Modeling of non-equilibrium transport effects in Fully-Depleted GeOI-MOSFETs

Germanium is investigated as basic semiconductor for advanced CMOS nodes. A mobility model at low fields for Ge devices is developed starting from the CVT model, whose parameters are calibrated by comparison with experiments. TCAD simulations of Fully-Depleted (FD) Germanium-On-Insulator (GeOI) n- and p-MOSFETs are presented using both the drift-diffusion and the energy balance transport models. Effects due to non-equilibrium transport in small devices are estimated by varying the energy-relaxation time of the Ge material and by analyzing the phenomenon of velocity overshoot in the channel. It is found that GeOI MOSFETs furnish robust performance improvements when short device lengths are considered due to the influence of non-local effects.     

Quantum-Confined Stark Effect in Ge/SiGe Quantum Wells on Si

In this paper, we present observations of quantum confinement and quantum-confined Stark effect electroabsorption in Ge quantum wells with SiGe barriers grown on Si substrates. Though Ge is an indirect gap semiconductor, the resulting effects are at least as clear and strong as seen in typical III–V quantum well structures at similar wavelengths. We also designed and fabricated a coplanar high-speed modulator, and demonstrated modulation at 10 GHz and a 3.125-GHz eye diagram for 30-$mu$m-sized modulators.      

半导体冰箱的装配工艺对冰箱制冷性能影响的实验研究

热电冰箱又称“半导体冰箱”,是半导体制冷技术应用在家用电器中的典型产品。影响半导体冰箱制冷性能的因素除了半导体制冷材料、冷热端的散热方式外,还取决于其良好的结构设计和合理的装配工艺。     

半导体针杆的限流特性分析

本文从电流源模型，电压源模型，辨证逻辑和形式逻辑等方面，阐明半导体限流猜想是不正确的。     

利用再生晶圆制作太阳电池之研究

能源问题与人类生活关系密切。太阳电池产业将会是未来的重要能源科技之一。因此,本文主要研究以半导体晶圆为材料,通作制作工艺条件的研究与改进以提升太阳电池的发电效率,并讨论了利用半导体厂的报废晶圆制作太阳电池,这不仅可以节省材料成本,还可使工厂报废晶圆的价值发挥到极致。     

GROWTH OF Ge-DOPED Sb2Te3 THIN FILMS BY METAL-ORGANIC CHEMICAL VAPOR DEPOSITION

ABSTRACT

Thin films based on Ge–Sb–Te are the most popular material for non-volatile phase change memory, because this material is more stable in the over-write than other chalcogenide alloy. We fabricated the Ge-doped Sb₂Te₃ rhombohedral thin films by metal-organic chemical vapor deposition (MOCVD) with bubbler type systems for the nonvolatile PCRAM applications and also expected the effects of ratio of respective precusors pressure. In spite of the different Ge bubbler temperature, all thin films have same crystallinity of Sb₂Te₃ phase, which has c-axis orientation perpendicular to the substrates. Even though ratio of relative Ge vapor pressure (%) increases up to 63%, amount of Ge in the films is only about 0.4%. We concluded that reaction between Sb and Te are dominant than other reaction such as Ge–Te or Ge–Sb in current conditions. Also, to improve the reaction of Ge elements in the chamber, controlling amount of Ge precursors may be needed delicately. These results suggest that Ge–Sb–Te thin films can be deposited by metal organic CVD for phase change memory applications.     

交流变频调速传动装置用新型电力半导体器件

电力半导体器件的发展大大促进了交流变频调速传动装置性能的改善，ＭＯＳ栅结构的现代器件的开发成功，可以用很小的输入功率来控制很大的输出功率，并可大大降低装置的功耗，提高工作频率。具有优良反向恢复特性的整流二极管的开发成功，大大降低了高频工作下的功耗。目前的开关器件都是用硅材料制成，但利用ＳｉＣ等材料制成的电力开关器件具有很优良电气特性，是研制理想器件的关键。     

A novel approach to three-dimensional semiconductor process simulation: Application to thermal oxidation

The paper presents a new approach to three-dimensional semiconductor process simulation that overcomes the problem of moving boundaries and mesh generation. Contrary to using unstructured meshes, the approach makes use of the level set method on fixed Cartesian meshes. A concept of multilayer structure is introduced to capture an arbitrary complex structure. To handle a big geometrical scale ratio in a structure, the concept of adaptive mesh refinement is used. A special in-house finite-difference scheme is designed to approximate the relevant equations near material interfaces. In the bulk of regular nodes the standard finite difference schemes are used. Application of the approach to the modelling of oxidation of some typical types of structures used in semiconductor technology is demonstrated.     

