Wafers which had been oxidized and stripped, by using reactive plasma etching, were implanted with 5keV B to a dose of 1013/cm2. Transient enhanced diffusion of B, which was usually observed in implanted samples, was strongly retarded in the plasma-etched samples upon annealing at 800, 900 or 1000C; as measured by using secondary ion mass spectrometry. The results suggested that the defects, which were generated in the near-surface region by the plasma-etching procedure, represented an efficient sink against the flow of interstitials which caused transient enhanced diffusion. Slow release of interstitials from this immobile trapping background occurred over characteristic time-scales. However, these were 30 to 60 times longer than the usual lifetimes of transient diffusion. This release was characterized by an activation energy of 2.4eV.

The Effect of Reactive Plasma Etching on the Transient Enhanced Diffusion of Boron in Silicon. V.Privitera, F.Priolo, G.Mannino, S.U.Campisano, A.Carnera, G.Arena, C.Spinella: Applied Physics Letters, 1997, 71[13], 1834-6