When a semiconductor film is irradiated by γ-rays, orbital electrons including valence electrons are excited to the conduction band by Compton scattering, and holes are introduced as a result. Because these electrons and holes have strong reducing and oxidizing activities, respectively (we call this phenomenon as ‘RISA’), the cathodic and anodic reactions between the material and the solution will progress as shown in the figure, resulting in a drop in corrosion potential.

The proposed RISA corrosion protection method is non-sacrificial. It utilizes radiation energy without adding chemicals to a solution.