Effect of substrate temperature on the properties of RuO2 films prepared by RF reactive magnetron sputtering

RuO₂ films have been prepared by rf reactive magnetron sputtering at different substrate temperatures (RT- 500 °C). The structural and electrical properties of these films have been studied. The film prepared at room temperature has a random orientation. As the substrate temperature is higher than 200 °C, the film shows a preferred orientation along the [101] direction. However, as the temperature is higher than 400 °C, the preferred orientation of the film changes from [101] to [200] direction. The grain size in the films shows a gradual increase as the temperature is increased. All the films are subject to a compressive stress and show a stress relaxation as the temperature is increased. The SEM pictures show that the film prepared at low temperature indicates a microcrystalline structure with very small size, and the films prepared at high temperatures result in polycrystalline structures of about 0.3 μm size. The measurements of the film resistivity show that all the films, except that prepared at room temperature, have a metallic behavior and the grain boundary scattering dominates the electrical resistivity of the films.