Surface characterization and properties of silicon nitride films prepared by ion-assisted deposition

Silicon nitride (SiN) films had been prepared at low substrate temperature (100 °C) using the ion-assisted deposition (IAD) process. The films had been analyzed by the measurement of X-ray diffraction, atomic force microscopy, Fourier transform infrared spectrometry, nano indenter, and ellipsometry. The effects of N-ion current density on the surface morphology, compositional, mechanical, and infrared optical properties of SiN thin films were investigated. The results showed that the stoichiometric Si₃N₄ thin film with desirable properties, such as continuous and smooth surface morphology, extremely low hydrogen content, mechanical strong, and low extinction coefficient, could be obtained by using the IAD technique.