Abstract: An electrostatic chuck for clamping workpieces having differing diameters is provided. A central electrostatic chuck member associated with a first workpiece and a first peripheral electrostatic chuck member associated with a second workpiece are provided. An elevator translates the first peripheral electrostatic chuck member with respect to central electrostatic chuck member between a retracted position and an extended position. In the retracted position, the first workpiece contacts only the first surface. In the extended position, the second workpiece contacts the first surface and the second surface. A first peripheral shield generally shields the second surface when the first peripheral electrostatic chuck member is in the retracted position. Additional peripheral electrostatic chuck members and peripheral shields can be added to accommodate additional workpiece diameters.

Abstract: A method for clamping a workpiece is provided, wherein a workpiece is placed on a surface of a clamping plate of a multi-polar electrostatic clamp having a plurality of electrodes. A plurality of phases of the AC clamping voltage are applied to the plurality of electrodes, wherein at least one of the plurality of phases of the AC clamping voltage applied to at least one of the plurality of electrodes is shifted with respect to the remaining plurality of phases by an offset phase shift. A fluctuation in clamping force between the clamping plate and the workpiece during a cycle of the at least one of the plurality of phases of AC clamping voltage is determined, and the offset phase shift is controlled, based, at least in part, on the determined fluctuation in clamping force, an RC time constant of the clamping system, and a set of performance criteria.

Abstract: A process for removing polymers formed during etching and etch residues from a semiconductor substrate by exposing the substrate to plasmas of neutral chemistry. The plasma generates atomic hydrogen species and atomic oxygen species in about equal amounts that react with and remove the polymers and etch residues from the substrate. The process is especially suitable for use with semiconductor substrates comprising low k dielectric materials and/or copper interconnects.