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Effects of post-annealing on the depth profile of oxygen content of indium tin oxide (ITO) films on glass substrates have been investigated. Absolute oxygen content of the films was estimated by a high-energy ion beam technique. The electrical properties and the oxygen contents, measured before and after post-annealing in vacuum, have been compared for films deposited under different conditions. Our present results implied that oxygen deficiency at the film surface, induced by post-annealing, might be responsible for the observed improvement of the electrical properties.

The enhancement factor of oxygen of 16O(α, α)16O resonance for a Rutherford backscattering cross section has been investigated using SiO2 films of various thicknesses. A new procedure to accurately extract the resonant oxygen height from a raw spectrum has been proposed. With this procedure, the dependence between the film thicknesses and resonant signals has been investigated, and was found to agree well with a computer simulation within experimental error. Using the enhancement factor, the depth dependence of oxygen concentration in the YBa2Cu3O x /MgO systems has been estimated accurately. Estimations of the accuracy of elastic backscattering analysis are also given.

Depth profiling of the oxygen concentration of indium tin oxide (ITO) films on glass substrates has been investigated using a high-energy ion beam. Hot-cathode Penning-discharge sputtering (HC-PDS) in the mixed gases of argon and oxygen was applied to fabricate the films. It is found that there is a correlation between the depth profile of oxygen concentration and the electrical properties. The effect of partial pressures of oxygen gas on the depth profile of the oxygen concentration and on electrical properties is discussed.

The crystalline quality (perfection or imperfection) of SrTiO3substrates and subsequent as-deposited YBa2Cu3Oxsuperconducting films has been investigated by a high-energy ion channeling technique. Analysis was performed as a function of depth, especially at 3 typical depth regions (surface, inside, interface), to clarify junction ordering features between substrates and films. Based on ion channeling measurements, it has been found that (1) disorders of substrates affect crystalline quality of films greatly at the interface regions, (2) the film reorders over a proper amount of YBa2Cu3Oxdisordered layers (as in buffer layers), (3) the film consists of an almost single domain. The crystalline quality of some SrTiO3substrates widely used in Japan has also been investigated and the common characteristics of distortions along thec-axis have been found.

A combined technique of low-energy Na+ ion scattering spectroscopy (Na+ ISS) and low-energy electron diffraction is applied to study the initial growth process of Ag films on Si(111) surfaces. In comparison with results obtained by Auger electron spectroscopy, the Na+ ISS is also found to reflect reasonably well the Stranski-Krastanov growth mode or the Frank van der Merwe growth mode. Moreover, owing to the extreme sensitivity of the outermost surface layer, the Na+ ISS gives information on changes in the surface morphology induced by the Ag adsorption and subsequent annealing.

The composition and crystalline structure of high-T c superconducting YBa2Cu3O x thin films formed on MgO(100) and Si(100) substrates have been investigated by Rutherford backscattering and channeling techniques. Y, Ba, Cu contents have been analyzed by employing a high-energy (over 4.5 MeV) 4He ions and large scattering angle (near 170°) condition, where Y, Ba and Cu peaks are clearly separated from each other. Oxygen concentration has been obtained through the use of low primary energy (below 2.5 MeV) and small scattering angle (below 150°) conditions, where the O peak is separated from the background. The crystalline quality of the films has also been investigated by ion channeling techniques.