Evaluation of critical supersaturation ratios during epitaxial growth of hexagonal SiC {0001} under carbon- and hydrogen-rich conditions

Abstract

Critical supersaturation ratios αcrit during epitaxial growth on 6H-SiC (0001) and (000-1) under carbon- and hydrogen-rich conditions were formerly estimated by assuming disc-shaped critical nuclei whose side surfaces were terminated with silicon and carbon atoms, respectively. Since this assumption contradicts the atomic configurations of possible hexagonal-prism-shaped critical nuclei, we evaluated αcrit by using the reported surface free energies for hydrogen-passivated 3C-SiC surfaces. To account for the observed αcrit being much larger on 6H-SiC (0001) than on 6H-SiC (000-1), we considered that silicon atoms on the side surfaces of hexagonal-prism-shaped critical nuclei be terminated not by carbon but by hydrogen atoms.

Influence of Carbon Source on the Buffer Layer for 4H-SiC Homoepitaxial Growth

“…As growth pressure increases, the surface rms value initially enlarges and then reduces, while surface defect density decreases and subsequently increases. Optimal conditions, with lower surface rms and defect density, are observed at a growth pressure of 70 Torr, where the epitaxial wafers exhibit the highest quality [31][32][33]. Figure 15 illustrates how the surface rms and surface defect density of the epi layer vary under different growth pressures.…”