Extractive method of threshold voltage distribution in floating gate NAND flash memory by using the charge pumping technique

In this paper the authors proposed a new method to estimate ¿Vth from floating gate NAND flash memory, using charge pumping method to a cell string. Although any cells in a string are selected, this method could be roughly applied to extract ¿Vth. After P/E cycling, the charge pumping method also estimated ¿Vth with moderate pulse amplitude (in this work, at 4.5 V or 5 V). By using our proposed method, not only it is simply possible to estimate ¿Vth of NAND flash memory, but also measurement time can be reduced so much.