assessed on an integrated optical 4×4 network for optical on-chip communication. The proposed network structure, as compact as 50×50 μm, is fabricated in a CMOS-compatible process on a silicon-on-insulator (SOI) substrate. Finally, the experimental results demonstrate the proper operation of the fabricated devices.

  9. Dynamics of solid thin-film dewetting in the silicon-on-insulator system

    International Nuclear Information System (INIS)

    Using low-energy electron microscopy movies, we have measured the dewetting dynamics of single-crystal Si(001) thin films on SiO2 substrates. During annealing (T>700 deg. C), voids open in the Si, exposing the oxide. The voids grow, evolving Si fingers that subsequently break apart into self-organized three-dimensional (3D) Si nanocrystals. A kinetic Monte Carlo model incorporating surface and interfacial free energies reproduces all the salient features of the morphological evolution. The dewetting dynamics is described using an analytic surface-diffusion-based model. We demonstrate quantitatively that Si dewetting from SiO2 is mediated by surface-diffusion driven by surface free-energy minimization.

  10. Advanced TEM Characterization for the Development of 28-14nm nodes based on fully-depleted Silicon-on-Insulator Technology

    International Nuclear Information System (INIS)

    The growing demand for wireless multimedia applications (smartphones, tablets, digital cameras) requires the development of devices combining both high speed performances and low power consumption. A recent technological breakthrough making a good compromise between these two antagonist conditions has been proposed: the 28-14nm CMOS transistor generations based on a fully-depleted Silicon-on-Insulator (FD-SOI) performed on a thin Si film of 5-6nm. In this paper, we propose to review the TEM characterization challenges that are essential for the development of extremely power-efficient System on Chip (SoC)

  11. Material and device engineering in fully depleted silicon-on-insulator transistors to realize a steep subthreshold swing using negative capacitance

    Science.gov (United States)

    Ota, Hiroyuki; Migita, Shinji; Hattori, Junichi; Fukuda, Koichi; Toriumi, Akira

    2016-08-01

    This paper discusses material and device engineering in field-effect transistors (FETs) with HfO2-based ferroelectric gate insulators to attain a precipitous subthreshold swing (SS) by exploiting negative capacitance. Our physical analysis based on a new concept of a negative dielectric constant reveals that fully depleted silicon-on-insulator (FD-SOI) channels with a modest remnant polarization P r (3 µC/cm2 at most) are more suitable for realizing SS HfO2-based ferroelectric materials. We also confirm SS HfO2 gate insulators by device simulation.

  12. Novel Folding Large-Scale Optical Switch Matrix with Total Internal Reflection Mirrors on Silicon-on-Insulator by Anisotropy Chemical Etching

    Institute of Scientific and Technical Information of China (English)

    LIU Jing-Wei; YU Jin-Zhong; CHEN Shao-Wu

    2005-01-01

    A compact optical switch matrix was designed, in which light circuits were folded by total internal reflective (TIR) mirrors. Two key elements, 2 × 2 switch and TIR mirror, have been fabricated on silicon-on-insulator wafer by anisotropy chemical etching. The 2 × 2 switch showed very low power consumption of 140mW and avery high speed of 8 ± 1 μs. An improved design for the TIR mirror was developed, and the fabricated mirror with smooth and vertical reflective facet showed low excess loss of 0.7 ± 0.3 dB at 1.55μm.

  13. A comparison of the etching behaviour of the FS Cr-free SOI with that of the Secco etching solution on silicon-on-insulator substrates

    International Nuclear Information System (INIS)

    The 'FS Cr-free SOI' etching solution has been presented as a new defect etching solution especially developed for application on silicon-on-insulator (SOI) substrates fabricated by the Smart-CutTM technology. It is free of toxic hexavalent chromium. Very efficient in revealing crystal defects it is a promising candidate for Secco replacement on SOI. The aim of this paper is to present and compare the most important characteristics of both defect etching solutions. The defect delineation mechanism common to both Secco and FS Cr-free SOI and etching mechanisms will also be discussed.

  14. A low on-resistance buried current path SOI p-channel LDMOS compatible with n-channel LDMOS

    Institute of Scientific and Technical Information of China (English)

    Zhou Kun; Luo Xiao-Rong; Fan Yuan-Hang; Luo Yin-Chun; Hu Xia-Rong; Zhang Bo

    2013-01-01

    A novel low specific on-resistance (Ron,sp) silicon-on-insulator (SOI) p-channel lateral double-diffused metal-oxide semiconductor (pLDMOS) compatible with high voltage (HV) n-channel LDMOS (nLDMOS) is proposed.The pLDMOS is built in the N-type SOI layer with a buried P-type layer acting as a current conduction path in the on-state (BP SOI pLDMOS).Its superior compatibility with the HV nLDMOS and low voltage (LV) complementary metal-oxide semiconductor (CMOS) circuitry which are formed on the N-SOI layer can be obtained.In the off-state the P-buried layer built in the N-SOI layer causes multiple depletion and electric field reshaping,leading to an enhanced (reduced) surface field (RESURF)effect.The proposed BP SOI pLDMOS achieves not only an improved breakdown voltage (BV) but also a significantly reduced Ron,sp.The BV of the BP SOI pLDMOS increases to 319 V from 215 V of the conventional SOI pLDMOS at the same half cell pitch of 25 μm,and Ron,sp decreases from 157 mΩ·cm2 to 55 mΩ·cm2.Compared with the PW SOI pLDMOS,the BP SOI pLDMOS also reduces the Ron,sp by 34% with almost the same BV.

  15. Analytical base-collector depletion capacitance in vertical SiGe heterojunction bipolar transistors fabricated on CMOS-compatible silicon on insulator

    Institute of Scientific and Technical Information of China (English)

    Xu Xiao-Bo; Zhang He-Ming; Hu Hui-Yong; Ma Jian-Li; Xu Li-Jun

    2011-01-01

    The base-collector depletion capacitance for vertical SiGe npn heterojunction bipolar transistors (HBTs) on silicon on insulator (SOI) is split into vertical and lateral parts. This paper proposes a novel analytical depletion capacitance model of this structure for the first time. A large discrepancy is predicted when the present model is compared with the conventional depletion model, and it is shown that the capacitance decreases with the increase of the reverse collectorbase bias-and shows a kink as the reverse collector-base bias reaches the effective vertical punch-through voltage while the voltage differs with the collector doping concentrations, which is consistent with measurement results. The model can be employed for a fast evaluation of the depletion capacitance of an SOI SiGe HBT and has useful applications on the design and simulation of high performance SiGe circuits and devices.

  16. Analysis and design of tunable wideband microwave photonics phase shifter based on Fabry-Perot cavity and Bragg mirrors in silicon-on-insulator waveguide.

    Science.gov (United States)

    Qu, Pengfei; Zhou, Jingran; Chen, Weiyou; Li, Fumin; Li, Haibin; Liu, Caixia; Ruan, Shengping; Dong, Wei

    2010-04-20

    We designed a microwave (MW) photonics phase shifter, consisting of a Fabry-Perot filter, a phase modulation region (PMR), and distributed Bragg reflectors, in a silicon-on-insulator rib waveguide. The thermo-optics effect was employed to tune the PMR. It was theoretically demonstrated that the linear MW phase shift of 0-2pi could be achieved by a refractive index variation of 0-9.68x10(-3) in an ultrawideband (about 38?GHz-1.9?THz), and the corresponding tuning resolution was about 6.92 degrees / degrees C. The device had a very compact size. It could be easily integrated in silicon optoelectronic chips and expected to be widely used in the high-frequency MW photonics field. PMID:20411021

  17. Material and device engineering in fully depleted silicon-on-insulator transistors to realize a steep subthreshold swing using negative capacitance

    Science.gov (United States)

    Ota, Hiroyuki; Migita, Shinji; Hattori, Junichi; Fukuda, Koichi; Toriumi, Akira

    2016-08-01

    This paper discusses material and device engineering in field-effect transistors (FETs) with HfO2-based ferroelectric gate insulators to attain a precipitous subthreshold swing (SS) by exploiting negative capacitance. Our physical analysis based on a new concept of a negative dielectric constant reveals that fully depleted silicon-on-insulator (FD-SOI) channels with a modest remnant polarization P r (3 µC/cm2 at most) are more suitable for realizing SS < 60 mV/decade than a higher P r of 10 µC/cm2, which is commonly reported for HfO2-based ferroelectric materials. We also confirm SS < 60 mV/decade in more than 5 orders of the subthreshold current in FD-SOI FETs with ferroelectric HfO2 gate insulators by device simulation.

  18. A high performance charge plasma based lateral bipolar transistor on selective buried oxide

    International Nuclear Information System (INIS)

    In this paper, we present a new structure of lateral bipolar transistor on selective buried oxide. The device does not use highly doped regions; however, it employs the concept of creating n and p type charge plasma in undoped silicon by using metal electrodes of different work functions. The proposed device is named as the selective buried oxide based bipolar charge plasma transistor (SELBOX-BCPT). An extensive 2D simulation study has revealed that the proposed SELBOX-BCPT device not only possesses all the advantages of the conventional BCPT device, but it also addresses various severe problems of the BCPT device. A significant improvement in major issues of poor cutoff frequency (fT), low breakdown voltage and thermal efficiency has been achieved. It has been observed that the fT has increased by ∼94.6%, the breakdown voltage by 23.47% and the device is much cooler than the conventional BCPT device. A large current gain is obtained in the proposed device and is on a par with the conventional BCPT device. Further, by using mixed-mode simulation feature of the Atlas simulator, inverting amplifiers based on SELBOX-BCPT and the conventional BCPT have been realized. A significant improvement of 15% in switching-on transient time and 25.8% in switching-off transient time has been achieved in the proposed device in comparison to the conventional BCPT device. (paper)

  19. Fabrication of core-shell nanostructures via silicon on insulator dewetting and germanium condensation: towards a strain tuning method for SiGe-based heterostructures in a three-dimensional geometry.

    Science.gov (United States)

    Naffouti, Meher; David, Thomas; Benkouider, Abdelmalek; Favre, Luc; Cabie, Martiane; Ronda, Antoine; Berbezier, Isabelle; Abbarchi, Marco

    2016-07-29

    We report on a novel method for the implementation of core-shell SiGe-based nanocrystals combining silicon on insulator dewetting in a molecular beam epitaxy reactor with an ex situ Ge condensation process. With an in situ two-step process (annealing and Ge deposition) we produce two families of islands on the same sample: Si-rich, formed during the first step and, all around them, Ge-rich formed after Ge deposition. By increasing the amount of Ge deposited on the annealed samples from 0 to 18 monolayers, the islands' shape in the Si-rich zones can be tuned from elongated and flat to more symmetric and with a larger vertical aspect ratio. At the same time, the spatial extension of the Ge-rich zones is progressively increased as well as the Ge content in the islands. Further processing by ex situ rapid thermal oxidation results in the formation of a core-shell composition profile in both Si and Ge-rich zones with atomically sharp heterointerfaces. The Ge condensation induces a Ge enrichment of the islands' shell of up to 50% while keeping a pure Si core in the Si-rich zones and a ∼25% SiGe alloy in the Ge-rich ones. The large lattice mismatch between core and shell, the absence of dislocations and the islands' monocrystalline nature render this novel class of nanostructures a promising device platform for strain-based band-gap engineering. Finally, this method can be used for the implementation of ultralarge scale meta-surfaces with dielectric Mie resonators for light manipulation at the nanoscale. PMID:27302611

  20. Fabrication of core–shell nanostructures via silicon on insulator dewetting and germanium condensation: towards a strain tuning method for SiGe-based heterostructures in a three-dimensional geometry

    Science.gov (United States)

    Naffouti, Meher; David, Thomas; Benkouider, Abdelmalek; Favre, Luc; Cabie, Martiane; Ronda, Antoine; Berbezier, Isabelle; Abbarchi, Marco

    2016-07-01

    We report on a novel method for the implementation of core–shell SiGe-based nanocrystals combining silicon on insulator dewetting in a molecular beam epitaxy reactor with an ex situ Ge condensation process. With an in situ two-step process (annealing and Ge deposition) we produce two families of islands on the same sample: Si-rich, formed during the first step and, all around them, Ge-rich formed after Ge deposition. By increasing the amount of Ge deposited on the annealed samples from 0 to 18 monolayers, the islands’ shape in the Si-rich zones can be tuned from elongated and flat to more symmetric and with a larger vertical aspect ratio. At the same time, the spatial extension of the Ge-rich zones is progressively increased as well as the Ge content in the islands. Further processing by ex situ rapid thermal oxidation results in the formation of a core–shell composition profile in both Si and Ge-rich zones with atomically sharp heterointerfaces. The Ge condensation induces a Ge enrichment of the islands’ shell of up to 50% while keeping a pure Si core in the Si-rich zones and a ∼25% SiGe alloy in the Ge-rich ones. The large lattice mismatch between core and shell, the absence of dislocations and the islands’ monocrystalline nature render this novel class of nanostructures a promising device platform for strain-based band-gap engineering. Finally, this method can be used for the implementation of ultralarge scale meta-surfaces with dielectric Mie resonators for light manipulation at the nanoscale.

  1. Ultra-thin body & buried oxide SOI substrate development and qualification for Fully Depleted SOI device with back bias capability

    Science.gov (United States)

    Schwarzenbach, Walter; Nguyen, Bich-Yen; Allibert, Frederic; Girard, Christophe; Maleville, Christophe

    2016-03-01

    This paper reviews the properties of the SOI wafers fabricated using the Smart Cut™ technology, with ultra-thin body and buried oxide (BOX) required for the FD-SOI CMOS platform. It focuses on the parameters that require specific attention for this technology, namely, the top silicon layer thickness uniformity and buried oxide reliability. The first one is linked to the threshold voltage variability and the second to the active role played by the BOX when a back-bias is used. An overview of the specific process optimization and metrology developed to achieve the targeted specifications is given.

  2. Influence of buried interfaces on the charge dynamics in oxide thin films

    Science.gov (United States)

    Pant, Shreedhar Nath

    Influence of buried interfaces was investigated in the ZnO thin films grown on Si at 120°C, 150°C, 170°C, and 200°C. by employing PL and SPV. The PL spectrum of samples grown at higher temperatures showed bandgap emission at ˜3.3 eV, shallow defects emission ˜3.0 eV and visible emission at ˜2.4 eV. On the other hand, the visible emission for the sample grown at 120°C visible emission is red-shifted to ˜2.1eV. SPV spectra of films grown at higher temperatures in nitrogen gas showed bandgap transition whereas 120°C grown sample only showed weak band transition. Instead one can see transition primarily in IR region due to silicon or silicon oxide. Furthermore, analysis of the transient SPV curves in both nitrogen and vacuum revealed two different characteristic time scales (fast and slow) possibly reflecting contributions of both the ZnO surface and the ZnO/Si buried interface.

  3. Characterization of dielectric materials in thin layers for the development of S.O.I. (Silicon on Insulator) substrates

    International Nuclear Information System (INIS)

    This thesis deals with the characterization of oxide layer placed inside S.O.I. substrates and submitted to irradiation. This type of material is used for the development of hardened electronic components, that is to say components able to be used in a radiative environment. The irradiation induces charges (electrons or holes) in the recovered oxide. A part of these charges is trapped which leads to changes of the characteristics of the electronic components made on these substrates. The main topic of this study is the characterization of trapping properties of recovered oxides and more particularly of 'Unibond' material carried out with a new fabrication process: the 'smart-cut' process. This work is divided into three parts: - study with one carrier: this case is limited to low radiation doses where is only observed holes trapping. The evolution of the physical and chemical properties of the 'Unibond' material recovered oxide has been revealed, this evolution being due to the fabrication process. - Study with two carriers: in this case, there is trapping of holes and electrons. This type of trapping is observed in the case of strong radiation doses. A new type of electrons traps has been identified with the 'Unibond' material oxide. The transport and the trapping of holes and electrons have been studied in the case of transient phenomena created by short radiative pulses. This study has been carried out using a new measurement method. - Study with three carriers: here are added to holes and electrons the protons introduced in the recovered oxide by the annealing under hydrogen. These protons are movable when they are submitted to the effect of an electric field and they induce a memory effect according to their position in the oxide. These different works show that the 'Unibond' material is a very good solution for the future development of S.O.I. (author)

  4. Monolithically Integrated InGaAs Nanowires on 3D Structured Silicon-on-Insulator as a New Platform for Full Optical Links.

    Science.gov (United States)

    Kim, Hyunseok; Farrell, Alan C; Senanayake, Pradeep; Lee, Wook-Jae; Huffaker, Diana L

    2016-03-01

    Monolithically integrated III-V semiconductors on a silicon-on-insulator (SOI) platform can be used as a building block for energy-efficient on-chip optical links. Epitaxial growth of III-V semiconductors on silicon, however, has been challenged by the large mismatches in lattice constants and thermal expansion coefficients between epitaxial layers and silicon substrates. Here, we demonstrate for the first time the monolithic integration of InGaAs nanowires on the SOI platform and its feasibility for photonics and optoelectronic applications. InGaAs nanowires are grown not only on a planar SOI layer but also on a 3D structured SOI layer by catalyst-free metal-organic chemical vapor deposition. The precise positioning of nanowires on 3D structures, including waveguides and gratings, reveals the versatility and practicality of the proposed platform. Photoluminescence measurements exhibit that the composition of ternary InGaAs nanowires grown on the SOI layer has wide tunability covering all telecommunication wavelengths from 1.2 to 1.8 μm. We also show that the emission from an optically pumped single nanowire is effectively coupled and transmitted through an SOI waveguide, explicitly showing that this work lays the foundation for a new platform toward energy-efficient optical links. PMID:26901448

  5. Development for Germanium Blocked Impurity Band Far-Infrared Image Sensors with Fully-Depleted Silicon-On-Insulator CMOS Readout Integrated Circuit

    Science.gov (United States)

    Wada, T.; Arai, Y.; Baba, S.; Hanaoka, M.; Hattori, Y.; Ikeda, H.; Kaneda, H.; Kochi, C.; Miyachi, A.; Nagase, K.; Nakaya, H.; Ohno, M.; Oyabu, S.; Suzuki, T.; Ukai, S.; Watanabe, K.; Yamamoto, K.

    2016-07-01

    We are developing far-infrared (FIR) imaging sensors for low-background and high-sensitivity applications such as infrared astronomy. Previous FIR monolithic imaging sensors, such as an extrinsic germanium photo-conductor (Ge PC) with a PMOS readout integrated circuit (ROIC) hybridized by indium pixel-to-pixel interconnection, had three difficulties: (1) short cut-off wavelength (120 \\upmu m), (2) large power consumption (10 \\upmu W/pixel), and (3) large mismatch in thermal expansion between the Ge PC and the Si ROIC. In order to overcome these difficulties, we developed (1) a blocked impurity band detector fabricated by a surface- activated bond technology, whose cut-off wavelength is longer than 160 \\upmu m, (2) a fully-depleted silicon-on-insulator CMOS ROIC which works below 4 K with 1 \\upmu W/pixel operating power, and (3) a new concept, Si-supported Ge detector, which shows tolerance to thermal cycling down to 3 K. With these new techniques, we are now developing a 32 × 32 FIR imaging sensor.

  6. Galvanically coupled gold/silicon-on-insulator microstructures in hydrofluoric acid electrolytes: finite element simulation and morphological analysis of electrochemical corrosion

    International Nuclear Information System (INIS)

    During the post-processing of silicon (Si) microsystems in hydrofluoric acid (HF)-based solutions, a galvanic couple is formed between the Si (anode) and metallic overlayers (cathode), such as gold (Au). Electrochemical etching (corrosion) of the exposed Si results in a porous silicon (PS) film and substantial degradation of mechanical and electrical properties occur. Focused ion beam milling (FIB) of micro-scale silicon-on-insulator (SOI) devices post-processed using HF solutions is used to determine the depth uniformity of the PS as a function of the geometry of the device. As the dopant concentration of the Si is critical to corrosion, dynamic SIMS is employed to assess the dopant concentration profile in SOI. As a means to model corrosion, we present a finite element method (FEM) enabled simulation to model the galvanic corrosion process on Si microsystems exposed to HF. The model uses an analogy to heat transfer to represent electrical conduction and accounts for electrochemical kinetics using the Tafel equation to represent empirical electrochemical measurements of Au and Si in HF. The model reproduces the current-limited condition resulting from the finite surface area of metal relative to silicon and predicts the uniform etch rate across the device for surfactant-enhanced HF solutions as seen in FIB. This work can be extended to applications where forming PS using a galvanic method may be advantageous.

  7. High-responsivity vertical-illumination Si/Ge uni-traveling-carrier photodiodes based on silicon-on-insulator substrate

    Science.gov (United States)

    Li, Chong; Xue, Chunlai; Liu, Zhi; Cong, Hui; Cheng, Buwen; Hu, Zonghai; Guo, Xia; Liu, Wuming

    2016-06-01

    Si/Ge uni-traveling carrier photodiodes exhibit higher output current when space-charge effect is overcome and the thermal effects is suppressed. High current is beneficial for increasing the dynamic range of various microwave photonic systems and simplifying high-bit-rate digital receivers in many applications. From the point of view of packaging, detectors with vertical-illumination configuration can be easily handled by pick-and-place tools and are a popular choice for making photo-receiver modules. However, vertical-illumination Si/Ge uni-traveling carrier (UTC) devices suffer from inter-constraint between high speed and high responsivity. Here, we report a high responsivity vertical-illumination Si/Ge UTC photodiode based on a silicon-on-insulator substrate. When the transmission of the monolayer anti-reflection coating was maximum, the maximum absorption efficiency of the devices was 1.45 times greater than the silicon substrate owing to constructive interference. The Si/Ge UTC photodiode had a dominant responsivity at 1550 nm of 0.18 A/W, a 50% improvement even with a 25% thinner Ge absorption layer.

  8. 110 GHz hybrid mode-locked fiber laser with enhanced extinction ratio based on nonlinear silicon-on-insulator micro-ring-resonator (SOI MRR)

    Science.gov (United States)

    Liu, Yang; Hsu, Yung; Chow, Chi-Wai; Yang, Ling-Gang; Yeh, Chien-Hung; Lai, Yin-Chieh; Tsang, Hon-Ki

    2016-03-01

    We propose and experimentally demonstrate a new 110 GHz high-repetition-rate hybrid mode-locked fiber laser using a silicon-on-insulator microring-resonator (SOI MRR) acting as the optical nonlinear element and optical comb filter simultaneously. By incorporating a phase modulator (PM) that is electrically driven at a fraction of the harmonic frequency, an enhanced extinction ratio (ER) of the optical pulses can be produced. The ER of the optical pulse train increases from 3 dB to 10 dB. As the PM is only electrically driven by the signal at a fraction of the harmonic frequency, in this case 22 GHz (110 GHz/5 GHz), a low bandwidth PM and driving circuit can be used. The mode-locked pulse width and the 3 dB spectral bandwidth of the proposed mode-locked fiber laser are measured, showing that the optical pulses are nearly transform limited. Moreover, stability evaluation for an hour is performed, showing that the proposed laser can achieve stable mode-locking without the need for optical feedback or any other stabilization mechanism.

  9. The impact of etched trenches geometry and dielectric material on the electrical behaviour of silicon-on-insulator self-switching diodes

    Energy Technology Data Exchange (ETDEWEB)

    Farhi, G; Charlebois, S A [Departement de genie electrique et genie informatique, et Institut interdisciplinaire d' innovation technologique (3IT), Universite de Sherbrooke, 2500, Boulevard de l' Universite, J1K 2R1, Sherbrooke, QC (Canada); Morris, D [Departement de physique et Institut interdisciplinaire d' innovation technologique (3IT), Universite de Sherbrooke, 2500, Boulevard de l' Universite, J1K 2R1, Sherbrooke, QC (Canada); Raskin, J-P, E-mail: ghania.farhi@usherbrooke.ca [Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Universite catholique de Louvain, Place du Levant, 3, B-1348 Louvain-la-Neuve (Belgium)

    2011-10-28

    Hole electrical transport in a p-doped nanochannel defined between two L-shape etched trenches made on a silicon-on-insulator substrate is investigated using a TCAD-Medici simulator. We study the impact of the etched trenches' geometry and dielectric filling materials on the current-voltage characteristics of the device. Carrier accumulation on frontiers defined by the trenches causes a modulation of the hole density inside the conduction channel as the bias voltage varies and this gives rise to a diode-like characteristic. For a 1.2 {mu}m-long channel, plots of the electric field distribution show that a nonlinear transport regime is reached at a moderate reverse and forward bias of {+-} 2 V. Plots of the carrier velocity along the conduction channel show that holes remain hot for a few hundreds of nm outside the nanometre-wide channel, at a bias of {+-} 10 V. Filling the etched trenches with a high-{kappa} dielectric material gives rise to a lower threshold voltage, V{sub th}. A similar decrease of V{sub th} is also achieved by reducing the longitudinal and/or the transverse trench width. Our simulation results provide useful design guidelines for future integrated self-switching-diode-based circuits.

  10. The impact of etched trenches geometry and dielectric material on the electrical behaviour of silicon-on-insulator self-switching diodes

    International Nuclear Information System (INIS)

    Hole electrical transport in a p-doped nanochannel defined between two L-shape etched trenches made on a silicon-on-insulator substrate is investigated using a TCAD-Medici simulator. We study the impact of the etched trenches' geometry and dielectric filling materials on the current-voltage characteristics of the device. Carrier accumulation on frontiers defined by the trenches causes a modulation of the hole density inside the conduction channel as the bias voltage varies and this gives rise to a diode-like characteristic. For a 1.2 μm-long channel, plots of the electric field distribution show that a nonlinear transport regime is reached at a moderate reverse and forward bias of ± 2 V. Plots of the carrier velocity along the conduction channel show that holes remain hot for a few hundreds of nm outside the nanometre-wide channel, at a bias of ± 10 V. Filling the etched trenches with a high-κ dielectric material gives rise to a lower threshold voltage, Vth. A similar decrease of Vth is also achieved by reducing the longitudinal and/or the transverse trench width. Our simulation results provide useful design guidelines for future integrated self-switching-diode-based circuits.

  11. High-responsivity vertical-illumination Si/Ge uni-traveling-carrier photodiodes based on silicon-on-insulator substrate

    CERN Document Server

    Li, Chong; Liu, Zhi; Cong, Hui; Cheng, Buwen; Guo, Xia; Liu, Wuming

    2015-01-01

    Si/Ge uni-traveling carrier photodiodes exhibit higher output current when space-charge effects are overcome and thermal effects are suppressed, which is highly beneficial for increasing the dynamic range of various microwave photonic systems and simplifying high-bit-rate digital receivers in different applications. From the point of view of packaging, detectors with vertical-illumination configuration can be easily handled by pick-and-place tools and are a popular choice for making photo-receiver modules. However, vertical-illumination Si/Ge uni-traveling carrier (UTC) devices suffer from inter-constraint between high speed and high responsivity. Here, we report a high responsivity vertical-illumination Si/Ge UTC photodiode based on a silicon-on-insulator substrate. The maximum absorption efficiency of the devices was 2.4 times greater than the silicon substrate owing to constructive interference. The Si/Ge UTC photodiode was successfully fabricated and had a dominant responsivity at 1550 nm of 0.18 A/W, a 5...

  12. Optical properties of ion-implanted silicon and separation by implantation of oxygen silicon-on-insulator substrates in the infrared: Study of B+ and P2+ implantation doping

    International Nuclear Information System (INIS)

    The optical properties of ion implanted silicon and silicon-on-insulator substrates have been studied by Fourier transform infrared spectroscopy. The influence of the implanted-ion mass in changing the refractive index of a silicon target has been examined by implanting 80 keV 11B+ and 62P2+ ions respectively. A refractive index rise not exceeding 2% and total amorphization were observed respectively in the vicinity of the Si surface after boron and phosphorous implantations. Free carrier profiles generated after thermal annealing at 950 oC/30 min and 1150 oC/120 min were modeled by Pearson and half-Gaussian distributions respectively. The phosphorous implantation was also performed in silicon-on-insulator substrates, yielding after annealing nearly homogeneous free-carrier profiles in the top-Si layer and optical mobility values comparable to those of bulk-Si.

  13. Utilizing a shallow trench isolation parasitic transistor to characterize the total ionizing dose effect of partially-depleted silicon-on-insulator input/output n-MOSFETs

    International Nuclear Information System (INIS)

    We investigate the effects of 60Co γ-ray irradiation on the 130 nm partially-depleted silicon-on-isolator (PDSOI) input/output (I/O) n-MOSFETs. A shallow trench isolation (STI) parasitic transistor is responsible for the observed hump in the back-gate transfer characteristic curve. The STI parasitic transistor, in which the trench oxide acts as the gate oxide, is sensitive to the radiation, and it introduces a new way to characterize the total ionizing dose (TID) responses in the STI oxide. A radiation enhanced drain induced barrier lower (DIBL) effect is observed in the STI parasitic transistor. It is manifested as the drain bias dependence of the radiation-induced off-state leakage and the increase of the DIBL parameter in the STI parasitic transistor after irradiation. Increasing the doping concentration in the whole body region or just near the STI sidewall can increase the threshold voltage of the STI parasitic transistor, and further reduce the radiation-induced off-state leakage. Moreover, we find that the radiation-induced trapped charge in the buried oxide leads to an obvious front-gate threshold voltage shift through the coupling effect. The high doping concentration in the body can effectively suppress the radiation-induced coupling effect. (general)

  14. Response of SIMOX and Unibond buried oxides: trapping and detrapping properties

    International Nuclear Information System (INIS)

    X-ray induced charge trapping and detrapping properties are investigated in SIMOX (separation by implantation of oxygen) and Unibond buried oxides. Irradiation are performed using an Aracor (model 4100) 10 keV X-ray source, under different front and back-gate bias conditions. The back-gate parasitic conduction is recorded, and the Vit and Vot components were extracted from the subthreshold slope by using the standard method of Mc Whorter and Windkur. 4 geometries of transistors are studied in order to check the consistency of the results and no anomalous effect was noticed. A quick comparison of the ΔVot anneal data presented shows that depending on the amount of radiation dose, the variation of the net oxide trapped charge can be very different. At low dose, here 10 krad(SiO2), the evolution of ΔVot is almost not observable until 175 Celsius degrees, whereas at higher doses (from 50 krad(SiO2) on and also for 20 Mrad(SiO2)) the decrease of the net trapped charge is immediate. The authors discuss different possible explanations to this behavior. The data obtained show that even if irradiation results (concerning trapping properties) might look very similar, some differences are observed on the post-irradiation behavior of the 2 materials. (A.C.)

  15. A novel high performance TFS SJ IGBT with a buried oxide layer

    Science.gov (United States)

    Zhang, Jin-Ping; Li, Ze-Hong; Zhang, Bo; Li, Zhao-Ji

    2014-08-01

    A novel high performance trench field stop (TFS) superjunction (SJ) insulated gate bipolar transistor (IGBT) with a buried oxide (BO) layer is proposed in this paper. The BO layer inserted between the P-base and the SJ drift region acts as a barrier layer for the hole-carrier in the drift region. Therefore, conduction modulation in the emitter side of the SJ drift region is enhanced significantly and the carrier distribution in the drift region is optimized for the proposed structure. As a result, compared with the conventional TFS SJ IGBT (Conv-SJ), the proposed BO-SJ IGBT structure possesses a drastically reduced on-state voltage drop (Vce(on)) and an improved tradeoff between Vce(on) and turn-off loss (Eoff), with no breakdown voltage (BV) degraded. The results show that with the spacing between the gate and the BO layer Wo = 0.2 μm, the thickness of the BO layer Lo = 0.2 μm, the thickness of the drift region Ld = 90 μm, the half width and doping concentration of the N- and P-pillars Wn = Wp = 2.5 μm and Nn = Np = 3 × 10 cm-3, the Vce(on) and Eoff of the proposed structure are 1.08 V and 2.81 mJ/cm2 with the collector doping concentration Nc = 1 × 1018 cm-3 and 1.12 V and 1.73 mJ/cm2 with Nc = 5 × 1017 cm-3, respectively. However, with the same device parameters, the Vce(on) and Eoff for the Conv-SJ are 1.81 V and 2.88 mJ/cm2 with Nc = 1 × 1018 cm-3 and 1.98 V and 2.82 mJ/cm2 with Nc = 5 × 10 cm-3, respectively. Meanwhile, the BV of the proposed structure and Conv-SJ are 1414 V and 1413 V, respectively.

  16. Photoluminescence from InGaAs/GaAs quantum well regrown on a buried patterned oxidized AlAs layer

    Science.gov (United States)

    Chouchane, F.; Makhloufi, H.; Calvez, S.; Fontaine, C.; Almuneau, G.

    2014-02-01

    We present a quasi-planar technological approach for forming a flexible and versatile confinement scheme based on oxidation of AlGaAs buried layers combined to an epitaxial regrowth. This method improves the electrical and optical confinements compared to the lateral oxidation since it allows to define confinement areas from a planar surface. This technique is suitable for the realization of advanced integrated photonic components arrays with close device-to-device spacing such as two-dimensional arrays of vertical-cavity surface-emitting lasers. Our results prove that the oxidation and epitaxial regrowth can be sequenced in a process flow, leading to viable confinement while preserving good radiative properties.

  17. Computer simulation for the formation of the insulator layer of silicon-on-insulator devices by N sup + and O sup + Co-implantation

    CERN Document Server

    Lin Qing; Xie Xin Yun; Lin Chenglu; Liu Xiang Hua

    2002-01-01

    A buried sandwiched layer consisting of silicon dioxide (upper part), silicon oxynitride (medium part) and silicon nitride (lower part) is formed by N sup + and O sup + co-implantation in silicon wafers at a constant temperature of 550 degree C. The microstructure is performed by cross-sectional transmission electron microscopy. To predict the quality of the buried sandwiched layer, the authors study the computer simulation for the formation of the SIMON (separated by implantation of oxygen and nitrogen) structure. The simulation program for SIMOX (separated by implantation of oxygen) is improved in order to be applied in O sup + and N sup + co-implantation on the basis of different formation mechanism between SIMOX and SIMNI (separated by implantation of nitrogen) structures. There is a good agreement between experiment and simulation results verifying the theoretical model and presumption in the program

  18. Design and simulation of oxide and doping engineered lateral bipolar junction transistors for high power applications

    Science.gov (United States)

    Loan, Sajad A.; Bashir, Faisal; Akhoon, M. Saqib; Alamoud, Abdulrahman M.

    2016-01-01

    In this paper, we propose new structures of lateral bipolar junction transistor (LBJT) on silicon on insulator (SOI) with improved performance. The proposed devices are lateral bipolar transistors with multi doping zone collector drift region and a thick buried oxide under the collector region. Calibrated simulation studies have revealed that the proposed devices have higher breakdown voltage than the conventional device, that too at higher drift doping concentration. This has resulted in improved tradeoff between the on-resistance and the breakdown voltage of the proposed devices. It has been observed that the proposed device with two collector drift doping zones and a buried oxide thick step results in ∼190% increase in the breakdown voltage than the conventional device. The further increase in the number of collector drift doping zones from two to three has increased the breakdown voltage by 260% than the conventional one. On comparing the proposed devices with the buried oxide double step devices, it has been found that an increase of ∼15-19% in the breakdown voltage is observed in the proposed devices even at higher drift doping concentrations. The use of higher drift doping concentration reduces the on-resistance of the proposed device and thus improves the tradeoff between the breakdown voltage and the on-resistance of the proposed device in comparison to buried oxide double step devices. Further, the use of step doping in the collector drift region has resulted in the reduction of kink effect in the proposed device. Using the mixed mode simulations, the proposed devices have been tested at the circuit level, by designing and simulating inverting amplifiers employing the proposed devices. Both DC and AC analyses of the inverting amplifiers have shown that the proposed devices work well at the circuit level. It has been observed that there is a slight increase in ON delay in the proposed device; however, the OFF delay is more or less same as that of the

  19. Research on total-dose hardening for H-gate PD NMOSFET/SIMOX by ion implanting into buried oxide

    Institute of Scientific and Technical Information of China (English)

    QIAN Cong; ZHANG Zheng-Xuan; ZHANG Feng; LIN Cheng-Lu

    2008-01-01

    In this work,we investigate the back-gate I-V characteristics for two kinds of NMOSFET/SIMOX transistors with H gate structure fabricated on two different SOI wafers.A transistors are made on the wafer implanted with Si+ and then annealed in N2,and B transistors are made on the wafer without implantation and annealing.It is demonstrated experimentally that A transistors have much less back-gate threshold voltage shift AVth than B transistors under X-ray total dose irradiation.Subthreshold charge separation technique is employed to estimate the build-up of oxide charge and interface traps during irradiation,showing that the reduced △Vth for A transistors is mainly due to its less build-up of oxide charge than B transistors.Photoluminescence (PL) research indicates that Si implantation results in the formation of silicon nanocrystalline (nanocluster) whose size increases with the implant dose.This structure can trap electrons to compensate the positive charge build-up in the buried oxide during irradiation,and thus reduce the threshold voltage negative shift.

  20. Research on total-dose hardening for H-gate PD NMOSFET/SIMOX by ion implanting into buried oxide

    International Nuclear Information System (INIS)

    In this work, we investigate the back-gate I-V characteristics for two kinds of NMOSFET/SIMOX transistors with H gate structure fabricated on two different SOI wafers. A transistors are made on the wafer implanted with Si+ and then annealed in N2, and B transistors are made on the wafer without implantation and annealing. It is demonstrated experimentally that A transistors have much less back-gate threshold voltage shift ΔVth than B transistors under X-ray total close irradiation. Subthreshold charge separation technique is employed to estimate the build-up of oxide charge and interface traps during irradiation, showing that the reduced ΔVth for A transistors is mainly due to its less build-up of oxide charge than B transistors. Photo-luminescence (PL) research indicates that Si implantation results in the formation of silicon nanocrystalline (nanocluster) whose size increases with the implant dose. This structure can trap electrons to compensate the positive charge build-up in the buried oxide during irradiation, and thus reduce the threshold voltage negative shift. (authors)

  1. Effect of the technology of implanting nitrogen into buried oxide on the radiation hardness of the top gate oxide for partially depleted SOI PMOSFET

    Institute of Scientific and Technical Information of China (English)

    Zheng Zhong-Shan; Liu Zhong-Li; Zhang Guo-Qiang; Li Ning; Fan Kai; Zhang En-Xia; Yi Wan-Bing; Chen Meng; Wang Xi

    2005-01-01

    The effect of implanting nitrogen into buried oxide on the top gate oxide hardness against total irradiation does has been investigated with three nitrogen implantation doses(8×1015,2×1016 and 1×1017cm -2) for partially depleted SOI PMOSFET.The experimental results reveal the trend of negative shift of the thershold voltages of the studied transistors with the incerase of nitrogen implantation dose before irradition. After the irradiation with a total dose of 5×105 rad (Si)under a positive gate voltage of 2V,the threshold voltage shift of the transistors corresponding to the nitrogen implantation dose 8×1015cm -2 is smaller than that of the transistors without implantation.However, when the implantation dose reaches 2×1016 and 1×1017cm-2, for the majority of the tested transistors,their top gate oxide was badly damaged due to irratiation. In addition, the radiation also causes damage to the body -drain junctions of thetransistors with the gate oxide damaged.All the results can be interpreted by tracing back to the nitrogen implantation damage to the crystal lattices in the top silicon.

  2. Methods for precisely controlling the residual stress and temperature coefficient of the frequency of a MEMS resonator based on an AlN cavity silicon-on-insulator platform

    Science.gov (United States)

    Wang, Nan; Xu, Jinghui; Zhang, Xiaolin; Wu, Guoqiang; Zhu, Yao; Li, Wei; Gu, Yuandong

    2016-07-01

    In this paper, we report an experimentally verified numerical model developed for precisely predicting and controlling the initial bending of a multi-layer-stack composite cantilever structure which is caused by the residual stress of the individual constituting layers, as well as the cantilever’s thermal coefficient of frequency (TCF). The developed model is exemplified using a flexural-mode cantilever resonator according to the process flow of the aluminium nitride (AlN) cavity silicon-on-insulator (SOI) platform. The same AlN cavity SOI platform is also utilized to fabricate the exemplified cantilever, which is then used to experimentally verify the accuracy and consistency of the numerical model. The experimental results show a difference of less than 3.5% is observed in terms of the deflection at the tip of the cantilever as compared with the numerical model, demonstrating the accuracy of the developed numerical model and the feasibility to optimize the cantilever’s initial deflection and TCF simultaneously, achieving minimum values for both parameters at the same time.

  3. Depth- and momentum- resolved electronic structure at buried oxide interfaces from standing-wave angle-resolved photoemission

    Science.gov (United States)

    Fadley, Charles

    2015-03-01

    It is clear that interfaces in complex oxide heterostructures often represent emergent materials that possess surprising properties not associated with the parent oxides, such as two-dimensional electron gases (2DEGs), superconductivity, and magnetism. A detailed knowledge of the composition, atomic structure, and electronic structure through such interfaces is thus critical. Photomission (PES) and angle-resolved photoemission (ARPES) represent techniques of choice for such studies, but have certain limitations in being too surface sensitive and in not being able to focus specifically on buried interfaces or heterostructure layers. In this talk, I will discuss combining two newer elements of PES/ARPES to deal with this challenge: - the use of soft x-rays in the ca. few hundred-to-2000 eV regime, or even into the true hard x-ray regime, to probe more deeply into the structure, and - tailoring of the x-ray intensity profile into a strong standing wave (SW) through reflection from a multilayer heterostructure to provide much enhanced depth resolution. The relative advantages of soft/hard x-ray PES and ARPES and their complementarity to conventional VUV ARPES in the ca. 5-150 eV regime will be considered. As illustrative examples, by combining SW-PES and SW-ARPES, it has been possible to measure for the first time the detailed concentration profiles and momentum-resolved electronic structure at the SrTiO3/La0.67Sr0.33MnO3 interface and to directly measure the depth profile of the 2DEG at SrTiO3/GdTiO3 interfaces. Future directions for such measurements will also be discussed. Supported by US DOE Contract No. DE-AC02-05CH11231, ARO-MURI Grant W911-NF-09-1-0398, and the PALM-APTCOM Project (France).

  4. Transparent electrodes for high E-field production using a buried indium tin oxide layer

    Science.gov (United States)

    Gunton, Will; Polovy, Gene; Semczuk, Mariusz; Madison, Kirk W.

