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61 MHz). The 12H NMR spectra were recorded in methylene chloride (Aldrich, Gold Label), and the solvent signal (5.32 ppm) due to 2H in natural abundance was used to calibrate the field.The infrared spectra of the coals (2-4%) in dry potassium bromide were recorded with a Nicolet 20 spectrometer. The pellets were dried in vacuo at 65 °C for 20 h before the spectra were recorded.

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Variables affecting the passivation capability of Cu(Mg) alloy films, which were sputter deposited from a Cu (4.5 atom %) target, have been investigated. As-deposited Cu(Mg)/SiO 2 /Si multilayer samples were annealed for 30 min in various oxygen ambients at pressures ranging from 10 mTorr to 30 Torr and at various temperatures in the 200-800ЊC range. The results show that the passivation capability of a Cu(Mg) alloy film is a function of annealing temperature, O 2 pressure, and Mg content in the film. Increasing the annealing temperature favors formation of a dense MgO layer on the surface. Decreasing the O 2 pressure enhances the preferential oxidation of Mg over Cu. Furthermore, increasing the Mg content in the Cu(Mg) film promotes formation of a dense MgO layer. Vacuum preannealing before taking the as-deposited samples to O 2 annealings was found to be very effective in segregating Mg to the surface, facilitating the passivation capability of the Cu(Mg) alloy film even when the Mg content is low. In the current study, self-aligned MgO layers with low resistivity and an effective passivation capability over the Cu surface have been obtained by manipulating these factors when Cu(Mg) thin films are annealed.