Apparatus for removing minute particles from a substrate

Abstract From the Canadian patent

Apparatus for removing small particles from a substrate comprising a source of fluid carbon dioxide a, first means for expanding a portion of the fluid carbon dioxide into a first mixture containing gaseous carbon dioxide and fine droplets of liquid carbon dioxide coalescing means for converting the first mixture into a second mixture containing gaseous carbon dioxide and larger liquid droplets of carbon dioxide second expansion, means for converting said second mixture into a third mixture containing solid particles of carbon dioxide and gaseous carbon dioxide, and means for directing said third mixture toward the substrate. Also disclosed are methods for removing fine particles from …