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

Deep levels introduced by 5.48 MeV alpha particles in p-type silicon have been studied using deep-level transient spectroscopy, The generation 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 electrical characteristics of the two deep levels in the lower-half band gap 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 characteristics include emission rate signatures, carrier capture cross sections, and their temperature dependence and deep-level concentrations. Detailed isochronal annealing measurements have been performed to obtain data on the annealing behavior of the deep-level defects and also to help identify these centers. Some interesting phenomena relating to temporal changes in our deep level spectra stimulated by minority carrier injection have been observed and discussed in the light of the available literature on radiation-induced defects in silicon.