Semiconductor memory device and operating method thereof

Abstract

Provided are a semiconductor memory device and an operating method thereof. The semiconductor memory device may include a memory cell array having a plurality of strings each including a drain select transistor, a plurality of drain side memory cells, a pipe transistor, a plurality of source side memory cells, and a source select transistor. The semiconductor memory device may also include a peripheral circuit suitable for providing a plurality of operation voltages including an erase verify voltage to the plurality of strings, and a control logic suitable for controlling the peripheral circuit to adjust a voltage level of the erase verify voltage applied to a selected memory cell, from among the plurality of drain side memory cells and the plurality of source side memory cells, according to a distance between the selected memory cell and the pipe transistor when an erase verify operation is performed.