Temperature-induced Instability of Retention Characteristics in 3-D NAND Flash Memory

A temperature-induced instability of retention characteristics is observed in 3-D NAND flash. The effect of grain boundary (GB) is newly considered to investigate the retention characteristics at different program temperature $(T_{PGM})$ and read temperature $(T_{READ})$. At high $T_{PGM}$, the decrease of threshold voltage $(V_{T})$ is reduced. As the difference between $T_{PGM}$ and $T_{READ}$ increases, VT change after 4 h varies linearly from negative to positive value due to the increase of the GB effect.