Investigating MBE MCT layers by using scanning laser microscopy

By using scanning laser microscopy (SLM) technique, spatial distribution electrically active areas in MBE grown Hg_1-xCd_xTe (MCT) layers with composition x=0,22 and x=0,3 as well as in MCT based planar photodiode arrays was explored. Correlation between the result of SLM studies of the fragment of the planar photodiodes array and their current-voltage dependencies were discovered. Spatial distribution of the electrical nonuniformities in the volume of MCT epitaxial film was discovered by using step-by-step etching. The comparison SLM images of the fragment of MBE grown MCT layer to profiles of the spatial distribution of the background impurities (C, Cu, As, Li) concentration, found by using secondary ion mass-spectroscopy (SIMS) technique, allows to speak about correlation of the spatial distribution of the electrical nonuniformities with spatial distribution of the background impurities.