This report covers a program designed to realize the full potential of GaAs integrated circuits by expanding and improving fabrication and material techniques. The main accomplishment of the program was the successful implementation of the fabrication of integrated circuits on 3-inch diameter GaAs wafers. In addition, this program covered many activities related to GaAs IC processing. These include: work on semi-insulating material growth and characterization, investigation of ion implantation techniques (work carried out at the California Institute of Technology); evaluation of device uniformity, and investigation of its controlling factors; investigation of metallization yield and reliability, and improvements of processing techniques resulting from this study; design and testing of a multiplier and programmable shift registers/pattern generators; evaluation of mask programmable logic arrays to meet ERADCOMs needs for high performance communication systems; investigation of the hardness of GaAs ICs to total dose and transient ionizing radiation, and modelling of MESFET devices (this work carried out at North Carolina State University). (Author).
This report summarizes the research carried out at North Carolina State University in support of the Rockwell International Program on 'LSI-VLSI Ion Implanted Planar GaAs IC Processing. The major thrust of the program at NCSU was to develop accurate computer models for analyzing the performance of short-channel GaAs MESFET devices as used in the Rockwell VLSI circuits. The modeling research is divided into three parts: (1) Two-dimensional finite difference simulation, (2) Two-dimensional Monte Carlo analysis, and (3) Analytical modeling. The intent was to use the two-dimensional analyses to give exact solutions to the device operation and to serve as a guide for developing a simpler, and less expensive, analytical model of sufficient accuracy to be valuable as a design aid and to study effects of parameter changes.
Circuits critical to the performance of advanced radio, radar and spread spectrum communications systems require advances in the state-of-the-art in semiconductor technology to meet the demands of advanced systems. As these systems increase in complexity, extensive digital circuitry is required in addition to the typical linear signal processing circuits. The power, size and weight of advanced systems also becomes unacceptable without continuous advances in semiconductor technology. Moreover an increasing trend is seen in the use of metal mask selectable functions, programmable logic arrays and gate arrays to implement system specific circuitry in an attempt to lower non-recurring costs, minimize risk and shorten development times. GaAs and other technologies with very high speed power-performance figures-of-merit are critical ingredients in systems implementations which satisfy these needs. To meet these advanced system requirements this project was initiated as a multi-phase/year program to develop a group of mask programmable gallium arsenide (GaAs) circuit elements applicable to high speed/performance communications systems.
Even elementary school students of today know that electronics can do fan tastic things. Electronic calculators make arithmetic easy. An electronic box connected to your TV set provides a wonderful array of games. Electron ic boxes can translate languages! Electronics has even changed watches from a pair of hands to a set of digits. Integrated circuit (IC) chips which use transistors to store information in binary form and perform bin ary arithmetic make all of this possible. In just a short twenty years the field of integrated circuits has progressed from a few transistors per chip to thousands of transistors per chip. Since the early 1960's, the field has progressed from chips containing several transistors performing simple functions such as OR and AND functions to chips presently available which contain thousands of transistors performing a wide range of memory, control and arithmetic functions. The number of special journal issues, conferences, workshops, seminars, etc. related to the field of IC's is large. l~hile no single volume could adequately summarize the field, this volume attempts to provide a summary of some of the important issues and factors for Very Large Scale Integra tion (VLSI) from the perspective of several authors deeply involved in the field. In the field of VLSI, composed of many facets and disciplines, the de mand for engineers, physicists and chemists trained in IC skills exceeds supply.
In this book, a variety of topics related to Very-Large-Scale Integration (VLSI) is extensively discussed. The topics encompass the physics of VLSI transistors, the process of integrated chip design and fabrication and the applications of VLSI devices. It is intended to provide information on the latest advancement of VLSI technology to researchers, physicists as well as engineers working in the field of semiconductor manufacturing and VLSI design.
