Compound And Josephson High Speed Devices

In recent years, III-V devices, integrated circuits, and superconducting integrated circuits have emerged as leading contenders for high-frequency and ultrahigh speed applications. GaAs MESFETs have been applied in microwave systems as low-noise and high-power amplifiers since the early 1970s, replacing silicon devices. The heterojunction high-electron-mobility transistor (HEMT), invented in 1980, has become a key component for satellite broadcasting receiver systems, serving as the ultra-low-noise device at 12 GHz. Furthermore, the heterojunction bipolar transistor (HBT) has been considered as having the highest switching speed and cutoff frequency in the semiconductor device field. Initially most of these devices were used for analog high-frequency applications, but there is also a strong need to develop high-speed III-V digital devices for computer, telecom munication, and instrumentation systems, to replace silicon high-speed devices, because of the switching-speed and power-dissipation limitations of silicon. The potential high speed and low power dissipation of digital integrated circuits using GaAs MESFET, HEMT, HBT, and superconducting Josephson junction devices has evoked tremendous competition in the race to develop such technology. A technology review shows that Japanese research institutes and companies have taken the lead in the development of these devices, and some integrated circuits have already been applied to supercomputers in Japan. The activities of Japanese research institutes and companies in the III-V and superconducting device fields have been superior for three reasons. First, bulk crystal growth, epitaxial growth, process, and design technology were developed at the same time.

This book examines the physical principles behind the operation of high-speed transistors operating at frequencies above 10 GHz and having switching times less than 100 psec. If the 1970s cannot be remembered for the opportunities for creating and extensively using transistors operating at such high speeds, then, the situation has changed radically because of rapid progress in sub micrometer technology for manufacturing transistors and integrated circuits from GaAs and other semiconductor materials and the powerful influx of new physical concepts. Not only have transistors having switching speeds of 50-100 psec operating in the 10-20 GHz region been created in recent years, but the possibilities for manufacturing transistors operating one to two orders of magnitude faster have been revealed. As superhigh-speed transistors have been created, many of the most important areas of technology such as communications, computing technology, television, radar, and the manufacture of scientific, industrial, and medical equipment have qualitatively changed. Microwave transistors operating at millimeter wavelengths make it possible to produce compact and highly efficient equipment for communications and radar technology. Transistors with switching speeds better than 10-100 psec make it possible to increase the speed of microprocessors and other computer components to tens of billions of operations per second and thereby solve one of the most pressing problems of modern electronics - increasing the speed of digital information processing.

With the advent of High Temperature Superconductivity and the increasing reliability of fabrication techniques, superconductor technology has moved firmly into the mainstream of academic and industrial research. There is currently no single source of practical information giving guidance on which technique to use for any particular category of superconductor. An increasing number of materials scientists and electrical engineers require easy access to practical information, sensible advice and guidance on 'best-practice' and reliable, proven fabrication and characterisation techniques.The Handbook will be the definitive collection of material describing techniques for the fabrication and analysis of superconducting materials. In addition to the descriptions of techniques, authoritative discussions written by leading researchers will give guidance on the most appropriate technique for a particular situation.Characterisation and measurement techniques will form an important part of the Handbook, providing researchers with a standard reference for experimental techniques. The tutorial style description of these techniques makes the Handbook particularly suitable for use by graduate students.The Handbook will be supported by a comprehensive web site which will be updated with new data as it emerges.The Handbook has six main sections: -- Fundamentals of Superconductivity - characteristic properties, elementary theory, critical current of type II superconductors-- Processing - bulk materials, wires and tapes, thick and think films, contact techniques-- Characterisation Techniques - structure/microstructure, measurement and interpretation of electromagnetic properties,measurement of physics properties-- Materials - characteristic properties of low and high Tc materials-- Applications - high current applications, trapped flux devices, high frequency devices, josephson junction devic

This report was prepared by Hughes Aircraft Company, Culver City, California under Contract No. F33615-70-C-1348. The work was administered under the direction of the Air Force Materials Laboratory, Air Force Systems Cornrnand, Wright-Patterson Air Force Base, Ohio, with Mr. B. Emrich, Project Engineer. The Electronic Properties Information Center (EPIC) is a designated inforrnation Analysis Center of the Departrnent of Defense, authorized to provide inforrnation to the entire DoD cornrnunity. The purpose of the Center is to provide a highly competent source of inforrnation and data on the electronic, optical and magnetic properties of materials of value to the Department of Defense. Its major function is to evaluate, compile and publish the experimental data from the world's unclassified literature concerned with the properties of materials. All materials relevant to the field of electronics are within the scope of EPIC: insulators, semiconductors, metals, superconductors, ferrites, ferroelectrics, ferromagnetics, electro luminescents, therrnionic emitters and optical materials. The Center's scope includes inforrnation on over 100 basic properties of materials; information generally regarded as being in the area of devices and/or circuitry is excluded. Grateful acknowledgement is made for the review and comments of Dr. G. D. Cody of RCA Laboratories and Dr. B. W. Roberts of General Electric Co. V CONTENTS Introduction •. . ••••. . . ••••. . . . . . •• 1 Superconductivity Applications •••• 3 Niobium-Hydrogen •. . ••. •. ••. ••. . •• 15 Niobium-Antimony. • . . . • . • • • • . • • . • • .