Thick Epitaxial Pb(Zr0.35,Ti0.65)O₃Films Grown on (100)CaF₂Substrates with Polar-Axis-Orientation

(100)/(001)-oriented tetragonal Pb(Zr,Ti)O 3 (PZT) films, which were thicker than 2 µm, were epitaxially grown on SrRuO 3 -covered (100)Si, (100)KTaO 3 , (100)SrTiO 3 , and (100)CaF 2 substrates by metal organic chemical vapor deposition. The volume fraction of the (001)-orientation almost linearly increased as the thermal strain increased during the cooling process from the deposition temperature to the Curie temperature. Consequently, perfectly (001)-oriented, i.e., polar-axis-oriented, thick films were obtained on CaF 2 substrates with a remanent polarization of 71 µC/cm 2 . This approach to grow polar-axis-oriented PZT thick films enabled the intrinsic piezoelectricity of PZT itself to be clarified, and has potential in novel applications.