Photovoltaic applications of hydrogenated amorphous silicon thin films grown by the Saddle Field Glow Discharge Method

Thin film hydrogenated amorphous silicon (a-Si:H) is widely used for photovoltaic solar cells. We present a combined theoretical and experimental study of the thin a-Si:H films for efficient and inexpensive solar cells, grown by the Saddle Field Glow Discharge Method. The type of solar cell studied is glass/SnO$_{2}$/p-i-n Si:H/Al. We investigated the mechanism of hydrogen diffusion inside the film, its relation to the bonding within the amorphous silicon network. Hydrogen diffusion in a-Si:H was modeled using first-principles finite temperature molecular dynamics. Optimization of the solar cells was performed based on the experimental diffusion coefficients, carrier mobilities, parameters of the p-i-n structures, and electron band structure (defect distribution inside the gap). An analytical model to optimize photo-conversion efficiency of a-Si:H based solar cells with contact grid has been developed. The research was supported by the Centre for Materials and Manufacturing/Ontario Centres of Excellence (OCE/CMM) ``Sonus/PV Photovoltaic Highway Traffic Noise Barrier'' project.