Formation of nanosized relief on the CdTe single crystals surface by bromine-emerging etchants

Abstract

The chemical-dynamic and chemical–mechanical polishing of the CdTe single crystals surfaces by bromine-emerging etching compositions based on aqueous solutions of K2Cr2O7–HBr–solvent has been investigated. The dependences “solution concentration—polishing rate” have been established and the concentration limits of polishing etching compositions have been determined. The effect of the organic component on the rate and character of their dissolution, the quality of the treatment of the single crystals surfaces has been determined. The dependences of the chemical–mechanical polishing rate on the dilution of the base polishing solution for ethylene glycol and glycerol were found. The surface quality of single crystals after etching in the developed solutions has been investigated using methods of metallographic and profilometric analyzes atomic force and scanning electron microscopy. Using X-ray microanalysis, it was found that after treatment of the semiconductor surfaces by the polishing solutions [Cd]/[Te] ratio was stoichiometric and chromium impurities were absent. The polishing etchants composition and conditions for forming of nanosized relief (Ra < 1 nm) on the CdTe single crystals surface have been optimized.