Defects analysis in single crystalline 6H-SiC at different PVT growth stages

摘要: 6H-SiC single crystal was grown by the physical vapor transport (PVT) method. The cut into several (0001) wafers and two of were selected for analysis: wafer close to surface boule (wafer A), substrate B). characterized a double X-ray diffraction rocking curve. curve A shows symmetrical peak with full widths at half maximum (FWHM) 40 arcsec, while that B split peaks, which indicate existence subgrains. Defects, such as dislocations, micropipes, subgrains etc., in studied KOH etching combined optical micrography topography. Possible relationships between observed defects their formation mechanisms growth process are discussed.