Raman scattering studies of polycrystalline 3C-SiC deposited on SiO2 and AlN thin films

This paper describes the Raman scattering characteristics of the Raman spectra of 0.4- and 2.0-μm-thick polycrystalline (poly) 3C-SiC on AlN /Si and SiO2/Si by using atmosphere pressure chemical vapor deposition (APCVD) with hexamethyldisilane (HMDS) and carrier gases (Ar+H2). In the Raman spectra for all growth temperatures, the D and G peaks of nanocrystalline graphite were measured. The C/Si rate of poly 3C-SiC deposited in (Ar+H2) atmosphere was higher than that in H2 gas, although HMDS C/Si rate is 3. The biaxial stresses of 2.0-μm-thick 3C-SiC on SiO2 and AlN, which was deposited at the growth temperature of 1180 °C after annealing AlN at 800 and 1100 °C, were calculated as 428 and 896 MPa, respectively. Therefore, poly 3C–SiC should admix with nanocrystalline graphite due to the addition of Ar gas and poly 3C-SiC on SiO2 should be better than on AlN for harsh environmental MEMS applications.