Method of achieving narrow V.sub.T distribution after erase in flash EEPROM

摘要

There is provided a method of correcting overerased memory cells in a flash EEPROM memory cell after erase so as to produce a narrow threshold voltage distribution width. A ground potential is applied to all of the sources and substrates of the cells in the array of memory cells. First positive pulse voltages are simultaneously applied to each word line in a first timed sequence on a word line by word line basis. A second positive pulse voltage is simultaneously applied to each bit line in a second timed sequence in a bit line by bit line basis when the first positive pulse voltages are being applied to a first word line and is then repeated for each subsequent word line until a last word line is applied.