Low voltage operating InGaZnO4 thin film transistors using high-k MgO–Ba0.6Sr0.4TiO3 composite gate dielectric on plastic substrate

Abstract

The authors report on the dielectric and leakage current properties of room temperature grown MgO-Ba0.6Sr0.4TiO3 (MgO-BST) composite thin films to be utilized InGaZnO4 thin films transistors (TFTs) fabricated on a polyethylene terephthalate (PET) substrate. The InGaZnO4 TFTs with MgO-BST gate dielectrics exhibited low operation voltage of 4V, high on/off current ratio of 4.13×106, and high field effect mobility of 10.86cm2∕Vs. These results verify that a room temperature grown MgO-BST gate dielectric is a good candidate for producing high performance InGaZnO4 TFTs on plastic substrates.