Key Points in the Latest Developments of High-Efficiency Thin-Film Silicon Solar Cells

Thin-film silicon has been intensively used in photovoltaic applications. In recent years, most of the record efficiencies in thin-film silicon solar cells have been updated frequently, particularly in microcrystalline silicon solar cells. In this article, key points in the latest developments of high-efficiency thin-film silicon solar cells are reviewed with a short overview of thin-film silicon technology. The main driver for the efficiency improvement of microcrystalline silicon cells was the development of sophisticated light scattering substrates. The well-designed honeycomb-textured substrates enabled a systematic and detailed optimization to realize the growth of high-quality films and significant light absorption enhancement simultaneously. The knowledge obtained about microcrystalline silicon solar cells and the insights regarding light-induced degradation of a-Si:H solar cells were successfully transferred to triple junction cells, which was demonstrated by the achievement of the record stabilized efficiency of 14%.