Texture of gold-palladium couples

The crystal textures of polycrystalline films of gold-palladium couples on an oxidized silicon (100) substrates were investigated via x-ray diffraction (XRD) pole figures. Studies were performed on both as-deposited and thermally annealed films. Scanning electron microscopy (SEM) was used to examine the microstructures of the seed layer thin films as deposited. The {111} texture formation of gold-palladium thin film couples displayed a strong dependence on the nature of the underlying seed layer. Gold films deposited on a palladium seed layer revealed much less degree of {111} texture, than gold films deposited directly on a silicon dioxide surface. In contrast, palladium films deposited on polycrystalline gold films showed a higher degree of {111} texture, compared to palladium films deposited directly on silicon dioxide. The {111} texture of annealed gold-palladium alloy thin films was greater for palladium on gold than for gold on palladium. These results are interpreted in terms of the gold-palladium diffusion mechanism and the interaction of the condensing metals with the oxygens of the SiO2 substrate surface.