An Area-Efficient 65 nm Radiation-Hard Dual-Modular Flip-Flop to Avoid Multiple Cell Upsets

A layout structure to avoid upsets due to Multiple Cell Upsets (MCUs) is proposed for rad-hard dual-modular Flip-Flops (FFs) called BCDMR (Bistable Cross-coupled Dual-Modular Redundancy) by separating critical components. We have fabricated a 65 nm chip including 30 kbit dual-modular FF arrays on twin-well and triple-well structures. High-energy broad-spectrum neutron irradiations reveal that no soft error is observed up to 100 MHz in the twin-well, but some errors are observed in the triple well. The triple-well structure is sensitive to MCUs because the p-well potential can be easily elevated.