Film Properties of Nanocrystalline 3C–SiC Thin Films Deposited on Glass Substrates by Hot-Wire Chemical Vapor Deposition Using CH4 as a Carbon Source

Abstract

Nanocrystalline cubic silicon carbide (3C–SiC) thin films have been successfully prepared on glass substrates (at a low temperature of around 325 °C) by hot-wire chemical vapor deposition using CH4 as a carbon source. It was found that using CH4, i.e., a SiH4/CH4/H2 system, is useful for the low-temperature deposition of nanocrystalline 3C–SiC thin films and that filament temperature (Tf) is a significant parameter. The structural transition from hydrogenated amorphous SiC (a-SiC:H) to nanocrystalline 3C–SiC occurred with increasing Tf from 1400 to 1600 °C. The mean crystallite size of the obtained films was 2.6 to 8.4 nm. The IR absorption peak due to Si–C bonds showed a single Lorentzian shape, and with increasing Tf, intensity increased and full width at half maximum decreased. This indicates that the crystallinity of 3C–SiC was improved. The SiH4/CH4/H2 system has enabled us to prepare nanocrystalline 3C–SiC thin films at a low H2 dilution ratio in comparison with the findings of other groups obtained thus far, resulting in a high deposition rate of over 0.15 nm/s.