WorldWideScience

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. 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.

  4. Optimizing Design of Breakdown Voltage to Eliminate Back Gate Bias Effect in Silicon-on-Insulator Diode Using Low Doping Buried Layer

    Institute of Scientific and Technical Information of China (English)

    H0 Chi-Hon; LIAO Chen-Nan; CHIEN Feng-Tso; TSAI Yao-Tsung

    2009-01-01

    This work presents the optimal design of a silicon-on-insulator (SOI) diode structure to eliminate the back gate bias effect and to improve breakdown voltage. The SOI structure is characterized by inserting a silicon low doping buried layer (LDBL) between the silicon layer and the buried oxide layer. The LDBL thickness is a key parameter that affects the strong inversion condition of the back MOS capacitor of the new SOI diode. The optimal LDBL thickness in the SOI diode is 2.65μm. The LDBL shielding layer improved the breakdown voltage.

  5. 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

  6. A Novel Fully Depleted Air AlN Silicon-on-Insulator Metal-Oxide-Semiconductor Field Effect Transistor

    Institute of Scientific and Technical Information of China (English)

    YANG Yuan; GAO Yong; GONG Peng-Liang

    2008-01-01

    @@ A novel fully depleted air AlN silicon-on-insulator (SOI) metal-oxide-semiconductor field effect transistor (MOS-FET) is presented, which can eliminate the self-heating effect and solve the problem that the off-state current of SOI MOSFETs increases and the threshold voltage characteristics become worse when employing a high thermal conductivity material as a buried layer. The simulation results reveal that the lattice temperature in normal SOI devices is 75K higher than the atmosphere temperature, while the lattice temperature is just 4K higher than the atmosphere temperature resulting in less severe self-heating effect in air AlN SOI MOSFETs and AlN SOI MOSFETs. The on-state current of air AlN SOI MOSFETs is similar to the AlN SOI structure, and improves 12.3% more than that of normal SOI MOSFETs. The off-state current of AlN SOI is 6.7 times of normal SOI MOSFETs, while the counterpart of air AlN SOI MOSFETs is lower than that of SOI MOSFETs by two orders of magnitude. The threshold voltage change of air AlN SOI MOSFETs with different drain voltage is much less than that of AlN SOI devices, when the drain voltage is biased at 0.8 V, this difference is 28mV, so the threshold voltage change induced by employing high thermal conductivity material is cured.

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

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Ou, Haiyan;

    2010-01-01

    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 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...

  12. Design of a compact waveguide optical isolator based on multimode interferometers using magneto-optical oxide thin films grown on silicon-on-insulator substrates.

    Science.gov (United States)

    Shui, Keyi; Nie, Lixia; Zhang, Yan; Peng, Bo; Xie, Jianliang; Deng, Longjiang; Bi, Lei

    2016-06-13

    We report the design of a waveguide optical isolator based on multimode interferometer (MMI) structure using silicon on insulator (SOI) and deposited magneto-optical (MO) thin films. The optical isolator is based on a vertical 1 × 2 SOI MMI utilizing the nonreciprocal phase shift (NRPS) difference of different TM modes of the MO garnet thin film/SOI waveguide. By constructing a silicon/MO thin film/silicon structure, we demonstrate that the NRPS of the fundamental and first order TM modes can show opposite signs for certain device dimensions, therefore significantly reduce the device length. For a 310.42 μm long device, 20 dB isolation bandwidth larger than 1.6 nm with total insertion loss of 0.817 dB is achieved at 1550 nm wavelength. The fabrication tolerances and materials losses are also discussed to satisfy the state-of-the-art fabrication technology and material properties. PMID:27410305

  13. 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.

  14. 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.

  15. 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...

  16. 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.

  17. 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.

  18. 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.

  19. A high-voltage SOI MOSFET with a compensation layer on the trenched buried oxide layer

    Institute of Scientific and Technical Information of China (English)

    Zhao Qiuming; Li Qi; Tang Ning; Li Yongchang

    2013-01-01

    A new silicon-on-insulator (SOl) high-voltage MOSFET structure with a compensation layer on the trenched buried oxide layer (CL T-LDMOS) is proposed.The high density inverse interface charges at the top surface of the buried oxide layer (BOX) enhance the electric field in the BOX and a uniform surface electric field profile is obtained,which results in the enhancement of the breakdown voltage (BV).The compensation layer can provide additional P-type charges,and the optimal drift region concentration is increased in order to satisfy the reduced surface electric field (RESURF) condition.The numerical simulation results indicate that the vertical electric field in the BOX increases to 6 MV/cm and the BV of the proposed device increases by 300% in comparison to a conventional SOI LDMOS,while maintaining low on-resistance.

  20. 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

  1. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Schwank, J.R.

    1996-09-01

    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.

  3. 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.

  4. Silicon-on-Insulator-Based Waveguide Switch with Fast Response

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuan-Yuan; LI Yun-Tao; XIA Jin-Song; LIU Jing-Wei; CHEN Shao-Wu; YU Jin-Zhong

    2005-01-01

    @@ Based on thermo-optical effect of silicon, a 2 × 2 switch is fabricated in silicon-on-insulator by chemical etching.The switch presents an extinction ratio of 26dB and a power consumption of 169mW. The response time is ~ 10.5μs.

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

    DEFF Research Database (Denmark)

    Liao, Shasha; Ding, Yunhong; Peucheret, Christophe;

    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...

  6. 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.

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. 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 .

  12. 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

  13. 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.

  14. A NEW STRUCTURE AND ITS ANALYTICAL BREAKDOWN MODEL OF HIGH VOLTAGE SOI DEVICE WITH STEP UNMOVABLE SURFACE CHARGES OF BURIED OXIDE LAYER

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new SOI (Silicon On Insulator) high voltage device with Step Unmovable Surface Charges(SUSC) of buried oxide layer and its analytical breakdown model are proposed in the paper. The unmovable charges are implemented into the upper surface of buried oxide layer to increase the vertical electric field and uniform the lateral one. The 2-D Poisson's equation is solved to demonstrate the modulation effect of the immobile interface charges and analyze the electric field and breakdown voltage with the various geometric parameters and step numbers. A new RESURF (REduce SURface Field) condition of the SOI device considering the interface charges and buried oxide is derived to maximize breakdown voltage. The analytical results are in good agreement with the numerical analysis obtained by the 2-D semiconductor devices simulator MEDICI. As a result, an 1200V breakdown voltage is firstly obtained in 3μm-thick top Si layer, 2μm-thick buried oxide layer and 70μm-length drift region using a linear doping profile of unmovable buried oxide charges.

  15. 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.

  16. 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.

  17. 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.

  18. 总剂量效应致0.13µm部分耗尽绝缘体上硅N型金属氧化物半导体场效应晶体管热载流子增强效应∗%Enhanced channel hot carrier effect of 0.13 µm silicon-on-insulator N metal-oxide-semiconductor field-effect transistor induced by total ionizing dose effect

    Institute of Scientific and Technical Information of China (English)

    周航; 郑齐文; 崔江维; 余学峰; 郭旗; 任迪远; 余德昭; 苏丹丹

    2016-01-01

    In this paper, a series of hot carriers tests of irradiated 130 nm partially depleted silicon-on-insulator NMOSFETs is carried out in order to explore the HCI influence on the ionizing radiation damage. Some devices are irradiated by up to 3000 Gy before testing the hot carriers, while other devices experience hot carriers test only. All the devices we used in the experiments are fabricated by using a 130 nm partially depleted (PD) SOI technology. The devices each have a 6 nm-thick gate oxide, 100 nm-thick silicon film, and 145 nm-thick buried oxide, with using shallow trench isolation (STI) for isolation scheme. The irradiation experiments are carried by 60Co-γ ray at the Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, with a dose rate of 0.8 Gy(Si)/s. During irradiation all the samples are biased at 3.3 V, i.e., VGS =3.3 V and other pins are grounded, and when the devices are irradiated respectively by total doses of 500, 1000, 2000 and 3000 Gy(Si), we test the characteristic curves again. Then 168-hour room temperature anneal experiments are carried out for the irradiated devices, using the same biases under irradiation. The HCI stress condition is chosen by searching for the maximum substrate current. The cumulative stress time is 5000 s, and the time intervals are 10, 100, 500, 1000 and 5000 s respectively. After each stress interval, the device parameters are measured until stress time termination appears. Through the comparison of characteristic between pre-irradiated and unirradiated devices, we find that the total dose damage results in the enhanced effect of hot carriers: the substrate current value which characterizes the hot carrier effect (for SOI device are the body to the ground current) increases with the increase of total dose, as the pre-irradiated and unirradiated device do under the same conditions of hot carrier stress, the degradations of key electrical parameters are more obvious for the pre-irradiated one

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

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Xue, Weiqi;

    2010-01-01

    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....

  20. 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.

  1. 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....

  2. 360° tunable microwave phase shifter based on silicon-on-insulator dual-microring resonator

    DEFF Research Database (Denmark)

    Pu, Minhao; Xue, Weiqi; Liu, Liu;

    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...

  3. Interface trap density evaluation on bare silicon-on-insulator wafers using the quasi-static capacitance technique

    Science.gov (United States)

    Pirro, L.; Ionica, I.; Ghibaudo, G.; Mescot, X.; Faraone, L.; Cristoloveanu, S.

    2016-05-01

    This paper presents a detailed investigation of the quasi-static capacitance-voltage (QSCV) technique in pseudo-metal-oxide-semiconductor field effect transistor (pseudo-MOSFET) configuration for evaluating the interface quality of bare silicon-on-insulator (SOI) wafers, without processing dedicated metal-oxide-semiconductor (MOS) test devices. A physical model is developed that is capable of explaining the experimental results. In addition, frequency effects are used to validate the equations by a systematic comparison between experimental and calculated characteristics, as well as by a direct comparison with the standard high-low frequency approach. An extraction procedure for interface trap density based solely on QSCV experimental results is proposed, and limits of the procedure are discussed. The proposed experimental and analytical procedure is demonstrated by characterizing SOI structures with different geometries and with different qualities of surface passivation of the top silicon film.

  4. 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.

  5. 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

  6. Ultra-low loss nano-taper coupler for Silicon-on-Insulator ridge waveguide

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Ou, Haiyan;

    2010-01-01

    A nano-taper coupler is optimized specially for the transverse-magnetic mode for interfacing light between a silicon-on-insulator ridge waveguide and a single-mode fiber. An ultra-low coupling loss of ~0.36dB is achieved for the nano-taper coupler....

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

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Xue, Weiqi;

    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...

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

    DEFF Research Database (Denmark)

    Pu, Minhao; Liu, Liu; Xue, Weiqi;

    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...

  9. 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

  10. Effect of cryogenic temperature characteristics on 0.18-μm silicon-on-insulator devices

    Science.gov (United States)

    Bingqing, Xie; Bo, Li; Jinshun, Bi; Jianhui, Bu; Chi, Wu; Binhong, Li; Zhengsheng, Han; Jiajun, Luo

    2016-07-01

    The experimental results of the cryogenic temperature characteristics on 0.18-μm silicon-on-insulator (SOI) metal-oxide-silicon (MOS) field-effect-transistors (FETs) were presented in detail. The current and capacitance characteristics for different operating conditions ranging from 300 K to 10 K were discussed. SOI MOSFETs at cryogenic temperature exhibit improved performance, as expected. Nevertheless, operation at cryogenic temperature also demonstrates abnormal behaviors, such as the impurity freeze-out and series resistance effects. In this paper, the critical parameters of the devices were extracted with a specific method from 300 K to 10 K. Accordingly, some temperature-dependent-parameter models were created to improve fitting precision at cryogenic temperature. Project supported by the National Natural Science Foundation of China (Grant Nos. 61176095 and 61404169) and the Youth Innovation Promotion Association of Chinese Academy of Sciences.

  11. 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...

  12. Analysis of Temperature Dependence of Silicon-on-Insulator Thermo-Optic Attenuator

    Institute of Scientific and Technical Information of China (English)

    LI Yun-Tao; YU Jin-Zhong; CHEN Yuan-Yuan; SUN Fei; CHEN Shao-Wu

    2007-01-01

    The temperature dependence of silicon-on-insulator thermo-optic attenuators is analysed, which originates from the temperature dependence of characteristics of multimode interference. The attenuator depth and power consumption are independent of temperature while the insertion loss depends on the temperature heavily. The variation of the insertion loss decreases from 4.3 dB to 1 dB as the temperature increases from 273 K to 343 K.

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. Patterning of graphene on silicon-on-insulator waveguides through laser ablation and plasma etching

    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

    2016-05-01

    We present the use of femtosecond laser ablation for the removal of monolayer graphene from silicon-on-insulator (SOI) waveguides, and the use of oxygen plasma etching through a metal mask to peel off graphene from the grating couplers attached to the waveguides. Through Raman spectroscopy and atomic force microscopy, we show 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. This loss contribution is measured to be 0.132 dB/μm.

  19. Analysis and Simulation of S-shaped Waveguide in Silicon-on-insulator

    Institute of Scientific and Technical Information of China (English)

    WANG Zhang-tao; FAN Zhong-cao; XIA Jin-song; CHEN Shao-wu; Yu Jinzhong

    2004-01-01

    The simulation and analysis of S-shaped waveguide bend are presented.Bend radius larger than 30 mm assures less than 0.5 dB radiation loss for a 4-μm-wide silicon-on-insulator waveguide bend with 2-μm etch depth.Intersection angle greater than 20° provides negligible crosstalk (<-30 dB) and very low insertion loss.Any reduction in bend radius and intersection angle is at the cost of the degradation of characteristics of bent waveguide and intersecting waveguide, respectively.

  20. High-speed electrooptical VOA integrated in silicon-on-insulator

    Institute of Scientific and Technical Information of China (English)

    Qingfeng Yan(严清峰); Jinzhong Yu(余金中); Jinsong Xia(夏金松); Zhongli Liu(刘忠立)

    2003-01-01

    In this paper, we present simulation results of an electrooptical variable optical attenuator (VOA) inte-grated in silicon-on-insulator waveguide. The device is functionally based on free carriers absorption toachieve attenuation. Beam propagation method (BPM) and two-dimensional semiconductor device simu-lation tool PISCES-Ⅱ were used to analyze the dc and transient characteristics of the device. The devicehas a response time (including rise time and fall time) less than 200 ns, much faster than the thermoopticand micro-electromechanical systems (MEMSs) based VOAs.

  1. A 4 × 4 Strictly Nonblocking Silicon-on-Insulator Thermo-Optic Switch Matrix

    Institute of Scientific and Technical Information of China (English)

    YANG Di; LI Yan-Ping; CHEN Shao-Wu; YU Jin-Zhong

    2005-01-01

    @@ A 4 × 4 strictly nonblocking thermo-optic switch matrix implemented with a 2 × 2 Mach-Zehnder switch unit was fabricated in silicon-on-insulator wafer. Insertion losses of the shortest and the longest path in the device are about 14.8dB and 19.2dB, respectively. The device presents a very low loss dependent on wavelength. For one switch unit, the power consumption needed for operation is measured to be 0.270 W-0.288 W and the switching time is about 13 ± 1μs.

  2. 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.

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

    Science.gov (United States)

    Sarabalis, Christopher J.; Hill, Jeff T.; Safavi-Naeini, Amir H.

    2016-10-01

    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 W-1m-1 for backward and forward Brillouin scattering, respectively.

  4. 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.

  5. 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.

  6. 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 ...

  7. 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

  8. Structure Dependence of Mode Edges in Photonic Crystal Waveguide with Silicon on Insulator

    Institute of Scientific and Technical Information of China (English)

    TANG Hai-Xia; ZUO Yu-Hua; YU Jin-Zhong; WANG Qi-Ming

    2006-01-01

    @@ The mode edges of photonic crystal waveguide with triangular lattice based on a silicon-on-insulator slab are investigated by combination of the effective index method and the two-dimensional plane wave expansion method.The variations of waveguide-mode edges with the structure parameters of photonic crystal are deduced. When the ratio of the radius of air holes to the lattice constant, r/Λ, is fixed and the lattice constant of photonic crystal,Λ, increases, the waveguide-mode edges shift to longer wavelengths. When Λ is fixed and r/Λ increases, the waveguide-mode edges shift to shorter wavelengths. Additionally, when r/Λ and Λ are both fixed, the radius of the two-row air holes adjacent to the waveguide increases, the waveguide-mode edges shift to shorter wavelengths.

  9. 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.

  10. Thermo-optic Goos-Hänchen effect in silicon-on-insulator waveguide

    Science.gov (United States)

    Tang, Tingting; Luo, Li; Liu, Wenli; He, Xiujun; Zhang, Yanfen

    2015-09-01

    We study the thermo-optic Goos-Hänchen (TOGH) effect in a prism-waveguide coupling structure with silicon-on-insulator waveguide. Stationary-phase method is utilized to calculate the TOGH shift. When the waveguide is regarded as a two-dimensional planar waveguide, a nonlinear relation between GH shift and temperature is obtained. Based on the noticeable TOGH effect, a sensitive temperature modulator or sensor can be realized. As the waveguide width is limited, the proposed structure can be regarded as a three-dimensional rectangular waveguide. We explore the GH shift and TOGH effect for different modes propagating in rectangular waveguide which show different linear relations between GH shift and temperature, which can be used to design mode-selective device based on TO effect.

  11. Design and simulation of blue/violet sensitive photodetectors in silicon-on-insulator

    Institute of Scientific and Technical Information of China (English)

    Han Zhitao; Chu Jinkui; Meng Fantao; Jin Rencheng

    2009-01-01

    According to Lambert's law, a novel structure of photodetectors, namely photodetectors in silicon on-insulator, is proposed. By choosing a certain thickness value for the SOI layer, the photodetector can absorb blue/violet light effectively and affect the responsivity of the long wavelength in the visible and near-infrared re gion, making a blue/violet filter unnecessary. The material of the SOI layer is high-resistivity floating-zone silicon which can cause the neutral N type SOI layer to become fully depleted after doping with a P type impurity. This can improve the collection efficiency of short-wavelength photogenerated carriers. The device structure was optimized through numerical simulation, and the results show that the photodiode is a kind of high performance photodetector in the blue/violet region.

  12. Optical functions of silicon from reflectance and ellipsometry on silicon-on-insulator and homoepitaxial samples

    Energy Technology Data Exchange (ETDEWEB)

    Humlíček, J., E-mail: humlicek@physics.muni.cz [CEITEC, Masaryk University, Kamenice 753/5, 62500 Brno (Czech Republic); Šik, J. [ON Semiconductor, 1. máje 2230, 75661 Rožnov p. Radhoštěm (Czech Republic)

    2015-11-21

    The optical properties of silicon have been determined from 0.2 to 6.5 eV at room temperature, using reflectance spectra of silicon-on-insulator (SOI) and ellipsometric spectra of homoepitaxial samples. Optimized Fabry-Perot-type SOI resonators exhibit high finesse even in near ultraviolet. Very high precision values of the real part of the refractive index are obtained in infrared up to a photon energy of 1.3 eV. The spectra of the extinction coefficient, based on observations of light attenuation, extend to 3.2 eV due to measurements on SOI layers as thin as 87 nm. These results allowed us to correct spectroellipsometric data on homoepitaxial samples for the presence of reduced and stabilized surface layers.

  13. Astable Oscillator Circuits using Silicon-on-Insulator Timer Chip for Wide Range Temperature Sensing

    Science.gov (United States)

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

    2008-01-01

    Two astable oscillator circuits were constructed using a new silicon-on-insulator (SOI) 555 timer chip for potential use as a temperature sensor in harsh environments encompassing jet engine and space mission applications. The two circuits, which differed slightly in configuration, were evaluated between -190 and 200 C. The output of each circuit was made to produce a stream of rectangular pulses whose frequency was proportional to the sensed temperature. The preliminary results indicated that both circuits performed relatively well over the entire test temperature range. In addition, after the circuits were subjected to limited thermal cycling over the temperature range of -190 to 200 C, the performance of either circuit did not experience any significant change.

  14. 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.

  15. 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.

  16. 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)

  17. 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.

  18. A comparison of the kink effect in polysilicon thin film transistors and silicon on insulator transistors

    Science.gov (United States)

    Armstrong, G. A.; Brotherton, S. D.; Ayres, J. R.

    1996-09-01

    Polysilicon thin film transistors (TFTs) differ from conventional silicon on insulator (SOI) transistors in that the TFT exhibits a fundamental gate length dependence of the voltage at which a kink occurs in the output characteristics. This difference is shown to be caused by the peak lateral electric field being strongly dependent on the doping density in an SOI transistor, but relatively insensitive to trap distribution in a TFT. Source barrier lowering which occurs in SOI transistors is absent in a TFT, where the increase in current is the result of a field redistribution along the channel. For very short gate lengths, the TFT exhibits a small pseudo-bipolar gain. Estimates of this bipolar gain can be made by simulation of TFT characteristics with and without impact ionisation. The magnitude of the gain is shown to be approximately inversely proportional to gate length.

  19. 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.

  20. 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...

  1. Characterization of the influence of strain on the optical properties of waveguides and microresonators in silicon-on-insulator technology

    NARCIS (Netherlands)

    Westerveld, W.J.; Harmsma, P.J.; Schmits, R.; Tabak, E.; Pozo Torres, J.M.; Urbach, H.P.; Yousefi, M.

    2011-01-01

    Silicon-on-insulator (SOI) technology has become one of the focus platforms for photonic integrated circuits (PICs). The CMOS technology opens the possibility for reliable mass fabrication of cost-effective photonic circuits. Recently there has been a growing interest in direct optical sensing of, f

  2. 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).

  3. 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

  4. 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.

  5. 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.

  6. 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.

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

    Institute of Scientific and Technical Information of China (English)

    Hu Sheng-Dong; Zhang Bo; Li Zhao-Ji

    2009-01-01

    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 30 V/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 2 μm 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.

