Experimental and Theoretical Study of Single Event Latchup in a 3D TLC NAND Flash Memory Under Heavy Ion Irradiation

As a key solid-state mass storage technology for space applications, the reliability of 3D NAND flash memory is susceptible to significant impacts from complex irradiation environments. Focusing on the Single Event Latchup (SEL) effect induced by heavy ion irradiation, this study systematically evaluates its impact on the reliability parameters of 3D NAND flash memory, including read disturb (RD), degradation from program/erase (P/E) cycles, and data retention characterization through measurement and simulation. The results of the experiment showed that the raw bit error rate (RBER) of the RD cycle of the flash memory improves by up to 30.4% under the irradiation effect for different PE cycles conditions. The irradiation effect improves the downshift error in all states, while increases the fail bit count (FBC) in the lower states. In addition, it is shown that the SEL effect can lead to the improvement of up to 21.9% in the data retention characteristics of the memory. The irradiation effect reduces the threshold voltage offset by 27.7% at the simulation level. Our findings provide a useful reference for improving the reliability design and radiation-tolerant 3D NAND flash memory in radiation environments.