Memory device including vertical channel structure

Abstract

Provided is a memory device with a vertical channel structure. The memory device includes a memory cell array including a plurality of memory cells and a plurality of string selection lines, a negative charge pump configured to generate a bias voltage of a negative level, to be applied to at least one of the plurality of string selection lines, and a control logic circuit configured to apply, for a first period, a prepulse voltage to at least one unselected string selection line among the plurality of string selection lines excluding a selected string selection line to which a memory cell selected from among the plurality of memory cells is connected and thereafter apply the bias voltage to the at least one unselected string selection line so as to perform a read operation on the selected memory cell.