We used double electron-beam coevaporation to fabricate TiO(2)-SiO(2) mixed films. The deposition process included oxygen partial pressure, substrate temperature, and deposition rate, all of which were real-time computer controlled. The optical properties of the mixed films varied from pure SiO(2) to pure TiO(2) as the composition of the films varied accordingly. X-ray diffraction showed that the mixed films all have amorphous structure with a SiO(2) content of as low as 11%. Atomic force microscopy showed that the mixed film has a smoother surface than pure TiO(2) film because of its amorphous structure.

Linear and Bruggeman's effective medium approximation models fit the experimental data better than other models.

Ba,Sr)TiO 3 ͑BST͒ films were fabricated on Pt/TiN/Ti/Si substrates by low temperature radio frequency magnetron cosputtering at 300°C. Material and electrical properties of BST films sputtered at low temperatures are significantly affected by the O 2 /(Ar ϩ O 2 ) mixing ratio ͑OMR͒. Plasma emission spectra indicate that the deposition rate declines at a higher OMR due to oxide formation on the target surface. The dielectric constant of the BST films can reach a maximum of 364 at 5% OMR. The ten-year lifetime of the time-dependent dielectric breakdown implies that the reliability of the capacitor can be enhanced at a higher OMR due to compensation of oxygen vacancies and smaller grain sizes. Current-voltage analysis indicates that the leakage current of the Pt/BST/Pt capacitor is limited by Schottky emission ͑SE͒/Poole-Frenkel emission ͑PF͒ at a lower/higher applied field. The applied field boundary between SE and PF shifts toward higher field as OMR increases. Moreover, an energy band model was proposed and this leakage mechanism was discussed.

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We used the electron-beam evaporation method in various oxygen partial pressure environments to deposit TiO(2) thin films on various glass substrates at 300 degrees C. We found the threshold oxygen partial pressures above which the film is transparent are different for films on various substrates. Below the threshold oxygen partial pressure, the refractive index and the extinction coefficient of the films varied from substrate to substrate. The films on substrates with higher threshold oxygen partial pressure were associated with a higher extinction coefficient and a higher growth rate. These phenomena are correlated with the appearance of rutile phase in the anatase phase, which is also correlated with variations in the Al(2)O(3) and Na(2)O content in the substrates. The Al(2)O(3) content in the substrate tends to enhance the formation of rutile phase in the film and to give a higher extinction coefficient for the film, while the Na(2)O content in the substrate tends to retard the rutile formation in the film and to give a lower extinction coefficient for the film.