Radiation Hardened Flip-Flops with low Area, Delay and Power Overheads in a 65 nm bulk process

Abstract

We propose two types of radiation-hard flip-flops named PLTGFF and FBTIFF with low ADP (area, delay and power) overheads by increasing critical charge ( <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$Q_{\text{crit}}$</tex> ) at weak nodes. They have additional transistors and wires. PLTGFF has the area, delay, and power overheads by 5%, 4%, and 10%, respectively. FBTIFF has the area, delay, and power overheads by 42%, 10%, and 22%, respectively. They were fabricated in a 65 nm bulk process. a-particle irradiation tests revealed that <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha$</tex> - SERs of PLTGFF and FBTIFF were suppressed by 45% and by 90% than that of STDFF. By spallation neutron irradiation tests, neutron-SERs of PLTGFF and FBTIFF were suppressed by 18% and by 35% than that of STDFF. In the terrestrial environment, the proposed FFs have better trade-offs between reliability and performance than these of multiplexed FFs with large overheads.