Morphological defects and uniformity issues of 4H-SiC homoepitaxial layers grown on off-oriented (0Â Â 0Â 0Â 1) Si faces

The morphological defects and uniformity of 4H-SiC epilayers grown by hot wall CVD at 1500 °C on off-oriented (0 0 0 1) Si faces are characterized by atomic force microscope, Nomarski optical microscopy, and Micro-Raman spectroscopy. Typical morphological defects including triangular defects, wavy steps, round pits, and groove defects are observed in mirror-like SiC epilayers. The preparation of the substrate surface is necessary for the growth of high-quality 4H-SiC epitaxial layers with low-surface defect density under optimized growth conditions.