Effects of the amorphous-crystalline transition on the luminescence of quantum confined silicon nanoclusters

Quantum confinement properties in silicon nanostructures are studied in silicon oxide and silicon nitride films at the amorphous/crystalline transition. The silicon cluster state is controlled with the annealing temperature. In both amorphous and crystalline structures, an intense luminescence is observed in the visible range at room temperature. It is shown that the luminescence intensity and the confinement energy are stronger in the crystalline state than in the amorphous state. These experimental results are consistent with previous electronic structure calculations of silicon nanoclusters.