In several fields such as space engineering, it is very important to evaluate the performance degradation of electronic components by high-energy protons.
Charged particles such as protons cause excitation or ionization in semiconductor crystals. However, a very small fraction of the energy loss is then used to displace atoms from their equilibrium positions to create primary displacement atoms (non-ionizing processes). The generated primary displacement atoms cause cascade processes by displacing many atoms, which proceed until the transferred energy becomes smaller than the threshold required to displace the atoms. In the space environment, the defects created by incident particles create new energy levels within the band gap, and the levels change the electrical and optical properties of the electronic device and material. In other words, the protons in space environment cause single-event effects (SEE), total ionization dose (TID) effects, and displacement damage dose (DDD) effects in the electronic device.
In terms of the proton-induced DDD effect, the most sensitive electronic component is bipolar devices. Generally, proton accelerators, 1 MeV neutron source, and 1 MeV electron source are used to estimate the DDD effect in bipolar devices.
Considering the high cost for testing these methods, Kang Myong Chol, a section head at the Faculty of Electronics, proposed a method of evaluating the proton-induced DDD effect on the bipolar devices by using the existing Pu-Be isotope neutron source. Then, he verified the accuracy of the proton-induced DDD effect estimation using the Pu-Be isotope neutron source by using the optocouplers, TLP521-1GB and PC817C.
The proposed method can be used to evaluate the durability of electronic devices operating in proton environments.
You can find more information in his paper “Proton Induced Damage Estimation in Bipolar Device” in “Proceedings of KUTIC-2025”.