Fast homoepitaxial growth of 4H-SiC with low basal-plane dislocation density and low trap concentration by hot-wall chemical vapor deposition

Fast homoepitaxial growth of 4H-SiC has been carried out on 8° off-axis (0 0 0 1)Si substrates by horizontal hot-wall chemical vapor deposition (CVD) at 1650 °C. Growth at low pressure, by which gas-phase Si condensation can be minimized, has made it possible to obtain mirror-like surface at high growth rate up to 50 μm/h. Epilayers grown on chemical mechanically polished (CMP) substrates show much better surface morphology than those on as-received substrates. The basal-plane dislocation (BPD) density can be decreased by fast epitaxy on CMP substrates, and the minimum BPD density obtained in this study is 22 cm−2. The concentration of Z1/2 and EH6/7 centers is in the low 1012 cm−3 range even at high growth rate of 50 μm/h. In photoluminescence (PL), free exciton peaks are remarkably dominant, and impurity-related peaks and L1 peak are hardly observed.