Ferroelectric PbZr[sub(0.2)]Tio.[sub(8)]8[sub(O3)] Thin Films on Epitaxial Y-Ba-Cu-O

In earlier papers, the growth of high quality epitaxial thin films and heterostructures of bismuth titanate ferroelectric films by PLD was demonstrated?’**. It was also shown that the cuprate superconductors could be used as suitable bottom electrodes at room temperature. Epitaxial cuprate superconductor/bismuth titanate heterostructures were grown in-situ on single crystal SrTiC> 3 , LaAlC^? and on [001] Si** with a yttria-stabilized ZrC> 2 buffer layer for this purpose. In order to test the efficacy of the YBa2 Cu3 C>7 _x (YBCO) film as the bottom electrode for other ferroelectrics, we have grown PZT films on it by conventional sol-gel processing. The motivation for such an experiment was two-fold : (i) the results obtained from these experiments can be directly compared with those obtained with conventionally prepared films, i.e., those grown on Pt electrodes ; (ii) study the role of the YBCO layer as a suitable structural and chemical template that would promote the growth of well oriented or even epitaxial PZT films by sol-gel processing, which is currently a more mature processing route for making PZT films^. in this letter, we report first results of the ferroelectric properties of PbZro.2 Tio.8 O3 thin films grown on single crystalline c-axis oriented YBa2 Cu3 < > 7 thin films.