Optimization of SiN_x:H films deposited by PECVD for reliability of electronic, microsystems and optical applications

摘要

This paper presents the correlation between the optical properties and the chemical and electrical properties of amorphous silicon nitride (SiN_x:H) films prepared by reactor Plasma-Enhanced Chemical Vapor Deposition (PECVD). The effects of temperature and mixture of gases (NH_3/SiH_4/N_2) on these dielectric films are investigated in this study. Silane (SiH_4) and ammonia (NH_3) are used as the reactive species, while nitrogen (N_2) is used as a dilution gas. A particular focus is made on the improvement of the electrical properties that are strongly correlated to the physicochemical bonds films properties. The incorporation of the N_2 dilution leads to the deposition rate and hydrogen content reductions in the film. An optimal gases mixture with N_2 is obtained to improve the breakdown voltage at low temperature, 200 ℃. Fundamental properties of these fabricated films are characterized by their elemental composition, chemical specification, residual stress, optical and electrical properties. The results experimentally show that this film can be used to improve some of the key deposition parameters for the reliability of semiconductor, microsystems and optical applications.