Diffusion length measurements in p-HgCdTe using laser beam induced current

The minority carrier diffusion length in p-HgCdTe is a key indicator of mat erial quality and gives an indication of n-on-p diode performance when the zero bias resistance is diffusion limited. We present results of a temperat ure dependent study of diffusion length in p-HgCdTe using laser beam induce d current (LBIC). Carriers are collected by a p-n junction formed using sta ndard diode junction formation conditions, and thus not necessarily extendi ng to the substrate. Two-dimensional modeling is used to examine the validi ty of results obtained using this geometry, as compared to the more standar d diffusion length test structure geometries, which are harder to fabricate . The temperature dependence of the diffusion length can be compared with t heoretical models to determine the dominant recombination mechanisms.