Comparative study of grain sizes and orientation in microstructured Au, Pt and W thin films designed by laser interference metallurgy

Abstract The physical and chemical properties of materials are strongly correlated with their microstructure. Although size effects may lead to a more complex interpretation of the gained results, much effort is invested in the microstructural design of metallic thin films and the detailed understanding of dependencies, such as the impact of thermal annealing on the corresponding grain and micro-texture characteristics. The main focus of this work is the microstructural design of periodic arrays in Au, Pt and W thin films using laser interference patterns. Due to the high and localized periodic intensity profile of the nanosecond laser pulse, a precise redesign of the film microstructure in terms of recrystallization, phase arrangement, texture, residual stresses or topography is possible. We demonstrate the possibility of controlling the recrystallization process by adjusting the laser energy density. Furthermore, dynamic aspects of the induced recrystallization process such as temperature distribution were studied based on thermal simulations. The grain size distribution and the micro-texture were determined by electron backscatter diffraction. The size and scale of the tailored structures produced by this technique could be beneficial with regard to thermo-electrical as well as tribo-mechanical applications.