Structural characterization of PbTi0₃, Sm_0.6Nd_0.4NiO₃ and NdMnO₃ multifunctional Perovskite thin films

¹ Laboratoire des Matériaux et du Génie Physique (CNRS UMR 5628), Minatec Bâtiment INPG, parvis Louis Néel, BP 257, 38016 Grenoble Cedex 1, France
² Schneider Electric Industries S.A.S., 37 Quai Paul Louis Merlin, 38050 Grenoble Cedex 9, France
³ Laboratoire de Physico–Chimie des Matériaux, Faculté des Sciences de Monastir, Département de Physique, 5019, Monastir, Tunisie
⁴ P2M, Institut Jean Lamour, Nancy Université, Bd. des Aiguillettes, 54506 Vandoeuvre-ls-Nancy cedex, France

^a e-mail: mboudard@minatec.inpg.fr

Abstract

Different multifunctional (PbTiO₃, Sm_0.6Nd_0.4NiO₃, NdMnO₃) thin films were grown by metalorganic chemical vapor deposition (MOCVD) technique on SrTiO₃ and LaAlO₃ substrates. TEM and X-ray diffraction measurements reveal that almost single crystalline thin films can be epitaxially grown on the top of substrates. The relationship between the crystallographic orientation of the films and those of the substrates were determined by reciprocal space mapping and TEM analyses. PbTi0₃ thin films appear to be under tensile or compressive strain according to the different mismatch of their cell parameter with those of the substrate. Relaxation mechanism as a function of the film thickness arises from coexistence of different type of domains and size and strain effect are analyzed. SmNiO₃ thin films present diffuse scattering strikes and are less well organized when compared to PbTi0₃ thin films. Different domains are observed as well as an additional parasitic phase close to NiO. Its regular distribution can be associated to reduced transport properties. Preliminary observations on NdMnO₃ thin films show that an amorphous phase is obtained during MOCVD that can be transformed in a single crystalline film by annealing. The films are under tensile or compressive strain according to the different mismatch of their cell parameter with those of the substrate. Magnetic properties are investigated.