Programming method for semiconductor memory device.

摘要

There is disclosed an improvement in a programming method in a semiconductor memory device for injecting electrons into a floating gate (3) and extracting them through a tunnel portion (3a). In acoordance with this programming method, a program voltage is applied across the drain (1) and the control gate (4) of each memory cell from which electrons are extracted, and a voltage having the same polarity as that of the program voltage and an absolute value which is small to such an extent that field inversion can be prevented is applied across the drain (1) and the control gate (4) of each memory cell from which no electron is extracted.