An iodine-based etching system, H 2 O 2 -HI-citric acid, has been developed and tested on CdTe samples with orientations (111)A, (111)B, (110), and (100). The etching velocity of CdTe was shown to depend on sample orientation and other etching conditions. The surface roughness was comparable with that of the surfaces after Br-methanol treatment. A comparative study of the chemical composition of the (211)B CdZnTe surfaces etched under different conditions was performed. X-ray photoelectron spectroscopy (XPS) measurements showed that all treated surfaces of CdZnTe samples are enriched with Te. The HI-based treatment seems to be more acceptable than the Br-methanol treatment in terms of elimination of Te oxides from the surface, however.

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Iodine-containing polishing etchants were tested on CdTe and Cd 1Àx Zn x Te surfaces with different orientations. The nature of the chemical dissolution of CdTe with (111)A, (111)B, (110), and (100) orientations in the I 2 -methanol solution was studied. It was established that this dissolution is diffusion controlled. Study of the chemical composition and structure of the (211)B Cd 1Àx Zn x Te surfaces etched under different conditions was carried out. X-ray photoelectron spectroscopy (XPS) measurements showed that a stoichiometric surface was achieved after short heating of the etched surface in vacuum. Reflection high-energy electron diffraction (RHEED) measurements reveal a high-quality single-crystalline surface layer in samples etched with iodinemethanol solutions as compared with bromine-methanol treatment.

An iodine-based etching system, H 2 O 2 -HI-tartaric acid, was tested on CdTe samples with (110), (100), (111)A, and (111)B orientations. The etching rate of CdTe was shown to depend on the sample orientation, ratio of etchant composition components, temperature, and rotation speed of the disc. A study of the chemical composition and structure of the (211)B Cd 1Àx Zn x Te surfaces etched under different conditions was carried out. X-ray photoelectron spectroscopy (XPS) measurements showed that a nearly stoichiometric surface was achieved after heating of the etched surface in vacuum. Reflection highenergy electron diffraction (RHEED) measurements revealed a very good single-crystalline surface layer in samples etched with HI-based solutions as compared with bromine-methanol treatment.

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