一体化烧结微组装工艺的应用

传统的微组装工艺在军品和民品中广泛应用了三十多年，多种器件微组装难的问题一直是行业内的短板，本文简要介绍了一种新型的微组装工艺，将多种异形基板、多芯片、多元件及多种绝缘子进行整体烧结，替代了传统的微组装工艺，为微组装行业内多种器件组装难的问题指引了方向。     

声表面波器件引线楔形键合跟部微损伤控制研究

声表面波器件内连的主流工艺是硅铝丝超声键合，而跟部微损伤是该工艺最大的质量隐患。该文从超声键合原理和工艺技术出发，对造成跟部微损伤的影响因素进行了分析，并给出了相应的解决方案。该方案使声表面波器件的键合点跟部微损伤得到有效控制。     

温差电器件接触电阻和接触热阻的测试及分析

接触电阻和接触热阻是影响温差电器件性能的两个重要的工艺参数，直接反映器件制造的工艺水平。因此，对器件的接触电阻和接触热阻进行测试分析，将能够定量地了解现行工艺对器件温差电性能的影响程度。本文首先介绍接触电阻的测试方法和实验结果，然后利用所测的数据，再通过对器件输出功率特性的测试，间接地导出器件的接触热阻。据笔者所知，这是温差电器件接触热阻实测数值的首次报道。     

适合VLSI／ULSI的深亚微米MOS器件模型BSIM2的研究

论述了深亚微Ｏ主ＭＯＳ器件模型ＢＳＩＭ２。从强反型区、业阈区、过渡区及输出电阻等几方面，以物理要领为基础进行了较详细分析，并与国内１μｍ工艺的ｎＭＯＳ测量数据进行了比较，得到了满意的结果。     

电热激励硅谐振器件的研究

设计了悬臂梁结构电热激励、压阻拾取硅微机械谐振器件,分析了电热激励和压阻拾取的基本工作原理,设计了与Bipolar工艺兼容的器件制作工艺流程,并制作了器件样品.对真空中器件的幅频特性进行了实验研究,研究结果表明,在粗真空范围内,保持激励功率不变的情况下,微悬臂梁的振幅、谐振频率与真空度之间具有明显的依赖关系,可以用来设计、制作MEMS粗真空谐振式传感器.     

微声学器件封装特性研究

分别采用TO-CAN和SMT形式对微声学器件进行了封装，并对封装后的器件进行了耦合腔测试和指向性测试。测试结果表明，通过减小前入声孔直径大小，能够抑制微音频器件的高频响应；另外通过采用不同的封装结构参数，能够实现∞形和心脏形指向性的微超声器件。     

硅集成器件工艺中的二次缺陷

本文从硅材料质量与器件关系研究入手，对工艺中发现的滑移位错、失配位错、热氧化堆垛层错，以及微缺陷等几种二次缺陷进行了研究，并试图对它们的性质、工艺中的变化、产生原因及消除办法进行归纳，以便对有关工作有所裨益。     

一种基于图像处理的红外微扫描器件测量与校准的方法

在以红外焦平面为核心的红外成像系统中,微扫描器件可以有效提高整个系统的空间分辨率。针对微扫描器件的检测,本文提出了一种基于图像处理的测量与校准方法,并搭建了一套检测系统用于对微扫描器件进行检测与校准。以某型微扫描器件为测试对象,实验结果表明本文所提方法在测量精度、重复精度以及不确定度方面均达到了良好的效果,可以为微扫描器件的设计、生产提供基础支撑。     

微电子器件的抗辐射加固技术

对各类微电子材料的抗辐射特性进行了分析，对Si双极器件和Si CMOS器件、GaAs微波功率器件、新兴光电器件件-VCSEL、LED以及MEMS的抗辐射加固技术进行了探讨，对几种空间单粒子效应（SEE）进行了研究。     

数字信号处理器件发展概况

本文对数字信号处理器件在国内市场上的发展状况进行了介绍，对国内两大主流数字信号处理器件的主要器件的主要结构特点和应用领域进行了分析和比较，对最新信号处理器件的发展动态进行了说明，为ＤＳＰ器件的初不者了解ＤＳＰ概况提供捷径，为选用ＤＳＰ器件进行设计的研究人员提供了一定的理论指导。     

Fabrication and Evaluation of a Thermoelectric Microdevice on a Free-Standing Substrate

Using shadow masks prepared by standard microfabrication processes, we fabricated in-plane thermoelectric microdevices (4 mm × 4 mm) made of bismuth telluride thin films, and evaluated their performance. We used Bi_0.4Te_3.0Sb_1.6 as the p-type semiconductor and Bi_2.0Te_2.7Se_0.3 as the n-type semiconductor. We deposited p- and n-type thermoelectric thin films on a free-standing thin film of Si₃N₄ (4 mm × 4 mm × 4 μm) on a Si wafer, and measured the output voltages of the microdevices while heating at the bottom of the Si substrate. The maximum output voltage of the thermoelectric device was 48 mV at 373 K.     

