A GaAs MCM power amplifier of 3.6 V operation with high efficiencyof 49% for 0.9 GHz digital cellular phone systems

An extremely small GaAs PA (power amplifier) has been implemented using AlN multilayer MCM for 0.9 GHz digital cellular phones. The present PA exhibited high efficiency of 49% with drain supply voltage as low as 3.6 V. This PA was designed to provide matching circuits with the maximum gain at the input side and the minimum intermodulation distortion at the output side. Nonlinear simulation result verifies that this matching condition provides the lowest π/4-shift QPSK distortion and indicates that the phase shift of the amplifier is mainly caused by source-drain resistance     

60 GHz multi-chip-module receiver with substrate integrated waveguide antenna and filter

A compact 60 GHz MCM receiver has been demonstrated by integrating millimetre-wave substrate-integrated waveguides and GaAs MMICs for the first time. The module includes a waveguide antenna and filter, MMIC LNA and mixer, and lumped elements for IF filtering embedded into the multilayer photo-imageable thick-film substrate. Cavities for MMIC attachment are photo-imaged as part of the standard process.     

GaAs IC CAD及其在通信电路中的应用技术

介绍了自主开发的多个完整实用的 Ga As IC CAD软件 ,包括微波无源元件建模、微波有源器件测试建模、微波毫米波 IC CAD、光电集成电路 CAD、 Ga As VHSIC CAD、微波高速 MCM CAD等 ,并简要介绍了针对 Ga As工艺线的建库工作。以上软件和库已用于多个通信电路的设计。     

Monolithic integration of optoelectronic, electronic and passive components in GaAlAs/GaAs multilayers

The monolithic integration of LEDs, detectors, waveguides, resistors and FETs has been demonstrated in GaAlAs/GaAs multilayer structures. The resulting uncommitted optoelectronic integrated circuits have been operated in transmitter, receiver and repeater configurations.     

微波集成电路技术—回顾与展望

半个多世纪来 ,微波电路技术经历了从分立电路、两维微波集成电路、三维微波集成电路等阶段。在回顾这一发展历程后 ,介绍多层微波集成电路和三维微波集成电路。阐述其产生背景、关键技术及发展方向。文中将涉及微加工技术以及从直流至射频的多芯片全集成新概念。瞻望二十一世纪前景。     

Artificial Neural Network Models for the Double-Vias in Multilayer Stripline Circuits

Multi-vias is a kind of interconnection largely existing in the multi-chip module (MCM) packages for high-speed digital circuits. In this paper, a multilayer perceptron neural network (MLPNN) is used to model the double-vias in multilayer stripline circuits. The MLPNN is electromagnetically developed with a set of training data that are produced by the full-wave finite-difference time-domain (FDTD) method. One type of the designs of experiments, the central composite technique, is used to allow for a minimum number of FDTD simulations that is needed to be performed.     

New high-speed III-V devices for integrated circuits

This paper traces the research and development steps that led to selectively doped heterostructure transistors and integrated circuits. The transistor is the fastest switching transistor known, whereas integrated circuits built with the device outperform all other circuits of equivalent function. The work began with studies of GaAs optical spectroscopy at low temperatures using (Al, Ga)As-GaAs-(Al, Ga)As heterostructures to obtain micrometer-thick GaAs layers for absorption measurements. To prepare thinner layers, a multilayer (Al, Ga)As/GaAs structure containing 10 or 20 GaAs layers interleaved with (Al, Ga)As support layers were grown. With ∼200-Å-thick GaAs layers, the absorption spectrum at 2 K showed quantization of electron motion. Doping experiments resulted in the concept of doping the wider band-gap (Al, Ga)As to supply carriers to the undoped narrower bandgap GaAs. The removal of impurities from the GaAs layer results in higher carrier mobility due to greatly reduced impurity scattering. This technique, called modulation doping, resulted in a new generation of higher speed devices and circuits. The basic device is known as a selectively doped heterostructure transistor or SDHT.     

