Deposition of epitaxial ferroelectric lead zirconate titanate and conducting oxide electrodes by pulsed laser ablation

Abstract

Layered thin film structures containing ferroelectric Nd doped lead zirconate titanate (PZT) and conducting lanthanum strontium cobalt oxide (LSCO) or high Tc superconducting YBa₂Cu₃O_7-δ (YBCO) compound were deposited in an in situ process by pulsed laser ablation using an XeCl excimer laser. The structures were grown on heated SrTiO₃ (STO) (100) and MgO (100) single crystal substrates. The structure, orientation relationships and degree of epitaxy and crystal perfection of the films were studied by X-ray diffraction and scanning electron microscopy (SEM). The PZT target composition was reproduced well in the films. Ferroelectric properties of PZT films and resistive properties of the structures with laser ablated Pt top electrodes were measured. For the best films, the remanent polarization was 15–20 μC/cm², the coercive field 60–75 kV/cm and the dielectric constant about 600.