Leakage Current Characteristics of (Ba,Sr)TiO₃ Thin Films Deposited on Ru Electrodes Prepared by Metal Organic Chemical Vapor Deposition

Abstract

Leakage current characteristics of (Ba,Sr)TiO 3 (BST) thin films deposited by metal-organic chemical vapor deposition (MOCVD) on Ru bottom electrodes were investigated. CVD-BST thin film on an Ru electrode showed much higher leakage current density than that on the Pt electrode. In the case of the CVD-BST thin film deposited on the PVD-BST(30 Å)/Ru or N 2 O-plasma-treated Ru electrode, the leakage current density showed a very small value of about 2×10 -8 A/cm 2 at ±1 V and the dielectric loss was about 0.006. It was found that oxygen atoms adsorbed on the surface of the Ru bottom electrode during the deposition of PVD-BST or N 2 O plasma treatment played a key role in restoring the barrier height at the bottom interface.