Physics Of Amorphous Semiconductors

This is a useful textbook for graduate students in the fields of solid state physics and chemistry as well as electronic engineering. Presenting the fundamentals of amorphous semiconductors clearly, it will be essential reading for young scientists intending to develop new preparation techniques for more ideal amorphous semiconductors e.g. a-Si:H, to fabricate stable and efficient solar cells and thin film transistors and new artificial amorphous materials such as multilayers for quantum devices.A large portion is devoted to the latest developments of amorphous semiconductors including electronic properties of a-Si:H, nature of weak bonds and gap states in a-Si:H, mechanisms for light-induced defect creation in a-Si:H and chalcogenides, quantum phenomena in multilayer films.

This comprehensive, detailed treatise on the physics and applications of the new emerging technology of amorphous semiconductors focuses on specific device research problems such as the optimization of device performance. The first part of the book presents hydrogenated amorphous silicon type alloys, whose applications include inexpensive solar cells, thin film transistors, image scanners, electrophotography, optical recording and gas sensors. The second part of the book discusses amorphous chalcogenides, whose applications include electrophotography, switching, and memory elements. This book will serve as an excellent reference source for solid state scientists and engineers, and as a useful self-contained introduction to the field for graduate students.

The Kyoto Summer Institute 1980 (KSI '80), devoted to "Fundamental Physics of Amorphous Semiconductors", was held at Research Institute for Fundamental Physics (RIFP), Kyoto University, from 8-11 September, 1980. The KSI '80 was the successor of the preceding Institutes which were held in July 1978 on "Particle Physics and Accelerator Projects" and in September 1979 on "Physics of Low-Dimensional Systems". The KSI '80 was attended by 200 participants, of which 36 were from abroad: Canada, France, Korea, Poland, U.K., U.S.A, U.S.S.R., and the Federal Republic of Germany. The KSI '80 was organized by RIFP and directed by the Amorphous Semicon ductor group in Japan. A few years ago, we started to organize an interna tional meeting on amorphous semiconductors' as a satell ite meeting of the International Conference on "Physics of Semiconductors" held on September 1-5, 1980 in Kyoto. We later decided to hold the meeting in the form of the Kyoto Summer Institute. The Kyoto Summer Institute is aimed to be something between a school and a conference. Accordingly, the object of the KSI '80 was to provide a series of invited lectures and informal seminars on fundamental physics of amorphous semiconductors. No contributed paper was accepted, but seminars were open.

Amorphous semiconductors are subtances in the amorphous solid state that have the properties of a semiconductor and which are either covalent or tetrahedrally bonded amorphous semiconductors or chelcogenide glasses. Developed from both a theoretical and experimental viewpoint Deals with, amongst others, preparation techniques, structural, optical and electronic properties, and light induced phenomena Explores different types of amorphous semiconductors including amorphous silicon, amorphous semiconducting oxides and chalcogenide glasses Applications include solar cells, thin film transistors, sensors, optical memory devices and flat screen devices including televisions

Solid state physics after solving so successfully many fundamental problems in perfect or slightly imperfect crystals, tried in recent years to attack problems associated with large disorder with the aim to understand the consequences of the lack of the long-range order. Semiconductors are much more changed by disorder than metals or insulators, and appear to be the most suitable materials for fundamental work. Considerable exploratory work on amorphous and liquid semiconductors was done by the Leningrad School since the early fifties. In recent years, much research in several countries was directed to deepen the understanding of the structural, electronic, optical, vibrational, magnetic and other proper ties of these materials and to possibly approach the present level of under standing of crystalline semiconductors. This effort was stimulated not only by purely scientific interest but also by the possibility of new applications from which memory devices in the general sense are perhaps the most challenging. The research met with serious difficulties which are absent in crystals.

This book was written to be an introduction to the science of amorphous materials. It is aimed at final year undergraduates, beginning graduate students and researchers in solid-state physics or chemistry, materials science or engineering.

Optical Properties of Crystalline and Amorphous Semiconductors: Materials and Fundamental Principles presents an introduction to the fundamental optical properties of semiconductors. This book presents tutorial articles in the categories of materials and fundamental principles (Chapter 1), optical properties in the reststrahlen region (Chapter 2), those in the interband transition region (Chapters 3 and 4) and at or below the fundamental absorption edge (Chapter 5). Optical Properties of Crystalline and Amorphous Semiconductors: Materials and Fundamental Principles is presented in a form which could serve to teach the underlying concepts of semiconductor optical properties and their implementation. This book is an invaluable resource for device engineers, solid-state physicists, material scientists and students specializing in the fields of semiconductor physics and device engineering.