Semiconductor device and manufacturing method thereof

A method of manufacturing a semiconductor device, the method comprising:

• forming a conductive layer including line regions and etching regions alternately disposed with each other;
• forming first channel structures passing through the conductive layer in the line regions and protruding farther than the conductive layer;
• forming insulating patterns filling a first distance defined between the first channel structures in each of the line regions after forming the first channel structures, wherein each of the insulating patterns covers a top surface of the conductive layer;
• and
• removing the etching regions of the conductive layer which are exposed between the insulating patterns to divide the conductive layer into line patterns.