Accurate determination of composition and bonding probabilities in plasma enhanced chemical vapor deposition amorphous silicon oxide

摘要

A method to improve the accuracy in a compositional and microstructural analysis has been applied to the plasma enhanced chemical vapour deposition (PECVD) silicon oxides. Thin layers were deposited on silicon by PECVD under different preparation conditions (power, gas flow ratios, etc.). Annealing at different temperatures were carried out in order to determine their effect on the microstructure. Stoichiometry and hydrogen content were obtained from the infrared absorption bands measured by Fourier transform infrared spectroscopy (FTIR). A correction factor for band areas was calibrated to deconvolve the effect of the multiple internal reflection on infrared spectra. A thermodynamic model was used to determine the bonding probabilities for the different units (H,O,Si, OH) attached to the silicon bonds in a centered tetrahedral.