Structure and electrical properties of Mn doped Bi(Mg1/2Ti1/2)O3-PbTiO3 ferroelectric thin films

The Mn doped 0.63Bi(Mg1/2Ti1/2)O-3-0.37PbTiO(3) (BMT-0.37PT-xMn, x = 0-0.01) thin films were deposited on Pt(1 1 1)/Ti/SiO2/Si substrates by a sol-gel method. The effect of the Mn doping concentration on the structure and electrical properties of BMT-0.37PT thin films was studied. The X-ray diffraction data indicate that the B-site Mn substitution does not change the perovskite structure of the films. The X-ray photoelectron spectra show that Mn ions mainly exist as Mn3+ except for a few as Mn2+ for the 1 mol% Mn doped BMT-0.37PT film. Moreover, it was found that the addition of a small amount of Mn effectively reduces the dielectric loss and improves the resistivity of the films. The BMT-0.37PT-0.005Mn film exhibits lower leakage current density than the undoped BMT-0.37PT film such that saturated hysteresis loops can be achieved. As a result, the BMT-0.37PT-0.005Mn film exhibits the largest permittivity (epsilon(r) similar to 1271 at 1 kHz) and remanent polarization (P-r similar to 17.4 mu C/cm(2) at 100 Hz) in all studied compositions. (C) 2012 Elsevier B.V. All rights reserved.