Preferential growth of perovskite BaTiO3 thin films on Gd3Ga5O12(100) and Y3Fe5O12(100) oriented substrates by pulsed laser deposition

Abstract

This growth study is concerned with the structural compatibility of perovskite BaTiO₃ on garnet substrates Gd₃Ga₅O₁₂ and Y₃Fe₅O₁₂. Thin films (200 and 500 nm nominal thickness) have been deposited by pulsed laser deposition on the low-index orientations (100), (110) and (111) of Gd₃Ga₅O₁₂ single crystal substrates, as well as on a selection of Y₃Fe₅O₁₂ surfaces. The perovskite growth on the garnet (100) orientation exhibits good crystallinity as observed as higher X-ray diffraction intensities, (110)/(101) preferential growth and weak “rectangle-on-cube” in-plane epitaxy of the BaTiO₃ thin film. In contrast to that for growth on the (110) and (111) garnet substrates only polycrystalline BaTiO₃ thin films are observed. For X-ray photoelectron spectroscopy measurements, a scheme is presented for chemical analysis of a BaTiO₃ bulk and a surface component, and quantification of the surface concentration of the films is presented. A surface contamination of Bi traces seems to affect the strain on the BaTiO₃(110) reflex.