GaAs微波单片集成电路的主要失效模式及机理

从可靠性物理角角度，深入分析了引起砷化镓微波单片机集成电路（GaAs MMIC)退化或失效的主要失效模式及其失效机理，明确了GaAs MMIC的可靠性问题主要表现为有源器件、无源器件和环境因素等引入损伤退化，主要的失效部位是MMIC的有源器件。     

GaAs MESFET可靠性及快速评价新方法的研究

提出了一种快速评价GaAs FET可靠性寿命的新方法.利用GaAs FET失效敏感参数的温度特性和在一定电应力下的退化特性,及温度斜坡法在线快速提取器件失效敏感参数的退化量与温度的关系,从而进一步求出器件的失效激活能等相关的可靠性物理参数.     

电磁脉冲对GaAs LNA损伤及其分析

介绍了电磁脉冲对GaAs低噪声放大器(LNA)损伤机理和损伤模式.利用特定电磁脉冲信号对其进行损伤,通过开帽内部目检、扫描电镜等失效手段和方法,针对该低噪声放大器在电磁脉冲实验中损伤机理及损伤模式进行了分析与讨论.实验表明,GaAs低噪声放大器的可靠性问题主要表现为有源器件、无源器件和环境因素等引入损伤退化,主要失效部位表现为有源器件,指出了对GaAs器件加固的一些措施,对器件设计者和使用者具有一定的参考意义.     

GaAs器件电磁脉冲效应实验与毁伤机理研究

介绍了GaAs低噪声器件电磁脉冲效应实验响应的易损敏感端,对所确定的敏感端注入电磁脉冲方渡,研究了器件在静态时的损伤阈值.根据GaAs器件易损性薄弱环节,从GaAs器件的结构、内部缺陷等出发,探索电磁脉冲对GaAs器件易损性薄弱环节的损毁机理.通过对毁伤实验分析,进一步阐述了电磁脉冲对器件存在潜在不稳定性失效,对器件和整机系统设计者和使用者具有一定的参考意义.GaAs微波低噪声器件在EMP正脉冲注入情况下,获得的损伤阈值约为3.024μJ.在EMP负脉冲注入情况下,损伤阈值约为10.02μJ.初步认为GaAs FET的正脉冲EMP比负脉冲EMP更易损伤.     

GaAs PHEMT器件的失效模式及机理

归纳了GaAs PHEMT器件的几种常见失效模式,并从6个方面分析了PHEMT器件的失效机理:热电子应力退化、氢效应、2DEG结构退化、欧姆接触退化、肖特基接触退化和电迁移.     

GaAs PHEMT器件高温加速寿命试验及物理分析

GaAs微波器件的退化与金属化稳定性密切相关,实现PHEMT器件功能的金属化主要有栅金属化、欧姆接触金属化和信号传输线金属化。本文针对定制的GaAs PHEMT器件的栅金属接触孔链和欧姆接触金属方块条进行了高温加速应力寿命试验,并对器件金属化失效单机理进行寿命预计,同时对试验后的样品进行物理分析。结果显示栅金属接触孔链在180℃下就发生失效,接触孔链表面的金属化层形变,金属化发生了迁移;而AuGeNi欧姆接触在225℃高温下更易发生电迁移失效,金属向体内扩散并在金属条上形成空洞。     

C波段功率GaAs MESFET的可靠性

本文通过功率GaAs MESFET的筛选与环境、寿命试验阐述了器件的早期失效模式模型,估计了可靠性水平,指出了主要失效因素,并用实验方法讨论了突变烧毁失效,分析了失效原因,探讨了提高可靠性的途径。     

GaAs红外发光二极管加速寿命试验研究

本文采用步进应力的试验方法设计了一个针对GaAs红外发光二极管的可靠性加速寿命的研究方案.这种方法主要是把步进应力和恒定应力两种方法相结合,用此来评估GaAs红外发光二极管的可靠度;然后总结除了GaAs红外发光二极管这种光电器件的寿命分布形式和失效模式.     

