AMS STUDIES OF THE DIFFUSION OF CHLORINE IN SILICON-WAFERS

The diffusion of chlorine implanted in silicon wafers has been studied by neutron activation/accelerator mass spectrometry. Two implantation energies, 200 and 400 keV, and a range of implant doses from 10(13) to 10(15) atoms/cm(2) were employed. The diffusion temperatures and times were also varied. While there is a distinct difference between the annealed and the as-implanted depth profiles for the lowest implant doses studied, at higher doses the chlorine seems to be virtually immobile. There is minimal indiffusion for the experimental conditions studied. However outdiffusion is substantial and rapid for anneal temperatures of 1100 degrees C and above. This behavior is similar to that reported for fluorine in silicon at lower temperatures and quire different from that observed for dopants and other impurities.