Crystal growth of micropipe free 4H-SiC on 4H-SiC {0 3 3̄ 8} seed and high-purity semi-insulating 6H-SiC

Abstract Micropipe free c-plane 4H–SiC wafers were achieved by sublimation growth on the 4H–SiC { 0 3 3 ¯ 8 } seed. 4H–SiC { 0 3 3 ¯ 8 } seeds were obtained by inclining the c -plane to 〈 0 1 1 ¯ 0 〉 at 54.7°. A transmission X-ray topograph of the micropipe free c -plane wafer revealed that there were no macroscopic defects with lattice displacements. Crystal growth of undoped (vanadium-free) semi-insulating 6H–SiC was carried out by our sublimation system. In order to achieve high resistivity, high-purity SiC source and controlled instruments were used for the reduction of nitrogen, boron and metal impurity backgrounds. Hence high-purity and high-resistivity 6H–SiC 2 and 3 in in diameter were developed for high-frequency power transistors.