Complex domain structure in relaxed PbTiO3 thick films grown on (100)cSrRuO3//(100)SrTiO3 substrates

Domain structures of epitaxial PbTiO3 films grown on (100)(c)SrRuO3//(100)SrTiO3 substrates by metalorganic chemical vapor deposition were investigated by x-ray diffraction (XRD) and piezoresponse force microscopy (PFM) techniques. It was found that with increasing film thickness, the domain structure changed from simple (001) polarization orientation to a complicated mixture of (001) and (100) orientations. PFM mappings showed that in the thicker films (similar to 1100 nm), the zigzag (001)/(100) domain boundaries made an angle of approximately 87 degrees instead of 90 degrees typically observed in (001)/(100) domain patterns in thinner (<300 nm) films. Full-relaxed tilting angle theta(1)+theta(2)+theta(3)=3.4 degrees obtained from cross-sectional profile analysis of topological step-terrace structure was in good agreement with 3.4 degrees and 3.6 degrees angle values obtained from XRD measurements and theoretical prediction, respectively. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4746078]