²⁹Si hyperfine spectra and structure of E' dangling-bond defects in plasma-enhanced chemical-vapor deposited silicon dioxide films on silicon

We report the observation of ²⁹Si hyperfine spectra in a thin silicon dioxide film. The hyperfine observations allow us to establish with virtually absolute certainty that E' centers reported earlier in plasma-enhanced chemical-vapor deposited oxides are silicon atoms bonded to three oxygen atoms with an unpaired electron residing in an sp hybridized orbital on the silicon. The hyperfine spectra additionally provide us with information regarding silicon bond angles, the amount of electron localization on the silicon site, and the relative amounts of s and p character of the electron-wave function.