A simple model of radiation swelling of silicon

The radiation swelling of silicon is explained as a diffusion-like process where the flux of interstitials out of the plane is defined by the gradient of the concentration of interstitials and the gradient of mechanical stresses in the ion-implanted region of the solid. This model was applied to describe the dynamics and the main regularities (dependence of strain on the ion flux density, ion energy, substrate temperature) of ion implanted silicon (Ni⁺, E = 40–160 keV, j = 5–180 μA cm⁻²). It is demonstrated that suppression of radiation swelling at high temperatures of the substrate or high ion beam current density can be explained by the annihilation of radiation defects.