Advantages of RuOx bottom electrode in the dielectric and leakage characteristics of (Ba,Sr)Ti0(3) capacitor

The crystal structure and electrical properties of (Ba,Sr)TiO3 (BST) films were investigated with three different bottom electrodes, Ti/Pt, RuOx and RuOx/Pt. On the RuOx and RuOx/Pt electrodes BST films were preferentially grown along the same orientations of electrodes, whereas BST films have no preferential orientation on the Pt electrode. The interfacial reaction, oxygen deficiency and hillock formation in the BST capacitors were obviously prevented by the RuOx bottom electrode, resulting in a high dielectric constant (300-305) and low leakage current density (10(-9) A/cm(2)).