Strain-relaxed structure in (001)/(100)-oriented epitaxial Pb(Zr,Ti)O3 films grown on (100) SrTiO3 substrates by metal organic chemical vapor deposition

Epitaxial (100)/(001)-oriented tetragonal Pb(Zr,Ti)O3 films above 1 μm thick were grown on (100)SrTO3 substrates by pulsed metal organic chemical vapor deposition, and the films with Zr/(Zr+Ti) ratios up to 0.43 were found to have a strain-relaxed domain structure. The domain structure determined by the volume fraction of (001) orientation (mainly decided by the thermal strain above the Curie temperature) and the lattice parameters dependent on the Zr/(Zr+Ti) ratio are explained by a geometrical model consistent with previous results for PbTiO3 films [J. Appl. Phys. 104, 064121 (2008)].