Radiation Tolerance of Nanocrystal-Based Flash Memory Arrays Against Heavy Ion Irradiation

We present new results on heavy-ion irradiation of nanocrystal non-volatile addressable memory arrays. We show that the effects of a single ion hit are negligible on these devices due to the discrete nature of the storage sites. We estimate that, in order to observe an appreciable threshold voltage shift, at least three-four ion hit are needed. Despite several cells experienced multiple hits they are still functional after the irradiation, showing no changes on the retention characteristics. These results highlights an outstanding improvement of the nanocrystal technology over the conventional floating gate memories in terms of radiation tolerance, which are encouraging for a potential application in radiation-harsh environments.