Improvement of Data Retention in NAND Flash Memory for beyond 3x nm using HTO Liner and IPD Thickness Optimization

Abstract

As cell size shrinks in NAND Flash memory, assuring adequate reliability characteristics is getting difficult due to the sensitivity of Flash cell against small process changes. Especially, it is still unclear how the combination of mechanical stresses encapsulating the cell structure affects the reliability characteristics. In this paper, we present our results on how to improve reliability with optimizing mechanical stress in active and interpoly dielectrics (IPD) thickness, and confirmed the results through various simulations and test methods on 41nm NAND technology. Hereafter, we need to fully confirm the ISO and IPD beyond 3x nm technology node.