Properties of Silicon-Oxygen Alloy Films Prepared from SiH4+CO2 Gas Mixture

Measurement of electrical properties, etch rates in HF (49%) and HF-HNO3 (49% HF:63% HNO3=1:20) solutions and X-ray photoemission spectra are reported for amorphous silicon-oxygen alloy films (a-SiO x :H) prepared by r. f. glow discharge decomposition of a SiH4-CO2 gas mixture. Activated band conduction is observed in the temperature range of 324-424 K. Though the addition of oxygen causes a decrease in the conductivity, the activation energy for conduction remains at a constant value of around 1.0 eV in the films with oxygen content x from 0.17 to 0.5. The broadening toward the high binding energy of the Si-2p core level in X-ray photoemission spectra with oxygen content is explained by the effects of oxygen atoms incorporated into the films.