Apparatus for foam-assisted wafer cleaning with use of universal fluid supply unit

An apparatus for foam-assisted wafer cleaning, comprising:

• a closable container having an interior, a cover that can be opened or removed, and a funnel-shaped base plate that has a foam outlet opening, a periphery, and a tapered surface that tapers radially outward from aforementioned foam-outlet opening toward the aforementioned periphery, said funnel-shaped plate forming together with the semiconductor wafer a funnel-shaped working chamber;
• a wafer-gripping mechanism for supporting the semiconductor wafer to be treated in a cleaning position, in which at least one funnel-shaped space is formed between the semiconductor wafer in said cleaning position, the center of the semiconductor wafer being coaxial with the center of the foam outlet opening in the base plate, and a distance from the base plate to the aforementioned surface of the wafer gradually decreasing from the foam-outlet opening toward the periphery;
• a fluid supply unit connected to the aforementioned central opening;
• a foam generator formed in the fluid supply unit and intended for converting cleaning liquid into foam;
• a cleaning-liquid source that contains a foamable cleaning liquid and is connected to the foam generator;
• and
• a source of pressurized neutral gas connected to the funnel-shaped working chamber through the foam generator, the aforementioned foam generator comprising a foam-generating-and-directing chamber that may be filled with a foamable cleaning liquid, a deflector located in said foam-generating-and-directing chamber capable of deflecting flows of pressurized neutral gas to the foamable cleaning liquid, and at least one gas-ejecting channel connected to said source of pressurized neutral gas for directing the flow of pressurized neutral gas onto the aforementioned deflector for creating in said foamable cleaning liquid a zone of reduced pressure where gas bubbles form and then produce foam.