The effect of interface on the electrical properties of (Ba, Sr)TiO3 adopting the perovskite electrodes

Perovskite type conducting materials (Ca, Sr)RuO3 and (Ba, Sr)RuO3 were prepared by rf magnetron sputtering as bottom electrodes for (Ba, Sr)TiO3 thin film capacitors. The crystallinity, interface property, and electrical properties of the (Ba, Sr)TiO3 capacitor applying the perovskite oxide electrodes were investigated. The interface between the dielectric and the electrode were analyzed by high-resolution electron microscopy and Auger electron spectroscopy. The interface had a marked effect on the electrical properties of the (Ba, Sr)TiO3 thin films. Dielectric constant for the (Ba, Sr)TiO3 had considerable dependence on the thickness of interfacial layer. The leakage current density of the capacitor was sensitive not only to the structural match but also to the chemical match between (Ba, Sr)TiO3 and the electrode.