PHOTODETECTOR UNIT

FIELD: infrared radiation detection and recording. ^ SUBSTANCE: proposed photodetector unit that provides for reduction of one pixel bias current by approximately 10 - 50 times has at least one light-sensitive element in the form of multilayer heteroepitaxial semiconductor structure built around three-component solid solution CdHgTe incorporating permanent-composition effective layer corresponding to sensitivity gap of unit and disposed between two graded band-gap layers of same semiconductor material; gradient of graded band-gap layers is chosen proceeding from requirement to enlarge forbidden gap between effective layer and external edges of graded band-gap layers; it also has multiplexer affording read-out and processing of signal coming from light-sensitive element and interface made in the form of integrated circuit that functions to control multiplexer and to align multiplexer amplification and conversion channels; light-sensitive element and multiplexer are mounted in vacuum chamber opposite input aperture in immediate proximity of cold pin of cryogenic gas machine; light-sensitive element contacts are made in the form of indium columns connected to mating ones of multiplexer; the latter is disposed in hot gap. ^ EFFECT: enhanced voltaic sensitivity, eliminated extra noise with partially numbered cold gap signal and dc component of bias current dependent photoresistor signal. ^ 11 cl, 1 dwg