Flexible InGaZnO TFTs with Stacked GeO2/TiO2 Gate Dielectrics

Abstract

We reported an amorphous InGaZnO thin-film transistor using stacked gate dielectrics of GeO2/TiO2 on flexible polycarbonate substrate. The flexible TFT showed a low threshold voltage of 2.2 V, small sub-threshold swing of 256 mV/decade, an field effect mobility of 4 cm(2)/Vs, and a good I-on/I-off ratio of 3.7x10(5). The flexible TFT with low operation voltage and high drive current could be attributed to the combined effect of flat plastic substrate, large band-gap GeO2 and higher-kappa TiO2.