Single Etch-Pit Shape on Off-Angled 4H-SiC(0001) Si-Face Formed by Chlorine Trifluoride

The etch pit shape of an off-angled 4H-SiC Si-face formed by chlorine trifluoride (ClF 3 ) in nitrogen (N 2 ) ambient has been studied. One type of etch pit with a crooked hexagonal shape was formed at an etching temperature below 500 °C. The angle of the etch pit measured from a cross-sectional atomic force microscopy image was about 10° from the [11 0] view. The dislocation type of the etch pit was discussed in relation to the etch pit shape and an electron-beam-induced current image.