Relationship between the cell thickness and the optimum period of textured back reflectors in thin-film microcrystalline silicon solar cells

Periodically textured back reflectors with hexagonal dimple arrays are applied to thin-film microcrystalline silicon (mu c-Si:H) solar cells. When the textures have a moderate aspect ratio, the optimum period for obtaining a high short circuit current density (J(SC)) is found to be equal to or slightly larger than the cell thickness. If the cell thickness exceeds the texture period, the cell surface tends to be flattened and texture-induced defects are generated, which constrain the improvement in J(SC). Based on these findings, we have fabricated optimized mu c-Si:H cells achieving a high efficiency exceeding 10% and a J(SC) of 30 mA/cm(2). (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4790642]