Beam-based positron annihilation spectroscopy was applied to the study of near-surface vacancies created by 2keV B+ ions implanted into Cz Si. The use of a controllable-energy positron beam means that the probe could be tuned to maximize the response to the subsurface damage. Time-dependent changes were observed in the near-surface vacancy concentration profile. For example, after one week at room temperature, exposure of an implanted sample to white light for 1h resulted in the migration of about 95% of the measurable damage to sinks—primarily, it was assumed, to the surface. The relative importance of temperature, air, and light was investigated.

Room-Temperature Evolution of Vacancy-Type Damage Created by 2keV B+ Implantation of Si. R.M.Gwilliam, A.P.Knights, C.P.Burrows, P.G.Coleman: Journal of Vacuum Science and Technology B, 2002, 20[1], 427-30