The suppression of dislocation formation and of transient B diffusion, by C co-implantation, was studied by means of transmission electron microscopy, secondary ion mass spectrometry, photoluminescence spectroscopy and high-resolution X-ray diffraction techniques. It was shown that both effects were due to the formation of C-related damage which acted as traps for Si interstitials. Quantitative simulations indicated that this damage was probably caused by the co-precipitation of Si and C atoms as Si1.15C complexes. The latter also degraded the electrical properties of the implanted layers. They dissolved at annealing temperatures that were higher than 900C. When this occurred, the effect of the C was reduced. Dislocations, transient B diffusion and recovery of the electrical properties were then observed.

Dislocation Formation and B Transient Diffusion in C Coimplanted Si. A.Cacciato, J.G.E.Klappe, N.E.B.Cowern, W.Vandervost, L.P.Biró, J.S.Custer, F.W.Saris: Journal of Applied Physics, 1996, 79[5], 2314-25