Hydrogenated Amorphous Silicon Nitride Thin Film as ARC for Solar Cell Applications

Hydrogenated amorphous silicon nitride (a-SiN_x:H) thin films have been deposited using Silane (SiH₄) and Nitrogen (N₂) as source gases by Plasma Enhanced Chemical Vapour Deposition (PECVD). During deposition, Silane flow rate is kept constant at 2 sccm and Nitrogen flow rate is varied from 800 to1200 sccm. Fourier transform Infrared spectroscopy (FTIR) analysis is carried out to identify all the possible modes of vibrations such as Si-N, Si-H and N-H present in the films and the effect of nitrogen flow on these parameters is correlated. The refractive index of the a-SiN_x:H films is calculated using UV-VIS spectroscopy measurements by Swanepoel’s method and optical bandgap is calculated using Tauc’s equation.