  8. 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

  9. 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)

  10. 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.

  11. 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.

  12. 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...

  13. 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

  14. A Silicon-on-Insulator-Based Thermo-Optic Waveguide Switch with Low Insertion Loss and Fast Response

    Institute of Scientific and Technical Information of China (English)

    LI Yan-Ping; YU Jin-Zhong; CHEN Shao-Wu

    2005-01-01

    @@ A silicon-on-insulator-based thermo-optic waveguide switch integrated with spot size converters is designed and fabricated by inductively coupled plasma reactive ion etching. The device shows good characteristics, including low insertion loss of 8 ± 1 dB for wavelength 1530-1580nm and fast response times of 4.6 μs for rising edge and 1.9μs for falling edge. The extinction ratios of the two channels are 19.1 and 18 dB, respectively.

  15. 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.

  16. 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.

  17. 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...

  18. High Speed Signal Wavelength Conversion Using Stimulated Raman Effect in Ultrasmall Silicon-on-Insulator Optical Waveguides

    Institute of Scientific and Technical Information of China (English)

    WU Jian-Wei; LUO Feng-Guang; GALLEP Cristiano de Mello

    2008-01-01

    We propose the high speed signal wavelength conversion based on stimulated Raman effect on silicon waveguides.Simulation results of non-return-to-zero(NRZ)pseudorandom bit sequence(27-1 code)at 500-Gb/s rate of conversion in an ultrasmall silicon-on-insulator(SOI)optical wavegnide are presented by co-propagating pump optical field.The most attractive issue is that the inverted converted signal can be obtained at the same wavelength as that of primary signal.In addition,the conversion performances,including extinction ratio(ER)and average peak power of conversion signal,depend strongly on the launching pump intensity.

  19. 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.

  20. 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.

  1. Formation of silicon-on-insulator layer with midair cavity for meniscus force-mediated layer transfer and high-performance transistor fabrication on glass

    Science.gov (United States)

    Akazawa, Muneki; Sakaike, Kohei; Higashi, Seiichiro

    2015-08-01

    We attempted to transfer a phosphorus ion (P+)-implanted oxidized silicon-on-insulator (SOI) layer with a midair cavity to a glass substrate using meniscus force at a low temperature. The SiO2 column size was controlled by etching time and the minimum column size was 104 nm. The transfer yield of the implanted sample was significantly improved by decreasing the column size, and the maximum transfer yield was 95% when the implantation dose was 1 × 1015 cm-2. The causes of increasing transfer yield are considered to be the tapered SiO2 column shape and the hydrophilicity of the surface of oxidized samples with implantation. N-channel thin-film transistors (TFTs) fabricated using the films on glass at 300 °C showed a field-effect mobility of 505 cm2 V-1 s-1, a threshold voltage of 2.47 V and a subthreshold swing of 324 mV/dec. on average.

  2. 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 ...

  3. 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.

  4. Heteroepitaxial growth of Ge on compliant strained nano-structured Si lines and dots on (001) silicon on insulator substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zaumseil, Peter, E-mail: zaumseil@ihp-microelectronics.com [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Yamamoto, Yuji; Schubert, Markus Andreas [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Schroeder, Thomas [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Brandenburgische Technische Universität Cottbus, Konrad-Zuse-Str.1, Cottbus, 03046 (Germany); Tillack, Bernd [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Technische Universität Berlin, HFT4, Einsteinufer 25, 10587 Berlin (Germany)

    2014-04-30

    On the way to integrate lattice mismatched semiconductors on Si(001) we studied the Ge/Si heterosystem with the aim of a misfit dislocation free deposition that offers the vision to integrate defect-free alternative semiconductor structures on Si. Periodic Ge nano-structures (dots and lines) were selectively grown by chemical vapor deposition on Si nano-islands on silicon on insulator substrate with a thin (about 10 nm) SiGe buffer layer between Si and Ge. The strain state of the structures was measured by grazing incidence and specular diffraction using laboratory-based X-ray diffraction technique. The SiGe improves the compliance of the Si compared to direct Ge deposition, prevents plastic relaxation during growth, and allows elastic relaxation before Ge is deposited on top. As a result, an epitaxial growth of Ge on Si fully free of misfit dislocations was achieved. - Highlights: • Realization of nano-structured Si islands (dots and lines) on silicon on insulator substrate • Selective Ge epitaxy on nano-structured periodic Si islands with thin SiGe buffer • Strain characterization of Ge nano-structures by X-ray diffraction • Ge heteroepitaxy on Si without misfit dislocation confirmed by transmission electron microscopy.

  5. Gate direct-tunnelling and hot-carrier-induced hysteresis effect in partially depleted silicon-on-insulator floating-body MOSFETs

    Science.gov (United States)

    Zhou, Jianhua; Pang, Albert; Zou, Shichang

    2011-02-01

    The hysteresis effect in the output characteristics of partially depleted (PD) silicon-on-insulator (SOI) floating-body MOSFETs with an ultra-thin gate oxide is studied taking account of both gate direct-tunnelling and impact ionization-induced hot-carrier mechanisms. It is proposed that hole tunnelling from valence band (HVB) for floating-body PD SOI n-MOSFETs, electron tunnelling from conduction band (ECB) for floating-body PD SOI p-MOSFETs and impact-ionization-induced hot carriers are the main causes of the hysteresis effect. Meanwhile, body-contact structures of T-gate and H-gate PD SOI MOSFETs are also studied under floating-body configurations. It is found that the influence of the converse poly-gate on the body-contact side on gate direct-tunnelling cannot be neglected in view of floating-body potential variation. Based on the measurement results, the hysteresis can be suppressed using T-gate and H-gate PD SOI MOSFETs with floating-body configurations.

  6. Gate direct-tunnelling and hot-carrier-induced hysteresis effect in partially depleted silicon-on-insulator floating-body MOSFETs

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Jianhua; Pang, Albert; Zou Shichang, E-mail: jianhua.zhou@gracesemi.com, E-mail: Albert.Pang@gracesemi.com, E-mail: SC.Zou@gracesemi.com [Grace Semiconductor Manufacturing Corporation, Shanghai 201203 (China)

    2011-02-23

    The hysteresis effect in the output characteristics of partially depleted (PD) silicon-on-insulator (SOI) floating-body MOSFETs with an ultra-thin gate oxide is studied taking account of both gate direct-tunnelling and impact ionization-induced hot-carrier mechanisms. It is proposed that hole tunnelling from valence band (HVB) for floating-body PD SOI n-MOSFETs, electron tunnelling from conduction band (ECB) for floating-body PD SOI p-MOSFETs and impact-ionization-induced hot carriers are the main causes of the hysteresis effect. Meanwhile, body-contact structures of T-gate and H-gate PD SOI MOSFETs are also studied under floating-body configurations. It is found that the influence of the converse poly-gate on the body-contact side on gate direct-tunnelling cannot be neglected in view of floating-body potential variation. Based on the measurement results, the hysteresis can be suppressed using T-gate and H-gate PD SOI MOSFETs with floating-body configurations.

  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. Silicon-on-insulator-based high-voltage, high-temperature integrated circuit gate driver for silicon carbide-based power field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, Leon M [ORNL; Huque, Mohammad A [ORNL; Blalock, Benjamin J [ORNL; Islam, Syed K [ORNL

    2010-01-01

    Silicon carbide (SiC)-based field effect transistors (FETs) are gaining popularity as switching elements in power electronic circuits designed for high-temperature environments like hybrid electric vehicle, aircraft, well logging, geothermal power generation etc. Like any other power switches, SiC-based power devices also need gate driver circuits to interface them with the logic units. The placement of the gate driver circuit next to the power switch is optimal for minimising system complexity. Successful operation of the gate driver circuit in a harsh environment, especially with minimal or no heat sink and without liquid cooling, can increase the power-to-volume ratio as well as the power-to-weight ratio for power conversion modules such as a DC-DC converter, inverter etc. A silicon-on-insulator (SOI)-based high-voltage, high-temperature integrated circuit (IC) gate driver for SiC power FETs has been designed and fabricated using a commercially available 0.8--m, 2-poly and 3-metal bipolar-complementary metal oxide semiconductor (CMOS)-double diffused metal oxide semiconductor (DMOS) process. The prototype circuit-s maximum gate drive supply can be 40-V with peak 2.3-A sourcing/sinking current driving capability. Owing to the wide driving range, this gate driver IC can be used to drive a wide variety of SiC FET switches (both normally OFF metal oxide semiconductor field effect transistor (MOSFET) and normally ON junction field effect transistor (JFET)). The switching frequency is 20-kHz and the duty cycle can be varied from 0 to 100-. The circuit has been successfully tested with SiC power MOSFETs and JFETs without any heat sink and cooling mechanism. During these tests, SiC switches were kept at room temperature and ambient temperature of the driver circuit was increased to 200-C. The circuit underwent numerous temperature cycles with negligible performance degradation.

  10. Silicon-on-insulator 1×2 Y-junction Optical Switch Based on Waveguide-vanishing Effect①②

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    The silicon-on-insulator(SOI)1×2Y-junction optical waveguide switch has been proposed and fabricated,which is based on the large cross-section single-mode rib waveguide condition,the waveguide-vanishing effect and the free-carrier plasma dispersion effect.In the switch,the SOI technique utilizer silicon and silicon dioxide thermal bonding and back-polishing.The insertion loss and extinction ratio of the device are measured to be less than 4.78dB and 20.8dB respectively at a wavelength of 1.3μm and an injection current of 45mA.Response time is about 160ns.

  11. 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.

  12. Electron transport in physically-defined double quantum dots on a highly doped silicon-on-insulator substrate

    Science.gov (United States)

    Yamaoka, Y.; Oda, S.; Kodera, T.

    2016-09-01

    We study electron transport in physically-defined silicon quantum dots (QDs) on a highly doped silicon-on-insulator (SOI) substrate. We show that the QDs can be obtained as designed without unintentional localized states caused by fluctuating dopant potentials even when a highly doped SOI substrate is used. We observe the single electron tunneling phenomena both in the single QDs (SQDs) and in the double QDs (DQDs). The charging energy in the SQDs is ˜18 meV as estimated from the Coulomb diamond. This enables us to further estimate that the diameter of the SQDs is ˜35 nm, which is consistent with the designed fabrication specifications if the voltage condition is taken into account. A change of the charged state in the DQDs is detected using the SQD as a charge sensor. A periodic honeycomb-like charge stability diagram is obtained, which indicates that we achieved the fabrication of DQDs without unintentional localized states.

  13. 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

  14. 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.

  15. 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 ℃.

  16. 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.

  17. 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.

  18. 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.

  19. 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...

  20. High-stroke silicon-on-insulator MEMS nanopositioner: control design for non-raster scan atomic force microscopy.

    Science.gov (United States)

    Maroufi, Mohammad; Fowler, Anthony G; Bazaei, Ali; Moheimani, S O Reza

    2015-02-01

    A 2-degree of freedom microelectromechanical systems nanopositioner designed for on-chip atomic force microscopy (AFM) is presented. The device is fabricated using a silicon-on-insulator-based process and is designed as a parallel kinematic mechanism. It contains a central scan table and two sets of electrostatic comb actuators along each orthogonal axis, which provides displacement ranges greater than ±10 μm. The first in-plane resonance modes are located at 1274 Hz and 1286 Hz for the X and Y axes, respectively. To measure lateral displacements of the stage, electrothermal position sensors are incorporated in the design. To facilitate high-speed scans, the highly resonant dynamics of the system are controlled using damping loops in conjunction with internal model controllers that enable accurate tracking of fast sinusoidal set-points. To cancel the effect of sensor drift on controlled displacements, washout controllers are used in the damping loops. The feedback controlled nanopositioner is successfully used to perform several AFM scans in contact mode via a Lissajous scan method with a large scan area of 20 μm × 20 μm. The maximum scan rate demonstrated is 1 kHz.

  1. High-stroke silicon-on-insulator MEMS nanopositioner: Control design for non-raster scan atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Maroufi, Mohammad, E-mail: Mohammad.Maroufi@uon.edu.au; Fowler, Anthony G., E-mail: Anthony.Fowler@uon.edu.au; Bazaei, Ali, E-mail: Ali.Bazaei@newcastle.edu.au; 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)

    2015-02-15

    A 2-degree of freedom microelectromechanical systems nanopositioner designed for on-chip atomic force microscopy (AFM) is presented. The device is fabricated using a silicon-on-insulator-based process and is designed as a parallel kinematic mechanism. It contains a central scan table and two sets of electrostatic comb actuators along each orthogonal axis, which provides displacement ranges greater than ±10 μm. The first in-plane resonance modes are located at 1274 Hz and 1286 Hz for the X and Y axes, respectively. To measure lateral displacements of the stage, electrothermal position sensors are incorporated in the design. To facilitate high-speed scans, the highly resonant dynamics of the system are controlled using damping loops in conjunction with internal model controllers that enable accurate tracking of fast sinusoidal set-points. To cancel the effect of sensor drift on controlled displacements, washout controllers are used in the damping loops. The feedback controlled nanopositioner is successfully used to perform several AFM scans in contact mode via a Lissajous scan method with a large scan area of 20 μm × 20 μm. The maximum scan rate demonstrated is 1 kHz.

  2. 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...

  3. 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)

  4. Study on the defect-related emissions in the light self-ion-implanted Si films by a silicon-on-insulator structure

    Institute of Scientific and Technical Information of China (English)

    Wang Chong; Yang Yu; Yang Rui-Dong; Li Liang; Xiong Fei; Bao Ji-Ming

    2011-01-01

    This paper reports that the Si+ self-ion-implantation are conducted on the silicon-on-insulator wafers with the 28Si+ doses of 7× 1012, 1× 1013, 4× 1013, and 3× 1014 cm-2, respectively. After the suitable annealing, these samples are characterized by using the photoluminescence technique at different recorded temperatures. Plentiful emission peaks are observed in these implanted silicon-on-insulator samples, including the unwonted intense P' band which exhibits a great potential in the optoelectronic application. These results indicate that severe transformation of the interstitial clusters can be manipulated by the implanting dose at suitable annealing temperatures. The high critical temperatures for the photoluminescence intensity growth of the two signatures are well discussed based on the thermal ionization model of free exciton.

  5. 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)

  6. 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.

  7. 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.

  8. 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.

  9. Low Power-Consumption and High Response Frequency Thermo-Optic Variable Optical Attenuators Based on Silicon-on-Insulator Materials

    Institute of Scientific and Technical Information of China (English)

    FANG Qing; CHEN Peng; XIN Hong-Li; WANG Chun-Xia; LI Fang; LIU Yu-Liang

    2005-01-01

    @@ A novel silicon-on-insulator thermo-optic variable optical attenuator with isolated grooves based on a multimode interference coupler principle is fabricated by the inductive coupled plasma etching technology. The maximum fibre-to-fibre insertion loss is lower than 2.2 dB, the dynamic attenuation range is from 0 to 30 dB in the wavelength range 1500-1600nm, and the maximum power consumption is only 140mW. The response frequency of the fabricated variable optical attenuator is about 30 kHz. Compared to the variable optical attenuator without isolated grooves, the maximum power consumption decreases more than 220mW, and the response frequency rises are more than 20kHz.

  10. A Numerical Study on the Anisotropic Thermal Conduction by Phonon Mean Free Path Spectrum of Silicon in Silicon-on-Insulator Transistor

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyung Sun; Koh, Young Ha; Jin, Jae Sik [Chosun Univ., Kwangju (Korea, Republic of)

    2016-02-15

    The primary concern of this research is to examine the phonon mean free path (MFP) spectrum contribution to heat conduction. The size effect of materials is determined by phonon MFP, and the size effect appears when the phonon MFP is similar to or less than the characteristic length of materials. Therefore, knowledge of the phonon MFP is essential to increase or decrease the heat conduction of a material for engineering applications, such as micro/nanosystems. In this study, frequency dependence of the phonon transport is considered using the Boltzmann transport equation based on a full phonon dispersion model. Additionally, the phonon MFP spectrums of in-plane and out-of plane heat transport are investigated by varying the film thickness of the silicon layer from 41 nm to 177 nm. This will increase the understanding of anisotropic heat conduction in a SOI (Silicon-on-Insulator) transistor.

  11. 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.

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

    Science.gov (United States)

    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 collector—base 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.

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. 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)

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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...

  4. 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.

  5. 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)

  6. 基于绝缘体上硅的一种改进的Mach-Zehnder声光调制器∗%An improved Mach-Zehnder acousto-optic mo dulator on a silicon-on-insulator platform

    Institute of Scientific and Technical Information of China (English)

    秦晨; 余辉; 叶乔波; 卫欢; 江晓清

    2016-01-01

    The interdigital transducer (IDT) of the traditional Mach-Zehnder (MZ) acousto-optic modulator on a silicon-on-insulator (SOI) platform is located outside its two arms. The crest and trough of the surface acoustic wave (SAW) are used to modulate the two arms of the MZ interferometer so as to achieve a high modulation efficiency. Therefore, the distance between the two arms must be odd multiples of half acoustic wavelength. However, since the substrate is usually not uniform, the wavelength of the SAW changes as it transmits through the surface of the device. As a result, the exact distance between the two arms is difficult to choose. On the other hand, the SAW losses a portion of energy after passing through the first arm of the MZ interferometer, so the modulation of the second arm becomes much weaker. To solve these problems, we propose a new structure where its IDT is situated in the middle of the two arms of the MZ interferometer. With this scheme, the two arms of the MZ interferometer are located exactly at the crest and the trough of the SAW, while they are modulated with equal strength. In this paper, we first use the finite element method to simulate the acoustic frequency and the surface displacement of the excited SAW. Then we deduce the refractive index variations of all layers according to their acousto-optic effects. After that, we analyze the influences of different factors on the acousto-optic modulation efficiency, including the type and size of waveguide, the thickness of zinc oxide (ZnO) layer, and the area it covers, the number of electrodes, etc. These parameters are accordingly optimized to enhance the modulation efficiency. Modeling result based on COMSOL Multiphysics indicates that when the width of the strip waveguide is 6 µm, the ZnO layer covers only the area under the IDT and has a thickness of 2.2 µm, and the number of the electrodes is 50, the effective refractive index variation of the waveguide reaches 4.08 × 10−4 provided that

  7. 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.)

  8. 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.

  9. 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.

  10. Analysis of Impact of Thermo Optical Effect on a 2×2 Electro-optical Switch in Silicon-on-insulators%SOI电光开关中热光效应分析

    Institute of Scientific and Technical Information of China (English)

    严清峰; 余金中

    2003-01-01

    分析了SOI (silicon-on-insulator)2×2电光开关工作时热光效应对等离子色散效应的影响.采用二维半导体器件模拟器PISCES-Ⅱ对器件进行了模块.结果表明,热光效应对等离子色散效应的影响与调制区长度密切相关,当调制区长度较短时,热光效应的影响不容忽视;当调制区长度大于500 μm时,这种影响可以忽略不计.

  11. 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

  12. Involvement of nitric oxide in anticompulsive-like effect of agmatine on marble-burying behaviour in mice.

    Science.gov (United States)

    Gawali, Nitin B; Chowdhury, Amrita A; Kothavade, Pankaj S; Bulani, Vipin D; Nagmoti, Dnyaneshwar M; Juvekar, Archana R

    2016-01-01

    In view of the reports that nitric oxide modulates the neurotransmitters implicated in obsessive-compulsive disorder (OCD), patients with OCD exhibit higher plasma nitrate levels, and drugs useful in OCD influence nitric oxide. Agmatine is a polyamine and widely distributed in mammalian brain which interacts with nitrergic systems. Hence, the present study was carried out to understand the involvement of nitrergic systems in the anticompulsive-like effect of agmatine. We used marble-burying behaviour (MBB) of mice as the animal model of OCD, and nitric oxide levels in hippocampus (HC) and cortex homogenate were measured. Results revealed that, agmatine (20 and 40mg/kg, i.p) significantly inhibited the MBB. Intraperitoneal administration of nitric oxide enhancers viz. nitric oxide precursor - l-arginine (l-ARG) (400mg/kg and 800mg/kg) increased MBB as well as brain nitrites levels, whereas treatment with N(G)-nitro-l-arginine methyl ester (l-NAME) neuronal nitric oxide synthase inhibitor (30mg/kg and 50mg/kg, i.p.) and 7-nitroindazole (7-NI) (20mg/kg and 40mg/kg) attenuated MBB and nitrites levels in brain. Further, in combination studies, the anticompulsive-like effect of agmatine (20mg/kg, ip) was exacerbated by prior administration of l-ARG (400mg/kg) and conversely l-NAME (15mg/kg) or 7-NI (10.0mg/kg) attenuated OCD-like behaviour with HC and cortex changes in the levels of NO. None of the above treatment had any significant influence on locomotor activity. In conclusion, Agmatine is effective in ameliorating the compulsive-like behaviour in mice which appears to be related to nitric oxide in brain.

  13. Low-power embedded read-only memory using atom switch and silicon-on-thin-buried-oxide transistor

    Science.gov (United States)

    Sakamoto, Toshitsugu; Tada, Munehiro; Tsuji, Yukihide; Makiyama, Hideki; Hasegawa, Takumi; Yamamoto, Yoshiki; Okanishi, Shinobu; Banno, Naoki; Miyamura, Makoto; Okamoto, Koichiro; Iguchi, Noriyuki; Ogasahara, Yasuhiro; Oda, Hidekazu; Kamohara, Shiro; Yamagata, Yasushi; Sugii, Nobuyuki; Hada, Hiromitsu

    2015-04-01

    We developed an atom-switch read-only memory (ROM) fabricated on silicon-on-thin-buried-oxide (SOTB) for use in a low-power microcontroller for the first time. An atom switch with a low programming voltage and large ON/OFF conductance ratio is suitable for low-power nonvolatile memory. The atom-switch ROM using an SOTB transistor uses a 0.34-1.2 V operating voltage and 12 µA/MHz active current (or 4.5 µW/MHz active power). Furthermore, the sleep current is as low as 0.4 µA when a body bias voltage is applied to the SOTB.

