A lead ruthenite, Pb2Ru2O7-x (PRO), having a Pb-based cubic structure and being able to supply for loss of Pb and O in chemical solution deposited PZT (Pb(Zr0.35Ti0.65)O-3) films was introduced into Pt/PZT interface to improve the ferroelectric properties of the PZT films. The resistivity of PRO/Pt hybrid structure was approximately 35-45 muOmega cm and the surface roughness remains constant irrespective of annealing temperature. The 2P(r) (remanent polarization) values measured at 5 V in Pt/PZT/Pt, Pt/PZT/PRO (35 nm)/Pt, and Pt/PRO (35 nm)/PZT/PRO (35nm)/Pt capacitors are 52, 67, and 75 muC/cm(2), and the 2E(c) (coercive field) values are 224, 218, and 217 kV/cm, respectively. After 2.0 x 10(9) switching cycles, the percentages of retained remartent polarization is approximately 17% for Pt/PZT/Pt, 59% for Pt/PZT/PRO (35 nm)/Pt, and above 95% for Pt/PRO (35 nm)/PZT/PRO (35 nm)/Pt capacitor. The PRO interlayers inserted between Pt and PZT played an important role in improving the ferroelectric properties of PZT thin films for nonvolatile memory device application. (C) 2004 Elsevier B.V. All rights reserved.