Influence of Nd Doping on the Properties of SrTiO3 thin Films Synthesized by PLD on Different Substrates

M.   R. S.   Silva; M.   C. F.   Alves; V.      Bouquet; S.      Députier; G.   P.   Casali; I.   T.   Weber; S.   M.   Zanetti; E.      Longo; M.      Guilloux-Viry; A.   G.   Souza; I.   M. G.   Santos

Abstract

SrTiO₃, SrTi_0.99Nd_0.01O₃ and Sr_0.99Nd_0.01TiO₃ thin films were synthesized by pulsed laser deposition at 700 ^°C on different substrates (silica, R-sapphire, (100) LaAlO₃ and (100) MgO). The influence of Nd³⁺ substitution into the A and B sites of SrTiO₃ perovskite on film growth was studied. The films were characterized by X-ray diffraction (θ–2θ, θ- and θ-scans), micro-Raman spectroscopy, UV–Vis spectroscopy and field-emission scanning electron microscopy. All of the films exhibited a (h00) orientation and high-quality epitaxial growth on LaAlOθ. The films grown on MgO, with the exception of the SrTiNd_0.01O₃ film, also exhibited a (h00) orientation. The polycrystallinity of the SrTi_0.99Nd_0.01O₃ film may be related to the increased lattice distortion when Ti⁴⁺ was replaced with Nd³⁺. A polycrystalline growth was observed for all of the films deposited on silica and R-sapphire, as expected. The Raman results showed that Nd doping led to an increase in the short-range disorder. The morphology strongly depended on the nature of the substrate and on Nd doping, specially in the case of SrTi_0.99Nd_0.01O₃.