SPUTTERING DEPOSITION OF PEROVSKITE THIN-FILMS WITH ATOMIC-SCALE CONTROLLED SURFACE

Perovskite thin films of (001) PbTiO3(PT), 5 to 200 nm in thickness, w ere deposited on miscut (001) SrTiO3 (miscut angle 1.7 degrees) by rf- magnetron sputtering. The surface of sputtered stoichiometric PT thin films comprised a periodic striped pattern which reflected the initial surface structure of the substrate. The periodic striped patterns com prised terraces and steps. The surface of the terraces region is atomi cally flat. The width of terrace and step height were 10 to 200 nm and 1 to 3 nm, respectively. The electron microscopic analysis suggests t hat the film shows a layer growth which corresponds to the Frank-van d er Merwe mode. The layer growth is governed by a step-flow mode. Depos ition under Pb-rich composition enhanced a two-dimensional nucleation and the two-dimensional nucleation was superposed on the striped patte rns. The surface area of PT thin films increased under Pb-rich composi tion. It is confirmed that epitaxial growth on the miscut substrate is essential for the synthesis of perovskite thin films with an atomic-s cale controlled surface. (C) 1997 Elsevier Science B.V.