Growth of silicon carbide epitaxial layers on 150-mm-diameter wafers using a horizontal hot-wall chemical vapor deposition

Epitaxial layers on a 150-mm-diameter silicon carbide wafer have been grown using a horizontal hot-wall chemical vapor deposition system for three 150-mm-diameter wafers. We investigated the surface morphology and surface defects such as shallow pits and triangular defects of the grown epitaxial layers, as well as the thickness and carrier concentration uniformities. The shallow pit and triangular defect densities were 4.6 cm−2 and 1.6 cm−2, respectively, and the thickness and the carrier concentration uniformities were 3.9% and 47%, respectively. We focused on improving the carrier concentration distribution for practical use and concluded that the cause of the distribution was the distribution in the effective C/Si ratio in the direction of the gas flow.