Computational study of hybrid DDQ/LiI/WO₃ composites for multi-radiation shielding in microelectronic applications

Effective radiation shielding is essential for ensuring the long-term reliability and operational safety of sensitive electronic systems operating in radiation-harsh environments, including radiotherapy facilities, nuclear reactors, and space missions. In this study, novel DDQ/LiI/WO₃ hybrid composites containing 0-35 wt% WO₃ were proposed and systematically evaluated as lightweight multi-radiation shielding materials against photons, charged particles, and neutrons. Photon attenuation was investigated using MCNP and PHY-X, while SRIM and ESTAR were used to assess charged-particle interactions, and the fast-neutron removal cross section was evaluated for neutron attenuation. Increasing WO₃ loading significantly enhanced photon attenuation; at 0.1 MeV, the optimized MC-W35 composite achieved a mass attenuation coefficient of 1.778 cm²/g and a low half-value layer of 0.135 cm. From a mass-efficiency perspective, MC-W35 exhibited a notably low areal density of 0.39 g/cm² per HVL, corresponding to more than 90% lower shielding mass than conventional epoxy and polyimide matrices and approximately a ten-fold reduction relative to ordinary concrete. Secondary-radiation analysis further showed that photon-induced radiation yield decreases rapidly above 1 MeV, while electron-induced Bremsstrahlung remains suppressed, reaching less than 0.16 at 10 MeV, owing to the low average atomic number of the DDQ matrix. The enhanced fast-neutron attenuation and reduced charged-particle ranges further demonstrate the multi-radiation shielding capability of the composite. Overall, these findings identify DDQ/LiI/WO₃ hybrid composites, particularly MC-W35, as promising lightweight candidates for radiation protection of electronic systems and components operating in diverse medical, industrial, nuclear, and space radiation environments.