Electron Irradiation of Samsung 8-Gb NAND Flash Memory

This paper reports the results of electron irradiations at various energies of the Samsung 8-Gb single-level cell nand flash memory. The percentage of bit errors from electron exposure is compared to results from
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Co total ionizing dose (TID) measurements. Electron irradiation at low energies (below 2 MeV) causes more bit upsets than
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Co gamma exposures at the same TID level when TID refers to equilibrium dose (as opposed to local dose). Bit upsets increase when electron energy decreases if comparisons are made at the same equilibrium dose level. In particular, 60-MeV electrons are less damaging than
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Co gamma exposures at the same equilibrium dose level while 1-MeV electrons are more damaging. However, all radiation sources produce virtually identical results when comparisons are made at the same local dose level, indicating that charged-particle equilibrium is violated during electron irradiations.