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Amorphous SiO films are prepared by radio‐frequency planar magnetron sputtering in a background of argon. Inelastic electron tunneling spectra are presented of the films incorporated in Al/SiO/Pb tunnel junctions with the aluminium films pre‐ or post‐oxidized relative to the SiO deposition stage. Both the aluminium and lead junction electrodes are evaporated in a standard oil diffusion pumped, liquid nitrogen trapped vacuum system at a base pressure of 10−7 Torr; aluminium oxidation is achieved either by admitting oxygen into the vacuum chamber or by performing a low power dc oxygen glow discharge. Spectra obtained are similar, but not identical, to those obtained for evaporated SiO films. Different types of silicon hydride species are observed depending on the environment to which the SiO films are exposed after their deposition. Possible reactions of the films with water vapor are discussed which could produce the observed hydrides which are also assigned. Reverse bias tunneling spectra provide strong e...

Inelastic electron tunneling spectroscopy (IETS) is used to record the vibrational spectra of thin films of amorphous SiOx prepared by radio‐frequency planar magnetron sputter deposition in argon. The SiOx films are incorporated as the insulating barriers in aluminium SiOx/lead tunnel junctions, with no prior or subsequent oxidation of the aluminium films. Peak assignments are presented by comparison with infrared, Raman, and neutron scattering data for bulk silica, and a plausible stoichiometry is proposed. The SiOx barriers can be considered as model glass substrates for further adsorption studies, and hence extend the analytical capabilities of IETS.