White-beam synchrotron topographic analysis of muiti-polytype sic device configurations

White-beam synchrotron topographic analysis of SiC device configurations of various polytypes has been carried out. The devices, p-n junctions of area 1 mm², were fabricated via chemical vapour deposition epilayer growth of nominally 3C- or 6H-SiC, on 6H-SÎC substrates grown by either the physical vapour transport or the Lely technique. Detailed analysis of diffracted intensities from the different device areas in grazing reflection geometry, using a specially developed computer program, is presented. Depth profiling carried out using variable penetration depth, grazing-incidence geometries reveals both the polytype configuration and the defect structure as a function of depth in these multi-polytype epilayers.