GaAs微波功率FET可靠性评价技术研究

为了使GaAs微波功率FET更可靠地应用于重要微波系统，选取高可靠器件生产线生产的CS0531型器件进行加速寿命试验，并研制了专用试验设备。观察到器件n因子随着试验时间有增大的趋势，初始低频噪声值与器件突然烧毁有一定的相关性。这一结果表明低频噪声有可能成为未来评价GaAs器件可靠性的一种方法。该器件失效机构激活能2．45eV，为道温度110℃时，10年平均失效率4Fit，平均寿命75137×1011h。     

砷化镓毫米波器件

叙述了GaAs MESFET、GaAs HEMT和GaAs耿氏器件等新一代GaAs毫米波器件的发展现状。     

化合物半导体器件与电路的研究进展

介绍了GaAs,InP和GaN等几种重要化合物半导体电子器件的特点、应用和发展前景。回顾了GaAs,InP和GaN材料的材料特性及其器件发展历程与现状。分别讨论了GaAs基HEMT由PHEMT渐变为MHEMT结构和性能的变化,GaAs基HBT在不同电路应用中器件的特性,InP基HEMT与HBT的器件结构及工作特性,GaN基HEMT与HBT的器件特性参数。总体而言,化合物半导体器件与电路在高功率和高频电子器件方面发展较快,GaAs,InP和GaN材料所制得的各种器件电路工作在不同的频率波段,其在相关领域发展潜力巨大。     

Compensation-circuit to improve radiation-hardness in GaAsdigital-circuits, based on X-ray studies

Earlier results have shown that GaAs devices do not exhibit appreciable degradation up to a radiation dose of nearly 10⁸ rad (GaAs). The results of this work suggest that GaAs devices and circuits are sensitive to radiation exposure at dose levels below 10⁸ rad(GaAs). Degradation was observed in E-MESFET and D-MESFET parameters and in circuit performance for devices which were designed and fabricated in a 1.2 μm GaAs process, when exposed to varying doses of 1.49 keV X-rays in the range 40-65 Mrad (GaAs). The degradation is attributed to the change in the properties of the MESFET channel region, caused by the transport of the atomic hydrogen from the passivation layer to the channel. A compensation circuit, based on the observed behavior of radiation effects on GaAs devices, has been designed to improve the radiation insensitivity of GaAs (E/D) based circuits under SPICE (Simulation Program with IC Emphasis) simulated conditions. Its usefulness is demonstrated through a DCFL inverter circuit up to nearly 10⁸ rad (GaAs) dose level. The results of this work can be used in the design of complex-function radiation-insensitive DCFL based circuits     

与砷化镓材料相依发展的微波半导体器件

本文从微波半导体器件的角度论述了砷化镓材料的重要性.砷化镓材料的发展过程是与微波器件的发展紧密联系在一起的.砷化镓材料每前进一步都导致微波器件性能的突破.文中在回顾了微波半导体器件发展历史的同时,指出砷化镓材料所起的重要作用.列举了砷化镓材料的特点,比较了几种制备方法,并给出了目前砷化镓微波器件研究和生产的现状、参数水平,最后对材料与器件的前景进行了初步估计.     

A comparative analysis of GaAs and Si ion-implanted MESFET's

In this work, numerical calculations of device characteristics including theI-Vcharacteristic, small-signal parameters, and cutoff frequency are reported for silicon-implanted MESFET devices. The device dimensions and impurity profile are similar to those of GaAs MESFET's. Although Si MESFET devices have not found practical applications, these calculations provide a good comparison of the intrinsic frequency limits of GaAs and Si. Comparative analysis shows that there are differences in the magnitude of the small-signal parameters and channel current between GaAs and Si MESFET devices with the same geometries and implanted profiles. However, the general variations of small-signal parameters with respect to the drain voltage is similar for both materials. In addition, the calculations show that a 1-µm channel length GaAs MESFET device has a higher cut-off frequency by a factor of 1.8 than a similar Si MESFET. These results indicate that GaAs devices are intrinsically better suited for very high-speed switching devices.     

