Deposition temperature effect on a-Si:H produced by DC magnetron sputtering

The use of hydrogenated amorphous silicon, a-Si:H, for improving heterojunction solar cell efficiency and decreasing cost has found increasing interest in recent years. Hydrogen incorporation in thin films of amorphous silicon is crucial for obtaining high quality semiconductor because it passivates Si dangling bonds in the structure. In the present work the effect of deposition temperature in the hydrogen incorporation in a-Si:H films growth by DC magnetron sputtering in Ar-H plasma was studied. The films were deposited over glass and Silicon wafer substrates, and characterized by Raman, FTIR and UV-Vis techniques. The results showed that deposition temperature of 200°C gave an amorphous film with the highest level of hydrogenation about of 28%. The relatively high band gap, between 1,70 and 1.9 eV, is consistent with the significant presence of hydrogen in the amorphous silicon film.