  14. Ratiometric, filter-free optical sensor based on a complementary metal oxide semiconductor buried double junction photodiode.

    Science.gov (United States)

    Yung, Ka Yi; Zhan, Zhiyong; Titus, Albert H; Baker, Gary A; Bright, Frank V

    2015-07-16

    We report a complementary metal oxide semiconductor integrated circuit (CMOS IC) with a buried double junction (BDJ) photodiode that (i) provides a real-time output signal that is related to the intensity ratio at two emission wavelengths and (ii) simultaneously eliminates the need for an optical filter to block Rayleigh scatter. We demonstrate the BDJ platform performance for gaseous NH3 and aqueous pH detection. We also compare the BDJ performance to parallel results obtained by using a slew scanned fluorimeter (SSF). The BDJ results are functionally equivalent to the SSF results without the need for any wavelength filtering or monochromators and the BDJ platform is not prone to errors associated with source intensity fluctuations or sensor signal drift.

  15. 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.

  16. 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.

  17. 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.

  18. 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...

  19. 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).

  20. 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.

  1. 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 5(2)S(1/2) → 5(2)P(3/2) 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. PMID:27036764

  2. Chemical interaction at the buried silicon/zinc oxide thin-film solar cell interface as revealed by hard X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wimmer, M., E-mail: mark.wimmer@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Gerlach, D.; Wilks, R.G.; Scherf, S.; Félix, R. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Lupulescu, C. [Institute for Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Ruske, F.; Schondelmaier, G.; Lips, K. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Hüpkes, J. [Institute for Energy Research, Forschungszentrum Jülich GmbH, Leo-Brandt-Straße, 52425 Jülich (Germany); Gorgoi, M. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Eberhardt, W. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Institute for Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin (Germany); Rech, B. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Bär, M., E-mail: marcus.baer@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus, Konrad-Wachsmann-Allee 1, 03046 Cottbus (Germany)

    2013-10-15

    Highlights: •We used HAXPES to identify chemical interactions at the buried silicon/aluminum-doped zinc oxide thin-film solar cell interface. •The results indicate a diffusion of zinc and aluminum into the silicon upon annealing procedures which are part of the solar cell processing. •The contamination of the silicon may be detrimental for the solar cell performance. -- Abstract: Hard X-ray photoelectron spectroscopy (HAXPES) is used to identify chemical interactions (such as elemental redistribution) at the buried silicon/aluminum-doped zinc oxide thin-film solar cell interface. Expanding our study of the interfacial oxidation of silicon upon its solid-phase crystallization (SPC), in which we found zinc oxide to be the source of oxygen, in this investigation we address chemical interaction processes involving zinc and aluminum. In particular, we observe an increase of zinc- and aluminum-related HAXPES signals after SPC of the deposited amorphous silicon thin films. Quantitative analysis suggests an elemental redistribution in the proximity of the silicon/aluminum-doped zinc oxide interface – more pronounced for aluminum than for zinc – as explanation. Based on these insights the complex chemical interface structure is discussed.

  3. 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

  4. 一种改进的2×2 SOI Mach-Zehnder热光开关%An Improvement on 2×2 Silicon-on-Insulator Mach-Zehnder Thermo-Optical

    Institute of Scientific and Technical Information of China (English)

    杨笛; 余金中; 陈少武

    2008-01-01

    本文设计并制作了基于强限制多模干涉耦合器的2×2 SOI马赫-曾德热光开关.这种光开关采用了深刻蚀结构的多模干涉耦合器和输入/输出波导,较大地提高了干涉耦合器的性能并减少了连接耦合损耗.同时,在调制臂区域采用浅刻蚀结构,保持其单模调制状态.深刻蚀多模干涉耦合器具有优越的特性,在实验中测得不均衡度只有0.03 dB,插入损耗-0.6 dB.基于这种耦合器的新型热光开关,其插入损耗为-6.8 dB,其中包括光纤-波导耦合损耗-4.3 dB,开关时间为6.8 μs.%An improved 2×2 silicon-on-insulator Mach-Zehnder thermo-optical switch is designed and fabricated, which is based on strongly guided multimode interference couplers and single-mode phase-shifting arms. The multimode interference couplers and input/output waveguides are deeply etched to improve coupler performances and coupler-waveguide coupling efficiencies. However, shallow etching is used in the phase-shifting arms to guarantee single-mode property. The strongly guided coupler presents an attractive uniformity about 0.03 dB and a low propagation loss of -0.6 dB. The 2×2 switch shows an insertion loss as low as -6.8 dB, where the fiber-waveguide coupling loss of -4.3 dB is included, and the response-time is measured as short as 6.8 μs, which are much better than our previous results.

  5. Investigation of AlN Thin Films as Buried Insulator in SOI Structure

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Self-heating effects in silicon-on-insulator (SOI) devices limit the applicability of SOI materials in electronics in cases where high power dissipation is expected. AlN film as a potential candidate for buried insulator material in SOI-structures is investigated. Ion-beam-enhanced deposition (IBED) is used to manufacture large area AlN films. SIMS measurements indicate the formation of AlN films. The characterization of the films reveals that the quality of the films strongly depends on the evaporation rate of Al. For the film with high quality deposited at 0.05nm/s, it has higher component of N, excellent dielectric property and a smoother surface with roughness RMS value of 0.13nm, and can be bonded directly at room temperature by the smart-cut process. SOI structure with the AlN film as buried insulator has formed successfully for the first time, which is confirmed by XTEM micrograph.

  6. 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...

  7. 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.)

  8. 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

  9. Integrated MMI Optical Couplers and Optical Switches in Silicon-on-Insulator Technology%采用绝缘体上的半导体技术制备集成的多模干涉型光耦合器和光开关

    Institute of Scientific and Technical Information of China (English)

    余金中; 魏红振; 严清峰; 夏金松; 张小峰

    2003-01-01

    在光学系统中,SOI(绝缘体上的半导体)上制备集成的MMI(多模干涉)型光耦合器已成为一种愈来愈引人注目的无源器件.由于Si和SiO2之间具有大的折射率差,在SOI波导中可以采用SiO2薄膜(<1.0μm)作限制层,这与超大规模集成电路工艺相兼容.描述了采用SOI技术制备集成的MMI型光耦合器和光开关的设计和制造结果.业已证实,2×2 MMI-MZI(多模干涉-麦赫-曾德干涉)型热光开关的开关时间小于20μs.%Integrated multimode interference (MMI) coupler based on silicon-on-insulator(SOI) has been becoming a kind of more and more attractive device in optical systems. SiO2thin cladding layers (<1.0 μm) can be usedin SOI waveguide due to the large index step be-tween Si and SiO2, making them compatible with VLSI technology. The design and fabrica-tion of MMI optical couplers and optical switches in SOI technology are presented in thepa-per. We demonstrated the switching time of 2 × 2 MMI-MZI thermo-optical switch is less than 20 μs:

  10. 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 potential method for supporting the constantly increasing internet traffic demand [1]. Mode converters are important components necessary to support on-chip processing of MDM signals and multiple approaches has been followed in realizing such devices [2], [3]. Topology optimization (TO) [4] is a powerful...... inverse design tool which has experimentally proven to deliver robust designs with controllable bandwidth and low loss [5], [6]. Here it is shown how TO has been used to obtain a small footprint, low-loss, broad-band design for mode conversion between the transverse electric fundamental even (TE0) mode...

  11. 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.

  12. 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.

  13. 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 ...

  14. 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

  15. 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)

  16. 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.

  17. 47 CFR 32.2423 - Buried cable.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Buried cable. 32.2423 Section 32.2423... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2423 Buried cable. (a) This account shall include the original cost of buried cable as well as the cost of other material...

  18. 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

  19. 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.

  20. 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 ...

  1. 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

  2. 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.)

  3. 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.

  4. 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.

  5. Explicit Compact Surface-Potential and Drain-Current Models for Generic Asymmetric Double-Gate Metal-Oxide-Semiconductor Field-Effect Transistors

    Science.gov (United States)

    Zhu, Zhaomin; Zhou, Xing; Chandrasekaran, Karthik; Rustagi, Subhash C.; See, Guan Huei

    2007-04-01

    In this paper, explicit surface potentials for undoped asymmetric-double-gate (a-DG) metal-oxide-semiconductor field-effect transistors (MOSFETs) suitable for compact model development are presented for the first time. The model is physically derived from Poisson’s equation in each region of operation and adopted in a unified regional approach. The proposed model is physically scalable with oxide/channel thicknesses and has been verified with generic implicit solutions for independent gate biases as well as for different gate/oxide materials. The model is extendable to silicon-on-insulator (SOI) and symmetric-DG (s-DG) MOSFETs. Finally, a continuous, explicit drain-current equation has been derived on the basis of the developed explicit surface-potential solutions.

  6. 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).

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. A Buried Precambrian Impact Crater in Scotland

    Science.gov (United States)

    Simms, M. J.

    2016-08-01

    Field evidence indicates that the source of the Stac Fada impact deposit (Mesoproterozoic) in NW Scotland was to the east, and that the now buried crater is represented by the 40+ km diameter Lairg Gravity Low.

  12. 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...

  13. Design of a 1200-V Thin-Silicon-Layer p-Channel SOI LDMOS Device

    Institute of Scientific and Technical Information of China (English)

    胡盛东; 张玲; 罗小蓉; 张波; 李肇基; 吴丽娟

    2011-01-01

    A 1200-V thin-silicon-layer p-channel silicon-on-insulator(SOI)lateral double-diffused metal-oxide-semiconductor (LDMOS)transistor is designed.The device named INI SO1 p-LDMOS is characterized by a series of equidistant high concentration n+ islands inserted at the interface of a top silicon layer and a buried oxide layer.Accumulation-mode holes,caused by the electric potential dispersion between the device surface and the substrate,are located in the spacing between two neighboring n+ islands,and greatly enhance the electric field of the buried oxide layer and therefore,effectively increase the device breakdown voltage.Based on a 2-μm-thick buried oxide layer and a 1.5-μm-thick top silicon layer,a breakdown voltage of 1224 V is obtained,resulting in the high electric field(608 V/μm)of the buried oxide layer.%A 1200-V thin-silicon-layer p-channel silicon-on-insulator (SOI) lateral double-diffused metal-oxide-semiconductor (LDMOS) transistor is designed. The device named INI SOI p-LDMOS is characterized by a series of equidistant high concentration n+ islands inserted at the interface of a top silicon layer and a buried oxide layer. Accumulation-mode holes, caused by the electric potential dispersion between the device surface and the substrate, are located in the spacing between two neighboring n+ islands, and greatly enhance the electric field of the buried oxide layer and therefore, effectively increase the device breakdown voltage. Based on a 2-[im-thick buried oxide layer and a 1.5-um-thick top silicon layer, a breakdown voltage of 1224 V is obtained, resulting in the high electric field (608 V/\\im) of the buried oxide layer.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. A vertically integrated dynamic RAM-cell: Buried bit line memory cell with floating transfer layer

    NARCIS (Netherlands)

    Mouthaan, Ton; Vertregt, Maarten

    1986-01-01

    A charge injection device has been realized in which charge can be injected on to an MOS-capacitor from a buried layer via an isolated transfer layer. The cell is positioned vertically between word and bit line. LOCOS (local oxidation) is used to isolate the cells and (deep) ion implantation to real

  19. FDTD Computation of Scattering by Buried Objects

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-yan; SHENG Xin-qing

    2007-01-01

    A computational approach of scattering by buried objects is presented by using finite-difference time-domain (FDTD) method, the uniaxial perfectly matched layer (UPML), and reciprocity theorem. The numerical performance of this approach is investigated by numerical experiments. The radar cross sections (RCS) of various buried objects with different electrical sizes, shapes, dielectric constants, are computed and analyzed. The results show that for the conducting cube, the RCS curves are fluctuant, but for the sphere shape one, the curves are smooth. Comparing with scattering in the free space, the ground greatly affects the RCS by dielectric targets, but little does by conducting targets. For the buried dielectric objects, iterative steps can be evaluated by four to five round-trip traversals of the Huygens box, but for the conducting ones, the time steps can be reduced to three round-trip traversals. When the ground is lossy, the run-time can be reduced more to two round-trip traversals.

  20. 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.

  1. Topology optimized mode multiplexing in silicon-on-insulator photonic wire waveguides

    DEFF Research Database (Denmark)

    Frellsen, Louise Floor; Ding, Yunhong; Sigmund, Ole;

    2016-01-01

    We design and experimentally verify a topology optimized low-loss and broadband two-mode (de-)multiplexer, which is (de-)multiplexing the fundamental and the first-order transverse-electric modes in a silicon photonic wire. The device has a footprint of 2.6 μm x 4.22 μm and exhibits a loss 14 d......B in the C-band. Furthermore, we demonstrate that the design method can be expanded to include more modes, in this case including also the second order transverse-electric mode, while maintaining functionality....

  2. Optical and thermal properties of periodic photonic structures on a silicon-on-insulator platform

    Science.gov (United States)

    Song, Weiwei

    Silicon photonics is the leading candidate to fulfill the high bandwidth requirement for the future communication networks. Periodic photonic structures, due to their fascinating properties including compact size, high efficiency, and ease of design, play an important role in photonic systems. In this dissertation, SOI-based one-dimensional and two-dimensional periodic photonic structures are studied. Low crosstalk, high density integration of bus waveguides is demonstrated by employing a novel waveguide array structure. Inspired by the low coupling strength shown by initial pair waveguide experiments, novel waveguide array structures are studied by generalizing the nearest-neighbor tight-bonding model. Based on the theory, waveguide arrays have been designed and fabricated. The waveguide arrays have been characterized to demonstrate high density bus waveguides with minimal crosstalk. Two-dimensional photonic crystal waveguide (PCW) structure was then investigated aiming at reducing the propagation loss. A general cross-sectional eigenmode orthogonality relation is first derived for a one dimensional periodic system. Assisted by this orthogonality, analytic formulas are obtained to describe the propagation loss in PCW structures. By introducing the radiation and backscattering loss factors alpha1 and alpha2, the total loss coefficient alpha can be written as alpha = alpha1ng + alpha2ng2 ( ng is the group index). It is analytically shown the backscattering loss generally dominates the radiation loss for ng>10. Combined with systematic simulations of loss dependences on key structure parameters, this analytic study helps identify promising strategies to reduce the slow light loss. The influence of the substrate on the performance of a thermo-optic tuning photonic crystal device was studied in the following section. The substrate-induced thermo-optic tuning is obtained as a function of key physical parameters, based on a semi-analytic theory that agrees well with numeric simulations. It is shown that for some devices, the substrate's contribution to the thermo-optic tuning can exceed 10% for a heater located in the waveguide core and much higher for some other configurations. The slow response of the substrate may also significantly slow down the overall response time of the device. Strategies of minimizing the substrate's influence are discussed.

  3. Structure Tuning of Line-Defect Waveguides Based on Silicon-on-Insulator Photonic Crystal Slabs

    Institute of Scientific and Technical Information of China (English)

    WANG Chun-Xia; XU Xing-Sheng; XIONG Gui-Guang; HU Hai-Yang; SONG Qian; DU Wei; CHEN Hong-Da

    2007-01-01

    We present fabrication and experimental measurement of a series of photonic crystal waveguides. The complete devices consist of an injector taper down from 3 μm into a triangular-lattice air-hole single-line-defect waveguide with lattice constant from 410nm to 470nm and normalized radius 0.31. We fabricate these devices on a siliconon-insulator substrate and characterize them using a tunable laser source over a wavelength range from 1510 nm to 1640nm. A sharp attenuation at photonic crystal waveguide mode edge is observed for most structures. The edge of guided band is shifted about 30nm with the 10nm increase of the lattice constant. We obtain high-efficiency light propagation and broad flat spectrum response of the photonic crystal waveguides.

  4. 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

  5. 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 (

  6. 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

  7. Polarization diversity DPSK demodulator on the silicon-on-insulator platform with simple fabrication

    DEFF Research Database (Denmark)

    Ding, Yunhong; Huang, Bo; Ou, Haiyan;

    2013-01-01

    We demonstrate a novel polarization diversity differential phase-shift keying (DPSK) demodulator on the SOI platform, which is fabricated in a single lithography and etching step. The polarization diversity DPSK demodulator is based on a novel polarization splitter and rotator, which consists of ...... penalty of only 3 dB when the input state of polarization is scrambled are obtained for 40 Gbit/s non return-to-zero DPSK (NRZ-DPSK) demodulation....

  8. 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....

  9. 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

  10. 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

  11. Detection of buried mines with seismic sonar

    Science.gov (United States)

    Muir, Thomas G.; Baker, Steven R.; Gaghan, Frederick E.; Fitzpatrick, Sean M.; Hall, Patrick W.; Sheetz, Kraig E.; Guy, Jeremie

    2003-10-01

    Prior research on seismo-acoustic sonar for detection of buried targets [J. Acoust. Soc. Am. 103, 2333-2343 (1998)] has continued with examination of the target strengths of buried test targets as well as targets of interest, and has also examined detection and confirmatory classification of these, all using arrays of seismic sources and receivers as well as signal processing techniques to enhance target recognition. The target strengths of two test targets (one a steel gas bottle, the other an aluminum powder keg), buried in a sand beach, were examined as a function of internal mass load, to evaluate theory developed for seismic sonar target strength [J. Acoust. Soc. Am. 103, 2344-2353 (1998)]. The detection of buried naval and military targets of interest was achieved with an array of 7 shaker sources and 5, three-axis seismometers, at a range of 5 m. Vector polarization filtering was the main signal processing technique for detection. It capitalizes on the fact that the vertical and horizontal components in Rayleigh wave echoes are 90 deg out of phase, enabling complex variable processing to obtain the imaginary component of the signal power versus time, which is unique to Rayleigh waves. Gabor matrix processing of this signal component was the main technique used to determine whether the target was man-made or just a natural target in the environment. [Work sponsored by ONR.

  12. 7 CFR 1755.505 - Buried services.

    Science.gov (United States)

    2010-01-01

    ... avoid damage from lawn mowers, animals, gardening operations, etc. (3) Buried service wire or cable... 5 U.S.C. 552(a) and 1 CFR part 51. Copies are available from NFPA, 1 Batterymarch Park, P.O. Box... company's wires or cables Electric supply wire including neutral and grounding conductors: Open 4...

  13. 47 CFR 32.6423 - Buried cable expense.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Buried cable expense. 32.6423 Section 32.6423... FOR TELECOMMUNICATIONS COMPANIES Instructions for Expense Accounts § 32.6423 Buried cable expense. (a) This account shall include expenses associated with buried cable. (b) Subsidiary record...

  14. 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.

    2016-01-01

    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.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. Analog performance of standard and uniaxial strained triple-gate SOI FinFETs under x-ray radiation

    Science.gov (United States)

    Bordallo, C. C. M.; Teixeira, F. F.; Silveira, M. A. G.; Martino, J. A.; Agopian, P. G. D.; Simoen, E.; Claeys, C.

    2014-12-01

    The influence of x-ray irradiation on the main digital and analog parameters of triple gate silicon-on-insulator FinFETs is investigated for unstrained and uniaxially strained devices. Comparing the p- and n-MuGFET response to radiation, x-rays can be more harmful for nMuGFETs than for the p-type counterparts due to the back-interface leakage current, which is generated by the positive charges trapped in the buried oxide. However, in pMuGFETs, the radiation tends to suppress the parasitic back-conduction, resulting in an improvement of the device performance.

  20. Buried caldera of mauna kea volcano, hawaii.

    Science.gov (United States)

    Porter, S C

    1972-03-31

    An elliptical caldera (2.1 by 2.8 kilometers) at the summit of Mauna Kea volcano is inferred to lie buried beneath hawaiite lava flows and pyroclastic cones at an altitude of approximately 3850 meters. Stratigraphic relationships indicate that hawaiite eruptions began before a pre-Wisconsin period of ice-cap glaciation and that the crest of the mountain attained its present altitude and gross form during a glaciation of probable Early Wisconsin age.

  1. 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).

  2. 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.

  3. CMOS-compatible method for doping of buried vertical polysilicon structures by solid phase diffusion

    Science.gov (United States)

    Turkulets, Yury; Silber, Amir; Ripp, Alexander; Sokolovsky, Mark; Shalish, Ilan

    2016-03-01

    Polysilicon receives attention nowadays as a means to incorporate 3D-structured photonic devices into silicon processes. However, doping of buried layers of a typical 3D structure has been a challenge. We present a method for doping of buried polysilicon layers by solid phase diffusion. Using an underlying silicon oxide layer as a dopant source facilitates diffusion of dopants into the bottom side of the polysilicon layer. The polysilicon is grown on top of the oxide layer, after the latter has been doped by ion implantation. Post-growth heat treatment drives in the dopant from the oxide into the polysilicon. To model the process, we studied the diffusion of the two most common silicon dopants, boron (B) and phosphorus (P), using secondary ion mass spectroscopy profiles. Our results show that shallow concentration profiles can be achieved in a buried polysilicon layer using the proposed technique. We present a quantitative 3D model for the diffusion of B and P in polysilicon, which turns the proposed method into an engineerable technique.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. 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)

  10. 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).

  11. 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).

  12. 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

  13. 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)

  14. A Buried Vertical Filter for Micro and Nanoparticle Filtration

    NARCIS (Netherlands)

    Li, S.J.; Shen, C.; Sarro, P.M.

    2011-01-01

    This paper presents a silicon micromachined filter for micro- and nanoparticles. The filter is vertical and completely buried beneath the surface. The buried aspect allows additional features to be integrated above the filter, while the vertical aspect allows the creation of highly uniform pores and

  15. 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

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

    DEFF Research Database (Denmark)

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

    2004-01-01

    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...

  17. 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

  18. 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).

