Growth of a Si nanocrystal in an oxygen atmosphere. Computer simulation

Growth of a Si nanocrystal in vacuum and in atomic-oxygen atmosphere was simulated on the basis of molecular dynamics. SiOx nanoparticles (x = 0–0.42) containing up to 302 atoms were obtained. The shape of the nanocrystals was primarily determined by the amount of oxygen contained in them. The growth of nanocrystals in an oxygen atmosphere was accompanied by the formation of oxygen clusters inside a nanoparticle, which gave rise to considerable internal stresses. In most cases, structural relaxation increases the volume of SiOx nanocrystals and decreases internal pressure. The angular and topological statistical characteristics of Voronoi polyhedra are indicative of a structural irregularity in oxygen clusters formed inside Si nanoparticles.