Design of 65 nm CMOS SRAM for Space Applications: A Comparative Study

We study the design of different 6T and DICE SRAM blocks based on a commercial 65 nm CMOS technology and discuss the experimental results for X-ray, proton and heavy ion irradiation campaigns. The results obtained show that the number of affected bits depends not only on LET value, but also on the location of a strike. MCU patterns are discussed. The sensitive area is estimated as the whole SRAM cell area after deduction of the region between N+ and P+ guard rings. The results for normally incident particles clearly showed the advantages and trade-offs of different circuit and layout techniques.