Editorial Note Regarding Semiconductors

Editorial Note regarding Semiconductors LL but one of the papers that comprise this issue discuss practical aplications of semiconductors and touch upon their properties as employed in rectifying devices, detectors, and in a new amplifying unit--the so-called transistor. These semiconductor papers all relate to one another and present, as a whole, a current but well developed account of the behavior and uses of these very promising additions to today's vast array of electrical applicances. Because semiconductors are relative newcomers, few engineers have as yet had occasion to become familiar with their characteristics and the reasons for their somewhat unexpected performance. Accordingly, it seems appropriate to preface the present group of papers with a brief introductory note devoted to the nature of the physical phenomena encountered. The semiconductors of interest in the communications art are electronic rather than ionic conductors, and include copper oxide, various other oxides, selenium, germanium and silicon. Being electronic conductors, the constituent atoms remain in fixed positions. They may lose or gain electrons during the conduction process but the structure of the conductor as a whole and its chemical composition are not affected. Basic to the theory of these semiconductors is the idea that electrons can carry current in two distinguishable and distinctly different ways: one being called "excess conduction," "conduction by excess electrons," or simply "conduction by electrons;" and the other being called "deficit conduction" or "conduction by holes." The possibility that these two processes may be simultaneously and separably active in a semiconductor affords a basis for explaining transistor action.