Ba0.6Sr0.4TiO3-Bi1.5Mg1.0Nb1.5O7 composite thin film capacitors with enhanced tunable performance for tunable device applications

摘要

This letter covers the fabrication of an electric field tunable device using Au/Ba0.6Sr0.4TiO3-Bi1.5Mg1.0Nb1.5O7/Au thin film capacitor and its observed tunable characteristics. Dielectric measurements indicated that the Ba0.6Sr0.4TiO3-Bi1.5Mg1.0Nb1.5O7 composite thin-film capacitors exhibited medium capacitance of about 442 pF, low loss tangent of 0.0053, and superior tunable properties at room temperature. Calculations of tunability and figure of merit (FOM) display a maximum value of 49.3% at 670 kV/cm and similar to 88, respectively. Both the FOM and coefficient of the dielectric nonlinearity are greater than that of the multilayers. We believe that the Ba0.6Sr0.4TiO3-Bi1.5Mg1.0Nb1.5O7 composite thin films based tunable capacitors presented in this letter could be a milestone for applications of tunable devices. (C) 2015 Elsevier B.V. All rights reserved.