Fluidic actuation by electrorheological microdevices

Electrorheological microdevices with planar and cylindrical geometry have been developed for control of fluidic microactuators. The devices consist of capacitor elements of 50 μm gap size, which confine a flow channel of 10–20 mm length. A homogeneous electrorheological fluid (ERF) is used for operation of the devices displaying a viscosity change of about 25 for a voltage of 500 V at a pressure difference of 2000 hPa. The maximum control power is 0.65 mW. Switching times are in the order of 50 ms. The microdevices have been used to control the motion of a micropiston with 1 mm stroke fabricated by the LIGA technology.     

Symmetry Analysis of Thermoelectric Energy Converters with Inhomogeneous Legs

Symmetry analysis has been applied to thermoelectric energy converters [thermoelectric generators (TEG), coolers (TEC), and heaters (TEH)] with inhomogeneous legs. The features of the crystallographic symmetry of thermoelectric materials and the symmetry of legs, thermocouples, and modules are studied. The effect of symmetry on the figure of merit Z of thermoelectric energy converters is considered. A general rule for proper placement of legs in thermoelectric converters is developed. A modified tetratomic classification for thermoelectric energy converters with inhomogeneous legs (TEG^a, TEG^b, TEC, and TEH) is proposed. An increase in Z for thermoelectric energy converters with inhomogeneous legs is due to the bulk thermoelectric effect. An increase in Z gives the reduction of irreversible processes in the modules (Joule heating and thermal conductivity), accompanying breaking of the symmetry of the legs. It is found that violations of the symmetry requirements can lead to significant energy losses in converters.     

Module Geometry and Contact Resistance of Thermoelectric Generators Analyzed by Multiphysics Simulation

Thermoelectric device performance is determined by not only the properties of the thermoelectric material but also the geometrical design and thermal matching of the materials. Leg length and contact quality strongly influence thermoelectric generator efficiency. Experimental results for contact properties are compared with the latest performance measurements on modules manufactured from Bi₂Te₃ compounds. Module performance is related to the obtained contact resistance and thermoelectric material properties. The different influences are studied using thermoelectric multiphysics finite-element modeling of examples where, in addition to the thermoelectric field equations, further effects such as convection and radiation as well as the temperature dependency of the material properties are taken into account. Extensive thermoelectric device modeling is used to understand the experimental findings with respect to contact properties and geometry.     

Biomedical microsystems for minimally invasive diagnosis and treatment

Great significant progress has been made in the development of biomedical microdevices in recent years, and these devices are now playing an important role in diagnosis and therapy. This paper presents a review of applications of microelectromechanical systems (MEMS) devices for in vivo diagnosis and therapy, and endoscopic- and catheter-based interventions. MEMS technology has enabled the further development of advanced biomedical microdevices for use in the human body by integration of sensors, actuators, and electronics into small medical devices for use in the body. In this paper, we discuss three categories of such devices: navigation systems, sensors and actuators for catheters and endoscopes, and other minimally invasive techniques. A brief introduction to principles, device structures, packaging, and related issues is presented.     

Preparation of Ring-Shaped Thermoelectric Legs from PbTe Powders for Tubular Thermoelectric Modules

Waste heat recovery—for example, in automotive applications—is a major field for thermoelectric research and future application. Commercially available thermoelectric modules are based on planar structures, whereas tubular modules may have advantages for integration and performance in the field of automotive waste heat recovery. One major drawback of tubular generator designs is the necessity for ring-shaped legs made from thermoelectric material. Cutting these geometries from sintered tablets leads to considerable loss of thermoelectric material and therefore high cost. Direct sintering of ring-shaped legs or tubes of thermoelectric material is a solution to this problem. However, sintering such rings with high homogeneity and density faces some difficulties related to the mechanical properties of typical thermoelectric materials such as lead telluride (PbTe)—particularly brittleness and high coefficient of thermal expansion. This work shows a process for production of thermoelectric rings made of p- and n-doped PbTe. Long tubes of PbTe have been sintered in a current-assisted sintering process with specially designed sintering molds, coated with a diffusion barrier, and finally cut into ring-shaped slices. To demonstrate the technology, a tubular thermoelectric module has been assembled using these PbTe rings.     