以MOCVD为基础的光电子平台设计与开发

光电子平台是光电子器件研发的基础平台,可用于高效叠层薄膜光伏电池、量子激光器、探测器、传感器等光电子器件的研发及制备。本文从材料生长、器件工艺、测试平台、安全设计4个方面讨论了以MOCVD为基础的光电子平台的总体设计思路,包括了制备平台设计、材料生长仿真模拟分析、工艺优化、过程控制优化、测试分析设备整合优化、高危气体管道改造、尾气回收装置设计的实施方案。平台设计将主要为Ⅲ-Ⅴ族化合物半导体材料生长以及器件制作服务,通过不断设计改进最终建设成为集前沿材料生长研究和新型光电子器件研发的光电子技术科学研究平台。     

A Semiconductor Technology Course

A one-year semiconductor technology course for undergraduate senior electrical engineering students is described. The course consists of one semester of lecture followed by one semester of laboratory. The material covered in the lecture is demonstrated to the students by field trips to local industry and in their laboratory. Highly sophisticated technology such as ion-implantation is demonstrated in field trips and technology such as thermal diffusion is encountered by the student in his laboratory course. "Thus, whenever possible, the student can relate his lecture material to observation. The laboratory consists of a complete processing operation where the student starts with a crystal boule and fabricates a packaged device whose terminal characteristics are measured. He or she thus obtains some feeling for the effects of processing on terminal characteristics. Projects are used in conjunction with the laboratory to improve some of the process steps and to give the student some experience in tackling nonstructured problems which are more closely related to professional activities after graduation.     

量子阱结构对GaInP/Ga(In)As/Ge电池的光谱响应改善

采用MOCVD工艺制备具有应变平衡量子阱结构GaInP/Ga(In)As/Ge三结太阳电池的方法,及量子阱结构对中间电池的光谱响应的改善,从而使GaInP/Ga(In)As/Ge三结太阳电池各子电池电流匹配设计更为合理,揭示了量子阱结构提高GaInP/Ga(In)As/Ge三结级联太阳电池光电转换效率的可能性。     

Undergraduate field applications engineers: a successful experimentin electronic design automation technology transfer

The United States has lost its leadership position in semiconductor manufacturing. It is, however, still dominant in the production of electronic design automation (EDA) software which supports semiconductor integrated circuit design and manufacturing. Research on EDA software is performed primarily in US universities. Early use of such software by the US semiconductor industry should constitute a precompetitive advantage that would help to compensate for the US's tack of competitiveness in manufacturing; however, because of the different natures of universities and industry, a significant technology transfer gap exists between them. Universities produce prototype software as research results, whereas the semiconductor industry would prefer to have robust rather than prototype versions. To bridge the gap, it has been proposed that the EDA industry be emulated and undergraduate engineering students used as field applications engineers (UFAEs). This paper describes a reasonably successful first attempt at this approach to EDA software technology transfer and discusses as well what could be done in the future to improve upon it     

Engineering strained silicon-looking back and into the future

The purpose of this article is to explain the basics behind straining and report on the current process technologies available to strain CMOS devices. Strained Si enhances the performance of CMOS devices by increasing carrier mobility without having to make them smaller. As the benefits to be gained from scaling transistors continue to decrease, the commercial interest in using strained Si for CMOS devices has spiked. Additionally, strained Si still retains its integratability in CMOS manufacturing processes, unlike any other semiconductor material. Thus the real test for engineers lies in the ability to cost-effectively develop and apply strained Si technology into current CMOS process. Thus new methods for straining Si is integrated into IC manufacturing as industry interest in this technology continues to grow and also increases the speed, performance and functions of the circuits.     

