Correlation of proton and heavy-ion test results on CMOS bulk memories used for space applications

Experiments were performed to determine the heavy-ion and proton sensitivity of CMOS Bulk 2K×8 RH Space-Qualified SRAMs. The tests were conducted at room temperature and worst-case supply voltage on devices with several different cross-coupled memory cell resistor values. The results indicated correlation between heavy-ion LET threshold versus proton apparent threshold. The heavy-ion data indicate a correlation between the upset cross-sections and resistor values as well. Several proton energies were used to determine energy dependence of proton sensitivity. A special assessment/evaluation of the measured, calculated, and inferred parameter values was performed. The results were used to predict upset rates for a mission-specific space environment