EFFECT OF THE DISLOCATION DENSITY ON MINORITY-CARRIER LIFETIME IN MOLECULAR-BEAM EPITAXIAL HGCDTE

The photoconductive minority-carrier lifetime has been measured as a function of temperature and etch-pit density in n-type HgCdTe grown by molecular beam epitaxy with a composition range x = 0.22-0.23 to determine the limiting recombination mechanisms, particularly those related to dislocation density. In the extrinsic region at temperatures T < 77 K, the minority-carrier lifetime is limited by Shockley-Read recombination. Strong correlation between minority-carrier lifetime and dislocation density is observed.