Investigation of Reliability and Optimization of Reprogram Process in 3D NAND Flash Memory Based on Physical Model

In this study, we simulate a 3D Bandgap Engineered (BE-TOX) NAND Flash device using the Monte Carlo method. The simulation considers the Incremental Step Pulse Programming (ISPP) and Reprogram Scheme (Re-PGM), which are commonly used in the current industry. Through this research, we first investigate the formation process of the threshold voltage (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{V}_{\text{th}}$</tex>) distribution and analyze it from a physical perspective. Furthermore, we identify the trade-off relationship between reliability and performance. Finally, we propose strategies to optimize the program operation.