NANO-IMPRINT TECHNOLOGY COMBINED WITH ROUGH TCO MORPHOLOGY AS DOUBLE TEXTURED LIGHT-TRAPPING SUPERSTRATE FOR THIN FILM SOLAR CELLS

Two types of nano-imprinted 2D grating textures were tested on their light trapping performance for thin film Si tandem solar cells in combination with various TCO’s. The combination with rough TCO layers like LPCVD ZnO leads to double textured superstrates that exhibit at least a similar light trapping capability as the state-of-the-art reference while using thinner TCO layers. Further optimization in combination with nano-imprinted AR textures on the air/glass interface has the potential for >13% devices with thin TCO and absorber layers.