Transparent Wox Window Layers For Silicon Based Heterojunction Solar Cells

The fabrication of window layers more transparent than those based on amorphous silicon (a-Si:H) could be a key factor to enhance the efficiency of heterojunction (111) solar cells. In this work amorphous hydrogenated silicon oxide (a-SiOx:H) as a transparent passivating layer and substoichiometric tungsten oxide (WOx), with its wide band gap and high work function, are proposed to form efficient hole-selective contacts on silicon-based HJ solar cells. A comparison is made between WOx, films grown by RF sputtering and by thermal evaporation.