检索结果-内蒙古大学图书馆

Fabrication of Polycrystalline Si 1−x Ge x Films on Oxide for Thin-Film Transistors

MRS Online Proceedings Library 1994年第1期343卷 679-684页

作者： Julie A. Tsai Andrew J. Tang Rafael Reif Department of Materials Science and Engineering Massachusetts Institute of Technology Cambridge USA Department of Electrical Engineering and Computer Science Microsystems Technology Laboratories Massachusetts Institute of Technology Cambridge USA

Polycrystalline-Si1−xGex films have been formed by various methods on oxide-coated Si substrates at temperatures ≤600°C. Compared to thermal growth, plasma deposition of poly-Si1−xGex promotes smoother films with smaller grains having a 200-dominated texture. Poly-Si1−xGex Alms formed by plasma deposition of amorphous-Si1-xGex followed by a crystallization anneal have an even smoother surface with grain sizes enhanced by an order of magnitude and a weak 111 grain texture. Hydrogen incorporated in amorphous-Si1−xGex evolves completely during crystallization without disrupting the smooth surface morphology. The largest grain sizes (∶1.3μm) are achieved in poly-Si1−xGex films formed by Si+ ion implantation for amorphization with a subsequent recrystallization anneal.

关键词：

来源：评论

学校读者我要写书评

暂无评论

High-frequency AC hot-carrier degradation in CMOS circuits

High-frequency AC hot-carrier degradation in CMOS circuits

引用

International Electron Devices Meeting (IEDM)

作者： Vei-Han Chan T.E. Kopley P. Marcoux J.E. Chung Department of Electrical Engineering and Computer Science Microsystems Technology Laboratories Massachusetts Institute of Technology Cambridge MA USA ICBD Technology Development Center Hewlett Packard Company Palo Alto CA USA

The device degradation due to hot carriers generated under high-frequency circuit operation is studied in detail. Two new degradation phenomena are observed at these high frequencies. First, voltage overshoot, due to internal MOSFET parasitic capacitances, causes enhanced hot-carrier degradation. Second, the quasi-static approximation is found to be invalid at high frequencies. For NMOSFETs, fast voltage transitions are found to induce different degradation dynamics; for PMOSFETs, donor-type interface-state generation and electron detrapping both become significant.< >

关键词： Hot carriers Degradation Circuit testing MOSFETs Voltage Stress MOS devices Frequency CMOS technology Logic testing

来源：评论

学校读者我要写书评

暂无评论

Growth and Characterization of Silicon-Germanium Films on Oxide by VLPCVD/PE-VLPCVD

引用

MRS Online Proceedings Library 1993年第1期317卷 603-608页

作者： Tsai, Julie A. Reif, Rafael Department of Materials Science and Engineering Microsystems Technology Laboratories Massachusetts Institute of Technology Cambridge USA Department of Electrical Engineering and Computer Science Microsystems Technology Laboratories Massachusetts Institute of Technology Cambridge USA

Results of Si1−xGex deposition on oxide-coated Si substrates using a PE-VLPCVD (Plasma-Enhanced Very-Low-Pressure Chemical Vapor Deposition) reactor are presented. Thin layers of poly-Si1−xGex deposited with SiH4 and GeH4 at ≤ 600°C had low C and O levels. Two growth modes were examined at 500°C: plasma-initiated thermal growth (VLPCVD) and full plasma-enhanced deposition (PE-VLPCVD). In both cases, Ge incorporation increases sublinearly with gas ratio, growth rates increase with Ge content, and the transition temperature between polycrystalline and amorphous deposition is lower for Si1−xGex than Si. On the other hand, compared to thermal growth, plasma-enhanced deposition promotes not only higher growth rates but also improved structural properties such as smoother surface morphology, more columnar and oriented grains, and the unique feature of direct deposition onto oxide.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Two-stage hot-carrier degradation and its impact on submicron LDD NMOSFET lifetime prediction

Two-stage hot-carrier degradation and its impact on submicro...

