The effect of fluorine on electron trapping in SiO2films has been studied by avalanche electron injection. Samples are prepared by 25‐keV fluorine implantation into dry oxides followed by a 1000 °C N2ambient anneal. Bulk electron traps with capture cross sections on the order of 10−17–10−19cm2, which are not due to implantation damage, are filled by avalanche electron injection. An optimum dosage of fluorine implantation to suppress the so‐called turnaround effect during avalanche injection exists. This suggests that fluorine might passivate slow interface donor states or reduce bulk hydrogen diffusion. The observation that high‐temperature (120 °C) injection can eliminate most fast and slow interface states for conventional oxides is also true for fluorinated oxides. Our results indicate an enhanced generation of fast donor states for oxides containing fluorine. These states contribute a positive charge when the Fermi level is in the lower portion of the band gap.