CHEMOMECHANICAL POLISHING OF GALLIUM-ARSENIDE AND CADMIUM TELLURIDE TO SUBNANOMETER SURFACE FINISH - EVALUATION OF THE ACTION AND EFFECTIVENESS OF HYDROGEN-PEROXIDE, SODIUM-HYPOCHLORITE AND DIBROMINE AS REAGENTS

Aqueous hydrogen peroxide and sodium hypochlorite in the pH range 7-9 are more effective chemomechanical polishing reagents for gallium arse nide than is dibromine in methanol. Sodium hypochlorite is an acceptab le alternative to hydrogen peroxide for gallium arsenide: it also prod uces good-quality surface finishes on cadmium telluride over the same pH range. The results of dip-etch and polishing reactions, studied usi ng [Br-82]-labelled dibromine, atomic absorption spectroscopy (AAS) an d pH or concentration variation, are used to propose a model for chemo mechanical polishing of these materials.