Carrier Lifetime in Photoconductive InAs

Abstract

The majority carrier lifetime associated with the photoconductivity of heavily doped n-type InAs has been found to depend exponentially on the reciprocal absolute temperature between 300°K and 140°K. Lifetimes were found to range from 10−8 sec at 300°K to nearly 10−3 sec at 100°K. Measurements indicate that lifetime is determined by recombination centers located 0.23 eV below the conduction band that are probably ionized donors. The temperature dependence of the lifetime above 140°K is interpreted in terms of the temperature variation of the recombination center density. Below 100°K the density of recombination centers is determined by absorption of 300°K background radiation.