  19. 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

  20. 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.

  1. Buried waste containment system materials. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Weidner, J.R.; Shaw, P.G.

    1997-10-01

    This report describes the results of a test program to validate the application of a latex-modified cement formulation for use with the Buried Waste Containment System (BWCS) process during a proof of principle (POP) demonstration. The test program included three objectives. One objective was to validate the barrier material mix formulation to be used with the BWCS equipment. A basic mix formula for initial trials was supplied by the cement and latex vendors. The suitability of the material for BWCS application was verified by laboratory testing at the Idaho National Engineering and Environmental Laboratory (INEEL). A second objective was to determine if the POP BWCS material emplacement process adversely affected the barrier material properties. This objective was met by measuring and comparing properties of material prepared in the INEEL Materials Testing Laboratory (MTL) with identical properties of material produced by the BWCS field tests. These measurements included hydraulic conductivity to determine if the material met the US Environmental Protection Agency (EPA) requirements for barriers used for hazardous waste sites, petrographic analysis to allow an assessment of barrier material separation and segregation during emplacement, and a set of mechanical property tests typical of concrete characterization. The third objective was to measure the hydraulic properties of barrier material containing a stop-start joint to determine if such a feature would meet the EPA requirements for hazardous waste site barriers.

  2. 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.

  3. 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.

  4. 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.

  5. 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)

  6. Sub-micron imaging of buried integrated circuit structures using scanning confocal electron microscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, S. P.; Levine, Z.; Zaluzec, N. J.; Materials Science Division; Northern Arizona Univ.; NIST

    2002-09-09

    Two-dimensional images of model integrated circuit components were collected using the technique of scanning confocal electron microscopy. For structures embedded about 5 {mu}m below the surface of a silicon oxide dielectric, a lateral resolution of 76{+-}9 nm was measured. Elemental mapping via x-ray emission spectrometry is demonstrated. A parallax analysis of images taken for various tilt angles to the electron beam allowed determination of the spacing between two wiring planes. The results show that scanning confocal electron microscopy is capable of probing buried structures at resolutions that will be necessary for the inspection of next-generation integrated circuit technology.

  7. Mallet finger deformities treated by buried purse-string suture

    Institute of Scientific and Technical Information of China (English)

    YAO Jian-min; ZHAO Feng-jing

    2011-01-01

    Objective: To investigate the efficacy of buried purse-string suture in the treatment of mallet finger deformities. Methods: From February 2009 to February 2010, 12 patients with closed non-fracture mallet fingers were treated by buried purse-string suture. The rupture tendons were sutured by purse-string suture with an atraumatic needle, and the knots were buried under subcutaneous tissue. External fixator was used at the extension position of the finger every night within three weeks after operation. Results: All patients were followed up for 6-12 months, mean 7 months. According to the Patel's evaluation criteria, 2 cases (17%) obtained excellent results, 7 good (58%), 2 fair (17%) and 1 poor (8%). The overall rate of the cases with excellent and good outcomes was 75%. Conclusion: Buried purse-string suture is an easy and effective way to treat mallet finger deformities, with no serious postoperative complications or no need for reoperation.

  8. A Review of Celestial Burying Ground in Tibet

    Institute of Scientific and Technical Information of China (English)

    YUQIAN

    2005-01-01

    Celestial burying ground ,also called “Mandala”,is where life leaves and comes.A huge piece of stone hidden in high mountains is surrounded by burning plants that give up smoke going up into the air.

  9. 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

  10. 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.

  11. INCREASING BREAKDOWN VOLTAGE OF LDMOST USING BURIED LAYER

    Institute of Scientific and Technical Information of China (English)

    Han Lei; Ye Xingning; Chen Xingbi

    2003-01-01

    A new LDMOST structure, named B-LDMOST that has a buried layer under the drain is proposed. The buried layer is not connected to the drift region, so it can optimize the vertical field distribution and increase breakdown voltage. The analysis and the simulated results show that B-LDMOST can increase breakdown voltage, with almost negligible influence on the other parameters such as on-resistance, switching time, and so on.

  12. INCREASING BREAKDOWN VOLTAGE OF LDMOST USING BURIED LAYER

    Institute of Scientific and Technical Information of China (English)

    HanLei; YeXingning; 等

    2003-01-01

    A new LDMOST structure,named B-LDMOST that has a buried layer under the drain is proposed.The buried layer is not connected to the drift region,so it can optimize the vertical field distribution and increase breakdown voltage.The analysis and the simulated results show that B-LDMOST can increase breakdown voltage,with almost negligible influence on the other parameters such as on-resistance,switching time,and so om.

  13. 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...

  14. 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...

  15. Buried and Encapsulated Ducts, Jacksonville, Florida (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    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. There are three possible combinations of BED strategies: (1) buried ducts; (2) encapsulated ducts (with ccSPF); and (3) buried and encapsulated ducts. The best solution for each situation depends on the climate, age of the house, and the configuration of the HVAC system and attic. For new construction projects, the team recommends that ducts be both encapsulated and buried as the minimal planning and costs required for this will yield optimal energy savings. The encapsulated/buried duct strategy, which utilizes ccSPF to address condensation concerns, is an approach that was developed specifically for humid climates.

  16. 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

  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. 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...

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

    Science.gov (United States)

    Fowler, Anthony G; Maroufi, Mohammad; Moheimani, S O Reza

    2015-04-01

    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.

  20. 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.

  1. 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...

  2. 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.

  3. Silicon-on-Insulator-Based Broadband 1×3 Adiabatic Splitter with Simultaneous Tapering of Velocity and Coupling

    Science.gov (United States)

    Gong, Yuan-Hao; Li, Zhi-Yong; Yu, Jin-Zhong; Yu, Yu-De

    2016-09-01

    Not Available Supported by the National High-Technology Research and Development Program of China under Grant Nos 2015AA016904 and 2013AA014402, the National Basic Research Program of China under Grant No 2011CB301701, and the National Natural Science Foundation of China under Grant No 61275065.

  4. 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.

  5. Low-energy MOS depletion modulators in silicon-on-insulator micro-donut resonators coupled to bus waveguides.

    Science.gov (United States)

    Soref, Richard; Guo, Junpeng; Sun, Greg

    2011-09-12

    Electrical, optical and electro-optical simulations are presented for a waveguided, resonant, bus-coupled, p-doped Si micro-donut MOS depletion modulator operating at the 1.55 μm wavelength. To minimize the switching voltage and energy, a high-K dielectric film of HfO₂ or ZrO₂ is chosen as the gate dielectric, while a narrow ring-shaped layer of p-doped poly-silicon is selected for the gate electrode, rather than metal, to minimize plasmonic loss loading of the fundamental TE mode. In a 6-μm-diam high-Q resonator, an infrared intensity extinction ratio of 6 dB is predicted for a modulation voltage of 2 V and a switching energy of 4 fJ/bit. A speed-of-response around 1 ps is anticipated. For a modulator scaled to operate at 1.3 μm, the estimated switching energy is 2.5 fJ/bit.

  6. Effect of Hydrogen Implantation on SIMOX SOI Materials

    Institute of Scientific and Technical Information of China (English)

    易万兵; 陈静; 陈猛; 王曦; 邹世昌

    2004-01-01

    Hydrogen ions were implanted into separation by implantation of oxygen (SIMOX) silicon-on-insulator (SOI)wafers near the oxygen-implantation-induced damage peak under different conditions of energy and dose. It was found that the implanted hydrogen ions not only accelerate the diffusion of oxygen atoms from the annealing ambience into the wafer but also cause an outward diffusion of oxygen atoms in the buried oxide (BOX) layer.Thus, greatly broadened buried oxygen-rich (BOR) layers were formed in our experiments, which are 18%-79%broader than the BOX layer of standard SIMOX SOI wafers under the same conditions of oxygen implantation.The mechanism was discussed. A potential low cost method to fabricate SIMOX SOI wafers is proposed.

  7. The evolution of the River Nile. The buried saline rift lakes in Sudan—I. Bahr El Arab Rift, the Sudd buried saline lake

    Science.gov (United States)

    Salama, Ramsis B.

    The River Nile in Sudan, was during the Tertiary, a series of closed lake basins. Each basin occupying one of the major Sudanese rift systems (Salama, 1985a). In this paper evidence is presented for the presence of the buried saline Sudd Lake in Bahr El Arab rift. The thick Tertiary sediments filling the deep grabens were eroded from the elevated blocks; Jebel Marra, Darfur Dome, Nuba Mountains and the Nile-Congo Divide. The thick carbonate deposits existing at the faulted boundaries of Bahr El Arab defines the possible boundaries between the fresh and saline water bodies. The widespread presence of kanker nodules in the sediments was a result of continuous efflorescence, leaching and evaporative processes. The highly saline zone in the central part of the Sudd was formed through the same processes with additional sulphate being added by the oxidation of the hydrogen sulphide gases emanating from the oil fields.

  8. 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.

  9. Damage Assessment for Buried Structures Against Internal Blast Load

    Institute of Scientific and Technical Information of China (English)

    MA Guowei; HUANG Xin; LI Jianchun

    2008-01-01

    The soil-structure interaction(SSI)decoupling is applied to simplify buried structure against internal blast lpad as spring effect.Shear failure.bending failure and Combined failure modes are considered based on five transverse velocity profiles for the rigid-plastic structural element.The critical equations for shear and bending failure are derived respectively.Pressure impulse diagrams are accordingly developed to assess damage of the buried structures against internal blast lpad.Cornparison is done to show influences of soil-structure interaction and shear to-bending strength ratio of a structural element.A case study is conducted to show the application of damage assessment to a reinforced concrete beam element of buried structure.

  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. 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.

  12. Heating and cooling potential of buried pipes in southern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Abadie, Marc O.; Santos, Gerson H. dos; Freire, Roberto Z.; Mendes, Nathan [Pontificia Universidade Catolica do Parana (PUC-PR), Curitiba, PR (Brazil). Lab. de Sistemas Termicos], e-mail: mabadie@univ-lr.fr, e-mail: gerson.santos@pucpr.br, e-mail: rozafre@terra.com.br; Mendes, Nathan [Pontifical Catholic University of Parana (PUCPR/CCET), Curitiba, PR (Brazil). Thermal Systems Laboratory - LST], e-mail: nathan.mendes@pucpr.br

    2006-07-01

    The present numerical study aims to evaluate the heating and cooling potential of buried pipes in three cities of South Brazil i.e. Curitiba, Florianopolis and Porto-Alegre. In a first part, ground temperatures at the buried pipe location (between 1 and 3 m depth) are calculated by both a simplified model and a three-dimensional volume-finite code (SOLUM). Then, a prototypical house and its buried pipe are modeled with a building energy simulation tool (TRNSYS) to evaluate the positive and negative effects of such system on thermal comfort and heating and cooling energy. Results show that this passive system is particularly efficient in Curitiba, can reduce energy consumption in Porto Alegre and is not well-adapted to Florianopolis. (author)

  13. Comprehensive Multi-Level Exploration of Buried Active Faults: an Example of the Yinchuan Buried Active Fault

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The paper introduces the steps and methods of multi-approach, multi-level exploration of buried faults in thick Quaternary sediment regions by taking the test exploration of the Yinchuan active fault as example. Based on the comprehensive analyses of previous data, we choose the Xinqushao Village of Xingqing District of Yinchuan City as the test site for the comprehensive exploration. Firstly, we adopted shallow seismic investigation with group intervals of 10m, 5m and 1m to gradually trace layer by layer the master fault of the Yinchuan buried fault from a deep depth to a shallow depth where drilling could be used. Then, with composite geological profile drilling, we determined the precise location and dip angle of the fault. The drilling show the buried depth of the upper offset point is 8.3m. Finally, large-scale trenching revealed that the actual buried depth of the upper offset point of the fault is 1.5m from the ground surface and there are paleoearthquake events of 5 stages. Combined with the prellmiuary result of corresponding sample age, we conclude the Yinchuan buried fault is a mid to late Holocene active fault.

  14. 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.

  15. 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...

  16. 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

  17. Ground Penetrating Radar Imaging of Buried Metallic Objects

    DEFF Research Database (Denmark)

    Polat, A. Burak; Meincke, Peter

    2001-01-01

    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...

  18. 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

  19. 49 CFR 195.248 - Cover over buried pipeline.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Cover over buried pipeline. 195.248 Section 195.248 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION...

  20. 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.

  1. 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

  2. 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

  3. 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

  4. Julia集的淹没分支%BURIED COMPONENTS OF A JULIA SET

    Institute of Scientific and Technical Information of China (English)

    孙业顺; 杨重骏

    2002-01-01

    In this note,it is shown that if a rational function f of degree≥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.

  5. 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.

  6. 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

  7. 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.

  8. Centrifuge modeling of PGD response of buried pipe

    Institute of Scientific and Technical Information of China (English)

    Michael O'Rourke; Vikram Gadicherla; Tarek Abdoun

    2005-01-01

    A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented.The physical characteristics of the RPI's 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics,(diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. 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

  14. Analytical and Experimental Evaluation of a Buried Shelter

    Directory of Open Access Journals (Sweden)

    C. K. Gautam

    2007-03-01

    Full Text Available The design, analysis, and testing of a buried circular cylindrical shelter has been describedin this paper. This shelter may be used for personnel protection in emergency situations likeaccidental blast, terrorist attack, etc. Various criteria have been used for designing and analysingthe shelter. The shelter has been analysed using a software package called ANSYS for findingout the stresses, deflections, buckling load factors, and buckled mode shapes. The shelter wasburied under earthcover (1.5 m and tested for the required loading.

  15. Survival of buried Sclerotinia sclerotiorum sclerotia in undisturbed soil

    OpenAIRE

    Ćosić J.; Jurković D.; Vrandečić K.; Kaučić D.

    2012-01-01

    Sclerotia of S. sclerotiorum are surviving structures and the most important source of inoculum in sunflower fields. There are few studies about sclerotia survival in uncultivated soil and in accordance to that our objective was to establish the effect of burial depth on sclerotia longevity and the ability of carpogenic germination. In the trial (2009-2011) sclerotia were buried at the depth of 5, 10 and 30 cm and recovered every year in June. In laboratory ...

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. Structural coupling between FKBP12 and buried water.

    Science.gov (United States)

    Szep, Szilvia; Park, Sheldon; Boder, Eric T; Van Duyne, Gregory D; Saven, Jeffery G

    2009-02-15

    Globular proteins often contain structurally well-resolved internal water molecules. Previously, we reported results from a molecular dynamics study that suggested that buried water (Wat3) may play a role in modulating the structure of the FK506 binding protein-12 (FKBP12) (Park and Saven, Proteins 2005; 60:450-463). In particular, simulations suggested that disrupting a hydrogen bond to Wat3 by mutating E60 to either A or Q would cause a structural perturbation involving the distant W59 side chain, which rotates to a new conformation in response to the mutation. This effectively remodels the ligand-binding pocket, as the side chain in the new conformation is likely to clash with bound FK506. To test whether the protein structure is in effect modulated by the binding of a buried water in the distance, we determined high-resolution (0.92-1.29 A) structures of wild-type FKBP12 and its two mutants (E60A, E60Q) by X-ray crystallography. The structures of mutant FKBP12 show that the ligand-binding pocket is indeed remodeled as predicted by the substitution at position 60, even though the water molecule does not directly interact with any of the amino acids of the binding pocket. Thus, these structures support the view that buried water molecules constitute an integral, noncovalent component of the protein structure. Additionally, this study provides an example in which predictions from molecular dynamics simulations are experimentally validated with atomic precision, thus showing that the structural features of protein-water interactions can be reliably modeled at a molecular level.

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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.

  9. Properties and mechanisms of Z2-FET at variable temperature

    Science.gov (United States)

    Dirani, Hassan El; Solaro, Yohann; Fonteneau, Pascal; Ferrari, Philippe; Cristoloveanu, Sorin

    2016-01-01

    This paper presents a systematic study of Z2-FET (Zero Subthreshold Swing and Zero Impact Ionization transistor) fabricated in advanced Fully Depleted Silicon On Insulator (FDSOI) 28 nm technology with Ultra-Thin Body and Buried Oxide (UTBB). It is a recent sharp-switching device that achieves remarkable performance in terms of leakage current and triggering control. The device features an extremely sharp on-switch, an adjustable triggering voltage (VON), and is considered for Electro-Static Discharge (ESD) protection. The operation principle relies on the modulation of electrons and holes injection barriers. Experimental results show the effect of low and high temperature on the output characteristics, triggering voltage and leakage current.

  10. Analytical modeling and numerical simulations of the thermal behavior of trench-isolated bipolar transistors on SOI substrates

    Science.gov (United States)

    Marano, I.; d'Alessandro, V.; Rinaldi, N.

    2008-05-01

    The thermal behavior of trench-isolated structures on SOI (silicon-on-insulator) substrates is analyzed. Detailed 3-D numerical simulations have been performed to investigate the impact of all technological and material parameters of interest. A novel analytical model for the temperature field is proposed, which is based on the reduction of the domain under analysis to a silicon rectangular parallelepiped with convective boundary conditions at lateral and bottom faces. An extensive comparison with numerical results proves that the model is extremely accurate in the overall parameter range, and can be adopted for a fast evaluation of the thermal resistance of a trench SOI device as well as of the temperature gradients within the silicon island surrounded by trenches and buried oxide.

  11. 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.

  12. Novel Si ion implantation technique for improving the radiation hardness of SOI pseudo-MOS transistor

    Science.gov (United States)

    Zhang, Yanwei; Huang, Huixiang; Bi, Dawei; Tang, Minghua; Zhang, Zhengxuan

    2014-01-01

    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.

  13. 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.

  14. 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

    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...... 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...... methods (each with N=3) revealed that the oxygen uptake of sandeel buried for 6-7 h was 40-50% of previous estimates on resting respirometry of non-buried fish, indicating lower O(2) requirements during burial on a diurnal timescale. Buried fish exposed to decreasing oxygen tensions gradually approached...

  15. 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...

  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. Buried structure for increasing fabrication performance of micromaterial by electromigration

    Science.gov (United States)

    Kimura, Yasuhiro; Saka, Masumi

    2016-06-01

    The electromigration (EM) technique is a physical synthetic growth method for micro/nanomaterials. EM causes atomic diffusion in a metal line by high-density electron flows. The intentional control of accumulation and relaxation of atoms by EM can lead to the fabrication of a micro/nanomaterial. TiN passivation has been utilized as a component of sample in the EM technique. Although TiN passivation can simplify the cumbersome processes for preparing the sample, the leakage of current naturally occurs because of the conductivity of TiN as a side effect and decreases the performance of micro/nanomaterial fabrication. In the present work, we propose a buried structure, which contributes to significantly decreasing the current for fabricating an Al micromaterial by confining the current flow in the EM technique. The fabrication performance was evaluated based on the threshold current for fabricating an Al micromaterial using the buried structure and the previous structure with the leakage of current.

  18. 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.

  19. 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

  20. 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

  1. 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...

  2. 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.

  3. 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.

  4. 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.

  5. Direct Measurement of the Band Structure of a Buried Two-Dimensional Electron Gas

    DEFF Research Database (Denmark)

    Miwa, Jill; Hofmann, Philip; Simmons, Michelle Y.;

    2013-01-01

    We directly measure the band structure of a buried two dimensional electron gas (2DEG) using angle resolved photoemission spectroscopy. The buried 2DEG forms 2 nm beneath the surface of p-type silicon, because of a dense delta-type layer of phosphorus n-type dopants which have been placed there...

  6. STUDY ON EXTRACTING METHODS OF BURIED GEOLOGICAL INFORMATION IN HUAIBEI COAL FIELD

    Institute of Scientific and Technical Information of China (English)

    王四龙; 赵学军; 凌贻棕; 刘玉荣; 宁书年; 侯德文

    1999-01-01

    It is discussed features and the producing mechanism of buried geological information in geological, geophysical and remote sensing data in Huaibei coal field, and studied the methods extracting buried tectonic and igneous rock information from various geological data using digital image processing techniques.

  7. The buried points on the Julia sets of rational and entire functions

    Institute of Scientific and Technical Information of China (English)

    乔建永

    1995-01-01

    For rational functions it is proved that the Julia set contains buried components whenever the Julia set is disconnected and the Fatou set has no completely invariant component. For transcendental entire functions of finite type it is proved that the Julia set contains unbounded continua of buried points whenever the Fatou set is disconnected.

  8. Numerical Modeling of Mechanical Behavior for Buried Steel Pipelines Crossing Subsidence Strata.

    Directory of Open Access Journals (Sweden)

    J Zhang

    Full Text Available 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.

  9. Efficient calculation of broadband acoustic scattering from a partially, obliquely buried cylinder

    NARCIS (Netherlands)

    Nijhof, M.J.J.; Espana, A.; Williams, K.

    2013-01-01

    An efficient model for the Target In Environment Response (TIER) of buried/half buried, mine-like objects and UXOs is essential for the development and training of automatic target detection and classification methods and for use in sonar performance prediction models. For instance, to investigate t

  10. 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.

  11. 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

  12. 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.

  13. Analysis of buried interfaces in multilayer mirrors using grazing incidence extreme ultraviolet reflectometry near resonance edges.

    Science.gov (United States)

    Sertsu, M G; Nardello, M; Giglia, A; Corso, A J; Maurizio, C; Juschkin, L; Nicolosi, P

    2015-12-10

    Accurate measurements of optical properties of multilayer (ML) mirrors and chemical compositions of interdiffusion layers are particularly challenging to date. In this work, an innovative and nondestructive experimental characterization method for multilayers is discussed. The method is based on extreme ultraviolet (EUV) reflectivity measurements performed on a wide grazing incidence angular range at an energy near the absorption resonance edge of low-Z elements in the ML components. This experimental method combined with the underlying physical phenomenon of abrupt changes of optical constants near EUV resonance edges enables us to characterize optical and structural properties of multilayers with high sensitivity. A major advantage of the method is to perform detailed quantitative analysis of buried interfaces of multilayer structures in a nondestructive and nonimaging setup. Coatings of Si/Mo multilayers on a Si substrate with period d=16.4  nm, number of bilayers N=25, and different capping structures are investigated. Stoichiometric compositions of Si-on-Mo and Mo-on-Si interface diffusion layers are derived. Effects of surface oxidation reactions and carbon contaminations on the optical constants of capping layers and the impact of neighboring atoms' interactions on optical responses of Si and Mo layers are discussed. PMID:26836858

  14. 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.