引用

International Electron Devices Meeting (IEDM)

作者： Vei-Han Chan J.E. Chung Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA USA

The device degradation of oxide-spacer LDD NMOS transistors due to hot carriers is studied in detail. It is found that the observed saturation in the degradation time dependence is due to a combination of an increase in the series resistance in the lightly-doped drain region, and a reduction of the carrier mobility in the channel and subdiffusion regions. Because the increase in series resistance eventually saturates, an asymptotic degradation rate coefficient can be used to extract a more accurate and consistent value of LDD NMOS lifetime.< >

关键词： Hot carriers Degradation MOSFET circuits MOS devices Stress Charge pumps Interface states Electrical resistance measurement Voltage measurement Electric resistance

来源：评论

学校读者我要写书评

暂无评论

A relaxation/multipole-accelerated scheme for self-consistent electromechanical analysis of complex 3-D microelectromechanical structures 93

A relaxation/multipole-accelerated scheme for self-consisten...

引用

IEEE International Conference on computer-Aided Design

作者： X. Cai H. Yie P. Osterberg J. Gilbert S. Senturia J. White Department of Electrical Engineering and Computer Science Research Laboratory of Electrical and Microsystems Technology Laboratory Research Laboratory of Electrical and Microsystems Technology Laboratory Cambridge MA USA

ISBN: (纸本)9780818644900

In this paper, two approaches to self-consistent electromechanical analysis of three-dimensional micro-electro-mechanical structures are described. Both approaches combine finite-element mechanical analysis with multipole-accelerated electrostatic analysis, the first using a relaxation algorithm and the second using a surface/Newton generalized conjugate-residual scheme. Examples are given to demonstrate the relative merits of the two approaches.

关键词： Electrostatic analysis Performance analysis Contracts Finite element methods Equations Stress Algorithm design and analysis Microactuators Force control Shape

来源：评论

学校读者我要写书评

暂无评论

The impact of hot-electron degradation on CMOS analog subcircuit performance

The impact of hot-electron degradation on CMOS analog subcir...

引用

Custom Integrated Circuits Conference (CICC)

作者： Vei-Han Chan B.W. Scharf J.E. Chung Department of Electrical Engineering and Computer Science Microsystems Technology Laboratories Massachusetts Institute of Technology Cambridge MA USA Analog Devices Inc.orporated Wilmington MA USA

Experimental data on CMOS analog circuit degradation due to hot-electron effects are presented. Because of circuit design constraints, most MOSFETs used for analog applications are biased in the saturation region with low gate voltage. Under such operating conditions, in addition to interface states, significant numbers of hole traps are also generated inside NMOSFETs. Because acceptor-type interface states are mostly unoccupied in the saturation region, hole traps are found to have a much more significant impact on NMOSFET performance. It is demonstrated that analog subcircuit performance degradation is quite sensitive to the particular circuit design and operating conditions. Circuit performance and reliability tradeoffs are also evaluated.

关键词： Degradation Analog circuits Interface states Voltage Stress MOSFETs CMOS analog integrated circuits Circuit synthesis Circuit optimization Digital circuits

来源：评论

学校读者我要写书评

暂无评论

A microfabricated floating-element shear stress sensor using wafer-bonding technology

引用

Journal of Microelectromechanical Systems 1992年第2期1卷 89-94页

作者： Shajii, Javad Ng, Kay-Yip Schmidt, Martin A. Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA USA

A microfabricated floating-element (120 μm × 140 μm × 5 μm) liquid shear stress sensor has been developed using wafer-bonding technology. The sensor has been designed for high shear stresses (1-100 kPa) and high-pressure environments (up to 6600 psi) and utilizes a piezoresistive transduction scheme. Analytical and finite-element method (FEM) modeling have been performed to predict the sensor response. The sensor has been tested for both its mechanical integrity in high-pressure environments and its output response in the controlled environment of a cone and plate viscometer. The processing steps in the fabrication of the sensor, the analytical and FEM modeling, the experimental procedures, and the results of the experiments are described.