    2016-03-01

    We present a design and characterization of optically transparent electrodes suitable for atomic and molecular physics experiments where high optical access is required. The electrodes can be operated in air at standard atmospheric pressure and do not suffer electrical breakdown even for electric fields far exceeding the dielectric breakdown of air. This is achieved by putting an indium tin oxide coated dielectric substrate inside a stack of dielectric substrates, which prevents ion avalanche resulting from Townsend discharge. With this design, we observe no arcing for fields of up to 120 kV/cm. Using these plates, we directly verify the production of electric fields up to 18 kV/cm inside a quartz vacuum cell by a spectroscopic measurement of the dc Stark shift of the 52S1/2 → 52P3/2 transition for a cloud of laser cooled rubidium atoms. We also report on the shielding of the electric field and on the residual electric fields that persist within the vacuum cell once the electrodes are discharged. In addition, we discuss observed atom loss that results from the motion of free charges within the vacuum. The observed asymmetry of these phenomena on the bias of the electrodes suggests that field emission of electrons within the vacuum is primarily responsible for these effects and may indicate a way of mitigating them.

  5. A Novel Nanoscale FDSOI MOSFET with Block-Oxide

    OpenAIRE

    Jyi-Tsong Lin; Yi-Chuen Eng; Po-Hsieh Lin

    2013-01-01

    We demonstrate improved device performance by applying oxide sidewall spacer technology to a block-oxide-enclosed Si body to create a fully depleted silicon-on-insulator (FDSOI) nMOSFET, which overcomes the need for a uniform ultrathin silicon film. The presence of block-oxide along the sidewalls of the Si body significantly reduces the influence of drain bias over the channel. The proposed FDSOI structure therefore outperforms conventional FDSOI with regard to its drain-induced barrier lower...

  6. Silicon on Insulator MESFETs for RF Amplifiers.

    Science.gov (United States)

    Wilk, Seth J; Balijepalli, Asha; Ervin, Joseph; Lepkowski, William; Thornton, Trevor J

    2010-03-01

    CMOS compatible, high voltage SOI MESFETs have been fabricated using a standard 3.3V CMOS process without any changes to the process flow. A 0.6μm gate length device operates with a cut-off frequency of 7.3GHz and a maximum oscillation frequency of 21GHz. There is no degradation in device performance up to its breakdown voltage, which greatly exceeds that of CMOS devices on the same process. Other figures of merit of relevance to RF front-end design are presented, including the maximum stable gain and noise figure. An accurate representation of the device in SPICE has been developed using the commercially available TOM3 model. Using the SOI MESFET model, a source degenerated low noise RF amplifier targeting operation near 1GHz has been designed. The amplifier was fabricated on a PCB board and operates at 940MHz with a minimum NF of 3.8dB and RF gain of 9.9dB while only consuming 5mW of DC power. PMID:20657816

  7. Permittivity of oxidized ultra-thin silicon films from atomistic simulations

    OpenAIRE

    Penazzi, G.; KWOK, YH; Aradi, B.; Pecchia, A.; Frauenheim, T.; Chen, G.; Markov, SN

    2015-01-01

    We establish the dependence of the permittivity of oxidized ultra-thin silicon films on the film thickness by means of atomistic simulations within the density-functional-based tight-binding theory (DFTB). This is of utmost importance for modeling ultra- and extremely-thin silicon-on-insulator MOSFETs, and for evaluating their scaling potential. We demonstrate that electronic contribution to the dielectric response naturally emerges from the DFTB Hamiltonian when coupled to Poisson equation s...

  8. Response of SIMOX and Unibond buried oxides: trapping and detrapping properties; Sensibilite des oxydes enterres SIMOX et Unibond: proprietes de piegeage et de depiegeage

    Energy Technology Data Exchange (ETDEWEB)

    Paillet, P.; Ferlet-Cavrois, V. [CEA Bruyeres-le-Chatel, 91 (France); Schwank, J.R.; Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States)

    1999-07-01

    X-ray induced charge trapping and detrapping properties are investigated in SIMOX (separation by implantation of oxygen) and Unibond buried oxides. Irradiation are performed using an Aracor (model 4100) 10 keV X-ray source, under different front and back-gate bias conditions. The back-gate parasitic conduction is recorded, and the V{sub it} and V{sub ot} components were extracted from the subthreshold slope by using the standard method of Mc Whorter and Windkur. 4 geometries of transistors are studied in order to check the consistency of the results and no anomalous effect was noticed. A quick comparison of the {delta}V{sub ot} anneal data presented shows that depending on the amount of radiation dose, the variation of the net oxide trapped charge can be very different. At low dose, here 10 krad(SiO{sub 2}), the evolution of {delta}V{sub ot} is almost not observable until 175 Celsius degrees, whereas at higher doses (from 50 krad(SiO{sub 2}) on and also for 20 Mrad(SiO{sub 2})) the decrease of the net trapped charge is immediate. The authors discuss different possible explanations to this behavior. The data obtained show that even if irradiation results (concerning trapping properties) might look very similar, some differences are observed on the post-irradiation behavior of the 2 materials. (A.C.)

  9. Buried Waste Integrated Demonstration

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a suite of advanced technologies that offer promising solutions to the problems associated with the remediation of buried waste. BWID addresses the difficult remediation problems associated with DOE complex-wide buried waste, particularly transuranic (TRU) contaminated buried waste. BWID has implemented a systems approach to the development and demonstration of technologies that will characterize, retrieve, treat, and dispose of DOE buried wastes. This approach encompasses the entire remediation process from characterization to post-monitoring. The development and demonstration of the technology is predicated on how a technology fits into the total remediation process. To address all of these technological issues, BWID has enlisted scientific expertise of individuals and groups from within the DOE Complex, as well as experts from universities and private industry. The BWID mission is to support development and demonstration of a suite of technologies that, when integrated with commercially-available technologies, forms a comprehensive, remediation system for the effective and efficient remediation of buried waste throughout the DOE Complex. BWID will evaluate and validate demonstrated technologies and transfer this information and equipment to private industry to support the Office of Environmental Restoration (ER), Office of Waste Management (WM), and Office of Facility Transition (FT) remediation planning and implementation activities

  10. Remote technologies for buried waste retrieval

    International Nuclear Information System (INIS)

    The DOE is evaluating what should be done with this buried waste. Although the radioactive waste is not particularly mobile unless airborne, some of it was buried with volatile organics and/or other substances that tend to spread easily to surrounding soil or water tables. Volatile organics are hazardous materials (such as trichloroethylene) and require clean-up at certain levels in drinking water. There is concern that the buried volatile organics will spread into the water table and contaminate drinking water. Because of this, the DOE is considering options for handling this buried waste and reducing the risks of spreading or exposure. There are two primary options: containment and stabilization, or retrieval. Containment and stabilization systems would include systems that would leave the waste where it is, but contain and stabilize it so that the radioactive and hazardous materials would not spread to the surrounding soil, water, or air. For example, an in situ vitrification system could be used to melt the waste into a composite glass-like material that would not leach into the surrounding soil, water, or air. Retrieval systems are those that would remove the waste from its burial location for treatment and/or repackaging for long term storage. The objective of this project was to develop and demonstrate remote technologies that would minimize dust generation and the spread of airborne contaminants during buried waste retrieval. Remote technologies are essential for the retrieval of buried waste because they remove workers from the hazardous environment and provide greater automation, reducing the chances of human error. Minimizing dust generation is also essential to increased safety for the workers and the environment during buried waste retrieval. The main contaminants within the waste are micron-sized particles of plutonium and americium oxides, chlorides, and hydroxides, which are easily suspended in air and spread if disturbed

  11. Understanding the role of buried Si/SiO2 interface on dopant and defect evolution in PAI USJ

    International Nuclear Information System (INIS)

    For CMOS technology, generations beyond the 65 nm node a major goal is achieving highly activated, ultra-shallow and abrupt profiles. In the case of p-type (boron) implants, one method to achieve this is using Ge preamorphization (PAI) prior to ultra-low energy B implantation. However, for future technology nodes, new issues arise when bulk silicon is supplanted by silicon-on-insulator (SOI). Understanding the strong impact of the buried Si/SiO2 interface, will enable tests of fundamental models on defect evolution, electrical activation and diffusion. In the present study, boron has been implanted in germanium-preamorphized silicon and SOI wafers. Subsequent to implantation, an isochronal and isothermal annealing study of the samples was carried out. Electrical and structural properties were measured by Hall effect and SIMS techniques. The results show a range of effects in both substrate types, including TED and deactivation driven by interstitials from the end-of-range (EOR) defects. However, in the SOI material there is a lower boron deactivation and the EOR defects are eliminated at a lower thermal budget in SOI than in the bulk silicon due to competition between the upper SOI interface and the Si surface which both act as sinks for interstitials

  12. PbS quantum dots - silicon on insulator hybrid photonics

    International Nuclear Information System (INIS)

    Full text: We investigate the optical properties of colloidal PbS quantum dots (QDs) as active materials for all integrated silicon photonic structures like waveguides and ring resonators at 300 K. Dissolving the QDs into a polymer resist enables on-chip integration using lithographic patterning and allows a precise control of the QD concentration in the polymer. The photoluminescence from the resonating modes at the output of the waveguide as well as the waveguide–resonator coupling and the cavity quality factors are studied as function of the QD concentration in the polymer. Our method additionally allows investigations of the cavity-modified optical properties of PbS QDs. (author)

  13. DAQ Development for Silicon-On-Insulator Pixel detectors

    CERN Document Server

    Nishimura, Ryutaro; Miyoshi, Toshinobu

    2015-01-01

    We are developing DAQ for Si-pixel detectors by using a Slicon-On-Insulator (SOI) technology. This DAQ consists of firmware works on SEABAS (Soi EvAluation BoArd with Sitcp) DAQ board and software works on PC. We have been working on the development of firmware/software. Now we accomplished to speed up the readout (~90Hz) and to add a function for frame rate control. This is the report of our development work for the High Speed DAQ system.

  14. Silicon-on-insulator polarization controller with relaxed fabrication tolerances

    OpenAIRE

    Sarmiento-Merenguel, J.D; Alonso-Ramos, C.; Halir, R.; L. Vivien; Cheben, P.; Ortega Moñux, Alejandro; Molina-Fernández, I; Leroux, X.; Marris-Morini, D.; Xu, D.X.; Schmid, J. H.; Janz, S.

    2014-01-01

    Polarization control is essential in applications ranging from optical communications to interferometric sensors. The implementation of in- tegrated polarization controllers is challenging as they require polariza- tion rotating waveguides with stringent fabrication tolerances. Here, we present a fully integrated polarization controller scheme that signi cantly relaxes the requirements on the rotating waveguides, alleviating fabri- cation tolerances. We analytically establis...

  15. Energetic, spatial, and momentum character of the electronic structure at a buried interface: The two-dimensional electron gas between two metal oxides

    Science.gov (United States)

    Nemšák, S.; Conti, G.; Gray, A. X.; Palsson, G. K.; Conlon, C.; Eiteneer, D.; Keqi, A.; Rattanachata, A.; Saw, A. Y.; Bostwick, A.; Moreschini, L.; Rotenberg, E.; Strocov, V. N.; Kobayashi, M.; Schmitt, T.; Stolte, W.; Ueda, S.; Kobayashi, K.; Gloskovskii, A.; Drube, W.; Jackson, C. A.; Moetakef, P.; Janotti, A.; Bjaalie, L.; Himmetoglu, B.; Van de Walle, C. G.; Borek, S.; Minar, J.; Braun, J.; Ebert, H.; Plucinski, L.; Kortright, J. B.; Schneider, C. M.; Balents, L.; de Groot, F. M. F.; Stemmer, S.; Fadley, C. S.

    2016-06-01

    The interfaces between two condensed phases often exhibit emergent physical properties that can lead to new physics and novel device applications and are the subject of intense study in many disciplines. We here apply experimental and theoretical techniques to the characterization of one such interesting interface system: the two-dimensional electron gas (2DEG) formed in multilayers consisting of SrTi O3 (STO) and GdTi O3 (GTO). This system has been the subject of multiple studies recently and shown to exhibit very high carrier charge densities and ferromagnetic effects, among other intriguing properties. We have studied a 2DEG-forming multilayer of the form [6unit cells (u .c .) STO /3 u .c .of GTO ] 20 using a unique array of photoemission techniques including soft and hard x-ray excitation, soft x-ray angle-resolved photoemission, core-level spectroscopy, resonant excitation, and standing-wave effects, as well as theoretical calculations of the electronic structure at several levels and of the actual photoemission process. Standing-wave measurements below and above a strong resonance have been exploited as a powerful method for studying the 2DEG depth distribution. We have thus characterized the spatial and momentum properties of this 2DEG in detail, determining via depth-distribution measurements that it is spread throughout the 6 u.c. layer of STO and measuring the momentum dispersion of its states. The experimental results are supported in several ways by theory, leading to a much more complete picture of the nature of this 2DEG and suggesting that oxygen vacancies are not the origin of it. Similar multitechnique photoemission studies of such states at buried interfaces, combined with comparable theory, will be a very fruitful future approach for exploring and modifying the fascinating world of buried-interface physics and chemistry.

  16. Scheme for the fabrication of ultrashort channel metal-oxide-semiconductor field-effect transistors

    International Nuclear Information System (INIS)

    We present a scheme for the fabrication of ultrashort channel length metal-oxide-semiconductor field-effect transistors (MOSFETs) involving nanolithography and molecular-beam epitaxy. The active channel is undoped and is defined by a combination of nanometer-scale patterning and anisotropic etching of an n++ layer grown on a silicon on insulator wafer. The method is self-limiting and can produce MOSFET devices with channel lengths of less than 10 nm. Measurements on the first batch of n-MOSFET devices fabricated with this approach show very good output characteristics and good control of short-channel effects. (c) 2000 American Institute of Physics

  17. Failure analysis of buried tanks

    International Nuclear Information System (INIS)

    Failure of a buried tank can be hazardous. Failure may be a leak through which product is lost from the tank; but also through which contamination can occur. Failures are epidemic -- because buried tanks are out of sight, but also because designers of buried tanks have adopted analyses developed for pressure tanks. So why do pressure tanks fail when they are buried? Most failures of buried tanks are really soil failures. Soil compresses, or slips, or liquefies. Soil is not only a load, it is a support without which the tank deforms. A high water table adds to the load on the tank. It also reduces the strength of the soil. Based on tests, structural analyses are proposed for empty tanks buried in soils of various quality, with the water table at various levels, and with internal vacuum. Failure may be collapse tank. Such collapse is a sudden, audible inversion of the cylinder when the sidefill soil slips. Failure may be flotation. Failure may be a leak. Most leaks are fractures in the welds in overlap seams at flat spots. Flat spots are caused by a hard bedding or a heavy surface wheel load. Because the tank wall is double thick at the overlap, shearing stress in the weld is increased. Other weld failures occur when an end plate shears down past a cylinder; or when the tank is supported only at its ends like a beam. These, and other, failures can be analyzed with justifiable accuracy using basic principles of mechanics of materials. 10 figs

  18. A Novel Nanoscale FDSOI MOSFET with Block-Oxide

    Directory of Open Access Journals (Sweden)

    Jyi-Tsong Lin

    2013-01-01

    Full Text Available We demonstrate improved device performance by applying oxide sidewall spacer technology to a block-oxide-enclosed Si body to create a fully depleted silicon-on-insulator (FDSOI nMOSFET, which overcomes the need for a uniform ultrathin silicon film. The presence of block-oxide along the sidewalls of the Si body significantly reduces the influence of drain bias over the channel. The proposed FDSOI structure therefore outperforms conventional FDSOI with regard to its drain-induced barrier lowering (DIBL, on/off current ratio, subthreshold swing, and threshold voltage rolloff. The new FDSOI structure is in fact shown to behave similarly to an ultrathin body (UTB SOI but without the associated disadvantages and technological challenges of the ultrathin film, because a thick Si body allows for reduced sensitivity to self-heating, thereby improving thermal stability.

  19. Quantitative Chemically-Specific Coherent Diffractive Imaging of Buried Interfaces using a Tabletop EUV Nanoscope

    CERN Document Server

    Shanblatt, Elisabeth R; Gardner, Dennis F; Mancini, Giulia F; Karl, Robert M; Tanksalvala, Michael D; Bevis, Charles S; Vartanian, Victor H; Kapteyn, Henry C; Adams, Daniel E; Murnane, Margaret M

    2016-01-01

    Characterizing buried layers and interfaces is critical for a host of applications in nanoscience and nano-manufacturing. Here we demonstrate non-invasive, non-destructive imaging of buried interfaces using a tabletop, extreme ultraviolet (EUV), coherent diffractive imaging (CDI) nanoscope. Copper nanostructures inlaid in SiO2 are coated with 100 nm of aluminum, which is opaque to visible light and thick enough that neither optical microscopy nor atomic force microscopy can image the buried interfaces. Short wavelength (29 nm) high harmonic light can penetrate the aluminum layer, yielding high-contrast images of the buried structures. Moreover, differences in the absolute reflectivity of the interfaces before and after coating reveal the formation of interstitial diffusion and oxidation layers at the Al-Cu and Al-SiO2 boundaries. Finally, we show that EUV CDI provides a unique capability for quantitative, chemically-specific imaging of buried structures, and the material evolution that occurs at these buried ...

  20. Ultrasonic isolation of buried pipes

    Science.gov (United States)

    Leinov, Eli; Lowe, Michael J. S.; Cawley, Peter

    2016-02-01

    Long-range guided wave testing (GWT) is used routinely for the monitoring and detection of corrosion defects in above ground pipelines. The GWT test range in buried, coated pipelines is greatly reduced compared to above ground configurations due to energy leakage into the embedding soil. In this paper, the effect of pipe coatings on the guided wave attenuation is investigated with the aim of increasing test ranges for buried pipelines. The attenuation of the T(0,1) and L(0,2) guided wave modes is measured using a full-scale experimental apparatus in a fusion-bonded epoxy (FBE)-coated 8 in. pipe, buried in loose and compacted sand. Tests are performed over a frequency range typically used in GWT of 10-35 kHz and compared with model predictions. It is shown that the application of a low impedance coating between the FBE layer and the sand effectively decouples the influence of the sand on the ultrasound leakage from the buried pipe. Ultrasonic isolation of a buried pipe is demonstrated by coating the pipe with a Polyethylene (PE)-foam layer that has a smaller impedance than both the pipe and sand, and has the ability to withstand the overburden load from the sand. The measured attenuation in the buried PE-foam-FBE-coated pipe is found to be substantially reduced, in the range of 0.3-1.2 dB m-1 for loose and compacted sand conditions, compared to measured attenuation of 1.7-4.7 dB m-1 in the buried FBE-coated pipe without the PE-foam. The acoustic properties of the PE-foam are measured independently using ultrasonic interferometry and incorporated into model predictions of guided wave propagation in buried coated pipe. Good agreement is found between the experimental measurements and model predictions. The attenuation exhibits periodic peaks in the frequency domain corresponding to the through-thickness resonance frequencies of the coating layer. The large reduction in guided wave attenuation for PE-coated pipes would lead to greatly increased GWT test ranges; such

  1. BURIED COMPONENTS OF A JULIA SET

    Institute of Scientific and Technical Information of China (English)

    SunYeshun; YangChungchun

    2002-01-01

    In this note,it is shown that if a rational function fofdegree≥2 has a nonempty set of buried points ,then for a generic choice of the point z in the Julia set ,z is a buried point ,and if the Julia set is disconnected,it has uncountably many buried components.

  2. Dispersion study of buried elemental mercury

    International Nuclear Information System (INIS)

    Waste elemental mercury disposed of by burial in trenches has been found to have no probable environmental effects. (This method of disposal has been discontinued.) Transport modes by which buried mercury would be expected to reach man in the environment were modeled mathematically using experimentally determined and estimated parameters. Calculations established that elemental mercury is the stable chemical form in the soil matrix. Consequently, only diffusion of mercury vapor to the atmosphere and transport of mercury in soil water to the water table merited consideration. Aqueous transport occurs by both dissolution of mercury in water (maximum = 57 ppB) and suspension of mercury on oxide colloids of iron and silicon in soil water

  3. Impact of SOI substrate on the radiation response of ultrathin transistors down to the 20 nm node

    International Nuclear Information System (INIS)

    In this paper we investigate the Total Ionizing Dose (TID) response of an Ultra Thin Buried-Oxide (UTBOX) on a Fully Depleted Silicon-On-Insulator (FDSOI) high-k/metal gate technology. The impact of thinning the BOX and of the use of a Ground Plane (GP) at the back side of the BOX on the TID behavior are discussed by comparing their results to ionizing radiation experiments performed on reference FDSOI devices. (authors)

  4. Theory buried under heavy description

    Directory of Open Access Journals (Sweden)

    Vivian B. Martin Ph.D.

    2010-12-01

    Full Text Available In journalism when a reporter puts the main news or point of the story deep down in the text, we say she’s buried the lead, the lead being the main point of the story and usually the first paragraph. In Children in Genocide: extreme traumatization and affect regulation, psychoanalyst Suzanne Kaplan buries her theory. Her study of the after effects of trauma among Holocaust survivors who were children during their persecution and survivors of atrocities during the Rwandan atrocities of the 1990s, is filled with highly descriptive material from the many interviews that serve as data. An interesting grounded theory is peeking out from under all the disciplinary discourse and historical background one must read through to get to what grounded theory readers will consider the juicy parts: concepts on affect regulation in trauma survivors.

  5. Design of buried concrete encasements

    International Nuclear Information System (INIS)

    The operation of many Department of Energy (DOE) sites requires the transfer of radioactive liquid products from one location to another. DOE Order 6430.1A requires that the transfer pipelines be designed and constructed so that any leakage can be detected and contained before it reaches the environment. One design option often considered to meet this requirement is to place the pipeline in a stainless steel-lined, buried concrete encasement. This provides the engineer with the design challenge to integrate standard structural design principles with unique DOE requirements. The complete design of a buried concrete encasement must consider seismic effects, leak detection, leak confinement, radiation shielding, thermal effects, pipe supports, and constructability. This paper contains a brief discussion of each of these design considerations, based on experience gained during the design of concrete encasements for the Process Facilities Modifications (PFM) project at Hanford

  6. Approaches of Buried Object Detection Technology

    OpenAIRE

    Nagashree R N; Aswini N

    2014-01-01

    This paper describes the different art of buried object detection technology and algorithms. This detection of buried object finds application in many areas, importantly in the Landmine detection which is of growing concern due to the danger of buried landmines to people’s lives, economic growth and development. This paper describes and analyzes different technology available. The approaches discussed are Electrical Impedance Tomography, X-ray backscatter, Infrared Systems, Acoustics/seismic ...

  7. Buried Waste Integrated Demonstration Plan

    International Nuclear Information System (INIS)

    This document presents the plan of activities for the Buried Waste Integrated Demonstration (BWID) program which supports the environmental restoration (ER) objectives of the Department of Energy (DOE) Complex. Discussed in this plan are the objectives, organization, roles and responsibilities, and the process for implementing and managing BWID. BWID is hosted at the Idaho National Engineering Laboratory (INEL), but involves participants from throughout the DOE Complex, private industry, universities, and the international community. These participants will support, demonstrate, and evaluate a suite of advanced technologies representing a comprehensive remediation system for the effective and efficient remediation of buried waste. The processes for identifying technological needs, screening candidate technologies for applicability and maturity, selecting appropriate technologies for demonstration, field demonstrating, evaluation of results and transferring technologies to environmental restoration programs are also presented. This document further describes the elements of project planning and control that apply to BWID. It addresses the management processes, operating procedures, programmatic and technical objectives, and schedules. Key functions in support of each demonstration such as regulatory coordination, safety analyses, risk evaluations, facility requirements, and data management are presented

  8. Inspection device for buried equipment

    International Nuclear Information System (INIS)

    In an inspection device for a buried equipment, a rail is suspended at the upper portion of a vessel of a pit-vessel type pump buried in a plant building floor, and a truck movable vertical in the vessel along the rail, and an ultrasonic wave probe contained in the truck and urged to the vessel by an electromagnet are disposed. In addition, an elevator moving vertically along a shaft is disposed, and an arm having the ultrasonic probe disposed at the end portion and driven by a piston are disposed to the elevator. The ultrasonic wave probe moves vertically together with the truck along the rail in the vessel while being urged to the vessel by the electromagnet to inspect and measure the state at the inner and outer surfaces of the vessel. Further, the length of the arm is controlled so as to set a predetermined distance between the ultrasonic wave probe and the vessel. Subsequently, the elevator is moved vertically along a shaft passing through a shaft hole of a mount, and the shaft is rotated thereby enabling to inspect and measure the state of the inner and outer surfaces of the vessel. (N.H.)

  9. Chemical detection of buried landmines

    Energy Technology Data Exchange (ETDEWEB)

    Phelan, J.M.; Webb, S.W.

    1998-03-01

    Of all the buried landmine identification technologies currently available, sensing the chemical signature from the explosive components found in landmines is the only technique that can classify non-explosive objects from the real threat. In the last two decades, advances in chemical detection methods has brought chemical sensing technology to the foreground as an emerging technological solution. In addition, advances have been made in the understanding of the fundamental transport processes that allow the chemical signature to migrate from the buried source to the ground surface. A systematic evaluation of the transport of the chemical signature from inside the mine into the soil environment, and through the soil to the ground surface is being explored to determine the constraints on the use of chemical sensing technology. This effort reports on the results of simulation modeling using a one-dimensional screening model to evaluate the impacts on the transport of the chemical signature by variation of some of the principal soil transport parameters.

  10. Mining metrics for buried treasure

    CERN Document Server

    Konkowski, D A

    2004-01-01

    The same but different: That might describe two metrics. On the surface CLASSI may show two metrics are locally equivalent, but buried beneath one may be a wealth of further structure. This was beautifully describeed in a paper by M.A.H. MacCallum in 1998. Here I will illustrate the effect with two flat metrics -- one describing ordinary Minkowski spacetime and the other describing a three-parameter family of Gal'tsov-Letelier-Tod spacetimes. I will dig out the beautiful hidden classical singularity structure of the latter (a structure first noticed by Tod in 1994) and then show how quantum considerations can illuminate the riches. I will then discuss how quantum structure can help us understand classical singularities and metric parameters in a variety of exact solutions mined from the Exact Solutions book.

  11. Asymmetric Gate Oxide Thickness Technology for Reduction of Gate Induced Drain Leakage Current in Nanoscale Single Gate SOI MOSFET

    Directory of Open Access Journals (Sweden)

    Zahara Ahangari

    2009-06-01

    Full Text Available Gate Induced Drain Leakage (GIDL current is one of the main leakage current components in Silicon on Insulator (SOI MOSFET structure and plays an important role in the data retention time of DRAM cells. GIDL can dominate the drain leakage current at zero bias and will limit the scalability of the structure for low power applications. In this paper we propose a novel technique for reducing GIDL and hence off-state current in the nanoscale single gate SOI MOSFET structure. The proposed structure employs asymmetric gate oxide thickness which can reduce GIDL current and hence Ioff current to about 98% in comparison with the symmetric gate oxide thickness structure, without sacrificing the driving current and losing gate control over the channel. This technique is very simple in the fabrication point of view in CMOS technology.

  12. A 200 V silicon-on-sapphire LDMOS structure with a step oxide extended field plate

    Science.gov (United States)

    Roig, J.; Flores, D.; Rebollo, J.; Hidalgo, S.; Millan, J.

    2004-02-01

    Fabrication of power integrated circuits on silicon-on-sapphire (SOS) substrates has rarely been considered before. Hence, there is a lack of research in lateral power devices integrated on SOS. Self-heating effects in existing silicon-on-insulator (SOI) lateral power devices degrade the device performance and their reliability. Use of SOS substrates could alleviate these problems though they would require a different approach in lateral power device engineering. This paper purposes a new power SOS LDMOS structure with reduced transient self-heating effects and enhanced current capability compared to the conventional SOI counterpart. The proposed lateral power structure integrated on SOS substrates is analyzed by electro-thermal simulations. The field plate is enlarged (extended field plate (EFP)) along the drift region, reaching the drain region. The EFP includes an oxide step which improves the "on-state resistance-breakdown voltage" trade-off ( RONxS- Vbr).

  13. Signature of a buried supernova

    International Nuclear Information System (INIS)

    We study the sturcture and emission of a supernova remnant embedded in a dense molecular cloud, deferring a study of O-star progenitor effects to a later paper. During the early life of the remnant, grain emission from the interior produces an infrared maximum. At later stages, the X-rays from the hot interior create a region of warm, partially ionized gas outside the shell, in which most of the luminosity is reprocessed by grains into far-infrared radiation. The pulsar left as a remnant of the explosion can deposit an energy comparable to the initial explosion in a time that is short compared to the shell-formation time t/sub sg/. For an ambient density n/sub i/=105 cm-3, the initial infrared flash of approx.2.5 x 108 L/sub sun/ is followed by a secondary luminosity peak of approx.107 L/sub sun/ after a time t/sub sg/approx. =20 yr and fades thereafter as (t/t/sub sg/)/sup -8/7/. Such remnants should be detectable in our Galaxy with current technology and in external galaxies with the planned IRAS or Shuttle Infrared Telescopes. A sizable number of buried supernovae could resolve the apparent discrepancy between pulsar and supernova birthrates

  14. Approaches of Buried Object Detection Technology

    Directory of Open Access Journals (Sweden)

    Nagashree R N

    2014-03-01

    Full Text Available This paper describes the different art of buried object detection technology and algorithms. This detection of buried object finds application in many areas, importantly in the Landmine detection which is of growing concern due to the danger of buried landmines to people’s lives, economic growth and development. This paper describes and analyzes different technology available. The approaches discussed are Electrical Impedance Tomography, X-ray backscatter, Infrared Systems, Acoustics/seismic systems; Neutron based Method and finally Ground-Penetrating Radar with two commonly available approaches: Least squares and SVD approach. Finally, the paper concludes highlighting the need to improve the way this information is processed and compared.

  15. Tabernaemontana divaricata leaves extract exacerbate burying behavior in mice

    Directory of Open Access Journals (Sweden)

    Raj Chanchal

    2015-06-01

    Full Text Available Objective: Tabernaemontana divaricata (TD from Apocynaceae family offers the traditional folklore medicinal benefits such as an anti-epileptic, anti-mania, brain tonic, and anti-oxidant. The aim of the present study was to evaluate the effect of ethanolic extract of TD leaves on burying behavior in mice. Materials and Methods:Mice were treated with oral administration (p.o. of ethanolic extract of TD (100, 200, and 300 mg/kg. Fluoxetine (FLX, a selective serotonin reuptake inhibitor was used as a reference drug. Obsessive-compulsive behavior was evaluated using marble-burying apparatus. Results:TD at doses of 100, 200, and 300 mg/kg dose-dependently inhibited the obsessive and compulsive behavior. The similar results were obtained from 5, 10, and 20 mg/kg of FLX. TD and FLX did not affect motor activity. Conclusion: The results indicated that TD and FLX produced similar inhibitory effects on marble-burying behavior.

  16. Biodegradation of additive PHBV/PP-co-PE films buried in soil

    Directory of Open Access Journals (Sweden)

    Barbara Rani-Borges

    2016-01-01

    Full Text Available Abstract There is considerable concern about the impact plastic materials have on the environment due to their durability and resistance to degradation. The use of pro-oxidant additives in the polymer films could be a viable way to decrease the harmful effects of these discarded materials. In this study, films of PHBV/PP-co-PE (80/20 w/w and PHBV/PP-co-PE/add (80/19/1 w/w/w (with pro-oxidant additive were employed to verify the influence of the additive on the biodegradation of these films in the soil. These films were obtained by melting the pellets in a press at 180 °C which were buried in soil columns for 3 and 6 months. Some samples were also heated before being buried in soil. The biodegradation is higher for the additive blend buried for 3 months than for the pre-heated blend. After 6 months the blend buried and heated/buried was completely degraded in soil. The effect of the additive, on chain oxidation, is more time-dependant than heat-dependant.

  17. American burying beetle site records : Valentine NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is specific site records of American burying beetle on Valentine Nationl Wildlife Refuge to date. It includes a map of site location. A discussion...

  18. TNX Burying Ground: Environmental information document

    International Nuclear Information System (INIS)

    The TNX Burying Ground, located within the TNX Area of the Savannah River Plant (SRP), was originally built to dispose of debris from an experimental evaporator explosion at TNX in 1953. This evaporator contained approximately 590 kg of uranyl nitrate. From 1980 to 1984, much of the waste material buried at TNX was excavated and sent to the SRP Radioactive Waste Burial Grounds for reburial. An estimated 27 kg of uranyl nitrate remains buried at TNX. The TNX Burying Ground consists of three sites known to contain waste and one site suspected of containing waste material. All four sites are located within the TNX security fenceline. Groundwater at the TNX Burying Ground was not evaluated because there are no groundwater monitoring wells installed in the immediate vicinity of this waste site. The closure options considered for the TNX Burying Ground are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated

  19. TNX Burying Ground: Environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Dunaway, J.K.W.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.

    1987-03-01

    The TNX Burying Ground, located within the TNX Area of the Savannah River Plant (SRP), was originally built to dispose of debris from an experimental evaporator explosion at TNX in 1953. This evaporator contained approximately 590 kg of uranyl nitrate. From 1980 to 1984, much of the waste material buried at TNX was excavated and sent to the SRP Radioactive Waste Burial Grounds for reburial. An estimated 27 kg of uranyl nitrate remains buried at TNX. The TNX Burying Ground consists of three sites known to contain waste and one site suspected of containing waste material. All four sites are located within the TNX security fenceline. Groundwater at the TNX Burying Ground was not evaluated because there are no groundwater monitoring wells installed in the immediate vicinity of this waste site. The closure options considered for the TNX Burying Ground are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated.

  20. Effects of buried penis on the structure and function of corpus cavernosum in a rat model

    Institute of Scientific and Technical Information of China (English)

    CHENG Fan; YU Wei-min; XIA Yue; ZHANG Xiao-bin; YANG Si-xing; GE Ming-huan

    2010-01-01

    Background While the abnormal appearance of the concealed penis has been well recognized, the effect of buried penis on the structure and function of corpus cavernosum has not been well studied. To explore this issue, we established a rat model and evaluated the effect of buried penis on cavernosum weight, contents and ultrastructure of tissue, and nitric oxide synthase (NOS) activity.Methods Two hundred and ten rats were randomly divided into 3 equal cohorts for 2, 4 and 6 months study (groups A, B and C). Each group was randomly divided into buried group (n=40), control group (n=15), and normal group (n=15), respectively. Intra-purse-string suture of the root of the penis was used to establish the model. Macroscopic development was judged by measuring the weight of the corpus cavernosum. Masson's trichrome staining was performed for observing microstructure while a transmission electron microscope was used for observing ultrastructure. The NOS activity was detected by a NOS activity assay kit.Results Buried penis had no significant influence on the appearance and weight of the corpus cavemosum. Buried penis resulted in decreased smooth muscle content (P>0.05 in group A, and P0.05 in groups A and B, and P <0.05 in group C) compared with the normal and control groups. Ultrastructural abnormalities of corpus cavernosum were observed in the 6-month buried group. Moreover, there was decrease of NOS activity in groups B and C (P<0.05 in group B and P<0.01 in group C) when compared with the normal and control groups.Conclusion Buried penis affects the structure and function of corpus cavemosum in rats and the effect is positively correlated with the buried time, but there is no significant effect on the macroscopic development.

  1. SOI metal-oxide-semiconductor field-effect transistor photon detector based on single-hole counting.

    Science.gov (United States)

    Du, Wei; Inokawa, Hiroshi; Satoh, Hiroaki; Ono, Atsushi

    2011-08-01

    In this Letter, a scaled-down silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistor (MOSFET) is characterized as a photon detector, where photogenerated individual holes are trapped below the negatively biased gate and modulate stepwise the electron current flowing in the bottom channel induced by the positive substrate bias. The output waveforms exhibit clear separation of current levels corresponding to different numbers of trapped holes. Considering this capability of single-hole counting, a small dark count of less than 0.02 s(-1) at room temperature, and low operation voltage of 1 V, SOI MOSFET could be a unique photon-number-resolving detector if the small quantum efficiency were improved. PMID:21808317

  2. Fully Coupled FE Analyses of Buried Structures

    Directory of Open Access Journals (Sweden)

    James T. Baylot

    1994-01-01

    Full Text Available Current procedures for determining the response of buried structures to the effects of the detonation of buried high explosives recommend decoupling the free-field stress analysis from the structure response analysis. A fully coupled (explosive–soil structure finite element analysis procedure was developed so that the accuracies of current decoupling procedures could be evaluated. Comparisons of the results of analyses performed using this procedure with scale-model experiments indicate that this finite element procedure can be used to effectively evaluate the accuracies of the methods currently being used to decouple the free-field stress analysis from the structure response analysis.

  3. Buried Waste Integrated Demonstration stakeholder involvement model

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) is a program funded by the US Department of Energy (DOE) Office of Technology Development. BWID supports the applied research, development, demonstration, and evaluation of a suite of advanced technologies that together form a comprehensive remediation system for the effective and efficient remediation of buried waste. Stakeholder participation in the DOE Environmental Management decision-making process is critical to remediation efforts. Appropriate mechanisms for communication with the public, private sector, regulators, elected officials, and others are being aggressively pursued by BWID to permit informed participation. This document summarizes public outreach efforts during FY-93 and presents a strategy for expanded stakeholder involvement during FY-94

  4. Buried Waste Integrated Demonstration test objectives

    International Nuclear Information System (INIS)

    The mission of the Buried Waste Integrated Demonstration Program (BWID) is to support the development and demonstration of a suite of technologies that when integrated with commercially available baseline technologies form a comprehensive system for the effective and efficient remediation of buried waste throughout the US Department of Energy complex. To accomplish this mission of identifying technology solutions for remediation deficiencies, the Office of Technology Development initiated the BWID at the Idaho National Engineering Laboratory in fiscal year (FY) 1991. This document provides the test objectives against which the demonstrations will be tested during FY-93

  5. Magnetoresistance of a Spin Metal-Oxide-Semiconductor Field-Effect Transistor with Ferromagnetic MnAs Source and Drain Contacts

    Science.gov (United States)

    Nakane, Ryosho; Harada, Tomoyuki; Sugiura, Kuniaki; Tanaka, Masaaki

    2010-11-01

    Transport characteristics were investigated in a spin metal-oxide-semiconductor field-effect transistor (spin MOSFET) with ferromagnetic MnAs source and drain (S/D) contacts. A bottom-gate type spin MOSFET was fabricated by photolithography using an epitaxial MnAs film grown on a silicon-on-insulator (SOI) substrate. In-plane magnetoresistance showed a square like hysteretic behavior, when measurements were performed with constant source-drain and source-gate biases. From the comparison with the magnetization-related resistance change resulting from the MnAs contacts, a highly possible origin of the feature obtained for the spin MOSFET is the spin-valve effect originating from the spin-dependent transport in the Si channel.

  6. 7 CFR 1755.505 - Buried services.

    Science.gov (United States)

    2010-01-01

    ... 5 U.S.C. 552(a) and 1 CFR part 51. Copies are available from NFPA, 1 Batterymarch Park, P.O. Box... avoid damage from lawn mowers, animals, gardening operations, etc. (3) Buried service wire or cable... associated wiring 6 Metallic objects—pipes (gas, cold water, oil, sewer) and structures 4 2 Wires or...

  7. Analysis of buried pipelines at Kozloduy

    International Nuclear Information System (INIS)

    This paper describes the analysis of the buried pipelines at Kozloduy NPP. It involves the description of the studied pipelines, their properties, a detailed description of the methodology applied, and the evaluation of the soil strain field as well as the graphical representation of the results obtained

  8. Detection of Buried Objects : The MUD Project

    NARCIS (Netherlands)

    Quesson, B.A.J.; Vossen, R. van; Zampolli, M.; Beckers, A.L.D.

    2011-01-01

    The aim of the Mine Underwater Detection (MUD) project at TNO is to experimentally investigate the acoustic and magnetic detection of explosives underwater, buried in a soft sediment layer. This problem is relevant for the protection of harbors and littoral assets against terrorist attacks and for t

  9. How to bury your academic writing

    OpenAIRE

    Bishop, Dorothy

    2012-01-01

    Book chapters can allow freedom to think about your work in line with broader theoretical issues, but if you’re tempted to write a book chapter for an edited collection, it might be best to reconsider. Dorothy Bishop finds that researchers who write book chapters might as well bury the paper in a hole in their garden.

  10. Field-scale permeation testing of jet-grouted buried waste sites

    International Nuclear Information System (INIS)

    The Idaho National Engineering Laboratory (INEL) conducted field-scale hydraulic conductivity testing of simulated buried waste sites with improved confinement. The improved confinement was achieved by jet grouting the buried waste, thus creating solid monoliths. The hydraulic conductivity of the monoliths was determined using both the packer technique and the falling head method. The testing was performed on simulated buried waste sites utilizing a variety of encapsulating grouts, including high-sulfate-resistant Portland cement, TECT, (a proprietary iron oxide cement) and molten paraffin. By creating monoliths using in-situ jet grouting of encapsulating materials, the waste is simultaneously protected from subsidence and contained against further migration of contaminants. At the INEL alone there is 56,000 m3 of buried transuranic waste commingled with 170,000--224,000 m3 of soil in shallow land burial. One of the options for this buried waste is to improve the confinement and leave it in place for final disposal. Knowledge of the hydraulic conductivity for these monoliths is important for decision-makers. The packer tests involved coring the monolith, sealing off positions within the core with inflatable packers, applying pressurized water to the matrix behind the seal, and observing the water flow rate. The falling head tests were performed in full-scale 3-m-diameter, 3-m-high field-scale permeameters. In these permeameters, both water inflow and outflow were measured and equated to a hydraulic conductivity

  11. Single-Event Upset and Snapback in Silicon-on-Insulator Devices and Integrated Circuits

    Energy Technology Data Exchange (ETDEWEB)

    DODD,PAUL E.; SHANEYFELT,MARTY R.; WALSH,DAVID S.; SCHWANK,JAMES R.; HASH,GERALD L.; LOEMKER,RHONDA ANN; DRAPER,BRUCE L.; WINOKUR,PETER S.

    2000-08-15

    The characteristics Of ion-induced charge collection and single-event upset are studied in SOI transistors and circuits with various body tie structures. Impact ionization effects including single-event snapback are shown to be very important. Focused ion microbeam experiments are used to find single-event snapback drain voltage thresholds in n-channel SOI transistors as a function of device width. Three-Dimensional device simulations are used to determine single-event upset and snapback thresholds in SOI SRAMS, and to study design tradeoffs for various body-tie structures. A window of vulnerability to single-event snapback is shown to exist below the single-event upset threshold. The presence of single-event snapback in commercial SOI SRAMS is confirmed through broadbeam ion testing, and implications for hardness assurance testing of SOI integrated circuits are discussed.

  12. FABRICATION OF SILICON-ON-INSULATOR MEM RESONATORS WITH DEEP SUB-MICRON TRANSDUCTION GAPS

    OpenAIRE

    Badila, N.-D.; Hibert, C.; Mazza, M.; Ionescu, A.M.

