Semiconductor memory device and method for program operation having program loops by step voltage

Abstract

Provided herein are a semiconductor memory device and a method of operating the semiconductor memory device. The semiconductor memory device includes a memory cell array including a memory cell array including a plurality of memory cells, a peripheral circuit configured to perform a program operation, which includes a plurality of program loops, on selected memory cells among the plurality of memory cells and a control circuit configured to control the peripheral circuit so that a program voltage applied to a selected word line, to which the selected memory cells are coupled, is stepwisely increased from a program start voltage to a target program voltage by a step voltage, which is a voltage increment of the program voltage, during a preset time period of a respective program loop.