Chemical-vapor-deposition growth and characterization of epitaxial 3C-SiC films on SOI substrates with thin silicon top layers

Epitaxial 3C-SiC films were grown by chemical vapor deposition on the silic on-on-insulator (SOI) substrates with 20-75-nm-thick Si top layers. A relat ively low growth temperature of 1150 degreesC and a reduced hydrogen flow r ate of 1 lpm during the precarbonization process was necessary to preserve the SOI structure and thereby obtain high-quality SiC films. The transmissi on electron microscopy observation of the SiC/SOI structures revealed high density of misfit dislocations in the SiC film, but no dislocation within t he top Si layer. The x-ray-diffraction results did not show any significant shift of the (400) SiC peak position among the SiC/Si and the SiC/SOI samp les. This strongly suggests that the Si top layer is not deformed during th e SiC/SOI growth and the strain within the 3C-SiC layer is not critically a ffected by substituting the Si substrate with the SOI substrate, even when the Si top layer is as thin as 20 nm.