Heavy Ion Bit Response and Analysis of 256 Megabit Non-Volatile Spin-Torque-Transfer Magnetoresistive Random Access Memory (STT-MRAM)

Heavy-ion testing was performed recently on 256 Mb STT-MRAMs as a function of fluence and LET for Ne, Ar, Kr, and Au heavy ions. Zero hard-errors were observed in STT-MRAM (Spin-Torque-Transfer Magneto-resistive Random Access Memory) bits in this first-known heavy-ion testing of STT-MRAMs that are based on second-generation MRAM technology. Results from this STT-MRAM heavy-ion testing are compared to heavy-ion test results from Honeywell toggle-bit MRAMs that are based on first-generation MRAM technology. Based on this testing, the changes in the Magnetic Tunnel Junction (MTJ) between first-generation and second-generation MRAM technology were not observed to degrade heavy-ion characteristics; and heavy-ion performance potentially may have been improved.