Characterization of (Hg,Cd)Te by the photoconductive decay technique

Abstract
A spatially resolved characterization technique is described that can separate surface and bulk (Hg,Cd)Te material parameters. Photoconductive (PC) decay and metal–insulator semiconductor (MIS) measurements were used to characterize n-type (Hg,Cd)Te (x=0.22) material and the anodic oxide–(Hg,Cd)Te interface. By analysis of the transient PC decay waveform, the surface recombination velocity and minority carrier lifetime were determined and then correlated to (Hg,Cd)Te material parameters. These results have been used to obtain estimates of the average bulk Shockley–Read density and surface state density.