Effects of C/Si ratio in fast epitaxial growth of 4H-SiC(0Â 0Â 0Â 1) by vertical hot-wall chemical vapor deposition

The C/Si ratio dependence of growth rate, surface morphology, micropipe closing ratio, doping concentration and deep-level concentration have been investigated in fast epitaxial growth of 4H-SiC (0 0 0 1) epilayers by chemical vapor deposition in a vertical hot-wall reactor. The doping, Z1/2 and EH6/7 centers concentrations of thick epilayers decrease with increasing C/Si ratio of source gases. By adjusting the C/Si ratio at 0.7, specular surface morphology with a low doping concentration of 1×1013 cm−3 has been obtained at a growth rate of 33 μm/h, and the concentrations of Z1/2 and EH6/7 centers have been kept low, 8×1012 and 4×1012 cm−3, respectively.