Electron spin resonance spectroscopy of defects in low temperature dielectric films

The electron spin resonance technique has been used for the identification of defects in silicon-based dielectric thin films deposited by plasma enhanced chemical vapor deposition. Characteristics of the signal due to Si dangling bonds are obtained for oxides, nitrides, and oxynitrides deposited below 500°C. The g-values and linewidths are primarily determined by the composition although defect configurations do not obey random bonding statistics in nitrides and oxynitrides. The defect densities depend essentially on the composition, the growth rate, and the substrate temperature. The good correlation with electrical measurements on MIS structures shows that, in the case of silicon nitride, ESR is a powerful technique for the optimization of deposition conditions for films to be used as low temperature gate insulators. © 1988, SPIE.