A review was presented of the various optical techniques that could be used to investigate the presence of as-grown and/or process-induced stacking faults in 4H–SiC epitaxial layers. A stacking fault was always a finite admixture of different polytypes, and the review began with a brief review of the systematics of SiC polytype structure and electronic properties. Next, the optical signature was considered and was compared with the results of several model calculations; successively taking account of the effects of valence band offset, internal polarization and non-homogeneity of the potential well. Finally, cathodoluminescence and micro-photoluminescence techniques were considered and it was shown that, in both cases, some screening of the built-in electric field could be achieved.

Optical Investigation Methods for SiC Device Development - Application to Stacking Faults Diagnostic in Active Epitaxial Layers. J.Camassel, S.Juillaguet: Journal of Physics D, 2007, 40, 6264-77