    2006-01-01

    Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/5920) International audience The paper proposes and validates a low-cost technological process for realizing fully mono-crystalline MEM resonators with deep sub-micron transduction gaps on SOI substrates. The MEM resonators are designed to work as BLR (bulk lateral resonators) in which the resonance of a suspended mass is excited and detected by lateral electrodes. For MEM BLRs, nano-scaled gaps (

  13. Analysis of silicon-on-insulator slot waveguide ring resonators targeting high Q-factors.

    Science.gov (United States)

    Zhang, Weiwei; Serna, Samuel; Le Roux, Xavier; Alonso-Ramos, Carlos; Vivien, Laurent; Cassan, Eric

    2015-12-01

    Vertical slot waveguide micro-ring resonators in silicon photonics have already been demonstrated in previous works and applied to several schemes, including sensing and hybrid nonlinear optics. Their performances, first quantified by the reachable Q-factors, are still perceived to be restrained by larger intrinsic propagation losses than those suffered by simple Si wire waveguides. In this Letter, the optical loss mechanisms of slot waveguide micro-ring resonators are thoroughly investigated with a special focus on the coupler loss contribution that turns out to be the key obstacle to achieving high Q-factors. By engineering the coupler design, slotted ring resonators with a 50 μm radius are experienced with a loaded Q-factor up to 10 times improvement from Q=3,000 to Q=30,600. The intrinsic losses due to the light propagation in the bent slot ring itself are proved to be as low as 1.32±0.87  dB/cm at λ=1,550  nm. These investigations of slot ring resonators open high performance potentials for on-chip nonlinear optical processing or sensing in hybrid silicon photonics. PMID:26625052

  14. Low-loss strip-loaded slot waveguides in silicon-on-insulator.

    Science.gov (United States)

    Ding, Ran; Baehr-Jones, Tom; Kim, Woo-Joong; Xiong, Xugang; Bojko, Richard; Fedeli, Jean-Marc; Fournier, Maryse; Hochberg, Michael

    2010-11-22

    Electro-optic polymer-clad silicon slot waveguides have recently been used to build a new class of modulators, that exhibit very high bandwidths and extremely low drive voltages. A key step towards making these devices practical will be lowering optical insertion losses. We report on the first measurements of low-loss waveguides that are geometrically suitable for high bandwidth slot waveguide modulators: a strip-loaded slot waveguide. Waveguide loss for undoped waveguides of 6.5 ± 0.2 dB/cm was achieved with 40 nm thick strip-loading, with the full silicon thickness around 220 nm and a slot size of 200 nm, for wavelengths near 1550 nm. PMID:21164851

  15. Possibility of silicon-on-insulator (SOI) structure production using wet surface treatment and smart technique

    International Nuclear Information System (INIS)

    Full text: he proposed methods of silicon surface formation using heat treatment in wet environment (including chemical surface assembling by the molecular deposition method) and the smart technique allow to produce high-quality SOI-structures suitable for using in special ICs, semiconductor devices, micromechanical systems and sensors. We have carried out experiments of SOI-structures production using the smart technology (the radiation-induced gas-stimulated splitting) and surface treatment in wet environment. Preparation of wafers consisted of super-finished polishing and chemical treatment to obtain maximum clean and smooth surface. The hydrogen atom implantation was carried out in equipment with the ion current density on wafer surface of about 0.5 μA/cm2 and 5 μA/cm2. Ion energy was 40 and 150 keV. The samples have been obtained with the following implantation dozes: 3·1016; 4·1016, 5·1016; 7·1016, 1017 cm-2. Before joining, the samples were treated in 40 % solution of ammonia fluoride - 2 seconds, D.I. water - 10 minutes and 100 % nitric acid - 10 minutes, and after that - in D.I. water. Along with it special chemical treatment methods were investigated. The splitting was carried out by heat treatment in the diffusion furnace at 450-600 deg. C during 10-20 min in nitrogen or oxygen atmosphere. The device layer have completely splitted from device wafers with H+ implantation doze of 3·1016 cm-2. For H+ implantation dozes of 5·1016 cm-2, 7·1016 cm-2. 1017 cm-2 the device layer was splitted as small islands. This effect is explained by the absence of a continuous contact of wafers due to appearance of a micro relief of 40-450 nm height caused by growing blisters. This circumstance makes to search for special methods of joining and preliminary bonding of wafers before splitting (heat treatment at 120-300 deg. C), by selection of pressure of environment where the operation is carried out, by fine adjustment of H+ implantation doze. The structures obtained in described experiments had device layers of 0.3-0.8 microns thickness, roughness of outer surface of this layer was 20-30 nm. The following conclusions can be made basing on conducted experiments: 1) Formation of SOI-structures with thick device layers is feasible to carry out by the wafer bonding method and subsequent thinning of the device wafer; 2) The most prospective method of SOI-structures formation with thin device layers (less than 1 micron) is the method of splitting of the device layer from the structure obtained by the wafer bonding method; 3) To obtain SOI-structures with thicker device layers, the chemical-mechanical thinning and plasma etching methods are acceptable

  16. Efficient production of silicon-on-insulator films by co-implantation of He+ with H+

    International Nuclear Information System (INIS)

    We have investigated the process of thin film separation by gas ion implantation and wafer bonding, as well as the more basic phenomenon of blistering, on which the technique is based. We show that when H and He gas implants are combined they produce a synergistic effect which enables thin-film separation at a much lower total implantation dose than that required for either H or He alone. By varying the H and He implantation doses we have been able to isolate the physical and chemical contributions of the gases to the blistering processes. We find that the essential role of H is to interact chemically with the implantation damage and create H-stabilized platelet-like defects, or microvoids. The efficiency of H in this action is linked to its effective lowering of the silicon internal surface energy. The second key component of the process is physical; it consists of diffusion of gas into the microvoids and gas expansion during annealing, which drives growth and the eventual intersection of the microvoids to form two continuous separable surfaces. He is more efficient than H for this process since He does not become chemically trapped at broken bonds and thus segregates into microvoids more readily. In particular, we have demonstrated that a 1x1016 cm-2 He dose in combination with a 7.5x1015 cm-2 H dose are sufficient to shear and transfer a thin silicon film onto a handle wafer after bonding the two wafers together. copyright 1998 American Institute of Physics

  17. An ARROW-based silicon-on-insulator photonic crystal waveguides with reduced losses

    DEFF Research Database (Denmark)

    Lavrinenko, Andrei

    2006-01-01

    We employ an antiresonant reflecting layers arrangement for siliicon-on-insulator based photonic crystal waveguides with thin cores. 3D FDTD numerical modelling reveals the reduction of losses with a promising potential for competing with membrane-like waveguides.......We employ an antiresonant reflecting layers arrangement for siliicon-on-insulator based photonic crystal waveguides with thin cores. 3D FDTD numerical modelling reveals the reduction of losses with a promising potential for competing with membrane-like waveguides....

  18. Burying by rats in response to aversive and nonaversive stimuli

    OpenAIRE

    Poling, Alan; Cleary, James; Monaghan, Michael

    1981-01-01

    Previous investigations have shown that rats bury a variety of conditioned and unconditioned aversive stimuli. Such burying has been considered as a species-typical defensive reaction. In the present studies, rats buried spouts filled with Tabasco sauce, or condensed milk to which a taste aversion was conditioned, but did not bury water-filled spouts or spouts filled with a palatable novel food (apple juice) to which a taste aversion was not conditioned. However, in other experiments rats con...

  19. Revealing the Semiconductor-Catalyst Interface in Buried Platinum Black Silicon Photocathodes

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Jeffery A.; Anderson, Nicholas C.; Neale, Nathan R.

    2016-06-07

    Nanoporous 'black' silicon semiconductors interfaced with buried platinum nanoparticle catalysts have exhibited stable activity for photoelectrochemical hydrogen evolution even after months of exposure to ambient conditions. The mechanism behind this stability has not been explained in detail, but is thought to involve a Pt/Si interface free from SiOx layer that would adversely affect interfacial charge transfer kinetics. In this paper, we resolve the chemical composition and structure of buried Pt/Si interfaces in black silicon photocathodes from a micron to sub-nanometer level using aberration corrected analytical scanning transmission electron microscopy. Through a controlled electrodeposition of copper on samples aged for one month in ambient conditions, we demonstrate that the main active catalytic sites are the buried Pt nanoparticles located below the 400-800 nm thick nanoporous SiOx layer. Though hydrogen production performance degrades over 100 h under photoelectrochemical operating conditions, this burying strategy preserves an atomically clean catalyst/Si interface free of oxide or other phases under air exposure and provides an example of a potential method for stabilizing silicon photoelectrodes from oxidative degradation in photoelectrochemical applications.

  20. Transformation of lignin in surface and buried soils of mountainous landscapes

    Science.gov (United States)

    Kovaleva, N. O.; Kovalev, I. V.

    2009-11-01

    The content and composition of the lignin phenols in plants and soils of vertical natural zones were studied in the Northern Caucasus region and Northwestern Tien Shan. Three types of lignin transformation were revealed: steppe, forest, and meadow ones. It was shown that the degree of oxidation of the biopolymer during the transformation of organic matter increased when going from the living plant tissues to humic acids in surface and buried soils. The portion of lignin fragments remained unchanged during the biopolymer transformation in the following series: plant tissues-falloff-litter-soil-humic acids-buried humic acids. It was also shown that the biochemical composition of the plants had a decisive effect on the structure of the humic acids in the soils. The quantitative analysis of the lignin phenols and the 13C NMR spectroscopy proved that the lignin in higher plants was involved in the formation of specific compounds of soil humus, including aliphatic and aromatic molecular fragments. The first analysis of the lignin content and composition in buried soils of different ages was performed, and an increase in the degree of oxidation of the lignin structures was revealed in the soil chronoseries. It was proposed to use the proportions of lignin phenols in surface and buried soils as diagnostic criteria of the vegetation types in different epochs.

  1. Rear surface passivation in buried contact solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Y.H.; Dai, X.M.; Zhao, J.H.; Wang, A.H.; Wenham, S.R.; Honsberg, C.B. [Univ. of New South Wales, Sydney, New South Wales (Australia). Photovoltaic Special Research Centre

    1997-12-31

    A range of rear surface structures have been developed and studied for the purpose of improving the performance of buried contact solar cells (BCSC). In particular, improved results are reported for the double grooved BCSC with oxidized p-type rear surface, with V{sub oc} of 685 mV having been demonstrated. The importance of including an alneal treatment is clearly evident with open circuit voltages typically degrading 60 mV without its inclusion. Devices with the same structure but with a rear floating junction are also evaluated within the study and again the dependence on an alneal is evident for cells with low surface phosphorus concentration. In the highest voltage devices, the rear boron diffused grooves contribute almost 30% of the total device dark saturation current, with test devices achieving V{sub oc} as high as 694 mV for a BCSC with the rear grooves replaced by photolithographically defined boron diffused contact regions.

  2. Resonant soft x-ray scattering studies of buried interfaces

    International Nuclear Information System (INIS)

    Resonant soft x-ray scattering (RSXS) is a unique experimental tool to access the electronic properties of buried interfaces in heterostructures that contain transition metal oxides. In this contribution, studies of SrTiO3/LaAlO3, SrTiO3/(La,Ca)MnO3 and NdGaO3/(La,Ca)MnO3 interfaces are presented. Specifically, RSXS was employed to examine the electronic reconstruction of Ti 3d and O 2p valence states at the interfaces of SrTiO3/LaAlO3 superlattices. Similarly, we used resonant soft x-ray reflectivity to investigate the electronic structure at the interfaces of SrTiO3/(La,Ca)MnO3 and NdGaO3/(La,Ca)MnO3 thin film systems.

  3. Buried Waste Integrated Demonstration Strategy Plan

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a suite of advanced technologies that form a comprehensive remediation system for the effective and efficient remediation of buried waste. These efforts are identified and coordinated in support of the US Department of Energy (DOE), Environmental Restoration and Waste Management (ERWM) needs and objectives. The present focus of BWID is to support retrieval and ex situ treatment configuration options. Future activities will explore and support containment and stabilization efforts in addition to the retrieval/ex situ treatment options. Long and short term strategies of the BWID are provided. Processes for identifying technological needs, screening candidate technologies for BWID applicability, researching technical issues, field demonstrating technologies, evaluating demonstration results to determine each technology's threshold of capability, and commercializing successfully demonstrated technologies for implementation for environmental restoration also are presented in this report

  4. Seismic induced earth pressures in buried vaults

    International Nuclear Information System (INIS)

    The magnitude and distribution of earth pressures acting on buried structures and induced by a seismic event are considered in this paper. A soil-structure-interaction analysis is performed for typical Department of Energy high level waste storage tanks using a lumped parameter model. The resulting soil pressure distributions are determined and compared with the static soil pressure to assess the design significance of the seismic induced soil pressures. It is found that seismic pressures do not control design unless the peak ground acceleration exceeds about 0.3 G. The effect of soil non linearities (resulting from local soil failure) are also found to have little effect on the predictions of the seismic response of the buried structure. The seismic induced pressures are found to be very similar to those predicted using the elastic model in ASCE 4-86

  5. DOE complex buried waste characterization assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kaae, P.S.; Holter, G.M.; Garrett, S.M.K.

    1993-01-01

    The work described in this report was conducted by Pacific Northwest Laboratory to provide information to the Buried Waste Integrated Demonstration (BWID) program. The information in this report is intended to provide a complex-wide planning base for th.e BWID to ensure that BWID activities are appropriately focused to address the range of remediation problems existing across the US Department of Energy (DOE) complex. This report contains information characterizing the 2.1 million m[sup 3] of buried and stored wastes and their associated sites at six major DOE facilities. Approximately 85% of this waste is low-level waste, with about 12% TRU or TRU mixed waste; the remaining 3% is low-level mixed waste. In addition, the report describes soil contamination sites across the complex. Some of the details that would be useful in further characterizing the buried wastes and contaminated soil sites across the DOE complex are either unavailable or difficult to locate. Several options for accessing this information and/or improving the information that is available are identified in the report. This document is a companion to Technology Needs for Remediation: Hanford and Other DOE Sites, PNL-8328 (Stapp 1993).

  6. Multiple instance learning for buried hazard detection

    Science.gov (United States)

    Rice, Joseph; Pinar, Anthony; Havens, Timothy C.; Webb, Adam; Schulz, Timothy J.

    2016-05-01

    Buried explosives hazards are one of the many deadly threats facing our Soldiers, thus the U.S. Army is interested in the detection and neutralization of these hazards. One method of buried target detection uses forward-looking ground-penetrating radar (FLGPR), and it has grown in popularity due to its ability to detect buried targets at a standoff distance. FLGPR approaches often use machine learning techniques to improve the accuracy of detection. We investigate an approach to explosive hazard detection that exploits multi-instance features to discriminate between hazardous and non-hazardous returns in FLGPR data. One challenge this problem presents is a high number of clutter and non-target objects relative to the number of targets present. Our approach learns a bag of words model of the multi-instance signatures of potential targets and confuser objects in order to classify alarms as either targets or false alarms. We demonstrate our method on test data collected at a U.S. Army test site.

  7. Simulation of suppression of floating-body effect in partially depleted SOI MOSFET using a Si1-x Ge x dual source structure

    International Nuclear Information System (INIS)

    The effect of the Si1-x Ge x source with an underlying p+ region on the suppression of the floating body effects in a partially depleted silicon-on-insulator (SOI) metal oxide silicon field effect transistor (MOSFET) is numerically investigated. Compared to a conventional SOI MOSFET, the kink effect and anomalous sub-threshold slope are reduced and the breakdown voltage is substantially increased. The detailed suppression mechanism is also studied. Our results suggest that the narrow bandgap Si1-x Ge x source and buried p+ region are favorable to the dispersion of holes generated by impact ionization

  8. Field application of innovative grouting agents for in situ stabilization of buried waste sites

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, G.G.; Farnsworth, R.K. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1997-12-31

    This paper presents field applications for two innovative grouting agents that were used to in situ stabilize buried waste sites, via jet grouting. The two grouting agents include paraffin and a proprietary iron oxide based cement grout called TECT. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory (INEL). The field demonstrations were performed at the INEL in an area referred to as the Cold Test Pit, which is adjacent to the INEL Radioactive Waste Management Complex (RWMC). At the RWMC, 56,000 m{sup 3} of transuranic (TRU) waste is co-mingled with over 170,000 m{sup 3} of soil in shallow land burial. Improving the confinement of this waste is one of the options for final disposition of this waste. Using jet-grouting technology to inject these materials into the pore spaces of buried waste sites results in the creation of buried monolithic waste forms that simultaneously protect the waste from subsidence, while eliminating the migratory potential of hazardous and radioactive contaminants in the waste.

  9. Buried Alive: Microbes from Ancient Halite.

    Science.gov (United States)

    Jaakkola, Salla T; Ravantti, Janne J; Oksanen, Hanna M; Bamford, Dennis H

    2016-02-01

    Halite is one of the most extreme environments to support life. From the drought of the Atacama Desert to salt deposits up to Permian in age and 2000 meters in burial depth, live microbes have been found. Because halite is geologically stable and impermeable to ground water, the microbes allegedly have a syndepositional origin, making them the oldest organisms known to live on Earth. Recently, our understanding of the microbial diversity inside halite has broadened, and the first genome sequences of ancient halite-buried microbes are now available. The secrets behind prolonged survival in salt are also starting to be revealed. PMID:26796472

  10. Virtual environmental applications for buried waste characterization technology evaluation report

    International Nuclear Information System (INIS)

    The project, Virtual Environment Applications for Buried Waste Characterization, was initiated in the Buried Waste Integrated Demonstration Program in fiscal year 1994. This project is a research and development effort that supports the remediation of buried waste by identifying and examining the issues, needs, and feasibility of creating virtual environments using available characterization and other data. This document describes the progress and results from this project during the past year

  11. Virtual environmental applications for buried waste characterization technology evaluation report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The project, Virtual Environment Applications for Buried Waste Characterization, was initiated in the Buried Waste Integrated Demonstration Program in fiscal year 1994. This project is a research and development effort that supports the remediation of buried waste by identifying and examining the issues, needs, and feasibility of creating virtual environments using available characterization and other data. This document describes the progress and results from this project during the past year.

  12. In situ grouting of buried transuranic waste

    International Nuclear Information System (INIS)

    This task is a demonstration and evaluation of the in situ hydrologic stabilization of buried transuranic waste at a humid site via grout injection. Two small trenches, containing buried transuranic waste, were filled with 34,000 liters of polyacrylamide grout. Initial field results have indicated that voids within the trenches were totally filled by the grout and that the intratrench hydraulic conductivity was reduced to below field-measurable values. The grout was also completely contained within the two trenches as no grout constituents were observed in the 12 perimeter ground water monitoring wells. Polyacrylamide grout was selected for field demonstration over polyacrylate grout because of its superior performance in laboratory degradation studies. Also supporting the selection of polyacrylamide was the difficulty of controlling the set time of the acrylate polymerization process in the presence of potassium ferricyanide. Based on preliminary degradation monitoring, polyacrylamide was estimated to have a microbiological half-life of 115 years in the test soil. However, this calculated value is likely to be conservatively low because microbial degradation of the grout set accelerator or residual monomer may be contributing most to the measured microbial respiration. Addition work, using 14C-labeled acrylate and acrylamide grouts, is being carried out to more accurately estimate the grouts' microbiological half-life

  13. The growth of ultra thin Praseodymia oxide films on boron-passivated Si(111) surfaces

    International Nuclear Information System (INIS)

    Silicon on insulator (SOI) CMOS technology already have an enormous commercial impact with Si dioxide as insulating material. Alternative insulating materials are in the focus of investigation to integrate semiconductors for system on chip (SOC) solutions that cannot be built on Si alone. Due to its good insulations characteristics and a high dielectric constant, praseodymium oxide is an interesting candidate for such applications. To prevent the formation of silicate at the substrate-oxide interface it is essential to use passivated silicon substrates. In this work the influence of boron-passivation is investigated. Prior to praseodymium oxide evaporation by molecular beam epitaxy the Si substrate surface was passivated by boron via evaporation of boric acid and subsequent annealing of the substrate to 900 C. In situ Spot Profile Analysis Low Energy Electron Diffraction (SPA-LEED) and Auger Electron Spectroscopy (AES) were used to characterize the surface structure and morphology. Additional Ex-situ X-Ray Reflectivity (XRR) and X-Ray Diffraction (XRD) analyses were performed. The results show that at a substrate temperature of 500 C a single crystalline oxide film is formed.

  14. Ion beam synthesis of buried oxide layers in silicon carbide

    International Nuclear Information System (INIS)

    A field emission gun scanning transmission electron microscope equipped with an energy-dispersive X-ray spectrometer (EDX) and an electron energy loss spectrometer (EELS) has been used to characterize the microstructures, elemental distributions, and chemical bonding states of oxygen ion implanted silicon carbide (SiC). 6H-SiC substrates with the (0 0 0 1) orientation were implanted with 180 keV oxygen ions at 650 deg. C to fluences of 0.7x1018 and 1.4x1018 cm-2. A continuous amorphous layer is formed in the as-implanted state under these irradiation conditions. The amorphous layer is uniform in the low-dose sample, while it consists of three layers in the high-dose one. EDX maps of elemental distributions suggest that the layered structure in the latter sample originates from compositional fluctuations of silicon, carbon and oxygen. EELS measurements suggest that the amorphous regions in the high-dose sample consist of well-defined SiO2 layer which is accompanied by sp2-bonded carbon

  15. Numerical study of self-heating effects of small-size MOSFETs fabricated on silicon-on-aluminum nitride substrate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Compared with bulk-silicon technology, silicon-on-insulator (SOI) technology possesses many advantages but it is inevitable that the buried silicon dioxide layer also thermally insulates the metal-oxide-silicon field-effect transistors (MOSFETs) from the bulk due to the low thermal conductivity. One of the alternative insulator to replace the buried oxide layer is aluminum nitride (MN), which has a thermal conductivity that is about 200 times small-size MOSFETs fabricated on silicon-on-aluminum nitride (SOAN) substrate, a two-dimensional numerical analysis is performed by using a device simulator called MEDICI run on a Solaris workstation to simulate the electrical characteristics and temperature distribution by comparing with those of bulk and standard SOI MOSFETs. Our study suggests that AlN is a suitable alternative to silicon dioxide as a buried dielectric in SOI and expands the applications of SOI to high temperature conditions.

  16. Radiation and Electromagnetic Induction Data Fusion for Detection of Buried Radioactive Metal Waste - 12282

    International Nuclear Information System (INIS)

    At the United States Army's test sites, fired penetrators made of Depleted Uranium (DU) have been buried under ground and become hazardous waste. Previously, we developed techniques for detecting buried radioactive targets. We also developed approaches for locating buried paramagnetic metal objects by utilizing the electromagnetic induction (EMI) sensor data. In this paper, we apply data fusion techniques to combine results from both the radiation detection and the EMI detection, so that we can further distinguish among DU penetrators, DU oxide, and non- DU metal debris. We develop a two-step fusion approach for the task, and test it with survey data collected on simulation targets. In this work, we explored radiation and EMI data fusion for detecting DU, oxides, and non-DU metals. We developed a two-step fusion approach based on majority voting and a set of decision rules. With this approach, we fuse results from radiation detection based on the RX algorithm and EMI detection based on a 3-step analysis. Our fusion approach has been tested successfully with data collected on simulation targets. In the future, we will need to further verify the effectiveness of this fusion approach with field data. (authors)

  17. Buried waste integrated demonstration technology integration process

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, J.S.; Ferguson, J.E.

    1992-04-01

    A Technology integration Process was developed for the Idaho National Energy Laboratories (INEL) Buried Waste Integrated Demonstration (BWID) Program to facilitate the transfer of technology and knowledge from industry, universities, and other Federal agencies into the BWID; to successfully transfer demonstrated technology and knowledge from the BWID to industry, universities, and other Federal agencies; and to share demonstrated technologies and knowledge between Integrated Demonstrations and other Department of Energy (DOE) spread throughout the DOE Complex. This document also details specific methods and tools for integrating and transferring technologies into or out of the BWID program. The document provides background on the BWID program and technology development needs, demonstrates the direction of technology transfer, illustrates current processes for this transfer, and lists points of contact for prospective participants in the BWID technology transfer efforts. The Technology Integration Process was prepared to ensure compliance with the requirements of DOE's Office of Technology Development (OTD).

  18. Buried waste integrated demonstration technology integration process

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, J.S.; Ferguson, J.E.

    1992-04-01

    A Technology integration Process was developed for the Idaho National Energy Laboratories (INEL) Buried Waste Integrated Demonstration (BWID) Program to facilitate the transfer of technology and knowledge from industry, universities, and other Federal agencies into the BWID; to successfully transfer demonstrated technology and knowledge from the BWID to industry, universities, and other Federal agencies; and to share demonstrated technologies and knowledge between Integrated Demonstrations and other Department of Energy (DOE) spread throughout the DOE Complex. This document also details specific methods and tools for integrating and transferring technologies into or out of the BWID program. The document provides background on the BWID program and technology development needs, demonstrates the direction of technology transfer, illustrates current processes for this transfer, and lists points of contact for prospective participants in the BWID technology transfer efforts. The Technology Integration Process was prepared to ensure compliance with the requirements of DOE`s Office of Technology Development (OTD).

  19. Buried waste integrated demonstration technology integration process

    International Nuclear Information System (INIS)

    A Technology integration Process was developed for the Idaho National Energy Laboratories (INEL) Buried Waste Integrated Demonstration (BWID) Program to facilitate the transfer of technology and knowledge from industry, universities, and other Federal agencies into the BWID; to successfully transfer demonstrated technology and knowledge from the BWID to industry, universities, and other Federal agencies; and to share demonstrated technologies and knowledge between Integrated Demonstrations and other Department of Energy (DOE) spread throughout the DOE Complex. This document also details specific methods and tools for integrating and transferring technologies into or out of the BWID program. The document provides background on the BWID program and technology development needs, demonstrates the direction of technology transfer, illustrates current processes for this transfer, and lists points of contact for prospective participants in the BWID technology transfer efforts. The Technology Integration Process was prepared to ensure compliance with the requirements of DOE's Office of Technology Development (OTD)

  20. Landslide Buries Valley of the Geysers

    Science.gov (United States)

    2007-01-01

    Geysers are a rare natural phenomena found only in a few places, such as New Zealand, Iceland, the United States (Yellowstone National Park), and on Russia's far eastern Kamchatka Peninsula. On June 3, 2007, one of these rare geyser fields was severely damaged when a landslide rolled through Russia's Valley of the Geysers. The landslide--a mix of mud, melting snow, trees, and boulders--tore a scar on the land and buried a number of geysers, thermal pools, and waterfalls in the valley. It also blocked the Geyser River, causing a new thermal lake to pool upstream. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite captured this infrared-enhanced image on June 11, 2007, a week after the slide. The image shows the valley, the landslide, and the new thermal lake. Even in mid-June, just days from the start of summer, the landscape is generally covered in snow, though the geologically heated valley is relatively snow free. The tree-covered hills are red (the color of vegetation in this false-color treatment), providing a strong contrast to the aquamarine water and the gray-brown slide. According to the Russian News and Information Agency (RIA) [English language], the slide left a path roughly a kilometer and a half (one mile) long and 200 meters (600 feet) wide. Within hours of the landslide, the water in the new lake inundated a number of additional geysers. The geysers directly buried under the landslide now lie under as much as 60 meters (180 feet) of material, according to RIA reports. It is unlikely that the geysers will be able to force a new opening through this thick layer, adds RIA. Among those directly buried is Pervenets (Firstborn), the first geyser found in the valley, in 1941. Other geysers, such as the Bolshoi (Greater) and Maly (Lesser) Geysers, were silenced when buried by water building up behind the new natural dam. According to Vladimir and Andrei Leonov of the Russian Federation Institute of

  1. detection of buried objects using acoustic waves

    International Nuclear Information System (INIS)

    Many obstacles are faced in removing the buried landmines such as the loss or absence of maps or information about these mines and the high financial costs needed to remove these mines. So that many techniques were designed and developed for demining (detecting and clearing) these buried mines. Each technique has some strengths and drawbacks. This thesis presents a survey on the landmine detection techniques, the strengths and limitations of these techniques are highlighted and compared to show the ideal conditions and the challenges facing each technique. Furthermore, a comparison between these techniques from the points of view of cost, complexity, speed, safety, false alarms in detection and the effect of the environmental conditions is presented. one of the reliable and powerful landmine detection techniques is the Laser Doppler Vibrometer (LDV)-based Acoustic to Seismic (A/S) landmine detection system. The interpretation of the LDV-based A/S data is performed off-line manually, depending heavily on the skills, experience, alertness and consistency of a trained operator. This requires a significantly long time. Results typically suffer from inconsistency and errors, particularly when dealing with large volumes of data. This thesis proposes several image processing techniques to automate the process of landmine detection from the data scanned by the LDV-based A/S system. The obtained results are so far promising in terms of accuracy, consistency, reliability and processing speed. The previously proposed techniques for landmine detection give high false alarm rates. This thesis proposes some techniques to improve the performance of the automatic object detection techniques. These techniques are based on segmentation, masking, morphology image processing and the wavelet transform. These techniques have achieved a high detection rate.

  2. Including Arbitrary Antenna Patterns in Microwave Imaging of Buried Objects

    DEFF Research Database (Denmark)

    Meincke, Peter; Kim, Oleksiy S.; Lenler-Eriksen, Hans-Rudolph

    A linear inversion scheme for microwave imaging of buried objects is presented in which arbitrary antennas are accounted for through their plane-wave transmitting and receiving spectra......A linear inversion scheme for microwave imaging of buried objects is presented in which arbitrary antennas are accounted for through their plane-wave transmitting and receiving spectra...

  3. Buried bumper syndrome: a rare complication of percutaneous endoscopic gastrostomy.

    Science.gov (United States)

    Kurek, Krzysztof; Baniukiewicz, Andrzej; Świdnicka-Siergiejko, Agnieszka

    2015-09-01

    Feeding via percutaneous endoscopic gastrostomy (PEG) is the preferred form of alimentation when oral feeding is impossible. Although it is a relatively safe method, some complications may occur. One uncommon PEG complication is buried bumper syndrome. In this paper we report a case of buried bumper syndrome, successfully managed with PEG tube repositioning. PMID:26649105

  4. Heterojunction fully depleted SOI-TFET with oxide/source overlap

    Science.gov (United States)

    Chander, Sweta; Bhowmick, B.; Baishya, S.

    2015-10-01

    In this work, a hetero-junction fully depleted (FD) Silicon-on-Insulator (SOI) Tunnel Field Effect Transistor (TFET) nanostructure with oxide overlap on the Germanium-source region is proposed. Investigations using Synopsys Technology Computer Aided Design (TCAD) simulation tools reveal that the simple oxide overlap on the Germanium-source region increases the tunneling area as well as the tunneling current without degrading the band-to-band tunneling (BTBT) and improves the device performance. More importantly, the improvement is independent of gate overlap. Simulation study shows improvement in ON current, subthreshold swing (SS), OFF current, ION/IOFF ration, threshold voltage and transconductance. The proposed device with hafnium oxide (HfO2)/Aluminium Nitride (AlN) stack dielectric material offers an average subthreshold swing of 22 mV/decade and high ION/IOFF ratio (∼1010) at VDS = 0.4 V. Compared to conventional TFET, the Miller capacitance of the device shows the enhanced performance. The impact of the drain voltage variation on different parameters such as threshold voltage, subthreshold swing, transconductance, and ION/IOFF ration are also found to be satisfactory. From fabrication point of view also it is easy to utilize the existing CMOS process flows to fabricate the proposed device.

  5. Integrated test schedule for buried waste integrated demonstration

    International Nuclear Information System (INIS)

    The Integrated Test Schedule incorporates the various schedules the Buried Waste Integrated Demonstration (BWID) supports into one document. This document contains the Federal Facilities Agreement and Consent Order schedules for the Idaho National Engineering Laboratory, Hanford Reservation, Oak Ridge Reservation, and Fernald Environmental Materials Center. Included in the Integrated Test Schedule is the Buried Waste Integrated Demonstration ''windows of opportunity'' schedule. The ''windows of opportunity'' schedule shows periods of time in which Buried Waste Integrated Demonstration Program-sponsored technology demonstrations could support key decisions in the Federal Facilities Agreement and Consent Order. Schedules for the Buried Waste Integrated Demonstration-sponsored technology task plans are categorized by technology area and divided by current fiscal year and out-year. Total estimated costs for Buried Waste Integrated Demonstration-sponsored Technology Task Plans for FY-92 through FY-97 are $74.756M

  6. DOE complex buried waste characterization assessment. Buried Waste Integrated Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    Kaae, P.S.; Holter, G.M.; Garrett, S.M.K.

    1993-01-01

    The work described in this report was conducted by Pacific Northwest Laboratory to provide information to the Buried Waste Integrated Demonstration (BWID) program. The information in this report is intended to provide a complex-wide planning base for th.e BWID to ensure that BWID activities are appropriately focused to address the range of remediation problems existing across the US Department of Energy (DOE) complex. This report contains information characterizing the 2.1 million m{sup 3} of buried and stored wastes and their associated sites at six major DOE facilities. Approximately 85% of this waste is low-level waste, with about 12% TRU or TRU mixed waste; the remaining 3% is low-level mixed waste. In addition, the report describes soil contamination sites across the complex. Some of the details that would be useful in further characterizing the buried wastes and contaminated soil sites across the DOE complex are either unavailable or difficult to locate. Several options for accessing this information and/or improving the information that is available are identified in the report. This document is a companion to Technology Needs for Remediation: Hanford and Other DOE Sites, PNL-8328 (Stapp 1993).

  7. Strong and Tough Layered Nanocomposites with Buried Interfaces.

    Science.gov (United States)

    Chen, Ke; Tang, Xuke; Yue, Yonghai; Zhao, Hewei; Guo, Lin

    2016-04-26

    In nacre, the excellent mechanical properties of materials are highly dependent on their intricate hierarchical structures. However, strengthening and toughening effects induced by the buried inorganic-organic interfaces actually originate from various minerals/ions with small amounts, and have not drawn enough attention yet. Herein, we present a typical class of artificial nacres, fabricated by graphene oxide (GO) nanosheets, carboxymethylcellulose (CMC) polymer, and multivalent cationic (M(n+)) ions, in which the M(n+) ions cross-linking with plenty of oxygen-containing groups serve as the reinforcing "evocator", working together with other cooperative interactions (e.g., hydrogen (H)-bonding) to strengthen the GO/CMC interfaces. When compared with the pristine GO/CMC paper, the cross-linking strategies dramatically reinforce the mechanical properties of our artificial nacres. This special reinforcing effect opens a promising route to strengthen and toughen materials to be applied in aerospace, tissue engineering, and wearable electronic devices, which also has implication for better understanding of the role of these minerals/ions in natural materials for the mechanical improvement. PMID:27070962

  8. Processing, microstructure, and electric properties of buried resistors in low-temperature co-fired ceramics

    International Nuclear Information System (INIS)

    The electrical properties of ruthenium oxide based devitrifiable resistors embedded within low-temperature co-fired ceramics were investigated from -100oC to 100oC. Special attention was given to the processing conditions and their effects on resistance and temperature coefficient of resistance (TCR). Results indicate that within this temperature range the conductance for these buried resistors is limited by tunneling of charge carriers through the thin glass layer between ruthenium oxide particles. A modified version of the tunneling barrier model is proposed to account for the microstructure ripening observed during thermal processing. The model parameters determined from curve fitting show that charging energy (i.e., the energy required for a charge carrier to tunnel through the glass barrier) is strongly dependent on particle size and particle--particle separation between ruthenium oxide grains. Initial coarsening of ruthenium oxide grains was found to reduce the charging energy and lower the resistance. However, when extended ripening occurs, the increase in particle--particle separation increases the charging energy, reduces the tunneling probability and gives rise to a higher resistance. The tradeoff between these two effects results in an optimum microstructure with a minimum resistance and TCR. Furthermore, the TCR of these buried resistors has been shown to be governed by the magnitude of the charging energy. Model parameters determined by our analysis appear to provide quantitative physical interpretations to the microstructural changes in the resistor, which in turn, are controlled by the processing conditions

  9. Compact Buried Ducts in a Hot-Humid Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, Dave [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-07

    "9A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval. The primary research question with buried ducts is potential condensation at the outer jacket of the duct insulation in humid climates during the cooling season. Current best practices for buried ducts rely on encapsulating the insulated ducts with closed-cell spray polyurethane foam insulation to control condensation and improve air sealing. The encapsulated buried duct concept has been analyzed and shown to be effective in hot-humid climates. The purpose of this project is to develop an alternative buried duct system that performs effectively as ducts in conditioned space - durable, energy efficient, and cost-effective - in a hot-humid climate (IECC warm-humid climate zone 3A) with three goals that distinguish this project: 1) Evaluation of design criteria for buried ducts that use common materials and do not rely on encapsulation using spray foam or disrupt traditional work sequences; 2) Establishing design criteria for compact ducts and incorporate those with the buried duct criteria to further reduce energy losses and control installed costs; 3) Developing HVAC design guidance for performing accurate heating and cooling load calculations for compact buried ducts.

  10. Xenon Isotope Releases from Buried Transuranic Waste

    Science.gov (United States)

    Dresel, P. E.; Waichler, S. R.; Kennedy, B. M.; Hayes, J. C.; McIntyre, J. I.; Giles, J. R.; Sondrup, A. J.

    2004-12-01

    Xenon is an inert rare gas produced as a fission product in nuclear reactors and through spontaneous fission of some transuranic isotopes. Thus, xenon will be released from buried transuranic waste. Two complementary methods are used to measure xenon isotopes: radiometric analysis for short-lived radioxenon isotopes and mass spectrometry for detection of stable xenon isotopes. Initial measurements near disposal facilities at the U.S. Department of Energy's Hanford Site show radioxenon and stable xenon isotopic signatures that are indicative of transuranic waste. Radioxenon analysis has greater sensitivity due to the lower background concentrations and indicates spontaneous fission due to the short half life of the isotopes. Stable isotope ratios may be used to distinguish irradiated fuel sources from pure spontaneous fission sources and are not as dependent on rapid release from the waste form. The release rate is dependent on the type of waste and container integrity and is the greatest unknown in application of this technique. Numerical multi-phase transport modeling of burial grounds at the Idaho National Engineering and Environmental Laboratory indicates that, under generalized conditions, the radioxenon isotopes will diffuse away from the waste and be found in the soil cap and adjacent to the burial ground at levels many orders of magnitude above the detection limit.

  11. Seismic investigation of buried concrete pipes

    International Nuclear Information System (INIS)

    One of the most important natural hazards, that is effective on human life, is earthquake. Iran is one of the seismic zones in the world, so all of facilities and structures should have resistance capability against earthquake. Because of more necessity after earthquake, lifeline have special importance. In this work, seismic investigation of buried concrete pipes, as a part of lifeline, is done. These pipes have diameter more than 1.5 m and joints between pipe segments, have special shapes with special rubber gasket. Pipe segments are modelled as 3-D beams and joint between them are explained by axial and rotational springs. Pipe-soil interaction is expressed as springs and dash-pot in three directions. A nonlinear dynamic analysis of a six segments model is done and the effect of different parameters on pipe-soil interaction, pipe strain and pipe curvature, relative joint displacement and relative joint rotation is studied. The concluded results show that soil incontinuously along the pipeline, incident wave frequency, joint stiffness and soil stiffness are effective parameters in seismic response of pipes

  12. Magnetic dichroism in angle-resolved hard x-ray photoemission from buried layers

    Science.gov (United States)

    Kozina, Xeniya; Fecher, Gerhard H.; Stryganyuk, Gregory; Ouardi, Siham; Balke, Benjamin; Felser, Claudia; Schönhense, Gerd; Ikenaga, Eiji; Sugiyama, Takeharu; Kawamura, Naomi; Suzuki, Motohiro; Taira, Tomoyuki; Uemura, Tetsuya; Yamamoto, Masafumi; Sukegawa, Hiroaki; Wang, Wenhong; Inomata, Koichiro; Kobayashi, Keisuke

    2011-08-01

    This work reports the measurement of magnetic dichroism in angular-resolved photoemission from in-plane magnetized buried thin films. The high bulk sensitivity of hard x-ray photoelectron spectroscopy (HAXPES) in combination with circularly polarized radiation enables the investigation of the magnetic properties of buried layers. HAXPES experiments with an excitation energy of 8 keV were performed on exchange-biased magnetic layers covered by thin oxide films. Two types of structures were investigated with the IrMn exchange-biasing layer either above or below the ferromagnetic layer: one with a CoFe layer on top and another with a Co2FeAl layer buried beneath the IrMn layer. A pronounced magnetic dichroism is found in the Co and Fe 2p states of both materials. The localization of the magnetic moments at the Fe site conditioning the peculiar characteristics of the Co2FeAl Heusler compound, predicted to be a half-metallic ferromagnet, is revealed from the magnetic dichroism detected in the Fe 2p states.

  13. Characterization plan for TNX Burying Ground, Savannah River Plant

    International Nuclear Information System (INIS)

    The TNX Burying Ground, which is located within the TNX security fenceline, was originally built in 1953 for the disposal of waste and debris from an experimental evaporator explosion. The material buried contained approximately 590 kg of uranyl nitrate, with unspecified amounts of tin, conduit, timbers, and other debris. Partial removals were performed in the early 1980s when the waste was encountered during the construction of buildings and process structures at TNX. This Characterization Plan has been prepared to fulfill requirements outlined in the ''Scope of Work for Technical Assistance on Characterization of the TNX Burying Ground.'' This plan provides recommendations for collection of technical data to characterize the Savannah River Plant (SRP) TNX Burying Ground by identifying the numbers, types, depths, and locations of samples, the analyses to be performed, and the methodologies for collection

  14. Response of buried pipes to missile impact

    International Nuclear Information System (INIS)

    This paper presents the methodology and results of the analyses carried out to determine an effective layout and the dynamic response of safety related cooling water pipes, buried in backfill, for the Alto Lazio Nuclear Power Plant in Italy, subjected to missile impact loading at the backfill surface. The pipes are composed of a steel plate encased in two layers of high-quality reinforced concrete. The methodology comprises three steps. The first step is the definition of the 'free-field' dynamic response of the backfill soil, not considering the presence of the pipes, through a dynamic finite element direct integration analysis utilizing an axisymmetric model. The second step is the pipe-soil interaction analysis, which is conducted by utilizing the soil displacement and stress time-histories obtained in the previous steps. Soil stress time-histories, combined with the geostatic and other operational stresses (such as those due to temperature and pressure), are used to obtain the actions in the pipe walls due to ring type deformation. For the third step, the analysis of the beam type response, a lumped parameter model is developed which accounts for the soil stiffness, the pipe characteristics and the position of the pipe with respect to the impact area. In addition, the effect of the presence of large concrete structures, such as tunnels, between the ground surface and the pipe is evaluated. The results of the structural analyses lead to defining the required steel thickness and also allow the choice of appropriate embedment depth and layout of redundant lines. The final results of the analysis is not only the strength verification of the pipe section, but also the definition of an effective layout of the lines in terms of position, depth, steel thickness and joint design. (orig.)

