Clamping wafer holder for chemical-mechanical planarization machines and method for using it

Abstract

A clamping wafer holder for chemical - mechanical planarization ("CMP") machines is provided. It comprises a plate having a surface for receiving on it the wafer, and a retainer around the surface. The retainer includes at least two jaws shaped and arranged such that they define a recess with the surface. The wafer is placed in the recess. An actuator is coupled with the retainer and adjusts it from an open position where the jaws are separated from each other, to a closed position where the jaws clamp an edge portion of the wafer. When the retainer is in the closed position the jaws preferably contact each other and define a continuous cylindrical inner surface. The surface can have a stopper that engages a flat zone of a wafer. Where the shape of the jaws does not match exactly the periphery of the wafer, elastic inserts are mounted on the jaws. A vacuum source is coupled with the plate, to hold the wafer in the holder during reorientation. The actuator is advantageously operated by the vacuum source. Since the wafer is supported stably, it does not shift laterally within the recess, which reduces uneven polishing.

Dependencies are inferred from the claim text.