Significantly reduced leakage currents in organic thin film transistors with Mn-doped Bi2Ti2O7 high-k gate dielectrics

We report the fabrication of organic thin-film transistors (OTFTs) with high-k gate dielectrics of Mn-doped Bi2Ti2O7 (BTO) films. 3% Mn-doped BTO films deposited on polymer substrates by pulsed laser deposition at room temperature exhibit low leakage currents of 2.1 x 10(8) A/cm2 at an applied electric field of 0.3 MV/cm, while undoped BTO films show much higher leakage currents of 4.3 x 10(4) A/cm2. Mn doping effectively reduces the number of oxygen vacancies in the films and improves the electrical properties. Low operation voltage and significantly reduced leakage currents are demonstrated in pentacene-based OTFTs with the Mn-doped BTO gate dielectrics. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim