Vertical Structure Semiconductor Memory Devices And Methods Of Manufacturing The Same

A semiconductor memory device comprising:

• a substrate extending in a first direction and a second direction substantially perpendicular to the first direction;
• pillar-shaped semiconductor regions extending from the substrate in a third direction, the third direction being substantially perpendicular to the first direction and the second direction, and the pillar-shaped semiconductor regions being separated from each other in the first direction and the second direction;
• a plurality of memory cell strings extending in the third direction along sidewalls of the pillar-shaped semiconductor regions;
• at least one impurity region defined in the substrate between the plurality of memory cell strings and extending in the second direction;
• at least one substrate contact electrode coupled to the at least one impurity region in the substrate;
• and
• a plurality of insulating regions formed as air gaps between the at least one substrate contact electrode and the plurality of memory cell strings.

A semiconductor memory device having a three-dimensional structure, the semiconductor memory device comprising:

• at least one memory cell string disposed on a first region of a surface of a substrate and extending in a first direction, the first direction being substantially perpendicular to the surface of the substrate;
• and
• at least one substrate contact electrode disposed on a second region of the substrate and extending in the first direction;
• wherein
• the substrate contact electrode is insulated from the at least one memory cell string by an air gap.