Stable platinum oxide films have been prepared through magnetron sputtering and have been analyzed on the bases of energy-sensitive microanalyses, x-ray diffraction, resistivity, and optical reflectance measurements. The complex dielectric function has been determined for various oxygen contents in the film covering the wave-number regime 50 cm−1–λ−1–50 000 cm−1. The vibrational properties are dominated through a strong band, centered at 765 cm−1, associated with a asymmetric stretching mode of the Pt—O bond. The films are amorphous, with chemical composition PtOx, where 1<x<2.1, and are considered as a homogeneous solid solution of PtO and PtO2. The materials system displays a conductor–insulator transition at x≥2, in connection with an optical band gap Eg of ∼1.2 eV in the fully oxidized state. The conduction mechanism over the whole range of compositions is thermally activated and is determined through a large density of localized states extending into the band gap. At x<2 the optical gap disappears, consistent with the semimetallic behavior of the materials system for this range of composition.

A rapid thermal oxidation process of silicon in N20 ambient was investigated using a commercially available reactor with a fixed wafer position and a gas flow parallel to the wafer surface. For such a configuration, thickness uniformities in the 2% range were obtained for the first time. The oxidation rate as a function of process temperature and time was investigated. A retardation in the N20 oxidation rate as compared to the oxidation in O2 ambient is explained by the formation of a nitrided interracial layer. A comparison of experimental results with an oxidation model calculation shows that this interface can affect either the oxidant diffusivity through the oxide or the reaction rate at the silicon surface. Infrared spectra of nitrided oxide films reveal a regular arrangement in the Si-O network, similar to that of high quality thermally grown oxides. A vibrational contribution to that spectrum from a Si-ON subnetwork is displayed. The accumulated charge to breakdown on metal-oxide-semiconductor capacitors as a function of the injected current density revealed different slopes for oxides either thermally grown or grown in N20. Hence, the projected lifetime for devices with N20 grown oxide under low operating fields is extended by one order of magnitude in comparison with th e thermal oxide.

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