Bilevych Y. Formation of the polished surfaces of single crystals of cadmium telluride and solid solutions based on its in the etching compositions of systems HNO3 - HНal - complexing agents for devices of electronic engineering

The Ph.D. thesis is devoted to research of CdTe, Cd1-xZnxTe and CdxHg1-xTe solid solutions, interaction with solutions of HNO3 - HHal - complexing agent systems and development of etching compositions and modes of surface polishing of the indicated semiconductors. The surfaces of equal etching rates (Gibbs diagrams) of CdTe, Cd1-xZnxTe and CdxHg1-xTe in all investigated etching compositions were obtained using the mathematical planning of experiment, when acetic, lactic, tartaric and citric acid were used as complexing agents, and hydrochloric, hydrobromic and hydroiodic acid were used as HHal. The kinetics behaviours of dissolution were investigated and the limits of polishing and unpolishing solutions in each investigated system were determined. It was determined that addition of indicated complexing agent to the HNO3 - HCl(HBr, HJ) solutions leads to changing both the etching rate and treated surface states. The surface films were investigated using EZMA and XPS techniques and it was shown that thes e films were not uniform and enriched in general by the tellurium oxides. The roughness of the surfaces changes in a range from 0,2 up to 0,1 micron. The influence of chemical processing of a surface on electrophysical parameters of structures Au - p-CdTe is revealed. The compositions of polishing etchants in the investigated systems were optimized and conditions and methods of CdTe, Cd1-xZnxTe and CdxHg1-xTe polishing surfaces preparation were developed.