Etching behavior of GaAs/AlGaAs multilayer structure during laser beam scanning

The thermochemical etching behavior of GaAs/AlGaAs multilayer structure during laser beam scanning has been studied. The etch rate changes between GaAs and AlGaAs epilayers as the etching process proceeds through the layered sample. The phenomenon can be explained by the difference of thermal parameters of the heterojunction interface. The local temperature rise from laser irradiation has been calculated to investigate etching characteristics for GaAs and AlGaAs. It is concluded that the good thermal confinement at GaAs/AlGaAs interface produces the wider etch width of GaAs layer than that of AlGaAs layer in GaAs/AlGaAs multilayer. The maximum etch rate of the GaAs/AlGaAs multilayer was 32.5 μm/sec and the maximum etched width ratio of GaAs to AlGaAs was 1.7.     

Laser-based electro-optic testing of multichip module structures

Laser-based electro-optic probing is a proven noninvasive technique for testing high-speed microwave circuits on substrates such as gallium arsenide (GaAs) and indium phosphide (InP). We have extended this technique to probe circuit structures on doped and poled polyimide substrates that are useful in high-density packaging applications such as multichip modules (MCMs). Our results demonstrate the potential to improve the testability of MCMs by probing circuit structures that are buried in the central layers of an MCM. In addition to direct, point-by-point electric field measurements in representative MCM structures, we have investigated the poled polyimide dielectric efficacy both as a dielectric circuit layer and as a suitable electro-optic material.     

A GaAs Schottky-barrier photodiode with high quantumefficiency-bandwidth product using a multilayer reflector

A GaAs Schottky-barrier with high quantum efficiency-bandwidth product has been developed by using a GaAs/Al_0.25Ga_0.75 As multilayer reflector. The multilayer reflector structure wa designed by using the scattering matrix method. By growing four pairs of Al_0.25Ga_0.75As (825 Å)/GaAs (330 Å) multilayer reflectors between the undoped GaAs active layer and the buffer layer, a responsivity of 0.6 A/W at λ=0.84 μm was obtained for this device. This represents a 30% improvement over the device without a multilayer reflector. The response speed of the photodiode was measured by the impulse response method, and the results yielded a rise time of 38.45 ps, corresponding to a bandwidth of 9 GHz for this detector     

分子束外延生长的GaAs-Al_xGa_(1-x)As多层异质结构中的“精细低维调制条纹”的观察

应用透射式电子显微镜观察了GaAs-Al_xGa_(1-x)As多层异质结结构中的“精细低维调制条纹”。在邻近GaAs-Al_xGa_(1-x)As超晶格层的缓冲层中和与这缓冲层邻近的GaAs-Al_xGa_(1-x)As超晶格层的小区域中发现了等宽度的“精细低维调制条纹”,其宽度为9.1(?)的GaAs条纹,12(?)的Al_xGa_(1-x)As条纹。文中介绍了用显微密度计获得的这些条纹的密度分布结果。同时还给出了GaAs-Al_xGa_(1-x)As 多层异质结结构的晶格像和用X射线能量散射谱技术获得的成分定量分析结果。     

High speed GaAs integrated circuits

Much interest has been expressed in the use of GaAs MESFET's for high speed digital integrated circuits (IC's). Propagation delays in the 60- to 90-ps/gate range have been demonstrated by several laboratories on SSI and MSI logic circuits. Recently, large scale digital IC's with over 1000 gates have been demonstrated in GaAs. In this review paper, the device, circuit, and processing approaches presently being explored for high speed GaAs digital circuits are presented. The present performance status of high speed circuits and LSI circuits is reviewed.     

