Single Crystal Photoconductive Detectors in Lead Selenide

Abstract

Near intrinsic single crystals of grown from the vapor have been used to construct photoconductive detectors for operation at room temperature. Fabrication of the detectors depends on the use of a newly developed chemical etch to reduce the specimens to thicknesses of a few microns, and to provide surfaces with low carrier recombination velocity. The highest detectivity, , achieved was ; Various methods of estimating bulk carrier lifetimes have been used; the value for the best crystal measured was in excess of 4 μsec. The surface recombination velocity of the best etched surface was below 80 cm sec−1. Similar etches can be used for and .