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Recently, people have become interested in fine metal particles such as Au,Ag,Pt and Pd because of their importance in applications such as optical devices, electronic devices and heterogeneous catalysis. (1 to approximately 3) In particular, anisotropic fine metal particles have been researched as one of the key technologies to light control. We propose a new technique for preparation of anisotropic Au fine particles. SiO2 film dispersed Au fine particles was prepared by sol-gel method on TiO2 film made by sputtering. Silicon alkoxides and Au salts were used as raw materials for SiO2 film dispersed Au fine particles. The gel film was given heat- treatment at 300 degrees Celsius, and then Au salts we decomposed into Au fine particles. It was identified by TEM (transmission electron microscope) observation that anisotropic Au fine particles were trapped at the interface between SiO2 film and TiO2 film. In addition, compositional distribution in depth direction was investigated. It was confirmed by X-ray photoelectron spectroscopy that Au was distributed on the interface between TiO2 film and SiO2 film and the SiO2 film surface. Furthermore, the polarized light spectrum of Au fine particles separated out on the interface between TiO2 film and SiO2 film were measured, and as a result a polarized absorption spectrum caused by a minor axis and a major axis of Au fine particles were observed.
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