Impact of Neutron-Induced Displacement Damage on the Multiple Bit Upset Sensitivity of a Bulk CMOS SRAM

Neutron irradiation of a multiple bit upset sensitive bulk CMOS SRAM prior to heavy ion exposure is shown to significantly increase the number of bits upset per event observed. The displacement damage induced by the neutron exposure prior to the single event experiment is shown to have little to no impact on the performance of the SRAM. However, the neutron fluence is able to induce small changes in the resistivity of the underlying silicon of the SRAM which leads to a large change in the multiple bit upset response. From the results of this experiment, critical insight into the mechanisms behind multiple bit upsets in bulk CMOS technologies is gained.