Color emission and dielectric properties of Eu-doped Gd2O3 gate oxide thin films

Abstract

High-k Gd2O3 used for thin film transistor (TFT) gate insulators has been synthesized via a simple solution process. Phase analysis and capacitive performance reveal that a high dielectric constant of similar to 20 and a low leakage current level of <10(-8) A/cm(2) at 1 MV/cm with a good transparency under the visible wavelength region are readily produced by the sol-gel method. Eu3+ doping leads to an increased dielectric constant induced by the additional electric dipole transition, which is evidently visualized by the photoluminescence behavior and/or by the defect-controlled thin film microstructures. Thus, the solution-processed (Gd,Eu)(2)O-3 film is a viable gate insulator to be considered for the proposed "color emissive" switching devices as well as for the low power-driven TFT devices. (C) 2010 Elsevier B.V. All rights reserved.