Spherical-Square-Well Defect-Potential Model for 1-MeV Electron Irradiated Defects in Silicon

A spherical-square-well model for defect potentials is fitted to fourteen defects observed in electron-irradiated silicon. The thermal activation energy is taken as the ground bound state in the well and the radius of the well a is obtained from the experimental thermal emission cross section, σ=πa². An empirical relationship was observed between the well depth V₀ and the radius, V₀=(9±1)a^1.3±0.1. Other authors have used a spherical-square-well model to calculate the photoionization cross section and the electric field dependence of the thermal-emission rate. These calculations are compared to measurement results with rough agreement.