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排序方式: 共有893条查询结果,搜索用时 15 毫秒
51.
Yang Peifeng Li Jingchun Yu Qi Wang Xiangzhan Yang Mohua 《电子科学学刊(英文版)》2002,19(1):108-112
Based on theoretical analysis and computer-aided simulation, optimized design prin-ciples for Si/SiGe PMOSFET are given in this paper, which include choice of gate materials, determination of germanium percentage and profile in SiGe channel, optimization of thickness of dioxide and silicon cap layer, and adjustment of threshold voltage.In the light of these principles, a SiGe PMOSFET is designed and fabricated successfully.Measurement indicates that the SiGe PMOSFET‘s(L=2μ同洒45 mS/mm(300K) and 92 mS/mm(77K) ,while that is 33mS/mm (300K) and 39mS/mm (77K) in Si PMOSFET with the same structure. 相似文献
52.
53.
提出了一种集成于电源管理芯片内部的过热保护电路。采用0.6μm BiCMOS工艺参数,对电路进行模拟仿真,并与先前提出的过热保护电路进行比较。结果表明,该电路具有关断和开启阈值点的准确性强、对温度灵敏度高、超低静态电流和低功耗等特点。 相似文献
54.
In this paper, we will present our recent research on the growth and characterization of some Si-based heterostructures for
optical and photonic devices. The heterostructures to be discussed are ZnO nanorods on Si, SiO2, and other substrates such as SiN and sapphire. We will also consider strained Si1−xGex/Si heterostructures for Si optoelectronics. The performance and functionality extension of Si technology for photonic applications
due to the development of such heterostructures will be presented. We will focus on the results of structural and optical
characterization in relation to device properties. The structural characterization includes x-ray diffraction for assessment
of the crystallinity and stress in the films and secondary ion mass spectrometry for chemical analysis. The optical properties
and electronic structure were investigated by using photoluminescence. The device application of these thin film structures
includes detectors, lasers, and light emitting devices. Some of the Si-based heterostructures to be presented include devices
emitting and detecting up to the blue-green and violet wave lengths. 相似文献
55.
Ricardo A. Aroca C. Andre T. Salama 《Analog Integrated Circuits and Signal Processing》2006,48(3):167-174
This paper presents the design and implementation of a new wide dynamic range parallel feedback (PF) transimpedance amplifier
(TIA) for 10 Gb/s optical links. The wide dynamic range is attributed to the novel TIA architecture employing both shunt-shunt
and shunt-series feedback networks. The outstanding features of the TIA are wide dynamic range, high gain, low power consumption
and design simplicity. A prototype implemented in a 0.5 μm SiGe BiCMOS technology and operating at −3.3 V power supply features
an 18.4 dBm dynamic range with a BER less than 10−12, an optical sensitivity of −16 dBm, optical overload of +2.4 dBm, a bandwidth of 8.27 GHz, a gain of 950 Ω and a power consumption
of 189 mW. The new parallel feedback architecture offers improved overload and noise performance when compared to previously
reported, state of the art, single feedback TIA designs and meets all the 10 Gigabit Ethernet and short-reach OC-192 SONET
specifications.
Ricardo Andres Aroca received the B.S. (Hons) degree in electrical engineering from the University of Windsor, Canada, and the M.S. degree from
the University of Toronto, Canada, in 2001 and 2004, respectively. In 2000 he spent two 4 month internships with Nortel Networks
in the Microelectronics Department. Mr. Aroca received the Natural Sciences and Engineering Research Counsel of Canada (NSERC)
Postgraduate Scholarship award in 2002. He is currently working toward the Ph.D. degree at the University of Toronto where
his research interests lie in the area of high-frequency integrated circuits for wireless and wireline communication systems.
C. Andre T. Salama received the B.A.Sc. (Hons.) M.A.Sc. and Ph. D. degrees, all in Electrical Engineering, from the University of British Columbia
in 1961, 1962 and 1966 respectively. From 1962 to 1963 he served as a Research Assistant at the University of California,
Berkeley. From 1966 to 1967 he was employed at Bell Northern Research, Ottawa, as a Member of Scientific Staff working in
the area of integrated circuit design. Since 1967 he has been on the staff of the Department of Electrical and Computer Engineering,
University of Toronto where he held the J.M. Ham Chair in Microelectronics from 1987 to 1997. In 1992, he was appointed to
his present position of University Professor for scholarly achievements and preeminence in the field of microelectronics.
