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1.
半导体超薄层材料的研究,依赖于先进的外延生长技术本文着重该领域的MBE,MOCVD,CBE和ALE的发展现状及关键技术作一综述。  相似文献   

2.
周增圻  潘钟 《半导体学报》1996,17(8):589-594
在MBE生长“DBR型结构性材料”的过程中,由于生长中的多层结构干涉效应,使高温黑体辐射谱呈现振荡现象,利用此现象辅以计算机数据拟合,可以实现MBE生长中层次、组分和厚度的实时监控,对MEBE系统生长垂直腔型结构材料的实时质量监控有重要意义,我们首次在国内采用这项技术,利用红外高温仪对VCSEL器件生长全过程(包括谐振腔)及多种组分DBR的表观衬底热辐射振荡进行监测,采用准黑体模型,结合扫描电镜,  相似文献   

3.
用MOCVD在(100)、GSMBE在(100)和(111)BGaAs上生长了GaInP外延层.PL测试表明,(100)衬底上GaInPPL峰的能量比计算的带隙分别小43(GSMBE生长)和104meV(MOCVD生长).用Kurtz等人的模型对MOCVD和GSMBE生长的GaInP中有序度的不同进行了解释.并讨论了衬底晶向对GaInP中有序程度的影响.  相似文献   

4.
CoSi_2超薄外延膜的生长研究   总被引:2,自引:2,他引:0  
用质量分离的离子束外延(MALE-IBE或简作IBE)法在n-Si(111)上生长了CoSi2超薄外延膜.厚度为10~20nm的CoSi2薄膜的结构特性已由AES、RHEED及RBS作了研究.实验结果表明Co的淀积率对CoSi2单晶生长来说是一个关键因素  相似文献   

5.
郑永梅 《半导体学报》1996,17(12):881-885
本文采用Lowdin微扰原理改进计算效率的局域密度泛函(LDF)线性Muffin-tin轨道原子球近似(LMTO-ASA)能带从头计算方法,以平均键能Em作参考能级,计算了以闪锌矿结构氯化硼为衬底外延生长金刚石(C/BN)、以C0.5(BN)0.5合金为衬底外延生长金刚石与闪锌矿结构氯化硼(CIBN)、以金刚石为衬底外延生长闪锌矿结构氯化硼(C\BN)和金刚石与氮化硼以平均晶格常数匹配生长(C-BN)等四种不同情况下,宽禁带半导体异质结C/BN的价带偏移△Ev值,结果分别为1.505、1.494、1.38  相似文献   

6.
LTC台CHANNELBUSY故障的分析和处理天津日电电子通信工业有限公司田建忠TDNWLTMLTE-SSUB×TTESTLINKLCMFREC4LC图1LTC测试原理图LTTILTMLTCLTE-M在NEAX61程控交换机的日常测试和维护工作中,用...  相似文献   

7.
E10BOCB283交换机中SMM栈的简述北京市电话局纪冬一、概述E10BOCB283交换机是法国ALCA-TEL公司1989年研制成功的新产品,它在控制结构上与原E10BOCB181交换机有很大区别,同时在操作与维护系统的硬/软件方面都有很多变动。...  相似文献   

8.
BreezeCOM无线网络产品BreezeCOM公司以生产无线网络产品为主,主要产品为BreezeNET系列无线以太网和BreezeLINK系列高速无线调制解调器。BreezeCOM产品的优异性能:1.BreezeNET系列是“即插即用”型无线以太网...  相似文献   

9.
消除E10交换机SMM站故障文件超量告警的方法天津市市内电话局申路在ALCATEL1000E10型OCB283交换机中,SMM站常出现“MAXTHERESHOLD-OFA”告警,由于SMM站是OCB283交换机的核心,所以我们对其出现的告警十分重视,...  相似文献   

