ANNEALING STUDIES OF VACANCIES IN PROTON IRRADIATED SILICON

Annealing of vacancies produced by heavy proton irradiation of float-z one (Fz) and P-doped Czochralski-grown (Cz) silicon has been investiga ted by positron lifetime spectroscopy. In Fz-Si divacancies are retain ed after irradiation, and these defects are completely annealed out at 700-degrees-C. In Cz P-doped silicon, impurities are found to enhance both the amount of retained vacancies as well as the tendency for vac ancy clustering. Two annealing stages appear at 100-degrees-C and clos e to 450-degrees-C which seem to be a result of interstitial migration . Vacancy migration takes place in a wide temperature range between 10 0 and 1000-degrees-C.