STRUCTURAL AND ELASTIC PROPERTIES OF POROUS SILICON

We have implemented a modified diffusion-limited aggregation model to simulate the porous silicon structure obtained by electrochemical diss olution. The resulting fractal structures were fully equilibrated usin g the molecular dynamics method. An analysis of the relaxed structure shows it to be quite stable with the presence of one-, two- and three- coordinated atoms as well as the four-coordinated atoms found in bulk silicon. It is suggested that the different substructures or nanocryst als might be responsible for the observed photoluminescence.