10.
自对准外延CoSi_2源漏接触CMOS器件技术   总被引:1,自引:0,他引:1  
CO/Ti/Si或TiN/Co/Ti/Si多层薄膜结构通过多步退火技术在Si单晶衬底上外延生长CoSi2薄膜,AES、RBS测试显示CoSi2薄膜具有良好均匀性和单晶性.这种硅化物新技术已用于CMOS器件工艺.采用等离子体增强化学汽相淀积(PECVD)技术淀积氮氧化硅薄膜,并用反应离子刻蚀(RIE)技术形成多晶硅栅边墙.固相外延CoSi2薄膜技术和边墙工艺相结合,经过选择腐蚀,可以分别在源漏区和栅区形成单晶CoSi2和多晶CoSi2薄膜,构成新型自对准硅化物(SALICIDE)器件结构.在N阱CMOS工艺  相似文献   

11.
An important objective of next-generation wireless networks is to provide quality of service (QoS) guarantees. This requires a simple and efficient wireless channel model that can easily translate into connection-level QoS measures such as data rate, delay and delay-violation probability. To achieve this, in Wu and Negi (IEEE Trans. on Wireless Communications 2(4) (2003) 630–643), we developed a link-layer channel model termed effective capacity, for the setting of a single hop, constant-bit-rate arrivals, fluid traffic, and wireless channels with negligible propagation delay. In this paper, we apply the effective capacity technique to deriving QoS measures for more general situations, namely, (1) networks with multiple wireless links, (2) variable-bit-rate sources, (3) packetized traffic, and (4) wireless channels with non-negligible propagation delay. Dapeng Wu received B.E. in Electrical Engineering from Huazhong University of Science and Technology, Wuhan, China, in 1990, M.E. in Electrical Engineering from Beijing University of Posts and Telecommunications, Beijing, China, in 1997, and Ph.D. in Electrical and Computer Engineering from Carnegie Mellon University, Pittsburgh, PA, in 2003. From July 1997 to December 1999, he conducted graduate research at Polytechnic University, Brooklyn, New York. During the summers of 1998, 1999 and 2000, he conducted research at Fujitsu Laboratories of America, Sunnyvale, California, on architectures and traffic management algorithms in the Internet and wireless networks for multimedia applications. Since August 2003, he has been with Electrical and Computer Engineering Department at University of Florida, Gainesville, FL, as an Assistant Professor. His research interests are in the areas of networking, communications, multimedia, signal processing, and information and network security. He received the IEEE Circuits and Systems for Video Technology (CSVT) Transactions Best Paper Award for Year 2001. Currently, he is an Associate Editor for the IEEE Transactions on Vehicular Technology and Associate Editor for International Journal of Ad Hoc and Ubiquitous Computing. He served as Program Chair for IEEE/ACM First International Workshop on Broadband Wireless Services and Applications (BroadWISE 2004); and as TPC member of over 20 conferences such as IEEE INFOCOM'05, IEEE ICC'05, IEEE WCNC'05, and IEEE Globecom'04. He is Vice Chair of Mobile and wireless multimedia Interest Group (MobIG), Technical Committee on Multimedia Communications, IEEE Communications Society. He is a member of the Award Committee, Technical Committee on Multimedia Communications, IEEE Communications Society. He is also Director of Communications, IEEE Gainesville Section. Rohit Negi received the B.Tech. degree in Electrical Engineering from the Indian Institute of Technology, Bombay, India in 1995. He received the M.S. and Ph.D. degrees from Stanford University, CA, USA, in 1996 and 2000 respectively, both in Electrical Engineering. He has received the President of India Gold medal in 1995. Since 2000, he has been with the Electrical and Computer Engineering department at Carnegie Mellon University, Pittsburgh, PA, USA, where he is an Assistant Professor. His research interests include signal processing, coding for communications systems, information theory, networking, cross-layer optimization and sensor networks.  相似文献   

12.
A. Ghafoor presented node-disjoint paths of even networks using Figs. 4, 5, 6,and 7 (Ghafoor, IEEE Trans. Reliability, vol. 38, no. 1, pp. 5-15). However, the paper contains errors which cause confusion. We show that the node-disjoint paths, and Theorem 4 (Ghafoor, IEEE Trans. Reliability, vol. 38, no. 1, pp. 5-15), are not correct. We propose advanced node-disjoint paths, and prove that the fault diameter of even networks is d+1. This is optimal.  相似文献   

