N2 decomposition by hot wire and N2 post-deposition treatment on hydrogenated microcrystalline silicon thin films

Post-deposition treatment of hydrogenated microcrystalline silicon (µc-Si:H) was carried out using a hot wire in atmospheres of N2, N2/H2 or H2 and the states of the bonds in the µc-Si:H films were investigated using X-ray photoelectron spectroscopy. For the µc-Si:H film treated in N2 at the filament temperature (Tf) of 1600 °C, a weak N1s peak was observed. It increased slightly with increasing Tf from 1600 to 1900 °C and increased dramatically with increasing Tf from 1900 to 2000 °C. The N1s peak of the µc-Si:H film treated in N2/H2 at Tf = 2000  °C was one order of magnitude lower than that in N2 at Tf = 2000 °C. These findings indicate that N2 molecules decompose on the heated filament and that the addition of H2 prevents N2 decomposition.