  15. 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-...

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. The Challenging Buried Bumper Syndrome after Percutaneous Endoscopic Gastrostomy

    Directory of Open Access Journals (Sweden)

    Ibrahim Afifi

    2016-05-01

    Full Text Available 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. Surface wave propagation effects on buried segmented pipelines

    Institute of Scientific and Technical Information of China (English)

    Peixin Shi

    2015-01-01

    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. An EM Modeling for Rescue System Design of Buried People

    Directory of Open Access Journals (Sweden)

    A. De Leo

    2015-01-01

    Full Text Available The development of a rescue system for buried persons is a subject of growing importance in case of occurrence of natural disasters such as earthquake, landslides, or avalanches. In this paper a fully analytical model has been developed to get some fundamental a priori design characteristics. The proposed system is based on the detection of the victim movements due to its respiratory activity: in particular, when an electromagnetic (EM wave impinges on a human body, the analysis of the reflected wave parameters such as amplitude, frequency, phase, or delay time allows for the detection of the breathing frequency. The model is simple on purpose because the great uncertainty concerning the characterization of many environmental parameters of a general situation makes a very detailed model useless. However, it is accurate enough to provide useful information about system design, filling the gap in the literature concerning the electromagnetic formulation of such kinds of problems. A system prototype was built using laboratory equipment to experimentally validate the model, and subsequently breathing frequency measurements were carried on, both in a lossless laboratory environment and in a lossy realistic scenario.

  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. 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.

  12. 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

  13. 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.

  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. The Activity of Liaocheng-Lankao Buried Fault During the Quaternary——An Important Buried Active Fault in the Eastern China Plain

    Institute of Scientific and Technical Information of China (English)

    Xiang Hongfa; Wang Xuechao; Hao Shujian; Zhang Hui; Guo Shunmin; Li Jinzhao; Li Hongwu; Lin Yuanwu; Zhang Wanxia

    2001-01-01

    On the basis of locating by the geochemical prospecting, shallow seismic sounding, drilling,geological profiling, and neogeochronological dating, we first found out the dislocation amount along the Liaocheng-Lankao buried fault since the Quaternary and the age of its latest activity phase and determined that the upper break point by the fault dislocation reaches 20 m below the surface. The latest activity phase was in the early Holocene and the fault is a shallow-buried active fault. An average dislocation rate along the fault is 0.12 mm/a since the Quaternary.Thus, it is a buried active fault with intermediate to strong movement strength in the eastern China.

  16. 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)

  17. [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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 2004 American Burying Beetle Annual Report - Pond Creek National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Survey efforts for the endangered American Burying Beetle at Pond Creek NWR in 2004 are reported from 14 sampling locations on the refuge. American buring beetle...

  3. Molecular phylogeny of the burying beetles (Coleoptera: Silphidae: Nicrophorinae).

    Science.gov (United States)

    Sikes, Derek S; Venables, Chandra

    2013-12-01

    Burying beetles (Silphidae: Nicrophorus) are well-known for their monopolization of small vertebrate carcasses in subterranean crypts and complex biparental care behaviors. They have been the focus of intense behavioral, ecological, and conservation research since the 1980s yet no thorough phylogenetic estimate for the group exists. Herein, we infer relationships, test past hypotheses of relationships, and test biogeographic scenarios among 55 of the subfamily Nicrophorinae's currently valid and extant 72 species. Two mitochondrial genes, COI and COII, and two nuclear genes, the D2 region of 28S, and the protein coding gene CAD, provided 3,971 nucleotides for 58 nicrophorine and 5 outgroup specimens. Ten partitions, with each modeled by GTR+I+G, were used for a 100 M generation MrBayes analysis and maximum likelihood bootstrapping with Garli. The inferred Bayesian phylogeny was mostly well-resolved with only three weak branches of biogeographic relevance. The common ancestor of the subfamily and of the genus Nicrophorus was reconstructed as Old World with four separate transitions to the New World and four reverse colonizations of the Old World from the New. Divergence dating from analysis with BEAST indicate the genus Nicrophorus originated in the Cretaceous, 127-99 Ma. Most prior, pre-cladistic hypotheses of relationships were strongly rejected while most modern hypotheses were largely congruent with monophyletic groups in our estimated phylogeny. Our results reject a recent hypothesis that Nicrophorus morio Gebler, 1817 (NEW STATUS as valid species) is a subspecies of N. germanicus (L., 1758). Two subgenera of Nicrophorus are recognized: NecroxenusSemenov-Tian-Shanskij, 1933, and NicrophorusFabricius, 1775.

  4. 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

  5. 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

  6. Study of Controll over Karstification of Buried Carbonate Hill Reservoir in Renqiu Oilfield

    Institute of Scientific and Technical Information of China (English)

    于俊吉; 韩宝平; 罗承建

    2004-01-01

    Based on boreholes and dynamic development data, the control over karstification of buried carbonate hill reservoir in Renqiu oil field was studied. The result shows that 1) Karstific caves, fissures, and pores in dolomite of Wumishan Formation are the most important reservoir voids, 2) the barrier of argillaceous dolomite can result in the existence of residual oil areas under oil-water interface, and 3) the mosores located on the surface of buried hill are also potential areas of residual oil.

  7. 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.

  8. Seismic fragility analysis of buried steel piping at P, L, and K reactors

    Energy Technology Data Exchange (ETDEWEB)

    Wingo, H.E.

    1989-10-01

    Analysis of seismic strength of buried cooling water piping in reactor areas is necessary to evaluate the risk of reactor operation because seismic events could damage these buried pipes and cause loss of coolant accidents. This report documents analysis of the ability of this piping to withstand the combined effects of the propagation of seismic waves, the possibility that the piping may not behave in a completely ductile fashion, and the distortions caused by relative displacements of structures connected to the piping.

  9. 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...

  10. 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...

  11. 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)

  12. 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

  13. 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.

  14. Enforced water drinking induces changes in burying behavior and social interaction test in rats.

    Science.gov (United States)

    Saldívar-González, J A; Hernández-León, M J; Mondragón-Ceballos, R

    1996-09-01

    The effect of water deprivation and water intake on experimental anxiety in rats was tested using burying behavior (BB) and social interaction (SI) anxiety paradigms. Two groups of animals were studied: a control group with free access to water, and a 72-h water-deprived experimental group. Anxiety was studied in a water-deprived group or following a 10-min period of ad lib water drinking. An increase in the mean time of defensive burying in animals deprived for 72 h was observed, whereas an important reduction occurred in the levels of burying behavior immediately after the animals were allowed to drink ad lib for 10 min. These results suggest that the observed increase in defensive burying in the water-deprived animals represents an anxiogenic effect, whereas the decrease in this behavior in water-satiated animals is considered an anxiolytic action. The temporal course of reduction in burying behavior, observed after water drinking, revealed that the anxiolytic action lasts 5 min, whereas 15-30 min after drinking, burying behavior levels were similar to those in the control group. In the social interaction experiment a partial anxiogenic/anxiolytic effect of water deprivation and water intake was observed. The adaptive meaning of anxiogenic and anxiolytic changes linked to consummatory behaviors in rats is discussed on the basis of behavioral and biochemical data.

  15. Tunable filter based on silicon-on-insulator microring resonator%SoI基微环谐振可调谐滤波器

    Institute of Scientific and Technical Information of China (English)

    姜宏伟; 吴远大

    2011-01-01

    采用电子束光刻和ICP刻蚀等工艺制作出绝缘体上Si(SoI)基纳米线波导微环谐振(MRR)滤波器,波导截面尺寸为300 nm×320 nm,微环半径为5 μm.测试结果表明,器件的自由频谱宽度(FSR)为16.8nm,1.55μm波长附近的消光比(ER)为18.1 dB.通过对MRR滤波器进行热光调制,在21.4~60.0℃温度范围内实现了4.8 nm波长范围的可调谐滤波特性,热光调谐效率达到0.12nm/℃.%Microring-resonator filters are fabricated by E-beam photolithography and inductive-coupled-plasma(ICP) etching technology. The cross-section size of the strip waveguides is 300 nm×320 ran,and the bending radius of the microring is 5 fun. The measured results show that the free spectral range (FSR) and extinction ratio (ER) at the wavelength of 1550 nm are 16. 8 nm and 18.1 dB,respectively. After thermo-optic modulation, the tunable filter wavelength range reaches 4. 8 nm,and the tuning efficiency is 0.12 nm /℃.

  16. 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...

  17. 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.

  18. A Laboratory Project on the Theory, Fabrication, and Characterization of a Silicon-on-Insulator Micro-Comb Drive Actuator with Fixed-Fixed Beams

    Science.gov (United States)

    Abbas, K.; Leseman, Z. C.

    2012-01-01

    A laboratory course on the theory, fabrication, and characterization of microelectromechanical systems (MEMS) devices for a multidisciplinary audience of graduate students at the University of New Mexico, Albuquerque, has been developed. Hands-on experience in the cleanroom has attracted graduate students from across the university's engineering…

  19. 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.

  20. Reconstruction of buried objects embedded in circular opaque structures

    Science.gov (United States)

    Persico, Raffaele; Gennarelli, Gianluca; Soldovieri, Francesco

    2014-05-01

    This contribution deals with the ground penetrating radar imaging of targets embedded in a visually opaque circular structure. The problem has practical relevance in civil engineering and archeological prospections, where structures of interest such as columns or pillars may have to be inspected in non-invasive way in order to detect the possible presence of anomalies (e.g. cracks, water infiltrations, and so on). In this framework, we investigate the possibility to inspect the circular region of interest thanks to a radar system composed by two antennas that are in contact with the structure and rotate simultaneously around it in order to illuminate and measure the field scattered by buried objects from multiple directions. Two different measurement strategies are examined. The first one is the multimonostatic configuration where the backscattered signal is collected by the transmitting antenna itself, as it moves along the circular observation line. The second acquisition strategy is the multibistatic one, with the transmitting and receiving antennas shifted by a constant angular offset of ninety degrees as they move around the column. From the mathematical viewpoint, the imaging problem is formulated as a linear inverse scattering one holding under Born approximation [1]. Furthermore, the Green's function of a homogeneous medium [2] is used to simplify the evaluation of the kernel of the integral equation. The inverse problem is then solved via the Truncated Singular Value Decomposition algorithm [3] in order to obtain a regularized solution. Tomographic reconstructions based on full-wave synthetic data generated by the Finite Difference Time Domain code GPRmax2D [4] are shown to assess the effectiveness of the reconstruction process. REFERENCES [1] W. C. Chew, Waves and fields in inhomogeneous media, IEEE Press, 1995. [2] R. F. Harrington, Time harmonic electromagnetic waves, McGraw-Hill, New York, USA, 1961. [3] M. Bertero and P. Boccacci, Introduction to

  1. Special bedrock buried hill and the reservoiring process in Qijia-Yitong basin in northeastern China

    Institute of Scientific and Technical Information of China (English)

    Zhenlin CHEN; Hongfu YIN; Hongbo MIAO; Yuchao QIU; Yu ZOU

    2011-01-01

    The bedrock buried hill is a mountainous peak formed by the arching up of the basement rocks in a sedimentary basin.The mountainous peak could be the ancient buried hill,known as buried-hill drape structure,present before the formation of sedimentary cover.In contrast,the late-formed buried hill comes into being after the deposition of the sedimentary cover due to the fold,fracture,volcanic eruption and other tectonic events in later stages.No matter what type of buried-hills,the reservoiring is comparable,with the dissolved pores formed by weathering and leaching of bedrocks as the reservoir,and the overlying sedimentary rocks as the source rocks and cover rocks.These are known as ancient reservoir but newbom sources.We present here,however,a different situation of the buried hill in Yitong basin in northeastern China.The bedrock in Yitong basin is the Yanshanian granite,which occurs as a sill underlain by Paleozoic marine strata of low electric resistivity.A rightlateral strike-slip extrusion of Yitong basin in Himalayan period leads to the diapiric ascent of the Lower Paleozoic argillite,which in turn causes the arching up of the granite bedrock to form the buried hill.It is concluded,on the basis of drill No.Chang 37,that the natural gas is sourced from Carboniferous-Permian argillite,and reservoirs in the cracks developed beneath 300m of the granite sill,with the upper part of granite as the cover.

  2. 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.

  3. 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.

  4. Real-time corrosion control system for cathodic protection of buried pipes for nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Tae; Kim, Hae Woong; Kim, Young Sik [School of Materials Science and Engineering, Andong National University, Andong (Korea, Republic of); Chang, Hyun Young; Lim, Bu Taek; Park, Heung Bae [Power Engineering Research Institute, KEPCO Engineering and Construction Company, Seongnam (Korea, Republic of)

    2015-02-15

    Since the operation period of nuclear power plants has increased, the degradation of buried pipes gradually increases and recently it seems to be one of the emerging issues. Maintenance on buried pipes needs high quality of management system because outer surface of buried pipe contacts the various soils but inner surface reacts with various electrolytes of fluid. In the USA, USNRC and EPRI have tried to manage the degradation of buried pipes. However, there is little knowledge about the inspection procedure, test and manage program in the domestic nuclear power plants. This paper focuses on the development and build-up of real-time monitoring and control system of buried pipes. Pipes to be tested are tape-coated carbon steel pipe for primary component cooling water system, asphalt-coated cast iron pipe for fire protection system, and pre-stressed concrete cylinder pipe for sea water cooling system. A control system for cathodic protection was installed on each test pipe which has been monitored and controlled. For the calculation of protection range and optimization, computer simulation was performed using COMSOL Multiphysics (Altsoft co.)

  5. 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

    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...... by electrochemical deposition at a rate of up to 10 mm per min. With the newly developed process, void-free, superconformal Cu-filling of the laser-cut grooves was observed by scanning electron microscopy and focused ion beam techniques. The Cu microstructure in grooves showed both bottom and 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...

  6. 3D Characteristic Diagram of Acoustically Induced Surface Vibration with Different Landmines Buried

    Institute of Scientific and Technical Information of China (English)

    吴智强; 张燕丽; 王驰; 朱俊; 徐文文; 袁志文

    2016-01-01

    The 3Dcharacteristic diagram of acoustically induced surface vibration was employed to study the influence of different buried landmines on the acoustic detection signal. By using the vehicular experimental system for acoustic landmine detection and the method of scanning detection, the 3D characteristic diagrams of surface vibration were measured when different objects were buried underground, including big plastic landmine, small plastic landmine, big metal landmine and bricks. The results show that, under the given conditions, the surface vi-bration amplitudes of big plastic landmine, big metal landmine, small plastic landmine and bricks decrease in turn. The 3D characteristic diagrams of surface vibration can be used to further identify the locations of buried land-mines.

  7. New CMOS compatible super-junction LDMOST with n-type buried layer

    Institute of Scientific and Technical Information of China (English)

    Duan Bao-Xing; Zhang Bo; Li Zhao-Ji

    2007-01-01

    A new super-junction lateral double diffused MOSFET (LDMOST) structure is designed with n-type charge compensation layer embedded in the p--substrate near the drain to suppress substrate-assisted depletion effect that results from the compensating charges imbalance between the pillars in the n-type buried layer. A high electric field peak is introduced in the surface by the pn junction between the p--substrate and n-type buried layer, which given rise to a more uniform surface electric field distribution by modulation effect. The effect of reduced bulk field (REBULF)is introduced to improve the vertical breakdown voltage by reducing the high bulk electric field around the drain. The new structure features high breakdown voltage, low on-resistance and charges balance in the drift region due to n-type buried layer.

  8. Testing MODFLOW-LGR for simulating flow around Buried Quaternary valleys - synthetic test cases

    DEFF Research Database (Denmark)

    Vilhelmsen, Troels Norvin; Christensen, Steen

    In Denmark the water supply is entirely based on ground water. In some parts of the country these resources are found in buried quaternary tunnel valleys. Intensive mapping has shown that the valleys typically have a complex internal hydrogeology with multiple cut and ­fill structures...... 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...

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. Characteristics and genetic mechanism of deep-buried clastic eureservoir in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Systematic researches to the clastic reservoirs in various types and various geological ages basins in China indicate that the present burial depth of deep buried clastic eureservoir ranges from 3000 to 6000 m,and its geological ages from Paleozoic,Mesozoic to Cenozoic. It mainly deposited in delta (including braid delta,fan delta,normal delta),river,also shore,shallow lake,gravity flow channel and turbidity fan facies. The quartzose sandstone is the main reservoir rock of deep-buried clastic eureservoir in the shore facies in Paleozoic,but the arenite and arkose sandstones are the main reservoir rock types in delta,river,shallow lake and gravity flow facies in Mesozoic and Cenozoic. The porosity of most of deep-buried clastic eureservoir is more than 10% and permeability more than 10×10?3 μm2. The forma-tion of the deep-buried eureservoir was related to the paleotectonics,paleotemperature,sedimentary environment,the deep dissolution caused by organic acid or carbonic acid,burial style,the abnormal high pore fluid pressure,early hydrocarbon charging,gyprock sealing,hot convective fluid flow and the mode of sand-mud interbedded,etc. The paleotectonics controls the burial style of sandstones,and the paleotemperature controls the diagenesis process. The sedimentary environment is the precondi-tion and foundation,the dissolution is the direct reason to generate the deep buried clastic eureservoir. The abnormal high pore fluid pressure,gyprock sealing,the mode of sand-mud interbedded,early hy-drocarbon charging and the structure fractures were the assistant factors of generating the deep buried clastic eureservoir.

  14. 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

  15. Latex-modified grouts for in-situ stabilization of buried transuranic/mixed waste

    Energy Technology Data Exchange (ETDEWEB)

    Allan, M.L.

    1996-06-01

    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.

  16. Experimental Study of Surface Detection of Gas Pipeline Buried in Soil

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Pipeline is a key segment in the transportation of city gas and its safety affects the safety of industrial and domestic application. The characteristics of Shi Dongkou east gas steel pipeline buried in soil were discussed and its parameters related to safety were measured, including the state of anticorrosive layer, the soil resistivity,the natural potential and the protective potential of gas pipeline. The experimental results were confirmed by excavating, which are of value to the knowledge of the gas pipeline buried in soil in Shanghai. The experimental data were analyzed which provide the scientific basis for the assurance of the gas pipeline safety and the reparation of anticorrosivelayer.

  17. 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...

  18. 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)

  19. 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

  20. 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.

  1. 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...

  2. Window into Sediment-Buried Basement Biosphere: Fluid Sampling from CORK Observatory Seafloor Platforms, Juan de Fuca Ridge Flanks

    Science.gov (United States)

    Cowen, J. P.; Lin, H.; Rappe, M.; Jungbluth, S.; Glazer, B. T.; Matzinger, M.; Amend, J. P.; Boettger, J.

    2010-12-01

    Studies of the deep basement biosphere are technologically challenging, requiring complementary approaches to provide sufficient access to allow precision analyses and experimentation. Our NSF-funded ‘Microbial Observatory’ has focused on IODP Circulation Obviating Retrofit Kit (CORK) observatories to obtain pristine samples of fluids from sediment-buried basement environments. We have developed instruments and samplers to interface with CORK fluid delivery lines, including a ROV/HOV-borne Mobile Pumping System and autonomous (e.g., GeoMICROBE) instrument sensor/sampler systems. These systems are providing high quality (e.g., depleted Mg++, Ridge, for geochemical and microbial studies. Relative to bottom seawater, these fluids are also depleted in O2, SO42-, PO43-, NO3- and NO2-, while enriched in NH4+, H2S, Mn and Fe. In situ voltammetric analyses obtained during sample collection, revealed the presence of micromolar levels of sulfide (0.5 µm) in the fluids. Dissolved organic carbon in basement fluids is about half that of local bottom seawater, low molecular weight organic acids are below detection limits, while total amino acids are also low in concentration, but the relative abundance of specific amino acids varies from that of bottom seawater. Overall, the sediment-buried basement environments appears to be organic-carbon depleted and low energy, yet still dynamic. The microbial communities from CORK 1301A (47deg 45N, 127deg 45W) in consecutive years are heterogeneous, but share common groups. Different CORKs sampled a decade apart share major lineages, consistent with hydrogeologic connectivity. Samples collected from a new CORK installation at borehole 1026B contain a subset of members found a decade previously from an older style CORK at the same site. Communities retrieved from the CORK at 1025C (47deg 53N, 128deg 39W), in 1.4 My ridge flank basement, possessed groups in common with fluids from 3.5 My ridge flanks (1301A). Microbial biomass is low

  3. Electronic structure of (In,Mn)As quantum dots buried in GaAs investigated by soft-x-ray ARPES.

    Science.gov (United States)

    Bouravleuv, A D; Lev, L L; Piamonteze, C; Wang, X; Schmitt, T; Khrebtov, A I; Samsonenko, Yu B; Kanski, J; Cirlin, G E; Strocov, V N

    2016-10-21

    Electronic structure of a molecular beam epitaxy-grown system of (In,Mn)As quantum dots (QDs) buried in GaAs is explored with soft-x-ray angle-resolved photoelectron spectroscopy (ARPES) using photon energies around 1 keV. This technique, ideally suited for buried systems, extends the momentum-resolving capabilities of conventional ARPES with enhanced probing depth as well as elemental and chemical state specificity achieved with resonant photoexcitation. The experimental results resolve the dispersive energy bands of the GaAs substrate buried in ∼2 nm below the surface, and the impurity states (ISs) derived from the substitutional Mn atoms in the (In,Mn)As QDs and oxidized Mn atoms distributed near the surface. An energy shift of the Mn ISs in the QDs compared to (In,Mn)As DMS is attributed to the band offset and proximity effect at the interface with the surrounding GaAs. The absence of any ISs in the vicinity of the VBM relates the electron transport in (In,Mn)As QDs to the prototype (In,Mn)As diluted magnetic semiconductor. The SX-ARPES results are supported by measurements of the shallow core levels under variation of probing depth through photon energy. X-ray absorption measurements identify significant diffusion of interstitial Mn atoms out of the QDs towards the surface, and the role of magnetic circular dichroism is to block the ferromagnetic response of the (In,Mn)As QDs. Possible routes are drawn to tune the growth procedure aiming at practical applications of the (In,Mn)As based systems.

