Semiconductor device with recess gate and method for fabricating the same

Abstract

A semiconductor device includes a substrate with a recess pattern, a gate electrode filling the recess pattern, a threshold voltage adjusting layer formed in the substrate under the recess pattern, a source/drain region formed in the substrate on both sides of the gate electrode and a gate insulation layer, with the recess pattern being disposed between the gate electrode and the substrate, wherein the thickness of the gate insulation layer formed in a region adjacent to the source/drain region is greater than the thickness of the gate insulation layer formed in a region adjacent to the threshold voltage adjusting layer.

1 . A semiconductor device, comprising:
 a substrate with a recess pattern;   a gate electrode filling the recess pattern;   a threshold voltage adjusting layer formed in the substrate under the recess pattern;   a source/drain region formed in the substrate on both sides of the gate electrode; and   a gate insulation layer, with the recess pattern being disposed between the gate electrode and the substrate, wherein the thickness of the gate insulation layer formed in a region adjacent to the source/drain region is greater than the thickness of the gate insulation layer formed in a region adjacent to the threshold voltage adjusting layer.   
     
     
         2 . The semiconductor device of  claim 1 , wherein the thickness of the gate insulation layer formed in the region adjacent to the threshold voltage adjusting layer is in a range of approximately 70% to approximately 80% of the thickness of the gate insulation layer formed in the region adjacent to the source/drain region. 
     
     
         3 . The semiconductor device of  claim 1 , wherein the gate electrode has a structure filling a portion of the recess pattern, or a structure filling the recess pattern and partially protruding over the substrate. 
     
     
         4 . The semiconductor device of  claim 1 , wherein the recess pattern is any one type selected from the group consisting of a square type, a polygonal type, a bulb type, and a saddle fin type. 
     
     
         5 - 20 . (canceled)