Vertical nonvolatile memory device including memory cell string

A neuromorphic apparatus comprising:

• a nonvolatile memory device;
• and
• a processing circuitry configured to control the neuromorphic apparatus based on data stored in the nonvolatile memory device,
• wherein the nonvolatile memory device comprises:
• a plurality of insulating spacers each extending in a first direction,
• a plurality of gate electrodes each extending in the first direction and alternately arranged with the plurality of insulating spacers in a second direction perpendicular to the first direction, and
• a plurality of contacts respectively arranged to contact a side surface of the plurality of gate electrodes respectively corresponding to the plurality of contacts,
• wherein each of the plurality of gate electrodes comprises a conductive two-dimensional material layer and a metal material doped in the conductive two-dimensional material layer.