Thickness dependence of structural and piezoelectric properties of epitaxial Pb(Zr0.52Ti0.48)O3 films on Si and SrTiO3 substrates

We report the structural and longitudinal piezoelectric responses (d33) of epitaxial Pb(Zr0.52Ti0.48)O3 (PZT) films on (001) SrTiO3 and Si substrates in the thickness range of 40nm–4μm. 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 d33 values of PZT films on Si substrates (∼330pm∕V) are higher than those on SrTiO3 substrates (∼200pm∕V). The epitaxial PZT films on silicon will lead to the fabrication of high performance piezoelectric microelectromechanical devices.