N2 post-deposition treatment on silicon thin films with a hot-wire chemical vapor method at a low wire temperature

For nitride layer formation on a hydrogenated microcrystalline silicon film surface, post-deposition treatments were carried out using a tungsten wire heated to 1700 deg. C in N2 (12 Torr) or N2/H2 (4 Torr) atmospheres. The nitride layers were investigated with an X-ray photoelectron spectroscopy. The intense peaks due to the Si-N bonds were observed. Those in N2 treatment were larger with increasing the treating time and decreased with depth direction, while those in N2/H2 treatment were virtually unchanged with the treating time and the depth up to about 20 nm. These findings indicate that even at a low wire temperature of 1700 deg. C, N2 molecules decompose sufficiently and nitride layers can be formed when high gas pressures are used.