13.
Hafnium-based dielectrics are the most promising material for SiO2 replacement in future nodes of CMOS technology. While devices that utilize HfO2 gate dielectrics suffer from lower carrier mobility and degraded reliability, our group has recently reported improved device characteristics with a modified HfxZr1−xO2 [R.I. Hegde, D.H. Triyoso, P.J. Tobin, S. Kalpat, M.E. Ramon, H.-H. Tseng, J.K. Schaeffer, E. Luckowski, W.J. Taylor, C.C. Capasso, D.C. Gilmer, M. Moosa, A. Haggag, M. Raymond, D. Roan, J. Nguyen, L.B. La, E. Hebert, R. Cotton, X.-D. Wang, S. Zollner, R. Gregory, D. Werho, R.S. Rai, L. Fonseca, M. Stoker, C. Tracy, B.W. Chan, Y.H. Chiu, B.E. White, Jr., in: Technical Digest - International Electron Devices Meet, vol. 39, 2005, D.H. Triyoso, R.I. Hegde, J.K. Schaeffer, D. Roan, P.J. Tobin, S.B. Samavedam, B.E. White, Jr., R. Gregory, X.-D. Wang, Appl. Phys. Lett. 88 (2006) 222901]. These results have lead to evaluation of X-ray reflectivity (XRR) for monitoring high-k film thickness and control of Zr addition to HfO2 using measured film density. In addition, a combination of XRR and spectroscopic ellipsometry (SE) is shown to be a fast and non-intrusive method to monitor thickness of interfacial layer between high-k and the Si substrate.  相似文献   

14.
Environmental concerns as well as legal constraints have been pushing research on flip chip technology towards the development of lead-free solders and also to new deposition techniques [Z.S. Karim, R. Schetty, Lead-free bump interconnections for flip-chip applications, in: IEEE/CPMT 1nternational Electronics Manufacturing Technology Symposium, 2000, pp. 274-278, P. Wölflick, K. Feldmann, Lead-free low-cost flip chip process chain: layout, process, reliability, in: IEEE International Electronics Manufacturing Technology (IEMT) Symposium, 2002, pp. 27-34, M. McCormack, S. Jin, The design and properties of new, pb-free solder alloys, in: IEEE/CPMT International Electronics Manufacturing Technology Symposium, 1994, pp. 7-14, T. Laine-Ylijoki, H. Steen, A. Forsten, Development and validation of a lead-free alloy for solder paste applications. IEEE Transactions on Components, Packaging, and Manufacturing technology, 20(3) (1997) 194-198, D. Frear, J. Jang, J. Lin, C. Zhang, Pb-free solders for flip-chip interconnects, JOM, 53(6) (2001) 28-32].Binary and ternary tin alloys are promising candidates to substitute lead-content components. In this paper, we describe an electroplating technique for high density FlipChip packaging [M. Bigas, E. Cabruja, Electrodeposited Sn/Ag for flip chip connection, CDE (2003)]. An analysis using Auger Electron Spectroscopy (AES) together with additional Energy Dispersive Xray analysis (EDS) tests and Scanning Electron Microscope (SEM) analysis have been performed to optimize the reflow process of the electrodeposited bumps.  相似文献   

