Preparation and characterization of transparent semiconductor RuO2-SiO2 films synthesized by sol-gel route

RuO2-SiO2 thin films with different Si/Ru molar ratios were prepared by the sol-gel method, using the hydrate ruthenium (III) chloride (RuCl3A.3.5H2O) and tetraethylorthosilicate as precursors. The crystal structure, resistivity, chemical bonding configuration, transmittance, carrier concentration, and mobility of the RuO2-SiO2 films were investigated before and after annealing in N2 ambient at 400-700A degree C. The resistivity of the RuO2-SiO2 films with different Si/Ru molar ratios decreased abruptly after annealing at 400-700A degree C. On the other hand, RuO2 phase precipitated in the RuO2-SiO2 films with different Si/Ru molar ratios after annealing. Fourier transform infrared spectroscopy spectra indicated that the water absorption occurs for as-deposited RuO2-SiO2 films with different Si/Ru molar ratios. The transmittance of all RuO2-SiO2 films presented transmittance maximums after annealing at 700A degree C. The carrier concentration and mobility of RuO2-SiO2 films are related to the Si/Ru molar ratios and the annealing temperature. This study discusses the connection among the material properties of the RuO2-SiO2 films and how they are influenced by the Si/Ru molar ratios and the annealing temperatures of RuO2-SiO2 films.