Textured PbTiO3-Al2O3 composite films prepared by chemical solution deposition

PbTiO3-Al2O3 composite films were prepared by chemical solution deposition on silica glass substrates using dip-coating and lead acetate trihydrate, titanium butoxide and aluminum isobutoxide as precursors. The phase composition, preferred orientation and crystallite dimension were determined by powder X-ray diffraction methods. The Al2O3 phase seems to be amorphous because of the absence of its diffraction peaks. The presence of this phase affects the preferential orientation of PbTiO3 crystallites. For the molar ratio n(Pb)/n(Al) = 2-4 most films show a strong texture of PbTiO3 crystallites with the a-axis oriented almost perpendicularly to the film plane and the c-axis oriented randomly in the film plane. The texture is much weaker in pure PbTiO3 films. The texture may originate from the minimization of surface and interface energies and from tensile stresses induced during film preparation. (C) 2001 Elsevier Science Ltd. All rights reserved.