A 10-Year Retrospective

The field of narrow-gap II-VI materials is dominated by lhe compound mercury cadmium telluride, MCT or Hg1_ .. Cd .. Te. By varying the x value, material can be made to cover all the important infrared (lR) ranges of interest. It is probably true to say that MCT is the third most studied semiconductor after silicon and gallium arsenide. As current epitaxial layers of MCT are mainly grown on bulk CdTe family substrates these materials are included in this book, although strictly, of course, they are not 'narrow-gap'. This book is intended for readers who are either new to the field or are experienced workers in the field who need a comprehensive and up to date view of this rapidly expanding area. To satisfy the needs of the frrst group each chapter discusses the principles underlying each topic and some of the historical background before bringing the reader the most recent information available. For those currently in the field the book can be used as a collection of useful data, as a guide to the literature and as an overview of topics covering the wide range of work areas.

This book is intended for readers desiring a comprehensive analysis of the latest developments in widegap II-VI materials research for opto-electronic applications and basic insight into the fundamental underlying principles. Therefore, it is hoped that this book will serve two purposes. Firstly, to educate newcomers to this exciting area of physics and technology and, secondly, to provide specialists with useful references and new insights in related areas of II-VI materials research. The motivation for preparing this book originated from the need for a current review of this fertile and important field. A primary goal of this book is therefore to present an eclectic synthesis of these sometimes diverse fields of investigation. This book consists of three main sections, namely (1) Growth and Properties, (2) Materials Characterization and (3) Devices. Part One presents an overall perspective of the state of the art in the preparation of the widegap II-VI materials. Part Two concentrates on current topics pertinent to the characterization of these materials from the unique perspective of each of the authors. Part Three focuses on advances in the opto-electronic applications of these materials. The material in this section runs the gamut from addressing recent advances in device areas which date back to some of the earliest reported research in these materials, to tackling some quite new and exciting future directions.

Volume 1 of Point Defects in Solids has as its major emphasis defects in ionic solids. Volume 2 now extends this emphasis to semiconductors. The first four chapters treat in some detail the creation, kinetic behavior, inter actions, and physical properties of both simple and composite defects in a variety of semiconducting systems. Also included, as in Vol. 1, are chapters on special topics, namely phonon-defect interactions and defects in organic crystals. Defect behavior in semiconductors has been a subject of considerable interest since the discovery some twenty-five years ago that fast neutron irradiation profoundly affected the electrical characteristics of germanium and silicon. Present-day interest has been stimulated by such semiconductor applications as solar cell power plants for space stations and satellites and semiconductor particle and y-ray detectors, since in both radiation damage can cause serious deterioration. Of even greater practical concern is the need to understand particle damage in order to capitalize upon the develop ing technique of ion implantation as a means of device fabrication. Although the periodic international conferences on radiation effects in semiconductors have served the valuable function of summarizing the extensive work being done in this field, these proceedings are much too detailed and lack the background discussion needed to make them useful to the novice.