Film samples were deposited by means of the electron cyclotron resonance plasma method at room temperature, by using SiH4 and O2 as precursor gases. The film composition was measured by means of heavy-ion elastic recoil detection analysis and energy-dispersive X-ray spectroscopy. Sub-oxide films with compositions ranging from SiO2 to SiH0.38 were obtained. Infra-red spectroscopy revealed the presence of various Si–O and Si–H vibration modes. The off-stoichiometric films also exhibited a broader Si–O–Si stretching peak than did stoichiometric ones; thus indicating higher bonding disorder. The positions of the Si–O–Si bending and rocking modes did not depend upon the film composition. The peak positions of the Si–H modes were strongly dependent upon the Si environment. Electron spin resonance measurements showed that stoichiometric films contained the well-known E’ center (·SiO3) at concentrations of 1016 to 1017/cm3. In Si-rich films (x much smaller than unity), the Si dangling bond center (SiDB, ·SiSi3) was the only detectable defect; with concentrations of 1018 to 1019/cm3. Both E’ and SiDB centers were found in near-stoichiometric films.

Bonding Configuration and Density of Defects of SiOxHy Thin Films Deposited by the Electron Cyclotron Resonance Plasma Method. E.San Andrés, A.del Prado, I.Mártil, G.González-Díaz, D.Bravo, F.J.López, M.Fernández, W.Bohne, J.Röhrich, B.Selle, I.Sieber: Journal of Applied Physics, 2003, 94[12], 7462-9