Combined structural and optical studies of stacking faults in 4H‐SiC layers grown by chemical vapour deposition

Abstract

AbstractThe formation of in‐grown stacking faults (SFs) in chemical vapour deposition (CVD) grown 4H‐SiC epilayer has been studied by high‐resolution transmission electron microscopy (HRTEM) and low‐temperature photoluminescence (LTPL). Local inhomogeneities in the SF density have been found, where different SF arrangements appear. They range from pure 8H‐SiC unit cells to a few distinguished sequences, forming in some cases long‐range semi‐periodic incommensurate structures. Despite such large dispersion, the same optical (LTPL) signature is always found. This is discussed in the light of coupled quantum well models.magnified imageHRTEM image showing the formation of an extended defect (16 bilayers thick) in a CVD grown 4H‐SiC epitaxial layer.