Ruthenium dioxide (RuO2) thin films are evaluated as a bottom electrod
e for SrTiO3. It was found that a thin RuO2(50 nm)/Ru(20 nm) layer on
Si is quite effective as a barrier layer for both orygen atoms and met
als when depositing SrTiO3 ata relatively low temperature of 450-degre
es-C. To test its suitability for high-temperature processes such as C
VD of SrTiO3, the RuO2/Ru electrode on Si was annealed in air at 600-d
egrees-C for 1 hour. Even under this severe condition, the electrode u
sing 100-nm-thick RuO2 was sufficient for preventing oxygen diffusion
into Si.