Semiconductor device and manufacturing method of a semiconductor device

Abstract

A semiconductor device includes a stack structure including conductive patterns spaced apart from each other, a channel structure penetrating the stack structure, and a slit insulating layer penetrating the stack structure. Air gaps are defined between the conductive patterns. The slit insulating layer includes a first interposition part covering a sidewall of one of the conductive patterns and a second interposition part covering one of the air gaps from the side. A smallest width of the second interposition part is smaller than a smallest width of the first interposition part.

What is claimed is: 
     
         1 . A method of manufacturing a semiconductor device, the method comprising:
 forming a stack structure including alternately stacked insulating layers and sacrificial layers;   forming a trench penetrating the stack structure;   replacing the sacrificial layers with conductive patterns;   forming buffer patterns on sidewalls of the conductive patterns;   forming air gaps by removing the insulating layers; and   forming a slit insulating layer sealing the air gaps,   wherein forming the slit insulating layer includes oxidizing the buffer patterns.   
     
     
         2 . The method of  claim 1 , wherein forming the slit insulating layer includes:
 forming a first insulating part by oxidizing the buffer patterns; and   depositing a second insulating part on the first insulating part.   
     
     
         3 . The method of  claim 1 , wherein forming the buffer patterns includes:
 forming oxidation patterns on sidewalls of the insulating layers; and   forming the buffer patterns between the oxidation patterns.   
     
     
         4 . The method of  claim 3 , wherein forming the oxidation patterns includes selectively depositing the oxidation patterns on the sidewalls of the insulating layers. 
     
     
         5 . The method of  claim 3 , wherein forming the oxidation patterns includes:
 forming first recesses by removing a portion of each of the insulating layers through the trench;   forming seed patterns in the first recesses;   forming preliminary oxidation patterns on sidewalls of the seed patterns; and   oxidizing the seed patterns and the preliminary oxidation patterns.   
     
     
         6 . The method of  claim 5 , wherein the preliminary oxidation patterns are selectively formed on the sidewalls of the seed patterns. 
     
     
         7 . The method of  claim 1 , further comprising:
 forming a hole penetrating the stack structure;   forming recesses by removing a portion of each of the insulating layers through the hole;   forming protective patterns in the recesses; and   forming a memory layer in the hole,   wherein removing the insulating layers includes exposing the protective patterns.   
     
     
         8 . The method of  claim 1 , further comprising:
 forming a hole penetrating the stack structure;   forming recesses by removing a portion of each of the insulating layers through the hole;   forming a protective layer in the hole and the recesses; and   forming a memory layer in the hole,   wherein removing the insulating layers includes removing a portion of the protective layer.   
     
     
         9 . The method of  claim 1 , wherein forming the buffer patterns includes forming the buffer patterns between the insulating layers. 
     
     
         10 . The method of  claim 1 , wherein the buffer patterns include poly-silicon. 
     
     
         11 . The method of  claim 1 , wherein the buffer patterns include nitride.