PURPOSE: To provide a superprecise cleaning capable of removing dirty metals by using an acid-containing water soln. for a washing liq. to be evaporated in cleaning of the surface of works with resultant vapor.
CONSTITUTION: Chemical liqs. S1 and S2 in storage tanks 3a and 3b are heated by heaters 5 to produce the vapors of the liqs and wafers 2 are washed with the vapors. The vapors are mixed when rising in a casing 1 to produce the vapor of a washing liq. having specified compsn. and it arrives at the wafers 2 and dews on their surfaces. The tanks 3a and 3b have chemical liq. feed pipes 6a and 6b and chemical liq. drain pipes 7a and 7b, respectively. The washing liq. uses an acid-containing water soln. The acid is pref., at lest, one selected from among hydrofluoric, hydrochloric, phosphoric, nitric, acetic, trichloroacetic, dichloroacetic and monochloroacetic acids, and if two of them are selected, they are pref. stored in two tanks 3a and 3b.
OTSUKA SUSUMU
KAMIMURA KENICHI
MORI YOSHIHIRO
