Comparison of Total Ionizing Dose Effects in 22-nm and 28-nm FD SOI Technologies

Abstract

Total ionizing dose (TID) effects from Co-60 gamma ray and heavy ion irradiation were studied at the 22-nm FD SOI technology node and compared with the testing results from the 28-nm FD SOI technology. Ring oscillators (RO) designed with inverters, NAND2, and NOR2 gates were used to observe the output frequency drift and current draw. Experimental results show a noticeable increased device current draw and decreases in RO frequencies where NOR2 ROs have the most degradation. As well, the functionality of a 256 kb SRAM block and shift-register chains were evaluated during C0-60 irradiation. SRAM functionality deteriorated at 325 krad(Si) of the total dosage, while the FF chains remained functional up to 1 Mrad(Si). Overall, the 22-nm FD SOI results show better resilience to TID effects compared to the 28-nm FD SOI technology node.