Oscillatory deviations from classical Fowlerhyphen;Nordheim tunneling were measured in MOS capacitor structures with dry oxides ranging in thickness from 30 to 75 Aring;. The silicon wasptype, the metallization chromehyphen;gold, and the direction of tunneling that corresponding to electrons being injected from the metal into the SiO2conduction band. The observed variation of oscillation phases and amplitudes with oxide thickness suggests the following conclusions. The Sihyphen;SiO2interface is independent of oxide thickness only for thicknesses greater than 65 Aring;. At lower thicknesses, the barrier height at the interface decreases slowly with oxide thickness at a rate on the order of 10 mV/Aring;. At higher thicknesses, the barrier height is 4.08 eV. The interface is abrupt to within a few angstroms. The energy dispersion relationship within the SiO2conduction band is parabolic, at least up to 3 eV above the band edge, with an effectivehyphen;massndash;tondash;freehyphen;electronhyphen;mass ratio of unity. The mean free path within the SiO2conduction band is on the order of 13 Aring;.
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