The characteristics of gold films deposited on ceramic substrate

A large quantity of gold (approximately 10 tonnes yearly) is consumed, all over the world, just to decorate ceramic and glassware. Due to their advanced chemical stability gold films are used for different high technology applications. The technologies for obtaining the best “liquid bright gold” were intensively studied, but the quality of the decor coatings (films) were empirically assessed. We proposed a scientific investigation of the characteristics of gold films, deposited on ceramic substrates, from “liquid bright golds”. The composition of the film has been determined by EDS (Energy Dispersive X-ray Spectrometry). The distribution of the elements was determined at the surface of the film and in cross-section. The surface distribution of the elements was uniform. The diffusion process of the film into substrate and the migration of the substrate elements at the interface region and into the film have been highlighted. The morphology of the film was studied by SEM microscopy. The grain size varied between 0.05 – 2 μm as a function of the film composition. The major phases from the film and interface were evidenced by X-ray diffraction. The film consisted of crystalline gold. At the interface region a solid solution of Au-ZrSiO4 was identified. Other phases were in amorphous state. The reflection spectra of the films were recorded from optical properties, using a mirror gold as standard, for comparison. The film with the smaller particle size reflected the UV — VIS wavelengths in the same way as a gold mirror. The adherence of the film on the substrate can be explained by the formation of an interfacial layer from solid solution Au−ZrSiO 4 and by diffusion processes.