15.
We describe a finite-element (FE) model for simulating wheel-rolling tissue deformations using a rolling FE model (RFEM). A wheeled probe performing rolling tissue indentation has proven to be a promising approach for compensating for the loss of haptic and tactile feedback experienced during robotic-assisted minimally invasive surgery (H. Liu, D. P. Noonan, B. J. Challacombe, P. Dasgupta, L. D. Seneviratne, and K. Althoefer, "Rolling mechanical imaging for tissue abnormality localization during minimally invasive surgery, " IEEE Trans. Biomed. Eng., vol. 57, no. 2, pp. 404-414, Feb. 2010; K. Sangpradit, H. Liu, L. Seneviratne, and K. Althoefer, "Tissue identification using inverse finite element analysis of rolling indentation," in Proc. IEEE Int. Conf. Robot. Autom. , Kobe, Japan, 2009, pp. 1250-1255; H. Liu, D. Noonan, K. Althoefer, and L. Seneviratne, "The rolling approach for soft tissue modeling and mechanical imaging during robot-assisted minimally invasive surgery," in Proc. IEEE Int. Conf. Robot. Autom., May 2008, pp. 845-850; H. Liu, P. Puangmali, D. Zbyszewski, O. Elhage, P. Dasgupta, J. S. Dai, L. Seneviratne, and K. Althoefer, "An indentation depth-force sensing wheeled probe for abnormality identification during minimally invasive surgery," Proc. Inst. Mech. Eng., H, vol. 224, no. 6, pp. 751-63, 2010; D. Noonan, H. Liu, Y. Zweiri, K. Althoefer, and L. Seneviratne, "A dual-function wheeled probe for tissue viscoelastic property identification during minimally invasive surgery," in Proc. IEEE Int. Conf. Robot. Autom. , 2008, pp. 2629-2634; H. Liu, J. Li, Q. I. Poon, L. D. Seneviratne, and K. Althoefer, "Miniaturized force indentation-depth sensor for tissue abnormality identification," IEEE Int. Conf. Robot. Autom., May 2010, pp. 3654-3659). A sound understanding of wheel-tissue rolling interaction dynamics will facilitate the evaluation of signals from rolling indentation. In this paper, we model the dynamic interactions between a wheeled probe and a soft tissue sample using the ABAQUS FE software package. The aim of this work is to more precisely locate abnormalities within soft tissue organs using RFEM and hence aid surgeons to improve diagnostic ability. The soft tissue is modeled as a nonlinear hyperelastic material with geometrical nonlinearity. The proposed RFEM was validated on a silicone phantom and a porcine kidney sample. The results show that the proposed method can predict the wheel-tissue interaction forces of rolling indentation with good accuracy and can also accurately identify the location and depth of simulated tumors.  相似文献   

16.
In this paper, the performance of selected error-control schemes based on forward error-control (FEC) coding for H.263+ video transmission over an additive white Gaussian noise (AWGN) channel is studied. Joint source and channel coding (JSCC) techniques that employ single-layer and 2-layer H.263+ coding in conjunction with unequal error protection (UEP) to combat channel errors are quantitatively compared. Results indicate that with appropriate joint source and channel coding, tailored to the respective layers, FEC-based error control in combination with 2-layer video coding techniques can lead to more acceptable quality for wireless video delivery in the presence of channel impairments. Yong Pei is currently a tenure-track assistant professor in the Computer Science and Engineering Department, Wright State University, Dayton, OH. Previously he was a visiting assistant professor in the Electrical and Computer Engineering Department, University of Miami, Coral Gables, FL. He received his B.S. degree in electrical power engineering from Tsinghua University, Beijing, in 1996, and M.S. and Ph.D. degrees in electrical engineering from Rensselaer Polytechnic Institute, Troy, NY, in 1999 and 2002, respectively. His research interests include information theory, wireless communication systems and networks, and image/video compression and communications. He is a member of IEEE and ACM. James W. Modestino (S′67- M′73- SM′81- F′87) was born in Boston, MA, on April 27, 1940. He received the B.S. degree from Northeastern University, Boston, MA, in 1962, and the M.S. degree from the University of Pennsylvania, Philadelphia, PA, in 1964, both in electrical engineering. He also received the M.A. and Ph.D. degrees from Princeton University, Princeton, NJ, in 1968 and 1969, respectively. He has held a number of industrial positions, including positions with RCA Communications Systems Division, Camden, NJ; General Electronic Laboratories, Cambridge, MA; AVCO Systems Division, Wilmington, MA; GTE Laboratories, Waltham, MA; and MIT Lincoln Laboratories, Lexington, MA. From 1970 to 1972, he was an Assistant Professor in the Department of Electrical Engineering, Northeastern University. In 1972, he joined Rensselaer Polytechnic Institute, Troy, NY, where until leaving in 2002 he was an Institute Professor in the Electrical, Computer and Systems Engineering Department and Director of the Center for Image Processing Research. He has been responsible for teaching and research in the communication, information and signal processing systems area. His specific research interests include communication in fading dispersive channels; detection, estimation and filtering in impulsive or burst noise environments; digital signal, image and video processing; and multimedia communication systems and networks. In 2002 he joined the Department of Electrical and Computer Engineering at the University of Miami, Coral Gables, FL, as the Victor E. Clarke Endowed Scholar, Professor and Chair. He has held visiting positions with the University of California at San Diego, LaJolla, CA (1981–1982); GE Research and Development Center, Schenectady, NY (1988–1989); and Massachusetts Institute of Technology, Cambridge, MA (1995–1996). Dr. Modestino is a past member of the Board of Governors of the IEEE Information Theory Group. He is a past Associate Editor and Book Review Editor for the IEEE TRANSACTIONS ON INFORMATION THEORY. In 1984, he was co-recipient of the Stephen O. Rice Prize Paper Award from the IEEE Communications Society and in 2000 he was co-recipient of the best paper award at the International Packet Video Conference.  相似文献   

