Small pyramidal textured ultrathin crystalline silicon solar cells with double-layer passivation

Ultrathin crystalline silicon solar cells are a promising technology roadmap to achieve more cost effectiveness. However, experimental reports on ultrathin crystalline silicon cells with thickness less than 20 mu m are rare. Here, we experimentally fabricate and investigate ultrathin monocrystalline silicon solar cells consisting of 16 mu m-silicon base thickness and low-cost front random pyramidal texture with the feature size of 1-2 mu m. The normalized light absorption is calculated to explain the measured external quantum efficiency. The achieved efficiency is 15.1% for the single-layer passivated textured solar cell. In addition, via double-layer passivation of Al2O3/SiNx, the efficiency is further increased to 16.4% for the best textured cell, which significantly improves the absolute efficiency with Delta eta = 1.3%. (C) 2017 Optical Society of America