Preparation and evaluation of nitrogen-terminated silicon nanoparticles: laser annealing effect

Nitrogen-terminated silicon nanoparticles were synthesized on AFI AlPO4-5 zeolite by pulsed laser ablation of silicon target in the presence of 1.33×10−5 Pa of ammonia and were annealed by multiple laser shots at 532 nm. The samples were characterized by X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy and UV–vis absorption measurements. The results indicate that they are composed of nonstoichiometric silicon nitride nanoparticles as well as silicon species with dangling bonds. NHx (x=1,2) polyhydride species are dissociated by pulsed laser annealing, which shows the improvement of the silicon and silicon nitride crystallinities. It is suggested that the nanoparticles will agglomerate as clusters after laser annealing. According to the Tauc plot obtained from UV–vis absorption data, a blue shift of band gap energy from bulk silicon was observed.