Recently, there has been a considerable upsurge of interest in heavily doped semiconductors. This interest is due primarily to the expanding range of applications of such. materials. Moreover, the heavy doping of semiconductors produces new effects (the forma tion of impurity aggregates, the appearance of allowed states in the forbidden band, etc J, which are of great interest in solid-state physics. The rapid growth in the number of papers on heavily doped semiconductors makes it difficult to review the results obtained so far. Therefore, many investigations carried out in 1966-7, par ticularly those on AIIIBV semiconductors, are not discussed in the present monograph, which represents the state of the knowledge in 1965. Nevertheless, the author hopes that, in spite of this, the book will be useful. An attempt is made, first, to review investigations of heavily doped semiconductors from a certain viewpoint and, sec ondly, to suggest some ideas (Chap. 5) which may be controversial but which are intended to stimulate further studies of heavily doped semiconductors which can be regarded as a special case of dis ordered systems. The work of American scientists investigating heavily doped semiconductors, in particular the efforts of E. O. Kane, J. 1. Pan kove, R. N. Hall, R. A. Logan, W. G. Spitzer, F. A. Trumbore, and many others, is well known to Soviet investigators. It gives me pleasure to learn that Western readers will now have an - v vi PREFACE portunity to become acquainted with the work done in the USSR.

First-generation semiconductors could not be properly termed "doped- they were simply very impure. Uncontrolled impurities hindered the discovery of physical laws, baffling researchers and evoking pessimism and derision in advocates of the burgeoning "pure" physical disciplines. The eventual banish ment of the "dirt" heralded a new era in semiconductor physics, an era that had "purity" as its motto. It was this era that yielded the successes of the 1950s and brought about a new technology of "semiconductor electronics". Experiments with pure crystals provided a powerful stimulus to the develop ment of semiconductor theory. New methods and theories were developed and tested: the effective-mass method for complex bands, the theory of impurity states, and the theory of kinetic phenomena. These developments constitute what is now known as semiconductor phys ics. In the last fifteen years, however, there has been a noticeable shift towards impure semiconductors - a shift which came about because it is precisely the impurities that are essential to a number of major semiconductor devices. Technology needs impure semiconductors, which unlike the first-generation items, are termed "doped" rather than "impure" to indicate that the impurity levels can now be controlled to a certain extent.

This is the first book to describe thoroughly the many facets of doping in compound semiconductors. Equal emphasis is given to the fundamental materials physics and to the technological aspects of doping. The author describes various doping techniques, including doping during epitaxial growth, doping by implantation, and doping by diffusion. The key characteristics of all dopants that have been employed in III-V semiconductors are discussed. In addition, general characteristics of dopants are analyzed, including the electrical activity, saturation, amphotericity, autocompensation, and maximum attainable dopant concentration. Redistribution effects are important in semiconductor microstructures. Linear and non-linear diffusion, different microscopic diffusion mechanisms, surface segregation, surface drift, surface migration, impurity-induced disordering, and the respective physical driving mechanisms are illustrated. Topics related to basic impurity theory include the hydrogenic model for shallow impurities, linear screening, density of states, classical and quantum statistics, the law of mass action, as well as many analytic approximations for the Fermi-Dirac integral for three-, two- and one dimensional systems. The timely topic of highly doped semiconductors, including band tails, impurity bands, bandgap renormalization, the Mott transition, and the Burstein-Moss shift, is discussed as well. Doping is essential in many semiconductor heterostructures including high-mobility selectively doped heterostructures, quantum well and quantum barrier structures, doping superlattice structures and d-doping structures. Technologically important deep levels are summarized, including Fe, Cr, and the DX-center, the EL2 defect, and rare-earth impurities. The properties of deep levels are presented phenomenologically, including emission, capture, Shockley-Read recombination, the Poole-Frenkel effect, lattice relaxation, and other effects. The final chapter is dedicated to the experimental characterization of impurities. This book will be of interest to graduate students, researchers and development engineers in the fields of electrical engineering, materials science, physics, and chemistry working on semiconductors. The book may also be used as a text for graduate courses in electrical engineering and materials science.

