Semiconductor device including gate pattern having pad region

Abstract

A semiconductor device includes a gate pattern disposed over a lower structure, and including a gate electrode region and a gate pad region extending from the gate electrode region; and a vertical channel semiconductor layer having a side surface facing the gate electrode region of the gate pattern. The gate pad region includes a first pad region having a thickness greater than a thickness of the gate electrode region. The first pad region includes an upper surface, a lower surface opposing the upper surface, and an outer side surface. The outer side surface has a lower outer side surface and an upper outer side surface, divided from each other by a boundary portion. The lower outer side surface extends from the lower surface, and a connection portion of the lower outer side surface and the lower surface has a rounded shape.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a gate pattern disposed over a lower structure, and including a gate electrode region and a gate pad region extending from the gate electrode region; and   a vertical channel semiconductor layer having a side surface facing the gate electrode region of the gate pattern,   wherein the gate pad region includes a first pad region having a thickness greater than a thickness of the gate electrode region,   the first pad region includes an upper surface, a lower surface opposing the upper surface, and an outer side surface,   the outer side surface has a lower outer side surface and an upper outer side surface, divided from each other by a boundary portion, and   the lower outer side surface extends from the lower surface in a rounded shape,   wherein the lower outer side surface has a convex shape, and   wherein the lower outer side surface protrudes further in a lateral direction than the upper outer side surface.   
     
     
         2 . The semiconductor device according to  claim 1 , wherein the lower outer side surface has a convex shape, and wherein a connection portion of the lower outer side surface and the lower surface has a rounded shape. 
     
     
         3 . The semiconductor device according to  claim 2 , wherein the upper outer side surface has a convex shape and extends from the upper surface, and a connection portion of the upper outer side surface and the upper surface has a rounded shape, and
 the boundary portion of the outer side surface is a concave portion formed by connecting the lower outer side surface having the convex shape and the upper outer side surface having the convex shape.   
     
     
         4 . The semiconductor device according to  claim 2 , wherein at least a portion of the upper outer side surface has a concave shape, and
 the boundary portion of the outer side surface is an inflection portion at a connection portion of the lower outer side surface having the convex shape and the portion of the upper outer side surface having the concave shape.   
     
     
         5 . The semiconductor device according to  claim 2 , wherein the upper outer side surface comprises:
 a first upper outer side surface extending at an obtuse angle with respect to the upper surface; and   a second upper outer side surface extending from the first upper outer side surface with a slope different than a slope of the first upper outer side surface.   
     
     
         6 . The semiconductor device according to  claim 1 , wherein the gate pad region further includes a second pad region between the first pad region and the gate electrode region, and
 the second pad region includes a portion having a thickness smaller than the thickness of the gate electrode region.   
     
     
         7 . The semiconductor device according to  claim 1 , wherein a relatively lower portion of the lower outer side surface protrudes further in a lateral direction than a relatively upper portion of the lower outer side surface. 
     
     
         8 . The semiconductor device according to  claim 1 , wherein the lower outer side surface protrudes further in a lateral direction than the upper outer side surface. 
     
     
         9 . A semiconductor device comprising:
 a first gate pattern over a lower structure;   a second gate pattern over the first gate pattern;   an interlayer insulation layer between the first gate pattern and the second gate pattern; and   a contact plug on the first gate patter pattern,   wherein the first gate pattern includes a gate electrode region overlapping with the second gate pattern in a vertical direction, and a gate pad region extending from the gate electrode region, the gate pad region includes a first pad region having a thickness greater than a thickness of the gate electrode region,   wherein the first pad region includes a lower region and an upper region on the lower   wherein the lower region protrudes further in a lateral direction than the upper region,   wherein the lateral direction is a direction from the gate electrode region toward the gate pad region,    wherein the first pad region includes a lower region and an upper region on the lower region,   wherein the lower region includes a lower outer side surface having a convex shape,   wherein the contact plug is in contact with the gate pad region of the first gate pattern and is spaced apart from the second gate pattern, and   wherein a width of the first pad region of the gate pad region is greater than a width of the contact plug.   
     
     
         10 . The semiconductor device according to  claim 9 , wherein the first and second gate patterns protrude further than the interlayer insulation layer in a direction parallel to an upper surface of the lower structure. 
     
     
         11 . The semiconductor device according to  claim 9 , wherein the second gate pattern has a lower surface and an outer side surface extending from the lower surface, and a connection portion of the lower surface and the outer side surface has a rounded shape. 
     
     
         12 . The semiconductor device according to  claim 9 , wherein the upper region includes an upper outer side surface, and
 the first pad region includes a boundary portion, which divides the lower outer side surface of the lower region and the upper outer side surface of the upper region.   
     
     
         13 . The semiconductor device according to  claim 12 , wherein a thickness of the lower region is greater than a thickness of the upper region. 
     
     
         14 . The semiconductor device according to  claim 12 , wherein the upper region includes a first upper region, and a second upper region between the first upper region and the lower region,
 the upper outer side surface includes a first upper outer side surface of the first upper region, and a second upper outer side surface of the second upper region, and   the first upper outer side surface and the second upper outer side surface have different shapes.   
     
     
         15 . The semiconductor device according to  claim 12 , wherein the upper region includes a raised side surface opposing the upper outer side surface, and
 wherein the raised side surface includes a first raised side surface extending from an upper surface of the upper region and forming an obtuse angle with the upper surface of the upper region, and a second raised side surface extending from the first raised side surface and having a more acute slope than the first raised side surface.   
     
