Optical properties of silicon oxynitride films grown by plasma-enhanced chemical vapor deposition

In this paper, silicon oxynitride films (SiOxNy) grown by plasma-enhanced chemical vapor deposition are investigated. As precursor gases silane (SiH4), nitrous oxide (N2O), nitrogen (N2) and ammonia (NH3) are used with different compositions. We find that for achieving high nitrogen content adding ammonia to the precursor mix is most efficient. Moreover, we investigate the balance between adsorption and desorption processes during film growth by investigating the film growth rate as a function of the substrate temperature. From these data we are able to determine an effective activation energy for the film growth, corresponding to the difference between adsorption and desorption energy. Finally, we have thoroughly investigated the optical properties of the films using spectroscopic ellipsometry. From these measurements, we suggest a parametrized model for the refractive index and extinction coefficient in a wide range of compositions based on a Cauchy- and a Lorentz-fit.

Automated summary

Silicon oxynitride films grown by plasma-enhanced chemical vapor deposition were investigated, with ammonia found to be the most efficient in achieving high nitrogen content. The balance between adsorption and desorption processes during film growth was studied by examining the growth rate as a function of substrate temperature. Optical properties of the films were thoroughly investigated using spectroscopic ellipsometry, and a parametrized model for the refractive index and extinction coefficient based on Cauchy- and Lorentz-fit was suggested.