Deposition and structural properties of silicon carbide thin films for solar cell applications.
The growth of hydrogenated amorphous silicon carbide (a-SiC:H) thin films deposited by Hot- Wire Chemical Vapour Deposition (HWCVD) for solar cell applications has been studied. The films were characterized for structural properties using Fourier Transform Infrared Spectroscopy FTIR, Elastic Recoil Detection Analysis (ERDA), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Raman Spectroscopy (RS). A low temperature of the substrate heater maintained at 280 °C was used in this thesis due to the demand of low-cost solar cells based on cheap substrate that require deposition at such low temperatures. In this thesis, we showed that the structural properties of a-SiC:H films are dependent on the filament temperature and also on the CH4 gas flow rate. It was shown that in non-stoichiometric a-SiC:H, hydrogen content throughout the deposited films varies with depth. An attempt is done in this study to determine, for the first time the absorption strength of the C-Hn bonds in the 950 -1050 cm-1 band of the FTIR spectrum. Real-time ERDA was used to determine the hydrogen kinetics parameters in a single temperature ramp; a model based on the solution of the diffusion equation is used for this effect.