Si nanoclusters generated in Si-SiO2 structures implanted with different doses of Si ions

Abstract

Topography changes of a SiO2 surface and formation of Si nanoclusters, induced by high-energy electron irradiation of ion implanted Si-SiO2 structures, are studied by atomic force microscopy (AFM) measurements. Si ions with energy of 15 KeV and doses of 1012 or 1016 cm−2 are implanted in the Si-SiO2 structures with an oxide thickness of 20 nm. The ion energy is chosen to produce maximum ion damage at the Si-SiO2 interface. Some of the implanted samples are simultaneously irradiated by 20 MeV electrons with a flux of about 1×1015 cm−2. AFM measurements indicated that the SiO2 topography does not vary significantly only due to the ion-implantation. Si nanoclusters are observed in a SiO2 layer after MeV electron irradiation. The measurements show that the size and shape of the Si nanoclusters depend significantly on the dose of the previously implanted ions.