Phase development in pulsed laser deposited Pb[Yb1/2Nb1/2]O3-PbTiO3 thin films

(1 - x) Pb[Yb1/2Nb1/2]O-3 - x PbTiO3 (PYbN-PT, x = 0.4 and 0.5) / SrRuO3 (SRO) heterostructures have been prepared by pulsed laser deposition (PLD) on < 100 >(pc)-oriented LaAlO3 (LAO) substrates (the subscript pc refers here to the pseudo-cubic perovskite subcell). Careful control of both lead volatilization and pyrochlore formation during the growth appears to be essential to obtain perovskite PYbN-PT thin films with good crystalline, electrical and ferroelectric properties. By utilizing PbO-enriched ceramic targets and adjusting deposition parameters such as the laser frequency, the chamber pressure, the target to substrate distance and/or the substrate temperature, high-quality thin films can be successfully grown with a single out-of-plane < 001 >(pc) orientation and an in-plane heteroepitaxial arrangement of [110], PYbN-PT // [110](pc). SrRuO3. When processed in the 560-660 degrees C temperature range, with a dynamic O-3/O-2 pressure of 300-400 mTorr and relatively high laser repetition rates, PYbN-PT films exhibit improved ferroelectric properties. The typical values of the remanent (P-r) and saturation (P-s) polarizations increase up to 50 and 80 mu C/cm(2), respectively. (C) 2000 Published by Elsevier Science S.A. All rights reserved.