Surface properties of silicon oxide films deposited using low-pressure dielectric barrier discharge

The deposition of SiO _X films from low-pressure dielectric barrier discharge plasmas has been investigated using tetraethoxysilane (TEOS)/O ₂ as the feed gas. Films were analyzed using X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), AFM-based nanoindentation/nanowear techniques, and conductive AFM. Film deposition rates and hydrocarbon incorporation in the SiO _X film decrease with addition of O ₂ . High-quality SiO _X films with extremely low surface roughness are deposited at high oxidant concertrations. Addition of oxidant to the feed gas leads to a change in the SiO _X film structure from precursor-like to a dense SiO _X structure. The SiO _X films deposited with TEOS/O ₂ plasmas were found to have soft surface layers, 0.5-1.5 nm thick, which contribute to an improvement of their field emission properties. The effect of gas phase compositions on the surface properties of the conductive surface layer was discussed.