Thickness dependence of structural and piezoelectric properties of epitaxial Pb(Zr 0.52Ti 0.48)O 3 films on Si and SrTiO 3 substrates

We report the structural and longitudinal piezoelectric responses (d 33) of epitaxial Pb(Zr 0.52Ti 0.48)O 3 (PZT) films on (001) SrTiO 3 and Si substrates in the thickness range of 40 nm-4 μm. With increasing film thickness the tetragonality of PZT was reduced. The increase in d33 value with increasing film thicknesses was attributed to the reduction of substrate constraints and softening of PZT due to reduced tetragonality. The d 33 values of PZT films on Si substrates (∼330 pmV) are higher than those on SrTiO 3 substrates (∼200 pmV). The epitaxial PZT films on silicon will lead to the fabrication of high performance piezoelectric microelectromechanical devices. © 2006 American Institute of Physics.