Oxide thin film transistor and method of fabricating the same

Abstract

An oxide thin film transistor (TFT) and a fabrication method thereof are provided. The method for fabricating an oxide thin film transistor (TFT) comprises: forming a gate electrode on a substrate; forming a gate insulating layer on the substrate with the gate electrode formed thereon; forming an active layer made of oxide semiconductor on the gate insulating layer; forming a contact layer on the substrate with the active layer formed thereon and forming source and drain electrodes, which are electrically connected with source and drain regions of the active layer through the contact layer, on the contact layer; forming a protective layer on the substrate with the source and drain electrodes formed thereon; forming a contact hole by removing the protective layer to expose the drain electrode; and forming a pixel electrode electrically connected with the drain electrode through the contact hole, wherein the contact layer is made of oxide including a different metal or conductivity with that of the source and drain electrodes, to adjust a threshold voltage according to the difference in a work function.