Bonding rearrangement in amorphous silicon nitrides deposited by hot-wire chemical vapor deposition upon thermal annealing

The bonding rearrangement upon thermal annealing of amorphous silicon nitride (a-SiNx:H) films deposited by hot-wire chemical vapor deposition was studied. A wide range of N/Si atom ratio between 0.5 and 1.6 was obtained for the a-SiNx:H sample series by varying the source gases ratio only. Evolutions of Si–N, Si–H and N–H bonds upon annealing were found to depend strongly on the N/Si atom ratio of the films. According to the above observations, we propose possible reaction pathways for bonding rearrangement in a-SiNx:H with different N/Si ratios.