The importance of the effective mass (EM) is already well known since the inception of solid-state physics and this first-of-its-kind monograph solely deals with the quantum effects in EM of heavily doped (HD) nanostructures. The materials considered are HD quantum confined nonlinear optical, III-V, II-VI, IV-VI, GaP, Ge, PtSb2, stressed materials, GaSb, Te, II-V, Bi2Te3, lead germanium telluride, zinc and cadmium diphosphides, and quantum confined III-V, II-VI, IV-VI, and HgTe/CdTe super-lattices with graded interfaces and effective mass super-lattices. The presence of intense light waves in optoelectronics and strong electric field in nano-devices change the band structure of semiconductors in fundamental ways, which have also been incorporated in the study of EM in HD quantized structures of optoelectronic compounds that control the studies of the HD quantum effect devices under strong fields. The importance of measurement of band gap in optoelectronic materials under intense external fields has also been discussed in this context. The influences of magnetic quantization, crossed electric and quantizing fields, electric field and light waves on the EM in HD semiconductors and super-lattices are discussed.The content of this book finds twenty-eight different applications in the arena of nano-science and nano-technology. This book contains 200 open research problems which form the integral part of the text and are useful for both PhD aspirants and researchers in the fields of condensed matter physics, materials science, solid state sciences, nano-science and technology and allied fields in addition to the graduate courses in semiconductor nanostructures. The book is written for post-graduate students, researchers, engineers and professionals in the fields of condensed matter physics, solid state sciences, materials science, nanoscience and technology and nanostructured materials in general.

The NATO Advanced Study Institute on "Molecular Beam Epitaxy (MBE) and Heterostructures" was held at the Ettore Majorana Center for Scientific Culture, Erice, Italy, on March 7-19, 1983, the second course of the International School of Solid-State Device Re search. This volume contains the lectures presented at the Institute. Throughout the history of semiconductor development, the coupling between processing techniques and device structures for both scientific investigations and technological applications has time and again been demonstrated. Newly conceived ideas usually demand the ultimate in existing techniques, which often leads to process innova tions. The emergence of a process, on the other hand, invariably creates opportunities for device improvement and invention. This intimate relationship between the two has most recently been witnessed in MBE and heterostructures, the subject of this Institute. This volume is divided into several sections. Chapter 1 serves as an introduction by providing a perspective of the subject. This is followed by two sections, each containing four chapters, Chapters 2-5 addressing the principles of the MBE process and Chapters 6-9 describ ing its use in the growth of a variety of semiconductors and heteros tructures. The next two sections, Chapters to-II and Chapters 12-15, treat the theory and the electronic properties of the heterostructures, respectively. The focus is on energy quantization of the two dimensional electron system. Chapters 16-17 are devoted to device structures, including both field-effect transistors and lasers and detec tors.

Optical properties, particularly in the infrared range of wavelengths, continue to be of enormous interest to both material scientists and device engineers. The need for the development of standards for data of optical properties in the infrared range of wavelengths is very timely considering the on-going transition of nano-technology from fundamental R&D to manufacturing. Radiative properties play a critical role in the processing, process control and manufacturing of semiconductor materials, devices, circuits and systems. The design and implementation of real-time process control methods in manufacturing requires the knowledge of the radiative properties of materials. Sensors and imagers operate on the basis of the radiative properties of materials. This book reviews the optical properties of various semiconductors in the infrared range of wavelengths. Theoretical and experimental studies of the radiative properties of semiconductors are presented. Previous studies, potential applications and future developments are outlined. In Chapter 1, an introduction to the radiative properties is presented. Examples of instrumentation for measurements of the radiative properties is described in Chapter 2. In Chapters 3-11, case studies of the radiative properties of several semiconductors are elucidated. The modeling and applications of these properties are explained in Chapters 12 and 13, respectively. In Chapter 14, examples of the global infrastructure for these measurements are illustrated.

Power Electronics Device Applications of Diamond Semiconductors presents state-of-the-art research on diamond growth, doping, device processing, theoretical modeling and device performance. The book begins with a comprehensive and close examination of diamond crystal growth from the vapor phase for epitaxial diamond and wafer preparation. It looks at single crystal vapor deposition (CVD) growth sectors and defect control, ultra high purity SC-CVD, SC diamond wafer CVD, heteroepitaxy on Ir/MqO and needle-induced large area growth, also discussing the latest doping and semiconductor characterization methods, fundamental material properties and device physics. The book concludes with a discussion of circuits and applications, featuring the switching behavior of diamond devices and applications, high frequency and high temperature operation, and potential applications of diamond semiconductors for high voltage devices. - Includes contributions from today's most respected researchers who present the latest results for diamond growth, doping, device fabrication, theoretical modeling and device performance - Examines why diamond semiconductors could lead to superior power electronics - Discusses the main challenges to device realization and the best opportunities for the next generation of power electronics