  4. Electronic structure of (In,Mn)As quantum dots buried in GaAs investigated by soft-x-ray ARPES.

    Science.gov (United States)

    Bouravleuv, A D; Lev, L L; Piamonteze, C; Wang, X; Schmitt, T; Khrebtov, A I; Samsonenko, Yu B; Kanski, J; Cirlin, G E; Strocov, V N

    2016-10-21

    Electronic structure of a molecular beam epitaxy-grown system of (In,Mn)As quantum dots (QDs) buried in GaAs is explored with soft-x-ray angle-resolved photoelectron spectroscopy (ARPES) using photon energies around 1 keV. This technique, ideally suited for buried systems, extends the momentum-resolving capabilities of conventional ARPES with enhanced probing depth as well as elemental and chemical state specificity achieved with resonant photoexcitation. The experimental results resolve the dispersive energy bands of the GaAs substrate buried in ∼2 nm below the surface, and the impurity states (ISs) derived from the substitutional Mn atoms in the (In,Mn)As QDs and oxidized Mn atoms distributed near the surface. An energy shift of the Mn ISs in the QDs compared to (In,Mn)As DMS is attributed to the band offset and proximity effect at the interface with the surrounding GaAs. The absence of any ISs in the vicinity of the VBM relates the electron transport in (In,Mn)As QDs to the prototype (In,Mn)As diluted magnetic semiconductor. The SX-ARPES results are supported by measurements of the shallow core levels under variation of probing depth through photon energy. X-ray absorption measurements identify significant diffusion of interstitial Mn atoms out of the QDs towards the surface, and the role of magnetic circular dichroism is to block the ferromagnetic response of the (In,Mn)As QDs. Possible routes are drawn to tune the growth procedure aiming at practical applications of the (In,Mn)As based systems. PMID:27631689

  5. Electronic structure of (In,Mn)As quantum dots buried in GaAs investigated by soft-x-ray ARPES

    Science.gov (United States)

    Bouravleuv, A. D.; Lev, L. L.; Piamonteze, C.; Wang, X.; Schmitt, T.; Khrebtov, A. I.; Samsonenko, Yu B.; Kanski, J.; Cirlin, G. E.; Strocov, V. N.

    2016-10-01

    Electronic structure of a molecular beam epitaxy-grown system of (In,Mn)As quantum dots (QDs) buried in GaAs is explored with soft-x-ray angle-resolved photoelectron spectroscopy (ARPES) using photon energies around 1 keV. This technique, ideally suited for buried systems, extends the momentum-resolving capabilities of conventional ARPES with enhanced probing depth as well as elemental and chemical state specificity achieved with resonant photoexcitation. The experimental results resolve the dispersive energy bands of the GaAs substrate buried in ∼2 nm below the surface, and the impurity states (ISs) derived from the substitutional Mn atoms in the (In,Mn)As QDs and oxidized Mn atoms distributed near the surface. An energy shift of the Mn ISs in the QDs compared to (In,Mn)As DMS is attributed to the band offset and proximity effect at the interface with the surrounding GaAs. The absence of any ISs in the vicinity of the VBM relates the electron transport in (In,Mn)As QDs to the prototype (In,Mn)As diluted magnetic semiconductor. The SX-ARPES results are supported by measurements of the shallow core levels under variation of probing depth through photon energy. X-ray absorption measurements identify significant diffusion of interstitial Mn atoms out of the QDs towards the surface, and the role of magnetic circular dichroism is to block the ferromagnetic response of the (In,Mn)As QDs. Possible routes are drawn to tune the growth procedure aiming at practical applications of the (In,Mn)As based systems.

  6. Y chromosomal and sex effects on the behavioral stress response in the defensive burying test in wild house mice

    NARCIS (Netherlands)

    Sluyter, F; Korte, SM; Van Baal, GCM; De Ruiter, AJH; Van Oortmerssen, GA

    1999-01-01

    Genetically selected short attack latency (SAL) and long attack latency (LAL) male wild house mice behave differently in the defensive burying test. When challenged, SAL males respond actively with more time spent on defensive burying, whereas LAL males are more passive with more time remaining immo

  7. Influence of Zn Diffusion on Bandwidth and Extinction in MQW Electroabsorption Modulators Buried with Semi-Insulating InP

    Institute of Scientific and Technical Information of China (English)

    Takayuki Yamanaka; Hideki Fukano; Ken Tsuzuki; Munehisa Tamura; Ryuzo Iga; Matsuyuki Ogasawara; Yasuhiro Kondo; Tadashi Saitoh

    2003-01-01

    A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation.

  8. 49 CFR 192.455 - External corrosion control: Buried or submerged pipelines installed after July 31, 1971.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.455 External corrosion control: Buried or... against external corrosion, including the following: (1) It must have an external protective...

  9. 49 CFR 192.457 - External corrosion control: Buried or submerged pipelines installed before August 1, 1971.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External corrosion control: Buried or submerged... SAFETY STANDARDS Requirements for Corrosion Control § 192.457 External corrosion control: Buried or... areas in which active corrosion is found: (1) Bare or ineffectively coated transmission lines. (2)...

  10. 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...

  11. Early Monitoring of the Viability of the Buried Intrathoracic Omental Flap: A Feasibility Study

    NARCIS (Netherlands)

    J.J. van Wingerden; J.M.P. Collins; E.H. Coret; P.J.J. Schröder

    2010-01-01

    Purpose. The value of mobile, high-resolution gray-scale and color Doppler ultrasonography (US) in the immediate postoperative, intensive care setting for monitoring the buried flap and vascular pedicle of the laparoscopic or transdiaphragmatic harvested omentum for intrathoracic reconstruction was

  12. Structure of the Buried Metal-Molecule Interface in Organic Thin Film Devices

    DEFF Research Database (Denmark)

    Hansen, Christian Rein; Sørensen, Thomas Just; Glyvradal, Magni;

    2009-01-01

    . By 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...

  13. 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

    at 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...

  14. 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.

  15. A shear wave ground surface vibration technique for the detection of buried pipes

    Science.gov (United States)

    Muggleton, J. M.; Papandreou, B.

    2014-07-01

    A major UK initiative, entitled 'Mapping the Underworld' aims to develop and prove the efficacy of a multi-sensor device for accurate remote buried utility service detection, location and, where possible, identification. One of the technologies to be incorporated in the device is low-frequency vibro-acoustics; the application of this technology for detecting buried infrastructure, in particular pipes, is currently being investigated. Here, a shear wave ground vibration technique for detecting buried pipes is described. For this technique, shear waves are generated at the ground surface, and the resulting ground surface vibrations measured. Time-extended signals are employed to generate the illuminating wave. Generalized cross-correlation functions between the measured ground velocities and a reference measurement adjacent to the excitation are calculated and summed using a stacking method to generate a cross-sectional image of the ground. To mitigate the effects of other potential sources of vibration in the vicinity, the excitation signal can be used as an additional reference when calculating the cross-correlation functions. Measurements have been made at two live test sites to detect a range of buried pipes. Successful detection of the pipes was achieved, with the use of the additional reference signal proving beneficial in the noisier of the two environments.

  16. 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.

  17. 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.

  18. Fourier Array Processing for Buried Victims Detection using Ultra Wide Band Radar with Uncalibrated Sensors

    NARCIS (Netherlands)

    Lidicky, L.

    2008-01-01

    The purpose of this paper is to propose a new way to detect victims buried in or under layers of rubble or debris in case of disasters such as earthquakes, fires or terrorist attacks. The method is based on Fourier Processing and Principal Component Analysis (PCA). It utilizes a moving array of sens

  19. 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

  20. 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.

  1. 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.

  2. Rare earth element distribution and behaviour in buried manganese nodules from the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Banakar, V.K.

    at approximately 225 kyr B.P. The effect of burial is observed only in the depletion of heavy REE (HREE) in a nodule buried at 23.5 cm depth where the environment is suboxic to anoxic. Middle REE (MREE) in the nodules exhibit enrichment over light REE (LREE...

  3. 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.

  4. 1×4 buried optical power splitter fabricated by Tl+-Na+ ion-exchange

    Institute of Scientific and Technical Information of China (English)

    Zigang Zhou (周自刚); Desen Liu (刘德森)

    2003-01-01

    A new 1 × 4 buried optical power splitter with curved Y-junction structure has been successfully designed by a beam propagation method (BPM) software and fabricated by two-step ion-exchange in glass. The optical qualities of the device are favorable in comparison with that obtained with dry etching fabrication techniques.

  5. Scattering from a Buried Circular Cylinder Illuminated by a Three-Dimensional Source

    DEFF Research Database (Denmark)

    Hansen, T.B.; Meincke, Peter

    2002-01-01

    We employ plane and cylindrical wave expansions with the fast Fourier transform to solve scattering problems involving a circular cylinder buried in soil. The illumination is provided by a three-dimensional source located in air above ground. Plane wave expansions describe transmitted and reflected...

  6. Application of forecasting structural cracks technique of 3DMove in Chengdao buried hill

    Institute of Scientific and Technical Information of China (English)

    WU; Shiguo; WANG; Xiuling; JI; Yuxin; LIU; Yuzhen

    2005-01-01

    3DMove software, based on the three-dimension structural model of geologic interpretation, can forecast reservoir cracks from the point of view of formation of the structural geology, and analyze the characteristics of the cracks. 3DMove software dominates in forecasting cracks. We forecast the developments and directions of the cracks in Chengbei buried hill with the application of forecasting technique in 3DMove software, and obtain the chart about strain distributing on top in buried hill and the chart about relative density and orientation and the chart about the analysis of crack unsealing. In Chengbei 30 buried hill zone, north-west and north-east and approximately east-west cracks in Cenozoic are very rich and the main directions in every fault block are different. Forecasting results that are also verified by those of drilling approximately accord with the data from well logging, the case of which shows that the technique has the better ability in forecasting cracks, and takes more effects on exploration and exploitation of crack reservoir beds in ancient buried hill reservoirs.

  7. Oxygen deficiency impacts on burying habitats for lesser sandeel, Ammodytes tobianus, in the inner Danish waters

    DEFF Research Database (Denmark)

    Behrens, Jane; Ærtebjerg, Gunni; Petersen, Jens Kjerulf;

    2009-01-01

    Starting in 1980s, the inner Danish waters have yearly been exposed to seasonal oxygen deficiency (hypoxia). Through spatial–temporal interpolation of monitoring data (1998–2005), we investigated oxygen deficiency impacts on suitable burying habitats for lesser sandeel (Ammodytes tobianus...

  8. 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...

  9. 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.

  10. Towards quantitative three-dimensional characterisation of buried InAs quantum dots

    DEFF Research Database (Denmark)

    Kadkhodazadeh, Shima; Semenova, Elizaveta; Schubert, Martin;

    2011-01-01

    characterisation of surface and buried quantum dots. We highlight some of the challenges involved and introduce a new specimen preparation method for creating needle-shaped specimens that each contain multiple dots and are suitable for both scanning transmission electron microscopy tomography and atom probe...

  11. Novel applications of optical techniques to the study of buried semiconductor interfaces

    Science.gov (United States)

    Wilson, Barbara A.

    1989-01-01

    Detailed electronic and structural information about buried semiconductor interfaces obtained through application of optical techniques is discussed. The measurements described include the determination of band discontinuities, strain, and disorder associated with semiconductor heterointerfaces. The contactless and nondestructive nature of these optical techniques is particularly important for the study of heterointerfaces which are inherently inaccessible to direct electrical or physical contact.

  12. 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.

  13. 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%.

  14. Capturing buried defects in metal interconnections with electron beam inspection system

    Science.gov (United States)

    Xiao, Hong; Jiang, Ximan; Trease, David; Van Riet, Mike; Ramprasad, Shishir; Bhatia, Anadi; Lefebvre, Pierre; Bastard, David; Moreau, Olivier; Maher, Chris; MacDonald, Paul; Campochiaro, Cecelia

    2013-04-01

    In this paper we present a novel mode of electron beam inspection (EBI), entitled super wide optics (SWO) mode, which can effectively detect buried defects in tungsten (W) plugs and copper (Cu) wires. These defects are defects of interest (DOI) to integrated circuit (IC) manufacturers because they are not detectable in optical inspection, voltage contrast (VC) mode EBI or physical mode EBI. We used engineering systems to study two samples, a tungsten chemical mechanical polish (CMP) wafer and a copper CMP wafer with a silicon carbon nitride (SiCN) cap layer. EBI with our novel SWO mode was found to capture many dark defects on these two wafers. Furthermore, defect review with all three EBI modes found some of these dark defects were unique to SWO mode. For verification, physical failure analysis was performed on some SWO-unique DOI. The cross-sectional scanning electron microscope (SEM) images and transmission electron microscope (TEM) images confirmed that the unique DOI were buried voids in W-plugs and copper wire thinning caused by either buried particles or buried particle induced metal trench under-etch. These DOI can significantly increase the resistance of metal interconnects of IC chip and affect the chip yield. This new EBI mode can provide an in-line monitoring solution for these DOI, which does not exist before this study.

  15. 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...

  16. Advanced modeling of thermal NDT problems: from buried landmines to defects in composites

    Science.gov (United States)

    Vavilov, Vladimir P.; Burleigh, Douglas D.; Klimov, Alexey G.

    2002-03-01

    Advanced thermal models that can be used in the detection of buried landmines and the TNDT (thermographic nondestructive testing) of composites are discussed. The interdependence between surface temperature signals and various complex parameters, such as surface and volumetric moisture, the shape of a heat pulse, material anisotropy, etc., is demonstrated.

  17. 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

  18. The development of a ballistic method for simulating fragments from buried explosive devices

    NARCIS (Netherlands)

    Jagt-Deutekom, M.J. van der

    2016-01-01

    No standard scientific methodology currently exists to assess the performance of personal protection equipment (PPE) against secondary debris, such as soil, grit and stones, ejected when a buried improvised explosive device (IED) detonates. Different test methods are used for this evaluation. The PP

  19. 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

  20. Low frequency synthetic aperture sonar for detecting and classifying buried objects

    NARCIS (Netherlands)

    Hunter, A.J.; Vossen, R. van; Quesson, B.A.J.; Colin, M.E.G.D.; Zampolli, M.; Beckers, A.L.D.

    2012-01-01

    Sidescan high-frequency (HF) sonar (i.e., with frequencies higher than 100 kHz) is ideally suited for providing high-resolution images of the seafloor. However, since sound does not penetrate into the sediment at these frequencies, such systems cannot be used for the detection of buried objects, suc

  1. Determination of the electronic density of states near buried interfaces: Application to Co/Cu multilayers

    DEFF Research Database (Denmark)

    Nilsson, A.; Sthör, J.; Wiell, T.;

    1996-01-01

    High-resolution L(3) x-ray absorption and emission spectra of Co and Cu in Co/Cu multilayers are shown to provide unique information on the occupied and unoccupied density of d states near buried interfaces. The d bands of both Co and Cu interfacial layers are shown to be considerably narrowed re...

  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. Low dose effects of a Withania somnifera extract on altered marble burying behavior in stressed mice

    Science.gov (United States)

    Dey, Amitabha; Chatterjee, Shyam Sunder; Kumar, Vikas

    2016-01-01

    Aim: Withania somnifera root (WSR) extracts are often used in traditionally known Indian systems of medicine for prevention and cure of psychosomatic disorders. The reported experiment was designed to test whether low daily oral doses of such extracts are also effective in suppressing marble burying behavior in stressed mice or not. Materials and Methods: Groups of mice treated with 10, 20, or 40 mg/kg daily oral doses of WSR were subjected to a foot shock stress-induced hyperthermia test on the 1st, 5th, 7th, and 10th day of the experiment. On the 11th and 12th treatment days, they were subjected to marble burying tests. Stress response suppressing effects of low dose WSR were estimated by its effects on body weight and basal core temperature of animals during the course of the experiment. Results: Alterations in bodyweight and basal core temperature triggered by repeated exposures to foot shock stress were absent even in the 10 mg/kg/day WSR treated group, whereas the effectiveness of the extract in foot shock stress-induced hyperthermia and marble burying tests increased with its increasing daily dose. Conclusion: Marble burying test in stressed mice is well suited for identifying bioactive constituents of W. somnifera like medicinal plants with adaptogenic, anxiolytic and antidepressant activities, or for quantifying pharmacological interactions between them. PMID:27366354

  4. 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.

  5. 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。

  6. 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

  7. Micro-imaging of buried layers and interfaces in ultrathin films by X-ray reflectivity

    Science.gov (United States)

    Jiang, Jinxing; Hirano, Keiichi; Sakurai, Kenji

    2016-09-01

    X-ray reflectivity is a promising technique for characterizing buried layers and interfaces in ultrathin films because of its ability to probe the electron density profile along the depth in a non-destructive manner. While routine X-ray reflectivity assumes the in-plane uniformity of the sample to be measured, it is also quite important to see buried inhomogeneous/patterned layers and interfaces. The present paper describes the addition of spatial resolution and imaging capability to an X-ray reflectivity technique to visualize surfaces and buried interfaces. To visualize quite wide viewing area size quickly, the image reconstruction scheme has been employed instead of the scanning of microbeam. Though the mathematics is quite close to X-ray computer tomography, the technique gives the image contrast caused by the difference in reflectivity at each in-plane point in the thin film sample. By choosing a grazing angle, the image gives inhomogeneity of X-ray reflectivity at the specific wavevector transfer. With a collimated monochromatic synchrotron X-ray beam of 0.05 mm (H) × 8 mm (V), the intensity profiles of X-ray reflection projections have been taken at many different in-plane rotation angles, from 0° to 180°. We have succeeded in visualizing buried layers and interfaces of the 8 mm dia area with the spatial resolution of better than 20 μm. Because of the brilliance of synchrotron radiation, the typical measuring time is shorter than 1 min. Three analytical cases have been discussed: (i) imaging of a buried layer and an interface covered by a protection layer, (ii) distinguishing different local parts of different thicknesses in an ultrathin film, and (iii) selective imaging of a specific metal in the thin film form.

  8. 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...

  9. Three-dimensional quantitative chemical roughness of buried ZrO{sub 2}/In{sub 2}O{sub 3} interfaces via energy-filtered electron tomography.

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, X. Y.; Kabius, B.; Schreiber, D. K.; Eastman, J. A.; Fong, D. D.; Petford-Long, A. K. (Center for Nanoscale Materials); ( MSD); (Tsinghua Univ.); (Pacific Northwest Nat. Lab.)

    2012-01-01

    The protocol to calculate the chemical roughness from three-dimensional (3-D) data cube acquired by energy-filtered electron tomography has been developed and applied to analyze the 3-D Zr distribution at the arbitrarily shaped interfaces in the ZrO{sub 2}/In{sub 2}O{sub 3} multilayer films. The calculated root-mean-square roughness quantitatively revealed the chemical roughness at the buried ZrO2/In2O3 interfaces, which is the deviation of Zr distribution from the ideal flat interface. Knowledge of the chemistry and structure of oxide interfaces in 3-D provides information useful for understanding changes in the behavior of a model ZrO{sub 2}/In{sub 2}O{sub 3} heterostructure that has potential to exhibit mixed conduction behavior.

  10. Three-Dimensional Quantitative Chemical Roughness Of Buried ZrO2/In2O3 Interfaces Via Energy-Filtered Electron Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, X. Y.; Kabius, B.; Schreiber, Daniel K.; Eastman, J. A.; Fong, D. D.; Petford-Long, Amanda K.

    2012-04-26

    The protocol to calculate the chemical roughness from three-dimensional (3-D) data cube acquired by energy-filtered electron tomography has been developed and applied to analyze the 3-D Zr distribution at the arbitrarily shaped interfaces in the ZrO2/In2O3 multilayer films. The calculated root-mean-square roughness quantitatively revealed the chemical roughness at the buried ZrO2/In2O3 interfaces, which is the deviation of Zr distribution from the ideal flat interface. Knowledge of the chemistry and structure of oxide interfaces in 3-D provides information useful for understanding changes in the behavior of a model ZrO2/In2O3 heterostructure that has potential to exhibit mixed conduction behavior. VC 2012 American Institute of Physics.

  11. Three-dimensional quantitative chemical roughness of buried ZrO2/In2O3 interfaces via energy-filtered electron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, X. Y.; Kabius, Bernd C.; Schreiber, Daniel K.; Eastman, J. A.; Fong, D. D.; Petford-Long, Amanda K.

    2012-04-01

    The protocol to calculate the chemical roughness from three-dimensional (3-D) data cube acquired by energy-filtered electron tomography has been developed and applied to analyze the 3-D Zr distribution at the arbitrarily shaped interfaces in the ZrO{sub 2}/In{sub 2}O{sub 3} multilayer films. The calculated root-mean-square roughness quantitatively revealed the chemical roughness at the buried ZrO{sub 2}/In{sub 2}O{sub 3} interfaces, which is the deviation of Zr distribution from the ideal flat interface. Knowledge of the chemistry and structure of oxide interfaces in 3-D provides information useful for understanding changes in the behavior of a model ZrO{sub 2}/In{sub 2}O{sub 3} heterostructure that has potential to exhibit mixed conduction behavior.

