It was noted that the defect evaluation of SiC wafers could be carried out using KOH etching. The method described here involved etching with KOH in the vapor phase rather than in a liquid phase, and this method permitted the reliable etching of both Si- and C-faces. Furthermore, it permitted the delineation of defects on alternate orientation planes of SiC. Polished SiC wafers were etched at 700 to 1000C under atmospheric air pressure. Etch pits were observed on the (00•1), (00• ¯1), (11•0) and (¯11•0) planes. The shapes of the pits were found to be in accord with the crystallographic symmetry. The activation energies for the (00•1) and (11•0) planes were found to be about 17kcal/mol and about
20kcal/mol, respectively. It was demonstrated that the KOH vapor-etching of SiC was simple to implement, and revealed most of the important crystal defects.

A Method for Defect Delineation in Silicon Carbide Using Potassium Hydroxide Vapor. R.T.Bondokov, I.I.Khlebnikov, T.Lashkov, E.Tupitsyn, G.Stratiy, Y.Khlebnikov, T.S.Sudarshan: Japanese Journal of Applied Physics - 1, 2002, 41[12], 7312-6