SiO2 as oxygen source for the chemical vapor transport of SiC

The potential of oxygen as a transporting agent for the growth of SiC epitaxial layers was studied by a thermodynamic simulation coupled with experiments in a sublimation like reactor. The calculations show that SiO and CO gaseous species are the main transporting species and they both form on a wide range of temperature. Simulation of a thermal gradient reveals that SiC transport is possible for temperatures higher than 1950 K. Experiments performed with silica powder as a source of oxygen mixed with SiC powder confirm the possibility to grow SiC layers at higher pressure than the sublimation technique. Moreover, the addition of silica was found to be interesting to suppress the graphitisation of the SiC source.