Heteroepitaxial Growth and Ferroelectric Properties of PbZr_0.52Ti_0.48O₃/SrRuO₃ Structure on TiO₂-Terminated SrTiO₃ (100) by Pulsed Laser Deposition

Abstract

Epitaxial ferroelectric PbZr_0.52Ti_0.48O₃ (PZT)/SrRuO₃ (SRO) heterostructures have been grown on TiO₂-terminated SrTiO₃ (100) (STO) substrates by pulsed laser deposition. Atomically flat terraces of STO substrate were obtained by chemical (BHF pH–5.8, ultrasonic 10 sec) and physical (O₂, 1000°C, 60 min) treatment. The 7 nm thick-SRO thin films indicate transition from three-dimension to two-dimension growth mode. The 14 nm thick-SRO film shows a structure of terraces and steps, which typically have one unit-cell height. The growth relationship of PZT(00l)/SRO(h00)/STO(h00) has been achieved. No diffraction peaks from lead deficient pyrochlore phases were observed in the XRD pattern, indicating that the film is a single crystal. The 2P_r and 2E_c values of Pt/PZT/SRO/STO structure were found to be 64 μ C/cm² and 191 kV/cm, respectively, at the applied voltage of 5 V.

Keywords:

• TiO₂-terminated SrTiO₃
• Heteroepitaxal growth
• SrRuO₃
• PbZr_0.52Ti_0.48O₃
• Pulsed laser deposition

ACKNOWLEDGEMENTS

This work was supported by Korea Research Foundation Grant (KRF-2002-042-D00066).