Surface defects generated by intrinsic origins on 4H-SiC epitaxial wafers observed by scanning electron microscopy.

Surface defects with intrinsic origins in an epitaxial layer on 4H-SiC wafers were observed by scanning electron microscopy. Commercially available 4H-SiC epitaxial wafers with 4° or 8° off-axis angles from the [0001] direction toward the [112¯0] direction were used in this experiment. Various types of defects, including micropipes, pits, carrots, stacking faults and wide terrace and high step structures, were observed and clearly identified. The defects are presented as a catalog that can be used in the identification of surface defects.