     
         16 . A semiconductor device comprising:
 a lower structure;   gate patterns spaced apart from each other in a direction perpendicular to an upper surface of the lower structure, the gate patterns including intermediate gate patterns, a lower gate pattern in a position lower than a position of the intermediate gate patterns, and an upper gate pattern over the intermediate gate patterns; and   a vertical channel semiconductor layer having a side surface facing the upper gate pattern, the intermediate gate patterns and the lower gate pattern,   wherein each of the intermediate gate patterns includes a an intermediate gate electrode region overlapping with a gate pattern from among the gate patterns positioned at a relatively upper portion, and a an intermediate gate pad region extending from the intermediate gate electrode region,   the intermediate gate pad region includes a first intermediate pad region, and a second intermediate pad region between the intermediate gate electrode region and the first intermediate pad region,   the first intermediate pad region has a thickness greater than a thickness of the intermediate gate electrode region and a thickness of the intermediate second intermediate pad region,   the first intermediate pad region includes a lower outer side surface, an upper outer side surface, and a boundary portion between the upper outer side surface and the lower outer side surface, and   a connection portion of a bottom surface of the first intermediate pad region and the lower outer side surface of the first intermediate pad region has a rounded shape,   the lower outer side surface of the first intermediate pad region protrudes further in a lateral direction than the upper outer side surface of the first intermediate pad region,   the lower outer side surface has a convex shape, and   the lateral direction is a direction from the intermediate gate electrode region toward the intermediate gate pad region.   
     
     
         17 . The semiconductor device according to  claim 16 ,
 wherein the intermediate gate patterns include a first gate pattern, a second gate pattern over the first gate pattern, and one or more third gate patterns over the first gate pattern and in a position lower than a position of the second gate pattern,   the intermediate gate pad region of each of the first and second gate patterns extends from the intermediate gate electrode region in a first horizontal direction, and   outer side surfaces of the one or more third gate patterns positioned in the first horizontal direction extend from lower surfaces of the one or more third gate patterns in a rounded shape.   
     
     
         18 . The semiconductor device according to  claim 17 , wherein relatively lower portions of the outer side surfaces of the one or more third gate patterns protrude further in athe lateral direction than relatively upper portions of the outer side surfaces of the one or more third gate patterns. 
     
     
         19 . The semiconductor device according to  claim 16 , wherein the lower gate patternspattern further includeincludes a lower gate pattern in a position lower than a position ofelectrode region overlapping the intermediate gate patterns, and a lower gate pad region extending from the lower gate electrode region in the lateral direction, and  awherein the connection portion of the bottom surface of the first intermediate pad region and the lower outer side surface of the first intermediate pad region has a more rounded shape than a connection portion of a lower surface of the lower gate pad region of the lower gate pattern and an outer side surface of the lower gate pad region of the lower gate pattern.   
     
     
         20 . The semiconductor device according to  claim 19 , wherein the gate patterns further include an upper gate pattern over the intermediate gate patterns, and a connection portion of a lower surface of the upper gate pattern and an outer side surface of the upper gate pattern has a more rounded shape than the connection portion of the lower surface of the lower gate pad region of the lower gate pattern and the outer side surface of the lower gate pad region of the lower gate pattern. 
     
     
       21. The semiconductor device according to  claim 1 , further comprising a void in the first pad region,
 wherein a lower end of the void is at a lower level than the boundary portion.    
     
     
       22. The semiconductor device according to  claim 13 , further comprising a void in the lower region of the first pad region.  
     
     
       23. The semiconductor device according to  claim 12 , wherein the contact plug contacts the first pad region of the gate pad region, and
 wherein a lower surface of the contact plug is at a lower level than the boundary portion of the first pad region.    
     
     
       24. The semiconductor device according to  claim 12 ,
 wherein a thickness of the upper region is greater than a thickness of the lower region,   wherein the gate pad region further includes a second pad region between the first pad region and the gate electrode region,   wherein the second pad region include a portion having a thickness smaller than the thickness of the gate electrode region,   wherein the second pad region does not overlap with the second gate pattern in the vertical direction,   wherein the contact plug contacts the first pad region of the gate pad region,   wherein a lower surface of the contact plug is at a lower level than an upper surface of the first pad region, and   wherein the lower surface of the contact plug is at a higher level than a lower surface of the first pad region.    
     
     
       25. The semiconductor device according to  claim 24 , wherein a lower surface of the contact plug is at a higher level than the boundary portion of the first pad region.  
     
     
       26. The semiconductor device according to  claim 16 , further comprising a void in the first intermediate pad region,
 wherein at least a portion of the void is at a lower level than the boundary portion.    
     
     
       27. The semiconductor device according to  claim 16 ,
 wherein the lower gate pattern includes a lower gate electrode region overlapping the intermediate gate patterns, and a lower gate pad region extending from the lower gate electrode region in the lateral direction,   wherein a thickness of the lower gate pad region is substantially the same as a thickness of the lower gate electrode region, and   wherein the thickness of the lower gate pad region is smaller than the thickness of the first intermediate pad region.    
     
     
       28. The semiconductor device according to  claim 27 ,
 wherein the upper gate pattern includes an upper gate electrode region, and an upper gate pad region extending from the upper gate electrode region in the lateral direction,   wherein a thickness of the upper gate pad region is substantially the same as a thickness of the upper gate electrode region, and   wherein the thickness of the upper gate pad region is smaller than the thickness of the first intermediate pad region.    
     
     
       29. The semiconductor device according to  claim 28 , further comprising contact plugs,
 wherein the contact plugs include:
 a lower contact plug contacting the lower gate pad region of the lower gate pattern; 
 intermediate contact plugs contacting intermediate gate pad regions of the intermediate gate patterns; and 
 an upper contact plug contacting the upper gate pad region of the upper gate pattern.  
   
     
     
       30. The semiconductor device according to  claim 16 ,
 wherein the lower structure includes:
 a first substrate; 
 a peripheral circuit structure on the first substrate; and 
 a second substrate on the first substrate.