An Energy-Efficient Low-Area Double-Node-Upset-Hardened Latch Design

The energy-efficient circuits, though important in IoT and biomedical applications, are vulnerable to soft errors due to their low voltages and small node capacitances. This paper presents an energy-efficient low-area double-node-upset-hardened latch (EEDHL). The proposed latch enhances the radiation hardness by employing a restorer circuit based on a Muller C-element and a memory element. The post-layout simulations show that the EEDHL improves the area–energy–delay product (AEDP) by [Formula: see text]80% compared to the newly reported double-node-upset-resilient latch (DNURL) in STMicroelectronics 65-nm CMOS technology. Synopsys TCAD mixed-mode simulations in 32-nm CMOS technology framework are also used to validate the proposed DNU-hardened latch. The proposed EEDHL effectively mitigates the DNU at the strike with a linear energy transfer (LET) equal to 160[Formula: see text][Formula: see text]/mg in 32-nm CMOS technology.

Proton-Cluster-Beam Lethality and Mutagenicity in Bacillus subtilis Spores

The unique energy transfer characteristics of swift cluster ions have attracted the attention of many researchers working on the analysis or processing of material surfaces, but the effects on living organisms remain unclear. We irradiated B. subtilis spores with monomer and cluster proton beams and examined their lethality; the 2 MeV H2+ shows a clearly lower lethality than 340 keV H+, even though both have a comparable linear energy transfer. The 2 MeV H2+ dissociates into a pair of 1 MeV H+ by losing the bonding electrons at the target surface. The estimated internuclear distance and the radial dose distribution suggest that the spread of deposited total energy over two areas separated by just several nanometers greatly diminishes beam lethality and that the energy density in the very center of the trajectory, possibly within a 1 nm radius, has a great impact on lethality. We also performed a whole genome resequencing of the surviving colonies to compare the molecular nature of mutations but failed to find a clear difference in overall characteristics. Our results suggest that cluster beams may be a useful tool for understanding biological effects of high linear energy transfer radiation.