Shielding design to mitigate neutron-induced single event upsets in space

We evaluated charged particle and neutron environments in space modules constructed from various structural materials using Monte Carlo simulations. Error rates due to single event upsets (SEU) in silicon devices were also assessed. Charged particle environments in modules constructed from organic composite materials closely resemble those in conventional aluminum structures, whereas neutron environments showed notable differences. Compared to aluminum, organic composites reduced SEU rates by up to 55 %. Under a human habitat assumption with an additional water structure, thermal neutrons below 100 meV contribute approximately 10 % of the SEU rates through the ¹⁰B(n, α) reaction. This contribution from thermal neutrons could be effectively eliminated using a 100-μm-thick thermal neutron absorption coating enriched with Gd₂O₃. These results suggest that organic composite materials, in combination with thermal neutron absorption paint, offer potential advantages for radiation safety in space by protecting both humans and electronic devices.