Analysis of Charge Loss Decomposition and Nonlinear Ea in 3-D NAND Flash Memory Using a Neutral Cell-Based Method

Abstract

A charge loss decomposition method using neutral cells has been proposed in 3-D NAND flash memory. The pattern-dependent threshold voltage (VT) equations and E-field acceleration factors are derived to analyze the temperature-dependent behavior of charge loss mechanisms. The program-erase-program (PEP) pattern exhibits the most significant lateral migration of holes (LMH) at 120 °C, while the erase-program-erase (EPE) pattern consistently shows the largest trap-to-band tunneling of electrons (TBE), regardless of retention temperatures. The activation energy (Ea) of the EPE pattern has been extracted, revealing that the nonlinear Ea behavior is primarily caused by TBE.