C-Si Thin-Films on Carbon-related Substrates: Deposition and Photovoltaic Cells

Fabrication of crystalline silicon thin-film solar cells (CSiTFSC's) on foreign substrates (nonsilicon materials) has been studied at various photovoltaic research institutes. The primary motivation behind the use of foreign substrates is to significantly reduce the consumption of solar-grade silicon, and that use may also completely eradicate the need for wafer production by sawing. The impact of foreign substrates as a substitute is significant in terms of savings in comparison to conventional production of silicon-based solar cells in the photovoltaic industry. High temperature crystalline silicon film deposition is favorable for increasing the efficiency of CSiTFSC's on carbon based ceramics substrates. High-temperature processes provide an opportunity to deposit silicon films with larger grain sizes at higher deposition rates. Graphite and silicon-carbide substrates containing elemental carbon have been studied. Thus far, efficiencies in the range of 13.4% for graphite and 15% for silicon-carbide substrates have been demonstrated. A detailed overview of the processes adopted for solar-cell implementation on carbon substrates is addressed in the literature.