Gallium Arsenide technology has come of age. GaAs integrated circuits are available today as gate arrays with an operating speed in excess of one Gigabits per second. Special purpose GaAs circuits are used in optical fiber digital communications systems for the purpose of regeneration, multiplexing and switching of the optical signals. As advances in fabrication and packaging techniques are made, the operat ing speed will further increase and the cost of production will reach a point where large scale application of GaAs circuits will be economical in these and other systems where speed is paramount. This book is written for students and engineers who wish to enter into this new field of electronics for the first time and who wish to embark on a serious study of the subject of GaAs circuit design. No prior knowledge of GaAs technology is assumed though some previous experience with MOS circuit design will be helpful. A good part of the book is devoted to circuit analysis, to the extent that is possible for non linear circuits. The circuit model of the GaAs transistor is derived from first principles and analytic formulas useful in predicting the approxi mate circuit performance are also derived. Computer simulation is used throughout the book to show the expected performance and to study the effects of parameter variations.
The performance of high-speed semiconductor devices—the genius driving digital computers, advanced electronic systems for digital signal processing, telecommunication systems, and optoelectronics—is inextricably linked to the unique physical and electrical properties of gallium arsenide. Once viewed as a novel alternative to silicon, gallium arsenide has swiftly moved into the forefront of the leading high-tech industries as an irreplaceable material in component fabrication. GaAs High-Speed Devices provides a comprehensive, state-of-the-science look at the phenomenally expansive range of engineering devices gallium arsenide has made possible—as well as the fabrication methods, operating principles, device models, novel device designs, and the material properties and physics of GaAs that are so keenly integral to their success. In a clear five-part format, the book systematically examines each of these aspects of GaAs device technology, forming the first authoritative study to consider so many important aspects at once and in such detail. Beginning with chapter 2 of part one, the book discusses such basic subjects as gallium arsenide materials and crystal properties, electron energy band structures, hole and electron transport, crystal growth of GaAs from the melt and defect density analysis. Part two describes the fabrication process of gallium arsenide devices and integrated circuits, shedding light, in chapter 3, on epitaxial growth processes, molecular beam epitaxy, and metal organic chemical vapor deposition techniques. Chapter 4 provides an introduction to wafer cleaning techniques and environment control, wet etching methods and chemicals, and dry etching systems, including reactive ion etching, focused ion beam, and laser assisted methods. Chapter 5 provides a clear overview of photolithography and nonoptical lithography techniques that include electron beam, x-ray, and ion beam lithography systems. The advances in fabrication techniques described in previous chapters necessitate an examination of low-dimension device physics, which is carried on in detail in chapter 6 of part three. Part four includes a discussion of innovative device design and operating principles which deepens and elaborates the ideas introduced in chapter 1. Key areas such as metal-semiconductor contact systems, Schottky Barrier and ohmic contact formation and reliability studies are examined in chapter 7. A detailed discussion of metal semiconductor field-effect transistors, the fabrication technology, and models and parameter extraction for device analyses occurs in chapter 8. The fifth part of the book progresses to an up-to-date discussion of heterostructure field-effect (HEMT in chapter 9), potential-effect (HBT in chapter 10), and quantum-effect devices (chapters 11 and 12), all of which are certain to have a major impact on high-speed integrated circuits and optoelectronic integrated circuit (OEIC) applications. Every facet of GaAs device technology is placed firmly in a historical context, allowing readers to see instantly the significant developmental changes that have shaped it. Featuring a look at devices still under development and device structures not yet found in the literature, GaAs High-Speed Devices also provides a valuable glimpse into the newest innovations at the center of the latest GaAs technology. An essential text for electrical engineers, materials scientists, physicists, and students, GaAs High-Speed Devices offers the first comprehensive and up-to-date look at these formidable 21st century tools. The unique physical and electrical properties of gallium arsenide has revolutionized the hardware essential to digital computers, advanced electronic systems for digital signal processing, telecommunication systems, and optoelectronics. GaAs High-Speed Devices provides the first fully comprehensive look at the enormous range of engineering devices gallium arsenide has made possible as well as the backbone of the technology—ication methods, operating principles, and the materials properties and physics of GaAs—device models and novel device designs. Featuring a clear, six-part format, the book covers: GaAs materials and crystal properties Fabrication processes of GaAs devices and integrated circuits Electron beam, x-ray, and ion beam lithography systems Metal-semiconductor contact systems Heterostructure field-effect, potential-effect, and quantum-effect devices GaAs Microwave Monolithic Integrated Circuits and Digital Integrated Circuits In addition, this comprehensive volume places every facet of the technology in an historical context and gives readers an unusual glimpse at devices still under development and device structures not yet found in the literature.
