A new data retention mechanism after endurance stress on flash memory

We propose a new data retention model after endurance stress that may be explained as a combination of two retention mechanisms. One inherent retention characteristic is ruled by thermionic emission and is dominant above 150 C. The other retention mechanism is dominant below 85 to 125 C and is controlled by anomalous SILC. We have clarified that the data retention properties after P/E cycling were well fitted by the hopping conduction model. In particular, the presence of traps generated by excessive P/E cycling played a significant role in the temperature dependence of the retention lifetime.

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