STUDY OF ALPHA-RADIATION-INDUCED DEEP LEVELS IN P-TYPE SILICON

Deep levels introduced by 5.48 MeV alpha particles in p-type silicon h ave been studied using deep-level transient spectroscopy, The generati on rates of these defects have been obtained up to a dose of 1.2 X 10( 11) alpha particles/cm2. Detailed data have been obtained on the elect rical characteristics of the two deep levels in the lower-half band ga p at E(v) + 0.21 eV and E(v) + 0.35 eV and one level in the upper-half gap of silicon at E(c) - 0.25 eV introduced by irradiation. These cha racteristics include emission rate signatures, carrier capture cross s ections, and their temperature dependence and deep-level concentration s. Detailed isochronal annealing measurements have been performed to o btain data on the annealing behavior of the deep-level defects and als o to help identify these centers. Some interesting phenomena relating to temporal changes in our deep level spectra stimulated by minority c arrier injection have been observed and discussed in the light of the available literature on radiation-induced defects in silicon.