Electric Field Impact on Lateral Charge Diffusivity in Charge Trapping 3D NAND Flash Memory

We propose a novel method of predicting electron and hole lateral diffusion in a charge trapping layer (CTL) of 3D TLC NAND, which can estimate the long-term lateral migration (LM) behavior in a short time. By monitoring the threshold voltage change (△Vth) of the select cell under various bias and temperature conditions, we observe that electron and hole lateral diffusivity matches well with the Poole-Frenkel (PF) model. The lateral diffusivity is extracted by measuring △Vth when the electrons and holes of neighboring cells reach the selected cell. by accelerating the diffusivity up to 10.35 times with biasing 3V to neighbor cell, the measurement time required for forecasting the long-term LM becomes 94% shorter with <5.5% error.