Using B and Sb doped Si(100) doping superlattices (DSL) as tracers of
native Si point defect behavior it is shown that vacuum annealing at 8
10 degrees C leads to a depletion of Si self-interstitials, with their
smallest concentration at the surface, but does not affect the vacanc
y population. At a fixed depth, the interstitial concentration drops f
or increasing annealing times; for a given time, the interstitial conc
entration increases into the sample as a function of depth. Inert anne
als of a B-DSL in Ar show flat interstitial profiles. Apparently, the
vacuum anneal makes the surface a better sink for interstitials than a
n inert Ar anneal, leading to an equilibrium interstitial concentratio
n below the value in the bulk and establishing a net outflow of inters
titials to the surface. The absence of a response of the vacancy popul
ation yields a lower limit on the interstitial-vacancy recombination t
ime of 10(4) s at 810 degrees C. Process simulation of this scenario c
aptures the essential trends of the experimental data. (C) 1995 Americ
an Institute of Physics.