Surface-Oriented Transferred-Electron Devices

The application of MESFET technology to the manufacturing of surface-oriented transferred-electron devices (TED's) with parmeters close to GaAs MESFET's is discussed. The limitations related to the contact resistance, fringing capacitance, domain formation time, impact ionization, and heat sinking are analyzed for GaAs and InP devices. Our estimates show that the surface-oriented devices can be used as microwave LSA generators at higher frequencies than the conventional LSA diodes. In a domain mode, the surface-oriented TED's can yield low values of the power-delay product comparable to those of GaAs MESFET's at higher speeds. The analysis of impact ionization within a high-field domain leads to a conclusion that even InP logic devices with practical lengths of the active layer can be manufactured with doping densities up to 10/sup 17/cm/sup -3/. The estimate of the temperature rise indicates that a CW operation is possible for practical device parameters. Because the parameters of surface-oriented TED's are similar to those of GaAs MESFET's they may be manufactured using the rapidly developing GaAs integrated-circuit technology and used in combination with GaAs MESFET's.     

Mobility, transit time and transconductance in submicrometre-gate-length m.e.s.f.e.t.s

Two-dimensional simulations of submicrometre-gate-length m.e.s.f.e.t.s of Si, GaAs and InP show that device transit time and transconductance depend more on high-field diffusion constant and the shape of the velocity/field characteristic than on low-field mobility. Reasonable InP devices have shorter transit times and higher transconductances than GaAs devices, and for certain device parameters these figures of merit can be almost the same for Si and GaAs devices.     

Backside copper metallization of GaAs MESFETs using TaN as thediffusion barrier

Backside copper metallization of GaAs MESFETs using TaN as the diffusion barrier was studied. A thin TaN layer of 40 nm was sputtered on the GaAs substrate before copper film metallization, as judged from the data of X-ray diffraction (XRD), Auger electron spectroscopy (AES), and cross-sectional transmission electron microscopy (TEM), the Cu/TaN films with GaAs were very stable without interfacial interaction up to 550°C annealing; the copper metallized MESFETs were thermally stressed at 300°C. The devices showed very little change in the device characteristics (<3%) after thermal stress, and the changes of the electrical parameters and RF characteristics of the devices after thermal stress were of the same order as those devices without Cu metallization, these results show that TaN is a good diffusion barrier for Cu in GaAs devices and the Cu/TaN films can be used for the backside copper metallization of GaAs MESFETs     

Low field mobility, effective saturation velocity and performance of submicron GaAs MESFETs

An analytical model is proposed which relates the transconductance of submicron GaAs MESFETs to a low field mobility, effective electron saturation velocity and device geometry and doping. The model predicts that the effective saturation velocity determines the performance of the devices at relatively high pinch-off voltages (Vpo > 5 V). At smaller pinch-off voltages (especially for enhancement-mode devices) the low field mobility becomes increasingly important, leading to additional advantages of GaAs devices over Si devices. Another prediction is a higher transconductance in thinner and higher-doped devices. This effect is also more important for devices with low pinch-off voltages. The obtained results may be used to deduce the effective values of the electron drift velocity in GaAs MESFETs as a function of the gate length.     

Fabrication and characterization of InGaP/GaAs heterojunction bipolar transistors on GOI substrates

In this letter, we report the first demonstration of InGaP/GaAs heterojunction bipolar transistors (HBTs) on germanium-on-insulator (GOI) substrates. We have performed physical characterization of the epitaxial layers to verify the high quality of the III-V epitaxial material grown on the GOI substrates and performed dc characterization of large-area InGaP/GaAs HBTs fabricated on the substrates. The InGaP/GaAs HBTs realized on GOI substrates were compared with identical devices grown on bulk germanium substrates and similar devices on semi-insulating GaAs substrates.