Fast epitaxial growth of high-purity 4H-SiC($000\bar 1$) in a vertical hot-wall chemical vapor deposition) in a vertical hot-wall chemical vapor deposition

Abstract

4H-SiC($000\bar 1$) epitaxial layers with a 14–28-µm thickness have been grown at high growth rates of 14–19 µm/h by chimney-type, vertical hot-wall, chemical vapor deposition (CVD) at 1,750°C. The 3C hillocks are formed on the epilayers grown under relatively low C/Si ratios. When grown at a relatively higher C/Si ratio of 0.6, the hillock density has been decreased to 1 cm⁻². Under the C-rich condition, the concentrations of residual impurity (nitrogen) and intrinsic defects (Z_1/2 and EH_6/7) have been reduced. When growth has been performed at low C/Si ratios of 0.4 and 0.5, all the micropipes in the substrates (more than 100 micropipes for each condition) have been closed during CVD growth.