Sherbet-like cleaning composition and method and system for cleaning substrate

A system for cleaning a substrate according to the present invention comprises an apparatus for producing a sherbet-like composition consisting of snow ice grains and a chemical agent, holder means for holding a substrate to be cleaned, supply means for supplying to the substrate the sherbet-like composition for cleaning the substrate, and means for moving the sherbet-like composition being supplied relative to at least one of the surfaces of the substrate. The sherbet producing apparatus comprises a mixing vessel for mixing the chemical agent and pure water in a predetermined temperature mixing ratio to form a mixture, means for supercooling the mixture uniformly therethroughout at a predetermined lower than the freezing point of the pure water and greater than that of the chemical agent, an impeller blade having a generally vertically extending axis of rotation for stirring the mixture uniformly within the mixing vessel to produce the sherbet-like composition, the impeller blade having side edges which are each located so that there is a gap between each edge and the inner wall of the mixing vessel sufficient to prevent the edges from coming into contact with the inner wall of the mixing vessel during the rotation of the impeller blade, whereby the sherbet-like composition is used to remove particles from said at least one of the surfaces of the substrate.