To reduce the defect density inherent in conventional heteroepitaxial growth of SiC on Si, selective epitaxy followed by lateral epitaxial growth was performed in a conventional atmospheric pressure chemical vapor deposition (APCVD) system. The source gas was primarily hexamethyldisilane (HMDS). Hydrogen was used as the carrier gas and small amounts of hydrogen chloride (HC1) were added to improve the selectivity. Si(001) wafers, with an oxide layer (~ 700 nm thick) as a mask, were used as substrates. The grown films were analyzed using optical microscopy and scanning electron microscopy (SEM). In earlier work, we had demonstrated the problems associated with the application of this technique - viz., oxide degradation and high growth temperature. Using HMDS, the growth temperature has been considerably reduced allowing the continued use of an oxide mask. Selective growth was demonstrated in films grown at 1250°C and below.
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