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

Abstract

In this paper the authors proposed a new method to estimate ¿V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> 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 ¿V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> . After P/E cycling, the charge pumping method also estimated ¿V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> 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 ¿V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> of NAND flash memory, but also measurement time can be reduced so much.