Optimization of read operation for low power consumption in 3D NAND flash memory

Abstract

This study proposes a low power read operation to minimize the hot carrier injection (HCI) phenomenon that occurs during read operations in 3D NAND Flash Memory. Owing to the characteristics of the 3D NAND Flash Memory structure, the channels of unselected strings can easily remain in a floating state. This leads to HCI during read operations, resulting in read disturbances. To improve the read disturb characteristics, triangular pulse voltages (V_TP) with adjusted slopes and delayed application times were applied to the string selected line (SSL) and the ground selected line (GSL) during read operations. Using the proposed read scheme, it was confirmed that HCI was decreased compared to the conventional method, and it was possible to operate at low power.