Gas flow effects on the structure and composition of SiNx/Si/SiNx films prepared by radio-frequency magnetron sputtering

The structure and composition of SiNx/Si/SiNx films were investigated by means of x-ray reflectivity, x-ray photoelectron spectroscopy, and atomic force microscopy. The three-layer films were prepared by radio-frequency magnetron sputtering under the condition of constant nitrogen flow and the argon flow. It was found that the deposition rate and surface structure of the silicon nitride films were mainly determined by the nitrogen flow rather than the argon flow. But the composition of the silicon nitride films was controlled by the gas flow ratio (F-Ar/F-N2) used during sputtering.