Large-scale, high-efficiency thin-film silicon solar cells fabricated by short-pulsed plasma CVD method

A novel growth technology of microcrystalline silicon (μμc-Si:H) thin films has been developed using short-pulsed VHF plasma CVD method [K. Nomoto, et al., Short-pulse VHF plasma-enhanced CVD of high-deposition-rate a-Si:H films, in: Proceedings of the 14th European Photovoltaic Solar Energy Conference and Exhibition, 1997, pp. 1226–1230]. The homogeneity of crystallinity in a film over square meter was improved by using this technology. We applied this technology to intrinsic layers of μμc-Si:H single solar cell, and confirmed that the homogeneity of cell's characteristics on a large-scale substrate was improved. And using this novel fabrication technology to intrinsic layers of a-Si:H/μμc-Si:H tandem thin-film Si solar cell, initial conversion efficiency of 12.1%, corresponding to about 11% stabilized conversion efficiency was obtained with a large-scale substrate size of 925mm×560mm.