  15. Decomposition of forest products buried in landfills

    International Nuclear Information System (INIS)

    Highlights: • This study tracked chemical changes of wood and paper in landfills. • A decomposition index was developed to quantify carbohydrate biodegradation. • Newsprint biodegradation as measured here is greater than previous reports. • The field results correlate well with previous laboratory measurements. - Abstract: The objective of this study was to investigate the decomposition of selected wood and paper products in landfills. The decomposition of these products under anaerobic landfill conditions results in the generation of biogenic carbon dioxide and methane, while the un-decomposed portion represents a biogenic carbon sink. Information on the decomposition of these municipal waste components is used to estimate national methane emissions inventories, for attribution of carbon storage credits, and to assess the life-cycle greenhouse gas impacts of wood and paper products. Hardwood (HW), softwood (SW), plywood (PW), oriented strand board (OSB), particleboard (PB), medium-density fiberboard (MDF), newsprint (NP), corrugated container (CC) and copy paper (CP) were buried in landfills operated with leachate recirculation, and were excavated after approximately 1.5 and 2.5 yr. Samples were analyzed for cellulose (C), hemicellulose (H), lignin (L), volatile solids (VS), and organic carbon (OC). A holocellulose decomposition index (HOD) and carbon storage factor (CSF) were calculated to evaluate the extent of solids decomposition and carbon storage. Samples of OSB made from HW exhibited cellulose plus hemicellulose (C + H) loss of up to 38%, while loss for the other wood types was 0–10% in most samples. The C + H loss was up to 81%, 95% and 96% for NP, CP and CC, respectively. The CSFs for wood and paper samples ranged from 0.34 to 0.47 and 0.02 to 0.27 g OC g−1 dry material, respectively. These results, in general, correlated well with an earlier laboratory-scale study, though NP and CC decomposition measured in this study were higher than

  16. Investigating buried polymer interfaces using sum frequency generation vibrational spectroscopy

    OpenAIRE

    Chen, Zhan

    2010-01-01

    This paper reviews recent progress in the studies of buried polymer interfaces using sum frequency generation (SFG) vibrational spectroscopy. Both buried solid/liquid and solid/solid interfaces involving polymeric materials are discussed. SFG studies of polymer/water interfaces show that different polymers exhibit varied surface restructuring behavior in water, indicating the importance of probing polymer/water interfaces in situ. SFG has also been applied to the investigation of interfaces b...

  17. Multicrystalline and Back Contact Buried Contact Silicon Solar Cells

    OpenAIRE

    Jooß, Wolfgang

    2002-01-01

    This thesis examines multicrystalline silicon (mc-Si) as well as back contact silicon solar cells applying the Buried Contact Solar Cell (BCSC) technology. In this metallisation approach, the electrical contacts are buried into the silicon wafer leading to low shadowing losses in conjunction with highly conducting contact fingers. Further features include a selective emitter structure as well as surface passivation. A baseline process for the manufacturing of BCSC was developed which includes...

  18. Magnetism based System for Detecting and Identifying buried Networks

    OpenAIRE

    Sultan Buzid; Danielle Nuzillard; Fabien Belloir; Larbi Beheim; Jean-Louis Nicolas

    2009-01-01

    An innovative magnetic based system for detectingand identifying networks of buried pipes is presented. Currentlywhen a pipe is buried, a warning colored plastic is placed aboveit and its color indicates the nature of its fluid. Its locationis reported on maps. This system developed here consists ofa magnetic sensor block associated to a detector based on anelectromagnetic induction balance. The detector emits a sine waveof frequency f0 and picks up the harmonics generated by thepossible pres...

  19. Compact Buried Ducts in a Hot-Humid Climate House

    Energy Technology Data Exchange (ETDEWEB)

    Mallay, D. [Home Innovation Research Labs, Upper Marlboro, MD (United States)

    2016-01-01

    A system of compact, buried ducts provides a high-performance and cost-effective solution for delivering conditioned air throughout the building. This report outlines research activities that are expected to facilitate adoption of compact buried duct systems by builders. The results of this research would be scalable to many new house designs in most climates and markets, leading to wider industry acceptance and building code and energy program approval.

  20. Defensive burying in rodents: ethology, neurobiology and psychopharmacology

    OpenAIRE

    De Boer, SF; Koolhaas, JA

    2003-01-01

    Defensive burying refers to the typical rodent behavior of displacing bedding material with vigorous treading-like movements of their forepaws and shoveling movements of their heads directed towards a variety of noxious stimuli that pose a near and immediate threat, such as a wall-mounted electrified shock-prod. Since its introduction 25 years ago by Pinel and Treit [J. Comp. Physiol. Psychol. 92 (1978) 708], defensive (shock-prod) burying has been the focus of a considerable amount of resear...

  1. Review of Concrete Biodeterioration in Relation to Buried Nuclear Waste

    Energy Technology Data Exchange (ETDEWEB)

    Turick, C; Berry, C.

    2012-10-15

    Long-term storage of low level radioactive material in below ground concrete disposal units (DUs) (Saltstone Disposal Facility) is a means of depositing wastes generated from nuclear operations of the U.S. Department of Energy. Based on the currently modeled degradation mechanisms, possible microbial induced effects on the structural integrity of buried low level wastes must be addressed. Previous international efforts related to microbial impacts on concrete structures that house low level radioactive waste showed that microbial activity can play a significant role in the process of concrete degradation and ultimately structural deterioration. This literature review examines the recent research in this field and is focused on specific parameters that are applicable to modeling and prediction of the fate of concrete vaults housing stored wastes and the wastes themselves. Rates of concrete biodegradation vary with the environmental conditions, illustrating a need to understand the bioavailability of key compounds involved in microbial activity. Specific parameters require pH and osmotic pressure to be within a certain range to allow for microbial growth as well as the availability and abundance of energy sources like components involved in sulfur, iron and nitrogen oxidation. Carbon flow and availability are also factors to consider in predicting concrete biodegradation. The results of this review suggest that microbial activity in Saltstone, (grouted low level radioactive waste) is unlikely due to very high pH and osmotic pressure. Biodegradation of the concrete vaults housing the radioactive waste however, is a possibility. The rate and degree of concrete biodegradation is dependent on numerous physical, chemical and biological parameters. Results from this review point to parameters to focus on for modeling activities and also, possible options for mitigation that would minimize concrete biodegradation. In addition, key chemical components that drive microbial

  2. Study of novel techniques for reducing self-heating effects in SOI power LDMOS

    Science.gov (United States)

    Roig, J.; Flores, D.; Hidalgo, S.; Vellvehi, M.; Rebollo, J.; Millán, J.

    2002-12-01

    Self-heating effects in silicon-on-insulator (SOI) power devices have become a serious problem when the active silicon layer thickness is reduced and buried oxide thickness is increased. Hence, if the temperature of the active region rises, the device electrical characteristics can be seriously modified in steady state and transient modes. In order to alleviate the self heating, two novel techniques which lead to a better heat flow from active silicon layer to silicon substrate through the buried oxide layer in SOI power devices are proposed. No significant changes on device electrical characteristics are expected with the inclusion of the novel techniques. The electro-thermal performance of lateral power devices including the proposed techniques is also presented.

  3. Study of novel techniques for reducing self-heating effects in SOI power LDMOS

    Energy Technology Data Exchange (ETDEWEB)

    Roig, J.; Flores, D.; Hidalgo, S.; Vellvehi, M.; Rebollo, J.; Millan, J. [Centro Nacional de Microelectronica (CNM-CSIC), Barcelona (Spain)

    2002-12-01

    Self-heating effects in silicon-on-insulator (SOI) power devices have become a serious problem when the active silicon layer thickness is reduced and buried oxide thickness is increased. Hence, if the temperature of the active region rises, the device electrical characteristics can be seriously modified in steady state and transient modes. In order to alleviate the self heating, two novel techniques which lead to a better heat flow from active silicon layer to silicon substrate through the buried oxide layer in SOI power devices are proposed. No significant changes on device electrical characteristics are expected with the inclusion of the novel techniques. The electro-thermal performance of lateral power devices including the proposed techniques is also presented. (Author)

  4. Buried bumber syndrome (internal button buried of the gastrostomy): Unearthing the solution

    International Nuclear Information System (INIS)

    The Buried bumper syndrome is a major complication of percutaneous endoscopic gastrostomy and the literature of in of having described of rarely. The physiopathology is the gastric isquemy of the mucous one for an excessive pressure for the ends that fix the gastrostomy. Their clinical manifestations that depend on the depth of migration of the end go from the absence of symptoms, spill of the nutrition enteral being the most frequent, until peritonitis. The diverse described treatment modalities are based on the depth of migration of the end valued endoscopically. The successful use of the ecoendosonography is described for the estimate of the depth of the migration, when you cannot visualize the end internal endoscopically and we propose a handling .algorithm based on this technique

  5. Temperature dependency of double material gate oxide (DMGO) symmetric dual-k spacer (SDS) wavy FinFET

    Science.gov (United States)

    Pradhan, K. P.; Priyanka; Sahu, P. K.

    2016-01-01

    Symmetric Dual-k Spacer (SDS) Trigate Wavy FinFET is a novel hybrid device that combines three significant and advanced technologies i.e., ultra-thin-body (UTB), FinFET, and symmetric spacer engineering on a single silicon on insulator (SOI) platform. This innovative architecture promises to enhance the device performance as compared to conventional FinFET without increasing the chip area. For the first time, we have incorporated two different dielectric materials (SiO2, and HfO2) as gate oxide to analyze the effect on various performance metrics of SDS wavy FinFET. This work evaluates the response of double material gate oxide (DMGO) on parameters like mobility, on current (Ion), transconductance (gm), transconductance generation factor (TGF), total gate capacitance (Cgg), and cutoff frequency (fT) in SDS wavy FinFET. This work also reveals the presence of biasing point i.e., zero temperature coefficient (ZTC) bias point. The ZTC bias point is that point where the device parameters become independent of temperature. The impact of operating temperature (T) on above said various performances are also subjected to extensive analysis. This further validates the reliability of DMGO-SDS FinFET and its application opportunities involved in modeling analog/RF circuits for a broad range of temperature applications. From extensive 3-D device simulation, we have determined that the inclusion of DMGO in SDS wavy FinFET is superior in performance.

  6. Buried waste integrated demonstration FY 94 deployment plan

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) is a program funded by the U.S. Department of Energy Office of Technology Development. BWID supports the applied research, development, demonstration, testing, and evaluation of a suite of advanced technologies that together form a comprehensive remediation system for the effective and efficient remediation of buried waste. The fiscal year (FY) 1994 effort will fund thirty-eight technologies in five areas of buried waste site remediation: site characterization, waste characterization, retrieval, treatment, and containment/stabilization. This document is the basic operational planning document for deployment of all BWID projects. Discussed in this document are the BWID preparations for INEL field demonstrations, INEL laboratory demonstrations, non-INEL demonstrations, and paper studies. Each technology performing tests will prepare a test plan to detail the specific procedures, objectives, and tasks of each test. Therefore, information specific to testing each technology is intentionally omitted from this document

  7. A Review of Buried Piping Management in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Over the past several years, instances of buried piping leaks have occurred in safety-related and nonsafety related piping at nuclear power plants. Buried piping systems are used for fire suppression, radiation waste treatment, or component cooling. This piping may be either concrete or metal. For example, nuclear power plants require an external heat sink, such as a lake or river, in order to maximize thermal cycle efficiencies and provide an ultimate safety heat sink. Typically, the piping between these heat sinks and the plant secondary cooling loop is known as raw water piping. Degradation of raw water piping affects the plant's ability to remove excess heat in case of an accident. Access to these pipes could be extremely limited. In this paper, various issues and activities related to buried piping are discussed

  8. Remote characterization system for subsurface mapping of buried waste sites

    International Nuclear Information System (INIS)

    Mapping of buried objects and chemical and radiological contamination is required at US Department of Energy (DOE) buried waste sites. The DOE Office of Technology Development's robotics integrated program has initiated a project to develop and demonstrate a remotely controlled sensor and vehicle system, named the remote characterization system (RCS) to obtain highly precise and timely subsurface data to support characterization of waste sites. Site characterization surveys using the RCS will be safer, more cost effective, more accurate, and more complete than surveys being performed with current methods. The RCS project is staffed by a coordinated team from five DOE laboratories and will produce meaningful demonstrations at buried waste sites within the next 2 yr. An advisory group composed of site users and technologists has been identified to ensure that the RCS is responsive to site user requirements. Technology transfer to potential users and to industry is planned as part of the program

  9. End effectors and attachments for buried waste excavation equipment

    Energy Technology Data Exchange (ETDEWEB)

    King, R.H.

    1993-09-01

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a suite of advanced technologies that form a comprehensive remediation system for the effective and efficient remediation of buried waste. Their efforts are identified and coordinated in support of the U.S. Department of Energy (DOE), Environmental Restoration and Waste Management (ER&WM) Department`s needs and objectives. The present focus of BWID is to support retrieval and ex-situ treatment configuration options. Future activities will explore and support containment, and stabilization efforts in addition to the retrieval/ex situ treatment options. This report presents a literature search on the state-of-the-art in end effectors and attachments in support of excavator of buried transuranic waste. Included in the report are excavator platforms and a discussion of the various attachments. Also included is it list of vendors and specifications.

  10. End effectors and attachments for buried waste excavation equipment

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a suite of advanced technologies that form a comprehensive remediation system for the effective and efficient remediation of buried waste. Their efforts are identified and coordinated in support of the U.S. Department of Energy (DOE), Environmental Restoration and Waste Management (ER ampersand WM) Department's needs and objectives. The present focus of BWID is to support retrieval and ex-situ treatment configuration options. Future activities will explore and support containment, and stabilization efforts in addition to the retrieval/ex situ treatment options. This report presents a literature search on the state-of-the-art in end effectors and attachments in support of excavator of buried transuranic waste. Included in the report are excavator platforms and a discussion of the various attachments. Also included is it list of vendors and specifications

  11. Buried waste integrated demonstration FY 94 deployment plan

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, R.A.; Walker, S.; Garcia, M.M.

    1994-05-01

    The Buried Waste Integrated Demonstration (BWID) is a program funded by the U.S. Department of Energy Office of Technology Development. BWID supports the applied research, development, demonstration, testing, and evaluation of a suite of advanced technologies that together form a comprehensive remediation system for the effective and efficient remediation of buried waste. The fiscal year (FY) 1994 effort will fund thirty-eight technologies in five areas of buried waste site remediation: site characterization, waste characterization, retrieval, treatment, and containment/stabilization. This document is the basic operational planning document for deployment of all BWID projects. Discussed in this document are the BWID preparations for INEL field demonstrations, INEL laboratory demonstrations, non-INEL demonstrations, and paper studies. Each technology performing tests will prepare a test plan to detail the specific procedures, objectives, and tasks of each test. Therefore, information specific to testing each technology is intentionally omitted from this document.

  12. Experimental research on buried pipe performances. Improvements and developments

    Energy Technology Data Exchange (ETDEWEB)

    Buscaglione, L.; Lambert, F.; Pasqualini, E. (Italgas SpA, Rome (Italy). Politecnico di Torino, Turin (Italy). Dipt. di Ingegneria Strutturale)

    Experimental research relevant to steel buried pipes (of the type used in natural gas distribution systems) was carried out in cooperation with the Polythecnic of Turin, Italy, during the period June 1985-October 1986. Methods to measure sollicitation induced by loads on the surface of buried pipe were improved by the adoption of suitable instrumentation. Three degrees of compactedness of backfilling and four different types of support were considered. Both longitudinal and circumferential stresses were detected. In any case, the effect of repeated loads was observed. A comparison between the experimental data and the theorical forecasts.

  13. Guided wave attenuation in coated pipes buried in sand

    Science.gov (United States)

    Leinov, Eli; Cawley, Peter; Lowe, Michael J. S.

    2016-02-01

    Long-range guided wave testing (GWT) is routinely used for the monitoring and detection of corrosion defects in above ground pipelines in various industries. The GWT test range in buried, coated pipelines is greatly reduced compared to aboveground pipelines due to energy leakage into the embedding soil. In this study, we aim to increase test ranges for buried pipelines. The effect of pipe coatings on the T(0,1) and L(0,2) guided wave attenuation is investigated using a full-scale experimental apparatus and model predictions. Tests are performed on a fusion-bonded epoxy (FBE)-coated 8" pipe, buried in loose and compacted sand over a frequency range of 10-35 kHz. The application of a low impedance coating is shown to effectively decouple the influence of the sand on the ultrasound leakage from the buried pipe. We demonstrate ultrasonic isolation of a buried pipe by coating the pipe with a Polyethylene (PE)-foam layer that has a smaller impedance than both pipe and sand and the ability to withstand the overburden load from the sand. The measured attenuation in the buried PE-foam-FBE-coated pipe is substantially reduced, in the range of 0.3-1.2 dBm-1 for loose and compacted sand conditions, compared to buried FBE-coated pipe without the PE-foam, where the measured attenuation is in the range of 1.7-4.7 dBm-1. The acoustic properties of the PE-foam are measured independently using ultrasonic interferometry technique and used in model predictions of guided wave propagation in a buried coated pipe. Good agreement is found between the attenuation measurements and model predictions. The attenuation exhibits periodic peaks in the frequency domain corresponding to the through-thickness resonance frequencies of the coating layer. The large reduction in guided wave attenuation for PE-coated pipes would lead to greatly increased GWT test ranges, so such coatings would be attractive for new pipeline installations.

  14. Weak avalanche multiplication in SiGe heterojunction bipolar transistors on thin film silicon-on-insulator

    Institute of Scientific and Technical Information of China (English)

    Xu Xiao-Bo; Zhang He-Ming; Hu Hui-Yong; Li Yu-Chen; Qu Jiang-Tao

    2011-01-01

    In this paper,we propose an analytical avalanche multiplication model for the next generation of SiGe siliconon-insulator (SOI) heterojunction bipolar transistors (HBTs) and consider their vertical and lateral impact ionizations for the first time.Supported by experimental data,the analytical model predicts that the avalanche multiplication governed by impact ionization shows kinks and the impact ionization effect is small compared with that of the bulk HBT,resulting in a larger base-collector breakdown voltage.The model presented in the paper is significant and has useful applications in the design and simulation of the next generation of SiGe SOI BiCMOS technology.

  15. Compact electro-optic modulator on silicon-on-insulator substrates using cavities with ultra-small modal volumes

    Science.gov (United States)

    Schmidt, Bradley; Xu, Qianfan; Shakya, Jagat; Manipatruni, Sasikanth; Lipson, Michal

    2007-03-01

    We experimentally demonstrate a micron-size electro-optic modulator using a high-index-contrast silicon Fabry-Pérot resonator cavity. This compact device consists of a 1-D cavity formed within a single mode silicon channel waveguide and an embedded p-i-n junction on a silicon-oninsulator platform. The entire device is 6.0 microns in length. We demonstrate modulation depths as large as 5.87 dB at speeds of 250 Mbps limited only by fabrication imperfections, with optimized theoretical speeds of several Gbps.

  16. Mach-Zehnder Interferometer Biochemical Sensor Based on Silicon-on-Insulator Rib Waveguide with Large Cross Section

    Directory of Open Access Journals (Sweden)

    Dengpeng Yuan

    2015-08-01

    Full Text Available A high-sensitivity Mach-Zehnder interferometer (MZI biochemical sensing platform based on Silicon-in-insulator (SOI rib waveguide with large cross section is proposed in this paper. Based on the analyses of the evanescent field intensity, the mode polarization and cross section dimensions of the SOI rib waveguide are optimized through finite difference method (FDM simulation. To realize high-resolution MZI read-out configuration based on the SOI rib waveguide, medium-filled trenches are employed and their performances are simulated through two-dimensional finite-difference-time domain (2D-FDTD method. With the fundamental EH-polarized mode of the SOI rib waveguide with a total rib height of 10 μm, an outside rib height of 5 μm and a rib width of 2.5 μm at the operating wavelength of 1550 nm, when the length of the sensitive window in the MZI configuration is 10 mm, a homogeneous sensitivity of 7296.6%/refractive index unit (RIU is obtained. Supposing the resolutions of the photoelectric detectors connected to the output ports are 0.2%, the MZI sensor can achieve a detection limit of 2.74 × 10−6 RIU. Due to high coupling efficiency of SOI rib waveguide with large cross section with standard single-mode glass optical fiber, the proposed MZI sensing platform can be conveniently integrated with optical fiber communication systems and (opto- electronic systems, and therefore has the potential to realize remote sensing, in situ real-time detecting, and possible applications in the internet of things.

  17. High-performance and power-efficient 2${\\times}$2 optical switch on Silicon-on-Insulator

    CERN Document Server

    Han, Zheng; Checoury, Xavier; Bourderionnet, Jérôme; Boucaud, Philippe; De Rossi, Alfredo; Combrié, Sylvain

    2015-01-01

    A compact (15{\\mu}m${\\times}${\\mu}m) and highly-optimized 2${\\times}$2 optical switch is demonstrated on a CMOS-compatible photonic crystal technology. On-chip insertion loss are below 1dB, static and dynamic contrast are 40dB and >20dB respectively. Owing to efficient thermo-optic design, the power consumption is below 3 mW while the switching time is 1 {\\mu}s.

  18. Structural characterization of a bonded silicon-on-insulator layer with voids by micro-Raman spectroscopy

    OpenAIRE

    Usami, Akira; Ichimura, Masaya; Wada, Takao; Ishigami, Shun-ichiro; イチムラ, マサヤ; 市村, 正也

    1994-01-01

    Crystalline quality in a void region of a bonded silicon‐on‐insulator (SOI) wafer is evaluated by micro‐Raman spectroscopy. Downshifting and broadening of the Si optical‐phonon peak are observed at the edge of the void, while spectra within the void are little different from those outside the void. Comparison with calculated results based on the theory of the phonon localization shows that both the shift and the broadening are mainly due to structural disorder and not strain. Electrical prope...

  19. Strain reduction in selectively grown CdTe by MBE on nanopatterned silicon on insulator (SOI) substrates

    OpenAIRE

    Bommena, R.; Seldrum, T.; Samain, Louise; Sporken, R.; Sivananthan, S.; S. R. J. Brueck

    2008-01-01

    Silicon-based substrates for the epitaxy of HgCdTe are an attractive low-cost choice for monolithic integration of infrared detectors with mature Si technology and high yield. However, progress in heteroepitaxy of CdTe/Si (for subsequent growth of HgCdTe) is limited by the high lattice and thermal mismatch, which creates strain at the heterointerface that results in a high density of dislocations. Previously we have reported on theoretical modeling of strain partitioning between CdTe and Si o...

  20. On-dimensional off-chip beam steering and shaping using optical phased arrays on silicon-on-insulator

    OpenAIRE

    Van Acoleyen, Karel; Komorowska, Katarzyna; Bogaerts, Wim; Baets, Roel

    2011-01-01

    Optical beam steering can find applications in several domains such as laser scanning, LiDAR (Light Detection And Ranging), wireless data transfer and optical switches and interconnects. As present beam steering approaches use mechanical motion such as moving mirrors or MEMS (Micro Electro Mechanical Systems) or molecular movement using liquid crystals, they are usually limited in speed and/or performance. Therefore we have studied the possibilities of the integrated silicon photonics platfor...

  1. Effect of Doping Position on the Active Silicon-on-Insulator Micro-Ring Resonator Based on Free Carrier Injection

    Directory of Open Access Journals (Sweden)

    B. Mardiana

    2012-01-01

    Full Text Available Problem statement: Metal interconnects have become significant limitation on the scaling of CMOS technologies in electronics integrated circuit. Silicon photonics has offers great potential to overcome this critical bottleneck due to the advantages of optical interconnects. Silicon-based optical micro-ring resonator is promising basic element of future electronic-photonic integrated circuits because of its wide applications on photonic devices such as modulator, switch and sensor. Approach: This study highlights the study of the free carrier injection effect on the active SOI micro-ring resonator. The effect of the free carrier injection on micro-ring resonator is evaluated by varying the p+ and n+ doping position. Device performances are predicted using numerical modeling software 2D SILVACO as well as Finite Difference Time Domain (FDTD simulation software, RSOFT. Results: The results show that the refractive index change increases as the p+ and n+ doping position become closer to the rib waveguide. A shift in resonant wavelength of around 2 and 3 nm was is predicted at 0.9V drive forward voltage for 0.5 and 1.0 μm gap distance between p+ and n+ doping regions and the sidewall of the rib waveguide. It is also shown that 10 and 9.2 dB maximum change of the output response obtained through the output of the transmission spectrum of the device with gap 0.5 and 1.0 μm. Conclusion: The closer distance between p+ and n+ doping regions and the rib waveguide has optimal shift of resonance wavelength and better extinction ratio of transmission spectrum.

  2. Special features of the formation of the wave relief laser recrystallisation of structures of the 'silicon-on-insulator' type

    International Nuclear Information System (INIS)

    The aim of this work was to investigate the mechanism of formation of a periodic wave relief on the surface of the silicon film after laser recrystallisation of the SOS structure in the direction of movement of the zone

  3. Note: A silicon-on-insulator microelectromechanical systems probe scanner for on-chip atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, Anthony G.; Maroufi, Mohammad; Moheimani, S. O. Reza, E-mail: Reza.Moheimani@newcastle.edu.au [School of Electrical Engineering and Computer Science, University of Newcastle, Callaghan, NSW 2308 (Australia)

    2015-04-15

    A new microelectromechanical systems-based 2-degree-of-freedom (DoF) scanner with an integrated cantilever for on-chip atomic force microscopy (AFM) is presented. The silicon cantilever features a layer of piezoelectric material to facilitate its use for tapping mode AFM and enable simultaneous deflection sensing. Electrostatic actuators and electrothermal sensors are used to accurately position the cantilever within the x-y plane. Experimental testing shows that the cantilever is able to be scanned over a 10 μm × 10 μm window and that the cantilever achieves a peak-to-peak deflection greater than 400 nm when excited at its resonance frequency of approximately 62 kHz.

  4. Advancing the performance of one-dimensional photonic crystal/photonic wire micro-cavities in silicon-on-insulator

    OpenAIRE

    Md Zain, A.R.; Sorel, M.; De La Rue, R.M.

    2008-01-01

    We present new results that demonstrate advances in the performance achievable in photonic crystal/photonic wire micro-cavities. In one example, a quality-factor value as high as 147,000 has been achieved experimentally at a useful transmission level.

  5. Mach-Zehnder Interferometer Biochemical Sensor Based on Silicon-on-Insulator Rib Waveguide with Large Cross Section.

    Science.gov (United States)

    Yuan, Dengpeng; Dong, Ying; Liu, Yujin; Li, Tianjian

    2015-01-01

    A high-sensitivity Mach-Zehnder interferometer (MZI) biochemical sensing platform based on Silicon-in-insulator (SOI) rib waveguide with large cross section is proposed in this paper. Based on the analyses of the evanescent field intensity, the mode polarization and cross section dimensions of the SOI rib waveguide are optimized through finite difference method (FDM) simulation. To realize high-resolution MZI read-out configuration based on the SOI rib waveguide, medium-filled trenches are employed and their performances are simulated through two-dimensional finite-difference-time domain (2D-FDTD) method. With the fundamental EH-polarized mode of the SOI rib waveguide with a total rib height of 10 μm, an outside rib height of 5 μm and a rib width of 2.5 μm at the operating wavelength of 1550 nm, when the length of the sensitive window in the MZI configuration is 10 mm, a homogeneous sensitivity of 7296.6%/refractive index unit (RIU) is obtained. Supposing the resolutions of the photoelectric detectors connected to the output ports are 0.2%, the MZI sensor can achieve a detection limit of 2.74 × 10(-6) RIU. Due to high coupling efficiency of SOI rib waveguide with large cross section with standard single-mode glass optical fiber, the proposed MZI sensing platform can be conveniently integrated with optical fiber communication systems and (opto-) electronic systems, and therefore has the potential to realize remote sensing, in situ real-time detecting, and possible applications in the internet of things. PMID:26343678

  6. Baseline tests for arc melter vitrification of INEL buried wastes. Volume II: Baseline test data appendices

    Energy Technology Data Exchange (ETDEWEB)

    Oden, L.L.; O`Conner, W.K.; Turner, P.C.; Soelberg, N.R.; Anderson, G.L.

    1993-11-19

    This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc melting furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.

  7. Buried homojunction solar cells formed in p-InP during sputter deposition and hydrogen plasma processing

    Science.gov (United States)

    Gessert, T. A.; Li, X.; Wanlass, M. W.; Coutts, T. J.

    1990-01-01

    Although it is apparent that direct current (DC) magnetron sputter deposition of indium tin oxide (ITO) leads to the formation of a buried homojunction in single-crystal p-type InP, the actual mechanism of type conversion of the InP surface is not clear. Since sputter deposition of In2O3 has also led to high-quality cells, it appears that Sn is not the cause of type conversion. To investigate the junction formation process further, experiments involving the use of a pure hydrogen plasma have been performed, resulting in type conversion of Fe-doped InP surfaces and in solar cells with efficiencies over 16 percent (global). The results confirm that sputter deposition is not necessary to form this type of buried homojunction solar cell, and they suggest a fabrication process that may be used with other relevant photovoltaic materials.

  8. 49 CFR 195.248 - Cover over buried pipeline.

    Science.gov (United States)

    2010-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Construction § 195.248 Cover over buried pipeline. (a) Unless specifically... the pipe and the ground level, road bed, river bottom, or underwater natural bottom (as determined...

  9. Ground Penetrating Radar Imaging of Buried Metallic Objects

    DEFF Research Database (Denmark)

    Polat, A. Burak; Meincke, Peter

    During the past decade there has been considerable research on ground penetrating radar (GPR) tomography for detecting objects such as pipes, cables, mines and barrels buried under the surface of the Earth. While the earlier researches were all based on the assumption of a homogeneous background...

  10. Risk and cost tradeoffs for remote retrieval of buried waste

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration is supporting the development, demonstration, testing, and evaluation of a suite of technologies that, when integrated with commercially available technologies, form a comprehensive system for the remediation of radioactive and hazardous buried waste. As a part of the program's technology development, remote retrieval equipment is being developed and tested for the remediation of buried waste. During remedial planning, several factors are considered when choosing remote versus manual retrieval systems. Time that workers are exposed to radioactivity, chemicals, air particulate, and industrial hazards is one consideration. The generation of secondary waste is also a consideration because it amounts to more waste to treat and some wastes may require special handling or treatment. Cost is also a big factor in determining whether remote or manual operations will be used. Other considerations include implementability, effectiveness, and the number of required personnel. This paper investigates each of these areas to show the risk and cost benefits and limitations for remote versus manual retrieval of buried waste

  11. Defensive burying in rodents : ethology, neurobiology and psychopharmacology

    NARCIS (Netherlands)

    De Boer, SF; Koolhaas, JA

    2003-01-01

    Defensive burying refers to the typical rodent behavior of displacing bedding material with vigorous treading-like movements of their forepaws and shoveling movements of their heads directed towards a variety of noxious stimuli that pose a near and immediate threat, such as a wall-mounted electrifie

  12. Mapping suspected buried channels using gravity: Examples from southwest Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Keighley, K.E.; Atekwana, E.A.; Sauck, W.A. (Western Michigan Univ., Kalamazoo, MI (United States). Dept. of Geology)

    1994-04-01

    This study documents the successful application of the gravity method in mapping suspected buried bedrock valleys at three sites in southwest Michigan. The first site is located in Benton Harbor, Berrien County. Gravity surveys were conducted along the Jean Klock Park as part of an ongoing coastal research study of the Lake Michigan shoreline. Previous Ground Penetrating Radar (GPR) studies at this site had suggested the presence of a buried valley. The results of the gravity survey confirmed the existence of a buried valley approximately 30--40 m deep and at least 2,000 m wide, which is in good agreement with information from drill cores suggesting a possible ancient river system. A detailed gravity survey was conducted at the second site located in Schoolcraft Township, Kalamazoo County, where the heavy use of pesticides has resulted in the contamination of the upper aquifers. Preliminary results suggest the presence of a broad shallow valley at least 25 m deep. Gravity surveys at the third site located southeast of the Kavco Landfill, Barry County also suggests the presence of a buried valley oriented NE-SW, confirming the interpretations of an earlier electrical resistivity study. It is possible that this channel controls groundwater flow and facilitates the transport of contaminants from the landfill to the surrounding areas.

  13. Melter development needs assessment for RWMC buried wastes

    International Nuclear Information System (INIS)

    This report presents a survey and initial assessment of the existing state-of-the-art melter technology necessary to thermally treat (stabilize) buried TRU waste, by producing a highly leach resistant glass/ceramic waste form suitable for final disposal. Buried mixed transuranic (TRU) waste at the Idaho National Engineering Laboratory (INEL) represents an environmental hazard requiring remediation. The Environmental Protection Agency (EPA) placed the INEL on the National Priorities List in 1989. Remediation of the buried TRU-contaminated waste via the CERCLA decision process is required to remove INEL from the National Priorities List. A Waste Technology Development (WTD) Preliminary Systems Design and Thermal Technologies Screening Study identified joule-heated and plasma-heated melters as the most probable thermal systems technologies capable of melting the INEL soil and waste to produce the desired final waste form [Iron-Enriched Basalt (IEB) glass/ceramic]. The work reported herein then surveys the state of existing melter technology and assesses it within the context of processing INEL buried TRU wastes and contaminated soils. Necessary technology development work is recommended

  14. Buried Waste Integrated Demonstration Technology Preparedness and Status Report Guidance

    International Nuclear Information System (INIS)

    A Technology Preparedness and Status Report is required for each Technical Task Plan funded by the Buried Waste Integrated Demonstration. This document provides guidance for the preparation of that report. Major sections of the report will include a subset of the need for the technology, objectives of the demonstration, technology description and readiness evaluation, demonstration requirements, and preparedness checklist and action plan

  15. Risk and cost tradeoffs for remote retrieval of buried waste

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, R.A.; Grienbenow, B.E.; Nickelson, D.F.

    1994-12-31

    The Buried Waste Integrated Demonstration is supporting the development, demonstration, testing, and evaluation of a suite of technologies that, when integrated with commercially available technologies, form a comprehensive system for the remediation of radioactive and hazardous buried waste. As a part of the program`s technology development, remote retrieval equipment is being developed and tested for the remediation of buried waste. During remedial planning, several factors are considered when choosing remote versus manual retrieval systems. Time that workers are exposed to radioactivity, chemicals, air particulate, and industrial hazards is one consideration. The generation of secondary waste is also a consideration because it amounts to more waste to treat and some wastes may require special handling or treatment. Cost is also a big factor in determining whether remote or manual operations will be used. Other considerations include implementability, effectiveness, and the number of required personnel. This paper investigates each of these areas to show the risk and cost benefits and limitations for remote versus manual retrieval of buried waste.

  16. Development of a teleoperated backhoe for buried waste excavation

    International Nuclear Information System (INIS)

    For nearly five decades the United States (US) Department of Energy (DOE) and its predecessor agencies have engaged in broad-based research and development activities as well as nuclear weapons component production. As a by-product of these activities, large quantities of waste materials have been granted. One of the most common approaches used for solid waste storage was to bury waste containers in pits and trenches. With the current emphasis on environmental restoration, DOE now plans to either retrieve much of the legacy of buried waste or stabilize the waste in place via in situ vitrification or other means. Because of the variety of materials that have been buried over the years, the hazards of retrieval are significant if performed using conventional manned operations. The potential hazards, in addition to radiation exposure, include pyrophorics, toxic chemicals, and explosives. Although manifests exist for much of the buried waste, these records are often incomplete compared to today's requirements. Because of the potential hazards and uncertainty about waste contents and container integrity, it is highly desirable to excavate these wastes using remotely operated equipment. In this paper the authors describe the development of a teleoperated military tractor called the Small Emplacement Excavator (SEE). Development of the SEE is being funded jointly by both DOE and the US Army. The DOE sponsor is the Office of Technology Development (OTD) Robotics Program. The US Army sponsor is the Program Manager for Ammunition Logistics, Picatinny Arsenal. The primary interest for DOE is in the application to remote excavation of buried waste, while the primary emphasis for the US Army is in the remote retrieval of unexploded ordnance. Technical requirements for these two tasks are very similar and, therefore, justify a joint development project. 1 ref

  17. A system to control contamination during retrieval of buried TRU waste

    International Nuclear Information System (INIS)

    This paper discusses design features of a contamination control system for use during retrieval of buried transuranic (TRU) waste at the Idaho National Engineering Laboratory (INEL). Between 1952 and 1970 over 56,000m3 of primarily Rocky Mats Plant (RFP) generated TRU waste was stored at the INEL in shallow land filled pits and trenches, which consisted of sludges, cloth, paper, metal, wood, concrete, and asphalt contaminated with micron-sized, oxidized particles of plutonium and americium. Retrieval for final disposal is one of the options being considered for this buried waste. This contamination control system is an important subsystem of an overall retrieval system design involving containment buildings, remotely controlled excavators and transporters, separation systems, and final disposal options. The main contaminants to be controlled are plutonium and americium compounds associated with the TRU waste. The contamination control system is comprised of the Dust Suppression System (DSS) and a Rapid Monitoring System (RMS). The DSS is a grouping of subsystems including: (a) the inner building laminar flow ventilation system (b) the Lifting and Moving System (LAMS) which provides mobility for (c) the Contamination Suppression System (CSS). The RMS consists of state-of-the-art air monitors and detection systems for measuring loose contamination. To complement and guide the design effort, engineering background experimental studies were performed on the DSS and RMS. The results of these studies are summarized along with a discussion of the general design features. 6 refs., 1 fig

  18. Seismic response of buried pipelines: a state-of-the-art review

    International Nuclear Information System (INIS)

    A state-of-the-art review of the seismic response of buried pipelines is presented. The review includes modeling of soil-pipe system and seismic excitation, methods of response analysis of buried pipelines, seismic behavior of buried pipelines under different parametric variations, seismic stresses at the bends and intersections of network of pipelines. pipe damage in earthquakes and seismic risk analysis of buried pipelines. Based on the review, the future scope of work on the subject is outlined. (orig.)

  19. Electronic Structure of Buried Interfaces - Oral Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Zachary [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-25

    In the electronics behind computer memory storage, the speed and size are dictated by the performance of permanent magnets inside devices called read heads. Complicated magnets made of stacked layers of thin films can be engineered to have properties that yield more energy storage and faster switching times compared to conventional iron or cobalt magnets. The reason is that magnetism is a result of subtle interactions amongst electrons; just how neurons come together on large scales to make cat brains and dog brains, ensembles of electrons interact and become ferromagnets and paramagnets. These interactions make magnets too difficult to study in their entirety, so I focus on the interfaces between layers, which are responsible for the coupling materials physicists hope to exploit to produce next-generation magnets. This project, I study a transition metal oxide material called LSCO, Lanthanum Cobaltite, which can be a paramagnet or a ferromagnet depending on how you tweak the electronic structure. It exhibits an exciting behavior: its sum is greater than the sum of its parts. When another similar material called a LSMO, Lanthanum Manganite, is grown on top of it, their interface has a different type of magnetism from the LSCO or the LSMO! I hope to explain this by demonstrating differently charged ions in the interface. The typical method for quantifying this is x-ray absorption, but all conventional techniques look at every layer simultaneously, averaging the interfaces and the LSCO layers that we want to characterize separately. Instead, I must use a new reflectivity technique, which tracks the intensity of reflected x-rays at different angles, at energies near the absorption peaks of certain elements, to track changes in the electronic structure of the material. The samples were grown by collaborators at the Takamura group at U.C. Davis and probed with this “resonant reflectivity” technique on Beamline 2-1 at the Stanford Synchrotron Radiation Lightsource

  20. Electromagnetic response of buried cylindrical structures for line current excitation

    Science.gov (United States)

    Pajewski, Lara; Ponti, Cristina

    2013-04-01

    The Cylindrical-Wave Approach (CWA) rigorously solves, in the spectral domain, the electromagnetic forward scattering by a finite set of buried two-dimensional perfectly-conducting or dielectric objects [1]-[2]. In this technique, the field scattered by underground objects is represented in terms of a superposition of cylindrical waves. Use is made of the plane-wave spectrum [1] to take into account the interaction of such waves with the planar interface between air and soil, and between different layers eventually present in the ground [3]. Obstacles of general shape can be simulated through the CWA with good results, by using a suitable set of small circular-section cylinders [4]. Recently, we improved the CWA by facing the fundamental problem of losses in the ground [5]: this is of significant importance in remote-sensing applications, since real soils often have complex permittivity and conductivity, and sometimes also a complex permeability. While in previous works concerning the CWA a monochromatic or pulsed plane-wave incident field was considered, in the present work a different source of scattering is present: a cylindrical wave radiated by a line source. Such a source is more suitable to model the practical illumination field used in GPR surveys. The electric field radiated by the line current is expressed by means of a first-kind Hankel function of 0-th order. The theoretical solution to the scattering problem is developed for both dielectric and perfectly-conducting cylinders buried in a dielectric half-space. The approach is implemented in a Fortran code; an accurate numerical evaluation of the involved spectral integrals is performed, the highly-oscillating behavior of the homogeneous waves is correctly followed and evanescent contributions are taken into account. The electromagnetic field scattered in both air and ground can be obtained, in near- and far-field regions, for arbitrary radii and permittivity of the buried cylinders, as well as for

  1. Sinusoidal Steady State Analysis on 4H-SiC Buried Channel MOSFETs

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tao; LU Hong-Liang; ZHANG Yi-Men; ZHANG Yu-Ming; YE Li-Hui

    2008-01-01

    With the combined use of the drift-diffusion (DD) model,experimental measured parameters and small-signal sinusoidal steady-state analysis,we extract the Y-parameters for 4H-SiC buried-channel metal oxide semiconductor field effect transistors (BCMOSFETs). Output short-circuit current gain G and Mason's invariant U are calculated for extrapolating unity current gain frequency in the common-source configuration fT and the maximum frequency of oscillation fmax,respectively.Here fT = 800 MHz and fmax = 5 GHz are extracted for the 4H-SiC BCMOSFETs,while the field effect mobility reaches its peak value 87cm2/Vs when VGs = 4.5 V.Simulation results clearly show that the characteristic frequency of 4H-SiC BCMOSFETs and field effect mobility are superior,due to the novel structure,compared with conventional MOSFETs.

