All-silicon solid films with highly efficient and tunable full-color photoluminescence

Silicon nanocrystals with the most probable diameter of 2 nm are surface passivated by glycerol and deposited on porous silicon (PS) substrate with intrinsic red photoluminescence. Tunable full-color emission is observed from this composite film and the quantum efficiency varies from 17% to 28% under different excitation wavelengths. Spectral analysis reveals that the full-color emission arises from combined quantum confinement in the silicon and PS nanocrystals with glycerol passivation. The nanostructured all-silicon film is robust and compatible with microelectronic processing.