Study of 3C-SiC nucleation on (0 0 0 1) 6H-SiC nominal surfaces by the CF-PVT method

3C-SiC nucleation on (0 0 0 1) 6H-SiC nominal surfaces was investigated during the heating-up step of the continuous feed-physical vapour transport (CF-PVT) growth technique. We focused on the heteropolytypic 6H-3C transition under silicon-rich gas phase for temperatures from 1800 to 2000 °C. Seed polarity effects were studied. The 3C proportion reached a maximum for a well-defined temperature which was higher on the C face than on the Si face. The 2D nucleation threshold for the 3C polytype was around 1825 °C on the Si face. 3C formation was closely connected to the surface morphology, i.e. to the development of facets (on-axis regions) on the Si face.