Effect of Hydrogen Free Radicals on Hg1−xCdxTe

The effects of atomic hydrogen (H) and Br/methanol etching on Hg1−xCdxTe films were investigated using x-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Exposure of an as-received Hg1−xCdxTe sample to H + H2 resulted in H-induced TeO2 reduction. The oxide reduction was first order with respect to H + H2 exposure. Exposure to H + H2 after etching the Hg1−xCdxTe film in a Br/methanol solution induced Hg and C depletion. Hg and C removal was also observed after completely reducing the TeO2 on the as-received sample. The removal process was hindered by the formation of a Cd-rich overlayer on both etched and unetched surfaces.