Nonvolatile memory device and memory system including nonvolatile memory device

A nonvolatile memory device includes a memory cell array, an erase body voltage generator, and an erase source voltage generator. The memory cell array includes memory blocks, each of which includes cell strings each including a ground selection transistor, memory cells, and a string selection transistor stacked in a direction perpendicular to a substrate. The erase body voltage generator applies an erase body voltage to the substrate during an erase operation. The erase source voltage generator applies an erase source voltage to a common source line connected with ground selection transistors of the cell strings during the erase operation. 非易失性存储器设备包括存储器单元阵列、擦除体电压发生器、和擦除源电压发生器。存储器单元阵列包括存储器块，存储器块中的每一个存储器块包括单元串，每个单元串包括在垂直于基底的方向上堆叠的地选择晶体管、存储器单元、和串选择晶体管。擦除体电压发生器在擦除操作期间将擦除体电压施加到基底。擦除源电压发生器在擦除操作期间将擦除源电压施加到与单元串的地选择晶体管连接的公共源极线。