Transient Enhanced Diffusion of Boron

Integrated circuit technology requires a reduction in device dimensions. The junction depth, where the donor and acceptor concentrations are equal, is set between 10 and 30 nm. These shallow junction requirements restrict ion implantation technology - not on the implantation procedures themselves, but on the subsequent diffusion of the implanted species during thermal annealing. 

Nearby vacancies and interstitials recombine either dynamically during irradiation or subsequently during postimplant annealing. Extra atoms corresponding to the implant dose at end-of-range defect positions are responsible for TED. However, since the momentum transfer from an incident ion to a target atom is in the forward 

The implantation of MeV Si ions into a Si substrate can also suppress boron-enhanced diffusion normally associated with a high boron concentration layer (Shao et al. 2003). Junction depths of 20 nm were achieved in samples implanted with 0.5 keV B ion at a dose of 1015 cm-2 following a 1,000°C thermal anneal. 

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Jain, S.C., Schenmaker, W., Lindsay, R., Stak, P.A., Decoutere, S., Willander, M., Maes, H.E. Transient enhanced diffusion of boron in Si, Applied Physics Reviews. J. Appl. Phys. 91, 8919-8949 (2002)... 

H.E. Transient enhanced diffusion of boron in Si, Applied Physics Reviews. J. Appl. Phys. 91, 8919-8949 (2002)... 

Gunawan, R., Jung, M.Y.L., Seebauer, E.G. and Braatz, R.D. (2003b) Parameter Sensitivity Analysis of Boron Activation and Transient Enhanced Diffusion in Silicon. J. Electrochem. Soc., 150, G758-G765. 

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