Homoepitaxial growth and investigation of stacking faults of 4H-SiC C-face epitaxial layers with a 1° off-angle

We grew epitaxial layers on 4H-SiC C-face substrates with a 1° off-angle, and discussed important factors related to stacking fault (SF) density reduction by investigating the causes of SFs. Three types of SFs were generated, namely 3C inclusions, 8H-SFs and -SFs. The 3C inclusions were caused by 3C-SiC particles, which were present on the substrates before epitaxial growth, or which had fallen onto the substrates during epitaxial growth from the inside walls of a chemical vapor deposition reactor. The 3C-inclusion density decreased when the in-situ H2 etching depth exceeded 0.4 µm because the 3C-SiC particles, which were present on substrates before epitaxial growth, were removed. For 8H-SFs and -SFs, high dislocation density areas on the substrates rather than the dislocations themselves cause these SFs. To reduce the density of these SFs, it is important to suppress generation of the high dislocation density areas on the substrates.