Vertical nonvolatile memory device including memory cell strings

A nonvolatile memory device comprising:

• a channel layer extending in a first direction;
• a plurality of gate electrodes and a plurality of spacers each extending in a second direction crossing the first direction, the plurality of gate electrodes and the plurality of spacers being alternately arranged with each other in the first direction;
• and
• a gate insulating layer extending in the first direction between the channel layer and the plurality of gate electrodes, wherein
• the gate insulating layer includes a hexagonal boron nitride (h-BN) layer between the channel layer and the plurality of gate electrodes, a charge trap layer between the channel layer and the h-BN layer, and a tunneling dielectric layer between the channel layer and the charge trap layer.

A nonvolatile memory device comprising:

• a channel layer extending in a first direction;
• a plurality of gate electrodes each extending in a second direction crossing the first direction, the plurality of gate electrodes spaced apart from each other in the first direction along a sidewall of the channel layer;
• and
• a gate insulating layer between the channel layer and the plurality of gate electrodes,
• wherein each of the plurality of gate electrodes includes a metal-doped graphene.