Compositional Dependence of the Piezoelectric Properties in Pb(ZrxTi1-x)O3 Thick films Prepared by a Chemical Solution Deposition Process

Abstract

To investigate the compositional dependence of the piezoelectric properties in lead zirconate titanate (PZT) thick films, 2-micro m-thickness Pb(ZrxTi1-x)O3 (x=0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8) films were prepared on Pt/Ti/SiO2/Si substrates by a chemical solution deposition process. The prepared thick films were fabricated into disk shape structure using reactive ion etching with a diameter of 10 micro m and 20 micro m. The ferroelectric properties and longitudinal displacement of the PZT thick film disks were measured simultaneously with an atomic force microscope (AFM) connected with a ferroelectric test system (FCE). Piezoelectric constants, referred to as AFM d33, were calculated from unipolar driven strain-field curves. For ferroelectric properties, the coercive field Ec increased with decreasing Zr content, x, and remnant polarization Pr showed a peak at x= 0.4. On the other hand, the AFM d33 showed two peaks at x= 0.5 and 0.7. These tendencies are consistent with a simulation result for PZT ceramics (Yamamoto 1998 [1]). We suggest that the AFM d33 peak at x= 0.7 corresponds to the rhombohedral phase boundary between the high temperature, Rh (HT), and low temperature, Rh (LT) phases.