Pulse laser-induced size-controllable and symmetrical ordering of single-crystal Si islands

Optically electric- and magnetic resonance-induced dielectric nanostructures have garnered significant attention due to applications as tunable electronic and optoelectronic device. In this letter, we describe an ultrafast and large-area method to construct symmetrical and single-crystal Si island structures directly on Si substrates by a pulse laser dewetting method. The tunable surface electric field intensity distribution could convert the stochastic dewetting process into a deterministic process (classical dipole mode and Mie resonance dipole mode) on predefined Si pit arrays via laser dewetting. Under this condition, these pre-patterned Si substrate structures not only induced high spatial ordering of islands, but also improved their size uniformity. By adjusting the laser fluence, the diameter of the single-crystal Si islands could be selected in the range 41.7-147.1 nm.