Enhanced ferroelectric properties of highly (100) oriented Pb(Zr_(0.52)Ti_(0.48))O_3 thick films prepared by chemical solution deposition

摘要

Ferroelectric Pb(Zr_(0.52)Ti_(0.48))O_3 (PZT) thick films with highly (100) preferential orientation have been prepared by chemical solution deposition process on Pt/Ti/SiO_2/(100)Si substrates and pyrolyzed at 350℃-450℃, then annealed at 650℃. The typical thickness of the films is 3.9 μm. Effects of the pyrolysis temperature and excess PbO on the orientation, dielectric and ferroelectric properties of PZT thick films have been discussed. Domain switching and depoling process were studied by piezoelectric force microscopy. (100) oriented PZT films exhibit enhanced electrical properties. The dielectric constant and loss tangent of the films are 1444 and 0.022 at 1 kHz, respectively. The remnant polarization increases from 27.6 to 34.6 μC/cm~2, and the coercive field decreases from 61.4 to 43.5 kV/cm, when the orientation of the films changes from the random orientation to the preferential (100) orientation. The leakage current density is 10~(-8) A/cm~2 at dc field of 0.25 kV/cm, and then increases to 10~(-6) A/cm~2 at 40kV/cm. The piezoelectric response of the oriented films is investigated by Piezoelecric Force Microscopy (PFM).