Patent ID: 6415803
Filing Date: 2002-07-09
Classification: B08B,C11D,H01L,Y10S

Abstract:
An apparatus for cleaning semiconductor wafers and reusing a chemical cleaning solution, the apparatus comprising:(a) a chamber sized for receiving a plurality of wafers to be cleaned; (b) an outlet in the base of the chamber for draining liquids from the chamber; (c) a plenum located below the chamber, the plenum in fluid communication with the chamber via the chamber outlet, the plenum comprising at least two outlets in a base thereof; (d) at least two holding tanks, each of the tanks in fluid communication with one of the at least two outlets of the plenum to receive liquids drained through the respective outlet when the apparatus is in use; (e) a recycle system for at least one of the holding tanks, the recycle system comprising: (i) an analyzer for chemical analysis of liquid recycled in the at least one holding tank when the apparatus is in use; (ii) a particle detector for detection of particles in liquids recycled in the at least one holding tank when the apparatus is in use; and (iii) a pump with an inlet port in fluid communication with the at least one of the holding tanks for recycling of liquid; wherein each of the at least 2 outlets in the base of the plenum is equipped with a fast-acting valve, each valve in communication with a conduit for draining liquid from the plenum to one of the at least two holding tanks; and wherein at least one of the valves has a domed upper surface, the dome extending above the level of the base of the plenum and the peripheral edges of the dome not sunken below the level of the surrounding plenum base.