The depth distribution of open-volume point defects created by room temperature implantation of Czochralski Si by 100keV B+ ions at a dose of 5 x 1014/cm2 was determined by enhanced-resolution beam-based positron annihilation spectroscopy. By incremental controlled etching (via anodic oxidation of 50–100nm layers) the depth resolution of the positron annihilation spectroscopy was maintained at ~50nm by using positrons implanted at energies below 2keV to probe each layer as it brought close to the surface by the etching process. The etch depths were verified by using secondary-ion mass spectrometry to profile the B depth distribution. The results were in good agreement with Monte Carlo simulations, particularly in the traditionally difficult-to-measure deep tail region.

Direct High-Resolution Determination of Vacancy-Type Defect Profiles in Ion-Implanted Silicon. P.G.Coleman, R.E.Mason, M.Van Dyken, A.P.Knights: Journal of Physics - Condensed Matter, 2005, 17[22], S2323-30