Amorphous Si Rear Schottky Junction Solar Cell With a LiF/Al Back Electrode

Amorphous Si (a-Si) rear Schottky junction solar cells with a LiF/Al back electrode are proposed as an alternative prototype for high-efficiency thin-film photovoltaics. This device is free from absorption losses occurring at the rear n-type a-Si layer, and thus, overall power conversion efficiency was improved by 13% compared with a conventional p-i-n type solar cell. An ultrathin LiF layer between the absorber and the rear electrode reduces shunt leakage, as well as series resistance; this, in turn, suppresses degradation of the open-circuit voltage and the fill factor while enhancing photocarrier collection in the long-wavelength regime.