Nano-mirror embedded back reflector layer (BRL) for advanced light management in thin silicon solar cells

摘要： This work illustrates a technology for advanced light management by introducing a nonconventional back reflector layer (BRL) in amorphous silicon (a-Si:H) solar cells. To meet this, silver sulfide (Ag2S) nanoparticles with ~50 nm diameter have been chosen as the nano-mirror owing to its low parasitic absorption loss over a broad wavelength (300 to 1100 nm) region. The Ag2S NPs were sandwiched between two indium tin oxide (ITO) layer and placed as the back reflector layer of an a-Si:H solar cell to achieve better light trapping within the active layers. The embedded structure exhibited high reflectance (up to 93%) in the red and near-infrared region, the main working zone of a-Si:H cells. With the incorporation of such state of the art back reflector structure in a-Si:H solar cells, a photo-conversion efficiency of 10.58% has been achieved; which is one of the best in this class.