an apparatus for producing high - purity standard particles produces nanometer - sized high - purity standard particles of monodispersive uniform structure efficiently , with the abatement of contamination and damage . the apparatus includes a particle generation chamber , a particle classification chamber and a particle collecting chamber . the particle generation chamber excites a semiconductor target with pulse laser beam under a low - pressure rare gas ambient so as to detach and eject materials from the target into the ambient gas , in which those materials are condensed and grow into high - purity particles . the particle classification chamber subjects the high - purity particles as generated to classification , and the particles collecting chamber collects high - purity standard particles as classified onto a substrate .