In 1989-90, he was awarded the ITAC/NSERC Research Fellowship in information technology. In 1994, he was awarded the Canada
Council I.W. Killam Memorial Prize in Engineering for outstanding career contributions to the field of microelectronics. In
2000, he received the IEEE Millenium Medal. In 2003, he received the Outstanding Lifetime Achievement Award from the Canadian
Semiconductor Technology Conference for seminal and outstanding contributions to semiconductor device research and promotion
of Canadian University research in microelectronics. In 2004, he received the NSERC Lifetime Achievement Award of Research
Excellence for outstanding and sustained contributions to the field of microelectronics and the Networks of Centres of Excellence
(NCE) Recognition Award for research excellence and outstanding leadership.He was associate editor of the IEEE Transactions
on Circuits and Systems in 1986–88 and a member of the International Electron Devices Meeting (IEDM) Technical Program Committeein
1980–82, 1987–89 and 1996–98. He was the chair of the Solid State Devices Subcommittee for IEDM in 1998 and was a member of
the editorial board of Solid State Electronics from 1984 to 2002. He is presently a member of the editorial board of the Analog
IC and Signal Processing Journal and the Technical Program Committee of the International Symposium on Power Semiconductor
Devices and ICs (ISPSD) and the Technical ProgramCommittee of the International Symposium on Low Power Electronics and Design
(ISLPED). He chaired the technical program committee of ISPSD in 1996 and was the general chair for the conference in 1999.Dr.
Salama is the Scientific Director of Micronet, a network of centres of excellence focussing on microelectronics research and
funded by the Canadian Government and Industry. He has published extensively in technical journals, is the holder of eleven
patents and has served as a consultant to the semiconductor industry in Canada and the U.S. His research interests include
the design and fabrication of semiconductor devices and integrated circuits with emphasis on deep submicron devices as well
as circuits and systems for high speed, low power signal processing applications. Dr. Salama is a Fellow of the Institute
of Electrical and Electronics Engineers, a Fellow of the Royal Society of Canada, a Fellow of the Canadian Academy of Engineering,
a member of the Association of Professional Engineers of Ontario, the Electrochemical Society and the Innovation Management
Association of Canada. 相似文献
56.
对现代的双极型晶体管而言,载流子在基极和集电极的空间电荷区(CB SCR)传输延迟可比基极渡越时间,甚至要大于后者。为了更精确地表征了SiGe HBT的射频噪声性能,对van Vliet模型做了扩展,使其包含基极集电极空间电荷区的延迟效应。用2个与噪声相关的延迟时间对transport模型进行了扩展,使得在没有非准静态Y参数的情况下仍然可以对基极和集电极电流噪声进行精确建模。最后,在JC=12.2 mA/μm2,AE=0.12×18μm2条件下,分别对2种模型的基极和集电极噪声电流谱及其归一化相关系数做图并与计算得出的解析值相比较,验证了模型的有效性。 相似文献
57.
58.
为了提高运算放大器的驱动能力,依据现有CMOS集成电路生产线,介绍一款新型BiCMOS集成运算放大电路设计,探讨BiCMOS工艺的特点。在s_Edit中进行“BiCMOS运放设计”电路设计,并对其电路各个器件参数进行调整,包括M0s器件的宽长比和电客电阻的值。完成电路设计后,在Tspice中进行电路的瞬态仿真,插入CMOS,PNP和NPN的工艺库,对电路所需的电源电压和输入信号幅度和频率进行设定调整,最终在W—Edit输出波形图。在MCNC0.5μm工艺平台上完成由MOs、双极型晶体管和电容构成的运算放大器版图设计。根据设计的版图,设计出BiCMOS相应的工艺流程,并提取各光刻工艺的掩模版。 相似文献
59.
K.H. Shim Y.-H. Kil H.K. Lee M.I. Shin T.S. Jeong S. Kang C.-J. Choi T.S. Kim 《Materials Science in Semiconductor Processing》2011,14(2):128-132
The optical property was studied on the Si0.8Ge0.2/Si strained multiple quantum well (MQW) structure grown using ultra-high vacuum chemical vapor deposition (UHV-CVD). Three peaks are observed in Raman spectrum, which are located at about 510, 410, and 300 cm−1, corresponding to the vibration of Si–Si, Si–Ge, and Ge–Ge phonons, respectively. The photoluminescence (PL) spectrum originates from the radiative recombinations both from the Si substrate and the Si0.8Ge0.2/Si MQW. For Si0.8Ge0.2/Si strained MQW, the transition peaks related to the MQW region observed in the photocurrent (PC) spectrum were preliminarily assigned to electron–heavy hole (e–hh) and electron–light hole (e–lh) fundamental excitonic transitions. 相似文献
60.
This paper describes an analytical model for bulk electron mobility in strained-Si layers as a function of strain.Phonon scattering,columbic scattering and surface roughness scattering are included to analyze the full mobility model.Analytical explicit calculations of all of the parameters to accurately estimate the electron mobility have been made.The results predict an increase in the electron mobility with the application of biaxial strain as also predicted from the basic theory of strain physics of metal oxide semiconductor(MOS) devices.The results have also been compared with numerically reported results and show good agreement. 相似文献