  2. A new high-side and low-side LDMOST with a selective buried layer in the substrate

    Science.gov (United States)

    Cheng, Jianbing; Zhang, Bo; Sun, Weifeng; Shi, Longxing; Li, Zhaoji

    2014-12-01

    In this article, a novel low- and high-side lateral double-diffused metal-oxide-semiconductor field-effect-transistor (LDMOST) with an n-type selective buried layer (SBL-LDMOST) in a p-type substrate is presented. When the device operates in the high-side mode, the buried layer prevents vertical punch-through and then the vertical breakdown voltage (BV) is enhanced. When the device operates in the low-side mode, the depleted space-charges in the selective buried layer modulate the bulk electric field and then enhance the substrate to sustain higher reverse voltage. Simulation results show that the low-side BV increases from 585 V of the conventional LDMOST to 688 V and the high-side BV increases from 962 V to 1791 V at the same 60 μm drift region lengths condition. In addition, when operating in the high-side mode, the drive-current is not alleviated due to drift region immunity from depletion.

  3. Micromorphological and ultramicroscopic aspects of buried remains: Time-dependent markers of decomposition and permanence in soil in experimental burial.

    Science.gov (United States)

    Zangarini, Sara; Trombino, Luca; Cattaneo, Cristina

    2016-06-01

    A buried body not only determines an environmental response at the deposition site but it is also affected by the soil. The experiment was performed using eleven swine carcasses buried in an open site (Northern Italy). Changes occurring in bone tissue at different post-burial intervals were evaluated observing thin sections of bones through micromorphological and ultramicroscopic (SEM-EDS) techniques. These methods allowed the identification of: (a) magnesium phosphate (Mg3(PO4)2) crystallizations, probably linked to decomposition of bones and soft tissues; (b) significant sulphur levels which seem to be related to hydrogen sulphide (H2S) fixation in bone tissue; (c) metal oxide concentrations in the form of unusual violet-blue colorations, which probably are evidence of the soil's action and penetration in bones, also testified by (d) the presence of mineral grains enclosed in the osseous tissue. The results underline the possibility of identifying both time-dependent markers of decomposition and indicators of permanence in soil in buried bones. PMID:27081792

  4. Degradation of concrete buried in soil with aline ground water

    International Nuclear Information System (INIS)

    This study has been carried out to collect information on the degradation sequence of concrete buried in soil. We obtained concrete aged for 60 years and 100 years buried in soil saturated with saline ground water and investigated not only the physical properties but also the change in composition of the hydrated phases along the distance from the surface contacted with soil. Significant changes of pore size distribution, pH on concrete soak solution, CaO/Insoluble-fraction ratio of concrete, composition of hydrated phases and CaO/SiO2 ratio of C-S-H were observed along the distance from surface contacted with soil. From these results, it was possible to obtain important information for estimating the degradation sequence of concrete in soil saturated with saline ground water. (orig.)

  5. Buried Waste Integrated Demonstration lessons learned: 1993 technology demonstrations

    International Nuclear Information System (INIS)

    An integrated technology demonstration was conducted by the Buried Waste Integrated Demonstration (BWID) at the Idaho National Engineering Laboratory Cold Test Pit in the summer of 1993. This program and demonstration was sponsored by the US Department of Energy Office of Technology Development. The demonstration included six technologies representing a synergistic system for the characterization and retrieval of a buried hazardous waste site. The integrated technology demonstration proved very successful and a summary of the technical accomplishments is presented. Upon completion of the integrated technology demonstration, cognizant program personnel participated in a lessons learned exercise. This exercise was conducted at the Simplot Decision Support Center at Idaho State University and lessons learned activity captured additional information relative to the integration of technologies for demonstration purposes. This information will be used by BWID to enhance program planning and strengthen future technology demonstrations

  6. Field test plan: Buried waste technologies, Fiscal Year 1995

    International Nuclear Information System (INIS)

    The US Department of Energy, Office of Technology Development, supports the applied research, development, demonstration, testing, and evaluation of a suite of advanced technologies that, when integrated with commercially available baseline technologies, form a comprehensive remediation system for the effective and efficient remediation of buried waste. The Fiscal Year 1995 effort is to deploy and test multiple technologies from four functional areas of buried waste remediation: site characterization, waste characterization, retrieval, and treatment. This document is the basic operational planning document for the deployment and testing of the technologies that support the field testing in Fiscal Year 1995. Discussed in this document are the scope of the tests; purpose and objective of the tests; organization and responsibilities; contingency plans; sequence of activities; sampling and data collection; document control; analytical methods; data reduction, validation, and verification; quality assurance; equipment and instruments; facilities and utilities; health and safety; residuals management; and regulatory management

  7. Modeling of the Uplift Response of Buried Pipelines

    DEFF Research Database (Denmark)

    Choobbasti, Asskar Janalizadeh; Vahdatirad, Mohammadjavad; Firouzianbandpey, Sarah;

    2009-01-01

    Over the years, researchers have tried to understand the complex behavior of buried pipelines subjected to ground ruptures due to landslides, earthquakes, faults and uplift forces in shallow trenches. In an attempt to understand this complex behavior, an experimental investigation program has been...... carried out on uplift resistance of buried pipes. In this research, a new laboratory model is developed. Several tests have been performed by utilizing this laboratory model. Uplift forces due to raising water table causes the initiation of failure. Based on the data obtained two mechanisms are presented....... Mechanism of type one in which a sliding block with angled planes occurs in small displacements and in dense soil, and a mechanism of type two, circulation mechanism associated to soil flow under the pipe occurs in large displacement for dense soil and by continuing of loading and the soil around the pipe...

  8. Technology Solutions Case Study: Buried and Encapsulated Ducts, Jacksonville, Florida

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-11-01

    Ductwork installed in unconditioned attics can significantly increase the overall heating and cooling costs of residential buildings. In fact, estimated duct thermal losses for single-family residential buildings with ductwork installed in unconditioned attics range from 10% to 45%. In a study of three single-story houses in Florida, the Building America research team Consortium for Advanced Residential Buildings (CARB) investigated the strategy of using buried and/or encapsulated ducts (BED) to reduce duct thermal losses in existing homes. The BED strategy consists of burying ducts in loose-fill insulation and/or encapsulating them in closed cell polyurethane spray foam (ccSPF) insulation; specifically for use in humid climates.

  9. FY-94 buried waste integrated demonstration program report

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a multitude of advanced technologies. These technologies are being integrated to form a comprehensive remediation system for the effective and efficient remediation of buried waste. These efforts are identified and coordinated in support of the U.S. Department of Energy (DOE), Environmental Restoration and Waste Management (ER/WM) needs and objectives. This document summarizes previous demonstrations and describes the FY-94 BWID technology development and demonstration activities. Sponsored by the DOE Office of Technology Development (OTD), BWID works with universities and private industry to develop these technologies, which are being transferred to the private sector for use nationally and internationally. A public participation policy has been established to provide stakeholders with timely and accurate information and meaningful opportunities for involvement in the technology development and demonstration process

  10. Aeromagnetic Expression of Buried Basaltic Volcanoes Near Yucca Mountain, Nevada

    Science.gov (United States)

    O'Leary, D. W.; Mankinen, E.A.; Blakely, R.J.; Langenheim, V.E.; Ponce, D.A.

    2002-01-01

    A high-resolution aeromagnetic survey has defined a number of small dipolar anomalies indicating the presence of magnetic bodies buried beneath the surface of Crater Flat and the Amargosa Desert. Results of potential-field modeling indicate that isolated, small-volume, highly magnetic bodies embedded within the alluvial deposits of both areas produce the anomalies. Their physical characteristics and the fact that they tend to be aligned along major structural trends provide strong support for the hypothesis that the anomalies reflect buried basaltic volcanic centers. Other, similar anomalies are identified as possible targets for further investigation. High-resolution gravity and ground-magnetic surveys, perhaps along with drilling sources of selected anomalies and radiometric age determinations, can provide valuable constraints in estimating potential volcanic hazard to the potential nuclear waste repository at Yucca Mountain.

  11. Schedule optimization for IR detection of buried targets

    Science.gov (United States)

    Derzko, Zenon; Eylander, John B.; Broach, J. Thomas

    2012-06-01

    Schedule optimization of air platforms for IR sensors is a priority because of 1) the time sensitive nature of the IR detection of buried targets, 2) limited air platform assets, and 3) limited bandwidth for live-feed video. Scheduling optimization for airborne IR sensors depends on transient meteorological predictions, transient soil properties, target type and depth. This work involves using predictions from the Weather Research and Forecasting (WRF) model, a regional weather model, as input to the Countermine Computational Test Bed (CTB), a 3D finite element model that accounts for coupled heat and moisture transfer in soil and targets. The result is a continuous 2-day optimized schedule for airborne IR assets. In this paper, a 2-day optimized schedule for an airborne IR sensor asset is demonstrated for a single geographical location with a buried target. Transient physical surface and subsurface soil temperatures are presented as well as the phase-shifted, transient thermal response of the target.

  12. FY-94 buried waste integrated demonstration program report

    Energy Technology Data Exchange (ETDEWEB)

    1994-11-01

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a multitude of advanced technologies. These technologies are being integrated to form a comprehensive remediation system for the effective and efficient remediation of buried waste. These efforts are identified and coordinated in support of the U.S. Department of Energy (DOE), Environmental Restoration and Waste Management (ER/WM) needs and objectives. This document summarizes previous demonstrations and describes the FY-94 BWID technology development and demonstration activities. Sponsored by the DOE Office of Technology Development (OTD), BWID works with universities and private industry to develop these technologies, which are being transferred to the private sector for use nationally and internationally. A public participation policy has been established to provide stakeholders with timely and accurate information and meaningful opportunities for involvement in the technology development and demonstration process.

  13. Buried Porous Silicon-Germanium Layers in Monocrystalline Silicon Lattices

    Science.gov (United States)

    Fathauer, Robert W. (Inventor); George, Thomas (Inventor); Jones, Eric W. (Inventor)

    1998-01-01

    Monocrystalline semiconductor lattices with a buried porous semiconductor layer having different chemical composition is discussed and monocrystalline semiconductor superlattices with a buried porous semiconductor layers having different chemical composition than that of its monocrystalline semiconductor superlattice are discussed. Lattices of alternating layers of monocrystalline silicon and porous silicon-germanium have been produced. These single crystal lattices have been fabricated by epitaxial growth of Si and Si-Ge layers followed by patterning into mesa structures. The mesa structures are strain etched resulting in porosification of the Si-Ge layers with a minor amount of porosification of the monocrystalline Si layers. Thicker Si-Ge layers produced in a similar manner emitted visible light at room temperature.

  14. In situ grouting of buried transuranic waste with polyacrylamide

    International Nuclear Information System (INIS)

    This project is a demonstration and evaluation of the in situ hydrologic stabilization of buried transuranic waste at a humid site via grout injection. Two small trenches, containing buried transuranic waste, were filled with 34.000 L of polyacrylamide grout. Initial field results have indicated that voids within the trenches were totally filled by the grout and that the intratrench hydraulic conductivity was reduced to below field-measurable values. No evidence of grout constituents were observed in twelve perimeter groundwater monitoring wells indicating that grout was contained completely within the two trenches. Polyacrylamide grout was selected for field demonstration over the polyacrylate grout due to its superior performance in laboratory degradation studies. Also supporting the selection of polyacrylamide was the difficulty in controlling the set time of the acrylate polymerization. Based on preliminary degradation monitoring, the polyacrylamide was estimated to have a microbiological half-life of 362 years in the test soil. 15 refs., 9 figs., 12 tabs

  15. Buried object location based on frequency-domain UWB measurements

    International Nuclear Information System (INIS)

    In this paper, a wideband ground penetrating radar (GPR) system and a proposed frequency-domain data analysis technique are presented for the detection of shallow buried objects such as anti-personnel landmines. The GPR system uses one transmitting antenna and an array of six monopole receiving antenna elements and operates from 1 GHz to 20 GHz. This system is able to acquire, save and analyse data in the frequency domain. A common source or wide-angle reflection and refraction technique has been used for acquiring and processing the data. This technique is effective for the rejection of ground surface clutter. By applying the C-scan scheme, metallic and plastic mine-like targets buried in dry soil will be located

  16. Final Report: Imaging of Buried Nanoscale Optically Active Materials

    Energy Technology Data Exchange (ETDEWEB)

    Appelbaum, Ian

    2011-07-05

    This is a final report covering work done at University of Maryland to develop a Ballistic Electron Emission Luminescence (BEEL) microscope. This technique was intended to examine the carrier transport and photon emission in deeply buried optically-active layers and thereby provide a means for materials science to unmask the detailed consequences of experimentally controllable growth parameters, such as quantum dot size, statistics and orientation, and defect density and charge recombination pathways.

  17. Investigation of guided waves propagation in pipe buried in sand

    Energy Technology Data Exchange (ETDEWEB)

    Leinov, Eli; Cawley, Peter; Lowe, Michael J.S. [NDE Group, Department of Mechanical Engineering, Imperial College London, London SW7 2AZ (United Kingdom)

    2014-02-18

    The inspection of pipelines by guided wave testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the waves caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the propagation and attenuation characteristics of guided waves in pipes buried in fine sand using a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided waves are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of wave behavior in the buried pipe. We present the methodology and the systematic measurements of the guided waves under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided waves in buried pipes with a high level of confidence.

  18. Investigation of guided waves propagation in pipe buried in sand

    International Nuclear Information System (INIS)

    The inspection of pipelines by guided wave testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the waves caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the propagation and attenuation characteristics of guided waves in pipes buried in fine sand using a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided waves are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of wave behavior in the buried pipe. We present the methodology and the systematic measurements of the guided waves under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided waves in buried pipes with a high level of confidence

  19. Strategic management of health risks posed by buried transuranic wastes

    International Nuclear Information System (INIS)

    A strategy is presented for reducing health risks at sites contaminated with buried transuranic (TRU) wastes by first taking measures to immobilize the contaminants until the second step, final action, becomes cost-effective and poses less risk to the remediation workers. The first step of this strategy does not preclude further action if it is warranted and is in harmony with environmental laws and regulations

  20. Buried Waste Integrated Demonstration FY-95 Deployment Plan

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) is a program funded by the U.S. Department of Energy Office of Technology Development. BWID supports the applied research, development, demonstration, testing, and evaluation of a suite of advanced technologies that together form a comprehensive remediation system for the effective and efficient remediation of buried waste. The FY-95 effort will fund 24 technologies in five areas of buried waste site remediation: site characterization, waste characterization, retrieval, treatment, and containment/stabilization. Ten of these technologies will take part in the integrated field demonstration that will take place at the Idaho National Engineering Laboratory (INEL) facilities in the summer of 1995. This document is the basic operational planning document for deployment of all BWID projects funded in FY-95. Discussed in this document are the BWID preparations for the INEL integrated field demonstration, INEL research and development (R ampersand D) demonstrations, non-INEL R ampersand D demonstrations, and office research and technical review meetings. Each project will have a test plan detailing the specific procedures, objectives, and tasks of the test. Therefore, information that is specific to testing each technology is intentionally limited in this document

  1. Detection of buried objects using reflected GNSS signals

    Science.gov (United States)

    Notarpietro, Riccardo; De Mattia, Salvatore; Campanella, Maurizio; Pei, Yuekun; Savi, Patrizia

    2014-12-01

    The use of reflected Global Navigation Satellite System (GNSS) signals for sensing the Earth has been growing rapidly in recent years. This technique is founded on the basic principle of detecting GNSS signals after they have been reflected off the Earth's surface and using them to determine the properties of the reflecting surface remotely. This is the so-called GNSS reflectometry (GNSS-R) technique. In this paper, a new application regarding the detection of metallic buried objects is analyzed and it is validated through several experimental campaigns. Although the penetration depth of GNSS signals into the ground is not optimal and depends on the soil moisture, GNSS signals can likely interact approximately with the first 10 cm of the ground and therefore can be reflected back by any metallic object buried on the first terrain layer. A very light and low-cost GNSS receiver prototype based on a software-defined radio approach was developed. This receiver can be used as a payload on board small drones or unmanned aerial systems to detect metallic objects (mines or other explosive devices). A signal processing tool based on an open-loop GNSS signal acquisition strategy was developed. The results of two experiments which show the possibility of using GNSS-R signals to detect buried metallic objects and to provide an estimate of their dimensions are discussed.

  2. Degradation of carbohydrates and lignins in buried woods

    Science.gov (United States)

    Hedges, J.I.; Cowie, G.L.; Ertel, J.R.; James, Barbour R.; Hatcher, P.G.

    1985-01-01

    Spruce, alder, and oak woods deposited in coastal sediments were characterized versus their modern counterparts by quantification of individual neutral sugars and lignin-derived phenols as well as by scanning electron microscopy, 13C NMR, and elemental analysis. The buried spruce wood from a 2500 yr old deposit was unaltered whereas an alder wood from the same horizon and an oak wood from an open ocean sediment were profoundly degraded. Individual sugar and lignin phenol analyses indicate that at least 90 and 98 wt% of the initial total polysaccharides in the buried alder and oak woods, respectively, have been degraded along with 15-25 wt% of the lignin. At least 75% of the degraded biopolymer has been physically lost from these samples. This evidence is supported by the SEM, 13C NMR and elemental analyses, all of which indicate selective loss of the carbohydrate moiety. The following order of stability was observed for the major biochemical constituents of both buried hardwoods: vanillyl and p-hydroxyl lignin structural units > syringyl lignin structural units > pectin > ??-cellulose > hemicellulose. This sequence can be explained by selective preservation of the compound middle lamella regions of the wood cell walls. The magnitude and selectivity of the indicated diagenetic reactions are sufficient to cause major changes in the chemical compositions of wood-rich sedimentary organic mixtures and to provide a potentially large in situ nutrient source. ?? 1985.

  3. FY-95 technology catalog. Technology development for buried waste remediation

    International Nuclear Information System (INIS)

    The US Department of Energy's (DOE) Buried Waste Integrated Demonstration (BWID) program, which is now part of the Landfill Stabilization Focus Area (LSFA), supports applied research, development, demonstration, and evaluation of a multitude of advanced technologies dealing with underground radioactive and hazardous waste remediation. These innovative technologies are being developed as part of integrated comprehensive remediation systems for the effective and efficient remediation of buried waste sites throughout the DOE complex. These efforts are identified and coordinated in support of Environmental Restoration (EM-40) and Waste Management (EM-30) needs and objectives. Sponsored by the DOE Office of Technology Development (EM-50), BWID and LSFA work with universities and private industry to develop technologies that are being transferred to the private sector for use nationally and internationally. This report contains the details of the purpose, logic, and methodology used to develop and demonstrate DOE buried waste remediation technologies. It also provides a catalog of technologies and capabilities with development status for potential users. Past FY-92 through FY-94 technology testing, field trials, and demonstrations are summarized. Continuing and new FY-95 technology demonstrations also are described

  4. FY-95 technology catalog. Technology development for buried waste remediation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The US Department of Energy`s (DOE) Buried Waste Integrated Demonstration (BWID) program, which is now part of the Landfill Stabilization Focus Area (LSFA), supports applied research, development, demonstration, and evaluation of a multitude of advanced technologies dealing with underground radioactive and hazardous waste remediation. These innovative technologies are being developed as part of integrated comprehensive remediation systems for the effective and efficient remediation of buried waste sites throughout the DOE complex. These efforts are identified and coordinated in support of Environmental Restoration (EM-40) and Waste Management (EM-30) needs and objectives. Sponsored by the DOE Office of Technology Development (EM-50), BWID and LSFA work with universities and private industry to develop technologies that are being transferred to the private sector for use nationally and internationally. This report contains the details of the purpose, logic, and methodology used to develop and demonstrate DOE buried waste remediation technologies. It also provides a catalog of technologies and capabilities with development status for potential users. Past FY-92 through FY-94 technology testing, field trials, and demonstrations are summarized. Continuing and new FY-95 technology demonstrations also are described.

  5. Continuum soil modeling in the static analysis of buried structures

    International Nuclear Information System (INIS)

    Soil loading traditionally has been modeled as a hydrostatic pressure, a practice acceptable for many design applications. In the analysis of buried structures with predictive goals, soil compliance and load redistribution in the presence of soil plasticity are important factors to consider in determining the appropriate response of the structure. In the analysis of existing buried waste-storage tanks at the U.S. Department of Energy's Hanford Site, three soil-tank interaction modeling considerations are addressed. First, the soil interacts with the tank as the tank expands and contracts during thermal cycles associated with changes in the heat generated by the waste material as a result of additions and subtractions of the waste. Second, the soil transfers loads from the surface to the tank and provides support by resisting radial displacement of the tank haunch. Third, conventional finite-element mesh development causes artificial stress concentrations in the soil associated with differential settlement. In predicting the response of the buried high-heat single-shell waste-storage tank 241-C-106 to thermal cycling and significant surcharge loading, a Drucker-Prager plasticity model is used to address soil compliance and surcharge load distribution. Triaxial test data from the Hanford Site are used to derive soil model parameters, which are needed to describe the Drucker-Prager constitutive model

  6. A method for the detection of shallow buried objects

    Directory of Open Access Journals (Sweden)

    T. M. McGee

    2000-06-01

    Full Text Available Numerous geophysical techniques have successfully contributed to geotechnical engineering and environmental problems of the shallow subsurface. Geophysical surveys are used to: delineate geologic features, measure in-situ engineering properties, and detect hidden cultural features. Most technologies for the detection of shallow buried objects are electromagnetic methods which measure the contrast in ferrous content, electrical conductivity, or dielectric constant between the object and surrounding soil. Seismic technologies measure the contrast in mechanical properties of the subsurface, however, scaled down versions of conventional seismic methods are not suitable for the detection shallow buried objects. In this paper, we discuss the development of a method based on acoustic to seismic coupling for the detection of shallow buried object. Surface vibrations induced by an impinging acoustic wave from a loudspeaker is referred to as acoustic to seismic coupling. These vibrations can be remotely detected using a laser-Doppler vibrometer (LDV. If an object is present below the surface of the insonified patch, the transmitted wave is back scattered by the target towards the surface. For targets very close to the surface, the scattered field produces anomalous ground vibrational velocities that are indicative of the shape and size of the target.

  7. The low-frequency noise characteristics of p-type metal-oxide-semiconductor field effect transistors with a strained-Si0.88Ge0.12 channel grown on bulk Si and a PD-SOI substrate

    International Nuclear Information System (INIS)

    Low-frequency noise properties have been investigated for SiGe p-type metal-oxide- semiconductor field effect transistors with different substrates using Si bulk and a partially depleted silicon-on-insulator (PD SOI). The electrical properties of SiGe PD SOI were enhanced in the subthreshold slope and drain induced barrier lowering. However, the low-frequency noise for the PD SOI was found to degrade significantly in terms of the power spectral density. The low frequency noise was observed to follow the typical 1/fγ(γ = 1) dependence in SiGe bulk devices, but abnormal changes with γ = 2 were revealed in the SiGe PD SOI. The difference of the noise frequency exponent was mainly attributed to generation–recombination by traps presented at the silicon–oxide interface of the SOI. Regardless of the degraded noise performance in the SOI structure, the low-frequency noise level remained well at an acceptable level by virtue of the effective carrier confinement in the SiGe channel

  8. The thermal regime around buried submarine high-voltage cables

    Science.gov (United States)

    Emeana, C. J.; Hughes, T. J.; Dix, J. K.; Gernon, T. M.; Henstock, T. J.; Thompson, C. E. L.; Pilgrim, J. A.

    2016-08-01

    The expansion of offshore renewable energy infrastructure and the need for trans-continental shelf power transmission require the use of submarine high-voltage (HV) cables. These cables have maximum operating surface temperatures of up to 70 °C and are typically buried 1-2 m beneath the seabed, within the wide range of substrates found on the continental shelf. However, the heat flow pattern and potential effects on the sedimentary environments around such anomalously high heat sources in the near-surface sediments are poorly understood. We present temperature measurements from a 2-D laboratory experiment representing a buried submarine HV cable, and identify the thermal regimes generated within typical unconsolidated shelf sediments-coarse silt, fine sand and very coarse sand. We used a large (2 × 2.5 m2) tank filled with water-saturated spherical glass beads (ballotini) and instrumented with a buried heat source and 120 thermocouples to measure the time-dependent 2-D temperature distributions. The observed and corresponding Finite Element Method simulations of the steady state heat flow regimes and normalized radial temperature distributions were assessed. Our results show that the heat transfer and thus temperature fields generated from submarine HV cables buried within a range of sediments are highly variable. Coarse silts are shown to be purely conductive, producing temperature increases of >10 °C up to 40 cm from the source of 60 °C above ambient; fine sands demonstrate a transition from conductive to convective heat transfer between cf. 20 and 36 °C above ambient, with >10 °C heat increases occurring over a metre from the source of 55 °C above ambient; and very coarse sands exhibit dominantly convective heat transfer even at very low (cf. 7 °C) operating temperatures and reaching temperatures of up to 18 °C above ambient at a metre from the source at surface temperatures of only 18 °C. These findings are important for the surrounding near

  9. The thermal regime around buried submarine high voltage cables

    Science.gov (United States)

    Emeana, C. J.; Hughes, T. J.; Dix, J. K.; Gernon, T. M.; Henstock, T. J.; Thompson, C. E. L.; Pilgrim, J. A.

    2016-05-01

    The expansion of offshore renewable energy infrastructure and the need for trans-continental shelf power transmission require the use of submarine High Voltage (HV) cables. These cables have maximum operating surface temperatures of up to 70°C and are typically buried 1-2 m beneath the seabed, within the wide range of substrates found on the continental shelf. However, the heat flow pattern and potential effects on the sedimentary environments around such anomalously high heat sources in the near surface sediments are poorly understood. We present temperature measurements from a 2D laboratory experiment representing a buried submarine HV cable, and identify the thermal regimes generated within typical unconsolidated shelf sediments-coarse silt, fine sand and very coarse sand. We used a large (2 × 2.5 m) tank filled with water-saturated spherical glass beads (ballotini) and instrumented with a buried heat source and 120 thermocouples, to measure the time-dependent 2D temperature distributions. The observed and corresponding Finite Element Method (FEM) simulations of the steady state heat flow regimes, and normalised radial temperature distributions were assessed. Our results show that the heat transfer and thus temperature fields generated from submarine HV cables buried within a range of sediments are highly variable. Coarse silts are shown to be purely conductive, producing temperature increases of >10°C up to 40 cm from the source of 60°C above ambient; fine sands demonstrate a transition from conductive to convective heat transfer between c. 20°C and 36°C above ambient, with >10°C heat increases occurring over a metre from the source of 55°C above ambient; and very coarse sands exhibit dominantly convective heat transfer even at very low (c. 7°C) operating temperatures and reaching temperatures of up to 18°C above ambient at a metre from the source at surface temperatures of only 18°C. These findings are important for the surrounding near surface

  10. Laser grooved buried contact cells optimised for linear concentration systems

    Energy Technology Data Exchange (ETDEWEB)

    Vivar, M.; Anton, I.; Sala, G. [Instituto de Energia Solar, UPM, Ciudad Universitaria S/N, 28040 Madrid (Spain); Morilla, C.; Fernandez, J.M. [BP Solar Espana, Pol. Ind. Tres Cantos, s/n Zona Oeste, 28760 Tres Cantos, Madrid (Spain)

    2010-02-15

    Laser grooved buried contact silicon solar cells can be optimised for use in linear concentration systems at low cost. Optimising the groove depth, the copper thickness and the finger pitch by using the Design of Experiments (DOE) experimental methodology can lead to a dramatic reduction of the cell series resistance. This type of cell can be optimised for each application in an industrial line with few changes. For the EUCLIDES III linear concentrator system, optimised cell efficiency metrics for 51 x 116 mm units are in the range of 18-19% at the 40 x concentration level. (author)

  11. Defensive burying in rodents: ethology, neurobiology and psychopharmacology.

    Science.gov (United States)

    De Boer, Sietse F; Koolhaas, Jaap M

    2003-02-28

    Defensive burying refers to the typical rodent behavior of displacing bedding material with vigorous treading-like movements of their forepaws and shoveling movements of their heads directed towards a variety of noxious stimuli that pose a near and immediate threat, such as a wall-mounted electrified shock-prod. Since its introduction 25 years ago by Pinel and Treit [J. Comp. Physiol. Psychol. 92 (1978) 708], defensive (shock-prod) burying has been the focus of a considerable amount of research effort delineating the methodology/ethology, psychopharmacology and neurobiology of this robust and species-specific active avoidance or coping response. The present review gives a summary of this research with special reference to the behavioral (face and construct) and pharmacological (predictive) validity of the shock-prod burying test as an animal model for human anxiety. Emphasis is also placed on some recent modifications of the paradigm that may increase its utility and reliability as to individual differences in expressed emotional coping responses and sensitivity to pharmacological treatments. Overall, the behavioral and physiological responses displayed in the shock-prod paradigm are expressions of normal and functionally adaptive coping patterns and the extremes of either active (i.e., burying) or passive (i.e., freezing) forms of responding in this test cannot simply be regarded as inappropriate, maladaptive or pathological. For this reason, the shock-prod paradigm is not an animal model for anxiety disorder or for any other psychiatric disease, but instead possesses a high degree of face and construct validity for normal and functionally adaptive human fear and anxious apprehension. However, the apparent good pharmacological validation (predictive validity) of this test reinforces the view that normal and pathological anxiety involves, at least partly, common neurobiological substrates. Therefore, this paradigm is not only suitable for screening potential

  12. Remote Excavation System technology evaluation report: Buried Waste Robotics Program

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This document describes the results from the Remote Excavation System demonstration and testing conducted at the Idaho National Engineering Laboratory during June and July 1993. The purpose of the demonstration was to ascertain the feasibility of the system for skimming soil and removing various types of buried waste in a safe manner and within all regulatory requirements, and to compare the performances of manual and remote operation of a backhoe. The procedures and goals of the demonstration were previously defined in The Remote Excavation System Test Plan, which served as a guideline for evaluating the various components of the system and discussed the procedures used to conduct the tests.

  13. Remote Excavation System technology evaluation report: Buried Waste Robotics Program

    International Nuclear Information System (INIS)

    This document describes the results from the Remote Excavation System demonstration and testing conducted at the Idaho National Engineering Laboratory during June and July 1993. The purpose of the demonstration was to ascertain the feasibility of the system for skimming soil and removing various types of buried waste in a safe manner and within all regulatory requirements, and to compare the performances of manual and remote operation of a backhoe. The procedures and goals of the demonstration were previously defined in The Remote Excavation System Test Plan, which served as a guideline for evaluating the various components of the system and discussed the procedures used to conduct the tests

  14. Quantitative Chemically-Specific Coherent Diffractive Imaging of Buried Interfaces using a Tabletop EUV Nanoscope

    OpenAIRE

    Shanblatt, Elisabeth R.; Porter, Christina L.; Gardner, Dennis F.; Mancini, Giulia F.; Karl Jr., Robert M.; Tanksalvala, Michael D.; Bevis, Charles S.; Vartanian, Victor H.; Kapteyn, Henry C.; Adams, Daniel E.; Murnane, Margaret M.

    2016-01-01

    Characterizing buried layers and interfaces is critical for a host of applications in nanoscience and nano-manufacturing. Here we demonstrate non-invasive, non-destructive imaging of buried interfaces using a tabletop, extreme ultraviolet (EUV), coherent diffractive imaging (CDI) nanoscope. Copper nanostructures inlaid in SiO2 are coated with 100 nm of aluminum, which is opaque to visible light and thick enough that neither optical microscopy nor atomic force microscopy can image the buried i...

  15. Imaging of buried phosphorus nanostructures in silicon using scanning tunneling microscopy

    OpenAIRE

    Oberbeck, L.; Reusch, T. C. G.; Hallam, T.; Schofield, S.R.; Curson, N. J.; Simmons, M. Y.

    2014-01-01

    We demonstrate the locating and imaging of single phosphorus atoms and phosphorus dopant nanostructures, buried beneath the Si(001) surface using scanning tunneling microscopy. The buried dopant nanostructures have been fabricated in a bottom-up approach using scanning tunneling microscope lithography on Si(001). We find that current imaging tunneling spectroscopy is suited to locate and image buried nanostructures at room temperature and with residual surface roughness present. From these st...

  16. Helmet-mounted uncooled FPA camera for buried object detection

    Science.gov (United States)

    Miller, John L.; Duvoisin, Herbert A., III; Wiltsey, George

    1997-08-01

    Software neural nets hosted on a parallel processor can analyze input from an IR imager to evaluate the likelihood of a buried object. However, it is only recently that low weight, staring LWIR sensors have become available in uncooled formats at sensitivities that provide enough information for useful man-portable helmet mounted applications. The images from the IR are presented to a human user through a see-through display after processing and highlighting by a neural net housed in a fanny-pack. This paper describes the phenomenology of buried object detection in the infrared, the neural net based image processing, the helmet mounted IR sensor and the ergonomics of mounting a sensor to head gear. The maturing and commercialization of uncooled focal plane arrays and high density electronics enables lightweight, low cost, small camera packages that can be integrated with hard hats and military helmets. The head gear described has a noise equivalent delta temperature (NEDT) of less than 50 milliKelvin, consumes less than 10 watts and weighs about 1.5 kilograms.

  17. Centrifuge modeling of buried continuous pipelines subjected to normal faulting

    Science.gov (United States)

    Moradi, Majid; Rojhani, Mahdi; Galandarzadeh, Abbas; Takada, Shiro

    2013-03-01

    Seismic ground faulting is the greatest hazard for continuous buried pipelines. Over the years, researchers have attempted to understand pipeline behavior mostly via numerical modeling such as the finite element method. The lack of well-documented field case histories of pipeline failure from seismic ground faulting and the cost and complicated facilities needed for full-scale experimental simulation mean that a centrifuge-based method to determine the behavior of pipelines subjected to faulting is best to verify numerical approaches. This paper presents results from three centrifuge tests designed to investigate continuous buried steel pipeline behavior subjected to normal faulting. The experimental setup and procedure are described and the recorded axial and bending strains induced in a pipeline are presented and compared to those obtained via analytical methods. The influence of factors such as faulting offset, burial depth and pipe diameter on the axial and bending strains of pipes and on ground soil failure and pipeline deformation patterns are also investigated. Finally, the tensile rupture of a pipeline due to normal faulting is investigated.

  18. Aging management and life assessment of buried commodities in nuclear power plants

    International Nuclear Information System (INIS)

    General field survey, inspection and life assessment were performed to establish effective aging management program of buried commodities in nuclear power plant. Basic informations on material characteristics, aging degradation experiences and maintenance history were gathered. Considering their degradation effects on power operation or safety, buried commodities were screened for the aging management priority. Various inspection techniques were applied in field survey and inspection, and their results were incorporated in the life assessment of buried commodities. In the aspect of aging degradation, general status of buried commodities were considered still sound while some revealed local degradation

  19. Lunar Radar Scattering from Near-Surface Buried Crater Ejecta

    Science.gov (United States)

    Thompson, T. W.; Ustinov, E. A.; Heggy, E.

    2009-12-01

    The Apollo 15, 16, and 17 core tubes show that the uppermost few meters of the lunar regolith are interlaced layers of a fine grained powders and blocky crater ejecta. The layers of crater ejecta have dielectric constants in the range of 7-9 while the fine-grained powders has dielectric constant on the order of 2.7. These differences in dielectric constant, in turn, create radar reflections that are both refracted and reflected back through the space-regolith interface. Note that for a dielectric constant of 2.7 for the lunar regolith, radio waves incident on the lunar surface at the angle of 30-degrees from the normal will propagate in the regolith at an angle of 18-degrees. At the limb, radio waves incident on the lunar surface at an angle near 90-degrees from the normal will propagate in the regolith at an angle of about 37-degrees. These angles are within the range where radar backscatter is in the quasi-specular regime. When these buried crater ejecta layers are modeled using Hagfors’ formulation (Hagfors, 1963), echo powers match the behavior observed for average lunar backscatter at centimeter wavelengths for higher (30° to 90°) angles of incidence. In addition, Hagfors et al. (1965) conducted an experiment where the Moon was illuminated at 23-cm wavelength with circular polarization and the differences were observed in orthogonal linear polarizations. Modeling of these observations and assuming again that the buried crater ejecta scatter in a quasi-specular manner, echo differences in horizontal and vertical linear polarizations are in relatively good agreement with the observations. The data from Chandrayaan Mini-RF radar, which operated at S-Band (13cm) wavelength, and the Lunar Reconnaissance Orbiter (LRO) Mini-RF radar, which is operating at S-Band and X-Band (4-cm) wavelengths, provide an opportunity for a new examination of whether radar backscatter from buried crater ejecta behaves like a quasi-specular scatter. These radars reproduce the

  20. Novel Si ion implantation technique for improving the radiation hardness of SOI pseudo-MOS transistor

    International Nuclear Information System (INIS)

    The pseudo-MOS transistor is a quick and effective technique for characterizing the electrical properties of silicon-on-insulator (SOI) wafer. We investigated the total ionizing dose (TID) response of pseudo-MOS transistors fabricated on SOI wafers hardened by single or multiple step Si ion implantation. It is demonstrated that the two Si ion implantation methods can both improve the radiation hardness of SOI wafers owing to the generation of deep electron traps in the buried oxide (BOX). However, the lattice damage of top silicon film caused by the single step implantation compared with the multiple degenerates the electrical properties of transistors, especially for the sub-threshold swing. The high resolution transmission electron microscopy (HRTEM) was used to observe the lattice quality

  1. Increase in the scattering of electric field lines in a new high voltage SOI MESFET

    Science.gov (United States)

    Anvarifard, Mohammad K.

    2016-09-01

    This paper illustrates a new efficient technique to enhance the critical features of a silicon-on-insulator metal-semiconductor field-effect transistor (SOI MESFET) applied in high voltage applications. The structure we proposed utilizes a new method to scatter the electric field lines along the channel region. Realization of two trenches with different materials, which a trench is created in the channel region and the other one is created in the buried oxide, helps the proposed structure to improve the breakdown voltage, driving current, drain-source conductance, minimum noise figure, unilateral power gain and output power density. Exploring the obtained results, the proposed structure has superior electrical performance in comparison to the conventional structure.

  2. Nanogranular SiO2 proton gated silicon layer transistor mimicking biological synapses

    Science.gov (United States)

    Liu, M. J.; Huang, G. S.; Feng, P.; Guo, Q. L.; Shao, F.; Tian, Z. A.; Li, G. J.; Wan, Q.; Mei, Y. F.

    2016-06-01

    Silicon on insulator (SOI)-based transistors gated by nanogranular SiO2 proton conducting electrolytes were fabricated to mimic synapse behaviors. This SOI-based device has both top proton gate and bottom buried oxide gate. Electrical transfer properties of top proton gate show hysteresis curves different from those of bottom gate, and therefore, excitatory post-synaptic current and paired pulse facilitation (PPF) behavior of biological synapses are mimicked. Moreover, we noticed that PPF index can be effectively tuned by the spike interval applied on the top proton gate. Synaptic behaviors and functions, like short-term memory, and its properties are also experimentally demonstrated in our device. Such SOI-based electronic synapses are promising for building neuromorphic systems.

  3. TID Simulation of Advanced CMOS Devices for Space Applications

    Science.gov (United States)

    Sajid, Muhammad

    2016-07-01

    This paper focuses on Total Ionizing Dose (TID) effects caused by accumulation of charges at silicon dioxide, substrate/silicon dioxide interface, Shallow Trench Isolation (STI) for scaled CMOS bulk devices as well as at Buried Oxide (BOX) layer in devices based on Silicon-On-Insulator (SOI) technology to be operated in space radiation environment. The radiation induced leakage current and corresponding density/concentration electrons in leakage current path was presented/depicted for 180nm, 130nm and 65nm NMOS, PMOS transistors based on CMOS bulk as well as SOI process technologies on-board LEO and GEO satellites. On the basis of simulation results, the TID robustness analysis for advanced deep sub-micron technologies was accomplished up to 500 Krad. The correlation between the impact of technology scaling and magnitude of leakage current with corresponding total dose was established utilizing Visual TCAD Genius program.

  4. A triple-layer protection process for high-aspect-ratio silicon micromachining by DRIE of SOI substrates

    International Nuclear Information System (INIS)

    Using the buried oxide layer of silicon-on-insulator (SOI) wafers as the etch-stop layer, a triple-layer protection process integrating deep reaction ion etching (DRIE) and wet anisotropic bulk micromachining is demonstrated to fabricate various three-dimensional MEMS devices on SOI wafer. Several limitations of the DRIE process, including bottom grass formation, reactive ion etching lag and notching effects, are solved by modifying the process parameters to achieve satisfactory performance. This process is capable of various applications and is applied to fabricate a resonant pressure sensor in this study. In summary, the developed process possesses most existing merits and reduces many design constraints of the existing high-aspect-ratio micromachining process, contributing to a more competitive and convenient micromachining. (paper)

  5. Baseline tests for arc melter vitrification of INEL buried wastes. Volume 1: Facility description and summary data report

    Energy Technology Data Exchange (ETDEWEB)

    Oden, L.L.; O`Connor, W.K.; Turner, P.C.; Soelberg, N.R.; Anderson, G.L.

    1993-11-19

    This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc melting furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.

  6. Baseline tests for arc melter vitrification of INEL buried wastes. Volume 1: Facility description and summary data report

    International Nuclear Information System (INIS)

    This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc melting furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests

  7. Bryophytes of beach forests in Chon Buri Province, Thailand

    Directory of Open Access Journals (Sweden)

    Phiangphak Sukkharak

    2014-10-01

    Full Text Available An investigation of bryophyte diversity of three beach forests including Had Tung Prong, Had Tein Talay, and the beach forest in Thai Island and Sea Natural History Museum in Chon Buri Province, Thailand, was carried out. From 137 enumerated specimens, 16 species (6 mosses, 10 liverworts in 12 genera (5 mosses, 7 liverworts and eight families (5 mosses, 3 liverworts were found. Among those the most common families of mosses are Fissidentaceae (2 species and the most common families of liverwort are Lejeuneaceae (8 species. A comparison of species richness among the three areas revealed that the highest species richness of bryophytes was found in Had Tung Prong. Moreover, of all bryophyte species found, Weissia edentula Mitt. was the most common one.

  8. Measure Guideline: Buried and/or Encapsulated Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Zoeller, W. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Mantha, P. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2013-08-01

    Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. Some of the procedures presented here, however, require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license.

