Semiconductor device and manufacturing method of semiconductor device

A semiconductor device comprising:

• a well structure including a well dopant;
• a gate stack structure comprising a first stack structure, a second stack structure, and a third stack structure, which are continuously stacked in a first direction over the well structure, the gate stack structure comprising a groove formed in a sidewall of the gate stack structure, wherein the groove is defined between the first stack structure and the third stack structure, and wherein the first stack structure and the third stack structure protrude farther than the second stack structure in a second direction perpendicular to the first direction;
• a channel pattern penetrating the gate stack structure, the channel pattern extending along a surface of a horizontal space between the well structure and the gate stack structure;
• a memory pattern extending along an outer wall of the channel pattern;
• a spacer insulating pattern formed on the sidewall of the gate stack structure;
• and
• a doped semiconductor pattern formed on the spacer insulating pattern, the doped semiconductor pattern extending toward the horizontal space to contact the channel pattern, the doped semiconductor pattern comprising a source dopant.