Silicon oxynitride from microwave plasma: fabrication and characterization

Plasma silicon nitride (P-SiN), oxynitride (P-SiON), and silicon dioxide (P-SiO2) films have been prepared from SiH4–NH3–N2O mixtures in a large volume microwave plasma (LMPR, 2.45 GHz) apparatus at TS = 280 °C. Film compositions, determined by X-ray photoelectron spectroscopy and nuclear elastic recoil detection analysis, reveal about 15 at.% hydrogen in P-SiN, <2% in P-SiO2, and intermediate values in P-SiON. Various physicochemical and electrical properties (density, refractive index, intrinsic stress, permittivity, and conductivity) vary systematically with film composition, O/(O + N), determined from the above analyses. The present microwave plasma enhanced chemical vapour deposition (PECVD) films compare favorably with the best PECVD and low pressure chemical vapour deposition (LPCVD) materials reported in the literature.