The electron spin resonance spectra of plasma-deposited amorphous films were investigated as a function of x. When x was less that 1.5, a broad resonance line (around g = 2.005) dominated the electron spin resonance spectra. When x was greater than 1.5, several narrow lines became more pronounced than the broad line. These narrow lines were attributed to Si dangling bond centers with •SiSi2O, •SiSiO2 and •SiO3 configurations. The anisotropic g-factors for the •SiSi2O and •SiSiO2 centers were determined experimentally by means of a curve-fitting analysis. The g-factors were also estimated on the basis of molecular orbital calculations, and the values were found to agree qualitatively with experimental ones. It was suggested that broadening of the electron spin resonance line was reduced by the presence of an O atom at the nearest-neighbor site of the trivalent silicon atom.

T.Inokumo, L.He, Y.Kurata, S.Hasegawa: Journal of the Electrochemical Society, 1995, 142[7], 2346-51