17.
A CMOS Gaussian/Triangular Basis functions computation circuit suitable for analog neural networks is proposed. The circuit can be configured to realize any of the two functions. The circuit can approximate these functions with relative root-mean-square error less than 1%. It is shown that the center, width, and peak amplitude of the dc transfer characteristic can be independently controlled. SPICE simulation results using 0.18 μ m CMOS process model parameters of TSMC18 technology are included. Muhammad Taher Abuelma'Atti was born in Cairo, Egypt, in 1942. He received the B.Sc. degree in Electrical Engineering in 1963 from the University of Cairo, Cairo, Egypt, the Ph.D. degree in 1979 and the Doctor of Science degree in 1999 both from the University of Bradford, Bradford, England. From 1963 to 1967, he worked at the Military Technical College in Cairo as a Teaching Assistant. He was with the Iron and Steel Company in Helwan, Cairo, from 1967 to 1973 as a Senior Electrical Engineer. From 1973 to 1976 he was with the College of Engineering, University of Riyadh, Saudi Arabia, as a Teaching Assistant. From 1980 to 1981, he worked with the Faculty of Engineering, University of Khartoum, Sudan, as an Assistant Professor, and from 1981 to 1982 he was with the College of Engineering, King Saud University, Riyadh, Saudi Arabia, as an Assistant Professor. In 1982 he joined the College of Engineering, University of Bahrain and in 1987 he became an Associate Professor. In 1991 he joined the College of Engineering Sciences, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia, where he became a Full Professor in January 1995. Dr. Abuelma'Atti is the recipient of the 1994/1995 Excellence in Teaching Award and the 1995/1996 and 2000/2001 Excellence in Research Award. Both at King Fahd University of Petroleum and Minerals. Dr. Abuelma'Atti is a contributor to Encyclopedia of RF and Microwave Engineering, Kai Chang, Editor, (New York: John Wiley, 2005), Survey of Instrumentation and Measurement, S.A. Dyer, Editor, (New York: John Wiley, 2001), The Encyclopedia of Electrical and Electronic Engineering, J.G. Webster, Editor, (New York:John Wiley, 1999), and Selected Papers on Analog Fiber-Optic Links, E.I. Ackerman, C.H. Cox III and N.A. Riza, Editors, SPIE Milestone Series, (Washington: SPIE Optical Engineering Press, 1998). His research interests include problems related to analysis and design of nonlinear electronic circuits and systems, analog integrated circuits and active networks design. He is the author or co-author of over 500 journal articles and technical presentations. Abdullah Bakri Shwehneh was born in Aleppo Syria, in 1973. He received the B. Sc. degree in electrical engineering in 1998 from Sumy State University, Sumy, Ukraine. In 2001, he received the Postgraduate Diploma in Automatic Control from Aleppo State University, Aleppo, Syria. In 2001, he joined the “Electronic Brain Company for Computer and Electronics” as an Electronic & Computer Engineer and since 2002, he is with King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia, as a Research Assistant. In June 2005 he obtained his Master of Science Degree in Analog Electronics from KFUPM. At present he is a Ph.D. student at KFUPM. His main interests are in Nonlinear circuits, VLSI Analog Design and Neural Networks hardware implementation.  相似文献   

