GISAXS study of shape and size of CDS nanocrystals formed in monocrystalline silicon by ion implantation

Grazing incidence small angle X-ray scattering (GISAXS) was applied to study size and shape as well as distribution of US nanocrystals formed in monocrystalline silicon substrate by separate implantation of constituent elements with a dose of 4.5 x 10(16)/cm(2) each, and subsequent annealing at 1000 degreesC. Apart from surface scattering, the 2D GISAXS patterns also show a particle contribution, which is twofold: diffuse scattering centered at the direct beam position, and two streaks at both sides, crossed at the direct beam position, coming from the surface scattering from the facets of the particles. The streak inclination to the sample surface corresponds to the silicon (1 1 1)-plane angle, where there is a minimum in nanocrystal growth energy. From the intensity distribution along the streak, the sizes of the facets are determined and compared to the overall particle sizes determined from the diffuse part of the scattering in order to gain information about the nanocrystal shape. (C) 2002 Elsevier Science B.V. All rights reserved.