Structures and optical properties of silicon nanocrystallites prepared by pulsed-laser ablation in inert background gas

Silicon (Si) nanocrystallites have been synthesized using pulsed-laser abla tion in inert background gases, for studying the structures and optical pro perties as one of the quantum confinement effects. We extracted a process c ondition where well-dispersed Si nanocrystallites devoid of droplets and de bris are prepared, by varying excitation laser conditions. Furthermore, we investigate the influence of the inert background gas pressures on transiti on from amorphous-like thin films to nanocrystallites. It was clarified tha t there is a processing window of the inert background gas pressure in whic h the quantum confinement effects for carriers and phonons become apparent. (C) 2000 American Institute of Physics. [S0003-6951(00)00611-2].