18.
Siamese tracking is one of the most promising object tracking methods today due to its balance of performance and speed. However, it still performs poorly when faced with some challenges such as low light or extreme weather. This is caused by the inherent limitations of visible images, and a common way to cope with it is to introduce infrared data as an aid to improve the robustness of tracking. However, most of the existing RGBT trackers are variants of MDNet (Hyeonseob Nam and Bohyung Han, Learning multi-domain convolutional neural networks for visual tracking, in: Proceedings of the IEEE conference on computer vision and pattern recognition, 2016, pp. 4293–4302.), which have significant limitations in terms of operational efficiency. On the contrary, the potential of Siamese tracking in the field of RGBT tracking has not been effectively exploited due to the reliance on large-scale training data. To solve this dilemma, in this paper, we propose an end-to-end Siamese RGBT tracking framework that is based on cross-modal feature enhancement and self-attention (SiamFEA). We draw on the idea of migration learning and employ local fine-tuning to reduce the dependence on large-scale RGBT data and verify the feasibility of this approach, and then we propose a reliable fusion approach to efficiently fuse the features of different modalities. Specifically, we first propose a cross-modal feature enhancement module to exploit the complementary properties of dual-modality, followed by capturing non-local attention in channel and spatial dimensions for adaptive weighted fusion, respectively. Our network was trained end-to-end on the LasHeR (Chenglong Li, Wanlin Xue, Yaqing Jia, Zhichen Qu, Bin Luo, Jin Tang, LasHeR: A Large-scale High-diversity Benchmark for RGBT Tracking, CoRR abs/2104.13202, 2021) training set and reached new SOTAs on GTOT (C. Li, H. Cheng, S. Hu, X. Liu, J. Tang, L. Lin, Learning collaborative sparse representation for grayscale-thermal tracking, IEEE Trans. Image Process, 25 (12) (2016) 5743–5756.), RGBT234 (C. Li, X. Liang, Y. Lu, N. Zhao, and J. Tang, “Rgb-t object tracking: Benchmark and baseline,” Pattern Recognition, vol. 96, p. 106977, 2019.), and LasHeR (Chenglong Li, Wanlin Xue, Yaqing Jia, Zhichen Qu, Bin Luo, Jin Tang, LasHeR: A Large-scale High-diversity Benchmark for RGBT Tracking, CoRR abs/2104.13202, 2021) while running in real-time.  相似文献   

19.
Over the last few years, 85 cell phones have been disassembled, ground up, dissolved, and analyzed for elemental content, mainly for information about the metals present in the phones, but also for some metalloids and nonmetals. The following list of 38 elements were detected in some or all of the phones: Be, B, Mg, Al, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Y, Nb, Pd, Ag, In, Sn, Sb, Te, Ba, Ta, W, Pt, Au, Tl, Pb, Bi, Pr, Nd, Sm, Eu, Gd, Tb, Dy, and Er. Cadmium was never detected. This paper discusses the methods used for carrying out the analysis, proposes possible sources in the telephones for the elements of interest, the reasons for the interest in most of the elements, and method repeatability.  相似文献   

20.
说明了ITU-T Y.2065 EHM参考模型与ITU-T Y.2060物联网参考模型的区别。参考ITU-T Y.2065分析了EHM业务及其3种子类业务,即EHMH、EHMR和EHMT,并对EHM业务对物联网基础设施的能力需求进行了简要说明。  相似文献   

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