Positron trapping rates and their temperature dependencies in electron-irradiated silicon

Defects created by 2-MeV electron irradiation of Czochralski-grown silicon have been investigated with use of positron-lifetime spectroscopy and results have been correlated with EPR and ir data. The trapping rate for the positrons was smallest for the neutral divacancy where a concentration of ∼1017 cm-3 gave rise to a trapping rate of 1 ns-1. For the singly negative divacancy the trapping rate was increased at 300 K by a factor of about 3.5 …