  9. A Natural Seismic Isolating System: The Buried Mangrove Effects

    CERN Document Server

    Gueguen, Philippe; Foray, Pierre; Rousseau, Christophe; Maury, Julie; 10.1785/0120100129

    2011-01-01

    The Belleplaine test site, located in the island of Guadeloupe (French Lesser Antilles) includes a three-accelerometer vertical array, designed for liquefac- tion studies. The seismic response of the soil column at the test site is computed using three methods: the spectral ratio method using the vertical array data, a numerical method using the geotechnical properties of the soil column, and an operative fre- quency domain decomposition (FDD) modal analysis method. The Belleplaine test site is characterized by a mangrove layer overlaid by a stiff sandy deposit. This con- figuration is widely found at the border coast of the Caribbean region, which is exposed to high seismic hazard. We show that the buried mangrove layer plays the role of an isolation system equivalent to those usually employed in earthquake engineering aimed at reducing the seismic shear forces by reducing the internal stress within the structure. In our case, the flexibility of the mangrove layer reduces the distortion and the stress in the...

  10. Retrieval of Shape Characteristics for Buried Objects with GPR Monitoring

    Science.gov (United States)

    Soldovieri, F.; Comite, D.; Galli, A.; Valerio, G.; Barone, P. M.; Lauro, S. E.; Mattei, E.; Pettinelli, E.

    2012-04-01

    Information retrieval on the location and the geometrical features (dimensions and shape) of buried objects is of fundamental importance in geosciences areas involving environmental protection, mine clearance, archaeological investigations, space and planetary exploration, and so forth. Among the different non-invasive sensing techniques usually employed to achieve this kind of information, those based on ground-penetrating-radar (GPR) instruments are well-established and suitable to the mentioned purposes [1]. In this context, our interest in the present work is specifically focused on testing the potential performance of typical GPR instruments by means of appropriate data processing. It will be shown in particular to what extent the use of a suitable "microwave tomographic approach" [2] is able to furnish a shape estimation of the targets, possibly recognizing different kinds of canonical geometries, even having reduced cross sections and in critical conditions, where the scatterer size is comparable with resolution limits imposed by the usual measurement configurations. Our study starts by obtaining the typical "direct" information from the GPR techniques that is the scattered field in subsurface environments under the form of radargrams. In order to get a wide variety of scenarios for the operating conditions, this goal is achieved by means of two different and independent approaches [3]. One approach is based on direct measurements through an experimental laboratory setup: commercial GPR instruments (typically bistatic configurations operating around 1 GHz frequency range) are used to collect radargram profiles by investigating an artificial basin filled of liquid and/or granular materials (sand, etc.), in which targets (having different constitutive parameters, shape, and dimensions) can be buried. The other approach is based on numerical GPR simulations by means of a commercial CAD electromagnetic tool (CST), whose suitable implementation and data

  11. SEISMIC BEHAVIOR OF BURIED PIPELINES SUBJECTED TO NORMAL FAULT MOTION

    Directory of Open Access Journals (Sweden)

    Seyyed Ali Sabet

    2016-06-01

    Full Text Available The one of the critical elements in infrastructure of today's modern cities that cover large geographic distances is Network of buried pipelines. That is why they face a variety of natural hazards due to permanent ground replacements or wave emissions. Reports suggest that the main cause of damage to these lines is not seismic vibrations but large and permanent ground deformations are major causes of infrastructures' demolition. Most recent studies are related to lines crossing the strike-slip faults, and only a few researchers have tried to study the behavior of structures against the normal fault. This article discusses the behavior and response of structures and infrastructures against the movements of normal faults using the finite elements method. In this study, the interaction between soil-soil and soil-pipe has been considered in modeling terms.

  12. Helium emanometry as an indicator of deeply buried uranium deposits

    International Nuclear Information System (INIS)

    Helium emanometry has considerable potential for locating deeply buried uranium deposits. In order to determine whether near surface helium-4 anomalies are present over and in close proximity to deeply buried uranium deposits, helium measurements were carried out at three sites having known uranium ore bodies: the Red Desert in Sweetwater County, Wyoming; Copper Mountain in Fremont County, Wyoming; and Spokane Mountain in Stevens Couty, Washington. At each research site, near surface soil and soil gas (probe) samples were collected. Borehole water and soil gas (collector) samples were also taken at selected locations. The samples were analyzed at the laboratory for their helium, light hydrocarbon, and nitrogen content. In most instances it was not necessary to correct the soil gas data. In determining the quantity of helium-4 present in the soil gas samples, the practical precision was +- 50 ppb. The reproducibility of the helium-4 analyses of the water samples varied from +- 5% to +- 20%. The total error in the calculated soil helium-4 levels ranged from 5% to 10% of the value. The calculated corrected soil, water and oil gas helium-4 results were analyzed employing statistical techniques in order to separate the background and anomalous populations. The anomalous population was divided into five subsets for purposes of data presentation. The data are then presented in the form of histograms, dot maps and anomaly contour density maps.One can conclude that the results from this study confirm that near surface helium anomalies are present in the gas of the soil micropores overlying three types of uranium deposits situated in widely differing geological environments. The data obtained from the soil gas (probe) helium samples are also encouraging in that anomalies were found to be present over portions of the known extent of each of the three deposits

  13. Numerical Modeling of Mechanical Behavior for Buried Steel Pipelines Crossing Subsidence Strata

    Science.gov (United States)

    Han, C. J.

    2015-01-01

    This paper addresses the mechanical behavior of buried steel pipeline crossing subsidence strata. The investigation is based on numerical simulation of the nonlinear response of the pipeline-soil system through finite element method, considering large strain and displacement, inelastic material behavior of buried pipeline and the surrounding soil, as well as contact and friction on the pipeline-soil interface. Effects of key parameters on the mechanical behavior of buried pipeline were investigated, such as strata subsidence, diameter-thickness ratio, buried depth, internal pressure, friction coefficient and soil properties. The results show that the maximum strain appears on the outer transition subsidence section of the pipeline, and its cross section is concave shaped. With the increasing of strata subsidence and diameter-thickness ratio, the out of roundness, longitudinal strain and equivalent plastic strain increase gradually. With the buried depth increasing, the deflection, out of roundness and strain of the pipeline decrease. Internal pressure and friction coefficient have little effect on the deflection of buried pipeline. Out of roundness is reduced and the strain is increased gradually with the increasing of internal pressure. The physical properties of soil have a great influence on the mechanical properties of buried pipeline. The results from the present study can be used for the development of optimization design and preventive maintenance for buried steel pipelines. PMID:26103460

  14. Image restoration techniques using Compton backscatter imaging for the detection of buried land mines

    Science.gov (United States)

    Wehlburg, Joseph C.; Keshavmurthy, Shyam P.; Watanabe, Yoichi; Dugan, Edward T.; Jacobs, Alan M.

    1995-06-01

    Earlier landmine imaging systems used two collimated detectors to image objects. These systems had difficulty in distinguishing between surface features and buried features. Using a combination of collimated and uncollimated detectors in a Compton backscatter imaging (CBI) system, allows the identification of surface and buried features. Images created from the collimated detectors contain information about the surface and the buried features, while the uncollimated detectors respond (approximately 80%) to features on the surface. The analysis of surface features are performed first, then these features can be removed and the buried features can be identified. Separation of the surface and buried features permits the use of a globbing algorithm to define regions of interest that can then be quantified [area, Y dimension, X dimension, and center location (xo, yo)]. Mine composition analysis is also possible because of the properties of the four detector system. Distinguishing between a pothole and a mine, that was previously very difficult, can now be easily accomplished.

  15. Contribution to classification of buried objects based on acoustic impedance matching.

    Science.gov (United States)

    Stepanić, J; Wüstenberg, H; Krstelj, V; Mrasek, H

    2003-03-01

    Determination of material the buried objects are made of could contribute significantly to their recognition, or classification. This is important in detecting buried antipersonnel landmines within the context of humanitarian demining, as well as in a variety of other applications. In this article the concept has been formulated of the approach to buried object's material determination starting with ultrasonic impulse propagation analysis in a particular testing set configuration. The impulse propagates through a characterized transfer material in such a way that a part of it, a reflected wave, carries the information about the buried object's surface material acoustic impedance. The limit of resolution capability is theoretically analyzed and experimentally evaluated and the influencing factors described. Among these, the contact between clean surfaces of the transfer material and buried object is emphasized. PMID:12565075

  16. The effect of immersion time on burying depth of the bivalve Macoma balthica (Tellinidae)

    Science.gov (United States)

    de Goeij, Petra; Honkoop, Pieter J. C.

    2002-03-01

    As a characteristic buried tellinid bivalve, Macoma balthica has a long inhalent siphon that enables it to feed in two different ways: deposit and suspension feeding. To deposit feed efficiently on benthic microalgae, Macoma has to live close to the sediment surface, where it can graze an extensive surface area, but is within reach of many predators. Individuals that are more safely buried at a greater depth can only suspension feed, or deposit feed from a small surface area. We expected local differences in burying depth on intertidal mudflats to be caused by differences in immersion time (i.e. time available for feeding, particularly suspension feeding), since immersion time has been shown experimentally to affect body condition positively, and since body condition and burying depth in Macoma are postively related in the field. To test this we experimentally manipulated immersion time, and followed changes in burying depth and body condition. In the experiments, longer immersion time went consistently with greater burying depth of Macoma and higher body condition. On a transect in the western Wadden Sea, the deepest Macoma were indeed found at the intertidal level with the longest immersion time, but these were at that time not the animals with the highest body condition. Within each locality, however, body condition was positively correlated with burying depth. The experimental data and the within-locality data support the hypothesis that longer immersion time may influence burying depth through body condition. However, the fact that between-locality differences in burying depth seemed to be consistently related to immersion time, but not to body condition, indicates that body condition alone does not explain place-to-place variation in burying depth.

  17. Microbially influenced corrosion of buried pipelines and its control; Dojo maisetsu pipeline no biseibutsu fushoku to sono taisaku

    Energy Technology Data Exchange (ETDEWEB)

    Kajiyama, F. [Tokyo Gas Co. Ltd., Tokyo (Japan)

    1997-08-25

    This paper describes microbially influenced corrosion (MIC) on buried pipelines and its preventive measures. Major microorganisms involved in the corrosion include iron bacteria, iron oxidized bacteria, sulfur oxidized bacteria, sulfate reduced bacteria, and methane producing bacteria, which are largely divided into aerobic and anaerobic bacteria. There is high negative correlation between oxidation-reduction potential `E{sub h}` and pH of soils, and activity regions of each microorganism correspond to each region determined by E{sub h} - pH. According to the result of experimentally measuring the MIC rate in cast iron pipes, the rate was found to decrease in the order of iron bacteria > iron oxidized bacteria > sulfate reduced bacteria. As a first measure to prevent MIC, it is necessary to isolate pipes from soil. The present study disclosed that it is absolutely necessary to apply a coating having high insulation performance and take measures of cathodic protection, and that the corrosion may be prevented if the conventionally recommended anti-corrosive potential is cleared and electric current is flowing into defective parts even if a defect has occurred in the coating. 26 refs., 10 figs., 1 tab.

  18. Geological characteristics in buried coalfields synthetically using remote sensing and non-remote sensing information

    Science.gov (United States)

    Dai, Shifeng; Wang, Silong; Liu, Yurong

    1998-08-01

    With the rapid development of coal industry in China, the emphasis of the geological exploration has been changed from the exposed area to the buried area. Because of the limitation of the geological condition and the exploration methods, it is very difficult to study the geological phenomena in buried coalfield. To the coal geologists in China, to search an effective and practical method has been the important tackle key problem for recent years. In this paper, the authors discussed the characteristics of remote sensing technology in the geological study, and the forming mechanism of remote sensing information in the buried area from the view of agrology and physics, so the important academic evidences were offered for the geological study using remote sensing image in the buried coalfield. The characteristics of the non-remote sensing information, the geophysics information and the basal geological information, were also introduced in the study of buried geological bodies. The authors expounded the general processing method in the investigation of buried geological bodies using remote sensing and non-remote sensing information. At last, the probable distribution area of buried igneous rocks, in Huaibei coalfield in China, were successfully forecasted synthetically using the remote sensing, and non-remote sensing information.

  19. Of mice and marbles: Novel perspectives on burying behavior as a screening test for psychiatric illness.

    Science.gov (United States)

    Wolmarans, De Wet; Stein, Dan J; Harvey, Brian H

    2016-06-01

    Burying forms part of the normal behavioral routine of rodents, although its expression is species-specific. However, it has been suggested that aberrant burying behavior, of which marble-burying (MB) is an example, may represent neophobic and/or compulsive-like behavior. In the present investigation, we assessed MB in an established animal model of obsessive-compulsive disorder (OCD)-namely, spontaneous stereotypy in the deer mouse-to establish whether high (H) stereotypy is associated with neophobia and/or another compulsive endophenotype, i.e. MB, as compared to nonstereotypical (N) controls. A three-trial, one-zone MB test was performed over three consecutive evenings both before and after chronic treatment with high-dose (50 mg/kg/day) oral escitalopram. Neophobia was measured via the number of marbles buried during the first pre- and posttreatment MB trials, and compulsive-like behavior via the number of marbles buried over all pre- and posttreatment MB trials. The data from the present study support earlier findings that burying is a normal behavioral routine (inherent burying behavior, IBB) that is expressed by all deer mice, irrespective of stereotypical cohort, and is not associated with either neophobia or compulsiveness. Indeed, chronic escitalopram treatment, which is similarly effective in treating clinical anxiety and OCD, as well as in attenuating H behavior, failed to influence IBB. Although 11 % of the animals presented with a unique burying endophenotype (high burying behavior), escitalopram also failed to attenuate said behavior, necessitating further investigation as to its relevance. In conclusion, MB cannot be regarded as a measure of anxiety-like or compulsive behavior in the deer mouse model of OCD. PMID:26920212

  20. Bedrock mapping of buried valley networks using seismic reflection and airborne electromagnetic data

    Science.gov (United States)

    Oldenborger, G. A.; Logan, C. E.; Hinton, M. J.; Pugin, A. J.-M.; Sapia, V.; Sharpe, D. R.; Russell, H. A. J.

    2016-05-01

    In glaciated terrain, buried valleys often host aquifers that are significant groundwater resources. However, given the range of scales, spatial complexity and depth of burial, buried valleys often remain undetected or insufficiently mapped. Accurate and thorough mapping of bedrock topography is a crucial step in detecting and delineating buried valleys and understanding formative valley processes. We develop a bedrock mapping procedure supported by the combination of seismic reflection data and helicopter time-domain electromagnetic data with water well records for the Spiritwood buried valley aquifer system in Manitoba, Canada. The limited spatial density of water well bedrock observations precludes complete depiction of the buried valley bedrock topography and renders the water well records alone inadequate for accurate hydrogeological model building. Instead, we leverage the complementary strengths of seismic reflection and airborne electromagnetic data for accurate local detection of the sediment-bedrock interface and for spatially extensive coverage, respectively. Seismic reflection data are used to define buried valley morphology in cross-section beneath survey lines distributed over a regional area. A 3D model of electrical conductivity is derived from inversion of the airborne electromagnetic data and used to extrapolate buried valley morphology over the entire survey area. A spatially variable assignment of the electrical conductivity at the bedrock surface is applied to different features of the buried valley morphology identified in the seismic cross-sections. Electrical conductivity is then used to guide construction of buried valley shapes between seismic sections. The 3D locus of points defining each morphological valley feature is constructed using a path optimization routine that utilizes deviation from the assigned electrical conductivities as the cost function. Our resulting map represents a bedrock surface of unprecedented detail with more

  1. Colossal optical transmission through buried metal gratings (Presentation Recording)

    Science.gov (United States)

    Roberts, Christopher M.; Liu, Runyu; Zhao, Xiang; Yu, Lan; Li, Xiuling; Wasserman, Daniel M.; Podolskiy, Viktor A.

    2015-09-01

    In Extraordinary Optical Transmission (EOT), a metallic film perforated with an array of [periodic] apertures exhibits transmission over 100% normalized to the total aperture area, at selected frequencies. EOT devices have potential applications as optical filters and as couplers in hybrid electro-optic contacts/devices. Traditional passive extraordinary optical transmission structures, typically demonstrate un-normalized transmission well below 50%, and are typically outperformed by simpler thin-film techniques. To overcome these limitations, we demonstrate a new breed of extraordinary optical transmission devices, by "burying" an extraordinary optical transmission grating in a dielectric matrix via a metal-assisted-chemical etching process. The resulting structure is an extraordinary optical transmission grating on top of a dielectric substrate with dielectric nano-pillars extruded through the grating apertures. These structures not only show significantly enhanced peak transmission when normalized to the open area of the metal film, but more importantly, peak transmission greater than that observed from the bare semiconductor surface. The structures were modeled using three-dimensional rigorous coupled wave analysis and characterized experimentally by Fourier transform infrared reflection and transmission spectroscopy, and the good agreement between the two has been demonstrated. The drastic enhancement of light transmission in our structures originates from structuring of high-index dielectric substrate, with pillars effectively guiding light through metal apertures.

  2. An Effective Method for Borehole Imaging of Buried Tunnels

    Directory of Open Access Journals (Sweden)

    Loreto Di Donato

    2012-01-01

    Full Text Available Detection and imaging of buried tunnels is a challenging problem which is relevant to both geophysical surveys and security monitoring. To comply with the need of exploring large portions of the underground, electromagnetic measurements carried out under a borehole configuration are usually exploited. Since this requires to drill holes in the soil wherein the transmitting and receiving antennas have to be positioned, low complexity of the involved apparatus is important. On the other hand, to effectively image the surveyed area, there is the need for adopting efficient and reliable imaging methods. To address these issues, in this paper we investigate the feasibility of the linear sampling method (LSM, as this inverse scattering method is capable to provide almost real-time results even when 3D images of very large domains are built, while not requiring approximations of the underlying physics. In particular, the results of the reported numerical analysis show that the LSM is capable of performing the required imaging task while using a quite simple measurement configuration consisting of two boreholes and a few number of multiview-multistatic acquisitions.

  3. In-situ containment and stabilization of buried waste

    International Nuclear Information System (INIS)

    In FY 1993 research continued on development and testing of grout materials for in-situ containment and stabilization of buried waste. Specifically, the work was aimed at remediation of the Chemical Waste Landfill (CWL) at Sandia National Laboratories (SNL) in Albuquerque, New Mexico as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). The work on grouting materials was initiated in FY 1992 and the accomplishments for that year are documented in the previous annual report (Allan, Kukacka and Heiser, 1992). The remediation plan involves stabilization of the chromium plume, placement of impermeable vertical and horizontal barriers to isolate the landfill and installation of a surface cap. The required depth of subsurface barriers is approximately 33 m (100 ft). The work concentrated on optimization of grout formulations for use as grout and soil cement barriers and caps. The durability of such materials was investigated, in addition to shrinkage cracking resistance, compressive and flexural strength and permeability. The potential for using fibers in grouts to control cracking was studied. Small scale field trials were conducted to test the practicality of using the identified formulations and to measure the long term performance. Large scale trials were conducted at Sandia as part of the Subsurface Barrier Emplacement Technology Program. Since it was already determined in FY 1992 that cementitious grouts could effectively stabilize the chromium plume at the CWL after pre-treatment is performed, the majority of the work was devoted to the containment aspect

  4. Measure Guideline: Buried and/or Encapsulated Ducts

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Zoeller, W.; Mantha, P.

    2013-08-01

    Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. This Building America Measure Guideline synthesizes previously published research on BEDs and provides practical information to builders, contractors, homeowners, policy analysts, building professions, and building scientists. Some of the procedures presented here, however, require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license. Persons implementing duct system improvements should not go beyond their expertise or qualifications. This guideline provides valuable information for a building industry that has struggled to address ductwork thermal losses in new and existing homes. As building codes strengthen requirements for duct air sealing and insulation, flexibility is needed to address energy efficiency goals. While ductwork in conditioned spaces has been promoted as the panacea for addressing ductwork thermal losses, BEDs installations approach - and sometimes exceed - the performance of ductwork in conditioned spaces.

  5. The Challenging Buried Bumper Syndrome after Percutaneous Endoscopic Gastrostomy

    Science.gov (United States)

    Afifi, Ibrahim; Zarour, Ahmad; Al-Hassani, Ammar; Peralta, Ruben; El-Menyar, Ayman; Al-Thani, Hassan

    2016-01-01

    Buried bumper syndrome (BBS) is a rare complication developed after percutaneous endoscopic gastrostomy (PEG). We report a case of a 38-year-old male patient who sustained severe traumatic brain injury that was complicated with early BBS after PEG tube insertion. On admission, bedside PEG was performed, and 7 days later the patient developed signs of sepsis with rapid progression to septic shock and acute kidney injury. Abdominal CT scan revealed no collection or leakage of the contrast, but showed malpositioning of the tube bumper at the edge of the stomach and not inside of it. Diagnostic endoscopy revealed that the bumper was hidden in the posterolateral part of the stomach wall forming a tract inside of it, which confirmed the diagnosis of BBS. The patient underwent laparotomy with a repair of the stomach wall perforation, and the early postoperative course was uneventful. Acute BBS is a rare complication of PEG tube insertion which could be manifested with severe complications such as pressure necrosis, peritonitis and septic shock. Early identification is the mainstay to prevent such complications. Treatment selection is primarily guided by the presenting complications, ranging from simple endoscopic replacement to surgical laparotomy. PMID:27462190

  6. The Low Frequency Aeroacoustics of Buried Nozzle Systems

    Science.gov (United States)

    Taylor, M. V.; Crighton, D. G.; Cargill, A. M.

    1993-05-01

    A simplified model of a "buried nozzle" aeroengine system is considered. The primary flow issues into a co-annular flow within a mixing chamber, and then the co-annular flow issues into the ambient medium from a secondary nozzle. Within the mixing chamber only fine scale mixing takes place, and shear layers within the mixing chamber and downstream of the secondary nozzle are assumed to sustain large scale instability waves. Excitation of this system is provided by low frequency plane waves, incident from upstream on the primary nozzle (and emanating from combustion processes in the hot core of an aeroengine). The response of this system, in the acoustic far field and in the mixing chamber, is obtained analytically from the asymptotic solution, at low frequency, of model sub-problems the solutions of which determine the wave reflection and transmission processes at the primary and secondary nozzles. In these sub-problems the shear layers are represented by vortex sheets and the nozzle walls by semi-infinite circular ducts, with Kutta conditions imposed on the unsteady flow at the primary and secondary nozzle lips. Analytical descriptions are given of the various wave modes (quasi-plane acoustic waves, and instability waves localized on the primary and secondary shear layers), of the acoustic field strength and directivity (essentially monopole, dipole and quadrupole fields), and of the conditions under which near-resonant response may occur, with large amplitudes of the perturbations in the mixing chamber and in the acoustic field.

  7. Thermal processing system concepts and considerations for RWMC buried waste

    Energy Technology Data Exchange (ETDEWEB)

    Eddy, T.L.; Kong, P.C.; Raivo, B.D.; Anderson, G.L.

    1992-02-01

    This report presents a preliminary determination of ex situ thermal processing system concepts and related processing considerations for application to remediation of transuranic (TRU)-contaminated buried wastes (TRUW) at the Radioactive Waste Management Complex (RWMC) of the Idaho National Engineering Laboratory (INEL). Beginning with top-level thermal treatment concepts and requirements identified in a previous Preliminary Systems Design Study (SDS), a more detailed consideration of the waste materials thermal processing problem is provided. Anticipated waste stream elements and problem characteristics are identified and considered. Final waste form performance criteria, requirements, and options are examined within the context of providing a high-integrity, low-leachability glass/ceramic, final waste form material. Thermal processing conditions required and capability of key systems components (equipment) to provide these material process conditions are considered. Information from closely related companion study reports on melter technology development needs assessment and INEL Iron-Enriched Basalt (IEB) research are considered. Five potentially practicable thermal process system design configuration concepts are defined and compared. A scenario for thermal processing of a mixed waste and soils stream with essentially no complex presorting and using a series process of incineration and high temperature melting is recommended. Recommendations for applied research and development necessary to further detail and demonstrate the final waste form, required thermal processes, and melter process equipment are provided.

  8. Surface wave propagation effects on buried segmented pipelines

    Directory of Open Access Journals (Sweden)

    Peixin Shi

    2015-08-01

    Full Text Available This paper deals with surface wave propagation (WP effects on buried segmented pipelines. Both simplified analytical model and finite element (FE model are developed for estimating the axial joint pullout movement of jointed concrete cylinder pipelines (JCCPs of which the joints have a brittle tensile failure mode under the surface WP effects. The models account for the effects of peak ground velocity (PGV, WP velocity, predominant period of seismic excitation, shear transfer between soil and pipelines, axial stiffness of pipelines, joint characteristics, and cracking strain of concrete mortar. FE simulation of the JCCP interaction with surface waves recorded during the 1985 Michoacan earthquake results in joint pullout movement, which is consistent with the field observations. The models are expanded to estimate the joint axial pullout movement of cast iron (CI pipelines of which the joints have a ductile tensile failure mode. Simplified analytical equation and FE model are developed for estimating the joint pullout movement of CI pipelines. The joint pullout movement of the CI pipelines is mainly affected by the variability of the joint tensile capacity and accumulates at local weak joints in the pipeline.

  9. Graphite electrode DC arc technology program for buried waste treatment

    International Nuclear Information System (INIS)

    The goal of the program is to apply EPI's Arc Furnace to the processing of Subsurface Disposal Area (SDA) waste from Idaho National Engineering Laboratory. This is being facilitated through the Department of Energy's Buried Waste Integrated Demonstration (BWID) program. A second objective is to apply the diagnostics capability of MIT's Plasma Fusion Center to the understanding of the high temperature processes taking place in the furnace. This diagnostics technology has promise for being applicable in other thermal treatment processes. The program has two parts, a test series in an engineering-scale DC arc furnace which was conducted in an EPI furnace installed at the Plasma Fusion Center and a pilot-scale unit which is under construction at MIT. This pilot-scale furnace will be capable of operating in a continuous feed and continuous tap mode. Included in this work is the development and implementation of diagnostics to evaluate high temperature processes such as DC arc technology. This technology can be used as an effective stabilization process for Superfund wastes

  10. Thermal processing system concepts and considerations for RWMC buried waste

    International Nuclear Information System (INIS)

    This report presents a preliminary determination of ex situ thermal processing system concepts and related processing considerations for application to remediation of transuranic (TRU)-contaminated buried wastes (TRUW) at the Radioactive Waste Management Complex (RWMC) of the Idaho National Engineering Laboratory (INEL). Beginning with top-level thermal treatment concepts and requirements identified in a previous Preliminary Systems Design Study (SDS), a more detailed consideration of the waste materials thermal processing problem is provided. Anticipated waste stream elements and problem characteristics are identified and considered. Final waste form performance criteria, requirements, and options are examined within the context of providing a high-integrity, low-leachability glass/ceramic, final waste form material. Thermal processing conditions required and capability of key systems components (equipment) to provide these material process conditions are considered. Information from closely related companion study reports on melter technology development needs assessment and INEL Iron-Enriched Basalt (IEB) research are considered. Five potentially practicable thermal process system design configuration concepts are defined and compared. A scenario for thermal processing of a mixed waste and soils stream with essentially no complex presorting and using a series process of incineration and high temperature melting is recommended. Recommendations for applied research and development necessary to further detail and demonstrate the final waste form, required thermal processes, and melter process equipment are provided

  11. Detection of Buried Human Remains Using Bioreporter Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Vass, A. Dr.; Singleton, G. B.

    2001-10-01

    The search for buried human remains is a difficult, laborious and time-consuming task for law enforcement agencies. This study was conducted as a proof of principle demonstration to test the concept of using bioreporter microorganisms as a means to cover large areas in such a search. These bioreporter microorganisms are affected by a particular component of decaying organic matter that is distinct from decaying vegetation. The diamino compounds cadaverine and putrescine were selected as target compounds for the proof-of-principle investigation, and a search for microorganisms and genes that are responsive to either of these compounds was conducted. One recombinant clone was singled out for characterization based on its response to putrescine. The study results show that small concentrations of putrescine increased expression from this bioreporter construct. Although the level of increase was small (making it difficult to distinguish the signal from background), the results demonstrate the principle that bioreporters can be used to detect compounds resulting from decaying human remains and suggest that a wider search for target compounds should be conducted.

  12. Detecting buried explosive hazards with handheld GPR and deep learning

    Science.gov (United States)

    Besaw, Lance E.

    2016-05-01

    Buried explosive hazards (BEHs), including traditional landmines and homemade improvised explosives, have proven difficult to detect and defeat during and after conflicts around the world. Despite their various sizes, shapes and construction material, ground penetrating radar (GPR) is an excellent phenomenology for detecting BEHs due to its ability to sense localized differences in electromagnetic properties. Handheld GPR detectors are common equipment for detecting BEHs because of their flexibility (in part due to the human operator) and effectiveness in cluttered environments. With modern digital electronics and positioning systems, handheld GPR sensors can sense and map variation in electromagnetic properties while searching for BEHs. Additionally, large-scale computers have demonstrated an insatiable appetite for ingesting massive datasets and extracting meaningful relationships. This is no more evident than the maturation of deep learning artificial neural networks (ANNs) for image and speech recognition now commonplace in industry and academia. This confluence of sensing, computing and pattern recognition technologies offers great potential to develop automatic target recognition techniques to assist GPR operators searching for BEHs. In this work deep learning ANNs are used to detect BEHs and discriminate them from harmless clutter. We apply these techniques to a multi-antennae, handheld GPR with centimeter-accurate positioning system that was used to collect data over prepared lanes containing a wide range of BEHs. This work demonstrates that deep learning ANNs can automatically extract meaningful information from complex GPR signatures, complementing existing GPR anomaly detection and classification techniques.

  13. Biogeochemistry of pyrite and iron sulfide oxidation in marine sediments

    DEFF Research Database (Denmark)

    Schippers, A.; Jørgensen, BB

    2002-01-01

    Pyrite (FeS2) and iron monosulfide (FeS) play a central role in the sulfur and iron cycles of marine sediments, They may be buried in the sediment or oxidized by O-2 after transport by bioturbation to the sediment surface. FeS2 and FeS may also be oxidized within the anoxic sediment in which NO3-...

  14. Pannus Is the New Prepuce? Penile Cancer in a Buried Phallus

    Directory of Open Access Journals (Sweden)

    Jared Manwaring

    2015-01-01

    Full Text Available Two males presented to our urology department with complaints of bleeding and malodor from buried phallus within a suprapubic fat pad. Although both men had neonatal circumcisions, advanced penile carcinoma was found in both men. Formal penectomies showed high grade, poorly differentiated squamous cell carcinoma invading the corporal bodies and urethra. Buried penis represents a difficulty in early detection of suspicious lesions but may also provide an environment susceptible to poor hygiene and subsequent chronic inflammation. Patients with buried penis may be at a higher risk for development of invasive penile cancer and may benefit from regular and thorough genital exams.

  15. Pannus Is the New Prepuce? Penile Cancer in a Buried Phallus.

    Science.gov (United States)

    Manwaring, Jared; Vourganti, Srinivas; Nikolavsky, Dmitriy; Valente, Alfredo L; Byler, Timothy

    2015-01-01

    Two males presented to our urology department with complaints of bleeding and malodor from buried phallus within a suprapubic fat pad. Although both men had neonatal circumcisions, advanced penile carcinoma was found in both men. Formal penectomies showed high grade, poorly differentiated squamous cell carcinoma invading the corporal bodies and urethra. Buried penis represents a difficulty in early detection of suspicious lesions but may also provide an environment susceptible to poor hygiene and subsequent chronic inflammation. Patients with buried penis may be at a higher risk for development of invasive penile cancer and may benefit from regular and thorough genital exams. PMID:26446361

  16. Imaging of buried phosphorus nanostructures in silicon using scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oberbeck, Lars [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); TOTAL Marketing Services, New Energies, La Défense 10, 92069 Paris La Défense Cedex (France); Reusch, Thilo C. G.; Hallam, Toby; Simmons, Michelle Y., E-mail: n.curson@ucl.ac.uk, E-mail: michelle.simmons@unsw.edu.au [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); Schofield, Steven R. [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); London Centre for Nanotechnology, UCL, London WC1H 0AH (United Kingdom); Department of Physics and Astronomy, UCL, London WC1E 6BT (United Kingdom); Curson, Neil J., E-mail: n.curson@ucl.ac.uk, E-mail: michelle.simmons@unsw.edu.au [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); London Centre for Nanotechnology, UCL, London WC1H 0AH (United Kingdom); Department of Electronic and Electrical Engineering, UCL, London WC1E 7JE (United Kingdom)

    2014-06-23

    We demonstrate the locating and imaging of single phosphorus atoms and phosphorus dopant nanostructures, buried beneath the Si(001) surface using scanning tunneling microscopy. The buried dopant nanostructures have been fabricated in a bottom-up approach using scanning tunneling microscope lithography on Si(001). We find that current imaging tunneling spectroscopy is suited to locate and image buried nanostructures at room temperature and with residual surface roughness present. From these studies, we can place an upper limit on the lateral diffusion during encapsulation with low-temperature Si molecular beam epitaxy.

  17. Imaging of buried phosphorus nanostructures in silicon using scanning tunneling microscopy

    International Nuclear Information System (INIS)

    We demonstrate the locating and imaging of single phosphorus atoms and phosphorus dopant nanostructures, buried beneath the Si(001) surface using scanning tunneling microscopy. The buried dopant nanostructures have been fabricated in a bottom-up approach using scanning tunneling microscope lithography on Si(001). We find that current imaging tunneling spectroscopy is suited to locate and image buried nanostructures at room temperature and with residual surface roughness present. From these studies, we can place an upper limit on the lateral diffusion during encapsulation with low-temperature Si molecular beam epitaxy.

  18. An integrated systems approach to remote retrieval of buried transuranic waste using a telerobotic transport vehicle, innovative end effector, and remote excavator

    International Nuclear Information System (INIS)

    Between 1952 and 1970, over two million cubic feet of transuranic mixed waste was buried in shallow pits and trenches in the Subsurface Disposal Area at the Idaho National Engineering Laboratory Radioactive Waste Management Complex. Commingled with this two million cubic feet of waste is up to 10 million cubic feet of fill soil. The pits and trenches were constructed similarly to municipal landfills with both stacked and random dump waste forms such as barrels and boxes. The main contaminants are micron-sized particles of plutonium and americium oxides, chlorides, and hydroxides. Retrieval, treatment, and disposal is one of the options being considered for the waste. This report describes the results of a field demonstration conducted to evaluate technologies for excavating, and transporting buried transuranic wastes at the INEL, and other hazardous or radioactive waste sites throughout the US Department of Energy complex. The full-scale demonstration, conduced at RAHCO Internationals facilities in Spokane, Washington, in the summer of 1994, evaluated equipment performance and techniques for digging, dumping, and transporting buried waste. Three technologies were evaluated in the demonstration: an Innovative End Effector for dust free dumping, a Telerobotic Transport Vehicle to convey retrieved waste from the digface, and a Remote Operated Excavator to deploy the Innovative End Effector and perform waste retrieval operations. Data were gathered and analyzed to evaluate retrieval performance parameters such as retrieval rates, transportation rates, human factors, and the equipment's capability to control contamination spread

  19. An integrated systems approach to remote retrieval of buried transuranic waste using a telerobotic transport vehicle, innovative end effector, and remote excavator

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.M.; Rice, P.; Hyde, R. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States); Peterson, R. [RAHCO International, Spokane, WA (United States)

    1995-02-01

    Between 1952 and 1970, over two million cubic feet of transuranic mixed waste was buried in shallow pits and trenches in the Subsurface Disposal Area at the Idaho National Engineering Laboratory Radioactive Waste Management Complex. Commingled with this two million cubic feet of waste is up to 10 million cubic feet of fill soil. The pits and trenches were constructed similarly to municipal landfills with both stacked and random dump waste forms such as barrels and boxes. The main contaminants are micron-sized particles of plutonium and americium oxides, chlorides, and hydroxides. Retrieval, treatment, and disposal is one of the options being considered for the waste. This report describes the results of a field demonstration conducted to evaluate technologies for excavating, and transporting buried transuranic wastes at the INEL, and other hazardous or radioactive waste sites throughout the US Department of Energy complex. The full-scale demonstration, conduced at RAHCO Internationals facilities in Spokane, Washington, in the summer of 1994, evaluated equipment performance and techniques for digging, dumping, and transporting buried waste. Three technologies were evaluated in the demonstration: an Innovative End Effector for dust free dumping, a Telerobotic Transport Vehicle to convey retrieved waste from the digface, and a Remote Operated Excavator to deploy the Innovative End Effector and perform waste retrieval operations. Data were gathered and analyzed to evaluate retrieval performance parameters such as retrieval rates, transportation rates, human factors, and the equipment`s capability to control contamination spread.

  20. Solvent exchange of buried water and hydrogen exchange of peptide NH groups hydrogen bonded to buried waters in bovine pancreatic trypsin inhibitor

    International Nuclear Information System (INIS)

    Solvent exchange of 18O-labeled buried water in bovine pancreatic trypsin inhibitor (BPTI), trypsin, and trypsin-BPTI complex is measured by high-precision isotope ratio mass spectroscopy. Buried water is labeled by equilibrium of the protein in 18O-enriched water. Protein samples are then rapidly dialyzed against water of normal isotope composition by gel filtration and stored. The exchangeable 18O label eluting with the protein in 10-300 s is determined by an H2O-CO2 equilibration technique. Exchange of buried waters with solvent water is complete before 10-15 s in BPTI, trypsin, and BPTI-trypsin, as well as in lysozyme and carboxypeptidase measured as controls. When in-exchange dialysis and storage are carried out at pH ≥ 2.5, trypsin-BPTI and trypsin, but not free BPTI, have the equivalent of one 18O atom that exchanges slowly (after 300 s and before several days). This oxygen is probably covalently bound to a specific site in trypsin. When in-exchange dialysis and storage are carried out at pH 1.1, the equivalent of three to seven 18O atoms per molecule is associated with the trypsin-BPTI complex, apparently due to nonspecific covalent 18O labeling of carboxyl groups at low pH. In addition to 18O exchange of buried waters, the hydrogen isotope exchange of buried NH groups H bonded to buried waters was also measured. Their base-catalyzed exchange rate constants are on the order of NH groups that in the crystal are exposed to solvent and hydrogen-bonded main chain O, and their pH/sub min/ is similar to that for model compounds. The pH dependence of their exchange rate constants suggests that direct exchange with water may significantly contribute to their observed exchange rate

  1. [Super-low-frequency spectrum analysis for buried faults in coalfield].

    Science.gov (United States)

    Chen, Li; Qin, Qi-Ming; Zhen, Guang-Wei; Wang, Nan; Bai, Yan-Bing; Chen, Chao

    2013-08-01

    Based on the super-low-frequency (SLF) electromagnetic detection technology, the advanced detection for the buried fault in the coalfield is still at the exploratory stage, while the technology has a strong practical significance for production and design of the coal mine. Firstly, in this paper, the SLF electromagnetic detection signals were collected in study area. Spectrum analysis of SLF signal by wavelet transform can remove high-frequency noise. Secondly, the profile of the measuring line across the fault was analyzed and interpreted geologically. Accordingly SLF spectrum characteristics of the buried fault could be researched. Finally, combined with the geological and seismic data, the characteristics and distribution of fault structures can be verified in the mining area. The results show that: the buried fault could be detected quickly and effectively by SLF electromagnetic detection Hence, SLF electromagnetic detection technology is an effective method for buried fault detection. PMID:24159862

  2. Buried planar and channel waveguides in sapphire and Ti:sapphire by proton implantation

    NARCIS (Netherlands)

    Laversenne, L.; Hoffmann, P.; Pollnau, M.; Moretti, P.

    2004-01-01

    Buried, stacked planar and channel waveguides in sapphire and Ti:sapphire are fabricated by proton implantation. Flexibility of the fabrication technique and good control over the implantation parameters result in variable design and excellent light confinement.

  3. Buried planar and channel waveguides in sapphire and Ti:sapphire by proton implantation

    NARCIS (Netherlands)

    Laversenne, Laetitia; Hoffmann, Patrik; Pollnau, Markus; Moretti, Paul

    2004-01-01

    Buried, stacked planar, and channel waveguides fabricated by proton implantation into sapphire are demonstrated for the first time. The good control of implantation parameters is promising to achieve active integrated optics devices Ti3+:sapphire.

