Ions of He+ were implanted at 800C into (100) Si, using multiple energies and various fluences, so as to get the number of displacements per atom constant over a large plateau. The ion-related defects were studied mainly by transmission electron microscopy. Both the number and the microstructure of defects were found to be strongly dependent upon the order of implants. Faceted cavities were only observed where damage overlapping occurred. The first implant provided thus nucleation sites for cavities. The generation of these sites was less efficient when using increasing energies because of damage recovery; fewer cavities were observed. Concurrently interstitial-type defects, {113} agglomerates, were formed. The observed state of growth of these {113} defects (rod-like and ribbon-like defects) depended upon the implantation energy order but, in any case, no dislocation loops were observed; even in the deepest damage region.

Radiation Damage in He Implanted Silicon at High Temperature using Multi-Energies. M.L.David, A.Ratchenkova, E.Oliviero, M.F.Denanot, M.F.Beaufort, A.Declémy, C.Blanchard, N.N.Gerasimenko, J.F.Barbot: Nuclear Instruments and Methods in Physics Research B, 2002, 198[1-2], 83-9