多层共烧陶瓷在MCM-C中的应用及其可靠性

评述了应用于MCM-C的多层共烧陶瓷的材料选择、工艺过程与控制，通过对芯片组件系统的应力失效、损伤机理、热分析及关键工艺的过程控制的探讨，试图找出多层共烧陶瓷对MCM的可靠性的影响。     

分子束外延生长的GaAs-AlxGa1-xAs多层异质结构中的“精细低维调制条纹”的观察

应用透射式电子显微镜观察了GaAs-Al_xGa_1-xAs多层异质结结构中的“精细低维调制条纹”。在邻近GaAs-Al_xGa_1-xAs超晶格层的缓冲层中和与这缓冲层邻近的GaAs-Al_xGa_1-xAs超晶格层的小区域中发现了等宽度的“精细低维调制条纹”,其宽度为9.1Å的GaAs条纹,12Å的Al_xGa_1-xAs条纹。文中介绍了用显微密度计获得的这些条纹的密度分布结果。同时还给出了GaAs-Al_xGa_1-xAs 多层异质结结构的晶格像和用X射线能量散射谱技术获得的成分定量分析结果。     

MCM的现状、展望与对策

描述了ＭＣＭ的现状和未来发展趋势，指出ＭＣＭ正在从数字电路逐渐向模拟电路，尤其是微波电路移动。并对发展我国ＭＣＭ提出了几点建议。     

Development of microwave multilayer plastic-based multichip modules

We present the design and development of multilayer plastic-based multichip modules (MCM) at microwave frequencies. A vertical feed-through interconnect, which consists of embedded copper wires in plastic, has been developed to transport RF/microwave and dc signals from the first to the second packaging level. The development of this vertical feed-through enables plastic modules to be configured in a surface mount topology that can be interfaced with low cost FR-4 boards using ball grid arrays (BGA). The experimental analysis results demonstrate that this vertical feed-through used with BGAs has ultra-low parasitics and achieves a return loss of greater than 20-dB at 4-GHz. In addition, we demonstrate a number of packaged active microwave circuits including a switch, a low noise amplifier (LNA) and a power amplifier using the plastic module technology at microwave frequencies     

C频段内匹配砷化镓功率场效应晶体管

采用离子注入、多层欧姆接触金属结构、干法刻蚀、г形栅、空气桥、通孔接地和电镀热沉等先进技术，在直径５０ｍｍＧａＡｓ片上制作了总栅宽为９．６ｍｍ的功率场效应晶体管芯片。用４枚这种芯片并联，在其输入端和输出端分别加入内匹配电路，制成了Ｃ频段内匹配功率场效应晶体管。在大于５００ＭＨｚ的带宽内，１ｄＢ增益压缩输出功率达１８Ｗ，１ｄＢ压缩增益为８．３ｄＢ，功率附加效率达３０％。     

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     

AlN多层基板的研制

MCM技术推动了现代微电子技术迅猛发展,已广泛应用于各种通讯系统的收发组件之中。AIN基板作为MCM技术多层基板主流之一,由于其高热导率、与硅片匹配的热膨胀系数、高介电常数、兼容各种芯片组装工艺的优点,在各个领域均获得了广泛的应用。文章结合一个微波组件AIN基板的研制,阐述了在AIN基板研制过程中解决的工艺难点,如粉料配制、流延、层压、烧结等,对研制的AIN基板进行了物理性能与电性能测试,结果表明AIN基板完全可以满足大功率毫米波／微波组件的实用化要求。     

GaAs HBT's for microwave integrated circuits

The status of the microwave GaAs heterojunction bipolar transistor (HBT) technology is reviewed. Microwave circuits for advanced military and commercial systems continue to increase their dependence on the performance, functionality, and cost of active components fabricated using solid-state technology. The performance advantages provided by GaAs HBT's, for several critical circuit applications, have stimulated a worldwide development activity. Progress in HBT device technology and microwave circuit applications has been extremely rapid because of the broad availability of III-V compound semiconductor epitaxial materials and prior experience with GaAs field-effect transistors (FET's) and monolithic microwave integrated circuits (MMIC's). The great flexibility of HBT's in microwave circuits makes them prime candidates for applications in complex multifunctional microwave/digital IC's in next-generation systems