Enhanced depth resolution in positron analysis of ion irradiated SiO2 films

We report the observation of defects following 1.7 MeV Si+ through-implantation of SiO2 films thermally grown on Si(100) substrates. Films were irradiated to fluences of 1012, 1013, and 1014 ions/cm2, and analyzed using a variable energy positron beam. Enhanced depth resolution was achieved via iterative chemical etching and measurement, for the sample irradiated to 1012 Si+/cm2, and for an unirradiated control sample. The positron annihilation …