The Study On Structure And Properties Of CeO₂-TiO₂ Films Prepared By Sputtering

The thesis introduces the development of coating glasses and expatiates the developing trends of energy save coating glasses in future: low cost materials, high efficiency making technology, high quality and good function. Ce02-TiOz complex films have received abroad attention as their high reflective index, excellent Ultraviolet ray (UV) absorbing properties, high charge-storage capacity and good electrochemical reversibility. They are important materials for the smart coating glasses.A different Ce /Ti molar ratio is mixed, milled, and sintered with CeO2-TiO2 complex ceramic target to make Ce02 films, Ti02 films, CeO2-TiO2 complex films by means of RF magnetism sputter at different sputter conditions.It is important to study the relationship between the structures and the properties of coating films on glasses. The thesis studies the films ' structures and properties by means of scanning Electron microscope (SEM), Transmission electron microscope (TEM), X-ray photoelectron spectrometer(XPS), Raman spectrometer, UV-vis spectrometer, Thin films analysis apparatus, and Target materials.It is the difference of atom ordinal number and sputter area that results in Ce prior sputter and Ce/Ti molar ratio in films is 50% more than Ce/Ti molar ratio in practical target design.The particle sizes of the Ce02-Ti02 complex films are in nanoscale about 3-50nm. The surface of Ce02 - Ti02 films were very smooth and difficulty to crystallization. The CeO2-TiO2 complex films were nanocrystalline microstructure or microcrystalline even if to heat the substrates or to anneal the films. The CeO2 and TiO2 nanocrystalline were not easy congregate and bigger because of heterogeneity interface disturb and have many defect. The nanocrystalline or micrecrystalline size effect of films greatly affect to the optical characteristic of films.The indirect optical gaps of Ce02-Ti02 complex films above 0. 8 molar ratio of CeO2/Ti02 are smaller, when compared with pure CeO2 films or pure TiO2 films. The indirect optical gaps of Ce02-Ti02 are Eg =2.62 0. 04 eV, CeO2 films are Eg = 3. 08 0. 02 eV, TiO, films are Eg = 3. 35 0. 02 eV. The absorption edges wavelengths and cutoff wavelengthsof CeO2-Ti2;. complex films are red shift, if compared with pure Ce02 films or pure TiO2 films. The transparent spectrum of Ce02-Ti02 complex films appears band trail clearly.The thesis draws a conclusion that the decrease of band gaps of Ce02-Ti02 complex films are caused by (1) the nanocrystalline size effect of films (2) Ce-Ti doped one another. The indirect optical gaps of Ce02-TiOa complex films induce the absorption edges wavelengths red shift so that the films have excellent properties of Ultraviolet absorbing. The study on Ce02-Ti02 films can supply a theory and experiment guidance for making Ce02-Ti02 coating on glasses by RF sputtering.