The effects of the amount of RuO2 added in the Pt film on the electrical properties of the deposited Pt-RuO2 film on the n(2+)-poly-Si substrate by using metal mask of 500 mu m dot in size were investigated at the temperature range of 500-700 degrees C in air. When the Pt film was prepared without RuO2 addition, it showed the higher total resistance and nonlinear characteristics, attributed to the oxidized layer at the Pt/n(2+)-poly-Si interface formed by reaction between the indiffused oxygen through Pt grain boundaries and Si during annealing in air. The Pt layer fabricated by RuO2 incorporation exhibited the lower total resistance and ohmic behavior up to 700 degrees C and suppressed the reaction of Pt-silicide up to 800 degrees C. In the latter case, the incorporation of ruthenium dioxide (RuO2) into the Pt bottom electrode layer led to the retardation of the interdiffusion of oxygen, Si, and Pt up to 700 degrees C, resulting from RuO2 stuffing effect in the polycrystalline Pt film. Consequently, this implies that the RuO2-stuffed Pt layer is expected to perform as a bottom electrode as well as diffusion barrier.