The size distribution of Si nanoparticles prepared by pulsed-laser ablation in pure He, Ar or Ne gas

Nanocrystalline silicon films were prepared by pulsed-laser ablation in high-purity He, Ar or Ne gas at room temperature under a deposition pressure of 10Pa. The Raman and Xray diffraction spectra indicate that the films are nanocrystalline. Scanning electron microscopy images show that Ar or Ne gas, compared to He gas, yields smaller and more uniform-sized Si nanoparticles at the same deposition conditions, which is also confirmed by the blue-shifted and narrower peaks obtained in photoluminescence measurement. Ne gas induces the smallest and most uniform, in size, Si nanoparticles among all the three gases, which may be attributed to a more effective energy transfer between Si and Ne atoms resulting from the adjacent degree of the atomic weights.