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11.
The thermal stability of interfaces between metals (Ni, Pt, Ti, Mo) and III-V compound semiconductors has been investigated
by the application of Rutherford backscattering spectrometry. Metal diffusion and interfacial lattice disorder of the semiconductors
were analyzed for various metal/semiconductor samples annealed at temperatures up to 500°C. The interfaces of Ni/GaAs and
Ti/GaAs were found to be more stable than those of Ni/In-based semiconductors and Ti/ In-based semiconductors, respectively.
Faster diffusion of Pt atoms was ob-served in In-and As-containing materials than in P-containing materials. Mo/ semiconductor
interfaces were the most stable. 相似文献
12.
运用经典电路理论,对MOS功率管的开关特性、驱动原理进行了分析,导出了应用MOS功率管实现高速大电流开关应遵从的原则和方法,并成功地实现了光脉冲上升时间小于5ns、下降时间小于10ns,驱动电流达10~50AP-P激光器电源的要求. 相似文献
13.
介绍采用射线方法检测功率管芯片与基座之间的焊接质量。试验证明,选用合适的透照参数可使X射线照相和X射线实时成像对焊接部位的检测均得到较高的对比灵敏度,但X射线照相法成本低廉,一次可透照多个工件,效率高,为该功率管焊接质量的理想检测方法。 相似文献
14.
M. Nicolaidis 《Journal of Electronic Testing》1991,1(4):257-273
It has been noted by several authors that the classical stuck-at logical fault model might not be an appropriate representation of certain real failures occurring in integrated circuits. Shorts are an important class of such faults. This article gives a detailed analysis of the effects of shorts in self-checking circuits and proposes techniques for dealing with them. More precisely, we show that, unlike other faults such as stuck-at, stuck-on, and stuck-open—which produce only single errors in the place they occur—shorts can produce double errors on the two shorted lines. In particular, feedback shorts can produce double errors on the two shorted lines. The double error is unidirectional for some feedback shorts and non-unidirectional for some others. Furthermore, in some technologies (e.g., CMOS), non-feedback shorts can also produce double non-unidirectional errors. We also show that unlike stuck-at, stuck-on, and stuck-open faults, redundant shorts can destroy the SFS property. Then we propose several techniques for coping with these problems and we illustrate the results by circuit implementation examples.The present study is given for NMOS and CMOS circuits but we show that it is valid for any other technology. 相似文献
15.
16.
绝缘栅双极性晶体管IGBT(insulated gate bipolar transistor)在高电压场合应用时需串联使用满足电压需求。由于器件内部的性能差异和外围电路参数不一致等,引起IGBT模块之间电压不均衡问题,威胁其运行安全。综述了国内外IGBT串联均压方法的发展及其研究现状。根据均压方法机理的不同,将IGBT串联均压方法分为被动均压方法和主动均压方法两种,进一步将主动均压方法归纳为无源控制方法和有源控制方法两类。根据各类方法的基本电路拓扑分析了均压原理,梳理了不同方法在电路拓扑、参数选择和控制策略等方面的优化和最新进展。通过均压效果、附加损耗和可靠性等多方面对不同均压方法进行对比,被动均压方法拓扑简单不需外加控制电路更适合在低频应用场合,在高频应用场合中,准有源栅极控制法以单驱动与无源器件相结合的方式,具有良好的发展前景。最后对IGBT串联均压方法进行了展望。 相似文献
17.
弧焊逆变电源的发展趋势分析 总被引:3,自引:1,他引:3
本文针对弧焊逆变电源中的几个关键问题,如功率开关器件的性能特点,增大输出变压器的功率,逆变电源的智能控制等,评述了当前的技术水平及今后的发展趋势。 相似文献
18.
Gustavo Avolio Dominique M. M.‐P. Schreurs Antonio Raffo Giovanni Crupi Alina Caddemi Giorgio Vannini B. Nauwelaers 《国际射频与微波计算机辅助工程杂志》2014,24(1):109-116
This work presents a straightforward approach aimed at modeling the dynamic I–V characteristics of microwave active solid‐state devices. The drain‐source current generator represents the most significant source of nonlinearity in a transistor and, therefore, its correct modeling is fundamental to predict accurately the current and voltage waveforms under large‐signal operation. The proposed approach relies on using a small set of low‐frequency time‐domain waveform measurements combined with numerical optimization‐based estimation of the nonlinear model parameters. The procedure is applied to a gallium nitride HEMT and silicon FinFET. The effectiveness of the modeling procedure in terms of prediction accuracy and generalization capability is demonstrated by validation of the extracted models under operating conditions different than the ones used for the parameters estimation. Good agreement between measurements and model simulations is achieved for both technologies and in both low‐ and high‐frequency range. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:109–116, 2014. 相似文献
19.
周建林 《上海电力学院学报》2010,(4)
采用顶接触结构分别在SiO2、聚甲基丙烯酸甲酯(PMMA)绝缘层上制备了以并五苯为有源层的两种有机场效应晶体管(OFET),其中SiO2绝缘层采用热生长法制备,PMMA绝缘层采用溶液旋涂法制备。与常规基于无机绝缘层的器件相比,采用聚合物为绝缘层后,不但器件的制作工艺简化和成本降低,而且器件性能大幅提高,经测试,器件的迁移率提到0.153cm2/Vs,而阈值电压降低6V。采用原子力显微镜(AFM)、X射线衍射(XRD)等对器件性能提高的原因进行了详细分析。 相似文献
20.
WANG Haili JI Huifang SUN Shuxiang DING Peng JIN Zhi WEI Zhichao ZHONG Yinghui LI Yuxiao 《西安电子科技大学学报(自然科学版)》2017,44(4):151
InP-based high electron mobility transistors (HEMT) have shown a great potential for national defense and satellite radar in space radiation environment applications. This paper studies the proton radiation damage mechanism of its critical structure InAlAs/InGaAs/InAlAs quantum well. The proton projection range and vacancy defect information are obtained at different incident proton energies of 50keV, 75keV and 200keV by SRIM software. With the increase of proton energy, the proton injection depth is increasing and eventually protons pass through the material layers. Besides, the proton radiation induced vacancy defects numbers around hetero-junction increase first and decrease subsequently, and As vacancies are the main proton radiation induced defects. In addition, non-ionizing energy loss (NIEL) of In0.52Al0.48As and In0.53Ga0.47As material is computed under different incident proton energies by the analytical model. The change trend of NIEL is identical to the induced vacancy numbers, namely, NIEL first increases and then decreases as the incident proton energy increases. Finally the degrading effect of the radiation-induced As defect is detected in the two-dimensional electron gas in the quantum well, which confirms that the major proton radiation damage mechanism of the quantum well is the induced vacancy defects by NIEL. 相似文献