It was pointed out that the misfit between GaN and 6H-SiC was 3.5%, rather than the 16% in the case of growth on sapphire. Also, that between AlN and 6H-SiC was only 1%. Therefore, use of an AlN buffer was expected to improve the quality of GaN. The early stages of coalescence of GaN on AlN were analyzed in order to identify which dislocations tended to bend. The deposited islands were always limited by {10•0} facets. From the centres of these islands, more than 99% of dislocations bent to the basal plane. The a-type dislocations were found to veer many times from the basal to the prismatic planes. When a+c dislocations bent to the basal plane, they were not seen to return to a prismatic one.

A TEM Evaluation of ELOG GaN Grown on AlN Buffer layer by HVPE on (00•1) 6H-SiC P.Ruterana, B.Beaumont, P.Gibart, Y.Melnik: Proceedings of the SPIE, 1999, 3768, 472-80