A novel approach for the synthesis of 6H-SiC at a low temperature of 460°C

Silicon carbide single crystals (6H-SiC) have been successfully grown at a temperature as low as 460 degrees C in a supercritical carbon dioxidemolten sodium system starting from dry ice and silicon powder. The crystals with typical size of 220 mu m can be viewed by naked eyes. They were characterized by Raman spectrum, X-ray power diffraction, and Optical microscopy. A blue-green photoluminescence band, centered at 531.1 nm, was observed in the as-grown crystals. The possible formation mechanism of silicon carbide in this system was tentatively discussed. (c) 2006 Elsevier B.V All rights reserved.