Proton direct ionization upsets at tens of MeV

Experimental mono-energetic proton single-event upset (SEU) cross-sections of a 65 nm low core-voltage static random access memory (SRAM) were found to be exceptionally high not only at energies (< 3 MeV), but also > MeV and extending up tens MeV. The SEU cross-section from 20 protons exceed the 200 by almost factor 3. Similarly, neutron 14 are about lower than cross-section. Thanks Monte-Carlo (MC) simulations it was determined that this strong enhancement is due direct ionization process as opposed elastic inelastic scattering processes dominate response above in other SRAMs. As shown means detailed energy deposition scoring analysis, however, does appear caused critical charge SRAM being resulting average through linear transfer (LET). On hand, high-energy δ-rays (> 1 keV) can deposit their full kinetic within sensitive volume (SV) cell despite range theoretically much longer characteristic size SV. Multiple events responsible for increasing trajectory path volume, 6 fold increase probability with respect sole electron ionization.