Raman determination of stresses and strains in 3C-SiC films grown on 6-inch Si substrates

We demonstrate Raman spectroscopy determination of stresses and strains as a function of distance from the growth interface in a 2.2 mu m thick 3C-SiC film grown on a 6-inch Si substrate using low-pressure chemical vapor deposition. The Raman measurements have been performed with the back-scattering geometry on the SiC film that has been reactive ion etched to various thicknesses (0.44 - 2.2 mu m). The values of the stress and strain determined as a function of the distance from the interface show maximum at the interface, decrease rapidly between 0 and 0.7 mu m, and become constant between 0.7 and 2.2 mu m. We believe this is a clear evidence for relaxation of stress and strain at the first 0.7 mu m growth of SiC films on Si.