Comparison of Soft Errors Induced by Heavy Ions and Protons

Careful measurements of the SEU cross section versus the LET of the incident heavy ion were carried out on a single Intel 64K dRAM for which proton SEU data had been recently obtained in order to test whether a single set of modeling assumptions could provide fits to both data sets. The Intel 2164A 64k dRAM exhibited consistent cross-section measurements among devices tested, a high total-dose tolerance, and a proton SEU cross section that was unaffected by accumulated dose, making the device very suited for extended radiation studies. The heavy-ion cross section versus LET data was used as input to the CUPID code predictions of the proton-upset cross section versus incident proton energy. Observed agreement is consistent with the hypothesis that proton-induced upsets, even in alpha sensitive devices, are the result of recoiling nuclear fragments from inelastic nuclear interactions and the same basic mechanism is reponsible for both heavy ion and proton-induced upsets.