Rapid thermal annealing (1050C, 1119C) was used to perform short-term Au diffusion experiments on dislocation-free float-zone material with a {100} orientation. The concentration versus depth profiles were measured by using the spreading resistance technique, and were found to be well described in terms of the kick-out mechanism, which involved the generation of Si self-interstitials. In particular, the Au incorporation rate appeared to be controlled by the out-diffusion of excess self-interstitials towards the surfaces. The measurements revealed a continuous increase, in the Au boundary concentration, which approached the relevant solubility limit only after prolonged annealing. This was interpreted in terms of a limited effectiveness of Au-alloyed {100} Si surfaces as sinks for self-interstitials. This interpretation was supported by computer modelling of the experimental data, which yielded finite values for the self-interstitial surface-annihilation velocity.

Diffusion of Gold in Silicon during Rapid Thermal Annealing - Effectiveness of the Surface as a Sink for Self-Interstitials. W.Lerch, N.A.Stolwijk: Journal of Applied Physics, 1998, 83[3], 1312-20