Semiconductor photoelectric converters for the ultraviolet region of the spectrum

Recently, ultraviolet photoelectronics emerged in response to the needs of medicine, biology, military equipment, and the problem of the hole in the ozone layer. A specific feature of this field of photoelectronics is the need to detect weak (albeit appreciably affecting vital human functions) signals against a background of intense radiation in the visible and infrared regions of the spectrum. Ultraviolet electronics relies on Si-based p-n structures and GaP-based Schottky barriers, p-n structures and Schottky barriers based on GaN and AlGaN (solar-blind, i.e., solar-radiation-insensitive devices), SiC structures with potential barriers (high-temperature devices), and ZnO- and ZnS-based photoresistors and Schottky diodes. In this review, the parameters of starting wide-gap semiconductors are given, physical foundations for photoelectric conversion and the principles of formation of ohmic contacts are described, characteristics of corresponding devices are given, and the envisaged lines of further studies are outlined. (C) 2003 MAIK Nauka / Interperiodica.