Semiconductor device and method for operating the same

Abstract

The semiconductor device includes memory strings, word lines, bit lines and a circuit. The memory strings each include memory cells connected in series. The gate electrode surrounds the channel. The word lines are electrically connected to gate electrodes of memory cells. The bit lines are electrically connected to ends of current paths in the memory strings respectively. The circuit controls a program operation of information. The information includes at least three of a first, a second and a third levels or more corresponding to threshold voltages of the memory cells. When starting the program operation, the circuit applies a program selection voltage to channels of memory cells to be programmed at the second level, and a program suppression voltage to channels of memory cells maintaining the first level and channels of memory cells to be programmed at the third level.