Characterization of Heavy-Ion-Induced Single-Event Effects in 65 nm Bulk CMOS ASIC Test Chips

Two 65 nm bulk complementary metal-oxide-semiconductor (CMOS) digital application-specific integrated circuit (ASIC) chips were designed, and then tested in a heavy ion accelerator to characterize single-event effects (SEE). Test chip 1 incorporates test structures, and test chip 2 implements an unhardened and a hardened digital signal processing (DSP) core. Our testing results reveal the radiation effects on the low-voltage and high-frequency operations of the ASIC chips. At a low supply voltage of 0.7 V, cross sections increase by a factor of 2 to 5 at low linear energy transfer (LET), while the increase in cross section at high LET is almost negligible, suggesting that the charge conveyed by heavy ion has far exceeded the critical charge and tuning the supply voltage is not effective. Increasing the clock frequency increases the relative importance of single-event transients (SET) compared to single-event upsets (SEU), especially in hardened designs due to their better SEU immunity. The hardened DSP core experiences a factor of 2 increase in cross section when its clock frequency is increased from 100 MHz to 500 MHz.