Abstract: A method and an apparatus of disposing dust produced during a process for forming an amorphous silicon film, which method and apparatus, for the purpose of safely and quickly collecting the dust and of making it possible to form the collected dust to a solidified mass or pellet form to facilitate subsequent handling thereof, comprises: dust-capturing means for collecting the dust adhering to either the entire or partial portions of the film-forming unit without causing scattering of the dust to the outside of the apparatus; a dust hopper capable of receiving, through a pipeline, the dust collected by the dust-capturing means; a bucket filled with a trifluorotrichloro-ethane liquid to render to a slurry-form the dust supplied thereinto an appropriate rate from the dust hopper; and a heat-distilling means to distill the trifloro-trichloro-ethane liquid by heating the bucket to retain therein solidified mass or pellets of dust.