Optoelectronic and structural properties of good quality hydrogenated amorphous silicon carbide films deposited by hot wire assisted RF plasma deposition technique

Hydrogenated amorphous silicon carbide (a-SiC:H) films were deposited by using a combination of radio frequency plasma enhanced chemical vapour deposition (RF-PECVD) and heated filament techniques with the objective of improving the quality of the films due to the possible beneficial effect of the latter technique. The atomic hydrogen produced via electron (emitted from the filament) impact dissociation of the process gases plays a significant role in improving the properties of the film such as the structure and bonding configuration. The electrons emitted from the hot filament also help in dissociation of methane molecules into different types of radicals. From the characterization of the films thus produced it is seen that by the combination of the two methods of deposition under optimised condition carbon is incorporated more as a Si-C bond which is structurally better. These results in better opto-electronic properties at high band gap of a-SiC:H which also shows lower light induced degradation than those of the films produced by only using the RF PECVD method.