Dielectric and piezoelectric properties of (x)Pb(Mg1/3Nb2/3)O-3-(1-x)Pb(Zr1/2Ti1/2)O-3 thin films prepared by the sol-gel method

The dielectric and piezoelectric properties of sol-gel derived (x)Pb(Mg1/3N b2/3)O-3-(1-x)Pb(Zr1/2Ti1/2)O-3[(x)PMN-(1-x)PZT] thin films were investigat ed as a function of PMN content (x=0-1). For all compositions in the (x)PMN -(1-x)PZT thin films, a well-developed perovskite phase with (111) preferre d orientation was obtained at the annealing temperature range of 700-800 de greesC. With increasing PMN content, the dielectric constant increased, whi le the remnant polarization and coercive field decreased. The enhanced diel ectric properties were shown in the region of x=0.2. At this composition, t he dielectric constant and remnant polarization were 1750 and 12.75 muC/cm( 2), respectively, which indicate that the morphotropic phase boundary (MPB) exists near the composition of x=0.2. The transverse piezoelectric coeffic ient (d(31)) showed a maximum value of -84 pC/N at x=0.2. These results con firmed that enhancement of the dielectric constant and remnant polarization improved the piezoelectric properties at the MPB. (C) 2001 American Instit ute of Physics.