Superconducting YBa2Cu3O7-χ (YBCO) thin films were deposited on Si (111) substates with a conductive intermediate layer of Ag/In2O3. In2O3 was prepared by the d.c. magnetron method and a silver thin film was evaporated on the In2O3/Si (111). The YBCO thin fims were deposited by d.c. magnetron sputtering. The conductive In2O3 thin film was used to minimize the interdiffusion between silicon and the YBCO superconducting material. The silver thin film improves the zero-resistance temperature, transition temperature width, and the critical current density of the superconducting YBCO film in the YBCO/In2O3/Si system. Films of YBCO on the Ag/In2O3/Si substrate have zero resistance at 85K and a critical current density of 2.0×103 A cm-2 at 77K. The XRD spectrum indicates that the superconducting thin films have a preferential c axis oriented structure. Auger electron spectroscopy depth profiling was used to analyse the interfaces.

A new high quality transparent conductive thin film In O: Mo (IMO) was prepared by conventional thermal reactive evaporation at the substrate temperature of approximately 350 C. From X-ray photoelectron spectroscopy XPS and X-ray diffraction (XRD) analysis of IMO films, it was confirmed that Mo6+ substituted In6+ without changing the cubic bixbyite structure of In2O3 and there were no new compounds in IMO as well. One atom of dopant contributes with more electrons to the electrical conductivity and at the same carrier concentration there is fewer dopant in IMO than in other doped oxides. So, the IMO film exhibits simultaneously higher values of Hall mobility, electric conductivity, visible light transmittance, infrared reflectance and plasma wavelength. An electrical resistivity as low as 1.7×0-4Ωcm was obtained, while the infrared reflectance above 4μm and the average total visible light transmittance of the IMO film plus the glass substrate were both over 80%, and the plasma wavelength was at approximately 2.2μm. IMO is more suitable for the energy efficient windows used in cold climates or even for optoelectronic device applications. © 2001 Elsevier Science B. V. All rights reserved.

We developed a novel transparent conductive film, molybdenum-doped indium oxide (IMO). Using normal thermal reactive evaporation without any special treatments, IMO films have been prepared on normal glass microscope slides at about 350℃ with electrical resistivity of 1.731024 Vcm, mobility over 100 cm2 V21 s21, and an average spectral transmittance in the visible region over 80%. From x-ray photoelectron spectroscopy and x-ray diffraction spectra of the IMO films, it is confirmed that the lattice of IMO is the same as that of In2O3 of cubic bixbyite structure, Mo61 substitutes for In31 in In2O3, and there are no new compounds in IMO. The valence difference of 3 between Mo61 and In31 is of great advantage to the IMO film with high conductivity and high transparency simultaneously. © 2002 American Vacuum Society.

Ti1−XSbXO2 samples were obtained from dip-coating sol-gel method and a subsequent anneal at 450℃. They had an average crystallite size of 13.3-20nm. Cyclic voltammograms taken under ultraviolet (UV) and Xe lamp illumination in a 0.5M Na2SO4 electrolyte showed that the Sb-doped samples had greater photocurrent densities than pure titania electrode, with an optimal Sb concentration of 0.2%. Oxidative peaks were observed in the cyclic voltammograms obtained in the dark after certain exposure duration to UV light. X-ray diffraction patterns and Raman spectra show a phase transformation from brookite to anatase in the samples with Sb concentration up to 0.2%. Ti4+ ions were substituted by Sb to form the anatase structure of Sb-O-Ti, improving the crystallization efficiency. The Sb-Sb bonds were formed due to the introduction of excessive Sb atoms.

Photoluminescence (PL) from SiOx (0<χ<2) thin films, prepared byevaporation of SiO powder onto the Si (100) substrate followed by thermal annealing, was investigated for various film thickness and annealing temperatures. For the film thickness ranging from 120 to 700nm and annealing at 1100℃ for 30 min in nitrogen, the Si nanocrystals (nc-Si) embedded in SiO2 matrix were formed due to the phase separation process, and the PL of nc-Si exhibited a continuous red-shift with increasing film thickness in an exponential decay manner. This thickness dependence was explained by a model modified from that of Zacharias and Streitenberger (2000 Phys. Rev. B 62 8391) regarding the nucleation barrier for Si clusters versus their distances away from the substrate. Further, for the film thickness of 270nm and annealing temperature ranging from 700 to 1100℃, it was found that a green/yellow PL structure developed at elevated annealing temperatures, which reached the maximum in intensity at 900℃, and then dropped down for higher annealing temperatures. This PL emission was identified as due to the structural defects mainly consisting of oxygen vacancies in SiO2 matrix.