  4. Potential of bioremediation for buried oil removal in beaches after an oil spill.

    Science.gov (United States)

    Pontes, Joana; Mucha, Ana P; Santos, Hugo; Reis, Izabela; Bordalo, Adriano; Basto, M Clara; Bernabeu, Ana; Almeida, C Marisa R

    2013-11-15

    Bioremediation potential for buried oil removal, an application still lacking thorough research, was assessed in a specifically designed system in which an artificially contaminated oil layer of sand was buried in a sand column subjected to tidal simulation. The efficiency of biostimulation (BS, fertilizer addition) and bioaugmentation (BA, inoculation of pre-stimulated indigenous hydrocarbon-degrading microorganisms plus fertilizer) compared to natural attenuation was tested during a 180-day experimental period. The effect of BA was evident after 60 days (degradation of hydrocarbons reached 80%). BS efficacy was revealed only after 120 days. Microorganisms and nutrients added at the top of the sand column were able to reach the buried oil layer and contributed to faster oil elimination, an important feature for effective bioremediation treatments. Therefore, autochthonous BA with suitable nutritive conditions results in faster oil-biodegradation, appears to be a cost-effective methodology for buried oil remediation and contributes to the recovery of oil-impacted areas. PMID:24054785

  5. Spatial and spectral oxide trap distributions of power MOSFETs

    International Nuclear Information System (INIS)

    Commercial power MOSFET (A, B and C) oxides have been characterized by irradiation and isochronal annealing. Low dose irradiation (100 krad(SiO2) under positive and negative bias shows a uniform oxide charge trapping for the two unhardened devices and an interfacial oxide trap distribution in the case of the rad-hard device. High dose irradiation (10 Mrad(SiO2) under high negative bias demonstrates the build-up of an electron trapped charge for device A and the conduction at high dose of a parasitic transistor for device B. Irradiation up to 100 krad(SiO2) and isochronal annealing under positive bias is carried out to compare the spectral distribution of oxide traps between device A oxide and reference buried oxides (SIMOX and UNIBOND). Despite a similar trapping behavior, their spectral distributions are different. Device A presents a lower energy distribution than buried oxides. (authors)

  6. Methanogenic degradation of rice plant buried in paddy soil

    International Nuclear Information System (INIS)

    We investigated the degradation of three fractions of matured rice plant (stem, leaf and root) in paddy soil. To determine the loss of weights of these fractions due to degradation, 0.5 g of each fraction were sealed in a nylon bag (mesh size 25μm) and buried in a glass bottle containing a mixture of 800 g soil and 260 ml water. The losses of dry weight of stem and leaf were 60% and 50%, respectively, after incubation at 30degC for 110 days. Root was the most refractory to degradation, showing only 25% loss of dry weight. For the determination of dehydrogenase activity and the production of CO2 and CH4 accompanying the degradation of polysaccharides in the plant, 1.5 g of each fraction were sealed in a glass bottle with soil-water mixture of 400 g soil and 130 ml water. The bottles were incubated at 30degC for 30 days without shaking. The highest microbial activity was observed in the bottle containing the stem, in which the microbial population reached the stationary state at the 11th day during the incubation period. In the bottle containing leaf, the stationary state of the population was realized at the 25th day during incubation. In both bottles, CH4 formation reached the maximum at the 11th day and then decreased. In the bottle containing root, though microbial activity slowly kept increasing throughout the incubation period, CH4 formation from root was not observed. The production of CO2 was observed prior to CH4 formation in all bottles. (author)

  7. Isotope hydrogeochemistry in exploration for buried and blind mineralization

    International Nuclear Information System (INIS)

    Buried and blind deposits, with no direct geological or geochemical manifestation at the surface, are becoming increasingly important targets in Australia. One of the key exploration challenges relates to assessing and ranking targets established from geophysical and other remotely sensed surveys. Sub-surface geology is reflected in the geochemistry of groundwaters (Giblin, 1996) and hydrogeochemical methods provide a particularly powerful technique in areas of poor surface exposure, deep weathering and where transported overburden obscures the underlying geology (Giblin, 1997). In such areas several hundred samples are used to define locally prospective areas although how these relate to a specific mineralization style may be difficult to determine. The question of proximity to an orebody is fundamental to mineral exploration and isotopic (S, Pb, Sr) methods are uniquely capable of contributing to an answer. The isotopic composition of ores and waters that interact with ores carries important information about the elemental source; S and Pb are direct ore indicators allowing straight-forward interpretation of possible ore associations. The isotopic methods also provide unequivocal evidence for mixing. The isotopic compositions of S, Pb and Sr in rocks are unaffected by weathering and in natural waters are unaffected by precipitation, evaporation or dilution. Isotopic methods provide information that is complementary to that obtainable from major and trace element abundances. The application of integrated isotopic studies to conventional hydrogeochemical interpretations was tested in several areas (Fig. 1); Menninnie Dam (Pb, Zn; Eyre Peninsula SA), Abra (Ag, Pb; Bangemall Basin WA), Benambra (Cu, Zn, Pb: Lachlan Fold Belt Vic), Goonumbla (Cu, Au; Lachlan Fold Belt NSW) and Kanmantoo (Cu, Pb, Zn, Au; Kanmantoo Fold Belt SA). These were chosen to include different deposit types, tectonic regimes, climatic and topographic environments and groundwater chemistry

  8. Solving the sulphur situation : research assesses viability of burying sulphur

    International Nuclear Information System (INIS)

    Oil sands mining companies are looking for ways to manage growing levels of sulphur production from the Athabasca region. Infrastructure is not in place to economically transport the sulphur even though there is a global market for it. Sulphur cannot be stockpiled indefinitely as it can react with air to produce sulphur dioxide. Although above-ground sulphur storage has been regulated for more than 30 years, the underground storage of sulphur is still in a research and development phase. Alberta Sulphur Research Ltd. is currently conducting an ongoing experiment in which 100 tonne test blocks have been buried above and below the water table so that surrounding areas could be monitored over a period of years. A series of tests is being conducted to examine changes in pH in water and sulphate levels. A multi-layered engineering casing to contain the sulphur and prevent seepage is also being investigated. Once stored underground, operators also have to consider how the sulphur will be accessed in the future, as it is subject to government royalties. The storage of sulphur may have economic benefits as the product can be sold when prices are high. Most sulphur produced in Alberta is sold as an export product in the United States for use in products such as fertilizer. Shell Canada penetrated the Chinese market in 2001 and has since become one of Canada's largest sulphur exporters. Shell has also introduced a number of products using sulphur, including fertilizers, enhanced asphalt, and concrete. It was concluded that companies must take action now to mitigate future losses and to utilize current markets in order to remain competitive. 3 figs

  9. FOREWORD: Special section on electromagnetic characterization of buried obstacles

    Science.gov (United States)

    Lesselier, Dominique; Chew, Weng Cho

    2004-12-01

    This Inverse Problems special section on electromagnetic characterization of buried obstacles contains a selection of 14 invited papers, involving 41 authors and 19 research groups worldwide. (Though this section consists of invited papers, the standard refereeing procedures of Inverse Problems have been rigorously observed.) We do not claim to have reached all the high-level researchers in the field, but we believe that we have made a fair attempt. As illustrated by the variety of contributions included, the aim of this special section is to address theoretical and practical inversion problems (and the solutions thereof) that arise in the field of electromagnetic characterization of obstacles (artificial or natural) buried on the Earth or in planetary subsoil. Civil and military engineering, archaeological and environmental issues are typically among those within the scope of the investigation. An example is the characterization of a single (or multiple) obstacle(s) located near the interface or at shallow depths via electromagnetic means operating within relevant frequency bands. However, we also welcomed novel and thought-provoking investigations, even though their direct application to the real world, or even to laboratory-controlled settings, may still be far off. Within this general mathematical and applied framework, the submitted papers focused on a combination of theoretical, computational and experimental developments. They either reviewed the most recent advances in a particular area of research or were an original and specialized contribution. Let us now take the opportunity to remind the readers that this special section harks back (in addition to sharing some common contributors) to two special sections already published in the journal which possessed the same flavour of wave-field inversion and its many applications. They were `Electromagnetic imaging and inversion of the Earth's subsurface', which was published in October 2000 (volume 16, issue 5

  10. Effect of Biostimulation and Bioaugmentation on Degradation of Polyurethane Buried in Soil▿

    OpenAIRE

    Cosgrove, L.; McGeechan, P. L.; Handley, P. S.; Robson, G. D.

    2009-01-01

    This work investigated biostimulation and bioaugmentation as strategies for removing polyurethane (PU) waste in soil. Soil microcosms were biostimulated with the PU dispersion agent “Impranil” and/or yeast extract or were bioaugmented with PU-degrading fungi, and the degradation of subsequently buried PU was determined. Fungal communities in the soil and colonizing buried PU were enumerated on solid media and were analyzed using denaturing gradient gel electrophoresis (DGGE). Biostimulation w...

  11. Pannus Is the New Prepuce? Penile Cancer in a Buried Phallus

    OpenAIRE

    Jared Manwaring; Srinivas Vourganti; Dmitriy Nikolavsky; Valente, Alfredo L.; Timothy Byler

    2015-01-01

    Two males presented to our urology department with complaints of bleeding and malodor from buried phallus within a suprapubic fat pad. Although both men had neonatal circumcisions, advanced penile carcinoma was found in both men. Formal penectomies showed high grade, poorly differentiated squamous cell carcinoma invading the corporal bodies and urethra. Buried penis represents a difficulty in early detection of suspicious lesions but may also provide an environment susceptible to poor hygiene...

  12. Vertical coupling of laser glass microspheres to buried silicon nitride ellipses and waveguides

    OpenAIRE

    Navarro-Urrios, Daniel; Ramirez, Joan Manel; Capuj, Nestor E.; Berencen, Yonder; Garrido, Blas; Tredicucci, Alessandro

    2015-01-01

    We demonstrate the integration of Nd3+ doped Barium-Titanium-Silicate microsphere lasers with a Silicon Nitride photonic platform. Devices with two different geometrical configurations for extracting the laser light to buried waveguides have been fabricated and characterized. The first configuration relies on a standard coupling scheme, where the microspheres are placed over strip waveguides. The second is based on a buried elliptical geometry whose working principle is that of an elliptical ...

  13. Parental effects and flight behaviour in the burying beetle, Nicrophorus vespilloides

    OpenAIRE

    Attisano, Alfredo; Kilner, Rebecca M.

    2015-01-01

    Parents play a key role in determining the phenotype of their offspring. However, relatively few studies have investigated whether parents can change their offspring's behaviour in a sustained way that persists into adulthood. With experiments on the burying beetle, Nicrophorus vespilloides, we investigated how the developmental environment created by parents affects their offspring's wing morphology in adulthood, and the correlated effects on adult flight behaviour. Burying beetles exhibit c...

  14. Imaging of Au nanoparticles deeply buried in polymer matrix by various atomic force microscopy techniques

    International Nuclear Information System (INIS)

    Recently, some papers reported successful imaging of subsurface features using atomic force microscopy (AFM). Some theoretical studies have also been presented, however the imaging mechanisms are not fully understood yet. In the preceeding papers, imaging of deeply buried nanometer-scale features has been successful only if they were buried in a soft matrix. In this paper, subsurface features (Au nanoparticles) buried in a soft polymer matrix were visualized. To elucidate the imaging mechanisms, various AFM techniques; heterodyne force microscopy, ultrasonic atomic force microscopy (UAFM), 2nd-harmonic UAFM and force modulation microscopy (FMM) were employed. The particles buried under 960 nm from the surface were successfully visualized which has never been achieved. The results elucidated that it is important for subsurface imaging to choose a cantilever with a suitable stiffness range for a matrix. In case of using the most suitable cantilever, the nanoparticles were visualized using every technique shown above except for FMM. The experimental results suggest that the subsurface features buried in a soft matrix with a depth of at least 1 µm can affect the local viscoelasticity (mainly viscosity) detected as the variation of the amplitude and phase of the tip oscillation on the surface. This phenomenon presumably makes it possible to visualize such deeply buried nanometer-scale features in a soft matrix. - Highlights: • We visualized subsurface features buried in soft matrix, and investigated its imaging mechanism. • AFM techniques; UAFM, FMM, HFM and 2nd-harmonic UAFM were applied to elucidate the mechanism. • Au nanoparticles buried under 960 nm from surface were visualized, which has never been achieved. • Imaging at contact resonance using a cantilever of suitable stiffness is important. • Subsurface features in a soft matrix affect surface viscoelasticity, which are detected by AFM

  15. Imaging of Au nanoparticles deeply buried in polymer matrix by various atomic force microscopy techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Kuniko [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan); Kobayashi, Kei [Office of Society-Academia Collaboration for Innovation, Kyoto University, Katsura, Nishikyo, Kyoto 615-8520 (Japan); Matsushige, Kazumi [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan); Yamada, Hirofumi, E-mail: h-yamada@kuee.kyoto-u.ac.jp [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan)

    2013-10-15

    Recently, some papers reported successful imaging of subsurface features using atomic force microscopy (AFM). Some theoretical studies have also been presented, however the imaging mechanisms are not fully understood yet. In the preceeding papers, imaging of deeply buried nanometer-scale features has been successful only if they were buried in a soft matrix. In this paper, subsurface features (Au nanoparticles) buried in a soft polymer matrix were visualized. To elucidate the imaging mechanisms, various AFM techniques; heterodyne force microscopy, ultrasonic atomic force microscopy (UAFM), 2nd-harmonic UAFM and force modulation microscopy (FMM) were employed. The particles buried under 960 nm from the surface were successfully visualized which has never been achieved. The results elucidated that it is important for subsurface imaging to choose a cantilever with a suitable stiffness range for a matrix. In case of using the most suitable cantilever, the nanoparticles were visualized using every technique shown above except for FMM. The experimental results suggest that the subsurface features buried in a soft matrix with a depth of at least 1 µm can affect the local viscoelasticity (mainly viscosity) detected as the variation of the amplitude and phase of the tip oscillation on the surface. This phenomenon presumably makes it possible to visualize such deeply buried nanometer-scale features in a soft matrix. - Highlights: • We visualized subsurface features buried in soft matrix, and investigated its imaging mechanism. • AFM techniques; UAFM, FMM, HFM and 2nd-harmonic UAFM were applied to elucidate the mechanism. • Au nanoparticles buried under 960 nm from surface were visualized, which has never been achieved. • Imaging at contact resonance using a cantilever of suitable stiffness is important. • Subsurface features in a soft matrix affect surface viscoelasticity, which are detected by AFM.

  16. Large optical cavity AlGaAs buried heterostructure window lasers

    OpenAIRE

    Blauvelt, H.; Margalit, S.; Yariv, A.

    1982-01-01

    Large optical cavity buried heterostructure window lasers in which only the transparent AlGaAs waveguiding layers, and not the active layer, extend to the laser mirrors have been fabricated. These lasers have threshold currents and differential quantum efficiencies comparable to those of regular large optical cavity buried heterostructure lasers in which the active region extends to the laser mirrors, however the window lasers have been operated under pulsed conditions at three times the powe...

  17. Surgical correction of buried penis after traffic accident – a case report

    OpenAIRE

    Masuda Hiroshi; Azuma Haruhito; Segawa Naoki; Iwamoto Yusaku; Inamoto Teruo; Takasaki Noboru; Katsuoka Yoji

    2004-01-01

    Abstract Background Buried penis, most commonly seen in children, is particularly debilitating in adults, resulting in inability to void while standing and it also affects vaginal penetration. We report a case of buried penis due to a traffic accident, which caused dislocation of the fractured pubic bone that shifted inside and pulled the penis by its suspensory ligament. Case presentation A 55-year-old man was admitted to our hospital with a chief complaint of hidden penis while in the sitti...

  18. Post-liquefaction soil-structure interaction for buried structures: Sensitivity analysis studies

    International Nuclear Information System (INIS)

    The post liquefaction behavior of buried conduits is analyzed and sensitivity analysis is conducted to investigate the damage potential of the forces induced in the buried lifelines following seismically induced liquefaction of the surrounding soil. Various lifeline configurations and loading conditions are considered. The loading conditions considered are: buoyancy forces and permanent ground displacements parallel to the lifeline axis. Pertinent parameters for the soil-lifeline interaction following liquefaction are identified. (author)

  19. Thin films and buried interfaces characterization with X-ray standing waves

    Energy Technology Data Exchange (ETDEWEB)

    Lagomarsino, S. [CNR, Rome (Italy). Istituto Elettronica Stato Solido

    1996-09-01

    The X-ray standing wave techniques is a powerful, non destructive method to study interfaces at the atomic level. Its basic features are described here together with the peculiarities of its applications to epitaxial films and buried interfaces. As examples of applications, experiments carried out on Si/silicide interfaces, on GaAs/InAs/GaAs buried interfaces and on Si/Ge superlattices are shown.

  20. A process for ensuring regulatory compliance at the INEL`s buried waste integrated demonstrations

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, P.G.; Watson, L.R.; Blacker, P.B. [EG and G Idaho, Inc., Idaho Falls, ID (United States). Idaho National Engineering Lab.

    1993-03-01

    The Buried Waste Integrated Demonstration Program is funded by the Department of Energy Office of Technology Development. The mission of this Integrated Demonstration is to identify, evaluate, and demonstrate a suite of innovative technologies for the remediation of radioactive and hazardous waste buried throughout the DOE complex between 1950 and 1970. The program approach to development of a long-range strategy for improving buried waste remediation capabilities is to combine systems analysis with already identified remediation needs for DOE complex buried waste. The systems analysis effort has produced several configuration options (a top-level block diagram of a cradle-to-grave remediation system) capable of remediating the transuranic-contaminated waste pits and trenches at the Idaho National Engineering Laboratory. Technologies for demonstration are selected using three criteria: (a) the ability to satisfy a specific buried waste need, (b) the ability to satisfy functional and operational requirements defined for functional sub-elements in a configuration option, and (c) performance against Comprehensive Environmental Restoration and Compensation Liability Act selection criteria, such as effectiveness, implementability, and cost. Early demonstrations experienced problems with missed requirements, prompting the Buried Waste Integrated Demonstration Program Office to organize a Corrective Action Team to identify the cause and recommend corrective actions. The result of this team effort is the focus of this paper.

  1. Strain mapping with nm-scale resolution for the silicon-on-insulator generation of semiconductor devices by advanced electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, David; Denneulin, Thibaud; Barnes, Jean-Paul; Hartmann, Jean-Michel; Hutin, Louis; Le Royer, Cyrille [CEA, LETI France MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Beche, Armand [CEA, LETI, and FEI France MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Rouviere, Jean-Luc [CEA, INAC, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

    2012-12-15

    Strain engineering in the conduction channel is a cost effective method of boosting the performance in state-of-the-art semiconductor devices. However, given the small dimensions of these devices, it is difficult to quantitatively measure the strain with the required spatial resolution. Three different transmission electron microscopy techniques, high-angle annular dark field scanning transmission electron microscopy, dark field electron holography, and nanobeam electron diffraction have been applied to measure the strain in simple bulk and SOI calibration specimens. These techniques are then applied to different gate length SiGe SOI pFET devices in order to measure the strain in the conduction channel. For these devices, improved spatial resolution is required, and strain maps with spatial resolutions as good as 1 nm have been achieved. Finally, we discuss the relative advantages and disadvantages of using these three different techniques when used for strain measurement.

  2. Strain mapping with nm-scale resolution for the silicon-on-insulator generation of semiconductor devices by advanced electron microscopy

    International Nuclear Information System (INIS)

    Strain engineering in the conduction channel is a cost effective method of boosting the performance in state-of-the-art semiconductor devices. However, given the small dimensions of these devices, it is difficult to quantitatively measure the strain with the required spatial resolution. Three different transmission electron microscopy techniques, high-angle annular dark field scanning transmission electron microscopy, dark field electron holography, and nanobeam electron diffraction have been applied to measure the strain in simple bulk and SOI calibration specimens. These techniques are then applied to different gate length SiGe SOI pFET devices in order to measure the strain in the conduction channel. For these devices, improved spatial resolution is required, and strain maps with spatial resolutions as good as 1 nm have been achieved. Finally, we discuss the relative advantages and disadvantages of using these three different techniques when used for strain measurement.

  3. High-responsivity vertical-illumination Si/Ge uni-traveling-carrier photodiodes based on silicon-on-insulator substrate

    OpenAIRE

    Chong Li; ChunLai Xue; Zhi Liu; Hui Cong; Buwen Cheng; Zonghai Hu; Xia Guo; Wuming Liu

    2016-01-01

    Si/Ge uni-traveling carrier photodiodes exhibit higher output current when space-charge effect is overcome and the thermal effects is suppressed. High current is beneficial for increasing the dynamic range of various microwave photonic systems and simplifying high-bit-rate digital receivers in many applications. From the point of view of packaging, detectors with vertical-illumination configuration can be easily handled by pick-and-place tools and are a popular choice for making photo-receive...

  4. Development of cryogenic readout electronics using fully-depleted-silicon-on-insulator CMOS process for future space borne far-infrared image sensors

    Science.gov (United States)

    Nagata, Hirohisa; Wada, Takehiko; Ikeda, Hirokazu; Arai, Yasuo; Ohno, Morifumi

    2009-12-01

    We measured the static characteristics and noise spectra of FD-SOI-CMOS at liquid helium temperature where many bulk-CMOS transistors suffer from anomalous behaviors on the current-voltage curves such as kink phenomena. The test results showed that the static characteristics depend on the layouts of the FD-SOI-CMOS transistor. While a body floating FD-SOI-CMOS transistor showed strong anomalous effects on the I-V curves, body-tied and ST ones showed much better static characteristics than the body floating one. Using the characteristics derived from the FET measurements, we show that a low power and high gain preamplifier suitable for far-infrared detectors can be designed.

  5. Kelvin probe characterization of buried graphitic microchannels in single-crystal diamond

    Science.gov (United States)

    Bernardi, E.; Battiato, A.; Olivero, P.; Picollo, F.; Vittone, E.

    2015-01-01

    In this work, we present an investigation by Kelvin Probe Microscopy (KPM) of buried graphitic microchannels fabricated in single-crystal diamond by direct MeV ion microbeam writing. Metal deposition of variable-thickness masks was adopted to implant channels with emerging endpoints and high temperature annealing was performed in order to induce the graphitization of the highly-damaged buried region. When an electrical current was flowing through the biased buried channel, the structure was clearly evidenced by KPM maps of the electrical potential of the surface region overlying the channel at increasing distances from the grounded electrode. The KPM profiling shows regions of opposite contrast located at different distances from the endpoints of the channel. This effect is attributed to the different electrical conduction properties of the surface and of the buried graphitic layer. The model adopted to interpret these KPM maps and profiles proved to be suitable for the electronic characterization of buried conductive channels, providing a non-invasive method to measure the local resistivity with a micrometer resolution. The results demonstrate the potential of the technique as a powerful diagnostic tool to monitor the functionality of all-carbon graphite/diamond devices to be fabricated by MeV ion beam lithography.

  6. Kelvin probe characterization of buried graphitic microchannels in single-crystal diamond

    International Nuclear Information System (INIS)

    In this work, we present an investigation by Kelvin Probe Microscopy (KPM) of buried graphitic microchannels fabricated in single-crystal diamond by direct MeV ion microbeam writing. Metal deposition of variable-thickness masks was adopted to implant channels with emerging endpoints and high temperature annealing was performed in order to induce the graphitization of the highly-damaged buried region. When an electrical current was flowing through the biased buried channel, the structure was clearly evidenced by KPM maps of the electrical potential of the surface region overlying the channel at increasing distances from the grounded electrode. The KPM profiling shows regions of opposite contrast located at different distances from the endpoints of the channel. This effect is attributed to the different electrical conduction properties of the surface and of the buried graphitic layer. The model adopted to interpret these KPM maps and profiles proved to be suitable for the electronic characterization of buried conductive channels, providing a non-invasive method to measure the local resistivity with a micrometer resolution. The results demonstrate the potential of the technique as a powerful diagnostic tool to monitor the functionality of all-carbon graphite/diamond devices to be fabricated by MeV ion beam lithography

  7. LEUPROLIDE INHIBITS MARBLE-BURYING BEHAVIOR VIA MODULATION OF 5-HT1B RECEPTOR

    Directory of Open Access Journals (Sweden)

    Parle Milind

    2011-04-01

    Full Text Available Obsessive compulsive disorder (OCD is characterized by intrusive thoughts followed by repetitive behaviors. Serotonin-related genes found in OCD include those required for coding of 5-HT transporter and 5-HT receptors (5-HT2A, 5-HT2B, 5-HT2C and 5-HT1B. Marble-burying behavior of mice is a well-accepted paradigm to screen anti-compulsive activity. The aim of this study was to evaluate the effect of leuprolide alone and it’s combination with sumatriptan or ondansetron on marble-burying behavior of mice. Leuprolide (100, 200 & 300 µg kg-1s.c. dose-dependently showed anti-compulsive effect, causing statistically significant inhibition of marble-burying behavior of mice. The prior treatment with 5HT1B/1D/1F agonist, sumatriptan (0.1 mg kg-1 s.c. potentiated the inhibitory effect of leuprolide (LHRH agonist on marble burying behavior of mice. Furthermore, prior treatment with 5HT3 antagonist, ondansetron (2 mg kg-1 s.c. did not affect the inhibitory effect of leuprolide (200 µg kg-1s.c. on marble burying behavior of mice.

  8. GPR investigations in galleries buried inside a karstified limestone formation

    Science.gov (United States)

    Rousset, D.; Sénéchal, G.; Gaffet, S.

    2009-04-01

    A large scientific program of geophysical investigations is presently performed inside the Low-Noise Underground Laboratory (Laboratoire Souterrain à Bas Bruit / LSBB, Rustrel, France) which is an decomissioned underground missile control center, buried in a karstified limestone formation. One of the goals of this project is the understanding of the water circulation inside the structure. This experimental site offers a unique opportunity of perfoming measurements within an unweathered limestone massif. The tunnel has been dug in lower cretaceous limestone which is characterized by a low clay content, high electrical resistivity. The dip is around 25 degrees and vertical faults locally affect the structure. The studied zone is located in south-eastern France (Provence) and is characterized by a mediterranean climate with long dry periods and strong, short events of rain. This phenomenon induces large variations of water content within the karstified limestone from dry to saturated conditions. Analysis of the spatial and temporal variations of the water flow in a karstified limestones needs to define the geological context and the adequate geophysical methods. GPR offers a good tradeoff between resolution and ease of use on one hand and investigation depth on the other hand. We present some GPR profiles which have been acquired in April 2008 after a quite long and strong period of rain, inducing a complete water saturation inside the karstified massif. We used several RAMAC shielded antennas from 100 to 500 MHz. The longest profile is around 600 m long, with a 20 cm spacing, running from a raw to a concrete gallery. These data sets are characterized by a very good signal to noise ratio and a signal penetration, up to 18 meters. Signal processing includes very low frequency filtering, amplitude compensation, keeping lateral relative attenuation and ringing suppression. Final sections includes migration and time to depth conversion or depth migration. The estimated

  9. Predicting arsenic concentrations in the porewaters of buried uranium mill tailings

    Science.gov (United States)

    Langmuir, Donald; Mahoney, John; MacDonald, Anjali; Rowson, John

    1999-10-01

    The proposed JEB Tailings Management Facility (TMF) to be emplaced below the groundwater table in northern Saskatchewan, Canada, will contain uranium mill tailings from McClean Lake, Midwest and Cigar Lake ore bodies, which are high in arsenic (up to 10%) and nickel (up to 5%). A serious concern is the possibility that high arsenic and nickel concentrations may be released from the buried tailings, contaminating adjacent groundwaters and a nearby lake. Laboratory tests and geochemical modeling were performed to examine ways to reduce the arsenic and nickel concentrations in TMF porewaters so as to minimize such contamination from tailings buried for 50 years and longer. The tests were designed to mimic conditions in the mill neutralization circuit (3 hr tests at 25°C), and in the TMF after burial (5-49 day aging tests). The aging tests were run at, 50, 25 and 4°C (the temperature in the TMF). In order to optimize the removal of arsenic by adsorption and precipitation, ferric sulfate was added to tailings raffinates having Fe/As ratios of less that 3-5. The acid raffinates were then neutralized by addition of slaked lime to nominal pH values of 7, 8, or 9. Analysis and modeling of the test results showed that with slaked lime addition to acid tailings raffinates, relatively amorphous scorodite (ferric arsenate) precipitates near pH 1, and is the dominant form of arsenate in slake limed tailings solids except those high in Ni and As and low in Fe, in which cabrerite-annabergite (Ni, Mg, Fe(II) arsenate) may also precipitate near pH 5-6. In addition to the arsenate precipitates, smaller amounts of arsenate are also adsorbed onto tailings solids. The aging tests showed that after burial of the tailings, arsenic concentrations may increase with time from the breakdown of the arsenate phases (chiefly scorodite). However, the tests indicate that the rate of change decreases and approaches zero after 72 hrs at 25°C, and may equal zero at all times in the TMF at 4

  10. A Newton method for a simultaneous reconstruction of an interface and a buried obstacle from far-field data

    International Nuclear Information System (INIS)

    This paper is concerned with the inverse problem of scattering of time-harmonic acoustic waves from a penetrable and a buried obstacle. By introducing a related transmission scattering problem, a Newton iteration method is proposed to simultaneously reconstruct both the penetrable interface and the buried obstacle inside from far-field data. The main feature of our method is that we do not need to know the type of boundary conditions on the buried obstacle. In particular, the boundary condition on the buried obstacle can also be determined simultaneously by the method. Finally, numerical examples using multi-frequency data are carried out to illustrate the effectiveness of our method. (paper)

  11. Oxygen dynamics around buried lesser sandeels Ammodytes tobianus (Linnaeus 1785): mode of ventilation and oxygen requirements

    DEFF Research Database (Denmark)

    Behrens, Jane W; Stahl, Henrik J; Steffensen, John F;

    2007-01-01

    plume with <15% air saturation around the gills. During this quasi-steady ventilation mode, fish extracted 86.2+/-4.8% (N=7) of the oxygen from the inspired water. However, 13% of the investigated fish (2 of 15) occasionally wriggled their bodies and thereby transported almost fully air-saturated water...... down along the body, referred to as ;plume ventilation'. Yet, within approximately 30 min the oxic plume was replenished by oxygen-depleted water from the gills. The potential for cutaneous respiration by the buried fish was thus of no quantitative importance. Calculations derived by three independent......The oxygen environment around buried sandeels (Ammodytes tobianus) was monitored by planar optodes. The oxygen penetration depth at the sediment interface was only a few mm. Thus fish, typically buried at 1-4 cm depth, were generally in anoxic sediment. However, they induced an advective transport...

  12. Atomic friction at exposed and buried graphite step edges: Experiments and simulations

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Zhijiang; Martini, Ashlie, E-mail: amartini@ucmerced.edu [School of Engineering, University of California Merced, 5200 N. Lake Road, Merced, California 95343 (United States)

    2015-06-08

    The surfaces of layered materials such as graphite exhibit step edges that affect friction. Step edges can be exposed, where the step occurs at the outmost layer, or buried, where the step is underneath another layer of material. Here, we study friction at exposed and buried step edges on graphite using an atomic force microscope (AFM) and complementary molecular dynamics simulations of the AFM tip apex. Exposed and buried steps exhibit distinct friction behavior, and the friction on either step is affected by the direction of sliding, i.e., moving up or down the step, and the bluntness of the tip. These trends are analyzing in terms of the trajectory of the AFM tip as it moves over the step, which is a convolution of the topography of the surface and the tip shape.

  13. Electrochemical deposition of buried contacts in high-efficiency crystalline silicon photovoltaic cells

    DEFF Research Database (Denmark)

    Jensen, Jens Arne Dahl; Møller, Per; Bruton, Tim;

    2003-01-01

    sidewall texture, with a grain-size decreasing from the center to the edges of the buried Cu contacts and a pronounced lateral growth outside the laser-cut grooves. The measured specific contact resistances of the buried contacts was better than the production standard. Overall performance of the new PV...... cells was equal to the production standard with measured efficiencies up to 16.9%.......This article reports on a newly developed method for electrochemical deposition of buried Cu contacts in Si-based photovoltaic ~PV! cells. Contact grooves, 20 mm wide by 40 mm deep, were laser-cut into Si PV cells, hereafter applied with a thin electroless NiP base and subsequently filled with Cu...

  14. A "watch window" technique for monitoring buried free jejunum flaps during circumferential pharyngolaryngectomy reconstruction.

    Science.gov (United States)

    Li, Quan; Zhang, Xin-Rui; Liu, Xue-Kui; Zhang, Zhi-Gang; Liu, Wei-Wei; Li, Hao; Guo, Zhu-Ming

    2012-07-01

    The free jejunum flap approach is the optimal option for circumferential pharyngolaryngectomy reconstruction. In this study, we designed a "watch window" for monitoring buried free jejunum flaps, thereby allowing us to assess graft viability. From 2007 to 2011, 14 patients with hypopharyngeal cancer underwent circumferential pharyngolaryngectomy that was reconstructed using a free jejunum flap at the Sun Yat-sen University Cancer Centre. During the closing of the neck incision, a "watch window" was designed for postoperative monitoring. Two patients experienced thrombosis of the pedicle. One was detected early and successfully rescued by removal of the thrombosis, the other one managed with a second free jejunum flap. The success rate of the buried flaps was 92.9%. No pharyngocutaneous fistulas or strictures occurred. All patients eventually resumed oral feeding and swallowing. The "watch window" technique for monitoring buried free jejunum flaps is simple, reliable and useful for finding vascular problems. Level of evidence Case series. PMID:22116384

  15. Atomic friction at exposed and buried graphite step edges: Experiments and simulations

    International Nuclear Information System (INIS)

    The surfaces of layered materials such as graphite exhibit step edges that affect friction. Step edges can be exposed, where the step occurs at the outmost layer, or buried, where the step is underneath another layer of material. Here, we study friction at exposed and buried step edges on graphite using an atomic force microscope (AFM) and complementary molecular dynamics simulations of the AFM tip apex. Exposed and buried steps exhibit distinct friction behavior, and the friction on either step is affected by the direction of sliding, i.e., moving up or down the step, and the bluntness of the tip. These trends are analyzing in terms of the trajectory of the AFM tip as it moves over the step, which is a convolution of the topography of the surface and the tip shape

  16. Attenuation characteristics of the fundamental modes that propagate in buried iron water pipes.

    Science.gov (United States)

    Long, R; Lowe, M; Cawley, P

    2003-09-01

    The attenuation of the fundamental non-torsional modes that propagate down buried iron water pipes has been studied. The mode shapes, mode attenuation due to leakage into the surrounding medium and the scattering of the modes as they interact with pipe joints and fittings have been investigated. In the low frequency region the mode predicted to dominate over significant propagation distances approximates a plane wave in the water within the pipe. The established acoustic technique used to locate leaks in buried iron water pipes assumes that leak noise propagates as a single non-dispersive mode at a velocity related to the low frequency asymptote of this water borne mode. Experiments have been conducted on buried water mains at test sites in the UK to verify the attenuation and velocity dispersion predictions. PMID:12919686

  17. 3D Imaging of Dielectric Objects Buried under a Rough Surface by Using CSI

    Directory of Open Access Journals (Sweden)

    Evrim Tetik

    2015-01-01

    Full Text Available A 3D scalar electromagnetic imaging of dielectric objects buried under a rough surface is presented. The problem has been treated as a 3D scalar problem for computational simplicity as a first step to the 3D vector problem. The complexity of the background in which the object is buried is simplified by obtaining Green’s function of its background, which consists of two homogeneous half-spaces, and a rough interface between them, by using Buried Object Approach (BOA. Green’s function of the two-part space with planar interface is obtained to be used in the process. Reconstruction of the location, shape, and constitutive parameters of the objects is achieved by Contrast Source Inversion (CSI method with conjugate gradient. The scattered field data that is used in the inverse problem is obtained via both Method of Moments (MoM and Comsol Multiphysics pressure acoustics model.

  18. Physical Modelling on Detecting Buried Object Using Electrical Resistivity Imaging (ERI)

    Science.gov (United States)

    Hazreek, Z. A. M.; Nizam, Z. M.; Azhar, A. T. S.; Aziman, M.; Shaylinda, M. Z. N.

    2016-07-01

    This study focused on the evaluation of electrical resistivity method (ERM) for buried object detection and its relationship due to the different stiffness of material. In the past, the conventional method to detect the buried structure was face some limitation due to the time and cost. For example, previous approach related to the trial and error excavation has always expose to some risky outcome due to the uncertainties of the buried object location. Hence, this study introduced an alternative technique with particular reference to resistivity method to detect and evaluate the buried object with different strength of stiffness. The experiment was performed based on field miniature model (small scale study) using soil trial embankment made by lateritic soil and various concrete cube strengths (grade 20, 25 and 30) representing buried object with different conditions. 2D electrical resistivity test (electrical resistivity imaging) was perform using ABEM Terrameter SAS4000 during the data acquisition while the raw data was process using RES2DINV software. It was found that the electrical resistivity method was able to detect the buried concrete structures targeted based on the contrast of the electrical resistivity image produced. Moreover, three different strength of concrete cube were able to be differentiated based on the electrical resistivity values (ERV) obtained. This study found that the ERV of concrete cube for grade 20, 25 and 30 were 170 Ωm, 227 Ωm and 503 Ωm, respectively. Hence, this study shows that the ERV has a strong relationship with different stiffness of material thus applicable to be a useful alternative tool in underground structure detection.

  19. Evaluation of the graphite electrode DC arc furnace for the treatment of INEL buried wastes

    International Nuclear Information System (INIS)

    The past practices of DOE and its predecessor agencies in burying radioactive and hazardous wastes have left DOE with the responsibility of remediating large volumes of buried wastes and contaminated soils. The Buried Waste Integrated Demonstration (BWID), has chosen to evaluate treatment of buried wastes at the Idaho National Engineering Laboratory (INEL). Because of the characteristics of the buried wastes, the potential for using high-temperature thermal treatment technologies is being evaluated. The soil-waste mixture at INEL, when melted or vitrified, produces a glass/ceramic referred to as iron-enriched basalt (IEB). One potential problem with producing the IEB material is the high melting temperature of the waste and soil (1,400-1,600 degrees C). One technology that has demonstrated capabilities to process high melting point materials is the plasma arc heated furnace. A three-party program was initiated and the program involved testing an engineering-scale DC arc furnace to gain preliminary operational and waste processibility information. It also included the design, fabrication, and evaluation of a second-generation, pilot-scale graphite electrode DC arc furnace. Widely ranging simulants of INEL buried waste were prepared and processed in the Mark I furnace. The tests included melting of soils with metals, sludges, combustibles, and simulated drums. Very promising results in terms of waste product quality, volume reduction, heating efficiency, and operational reliability and versatility were obtained. The results indicate that the graphite electrode DC arc technology would be very well suited for treating high melting point wastes such as those found at INEL. The graphite electrode DC arc furnace has been demonstrated to be very simple, yet effective, with excellent prospects for remote or semi-remote operation

  20. Mines buried in dry and saturated soils : blast experiments, soil modeling and simulations

    OpenAIRE

    Roger, Eve

    2015-01-01

    In recent conflicts, vehicles have been facing underbelly attacks involving a large quantity of buried explosive. A part of the energy is absorbed by the deformation of the belly. Still the vehicle is subjected to the impulse transmitted by the detonation which may severely injure occupants. The intensity of the impulse is highly dependent on three main parameters which are the degree of saturation of the soil, the nature of the soil in which the explosive is buried and the depth of burial of...

  1. LEUPROLIDE INHIBITS MARBLE-BURYING BEHAVIOR VIA MODULATION OF 5-HT1B RECEPTOR

    OpenAIRE

    Parle Milind; Gaikwad Uday

    2011-01-01

    Obsessive compulsive disorder (OCD) is characterized by intrusive thoughts followed by repetitive behaviors. Serotonin-related genes found in OCD include those required for coding of 5-HT transporter and 5-HT receptors (5-HT2A, 5-HT2B, 5-HT2C and 5-HT1B). Marble-burying behavior of mice is a well-accepted paradigm to screen anti-compulsive activity. The aim of this study was to evaluate the effect of leuprolide alone and it’s combination with sumatriptan or ondansetron on marble-burying behav...

  2. Seed longevity of Eragrostis plana Nees buried in natural grassland soil

    OpenAIRE

    Renato Borges de Medeiros; Telmo Focht; Leandro Luiz Menegon; Mário Ruschel Freitas

    2014-01-01

    The objective of this research was to evaluate the seed longevity of Eragrostis plana Nees buried at different soil depths, in a natural-grassland area in the Pampa biome (46 m altitude, 30º05´S and 51º40´W) of Rio Grande do Sul State, Brazil. The experimental design was a split-plot type in complete blocks with two factors: seeds buried at five different depth levels (soil surface and 2.5, 5, 10 and 20 cm) and seven exhumation dates. The blocks were allocated in natural grassland grazed by c...

  3. In-situ characterisation of a buried 137Cs source in the frame of nuclear forensics

    International Nuclear Information System (INIS)

    An approach is demonstrated, through simulations using MCNP, to characterise buried radioactive sources, in terms of their depth, radioactivity and location of their edges in the case of a volumetric one. The approach involves scanning of the sources with a collimated HPGe detector, positioned vertically and at an angle. The sought parameters to characterise the sources considered, were accurately reproduced. The approach was verified experimentally for 137Cs cuboid and point buried sources. The parameters of interest were determined to within 22 % of the actual values. (author)

  4. Testing MODFLOW-LGR for simulating flow around Buried Quaternary valleys - synthetic test cases

    DEFF Research Database (Denmark)

    Vilhelmsen, Troels Norvin; Christensen, Steen

    abstraction. To enable effective administration of the groundwater resources new methods need to be investigated to improve simulation of local scale flow in buried valleys that interact with surrounding regional groundwater systems. The purpose of this synthetic case study is to test the Local Grid Re......­finement (LGR) method developed for MODFLOW-2005 for simulation of groundwater flow in areas containing buried valleys. The tests are conducted as comparative analysis between simulations made with a globally refi­ned model, a locally re­fined model, and a globally coarse model, respectively. Based on the...

  5. Gravity field separation and mapping of buried quaternary valleys in Lolland, Denmark using old geophysical data

    DEFF Research Database (Denmark)

    Møller, M.J.; Olsen, Henrik; Ploug, C.;

    2007-01-01

    In this paper we utilise the old industrial data for planning new surveys. The overall purpose is a detailed mapping of possible aquifers for the island of Lolland, Denmark. This is done through detection and modelling of the buried quaternary valleys, which either can serve as potential aquifers...... or potential aquifer barriers. The present paper deals only with one aspect of a larger study; namely a case story leading to the detection of unknown buried valleys and the first attempts to model them in 3D from gravity and seismics. Also, the emphasis here is not on any theoretical or even...

  6. Buried waste integrated demonstration fiscal year 1992 close-out report

    International Nuclear Information System (INIS)

    The mission of the Buried Waste Integrated Demonstration Program (BWID) is to support the development and demonstration of a suite of technologies that when integrated with commercially-available baseline technologies form a comprehensive remediation system for the effective and efficient remediation of buried waste disposed of throughout the US Department of Energy complex. To accomplish this mission of identifying technological solutions for remediation deficiencies, the Office of Technology Development initiated the BWID at the Idaho National Engineering Laboratory in fiscal year (FY)-91. This report summarizes the activities of the BWID Program during FY-92

  7. Buried Anode Device Development: Cooperative Research and Development Final Report, CRADA Number CRD-11-451

    Energy Technology Data Exchange (ETDEWEB)

    Tenent, R.

    2015-03-01

    The possibility of a reflecting electrochromic device is very attractive, and the 'Buried Anode' architecture developed at NREL could yield such a device. The subject of this cooperative agreement will be the development and refinement of a Buried Anode device process. This development will require the active involvement of NREL and US e-Chromic personnel, and will require the use of NREL equipment as much as possible. When this effort is concluded, US e-Chromic will have enough information to construct a pilot production line, where further development can continue.

