Preparation of SiNx film by pulsed laser ablation in nitrogen gas ambient

Silicon nitride films were synthesized by reactive pulsed laser ablation (PLA) of a Si target in N2 gas atmosphere. At different laser fluences and N2 gas pressures the infrared absorption peak attributed to Si–N bond was evaluated. The nitrogen concentration in the film increased with the increasing fluence. Nitrogen concentration depended also on N2 gas pressure; it increased as N2 pressure increase up to 10 Pa and then it decreased with further increasing N2 gas pressure. These results indicate that decomposition of N2 molecules and collisions of SiNx clusters with N2 molecules are essential to prepare silicon nitride films by PLA method. The PLA is a promising method to fabricate nitrogen rich silicon nitride films without using poisonous gases such as silane and ammonia.