engleski

Formation of three dimensional quantum dot lattices in amorphous systems

Materials containing regularly ordered quantum dots (QDs) in solid matrices, called QD lattices, attract great attention due to their exceptional properties and many relevant applications. Their properties can be designed by the size and shape of the QDs, their arrangement, and by the properties of the matrix itself. The QD lattices are usually produced by the growth of crystalline multilayer films, or via synthesis from colloidal suspensions. We present two novel methods for the preparation of QD lattices in amorphous matrices. The methods are based on magnetron sputtering deposition and they allow control over QD size, shape, and arrangement in the matrix. The first method is based on the influence of the surface morphology on the nucleation positions of the QDs. The self-assembled growth, achieved using this method, is applied for the production of Ge QD lattices in amorphous SiO2 and Al2O3 matrices. The second method is based on ion-beam irradiation of multilayer films. The ion passage through the film causes local temperature increase that induces formation of regularly ordered QDs along the irradiation direction. Using this method we have prepared Ni and Ge QD lattices in amorphous SiO2 matrix. We also present Monte-Carlo models for the simulation of the both above-mentioned self-assembly processes. In addition, we demonstrate the theory and application of grazing incidence small angle x-ray scattering (GISAXS) on structural description of QD lattices.

QD lattices; GISAXS; Monte-Carlo models

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