An irradiation effect in thermally grown SiO₂

Abstract

Thermally grown silicon dioxide layers were irradiated with kilovolt electrons, and the equilibrium surface potential was measured by passing the secondary electrons through an energy analyser. The incident electrons at 5-keV energy penetrate for 3300 Å into a 5700-Å oxide film. The observed equilibrium surface potential is initially less than 1 V which indicates efficient induced conductivity; but after 10 C/cm2 it is -30 V (which indicates that the conductivity has diminished); and finally at 20 C/cm 2 it is less than 1 V again. Annealing reverses the process. A model is proposed. © 1969 The American Institute of Physics.