Photoemission studies of a-SixC1−x:H/a-Si and a-SixC1−x:H/ hydrogenated amorphous silicon heterojunctions

The interfaces between hydrogenated amorphous silicon-carbon alloy and amorphous silicon, both hydrogenated and not, were investigated by photoemission spectroscopy. It is found that the valence-band discontinuity is 0.15±0.1 eV for the amorphous Si case and zero within the experimental uncertainty for the hydrogenated amorphous Si. The relevance of this result for understanding the behavior of the p-i-n amorphous solar cells is discussed.