2026-04-17T01:10:44Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/285512026-01-30T07:35:13Zcom_2072_1033col_2072_452950

Growth and physical properties of highly oriented La-doped (K,Na)NbO3 ferroelectric thin films Vendrell Villafruela, Xavier Raymond, Oscar Ochoa Guerrero, Diego A. García García, José Eduardo Mestres, Lourdes Universitat Politècnica de Catalunya. Departament de Física Aplicada Universitat Politècnica de Catalunya. CEMAD - Caracterització Elèctrica de Materials i Dispositius Àrees temàtiques de la UPC::Física Ferroelectric thin films Pyrolysis Ceramics Chemical solution deposition (K0.5Na0.5)NbO3 Ferroelectric Thin films Pyrolysis temperature Electrical-properties Ceramics Ferroelectricitat Piròlisi Ceràmica Lead-free (K,Na)NbO3 (KNN) and La doped (K,Na)NbO3 (KNN-La) thin films are grown on SrTiO3 substrates using the chemical solution deposition method. The effect of adding different amounts of Na and K excess (0-20 mol%) is investigated. The results confirm the necessity of adding 20 mol% excess amounts of Na and K precursor solutions in order to avoid the formation of the secondary phase, K4Nb6O17, as confirmed by X-ray diffraction and Raman spectroscopy. Moreover, when adding a 20 mol% of alkaline metal excess, the thin films are highly textured with out-of-plane preferential orientation in the [100] direction of the [100] orientation of the substrate. Doping with lanthanum results in a decrease of the leakage current density at low electric field, and an increase in the dielectric permittivity across the whole temperature range (80-380 K). Although the (100)-oriented KNN and KNN-La films exhibited rounded hysteresis loops, at low temperatures the films show the typical ferroelectric hysteresis loops. (C) 2015 Elsevier B.V. All rights reserved. Postprint (author’s final draft) 2015-02-27 Article Vendrell, X. [et al.]. Growth and physical properties of highly oriented La-doped (K,Na)NbO3 ferroelectric thin films. "Thin solid films", 27 Febrer 2015, vol. 577, p. 35-41. 0040-6090 https://hdl.handle.net/2117/28551 10.1016/j.tsf.2015.01.038 eng http://www.sciencedirect.com/science/article/pii/S0040609015000723 http://creativecommons.org/licenses/by-nc-nd/3.0/es/ Open Access Attribution-NonCommercial-NoDerivs 3.0 Spain 7 p. application/pdf