A study was made of the redistribution of As and B during rapid thermal annealing from implantation-doped polycrystalline Si films into underlying monocrystalline Si. Arsenic (2 x 1015 or 5 x 1015/cm2, 100keV) and B (1016/cm2, 25keV) co-diffusion were studied in the emitter and extrinsic base of bipolar transistors in p-n-p configuration. The object was to test the effect of As fluence upon B redistribution during annealing (1000 to 1150C, 1 to 20s). The increased As fluence produced a delay in B diffusion, which became more significant at 1150C. At this temperature, stopping was expected at 500Å.

The Effect of Arsenic Fluence on the Boron Diffusion in the Polysilicon on Monosilicon During Rapid Thermal Annealing. A.Merabet, J.Marcon: Nuclear Instruments and Methods in Physics Research B, 2006, 253[1-2], 122-5