Patent ID: 11919120
Assignee: APPLIED MATERIALS, INC.
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 17:
18. A polishing system, comprising:
an annular platen having a top surface to support a main polishing pad, the annular platen having an aperture in the top surface of the platen in approximately the center of the platen, the platen rotatable about an axis of rotation that passes through approximately the center of the platen;
an annular flange projecting radially inward from the platen into the aperture to support an inner polishing pad, the annular flange being a unitary body having an outer edge secured to and rotatable with the platen and vertically fixed relative to the top surface of the platen, the annular flange being deformable and vertically deflectable such that an inner edge of the annular flange is vertically movable relative to the outer edge;
a contactless actuator configured to apply pressure to an underside of the annular flange in an angularly limited region such that the angularly limited region of the annular flange and an angularly limited portion of the inner polishing pad are lifted relative to an undeformed portion of the annular flange without contacting the annular flange; and
a carrier head to hold a substrate in contact with the main polishing pad and movable to selectively position a portion of the substrate over the inner polishing pad.