Cross-temperature Reliabilities in TLC 3D NAND Flash Memory: Characterization and Solution

Temperature impacts on the reliabilities of TLC 3D NAND flash memory are investigated through crosstemperature measurements, and a simple method is proposed to estimate the optimal read voltage (Vopt) to lower the error bits. With real chip characterizations, it is shown that Vopt is strongly correlated to the temperature difference between data reading and data programming, rather than the temperature itself. This indicates that V-opt can be obtained by using Vth offset between operation temperatures. The effects of the proposed scheme are also evaluated in real chips, showing that similar to 60% error bits can be well suppressed.