  8. Creation and characterization of buried microstructures in diamond by ion implantation

    International Nuclear Information System (INIS)

    At the end of range of MeV ions in diamond, black spots are created corresponding to the Bragg peak in the stopping power; the characteristics of which are not well understood but which may have application in the micromachining of diamond. This paper reports on the initial findings of studies to determine the physical properties of these buried black spots, while exploring how to optimally fabricate microstructures within the diamond. We have created buried 3-D structures in single crystal diamond by means of deep implantation with a focussed ion microbeam, over a wide range of fluences. Characterization is performed by confocal Raman spectroscopy. (author). 13 refs., 6 figs

  9. A parametric study of the effects of soil properties on seismic response of buried vaults

    International Nuclear Information System (INIS)

    This paper examines the effects of soil properties on the seismic response of buried vault structures similar to the tanks located in many Department of Energy facilities for containing high-level radioactive wastes. The study was pursued through a parametric analysis using the computer program SASSI. Both uniform and layered soil properties were include in the investigation. The response parameters of a buried vault to a seismic motion were analyzed for different soil properties to quantify their potential effects. The results of the study are presented in this paper

  10. Centrifuge modelling of lateral displacement of buried pipelines; Modelagem fisica centrifuga de flambagem lateral de dutos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Jose Renato Moreira da Silva de; Almeida, Marcio de Souza Soares de; Marques, Maria Esther Soares; Almeida, Maria Cascao Ferreira de [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE); Costa, Alvaro Maia da [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2003-07-01

    This work discusses soil-structure interaction applied to the buckling phenomena of buried pipelines subjected to heated oil flow. A set of physical modelling tests on lateral buckling of pipelines buried on soft clay is presented using COPPE/UFRJ geotechnical centrifuge. A 1:30 pipeline model was moved side ward through a soft clay layer during centrifuge flight, varying the burial depth, in order to simulate the lateral buckling in plane strain condition. The results show different behaviour concerning horizontal and vertical forces measured at pipeline level due to soil reaction. (author)

  11. Latex-modified grouts for in-situ stabilization of buried transuranic/mixed waste

    International Nuclear Information System (INIS)

    The Department of Applied Science at Brookhaven national Laboratory was requested to investigate latex-modified grouts for in-situ stabilization of buried TRU/mixed waste for INEL. The waste exists in shallow trenches that were backfilled with soil. The objective was to formulate latex-modified grouts for use with the jet grouting technique to enable in-situ stabilization of buried waste. The stabilized waste was either to be left in place or retrieved for further processing. Grouting prior to retrieval reduces the potential release of contaminants. Rheological properties of latex-modified grouts were investigated and compared with those of conventional neat cement grouts used for jet grouting

  12. Tolerance to the Substitution of Buried Apolar Residues by Charged Residues in the Homologous Protein Structures

    OpenAIRE

    Balaji, S.; Aruna, S.; N. Srinivasan

    2003-01-01

    Occurrence and accommodation of charged amino acid residues in proteins that are structurally equivalent to buried non-polar residues in homologues have been investigated. Using a dataset of 1,852 homologous pairs of crystal structures of proteins available at 2A or better resolution, 14,024 examples of apolar residues in the structurally conserved regions replaced by charged residues in homologues have been identified. Out of 2,530 cases of buried apolar residues, 1,677 of the equivalent cha...

  13. A novel SOI MESFET by reducing the electric field crowding for high voltage applications

    Science.gov (United States)

    Orouji, Ali A.; Jam, Moein Eslami; Nejaty, Mohammad

    2014-08-01

    In this paper, a novel silicon-on-insulator (SOI) metal-semiconductor field-effect transistor (MESFET) is presented by reducing the electric field crowding. The charge distribution in channel modifies by reducing the electric field crowding and results in the breakdown voltage (VBR) improves. To reduce the electric field crowding, a buried field plate (BFP) is employed in the buried oxide of the SOI MESFET and connected to source. DC and frequency response characteristics of the SOI MESFET with BFP (BFP-SOI MESFET) are analyzed via a 2-D numerical simulation and the results are compared with characteristics of a conventional SOI MESFET (C-SOI MESFET) structure. The BFP has outstanding effect on the VBR of the device. The VBR of the proposed BFP-SOI MESFET improves by 84% compared with that of the C-SOI MESFET. Although the saturation drain current of the proposed structure has decreased to a small extent, 37% increase in maximum power density is obtained. In addition, the proposed structure showed an approximately 70% decrease in the gate-drain capacitance (Cgd), which in-turn resulted in 5 dB maximum available gain (MAG) improvement at 2 GHz. As a result of employing the buried field plate, the BFP SOI-MESFET has an outstanding DC and frequency response performance compared with the C-SOI MESFET.

  14. A comprehensive inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the INEL RWMC during the years 1984-2003, Volume 3

    International Nuclear Information System (INIS)

    This is the third volume of this comprehensive report of the inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the Idaho National Engineering Laboratory. Appendix B contains a complete printout of contaminant inventory and other information from the CIDRA Database and is presented in volumes 2 and 3 of the report

  15. A comprehensive inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the INEL RWMC during the years 1984-2003, Volume 2

    International Nuclear Information System (INIS)

    This is the second volume of this comprehensive report of the inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the Idaho National Engineering Laboratory. Appendix B contains a complete printout of contaminant inventory and other information from the CIDRA Database and is presented in volumes 2 and 3 of the report

  16. Evolution and recrystallization of buried amorphous layers in Al22+ implanted 4H-SiC

    International Nuclear Information System (INIS)

    Epitaxial 4H-SiC has been irradiated at 150 K with 1.1 MeV Al22+ molecular ions to fluences ranging from 1.5x1013 to 8.00x1014 Al+ cm-2. The evolution and isochronal recovery of the buried amorphous layers at higher fluences were investigated by in situ Rutherford backscattering spectrometry using a 2.0 MeV He+ beam along the channeling direction. The damage accumulation at the damage peak in the as-implanted samples indicates a sigmoidal dependence on ion fluence, and a buried amorphous layer is formed at 2.00x1014 Al+ cm-2. The buried amorphous thickness increased rapidly at 2.00x1014 Al+ cm-2 and eventually saturated at a thickness of ∼500 nm at the highest fluence. The relative amount of recovery at any depth decreased with increasing ion fluence for temperatures up to 870 K, and once a thick buried amorphous layer is produced, recovery is only observed at the crystalline-amorphous interface. Defect annihilation processes are responsible for the slight recrystallization and sharpening of the damage profiles that are observed at these low annealing temperatures

  17. OMRC Technology Effectively Develops the Massive Thick Metamorphic Buried Hill Reservoir

    Institute of Scientific and Technical Information of China (English)

    Ren Fangxiang; Zhang Fangli; Sun Yan; Gong Yaojin; Xu Ning; Zhao Zhigang

    2010-01-01

    @@ Introduction Optimized maximum reservoir contact technology(OMRC)is developed based on the maximum reservoir contact(MRC)technology,which is a kind of technology to optimize candidate multilaterals with appropriate specification based on the reservoir conditions.By applying the technology in XLT buried hill reservoir in Liaohe Oilfield satisfactory effects are obtained.

  18. Geologic environment of hvdc ground currents as related to buried pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Bechtold, I.C.; Jahns, R.H.

    1969-01-01

    The principal concern is the possible effects of hvdc power systems on existing buried structures, such as underground pipelines and other metallic installations, through which current may flow either to or from the earth if such current is impressed on the metallic conductors of these structures.

  19. Buried late Pleistocene fluvial channels on the inner continental shelf off Vengurla, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    SubbaRaju, L.V.; Krishna, K.S.; Chaubey, A.K.

    with sediments. Cross sectional dimensions between 15 to 100 m width and 2 to 6 m depth suggest a fluvial origin of the channels. These buried channels appear to mark former positions of rivers flowing from the nearby coast and debouching into the Arabian Sea...

  20. Application of EM tomography to detect a buried pipe; EM tomography no maisetsukan tansa eno tekiyorei

    Energy Technology Data Exchange (ETDEWEB)

    Sakashita, S. [OYO Corp., Tokyo (Japan)

    1996-10-01

    EM tomography was applied to detect buried pipes. Underground radar exploration method is limited to 10m in depth. Positive use of bored holes is desirable, and in such case, magnetic logging based on the magnetic susceptibility (MS) contrast between buried body and surrounding ground is effective. The primary magnetic field is generated by coil current, and the secondary one is generated by the primary one responding to foreign bodies in the ground. Since the measured primary magnetic field of low frequency within 10Hz can be treated as static magnetic field responding to MS in the ground, it is useful to determine MS distributions. Since the measured magnetic field of high frequency within 100kHz can be treated as induction field responding to conductivity in the ground, it is useful to determine resistivity distributions. The EM tomography which can image both above distributions by using electromagnetic wave in a wide frequency range, was applied to detect buried pipes. The EM tomography could detect an buried foreign body of 3m in diameter at 10m in distance between bored holes. The theoretical equation for analysis was also derived. 5 refs., 9 figs., 1 tab.

  1. Series resistance effect on the output parameters of buried emitter silicon solar cells

    OpenAIRE

    Gamal M. Eldallal; Mohamed Y. Feteha; Mousaa, Mostafa E.

    1999-01-01

    A realistic distributed equivalent circuit for the buried emitter silicon solar cell is presented taking into consideration the carriers paths through the planar and vertical junctions. In addition, a new theoretical model for the cell characteristics including the cell's mismatching, series resistance, different junctions (planar and vertical) and junctions geometry is considered in this work. The results are compared with the published data.

  2. Bioelectrochemical denitrification on biocathode buried in simulated aquifer saturated with nitrate-contaminated groundwater.

    Science.gov (United States)

    Nguyen, Van Khanh; Park, Younghyun; Yu, Jaecheul; Lee, Taeho

    2016-08-01

    Nitrate contamination in aquifers has posed human health under high risk because people still rely on groundwater withdrawn from aquifers as drinking water and running water sources. These days, bioelectrochemical technologies have shown a great number of benefits for nitrate remediation via autotrophic denitrification in groundwater. This study tested the working possibility of a denitrifying biocathode when installed into a simulated aquifer. The reactors were filled with sand and synthetic groundwater at various ratios (10, 50, and 100 %) to clarify the effect of various biocathode states (not-buried, half-buried, and fully buried) on nitrate reduction rate and microbial communities. Decreases in specific nitrate reduction rates were found to be correlated with increases in sand/medium ratios. A specific nitrate reduction rate of 322.6 mg m(-2) day(-1) was obtained when the biocathode was fully buried in an aquifer. Microbial community analysis revealed slight differences in the microbial communities of biocathodes at various sand/medium ratios. Various coccus- and rod-shaped bacteria were found to contribute to bioelectrochemical denitrification including Thiobacillus spp. and Paracoccus spp. This study demonstrated that the denitrifying biocathode could work effectively in a saturated aquifer and confirmed the feasibility of in situ application of microbial electrochemical denitrification technology. PMID:27117152

  3. Metallization improvement on fabrication of interdigitated backside and double sided buried contact solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jiun-Hua; Cotter, Jeffrey E. [Center of Excellence for Advanced Silicon Photovoltaics and Photonics, University of New South Wales, Sydney NSW 2052 (Australia)

    2005-04-01

    Metallization based on electroless metal plating of nickel and copper is a simple, cost-effective process used in the fabrication of Buried Contact silicon solar cells. Whereas the electroless Ni-Cu metallization scheme works well for metal deposition on early Buried Contact solar cells, in which deposition was required only on phosphorus diffused contact regions, more care is required for advanced Buried Contact solar cell designs that require simultaneous deposition on to both phosphorus and boron diffused contact regions. In this paper, we examine two key issues related to the metallization in these solar cells. Firstly we demonstrate an improved buffered hydrofluoric acid etch process for simultaneous removal of borosilicate and borophosphosilicate glasses from the contact regions prior to electroless deposition of nickel with good etch selectivity against silicon dioxide masking films. Secondly, we demonstrate an improved process for nucleation of the nickel layer on both phosphorus and boron diffused contact areas based on immersion palladium chloride activation of the plating surfaces. N-type double-sided buried contact solar cells metallized by processing introduced in this study show improvement on absolute efficiency of more than 3%.

  4. Finite element analysis of fluid-structure interaction in buried liquid-conveying pipeline

    Institute of Scientific and Technical Information of China (English)

    朱庆杰; 陈艳华; 刘廷权; 代兆立

    2008-01-01

    Long distance buried liquid-conveying pipeline is inevitable to cross faults and under earthquake action,it is necessary to calculate fluid-structure interaction(FSI) in finite element analysis under pipe-soil interaction.Under multi-action of site,fault movement and earthquake,finite element model of buried liquid-conveying pipeline for the calculation of fluid structure interaction was constructed through combinative application of ADINA-parasolid and ADINA-native modeling methods,and the direct computing method of two-way fluid-structure coupling was introduced.The methods of solid and fluid modeling were analyzed,pipe-soil friction was defined in solid model,and special flow assumption and fluid structure interface condition were defined in fluid model.Earthquake load,gravity and displacement of fault movement were applied,also model preferences.Finite element research on the damage of buried liquid-conveying pipeline was carried out through computing fluid-structure coupling.The influences of pipe-soil friction coefficient,fault-pipe angle,and liquid density on axial stress of pipeline were analyzed,and optimum parameters were proposed for the protection of buried liquid-conveying pipeline.

  5. Numerical and experimental investigation of flow and scour around a half-buried sphere

    DEFF Research Database (Denmark)

    Dixen, Martin; Sumer, B. Mutlu; Fredsøe, Jørgen

    2013-01-01

    The paper describes the results of a numerical and experimental investigation of flow and scour around a half-buried sphere exposed to a steady current. Hot-film bed shear stress and Laser Doppler Anemometer measurements were made with a half sphere mounted on the smooth bed in an open channel. T...

  6. Modified Double-Eyelid Blepharoplasty Using the Single-Knot Continuous Buried Non-Incisional Technique

    Directory of Open Access Journals (Sweden)

    Kyung-Chul Moon

    2013-07-01

    Full Text Available Background Buried non-incisional double-eyelid blepharoplasty is a popular aesthetic procedure. Although various modified continuous suture techniques have been used to create a more natural appearance and to reduce downtime, complications such as loosening of the double fold, asymmetry, and foreign body reactions have been observed.Methods This study included 250 patients who underwent double-eyelid blepharoplasty between March 1997 and November 2012 using a modified single-knot continuous buried non-incisional technique. With 4 stab incisions in the upper eyelids, one of two needles loaded with double-armed 7-0 nylon was passed in one direction alternately through the dermis and the conjunctiva, while the other needle was passed subconjunctivally in the opposite direction. Both ends of the sutures were knotted within a lateral stab incision of the upper eyelids and were buried in the orbicularis oculi muscle.Results Most patients displayed satisfactory aesthetic results, and no significant complications occurred. There was no obvious regression of the double fold; however, 3 patients required reoperation to correct loosening of the fold on one side during the follow-up period. One patient presented with the suture knot subcutaneously, and the knot was removed in the clinic.Conclusions The modified single-knot continuous buried non-incisional technique is a simple and less time-consuming method for a durable double fold and provides satisfactory aesthetic results.

  7. Room Temperature Operation of a Buried Heterostructure Photonic Crystal Quantum Cascade Laser

    CERN Document Server

    Peretti, R; Wolf, J M; Bonzon, C; Süess, M J; Lourdudoss, S; Metaferia, W; Beck, M; Faist, J

    2015-01-01

    We demonstrated room temperature operation of deep etched photonic crystal quantum cascade laser emitting around 8.5 micron. We fabricated buried heterostructure photonic crystals, resulting in single mode laser emission on a high order slow Bloch modes of the photonic crystal, between high symmetry points of the Brillouin.

  8. Feasibility of fast neutron analysis for the detection of explosives buried in soil

    Energy Technology Data Exchange (ETDEWEB)

    Faust, A.A. [Defence R and D Canada - Suffield, Medicine Hat, Alta. (Canada); McFee, J.E., E-mail: John.McFee@drdc-rddc.gc.ca [Defence R and D Canada - Suffield, Medicine Hat, Alta. (Canada); Bowman, C.L.; Mosquera, C. [Defence R and D Canada - Suffield, Medicine Hat, Alta. (Canada); Andrews, H.R.; Kovaltchouk, V.D.; Ing, H. [Bubble Technology Industries, Chalk River, Ont. (Canada)

    2011-12-11

    A commercialized thermal neutron analysis (TNA) sensor has been developed to confirm the presence of buried bulk explosives as part of a multi-sensor anti-tank landmine detection system. Continuing improvements to the TNA system have included the use of an electronic pulsed neutron generator that offers the possibility of applying fast neutron analysis (FNA) methods to improve the system's detection capability. This paper describes an investigation into the use of FNA as a complementary component in such a TNA system. The results of a modeling study using simple geometries and a full model of the TNA sensor head are presented, as well as preliminary results from an experimental associated particle imaging (API) system that supports the modeling study results. The investigation has concluded that the pulsed beam FNA approach would not improve the detection performance of a TNA system for landmine or buried IED detection in a confirmation role, and could not be made into a practical stand-alone detection system for buried anti-tank landmines. Detection of buried landmines and IEDs by FNA remains a possibility, however, through the use of the API technique.

  9. The diffusion of buried matter and possible pollution of aquifers in presence of hydrodynamic dispersion

    International Nuclear Information System (INIS)

    The problem of diffusion of buried waste in a moist soil is formulated in cylindrical coordinates and solved by means of integral transform techniques after appropriate asymptotic approximations. The model is then used to predict the possible contamination of aquifers situated at a given depth. (author). 2 refs, 2 figs

  10. Remotely controlled vehicles and systems for integrated remediation of buried tru wastes

    International Nuclear Information System (INIS)

    This paper describes the design, implementation and testing of remotely controlled vehicle systems developed for cooperative retrieval and transportation of Transuranic (TRU) buried wastes. The systems described are for the control of a Remote Excavator (REMEX), a Self Guided Transfer Vehicle (SGTV), a Remotely Controlled Materials Handling System and a Virtual Environment for Remote Operations (VERO), using imaging by a 3D Laser Camera

  11. Probing the magnetism of nanostructures buried in metallic surfaces and their possible utilization

    Energy Technology Data Exchange (ETDEWEB)

    Brovko, Oleg O.; Stepanyuk, Valeri S. [Max-Planck-Institut fuer Mikrostrukturphysik, Halle (Germany)

    2010-05-15

    We discuss the possibility to probe magnetic properties of nanostructures buried beneath a metallic surface by means of local probe techniques. We prove, that those properties can be deduced from the spin-resolved local density of states (LDOS) above the surface. In-plane polarization maps in vacuum above the surface are shown to allow one to simultaneously detect electronic, magnetic, and even geometric properties of subsurface structures. It is argued, that the coupling of buried nanostructures to each other can be deduced from the symmetry of the polarization map. To underline the importance of studying buried nanostructures several possible applications of buried magnetic impurities are pointed out. The exchange coupling of an adatom to a nanostructure or a monolayer (ML) across a paramagnetic spacer is shown to oscillate with the thickness of the latter. This could provide one with reliable means to stabilize the spin of a magnetic adatom in either a ferromagnetic or an antiferromagnetic configuration with respect to the magnetic orientation of the monolayer or nanostructure. The possibility to tailor the exchange coupling between single magnetic impurities on a surface through the adjustment of the overlayer thickness and the interatomic separation in a dimer, is discussed. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  12. Influence of Population Density on Offspring Number and Size in Burying Beetles

    Science.gov (United States)

    Rauter, Claudia M.

    2010-01-01

    This laboratory exercise investigates the influence of population density on offspring number and size in burying beetles. Students test the theoretical predictions that brood size declines and offspring size increases when competition over resources becomes stronger with increasing population density. Students design the experiment, collect and…

  13. Evaluating In Situ Treatment Technologies for Buried Mixed Waste Remediation at the INEEL

    Energy Technology Data Exchange (ETDEWEB)

    D.F. Nickelson; D.K. Jorgensen; J.J. Jessmore; R.A. Hyde; R.K. Farnsworth

    1999-02-01

    Mixed radioactive and hazardous wastes were buried at the Department of Energy's Idaho National Engineering and Environmental Laboratory (INEEL) Subsurface Disposal Area from 1952 to 1969. To begin the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remediation process for the Subsurface Disposal Area, the Environmental Protection Agency (EPA) added the INEEL to its National Priorities List in 1989. DOE's Office of Environmental Restoration is planning several CERCLA treatability studies of remedial technologies that will be evaluated for potential remediation of the buried waste in the Subsurface Disposal Area. This paper discusses the in situ treatability studies that will be performed, including in situ vitrification, in situ grouting, and in situ thermal desorption. The in situ treatability studies will be conducted on simulated and actual buried wastes at the INEEL in 1999 and 2000. Results from the treatability studies will provide substantial information on the feasibility, implementability, and cost of applying these technologies to the INEEL Subsurface Disposal Area. In addition, much of the treatability study data will be applicable to buried waste site remediation efforts across the DOE complex.

  14. Evaluating In Situ Treatment Technologies for Buried Mixed Waste Remediation at the INEEL

    Energy Technology Data Exchange (ETDEWEB)

    Jorgensen, Douglas Kay; Nickelson, David Frank; Nickelson, Reva Anne; Farnsworth, Richard Kent; Jessmore, James Joseph

    1999-03-01

    Mixed radioactive and hazardous wastes were buried at the Department of Energy’s Idaho National Engineering and Environmental Laboratory (INEEL) Subsurface Disposal Area from 1952 to 1969. To begin the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remediation process for the Subsurface Disposal Area, the Environmental Protection Agency (EPA) added the INEEL to its National Priorities List in 1989. DOE’s Office of Environmental Restoration is planning several CERCLA treatability studies of remedial technologies that will be evaluated for potential remediation of the buried waste in the Subsurface Disposal Area. This paper discusses the in situ treatability studies that will be performed, including in situ vitrification, in situ grouting, and in situ thermal desorption. The in situ treatability studies will be conducted on simulated and actual buried wastes at the INEEL in 1999 and 2000. Results from the treatability studies will provide substantial information on the feasibility, implementability, and cost of applying these technologies to the INEEL Subsurface Disposal Area. In addition, much of the treatability study data will be applicable to buried waste site remediation efforts across the DOE complex.

  15. Investigation of vegetation history of buried chernozem soils using near-infrared spectroscopy (NIRS)

    Czech Academy of Sciences Publication Activity Database

    Vysloužilová, B.; Ertlen, D.; Šefrna, L.; Novák, T.; Virágh, K.; Rué, M.; Campaner, A.; Dreslerová, Dagmar; Schwartz, D.

    2015-01-01

    Roč. 365, 16 April (2015), s. 203-211. ISSN 1040-6182 Institutional support: RVO:67985912 Keywords : Holocene * paleopedology * paleoecology * near-infrared spectroscopy * chernozem * buried paleosol Subject RIV: DF - Soil Science Impact factor: 2.062, year: 2014

  16. Long-term dynamics of buried organic carbon in colluvial soils

    Directory of Open Access Journals (Sweden)

    Z. Wang

    2013-08-01

    Full Text Available Colluvial soils are enriched in soil organic carbon (SOC in comparison to the soils of upslope areas due to the deposition and subsurface burial of SOC. It has been suggested that the burial of SOC has important implications for the global carbon cycle, but the long-term dynamics of buried SOC remains poorly constrained. We address this issue by determining the SOC burial efficiency (i.e., the fraction of originally deposited SOC that is preserved in colluvial deposits of buried SOC as well as the SOC stability in colluvial soils. We quantify the turnover rate of deposited SOC by establishing sediment and SOC burial chronologies. The SOC stability is derived from soil incubation experiments and the δ13C values of SOC. The C burial efficiency was found to decrease exponentially with time reaching a constant ratio of approximately 17%. This exponential decrease is attributed to the increasing recalcitrance of buried SOC with time and a less favourable environment for SOC decomposition with increasing depth. Buried SOC is found to be more stable and degraded in comparison to SOC sampled at the same depth at a stable site. This is due to preferential mineralization of the labile fraction of deposited SOC resulting in enrichment of more degraded and recalcitrant SOC in colluvial soils. In order to better understand the long-term effects of soil erosion for the global C cycle, the temporal variation of deposited SOC and its controlling factors need to be characterized and quantified.

  17. Proton implanted buried planar and channel waveguides in sapphire and Ti:sapphire

    NARCIS (Netherlands)

    Laversenne, L.; Hoffmann, P.; Pollnau, M.; Moretti, P.

    2004-01-01

    Buried planar and channel waveguides are demonstrated in proton implanted sapphire and Ti:sapphire. The simplicity of the fabrication technique results in a large flexibility for the design of versatile guiding structures. Good control over the implantation parameters provides excellent light confin

  18. GPR Detection of Buried Symmetrically Shaped Mine-like Objects using Selective Independent Component Analysis

    DEFF Research Database (Denmark)

    Karlsen, Brian; Sørensen, Helge Bjarup Dissing; Larsen, Jan;

    2003-01-01

    from small-scale anti-personal (AP) mines to large-scale anti-tank (AT) mines were designed. Large-scale SF-GPR measurements on this series of mine-like objects buried in soil were performed. The SF-GPR data was acquired using a wideband monostatic bow-tie antenna operating in the frequency range 750...

  19. 7 CFR 1755.860 - RUS specification for filled buried wires.

    Science.gov (United States)

    2010-01-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of ANSI/EIA 359-A-84 are available for inspection.... 552(a) and 1 CFR part 51. Copies of the ASTM standards are available for inspection during normal... 7 Agriculture 11 2010-01-01 2010-01-01 false RUS specification for filled buried wires....

  20. Laser-induced acoustic landmine detection with experimental results on buried landmines

    NARCIS (Netherlands)

    Heuvel, J.C. van den; Putten, F.J.M. van; Koersel, A.C. van; Schleijpen, H.M.A.

    2004-01-01

    Acoustic landmine detection (ALD) is a technique for the detection of buried landmines including non-metal mines. Since it gives complementary results with GPR or metal detection, sensor fusion of these techniques with acoustic detection would give promising results. Two methods are used for the aco

  1. Structure of the Buried Metal-Molecule Interface in Organic Thin Film Devices

    DEFF Research Database (Denmark)

    Hansen, Christian Rein; Sørensen, Thomas Just; Glyvradal, Magni; Larsen, Jacob; Eisenhardt, Sara H.; Bjørnholm, Thomas; Nielsen, Martin Meedom; Feidenhans'l, Robert Krarup; Laursen, Bo Wegge

    2009-01-01

    comparison of XR data for the five-layer Pb2+ arachidate LB film before and after vapor deposition of the Ti/Al top electrode, a detailed account of the structural damage to the organic film at the buried metal-molecule interface is obtained. We find that the organized structure of the two topmost LB layers...

  2. Modeling of Buried Wire Detection by Radio-Frequency Electromagnetic Waves

    NARCIS (Netherlands)

    Naus, H.W.L.

    2013-01-01

    The detection of buried insulated wires of finite length with a transmitter–receiver electromagnetic induction sensor is theoretically investigated. The transmitter is modeled as a magnetic dipole. Its electric field induces a current in the cable. Analytical results for its Fourier transform are ca

  3. Groundwater Flow Dynamic Simulations of a Buried Valley Aquifer Calibrated with Field and Remotely Sensed Data

    Science.gov (United States)

    Calderhead, A. I.; Hinton, M. J.; Logan, C. E.; Sharpe, D.; Russel, H. A.; Oldenborger, G. A.; Pugin, A.; Rivera, A.; Castellazzi, P.; Martel, R.

    2013-12-01

    Buried valleys are a common occurrence in the North American prairie landscape. They are often characterized as high yield sources of groundwater in regions where low yield shale and tills dominate the hydrogeological setting. Firstly, 3D conceptual and geological models have been generated and used as a basis for creating a 3D finite element groundwater flow model. Field data, including piezometric readings, base flow measurements, and soil moisture probe data were collected between 2011 and 2013 and are used for calibrating the flow model. Secondly, the study aims to improve the spatial discretization of recharge estimates and include these refined values in the flow model. A temporal series of C-band Radar data and several land surface models were compared with the soil moisture probe data from the Spiritwood buried valley aquifer. The radar backscatter was used to develop moisture estimates at the regional scale. These estimates were then input into the HELP multi-parameter recharge model with the aim of assisting in estimates of a spatial discretization for groundwater recharge. Preliminary groundwater simulation results, with uniform recharge, show good agreement with piezometer readings and measured base flow readings. The temporal series of C-band radar backscatter, moisture probe data, and land surface models show corresponding variations between October, 2011 and October, 2012. The high resolution and regional extent of the radar data has a high potential to help develop a better understanding of recharge patterns in buried valley settings. Integrating a temporal series of high-resolution data into conceptual and numerical model development will refine our mapping, understanding and assessment of buried valley aquifers. Future work will include incorporating the spatially variable recharge estimates into the 3D finite element flow model. Additionally, various interpretations of the geological model will be tested to determine the extent, if any, that a

  4. HDI板塞埋孔微裂纹研究和改善%Research and improvement of the micro-crack of HDI PCB plug buried hole

    Institute of Scientific and Technical Information of China (English)

    张军杰; 刘克敢; 韩启龙

    2013-01-01

    This paper discusses the theory of micro crack around buried holes. Some experiments are designed and executed on such base. According to the experiment results, the process is optimized by inserting bake process between AOI and black oxidation and implement brown process as plugging pre-treatment, and prepreg with high resin content is preferentially recommended;the Tg and Z-CTE of prepreg and ink should be as consistent as possible. If all these measures is taken, the micro crack around buried holes will be under control and the reliability of HDI products will be improved remarkably.%文章在分析塞埋孔微裂纹机理的基础上系统研究了烘板工艺,半固化片树脂含量和不同塞埋孔树脂及塞埋孔前处理工艺等对塞埋孔微裂纹的影响,通过增加黑化前烘板流程、优先选择高树脂含量的半固化片、塞埋孔前采用棕化前处理并优先选择与半固化片Tg和Z-CTE一致性更好的树脂塞埋孔,实现了塞埋孔微裂纹的显著改善,并有效控制了HDI分层风险。

  5. Development of hard x-ray photoelectron SPLEED-based spectrometer applicable for probing of buried magnetic layer valence states

    CERN Document Server

    Kozina, Xeniya; Karel, Julie; Ouardi, Siham; Yamamoto, Masafumi; Kobayashi, Keisuke; Schonhense, Gerd; Fecher, Gerhard H; Felser, Claudia; Ikenaga, Eiji

    2015-01-01

    A novel design of high-voltage compatible polarimeter for spin-resolved hard x-ray photoelectron spectroscopy (Spin-HAXPES) went into operation at beamline BL09XU of SPring-8 in Hyogo, Japan. The detector is based on the well-established principle of electron diffraction from a W(001) single-crystal at a scattering energy of 103.5 eV. Its special feature is that it can be operated at a high negative bias potential up to 10 kV, necessary to access the HAXPES range. The polarimeter is operated behind a large hemispherical analyzer (Scienta R-4000). It was optimized for high transmission of the transfer optics. The exit plane of the analyzer contains a delay-line detector (20 mm dia.) for conventional multichannel intensity spectroscopy simultaneously with single-channel spin analysis. The performance of the combined setup is demonstrated by the first spin-resolved data for the valence-region of a FeCo functional layer of a tunneling device, buried beneath 3 nm of oxidic material. The well-structured spin polari...

  6. A Re-Examination of the Relative Ages of Mare-Filled Impact Basins on the Lunar Nearside from the Gravity Signatures of Buried Craters

    Science.gov (United States)

    Evans, A. J.; Soderblom, J. M.; Solomon, S. C.; Zuber, M. T.

    2015-05-01

    GRAIL gravity data have revealed more than 100 putative buried impact craters beneath the nearside maria. We use this population of buried craters to re-assess basin chronology and the impact crater density of the lunar nearside.

  7. Ultra-low specific on-resistance SOI double-gate trench-type MOSFET

    Science.gov (United States)

    Tianfei, Lei; Xiaorong, Luo; Rui, Ge; Xi, Chen; Yuangang, Wang; Guoliang, Yao; Yongheng, Jiang; Bo, Zhang; Zhaoji, Li

    2011-10-01

    An ultra-low specific on-resistance (Ron, sp) silicon-on-insulator (SOI) double-gate trench-type MOSFET (DG trench MOSFET) is proposed. The MOSFET features double gates and an oxide trench: the oxide trench is in the drift region, one trench gate is inset in the oxide trench and one trench gate is extended into the buried oxide. Firstly, the double gates reduce Ron, sp by forming dual conduction channels. Secondly, the oxide trench not only folds the drift region, but also modulates the electric field, thereby reducing device pitch and increasing the breakdown voltage (BV). ABV of 93 V and a Ron, sp of 51.8 mΩ·mm2 is obtained for a DG trench MOSFET with a 3 μm half-cell pitch. Compared with a single-gate SOI MOSFET (SG MOSFET) and a single-gate SOI MOSFET with an oxide trench (SG trench MOSFET), the Ron, sp of the DG trench MOSFET decreases by 63.3% and 33.8% at the same BV, respectively.

  8. Technology evaluation report for the Buried Waste Robotics Program Subsurface Mapping Project

    International Nuclear Information System (INIS)

    This document presents a summary of the work performed in support of the Buried Waste Robotics Program Subsurface Mapping Project. The project objective was to demonstrate the feasibility of remotely characterizing buried waste sites. To fulfill this objective, a remotely-operated vehicle, equipped with several sensors, was deployed at the Idaho National Engineering Laboratory. Descriptions of the equipment and areas involved in the project are included in this report. Additionally, this document provides data that was obtained during characterization operations at the Cold Test Pit and the Subsurface Disposal Area, both at the Idaho National Engineering Laboratory's Radioactive Waste Management Complex, and at the Idaho Chemical Processing Plant. The knowledge gained from the experience, that can be applied to the next generation remote-characterization system, is extensive and is presented in this report

  9. EXPERIMENTAL AND NUMERICAL INVESTIGATION OF FLEXIBLE BURIED PIPE DEFORMATION BEHAVIOR UNDER VARIOUS BACKFILL CONDITIONS

    Directory of Open Access Journals (Sweden)

    Niyazi Uğur TERZİ

    2009-01-01

    Full Text Available Deformation characteristics of polyethylene based flexible pipes are different than rigid pipes such as concrete and iron pipes. Deflection patterns and stress-strain behaviors of flexible pipes have strict relation between the engineering properties of backfill and its settlement method. In this study, deformation behavior of a 100 mm HDPE flexible pipe under vertical loads is investigated in laboratory conditions. Steel test box, pressurized membrane, raining system, linear position transducers and strain gauge rosettes are used in the laboratory tests. In order to analyze the buried pipe performance; Masada Derivation Formula which is mostly used by designers is employed. According to the test and mathematical studies, it is understood that relative density of backfill and its settlement method is a considerable effect on buried pipe performance and Masada Derivation method is very efficient for predicting the pipe performance.

  10. The kinetics of solid phase epitaxy in As-doped buried amorphous silicon layers

    International Nuclear Information System (INIS)

    The kinetics of dopant-enhanced solid phase epitaxy (SPE) have been measured in buried a-Si layers doped with arsenic. SPE rates were measured over the temperature range 480 - 660 deg C for buried a-Si layers containing ten different As concentrations. In the absence of H-retardation effects, the dopant-enhanced SPE rate is observed to depend linearly on the As concentration over the entire range of concentrations, 1-16 x 1019 cm-3 covered in the study. The Fermi level energy was calculated as a function of doping and find an equation that can provide good fits to the data. The implications of these results for models of the SPE process is discussed

  11. Super analog computer for evaluating the safety of buried radioactive waste

    International Nuclear Information System (INIS)

    It is argued that the past use of digital computer programs for evaluating the safety of buried radioactive waste has been largely wasteful and dangerously delusive. It is suggested to use actual rocks as the analog of buried waste. The problem of comparable rates of leaching of radioactive waste and of natural rock is discussed. Two examples are given of the use of natural rock as an ''analog computer'': one for high-level radioactive waste, and one for low-level radioactive waste. Digital computers have not contributed anything to two crucial questions: Can shafts be securely sealed. Does the heat crack the rock or have important effects on its chemistry. 4 refs

  12. Improved charge collection of the buried p-i-n a-Si:H radiation detectors

    International Nuclear Information System (INIS)

    Charge collection in hydrogenated amorphous silicon (a-Si:H) radiation detectors is improved for high LET particle detection by adding thin intrinsic layers to the usual p-i-n structure. This buried p-i-n structure enables us to apply higher bias and the electric field is enhanced. When irradiated by 5.8 MeV α particles, the 5.7 μm thick buried p-i-n detector with bias 300V gives a signal size of 60,000 electrons, compared to about 20,000 electrons with the simple p-i-n detectors. The improved charge collection in the new structure is discussed. The capability of tailoring the field profile by doping a-Si:H opens a way to some interesting device structures. 17 refs., 7 figs

  13. Reducing Thermal Losses and Gains With Buried and Encapsulated Ducts in Hot-Humid Climates

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C.; Magee, A.; Zoeller, W.

    2013-02-01

    The Consortium for Advanced Residential Buildings (CARB) monitored three houses in Jacksonville, FL, to investigate the effectiveness of encapsulated and encapsulated/buried ducts in reducing thermal losses and gains from ductwork in unconditioned attics. Burying ductwork beneath loose-fill insulation has been identified as an effective method of reducing thermal losses and gains from ductwork in dry climates, but it is not applicable in humid climates where condensation may occur on the outside of the duct jacket. By encapsulating the ductwork in closed cell polyurethane foam (ccSPF) before burial beneath loose-fill mineral fiber insulation, the condensation potential may be reduced while increasing the R-value of the ductwork.

  14. Buried waste remote survey of the Idaho National Engineering Laboratory subsurface disposal area

    International Nuclear Information System (INIS)

    Burial site characterization is an important first step in the restoration of subsurface disposal sites. Testing and demonstration of technology for remote buried waste site characterization were performed at the Idaho National Engineering Laboratory (INEL) by a team from five US Department of Energy (DOE) laboratories. The US Army's Soldier Robot Interface Project (SRIP) vehicle, on loan to the Oak Ridge National Laboratory (ORNL), was used as a remotely operated sensor platform. The SRIP was equipped with an array of sensors including terrain conductivity meter, magnetometer, ground-penetrating radar (GPR), organic vapor detector, gamma-based radar detector, and spectrum analyzer. The testing and demonstration were successfully completed and provided direction for future work in buried waste site characterization

  15. Environment, Safety, Health, and Quality Plan for the Buried Waste Integrated Demonstration Program

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) is a program funded by the US Department of Energy Office of Technology Development. BWID supports the applied research, development, demonstration, testing, and evaluation of a suite of advanced technologies that together form a comprehensive remediation system for the effective and efficient remediation of buried waste. This document describes the Environment, Safety, Health, and Quality requirements for conducting BWID activities at the Idaho National Engineering Laboratory. Topics discussed in this report, as they apply to BWID operations, include Federal, State of Idaho, and Environmental Protection Agency regulations, Health and Safety Plans, Quality Program Plans, Data Quality Objectives, and training and job hazard analysis. Finally, a discussion is given on CERCLA criteria and System and Performance audits as they apply to the BWID Program

  16. Buried waste integrated demonstration Fiscal Year 1993 close-out report

    International Nuclear Information System (INIS)

    The Buried Waste Integrated Demonstration (BWID) supports the applied research, development, demonstration, and evaluation of a multitude of advanced technologies. These technologies are being integrated to form a comprehensive remediation system for the effective and efficient remediation of buried waste. These efforts are identified and coordinated in support of the U.S. Department of Energy Environmental Restoration and Waste Management needs and objectives. BWID works with universities and private industry to develop these technologies, which are being transferred to the private sector for use nationally and internationally. A public participation policy has been established to provide stakeholders with timely and accurate information and meaningful opportunities for involvement in the technology development and demonstration process. To accomplish this mission of identifying technological solutions for remediation deficiencies, the Office of Technology Development initiated BWID at the Idaho National Engineering Laboratory. This report summarizes the activities of the BWID program during FY-93

  17. Comparison of nerve graft integration after segmentar resection versus epineural burying in crushed rat sciatic nerves

    Directory of Open Access Journals (Sweden)

    Cunha Marco Túlio Rodrigues da

    1997-01-01

    Full Text Available The aim of the present paper is to compare and correlate the take of nerve segments in a severely crushed nerve. Forty adult Wistar rats had their right sciatic nerve by a "Péan-Murphy" forceps for 40 minutes. In Group 1 (n=20, a segmentar serection in the crushed sciatic nerve was made. A sural nerve segment from the opposite hindpaw was placed in the gap. In Group 2 (n=20, a lontudinal insision in the epineurium of the lesioned sciatic nerve was made. A sural nerve segment was buried underneath the epineurium. The crushed sciatic nerves undergone Wallerian degeneration and endoneurial fibrosis. Sciatic nerves from Group 2 had significant better histological aspects than those from Group 1. Sural nerve grafts presented better degrees of regeneration than crushed sciatic nerves. Sural nerve grafts from Group 2 (burying method integrated as well as those from Group 1 (segmentar resection.

  18. Stepped-Frequency Ground-Penetrating Radar for Detection of Small Non-metallic Buried Objects

    DEFF Research Database (Denmark)

    Jakobsen, Kaj Bjarne; Sørensen, Helge Bjarup Dissing; Nymann, Ole

    1997-01-01

    A monostatic amplitude and phase stepped-frequency radar approach have been proposed to detect small non-metallic buried anti-personnel (AP) mines. An M-56 AP-mine with a diameter of 54 mm and height of 40 mm, only, has been successfully detected and located in addition to small metallic mine...... each measurement point using a mesh-grid with a resolution down to 1 mm by 1 mm. The size of the scan area is 1410 mm by 210 mm. Measurements have been performed on loamy soil containing a buried M-56, a non-metallic AP-mine, and various other mine-like objects made of solid plastic, brass, aluminum...

  19. Coherent phonon spectroscopy characterization of electronic bands at buried semiconductor heterointerfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ishioka, Kunie, E-mail: ishioka.kunie@nims.go.jp [Nano Characterization Unit, National Institute for Materials Science, Tsukuba 305-0047 (Japan); Brixius, Kristina; Beyer, Andreas; Stolz, Wolfgang; Volz, Kerstin; Höfer, Ulrich [Faculty of Physics and Materials Sciences Center, Philipps-Universität Marburg, 35032 Marburg (Germany); Rustagi, Avinash; Stanton, Christopher J. [Department of Physics, University of Florida, Gainesville, Florida 32611 (United States); Petek, Hrvoje [Department of Physics and Astronomy and Pittsburgh Quantum Institute, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States)

    2016-02-01

    We demonstrate an all-optical approach to probe electronic band structure at buried interfaces involving polar semiconductors. Femtosecond optical pulses excite coherent phonons in epitaxial GaP films grown on Si(001) substrate. We find that the coherent phonon amplitude critically depends on the film growth conditions, specifically in the presence of antiphase domains, which are independently characterized by transmission electron microscopy. We determine the Fermi levels at the buried interface of GaP/Si from the coherent phonon amplitudes and demonstrate that the internal electric fields are created in the nominally undoped GaP films as well as the Si substrates, possibly due to the carrier trapping at the antiphase boundaries and/or at the interface.

  20. Non-destructive imaging of buried electronic interfaces using a decelerated scanning electron beam.

    Science.gov (United States)

    Hirohata, Atsufumi; Yamamoto, Yasuaki; Murphy, Benedict A; Vick, Andrew J

    2016-01-01

    Recent progress in nanotechnology enables the production of atomically abrupt interfaces in multilayered junctions, allowing for an increase in the number of transistors in a processor. However, uniform electron transport has not yet been achieved across the entire interfacial area in junctions due to the existence of local defects, causing local heating and reduction in transport efficiency. To date, junction uniformity has been predominantly assessed by cross-sectional transmission electron microscopy, which requires slicing and milling processes that can potentially introduce additional damage and deformation. It is therefore essential to develop an alternative non-destructive method. Here we show a non-destructive technique using scanning electron microscopy to map buried junction properties. By controlling the electron-beam energy, we demonstrate the contrast imaging of local junction resistances at a controlled depth. This technique can be applied to any buried junctions, from conventional semiconductor and metal devices to organic devices. PMID:27586090