  12. An L-shaped low on-resistance current path SOI LDMOS with dielectric field enhancement

    International Nuclear Information System (INIS)

    A low specific on-resistance (Ron,sp) SOI NBL TLDMOS (silicon-on-insulator trench LDMOS with an N buried layer) is proposed. It has three features: a thin N buried layer (NBL) on the interface of the SOI layer/buried oxide (BOX) layer, an oxide trench in the drift region, and a trench gate extended to the BOX layer. First, on the on-state, the electron accumulation layer forms beside the extended trench gate; the accumulation layer and the highly doping NBL constitute an L-shaped low-resistance conduction path, which sharply decreases the Ron,sp. Second, in the y-direction, the BOX's electric field (E-field) strength is increased to 154 V/μm from 48 V/μm of the SOI Trench Gate LDMOS (SOI TG LDMOS) owing to the high doping NBL. Third, the oxide trench increases the lateral E-field strength due to the lower permittivity of oxide than that of Si and strengthens the multiple-directional depletion effect. Fourth, the oxide trench folds the drift region along the y-direction and thus reduces the cell pitch. Therefore, the SOI NBL TLDMOS structure not only increases the breakdown voltage (BV), but also reduces the cell pitch and Ron,sp. Compared with the TG LDMOS, the NBL TLDMOS improves the BV by 105% at the same cell pitch of 6 μm, and decreases the Ron,sp by 80% at the same BV. (semiconductor devices)

  13. 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

  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. 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.

  16. 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

  17. Prediction Technology of Buried Water-Bearing Structures in Coal Mines Using Transient Electromagnetic Method

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhi-hai; YUE Jian-hua; LIU Shu-cai

    2007-01-01

    Buried water-conducting and water-bearing structures in front of the driving head may easily lead to water bursts in coal mines. Therefore, it is very important for the safety of production to make an accurate and timely forecast about water bursts. Based on the smoke ring effect of transient electromagnetic fields, the principle of transient electromagnetic method used in detecting buried water-bearing structures in coal mines in advance, is discussed. Small multi-turn loop configurations used in coal mines are proposed and a field procedure of semicircular sector scanning is presented. The application of this method in one coal mine indicates that the technology has many advantages compared with others. The method is inexpensive, highly accurate and efficient. Suggestions are presented for future solutions to some remaining problems.

  18. 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.

    2016-09-01

    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.

  19. Buried object detection using handheld WEMI with task-driven extended functions of multiple instances

    Science.gov (United States)

    Cook, Matthew; Zare, Alina; Ho, Dominic K. C.

    2016-05-01

    Many effective supervised discriminative dictionary learning methods have been developed in the literature. However, when training these algorithms, precise ground-truth of the training data is required to provide very accurate point-wise labels. Yet, in many applications, accurate labels are not always feasible. This is especially true in the case of buried object detection in which the size of the objects are not consistent. In this paper, a new multiple instance dictionary learning algorithm for detecting buried objects using a handheld WEMI sensor is detailed. The new algorithm, Task Driven Extended Functions of Multiple Instances, can overcome data that does not have very precise point-wise labels and still learn a highly discriminative dictionary. Results are presented and discussed on measured WEMI data.

  20. The effect of sand composition on the degradation of buried oil.

    Science.gov (United States)

    Fernández-Fernández, Sandra; Bernabeu, Ana M; Rey, Daniel; Mucha, Ana P; Almeida, C Marisa R; Bouchette, Frédéric

    2014-09-15

    The potential effects of the mineralogical composition of sediment on the degradation of oil buried on sandy beaches were investigated. Toward that purpose, a laboratory experiment was carried out with sandy sediment collected along NW Iberian Peninsula beaches, tar-balls from the Prestige oil spill (NW Spain) and seawater. The results indicate that the mineralogical composition is important for the physical appearance of the oil (tar-balls or oil coatings). This finding prompted a reassessment of the current sequence of degradation for buried oil based on compositional factors. Moreover, the halo development of the oil coatings might be enhanced by the carbonate concentration of the sand. These findings open new prospects for future monitoring and management programs for oiled sandy beaches.

  1. Reducing Thermal Losses and Gains With Buried and Encapsulated Ducts in Hot-Humid Climates

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, C. [Steven Winter Associates, Inc., Norwalk, CT (United States); Magee, A. [Steven Winter Associates, Inc., Norwalk, CT (United States); Zoeller, W. [Steven Winter Associates, Inc., Norwalk, CT (United States)

    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.

  2. 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

  3. Breaking the Obscuring Screen: A Resolved Molecular Outflow in a Buried QSO

    CERN Document Server

    Rupke, David

    2013-01-01

    We present Keck laser guide star adaptive optics observations of the nearby buried QSO F08572+3915:NW. We use near-infrared integral field data taken with OSIRIS to reveal a compact disk and molecular outflow using Pa-alpha and H_2 rotational-vibrational transitions at a spatial resolution of 100 pc. The outflow emerges perpendicular to the disk into a bicone of one-sided opening angle 100 degrees up to distances of 400 pc from the nucleus. The integrated outflow velocities, which reach at least -1300 km/s, correspond exactly to those observed in (unresolved) OH absorption, but are smaller (larger) than those observed on larger scales in the ionized (neutral atomic) outflow. These data represent a factor of >10 improvement in the spatial resolution of molecular outflows from mergers/QSOs, and plausibly represent the early stages of the excavation of the dust screen from a buried QSO.

  4. Vertical coupling of laser glass microspheres to buried silicon nitride ellipses and waveguides

    CERN Document Server

    Navarro-Urrios, Daniel; 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 mirror. In the latter case, the input of a strip waveguide is placed on one focus of the ellipse, while a lasing microsphere is placed on top of the other focus. The fabricated elliptical geometry (ellipticity=0.9) presents a light collecting capacity that is 50% greater than that of the standard waveguide coupling configuration and could be further improved by increasing the ellipticity. Moreover, since the dimensions of the spheres are much smaller than those of the ellipses, surface planarization is not required. On th...

  5. Scanning capacitance microscopy registration of buried atomic-precision donor devices

    International Nuclear Information System (INIS)

    We show that a scanning capacitance microscope (SCM) can image buried delta-doped donor nanostructures fabricated in Si via a recently developed atomic-precision scanning tunneling microscopy (STM) lithography technique. A critical challenge in completing atomic-precision nanoelectronic devices is to accurately align mesoscopic metal contacts to the STM defined nanostructures. Utilizing the SCMs ability to image buried dopant nanostructures, we have developed a technique by which we are able to position metal electrodes on the surface to form contacts to underlying STM fabricated donor nanostructures with a measured accuracy of 300 nm. Low temperature (T = 4 K) transport measurements confirm successful placement of the contacts to the donor nanostructures. (paper)

  6. 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

  7. Sequential feature selection for detecting buried objects using forward looking ground penetrating radar

    Science.gov (United States)

    Shaw, Darren; Stone, Kevin; Ho, K. C.; Keller, James M.; Luke, Robert H.; Burns, Brian P.

    2016-05-01

    Forward looking ground penetrating radar (FLGPR) has the benefit of detecting objects at a significant standoff distance. The FLGPR signal is radiated over a large surface area and the radar signal return is often weak. Improving detection, especially for buried in road targets, while maintaining an acceptable false alarm rate remains to be a challenging task. Various kinds of features have been developed over the years to increase the FLGPR detection performance. This paper focuses on investigating the use of as many features as possible for detecting buried targets and uses the sequential feature selection technique to automatically choose the features that contribute most for improving performance. Experimental results using data collected at a government test site are presented.

  8. Measurement of buried undercut structures in microfluidic devices by laser fluorescent confocal microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Li Shiguang; Liu Jing; Nguyen, Nam-Trung; Fang Zhongping; Yoon, Soon Fatt

    2009-11-20

    Measuring buried, undercut microstructures is a challenging task in metrology. These structures are usually characterized by measuring their cross sections after physically cutting the samples. This method is destructive and the obtained information is incomplete. The distortion due to cutting also affects the measurement accuracy. In this paper, we first apply the laser fluorescent confocal microscopy and intensity differentiation algorithm to obtain the complete three-dimensional profile of the buried, undercut structures in microfluidic devices, which are made by the soft lithography technique and bonded by the oxygen plasma method. The impact of material wettability and the refractive index (n) mismatch among the liquid, samples, cover layer, and objective on the measurement accuracy are experimentally investigated.

  9. FEM Analysis of Dynamic Response of Buried Fiber Reinforced Plastic Matrix Pipe under Seismic Load

    OpenAIRE

    Xu Lei; Ye Zhicai; Ren Qingwen; Zhang Lei

    2013-01-01

    Fiber reinforced plastic matrix pipes have been widely used in the field of civil engineering and hydraulic engineering. In general, the existing FEM models used in the seismic analysis of buried pipes do not fully consider the dynamic interaction between pipe and surrounding soil, and most of the models are proposed for homogeneous pipe. Therefore, the existing models cannot be directly applied to the seismic analysis of fiber reinforced plastic matrix pipes with laminated structure. Based o...

  10. Attribute-driven transfer learning for detecting novel buried threats with ground-penetrating radar

    Science.gov (United States)

    Colwell, Kenneth A.; Collins, Leslie M.

    2016-05-01

    Ground-penetrating radar (GPR) technology is an effective method of detecting buried explosive threats. The system uses a binary classifier to distinguish "targets", or buried threats, from "nontargets" arising from system prescreener false alarms; this classifier is trained on a dataset of previously-observed buried threat types. However, the threat environment is not static, and new threat types that appear must be effectively detected even if they are not highly similar to every previously-observed type. Gathering a new dataset that includes a new threat type is expensive and time-consuming; minimizing the amount of new data required to effectively detect the new type is therefore valuable. This research aims to reduce the number of training examples needed to effectively detect new types using transfer learning, which leverages previous learning tasks to accelerate and improve new ones. Further, new types have attribute data, such as composition, components, construction, and size, which can be observed without GPR and typically are not explicitly included in the learning process. Since attribute tags for buried threats determine many aspects of their GPR representation, a new threat type's attributes can be highly relevant to the transfer-learning process. In this work, attribute data is used to drive transfer learning, both by using attributes to select relevant dataset examples for classifier fusion, and by extending a relevance vector machine (RVM) model to perform intelligent attribute clustering and selection. Classification performance results for both the attribute-only case and the low-data case are presented, using a dataset containing a variety of threat types.

  11. Reference standard of penile size and prevalence of buried penis in Japanese newborn male infants.

    Science.gov (United States)

    Matsuo, Nobutake; Ishii, Tomohiro; Takayama, John I; Miwa, Masayuki; Hasegawa, Tomonobu

    2014-01-01

    The present study set forth the reference values for penile size and determined the prevalence of buried penis in Japanese full-term newborns. The stretched penile length was measured and the presence of buried penis was assessed at 1-7 days of age in 547 Japanese full-term newborn infants born between 2008 and 2012 in Tokyo. The stretched penile lengths were compared at 1-12 hours and 1-7 days of age in 63 infants and by two observers in 73 infants to estimate postnatal changes and interobserver variation, respectively. The mean stretched penile length was 3.06 cm (SD, 0.26; 95% confidence interval [CI], 3.04-3.08) and the mean ratio of penile length to body length was 6.24 × 100(-1) (SD, 0.55 × 100(-1)), both of which were significantly smaller than those in Caucasian newborn infants. Buried penis was identified in 20 of 547 infants (3.7%; 95% CI, 2.1-5.2%). The first measurements of penile length at 1-12 hours were significantly smaller than the next measurements at 1-7 days (95% CI of the difference, 0.22-0.34). The 95% CI for the limits of agreement in the penile lengths measured by the two observers was -0.58 to -0.40 for the lower limit and 0.33 to 0.51 for the upper limit. These findings indicate that the penile length should be assessed after 24 hours of age by the reference standard of the same ethnicity for identifying micropenis and that buried penis is not uncommon in Japanese full-term newborns.

  12. Mapping exposed and buried drainage systems using remote sensing in the Negev Desert, Israel

    Science.gov (United States)

    Blumberg, Dan G.; Neta, Tali; Margalit, Nir; Lazar, Michael; Freilikher, Valentin

    2004-08-01

    This paper examines the use of optical visible and infrared (IR) data, Synthetic Aperture Radar data (SAR), and Ground Penetrating Radar (GPR) for detection, identification and mapping of exposed and buried channels under sands in the western Negev, Israel and northern Sinai, Egypt. Field observations and shallow geophysical methods corroborated the observations. The Halutza, Agur and Shunra sand dunes are the continuation of the northern Sinai dunes. Playa-type sediments from the late Quaternary are found in upper reaches of dry river channels between the dunes of the Northwest Negev and represent a deterioration of the drainage system, caused by shifting sand dunes. A dual-polarimetric radar SIR-C image from SRL-1, having two frequencies and two polarizations, exhibits meaningful differences in reflectance between the buried and abandoned channels and their surroundings. The buried continuation of Wadi Mobra and the larger Nahal Nizzana channels, under the western Shunra sand dunes, can be observed in L-band radar data. These channels are not clearly observed either in the Landsat thematic mapper TM Visible, nor in the near-infrared (NIR) images. The radar wavelengths and polarizations that improve the contrast between the buried river beds and the surrounding sand mantle are (in descending order): L(HV), L(HH) and C(HH). However, in places where the sand mantle is very thick, or where channels cut through bedrock, the visible and near infrared data (from Landsat TM) are easier to interpret, and tend to be more useful for mapping fluvial patterns.

  13. A servo controlled gradient loading triaxial model test system for deep-buried cavern

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xu-guang [College of Engineering, Ocean University of China, Qingdao 266100 (China); Shandong Provincial Key Laboratory of Ocean Engineering, Qingdao 266100 (China); Research Center of Geotechnical and Structural Engineering, Shandong University, Jinan 250061 (China); Zhang, Qiang-yong; Li, Shu-cai [Research Center of Geotechnical and Structural Engineering, Shandong University, Jinan 250061 (China)

    2015-10-15

    A servo controlled gradient loading model test system is developed to simulate the gradient geostress in deep-buried cavern. This system consists of the gradient loading apparatus, the digital servo control device, and the measurement system. Among them, the gradient loading apparatus is the main component which is used for exerting load onto the model. This loading apparatus is placed inside the counterforce wall/beam and is divided to several different loading zones, with each loading zone independently controlled. This design enables the gradient loading. Hence, the “real” geostress field surrounding the deep-buried cavern can be simulated. The loading or unloading process can be controlled by the human-computer interaction machines, i.e., the digital servo control system. It realizes the automation and visualization of model loading/unloading. In addition, this digital servo could control and regulate hydraulic loading instantaneously, which stabilizes the geostress onto the model over a long term. During the loading procedure, the collision between two adjacent loading platens is also eliminated by developing a guide frame. This collision phenomenon is induced by the volume shrinkage of the model when compressed in true 3D state. In addition, several accurate measurements, including the optical and grating-based method, are adopted to monitor the small deformation of the model. Hence, the distortion of the model could be accurately measured. In order to validate the performance of this innovative model test system, a 3D geomechanical test was conducted on a simulated deep-buried underground reservoir. The result shows that the radial convergence increases rapidly with the release of the stress in the reservoir. Moreover, the deformation increases with the increase of the gas production rate. This observation is consistence with field observation in petroleum engineering. The system is therefore capable of testing deep-buried engineering structures.

  14. Assessment of incineration and melting treatment technologies for RWMC buried waste

    Energy Technology Data Exchange (ETDEWEB)

    Geimer, R.; Hertzler, T.; Gillins, R. (Science Applications International Corp., Idaho Falls, ID (United States)); Anderson, G.L. (EG and G Idaho, Inc., Idaho Falls, ID (United States))

    1992-02-01

    This report provides an identification, description, and ranking evaluation of the available thermal treatment technologies potentially capable of treating the Idaho National Engineering Laboratory Radioactive Waste Management Complex (RWMC) buried mixed waste. The ranking evaluation focused separately upon incinerators for treatment of combustible wastes and melters for noncombustible wastes. The highest rank incinerators are rotary kilns and controlled air furnaces, while the highest rank melters are the hearth configuration plasma torch, graphite electrode arc, and joule-heated melters. 4 refs.

  15. Electromagnetic diffraction by an impedance cylinder buried halfway between two half-spaces

    KAUST Repository

    Salem, Mohamed

    2011-08-01

    We consider the problem of electromagnetic diffraction from a cylinder with impedance surface and half-buried between two dielectric media. An arbitrary located electric dipole provides the excitation. The harmonic solution is presented as a series sum over a spectrum of a discrete-index Hankel transform, and the spectral amplitudes are determined by solving an infinite linear system of equations, which is constructed by applying the orthogonality relation of the 1D Green\\'s function. © 2011 IEEE.

  16. A servo controlled gradient loading triaxial model test system for deep-buried cavern

    International Nuclear Information System (INIS)

    A servo controlled gradient loading model test system is developed to simulate the gradient geostress in deep-buried cavern. This system consists of the gradient loading apparatus, the digital servo control device, and the measurement system. Among them, the gradient loading apparatus is the main component which is used for exerting load onto the model. This loading apparatus is placed inside the counterforce wall/beam and is divided to several different loading zones, with each loading zone independently controlled. This design enables the gradient loading. Hence, the “real” geostress field surrounding the deep-buried cavern can be simulated. The loading or unloading process can be controlled by the human-computer interaction machines, i.e., the digital servo control system. It realizes the automation and visualization of model loading/unloading. In addition, this digital servo could control and regulate hydraulic loading instantaneously, which stabilizes the geostress onto the model over a long term. During the loading procedure, the collision between two adjacent loading platens is also eliminated by developing a guide frame. This collision phenomenon is induced by the volume shrinkage of the model when compressed in true 3D state. In addition, several accurate measurements, including the optical and grating-based method, are adopted to monitor the small deformation of the model. Hence, the distortion of the model could be accurately measured. In order to validate the performance of this innovative model test system, a 3D geomechanical test was conducted on a simulated deep-buried underground reservoir. The result shows that the radial convergence increases rapidly with the release of the stress in the reservoir. Moreover, the deformation increases with the increase of the gas production rate. This observation is consistence with field observation in petroleum engineering. The system is therefore capable of testing deep-buried engineering structures

  17. Multicomponent Seismo-acoustic Surface Waves Beamforming For Undersea Buried Object Detection

    OpenAIRE

    Kotenkoff, Cyril; Lacoume, Jean-Louis; Mars, Jerome,

    2005-01-01

    A beamforming method adapted to Stoneley-Scholte waves is presented, in the context of buried objects detection in the seabed. All the waves particularities are exploited in a wideband multicomponent array processing: velocity, dispersion and polarization. These propagation features must be estimated. The incident wave is used for this purpose. Then a signal model is de_ned according to Stoneley-Scholte wave's propagation, in order to derived optimal and suboptimal receptors. The localization...

  18. Mapping Buried Impact Craters in the Chryse Basin to Understand the Distribution of Outflow Channel Sediment

    Science.gov (United States)

    Miller, Moira; Frey, Herbert V.

    2016-01-01

    The Chryse Basin's location in the northern hemisphere of Mars allowed it to collect water from a number of major outflow channels. These outflows likely deposited significant amounts of sediment within the Basin. This project's goal was to see if mapping buried impact craters, revealed as Quasi-Circular Depressions (QCDs) in Mars Orbiter Laser Altimeter (MOLA) data, could be used to determine the distribution and variation of sediment thickness within the Basin. QCDs, including likely buried impact craters, were mapped to test the hypothesis that further into the basin there would be fewer smaller craters because thicker sediments would have preferentially covered them. Mapping was done using Gridview, an interactive graphics program that manipulates data, in this case topographic data from MOLA. It should be possible to estimate the thickness of the sediment from the smallest buried craters found in a given area, and therefore map out the change in sediment thickness across the basin. The smallest QCDs beginning to be completely covered by sediment were just below 30 km in diameter. The minimum sediment needed to cover a QCD of this size was calculated to be between 1-2km. Therefore, the absence of QCDs below 30 km in the NE corner of Chryse could be explained by sediment at least that thick. Lower thickness is expected elsewhere in the basin, especially in the SW, where more QCDs with smaller diameters were found. The method of mapping buried impact craters provides a way to determine variations in sediment thickness within the Chryse Basin. This method could be used on other sediment-covered areas to learn about past water flow.

  19. Discovery, mapping and interpretation of buried cultural resources non-invasively with ground-penetrating radar

    Science.gov (United States)

    Conyers, Lawrence B.

    2011-09-01

    Ground-penetrating radar is an extremely useful tool for the mapping and interpretation of buried cultural remains within 2-3 metres of the surface, especially when the stratigraphy is complex. Standard reflection profiles can be processed to correct for depth and distance, and also filtered and processed to make cultural features visible. When many profiles are collected in closely spaced transects in a grid, reflections can be re-sampled and displayed in amplitude slice-maps, and isosurface renderings to make buried features visible. Sometimes, however, the abundance and complexity of subsurface reflections is so complex that each individual profile must be interpreted manually, which necessitates an understanding of radar wave propagation, reflection, refraction and attenuation in the ground. In order to differentiate reflections from cultural features this understanding of radar energy must be merged with an understanding of the chemistry of the ground, soil and geological stratigraphy, and how those variables affect radar reflections. When taken as a package of visualization tools, GPR can be used as an effective tool for interpreting aspects of history and culture at buried sites in ways not possible using traditional archaeological methods.

