Applied Materials, Inc.
POLISHING SYSTEM WITH CONTACTLESS PLATEN EDGE CONTROL

Abstract:

A polishing system includes a platen having a top surface to support a main polishing pad. The platen is rotatable about an axis of rotation that passes through approximately the center of the platen. An annular flange projects radially outward from the platen to support an outer polishing pad. The annular flange has an inner edge secured to and rotatable with the platen and vertically fixed relative to the top surface of the platen. The annular flange is vertically deflectable such that an outer edge of the annular flange is vertically moveable relative to the inner edge. An actuator applies pressure to an underside of the annular flange in an angularly limited region, and a carrier head holds a substrate in contact with the polishing pad and is movable to selectively position a portion of the substrate over the outer polishing pad.