Transmission, photoconductivity, and the experimental band gap of thermally grown SiO2films

摘要: Optical transmission and photoconductivity spectra (7-14 eV) the field dependence of are presented for thermally grown (amorphous) Si${\mathrm{O}}_{2}$ films. It is argued that clearest experimental determination band gap in can be obtained from its similarity to internal photoemission; a 9.3 eV amorphous deduced data. In view this result some recent band-gap determinations criticized literature on subject examined. The experiments were performed thin films (450-5000 \AA{}) produced by etching off silicon substrate using fabrication method which described detail. measurements Al-Si${\mathrm{O}}_{2}$-Si structures (Si${\mathrm{O}}_{2}$: 600-3500 \AA{}). Diode detecting photoluminescence possibly excitons also described. upper limit yield was determined as \ensuremath{\sim}${10}^{\ensuremath{-}4}$.