Highly (100)-Oriented Thin Films of Sol-Gel Derived Pb[(Mg1/3Nb2/3)0.675Ti0.325]O3 Prepared on Textured LaNiO3 Electrode

Highly (100)-oriented thin films of Pb[(Mg1/3Nb2/3)0.675Ti0.325]O3 (PMNT) were fabricated by sol-gel method on (100)-textured LaNiO3 (LNO) metallic oxide electrode. The textured LaNiO3 layer was prepared by rf magnetron sputtering at 250° C on Si, SiO2/Si or Pt/Ti/SiO2/Si substrates. A well orientation match was found between the PMNT and LNO layers. The annealing temperature for obtaining a pure perovskite PMNT film was reduced for about 50° C by using the LNO-coated substrates comparing to that without. A well-developed grain structure was also formed for the former. Satisfactory dielectric and ferroelectric characteristics were observed from the (100)-oriented PMNT thin films prepared at 700° C on LNO, as compared to the randomly oriented one on Pt electrode. However, an increase of annealing temperature would cause a more serious out-diffusion of LNO which gradually deteriorated the property of PMNT films deposited on LNO.