无量纲优值对热电制冷系统性能影响分析

建立了无量纲稳态系统热力学模型。并用该模型分析了优值系数对系统性能的影响,优值系数是热电制冷器性能的内在制约,散热和温度条件则是热电制冷性能的外在制约,无量纲优值体现了二者对系统的影响。热电制冷系统的特殊优势再度受到人们关注,但在热电材料优值系数受到限制的现实条件下,热电制冷系统在能效上是难以与压缩式制冷空调系统比较的。     

Detailed Modeling and Irreversible Transfer Process Analysis of a Multi-Element Thermoelectric Generator System

Thermoelectric (TE) power generation technology, due to its several advantages, is becoming a noteworthy research direction. Many researchers conduct their performance analysis and optimization of TE devices and related applications based on the generalized thermoelectric energy balance equations. These generalized TE equations involve the internal irreversibility of Joule heating inside the thermoelectric device and heat leakage through the thermoelectric couple leg. However, it is assumed that the thermoelectric generator (TEG) is thermally isolated from the surroundings except for the heat flows at the cold and hot junctions. Since the thermoelectric generator is a multi-element device in practice, being composed of many fundamental TE couple legs, the effect of heat transfer between the TE couple leg and the ambient environment is not negligible. In this paper, based on basic theories of thermoelectric power generation and thermal science, detailed modeling of a thermoelectric generator taking account of the phenomenon of energy loss from the TE couple leg is reported. The revised generalized thermoelectric energy balance equations considering the effect of heat transfer between the TE couple leg and the ambient environment have been derived. Furthermore, characteristics of a multi-element thermoelectric generator with irreversibility have been investigated on the basis of the new derived TE equations. In the present investigation, second-law-based thermodynamic analysis (exergy analysis) has been applied to the irreversible heat transfer process in particular. It is found that the existence of the irreversible heat convection process causes a large loss of heat exergy in the TEG system, and using thermoelectric generators for low-grade waste heat recovery has promising potential. The results of irreversibility analysis, especially irreversible effects on generator system performance, based on the system model established in detail have guiding significance for the development and application of thermoelectric generators, particularly for the design and optimization of TE modules.     

Nanoscale Organic Thermoelectric Materials: Measurement,Theoretical Models,and Optimization Strategies

The demands for waste heat energy recovery from industrial production, solar energy, and electronic devices have resulted in increasing attention being focused on thermoelectric materials. Over the past two decades, significant progress is achieved in inorganic thermoelectric materials. In addition, with the proliferation of wireless mobile devices, economical, efficient, lightweight, and bio‐friendly organic thermoelectric (OTE) materials have gradually become promising candidates for thermoelectric devices used in room‐temperature environments. With the development of experimental measurement techniques, the manufacturing for nanoscale thermoelectric devices has become possible. A large number of studies have demonstrated the excellent performance of nanoscale thermoelectric devices, and further improvement of their thermoelectric conversion efficiency is expected to have a significant impact on global energy consumption. Here, the development of experimental measurement methods, theoretical models, and performance modulation for nanoscale OTE materials are summarized. Suggestions and prospects for the future development of these devices are also provided.     

Engineering Thermal Conductivity for Balancing Between Reliability and Performance of Bulk Thermoelectric Generators

The nanostructuring approach has significantly contributed to the improving of thermoelectric figure‐of‐merit (ZT) by reducing lattice thermal conductivity. Even though it is an effective method to enhance ZT, the drastically lowered thermal conductivity in some cases can cause thermomechanical issues leading to decreased reliability of thermoelectric generators. Here, an engineering thermal conductivity (κ_eng) is defined as a minimum allowable thermal conductivity of a thermoelectric material in a module, and is evaluated to avoid thermomechanical failure and thermoelectric degradation of a device. Additionally, there is dilemma of determining thermoelectric leg length: a shorter leg is desired for higher W kg^?1, W cm^?3, and W The nanostructuring approach has significantly contributed to the improving of thermoelectric figure‐of‐merit (ZT) by reducing lattice thermal conductivity. Even though it is an effective method to enhance ZT, the drastically lowered thermal conductivity in some cases can cause thermomechanical issues leading to decreased reliability of thermoelectric generators. Here, an engineering thermal conductivity (κ_eng) is defined as a minimum allowable thermal conductivity of a thermoelectric material in a module, and is evaluated to avoid thermomechanical failure and thermoelectric degradation of a device. Additionally, there is dilemma of determining thermoelectric leg length: a shorter leg is desired for higher W kg^?1, W cm^?3, and W $^?1, but it raises the thermomechanical vulnerability issue. By considering a balance between the thermoelectric performance and thermomechanical reliability issues, it is discussed how to improve device reliability of thermoelectric generators and the engineering thermal conductivity of thermoelectric materials.