Non-volatile memory device including etch stop layer pattern

A non-volatile memory device comprising:

• a substrate including a common source region and a common source line strapping region,
• the common source line strapping region crossing the common source region;
• channel regions extending in a vertical direction on the substrate;
• gate electrodes separated from each other in the vertical direction and a horizontal direction along outer walls of the channel regions;
• a first insulating interlayer on the gate electrodes and the channel regions,
• the first insulating interlayer defining a contact hole that exposes a portion of the common source line strapping region between at least one adjacent pair of the gate electrodes;
• a contact plug in the contact hole,
• the contact plug electrically connected to the common source line strapping region;
• an etch stop layer pattern on the contact plug,
• the etch stop layer pattern contacting a part of the first insulating interlayer;
• and
• a second insulating interlayer on the first insulating interlayer and the etch stop layer pattern.

A non-volatile memory device comprising:

• a substrate including a common source line strapping region intersecting at least one common source region;
• a plurality of memory strings extending vertically on the substrate;
• a contact plug between at least two of the plurality of memory strings,
• the contact plug on the common source line strapping region;
• a first insulating interlayer on the plurality of memory strings,
• the first insulating interlayer defining a contact hole that exposes the contact plug;
• and
• an etch stop layer pattern in the contact hole and on the contact plug.