PLD of Pb(Zr,Ti)O3 films: Phase formation on various substrates

Pulsed laser deposition (PLD) was used to deposit Pb(Zr52Ti48)O3 (PZT-5A) thin films on various substrates (SrTiO3, MgO, polycrystalline Yttria-stabilized ZrO2 (YSZ) and Al2O3). Furthermore, epitaxial YBa2Cu3O7−x on SrTiO3/Al2O3, which is serving as bottom electrode, was covered with PZT by PLD. The phase formation of two phases of PZT, the stable ABO3 with perovskite structure and the metastable A2B2O6O phase with pyrochlore structure, was investigated by XRD in dependence of substrate material, deposition temperature and film thickness. The ferroelectric P(E)-hysteresis of the films was measured and discussed with respect to the above mentioned points. A favoring of the perovskite phase formation was found on SrTiO3, a mixture of perovskite and pyrochlore on MgO, whereas YSZ substrates lead to the growth of 100% pyrochlore films under comparable deposition conditions. On polycrystalline Al2O3 substrates an additional YBCO layer allows the deposition of almost pure perovskite PZT.