Performance of superstrate multijunction amorphous silicon-based solar cells using optical layers for current management

The performance of multijunction amorphous silicon-based thin film solar cells has been reported using thin layers of TiO 2 and SiO x acting as refractive index matching optical layers for different interfaces of the superstrate device structure. Improvement of short-circuit current from the sub-cells of a-Si/μc-Si cells is demonstrated with TiO 2 as anti-reflection layer at TCO/Si interface and SiO x as intermediate-reflector layer between two sub-cells. An initial efficiency of 11.8% is achieved by applying both the TiO 2 and SiO x optical layers in a-Si/μc-Si solar cell.