关键词： Piezoelectric transducers

来源：评论

学校读者我要写书评

暂无评论

An Integrated Airgap-Capacitor Pressure Sensor and Digital Readout with Sub-100 Attofarad Resolution

引用

Journal of Microelectromechanical Systems 1992年第3期1卷 121-129页

作者： Kung, Joseph T. Lee, Hae-Sueung Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 United States Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 United States

The fabrication and charaterization of an integrated airgap-capacitor pressure sensor is presented. The capacitor fabrication process uses standard IC processing to create NMOS circuits, and an added polysilicon layer to create poly-to-n 4- capacitors with a 0.6-pm-thick dielectric using deposited oxide. Subsequent processing is used to etch the oxide under the polysilicon from the back of the substrate (formed using bulk etching), to produce deformable, parallel-plate, airgap capacitors on the front-side alongside MOS circuits. Sensor chips are fabricated using 100 x 100 μm, 100 fF airgap capacitors with on-chip circuitry. The sensor chip is a part of a capacitive measurement system that uses a charge-redistribu-tion sense technique to achieve very high capacitance resolution. The pressure sensor chips were characterized versus applied pressure in the 0–240 kPa (0–35 psi) range using optical phase measurement interferometry to measure deflection and shape, and charge-redistribution sense techniques to measure capacitance change. Measurements indicate a sensitivity of 0.93 mV/kPa (6.40 mV/psi) with a deflection of 10 nm/kPa (70 nm/psi) from 0–69 kPa (0–10 psi). Standard deviations indicate a static pressure resolution of 0.54 kPa (0.078 psi), which translates to 30 attofarads at a sampling frequency of 11 kHz. © 1992 IEEE

关键词： MOS capacitors Circuits Sensor phenomena and characterization Fabrication Air gaps Capacitive sensors Semiconductor device measurement MOS devices Dielectrics Sensor systems

来源：评论

学校读者我要写书评

暂无评论

A computer-aided design system for microelectromechanical systems (MEMCAD)

引用

Journal of Microelectromechanical Systems 1992年第1期1卷 3-13页

作者： Senturia, Stephen D. Harris, Robert M. Johnson, Brian P. Kim, Songmin Nabors, Keith Shulman, Matthew A. White, Jacob K. Microsystems Technnlnov Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 United States Power Products Division Systems Technology Division IBM Corp. Endicott. Cambridge NY United States Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology MA 07139 United States Research Laboratory of Electronics Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 United States Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge Redmond. MA. United States Microsoft Corp. WA 98052 United States

The authors describe the MIT Microelectromechanical computer-Aided Design system (MEMCAD), in which selected commercial software packages are linked with specialized database and numerical programs to allow designers to quickly perform both mechanical and electrical analyses of structures either described directly, or derived from the design specification (mask data plus process flow). The system architecture, the various modules, and their present status are described, and present system performance is demonstrated with several examples.

关键词： Electromechanical Devices

来源：评论

学校读者我要写书评

暂无评论

A COMPACT, INEXPENSIVE APPARATUS FOR ONE-SIDED ETCHING IN KOH AND HF

引用

SENSORS AND ACTUATORS A-PHYSICAL 1991年第3期29卷 209-215页

作者： KUNG, JT KARANICOLAS, AN LEE, HS Microsystems Technology Laboratories Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 U.S.A.

Silicon micromachining often requires the selective removal of either surface or bulk layers of material from substrates. Often it is advantageous to protect one side of a substrate while the other side is exposed to the etchant. Sometimes an etch can take as long as 8-10 h at temperatures as high as 80-degrees-C, such as in wet etching of bulk silicon in potassium hydroxide (KOH) solution. Other times, the etch may be at room temperature, and there may be prolonged periods of exposure to concentrated hydrofluoric acid (HF) when removing sacrifical layers of oxide. Both KOH and concentrated HF are effective in etching silicon and silicon dioxide respectively, but there is difficulty in finding suitable materials that mask these etchants for long periods of time. Silicon nitride is a good mask for KOH, but is deposited at a relatively high temperature (800-degrees-C), while concentrated HF tends to delaminate or etch most materials. This makes it difficult to protect layers on silicon wafers after any metal deposition. This paper describes a system designed to wet etch substrates from one side only, protecting the front side to a high degree. The one-sided etching concept is introduced, followed by the design of the apparatus with variations on the basic concept. This is followed by a particular implementation in a KOH etching system. Also described as part of the KOH etching system is a simple and economical method for solution level detection based on the conductance of the solution. This detection system compensates for loss of water in the solution due to evaporation when etching at high temperatures. Finally, an example of the usefulness of the one-sided apparatus is given.

关键词： Etching

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：