Displacement damage of the space broad-spectrum proton in semiconductor materials

Abstract Displacement damage induced by high-energy protons in the space radiation environment presents a serious risk to the reliability of spacecraft materials and onboard electronics. Nevertheless, studies on displacement damage induced by space-based broad-spectrum protons are still limited. In this paper, the nonionizing energy loss (NIEL) of space broad-spectrum protons at different orbital altitudes in semiconductor materials is investigated using Geant4 Monte Carlo simulations. We find that the NIEL of silicon (Si) and gallium arsenide (GaAs) first increases and then decreases with orbital altitude, and that shielding effects can result in either the saturation or continuous increase of NIEL, depending on the shielding layer thickness. A fast NIEL calculation method for arbitrary broad spectra is proposed based on statistical probability principles and the effective proton proportion. Meanwhile, a more uniform spatial distribution of mean damage energy per source particle ( T dam ) deposition from broad-spectrum protons can be achieved by increasing the shielding layer thickness and lowering the orbital altitude. Notably, the relative contribution of displacement damage caused by nuclear reactions decreases with increasing orbital altitude and shielding layer thickness. The results provide a quantitative reference for space displacement damage in semiconductor materials.