Homoepitaxial Growth on Si-Face (0001) On-Axis 4H-SiC Substrates

摘要

Homoepitaxial growths of 4H-SiC were performed on Si-face (0001) on-axis substrates in a SiH_(4)-C_(2)H_(4)-H_(2)-HCl system by using our home-made vertical hot wall CVD reactor. The influence mechanism of the growth temperature and C/Si ratio on the morphology and growth rate was studied. It is found that the steps in the epilayer become more clear with the increasing temperatures. The result indicates that the C/Si ratio window of on-axis epitaxial growth is very narrow. Only when the C/Si ratio was 1.2, a slightly improved surface morphology can be achieved. The results indicate that 4H-SiC epitaxial layers were obtained on on-axis substrates and the films were highly-oriented 4H-SiC.