Thin film transistor and method of manufacturing same

Abstract

A thin film transistor can include a substrate, a gate electrode on the substrate, a first electrode located on the substrate and surrounded by the gate electrode, a second electrode located on the first electrode and surrounded by the gate electrode, and a channel layer located between the first electrode and the second electrode. The gate electrode can include a first margin metal layer on the substrate and a second metal layer located on the first margin metal layer. A method for manufacturing the thin film transistor is also provided.

What is claimed is: 
     
         1 . A thin film transistor comprising:
 a substrate;   a gate electrode, the gate electrode formed on the substrate and comprising a first margin metal layer formed on the substrate and a second metal layer located on the first margin metal layer;   a first electrode, the first electrode located on the substrate and surrounded by the gate electrode;   a second electrode, the second electrode located on the first electrode and surrounded by the gate electrode; and   a channel layer, the channel layer located between the first electrode and the second electrode and surrounded by the gate electrode.   
     
     
         2 . The thin film transistor of  claim 1 , wherein the gate electrode is spaced apart from the first electrode, the second electrode, and the channel layer. 
     
     
         3 . The thin film transistor of  claim 2  further comprising an electrically insulating layer formed on the substrate and covering the gate electrode and the second electrode, wherein the electrically insulating layer makes the gate electrode electrically insulated from the first electrode, the second electrode and the channel layer. 
     
     
         4 . The thin film transistor of  claim 3 , wherein the electrically insulating layer is filled in a gap between the gate electrode and a combination of the first electrode, the second electrode, and the channel layer. 
     
     
         5 . The thin film transistor of  claim 1 , wherein the first electrode is a source electrode of the thin film transistor, and the second electrode is a drain electrode of the thin film transistor. 
     
     
         6 . The thin film transistor of  claim 1 , wherein the first margin metal layer and the first electrode are defined by a same conductive layer. 
     
     
         7 . The thin film transistor of  claim 6 , wherein the the first margin metal layer and the first electrode is made of titanium. 
     
     
         8 . The thin film transistor of  claim 1 , wherein the second margin metal layer is made of a material different from that of the second electrode. 
     
     
         9 . The thin film transistor of  claim 8 , wherein the second margin metal layer is made of aluminum, and the second electrode is made of copper. 
     
     
         10 . The thin film transistor of  claim 1 , wherein the first electrode and the second electrode are coupled to the channel layer in electrical conduction.