NON-VOLATILE SEMICONDUCTOR MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To obtain a non-volatile semiconductor memory device which can control a distribution range of a threshold voltage within a narrow range and can improve data retention resistance and read disturbing resistance of memory cell. SOLUTION: A pulse controller 20 outputs a control signal Sp for selecting a pulse voltage Vp to a multiplexer 10 depending the predetermined threshold voltage Vth, moreover produces a control signalϕp for controlling a program pulse width depending on the level of the selected pulse voltage Vp and its inverted signal/ϕp and then outputs these signals to a word line switch 40. The word line switch 40 controls the program pulse width to be impressed to the selected word line with a row decoder 30 depending on these control signals. Therefore, distribution width of the threshold value Vth of the memory cell after the writing operation can be controlled within the narrow range.