Temperature-Dependent Photoconductivity of n-InSe Single Crystals

Abstract

The photoconductivity and electrical transport parameters of indium monoselenide single crystals have been measured as functions of temperature in the range 77–300 K. The results demonstrate that, below 240–250 K, not only the dark electrical conductivity and free carrier mobility but also the key photoconductivity parameters of the semiconductor vary from sample to sample. With decreasing dark electrical conductivity, the temperature-dependent photoconductivity of the crystals begins to exhibit behavior atypical of ordered crystalline semiconductors. Such behavior is shown to be due to the fact that the n-InSe single crystals contain random macroscopic (large-scale) defects identical in phase composition and crystal structure to the major material.