Negative and Positive Muon-induced SEU Cross Sections in 28-nm and 65-nm Planar Bulk CMOS SRAMs

In this paper, we compare the negative and positive muon-induced SEU event cross sections of 28-nm and 65-nm planar bulk CMOS SRAMs. Our measurement results show a 3.6 X increase in muon-induced SEU event cross section from 65-nm to 28-nm technology, and negative muon-induced SEU event cross section is 3.3 X larger compared to positive muons at 28-nm technology. This result is consistent with the previous works reporting muon-induced SEU event cross section increases with technology scaling. The measured result also suggests the contribution of direct ionization to the total SEU event cross section is 54.1 % at 28-nm node with operating voltage of 0.6 V while it is 1.8 % at 65-nm node with 0.9 V.