Method of fabricating CMOS thin film transistor

Abstract

A method of fabricating a CMOS thin film transistor. First and second active layers are formed at first and second transistor areas of a transparent substrate. A gate insulating film is formed at middle portions of the first and second active layers while the sides of each are exposed. Each exposed side is ion-doped with a first conductive impurity at a first energy and at a first concentration using the first and second gate electrodes as mask, thus forming first and second high-concentrated areas. A photoresist pattern that covers the first transistor area is formed on the transparent substrate. The second high-concentrated impurity area is ion-doped with a second conductive impurity, at a second energy that is greater than the first energy and at a second concentration that is greater than the first concentration, to form a third high-concentrated impurity area that is counter-doped.

1 - 16 . (canceled)  
     
     
         17 . A CMOS thin film transistor, comprising: 
 a first active layer on a substrate, said first active layer having end portions that are ion-doped with a first conductive impurity of a first polarity;    a first gate insulating film on a middle portion of said first active layer;    a second active layer on said substrate, said second active layer having end portions that are ion-doped with said first conductive impurity and with a second conductive impurity of an opposite polarity, wherein said second conductive impurity changes the doping of said end portions from said first polarity to said second polarity;    a second gate insulating film on a middle portion of said second active layer;    a first gate over said first gate insulating film; and    a second gate over said second gate insulation film.    
     
     
         18 . The CMOS thin film transistor according to  claim 17 , wherein said first conductive impurity is a p-type impurity.  
     
     
         19 . The CMOS thin film transistor according to  claim 17 , wherein said substrate is transparent.  
     
     
         20 . The CMOS thin film transistor according to  claim 17 , further including an insulating layer between said first active layer and said substrate.