半导体照明工程的现状与发展趋势

半导体照明具有节能、环保、寿命长、尺寸小等优点,能够应用在各种各样的彩色和白色照明领域.发展半导体照明产业具有重大意义,能缓解能源危机,改善环境污染问题,有利于国民经济可持续发展.本文在介绍半导体照明特点的基础上,论述了国内外半导体照明研究进展和产业化应用情况,分析了我国半导体照明产业发展面临的相关技术问题,最后对半导体照明工程发展趋势作了展望.     

“云智慧仪器”结合“互联网+”和“工业4.0”、CPS的发展趋势，是面向“中国制造2025”的典型代表

本文讨论了“互联网+”、“工业4.0”、CPS、“中国制造2025”和“云智慧科技”的情况,介绍了中国DASP云 智慧仪器的构架和应用实例。并利用INV3062C云智慧仪器进行对比测试,得到了超过十进制12位的测试精度,特别是在 超低频方面有所突破,达到小数点后9位的精度,值得应用推广。     

Development of electronic device simulations for educational purposes

A comprehensive set of semiconductor device simulation tools, written in Java, is being developed for instructional use. These interactive programs can be launched from an electronic textbook or from lecture presentation material. At present these tools demonstrate introductory quantum mechanics, several aspects of semiconductor physics, and both zero-current and drift-diffusion device simulations in one dimension. Development of two-dimensional simulations is in progress.     

基于GaN FETs的高频半桥谐振变换器分析与设计

随着Si材料半导体器件性能逐步达到瓶颈,宽禁带半导体器件(GaN、SiC)在诸多方面展现出了很好的性能,如低导通阻抗,小输入、输出电容等,这些特性使得GaN和SiC器件能够应用在更高的开关频率条件,从而提高系统的功率密度。针对基于GaN FETs构成的高频半桥谐振变换器进行设计,分析了高频条件下寄生电感参数对系统驱动电压及漏源极电压的影响,同时分析了高频条件下系统电压电流测量所需注意的事项及影响因素,为高频条件下GaN FETs的应用提供一定的帮助。     

News from Japan

Construction of a versatile ion accelerator with a reduced cost has become possible by using compressed dry air as an insulating gas. The price of the developed accelerator is about half the cost of current accelerators. It can be used as an ion implantation apparatus for material analyses such as Rutherford back-scattering spectrometry (RBS) and accelerator mass spectrometry (AMS) as well as for manufacturing optical and semiconductor devices     

Ferroelectric polymer Langmuir-Blodgett films for nonvolatile memory applications

We review the potential for integrating ferroelectric polymer Langmuir-Blodgett (LB) films with semiconductor technology to produce nonvolatile ferroelectric random-access memory (NV-FRAM or NV-FeRAM) and data-storage devices. The prototype material is a copolymer consisting of 70% vinylidene fluoride (VDF) and 30% trifluoroethylene (TrFE), or P(VDF-TrFE 70:30). Recent work with LB films and more conventional solvent-formed films shows that the VDF copolymers are promising materials for nonvolatile memory applications. The prototype device is the metal-ferroelectric-insulator-semiconductor (MFIS) capacitance memory. Field-effect transistor (FET)-based devices are also discussed. The LB films afford devices with low-voltage operation, but there are two important technical hurdles that must be surmounted. First, an appropriate method must be found to control switching dynamics in the LB copolymer films. Second, the LB technology must be scaled up and incorporated into the semiconductor-manufacturing process, but since there is no precedent for mass production of LB films, it is difficult to project how long this will take.     

Analysis and Control of Harmonic Current in Systems with Static Power Converters

In the last 50 or 60 years, the development of rectifier and semiconductor technology has led to new products and applications for drives in all industries. These semiconductor converters produce harmonics in the ac power system. With the widespread application of these economical power supplies, problems are arising that should be approached from a logical standpoint and preventive measures taken. The theory of the problem and the solution to it is discussed.