  20. Detection of Microbial sulfate-reduction associated with buried stainless steel coupons

    International Nuclear Information System (INIS)

    The objective of this study was to demonstrate applicability of an innovative radioactive isotope method for imaging microbial activity in geological materials to a comprehensive study of metal corrosion. The method was tested on a sample of stainless steel coupons that had been buried as part of a corrosion study initiated by the National Institute of Standards and Testing or NIST (known as National Bureau of Standards prior to 1988) in 1970. The images showed evidence of microbial activity that could be mapped on a millimeter scale to coupon surfaces. A second more conventional isotope tracer method was also used to provide a quantitative measure of the same type of microbial activity in soil proximal to the buried coupons. Together the techniques offer a method for evaluating low metabolic levels of activity that have the potential for significant cumulative corrosion effects. The methods are powerful tools for evaluation of potential for microbial induced corrosion to buried steel components used on pipelines, in the power and communications infrastructure, and in nuclear waste repository containers

  1. COMBINATION OF VENLAFAXINE AND DIAZEPAM ATTENUATES MARBLE-BURYING BEHAVIOR OF MICE

    Directory of Open Access Journals (Sweden)

    Parle Milind

    2011-03-01

    Full Text Available Obsessive-Compulsive Disorder (OCD is an anxiety disorder featuring intrusive and troubling symptoms, which are perceived as the products of one’s own mind. This disorder is characterized by absurd, recurrent and persistent thoughts (obsessions followed by certain stereotyped actions (compulsions. The OCD patients realize the irrational nature of thoughts and rituals, but feel helpless and hopeless about controlling them. Numerous genes modulating the serotonin and dopaminergic systems are thought to participate in the pathophysiology of OCD. Marble-burying behavior of mice has been employed to study anxiety disorders including obsessive–compulsive disorder (OCD. The aim of this study was to test the efficacy of venlafaxine and diazepam per se and in combination on marble-burying behavior of mice. In the present project a total of 126 male Swiss mice divided in 21 groups were employed. Venlafaxine (1 mg kg-1i.p. per se as well as diazepam (0.25 mg kg-1i.p. per se did not show any anti-compulsive activity. But, the combination comprising of ineffective doses of venlafaxine (1 mg kg-1i.p. and diazepam (0.25 mg kg-1i.p. showed significant anti-compulsive activity as reflected by inhibition of marble-burying behavior.

  2. Buried stone lines in deserts - What can they tell us about landscape evolution?

    Science.gov (United States)

    Dietze, M.; Kleber, A.

    2009-04-01

    Stone pavements are typical features of climate-sensitive arid environments. They allow formation of cumulic soils, protected from erosion, which may be used as archives that recorded past geomorphologic and pedologic processes. Stone lines within the soil column resulted from buried stone pavements. These stone lines, situated between compound soil horizons were affected by postdepositional processes that may be attributed to specific palaeoenvironmental conditions. From Cima Volcanic Field, eastern Mojave Desert, California, we present detailed alignment measurements of buried stone stratae. Soils in the study area were developed on basalt flows of middle Pleistocene age and consist mainly of aeolian dust which was overprinted by several phases of soil formation and stone pavement development. Stones that were arranged in specific depth intervals between compound soil horizons showed prominent orientation patterns that may be attributed to geomorphic processes that created, distorted or reworked at least two ancient stone pavements, now covered by sediment and the modern pavement. We suggest fluvial (re-)orientation of surficial stones prior to burial. Furthermore, a lateral displacement of clasts within the sediment matrix is recorded. The stratigraphic position of realigned stone lines within soil horizons presumably formed, both, under humid and arid environmental conditions allows the description of geomorphic processes for discrete climatic frameworks. Buried stone pavements are thus a unique opportunity for investigating past landscape dynamics, not recorded in other archives.

  3. Acoustic and Doppler radar detection of buried land mines using high-pressure water jets

    Science.gov (United States)

    Denier, Robert; Herrick, Thomas J.; Mitchell, O. Robert; Summers, David A.; Saylor, Daniel R.

    1999-08-01

    The goal of the waterjet-based mine location and identification project is to find a way to use waterjets to locate and differentiate buried objects. When a buried object is struck with a high-pressure waterjets, the impact will cause characteristic vibrations in the object depending on the object's shape and composition. These vibrations will be transferred to the ground and then to the water stream that is hitting the object. Some of these vibrations will also be transferred to the air via the narrow channel the waterjet cuts in the ground. Currently the ground vibrations are detected with Doppler radar and video camera sensing, while the air vibrations are detected with a directional microphone. Data is collected via a Labview based data acquisition system. This data is then manipulated in Labview to produce the associated power spectrums. These power spectra are fed through various signal processing and recognition routines to determine the probability of there being an object present under the current test location and what that object is likely to be. Our current test area consists of a large X-Y positioning system placed over approximately a five-foot circular test area. The positioning system moves both the waterjet and the sensor package to the test location specified by the Labview control software. Currently we are able to locate buried land mine models at a distance of approximately three inches with a high degree of accuracy.

  4. Modelling of coupled heat and moisture flows around a buried electrical cable

    Directory of Open Access Journals (Sweden)

    Eslami Hossein

    2016-01-01

    Full Text Available The admissible current within a buried electrical power cable is limited by the maximum allowed temperature of the cable (Joule effect. The thermal properties of the surrounding soil controls heat dissipation around the cable. The main focus of the study was to evaluate the coupled heat and moisture flow around such buried electrical cables. The heat dissipation of a buried power cable was simulated in the surrounding soil at unsteady conditions. The hydro-thermal coupling was modelled by taking into account the moisture flow of liquid water and vapour, and the heat flow in the soil by convection and advection. As the thermal vapour diffusion enhancement factor (η appears to be a key parameter, the sensitivity study of the coupled heat and moisture flow in the ground regarding this parameter was performed. The variations of the degree of saturation and the temperature of the surrounding soil were studied over 180 days of heating. The results showed that the moisture flow was mainly caused by the vapour transport under temperature gradients. These results emphasized the significant effect of the hydrothermal characteristics of surrounding soil. The radius of influence of the power cable was also evaluated.

  5. Scalability of buried microreflector light-emitting diodes for high-current applications

    Science.gov (United States)

    Illek, Stefan; Pietzonka, Ines; Ploessl, Andreas; Stauss, Peter; Wegleiter, Walter; Windisch, Reiner; Wirth, Ralph; Zull, Heribert; Streubel, Klaus P.

    2003-07-01

    The combination of wafer soldering using metal layers and the introduction of buried micro-reflector structures has proven to be a promising approach to fabricate high brightness, substrate-less LEDs in the AlGaInP material system. In addition to the enhanced light output, the scalability of this approach has been predicted as a major advantage. In contrast to other approaches, larger area LEDs can be fabricated without altering the epitaxial structure and thickness of layers simply by offering a larger area for light generation. First samples of amber (λ = 615 nm) buried micro-reflector LEDs with side-length up to 1000 μm have been realized. Devices mounted in packages with improved heat sinks are capable of low voltage CW operation with currents as high as 600 mA (Vfwlumen. Already these first experiments demonstrate the potential of the concept of buried micro-reflector LEDs not only for high-brightness but also for high-current operation. The results are among the best values of high-flux LEDs in this wavelength range.

  6. Detection of buried targets using a new enhanced very early time electromagnetic (VETEM) prototype system

    Science.gov (United States)

    Cui, T.J.; Chew, W.C.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.

    2001-01-01

    In this paper, numerical simulations of a new enhanced very early time electromagnetic (VETEM) prototype system are presented, where a horizontal transmitting loop and two horizontal receiving loops are used to detect buried targets, in which three loops share the same axis and the transmitter is located at the center of receivers. In the new VETEM system, the difference of signals from two receivers is taken to eliminate strong direct-signals from the transmitter and background clutter and furthermore to obtain a better SNR for buried targets. Because strong coupling exists between the transmitter and receivers, accurate analysis of the three-loop antenna system is required, for which a loop-tree basis function method has been utilized to overcome the low-frequency breakdown problem. In the analysis of scattering problem from buried targets, a conjugate gradient (CG) method with fast Fourier transform (FFT) is applied to solve the electric field integral equation. However, the convergence of such CG-FFT algorithm is extremely slow at very low frequencies. In order to increase the convergence rate, a frequency-hopping approach has been used. Finally, the primary, coupling, reflected, and scattered magnetic fields are evaluated at receiving loops to calculate the output electric current. Numerous simulation results are given to interpret the new VETEM system. Comparing with other single-transmitter-receiver systems, the new VETEM has better SNR and ability to reduce the clutter.

  7. Site Assessment of Multiple-Sensor Approaches for Buried Utility Detection

    Directory of Open Access Journals (Sweden)

    Alexander C. D. Royal

    2011-01-01

    Full Text Available The successful operation of buried infrastructure within urban environments is fundamental to the conservation of modern living standards. Open-cut methods are predominantly used, in preference to trenchless technology, to effect a repair, replace or install a new section of the network. This is, in part, due to the inability to determine the position of all utilities below the carriageway, making open-cut methods desirable in terms of dealing with uncertainty since the buried infrastructure is progressively exposed during excavation. However, open-cut methods damage the carriageway and disrupt society's functions. This paper describes the progress of a research project that aims to develop a multi-sensor geophysical platform that can improve the probability of complete detection of the infrastructure buried beneath the carriageway. The multi-sensor platform is being developed in conjunction with a knowledge-based system that aims to provide information on how the properties of the ground might affect the sensing technologies being deployed. The fusion of data sources (sensor data and utilities record data is also being researched to maximize the probability of location. This paper describes the outcome of the initial phase of testing along with the development of the knowledge-based system and the fusing of data to produce utility maps.

  8. Microbial communities of buried soils of the Tsaritsyn Defense Line (1718-1720)

    Science.gov (United States)

    Demkina, T. S.; Khomutova, T. E.; Kuznetsova, T. V.; Kontoboitseva, A. A.; Borisov, A. V.

    2016-01-01

    Microbial communities of recent surface soils and the soils buried beneath the rampart of the Tsaritsyn Defense Line (1718-1720) in the Little Ice Age were studied. The contribution of the time factor to the variability in the number of microorganisms from different trophic groups was shown to be minor (0.2-0.3%), although significant. In the upper horizon of the paleosols reflecting the environmental conditions intrinsic to the period of the rampart construction, the lower (by two times) content of live microbial biomass, the lower metabolic activity of the microbial community, and the more contrasting changes in the microbiological parameters as compared to these characteristics in the recent soils were found for all the elements of the local topography. The stabilities of the microbial communities in the buried and recent soils were almost the same. The ecological-trophic structure of the microbial communities in the buried soils evidences that, the climate of the 18th century in the southern Privolzhskaya Upland was more humid than now. At the same time, temperature conditions of the Little Ice Age did not prevent the development of steppe vegetation and corresponding soil microbial communities in this area. Our data on the morphology and physicochemical properties of the soils confirm the assumption about more humid climatic conditions at the beginning of the 18th century in the studied area.

  9. Detection of Microbial sulfate-reduction associated with buried stainless steel coupons

    Energy Technology Data Exchange (ETDEWEB)

    Mark E. Delwiche; M. Kay Adler Flitton; Alicia Olson

    2007-03-01

    The objective of this study was to demonstrate applicability of an innovative radioactive isotope method for imaging microbial activity in geological materials to a comprehensive study of metal corrosion. The method was tested on a sample of stainless steel coupons that had been buried as part of a corrosion study initiated by the National Institute of Standards and Testing or NIST (known as National Bureau of Standards prior to 1988) in 1970. The images showed evidence of microbial activity that could be mapped on a millimeter scale to coupon surfaces. A second more conventional isotope tracer method was also used to provide a quantitative measure of the same type of microbial activity in soil proximal to the buried coupons. Together the techniques offer a method for evaluating low metabolic levels of activity that have the potential for significant cumulative corrosion effects. The methods are powerful tools for evaluation of potential for microbial induced corrosion to buried steel components used on pipelines, in the power and communications infrastructure, and in nuclear waste repository containers.

  10. Bistatic, above-critical angle scattering measurements of fully buried unexploded ordnance (UXO) and clutter.

    Science.gov (United States)

    Waters, Z J; Simpson, H J; Sarkissian, A; Dey, S; Houston, B H; Bucaro, J A; Yoder, T J

    2012-11-01

    Laboratory grade bistatic scattering measurements are conducted in order to examine the acoustic response of realistic fully buried unexploded ordnance (UXO) from above-critical angle insonification, between 2 and 40 kHz. A 127 mm diameter rocket UXO, a 155 mm diameter artillery shell, a natural rock of approximately the same size, and a cinder block are fully buried in water-saturated medium grained sand (mean grain diameter, 240 μm) at depths of 10 cm below the water-sediment interface. A two-dimensional array of bistatic scattering measurements is generated synthetically by scanning a single hydrophone in steps of 3 cm over a 1 m × 1 m patch directly above the targets at a height of 20 cm above the water-sediment interface. Three-dimensional volumetric acoustic images generated from the return waveforms reveal scattering components attributed to geometric and elastic scattering, as well as multiple-scattering interactions of returns between the sediment-water interface and the buried objects. The far-field target strength of the objects is estimated through extrapolation of the angular spectrum. Agreement is found between experimental data and simulated data generated from a finite-element-based, three-dimensional time-harmonic model (2-25 kHz). Separation of the measured UXO from the clutter objects is demonstrated through exploitation of structural-acoustics-based features.

  11. Diagnosing The English Patient: schizoid fantasies of being skinless and of being buried alive.

    Science.gov (United States)

    Doidge, N

    2001-01-01

    The psychological world of The English Patient is explored to deepen the understanding of schizoid states. The protagonist, Almásy, is a remote desert explorer whose triangular sadomasochistic affair with the married Katharine destroys them all. His damaged skin is understood as a symbolic representation of his psychological condition. For the schizoid, love consumes and leads to obliteration of the self, represented by the loss of identifying features, and to traumatic permeability (i.e., the loss of boundaries between self and other, and between the ego and repressed desires). Other schizoid themes are the animation of the inanimate, as in the depiction of the desert as a woman; hidden or buried identities; the digital and destructive experience of emotion represented by the conundrum of the bomb defuser; the sense that everything good is imaginary and might suddenly explode; and the moral unevenness of the characters. Almásy collaborates with the Nazis so he can retrieve Katharine's three-year-old corpse, with which he has necrophilic contact in a cave. Fantasies of the lost object buried within the self, of being buried alive, and of being skinned alive are related to the schizoid condition. Hyperpermeability is proposed as a core schizoid state, underlying schizoid withdrawal.

  12. Comparison of broadband and hyperspectral thermal infrared imaging of buried threat objects

    Science.gov (United States)

    McFee, John E.; Achal, Steve B.; Diaz, Alejandra U.; Faust, Anthony A.

    2013-06-01

    Previous research by many groups has shown that broad-band thermal infrared (TIR) imagers can detect buried explosive threat devices, such as unexploded ordnance (UXO), landmines and improvised explosive devices (IEDs). Broad-band detection measures the apparent temperature - an average over the wave band of the product of the true soil surface temperature and the emissivity. Broad-band detection suffers from inconsistent performance (low signal, high clutter rates), due in part to diurnal variations, environmental and meteorological conditions, and soil surface effects. It has been suggested that hyperspectral TIR imaging might have improved performance since it can, in principle, allow extraction of the wavelength-dependent emissivity and the true soil surface temperature. This would allow the surface disturbance effects to be separated from the soil column (bulk) effects. A significant, and as yet unanswered, question is whether hyperspectral TIR images provide better detection capability (higher probability of detection and/or lower false alarm rate) than do broad-band thermal images. TIR hyperspectral image data of threat objects, buried and surface-laid in bare soil, were obtained in arid, desert-like conditions over full diurnal cycles for several days. Regions of interest containing threat objects and backgrounds were extracted throughout the time period. Simulated broad-band images were derived from the hyperspectral images. The diurnal variation of the images was studied. Hyperspectral was found to provide some advantage over broad-band imaging in detection of buried threat objects for the limited data set studied.

  13. Simulation of the environmental fate and transport of chemical signatures from buried landmines

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-03-01

    The fate and transport of chemical signature molecules that emanate from buried landmines is strongly influenced by physical chemical properties and by environmental conditions of the specific chemical compounds. Published data have been evaluated as the input parameters that are used in the simulation of the fate and transport processes. A one-dimensional model developed for screening agricultural pesticides was modified and used to simulate the appearance of a surface flux above a buried landmine and estimate the subsurface total concentration. The physical chemical properties of TNT cause a majority of the mass released to the soil system to be bound to the solid phase soil particles. The majority of the transport occurs in the liquid phase with diffusion and evaporation driven advection of soil water as the primary mechanisms for the flux to the ground surface. The simulations provided herein should only be used for initial conceptual designs of chemical pre-concentration subsystems or complete detection systems. The physical processes modeled required necessary simplifying assumptions to allow for analytical solutions. Emerging numerical simulation tools will soon be available that should provide more realistic estimates that can be used to predict the success of landmine chemical detection surveys based on knowledge of the chemical and soil properties, and environmental conditions where the mines are buried. Additional measurements of the chemical properties in soils are also needed before a fully predictive approach can be confidently applied.

  14. A computer program to calculate the resistivity and induced polarization response for a three-dimensional body in the presence of buried electrodes

    Science.gov (United States)

    Daniels, Jeffrey J.

    1977-01-01

    Three-dimensional induced polarization and resistivity modeling for buried electrode configurations can be achieved by adapting surface integral techniques for surface electrode configurations to buried electrodes. Modification of. the surface technique is accomplished by considering the additional mathematical terms required to express-the changes in the electrical potential and geometry caused by placing the source and receiver electrodes below the surface. This report presents a listing of a computer program to calculate the resistivity and induced polarization response from a three-dimensional body for buried electrode configurations. The program is designed to calculate the response for the following electrode configurations: (1) hole-to-surface array with a buried bipole source and a surface bipole receiver, (2) hole-to-surface array with a buried pole source and a surface bipole receiver, (3) hole-to-hole array with a buried, fixed pole source and a moving bipole receiver, (4) surface-to-hole array with a fixed pole source on the surface and a moving bipole receiver in the borehole, (5) hole-to-hole array with a buried, fixed bipole source and a buried, moving bipole receiver, (6) hole-to-hole array with a buried, moving bipole source and a buried, moving bipole receiver, and (7) single-hole, buried bipole-bipole array. Input and output examples are given for each of the arrays.

  15. Investigation solution to improve the irradiation reliability of SOI NMOSFET

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A solution is developed to improve the irradiation reliability of SOI NMOSFET(N-type Metal Oxide Semiconductor Field Effect Transistor).This solution,including SOI(Silicon On Insulator)wafer hardening and transistor structure hardening,protects the SOI circuit from total dose irradiation effect.

  16. Characterization of Semiconductor Materials Using AOTF Instruments

    Science.gov (United States)

    Li, G. P.; Cheng, L. J.

    1997-01-01

    A non-invasive characterization of silicon-on-insulator (SOI) wafers using white light interference measured by an AOTF polarimetric hyperspectral imaging instrument will be presented an an illustration of the technology potential. Experiments provided high resolution thickness maps of both silicon and oxide layers with accuracy and observed optically active imperfections and distributions in the structure.

  17. 3D mapping of buried underworld infrastructure using dynamic Bayesian network based multi-sensory image data fusion

    Science.gov (United States)

    Dutta, Ritaban; Cohn, Anthony G.; Muggleton, Jen M.

    2013-05-01

    The successful operation of buried infrastructure within urban environments is fundamental to the conservation of modern living standards. In this paper a novel multi-sensor image fusion framework has been proposed and investigated using dynamic Bayesian network for automatic detection of buried underworld infrastructure. Experimental multi-sensors images were acquired for a known buried plastic water pipe using Vibro-acoustic sensor based location methods and Ground Penetrating Radar imaging system. Computationally intelligent conventional image processing techniques were used to process three types of sensory images. Independently extracted depth and location information from different images regarding the target pipe were fused together using dynamic Bayesian network to predict the maximum probable location and depth of the pipe. The outcome from this study was very encouraging as it was able to detect the target pipe with high accuracy compared with the currently existing pipe survey map. The approach was also applied successfully to produce a best probable 3D buried asset map.

  18. Buried valleys within the Standing Rock Indian Reservation, Sioux County, North Dakota, and Corson County, South Dakota

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This coverage contains information about the buried valleys within the Standing Rock Indian Reservation, Sioux County, North Dakota, and Corson County, South...

  19. Low Altitude Thermal Survey by Means of an Automated Unmanned Aerial Vehicle for the Detection of Archaeological Buried Structures

    OpenAIRE

    Poirier, Nicolas; Hautefeuille, Florent; Calastrenc, Carine

    2013-01-01

    Airborne thermal prospecting is based on the principle that there is a fundamental difference between the thermal characteristics of buried remains and the environment in which they are buried. The French 'Archéodrone' project aims to combine the flexibility and low cost of using an airborne drone with the accuracy of the registration of a thermal digital camera. This combination allows the use of thermal prospection for archaeological detection at low altitude with high-resolution informatio...

  20. Detection of buried pipes by polarimetric borehole radar; Polarimetric borehole radar ni yoru maisetsukan no kenshutsu jikken

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M.; Niitsuma, H. [Tohoku University, Sendai (Japan); Nakauchi, T. [Osaka Gas Co. Ltd., Osaka (Japan)

    1997-05-27

    If the borehole radar is utilized for detection of buried pipes, the underground radar measurement becomes possible even in the situation where the mesurement on the earth surface is difficult, for example, such a place as under the road where there is much traffic. However, since buried pipes are horizontally installed and the existing borehole radar can send/receive only vertical polarization, the measurement conducted comes to be poor in efficiency from a viewpoint of the polarization utilization. Therefore, by introducing the polarimetric borehole radar to the detection of buried pipes, a basic experiment was conducted for the effective detection of horizontal buried pipes. Proposing the use of a slot antenna which can send/receive horizontal polarization in borehole in addition to a dipole antenna which sends/receives vertical polarization, developed was a step frequency type continuous wave radar of a network analyzer basis. As a result of the experiment, it was confirmed that reflection from buried pipes is largely dependent on polarization. Especially, it was found that in the slot dipole cross polarization mesurement, reflection from buried pipes can be emphasized. 4 refs., 5 figs.