A systematic and quantitative study was made of the extended defects formed after high-dose proton implantation in Si. This study was based on the transmission electron microscopy and secondary ion mass spectroscopy experiments to monitor the thermal evolution of platelets and voids for a large variety of annealing conditions up to 900C. Up to about 500C, only platelets were observed and, as annealing proceeds, they grow in size and reduce their density through the conservative exchange of H atoms. On the contrary, above 500C, H starts to diffuse out of the defect-rich region and this out-diffusion could be completed after 700C annealing. Concurrently, platelets tend to disappear and voids appear. Upon annealing at above 700C, H could no longer be detected in the layers and only voids remained. With time, they also grew in size and reduced in density. This was again attributed to the Ostwald ripening of voids which now involved vacancy diffusion from small voids to large ones. In summary, it was shown that platelets and voids both underwent quasi-conservative ripening during annealing; at low-temperatures, platelets exchanged the H atoms which they were composed of while, at high temperatures, voids exchanged vacancies.

Kinetic Aspects of the Growth of Platelets and Voids in H Implanted Si. J.Grisolia, F.Cristiano, G.Ben Assayag, A.Claverie: Nuclear Instruments and Methods in Physics Research B, 2001, 178[1-4], 160-4