Bromine-Methanol Etching of Cadmium Telluride in a Rotating Disk Reactor

Abstract

ABSTRACTThe kinetics of the bromine-methanol etching of CdTe were studied in a rotating disk reactor as a function of temperature, bromine concentration, substrate orientation, and rotation rate. The results indicated that the etching process is mass transfer controlled from -20°C to 40°C and to a maximum rotation rate of 1200 RPM. A one-dimensional transport model was used to obtain effective diffusion coefficients for bromine in methanol. The diffusion coefficient of the etchant in methanol is given by 3.7×10-8 (T/η) cm2/s over the range of 2.5°C to 23°C.