Semiconductor device with contact structure and manufacturing method thereof

Abstract

A plurality of gate lines are formed on a substrate. After depositing a gate insulating layer, a semiconductor layer and a doped amorphous silicon layer are sequentially formed thereon. A lower insulating layer made of silicon nitride and an upper insulating layer made of a photosensitive organic material are deposited thereon after forming data lines and drain electrodes. The upper insulating layer is patterned to form an unevenness pattern on its surface and contact holes on the drain electrodes. The lower insulating layer is patterned together with the gate insulating layer using a photoresist pattern having apertures located in the contact holes to form other contact holes respectively exposing the drain electrodes, portions of the gate lines, and portions of the data lines. After forming transparent electrodes and contact assistants respectively connected to the drain electrodes and the gate and the data lines through the contact holes, reflecting electrodes having apertures are formed on the transparent electrodes.

1 . A semiconductor device, comprising: 
 a substrate;    a first conductor formed on the substrate;    a first insulating layer formed on the first conductor and having a first contact hole exposing at least a portion of the first conductor;    a second insulating layer formed on the first insulating layer and having a second contact hole exposing the first conductor along with the first contact hole, a unity of the first and the second contact holes having a height-dependent width; and    a second conductor formed on the second insulating layer and connected to the first conductor through the first and the second contact holes.    
   
   
       2 . The semiconductor device of  claim 1 , wherein the width of the unity of the first and the second contact holes at a higher position of the unity is wider than at a lower position of the unity.  
   
   
       3 . The semiconductor device of  claim 2 , wherein the unity of the first and the second contact holes has a stepwise sidewall.  
   
   
       4 . The semiconductor device of  claim 3 , wherein the second contact hole is larger than the first contact hole.  
   
   
       5 . The semiconductor device of  claim 3 , wherein the first contact hole exposes a surface of the first insulating layer.  
   
   
       6 . The semiconductor device of  claim 5 , wherein the width of the exposed surface of the first insulating layer is equal to or larger than 0.1 microns.  
   
   
       7 . The semiconductor device of  claim 1 , wherein the second insulating layer comprises an organic insulating material.  
   
   
       8 . The semiconductor device of  claim 1 , wherein sidewalls of the first and the second contact holes are tapered and have different inclination angles.  
   
   
       9 . The semiconductor device of  claim 8 , wherein the inclination angle of the sidewall of the first contact hole is larger than the inclination angle of the sidewall of the second contact hole.