Semiconductor device and method of manufacturing the same

Abstract

A semiconductor device includes a first substrate, a plurality of cell transistors and a second substrate. The first substrate has a first surface and a second surface opposite to the first surface. The plurality of cell transistors is formed extending on the first surface of the first substrate in a direction. The second substrate has an upper surface making contact with the second surface of the first substrate. Further, the upper surface of the second substrate has a bent structure to apply tensile stresses to the first substrate in the extending direction of the plurality of cell transistors. Thus, tensile stresses may be applied to the first substrate to improve the mobility of carriers in a channel region of the cell transistors.

1 . A method of manufacturing a semiconductor device, the method comprising:
 forming a plurality of cell transistors extending on a first surface of a first substrate in a direction;   preparing a second substrate having a bent upper surface; and   contacting the bent upper surface of the second substrate to a second surface of the first substrate opposite to the first surface to apply tensile stresses to the first substrate in the extending direction of the plurality of cell transistors.   
     
     
         2 . The method of  claim 1 , wherein the plurality of cell transistors are arranged on a fringe substrate having a { 110 } crystal plane in a growing direction of single crystalline silicon to extend in the { 110 } crystal plane. 
     
     
         3 . The method of  claim 1 , wherein the plurality of cell transistors are arranged on a fringe substrate having a { 100 } crystal plane in a growing direction of single crystalline silicon to extend in the { 100 } crystal plane. 
     
     
         4 . The method of  claim 1 , wherein forming of each of the plurality of cell transistors comprises sequentially forming a tunnel oxide layer, a floating gate electrode, a dielectric layer and an upper electrode on the first surface of the first substrate. 
     
     
         5 . The method of  claim 1 , wherein forming of each of the plurality of cell transistors comprises sequentially forming a tunnel oxide layer, a charge trapping layer pattern, a dielectric layer and an upper electrode on the first surface of the first substrate. 
     
     
         6 . The method of  claim 1 , wherein the bent upper surface of the second substrate has a convex shape in a direction substantially the same as the extending direction of the plurality of cell transistors. 
     
     
         7 . The method of  claim 1 , wherein the bent upper surface of the second substrate has a concave shape in a direction substantially perpendicular to the extending direction of the plurality of cell transistors. 
     
     
         8 . The method of  claim 1 , wherein attaching of the first substrate and the second substrate to each other comprises providing an adhesive between the second surface of the first substrate and the bent upper surface of the second substrate. 
     
     
         9 . The method of  claim 8 , wherein the adhesive comprises an epoxy resin.