Electrostatic chuck with multi-zone control

摘要

An electrostatic chuck for clamping a warped workpiece has a clamping surface comprising a dielectric layer. The dielectric layer has a field and one or more zones formed of differing dielectric materials. One or more electrodes are coupled to a power supply, and a controller controls a clamping voltage supplied to the one or more electrodes via the power supply. An electrostatic attraction force associated with each of the field and one or more zones of the dielectric layer of the electrostatic chuck is induced, wherein the electrostatic attraction force varies based on the dielectric material of each of the field and one or more zones. The electrostatic attraction force is greater in the one or more zones than in the field, therein attracting warped regions of the workpiece to the clamping surface and clamping the warped workpiece to the clamping surface across a surface of the warped workpiece.

主权项

1. An electrostatic chuck, comprising:
a clamping surface comprising a dielectric layer, wherein the dielectric layer comprises a field and a plurality of zones defined therein, wherein the plurality of zones comprise a central zone associated with a center of the clamping surface and a peripheral zone associated with a periphery of the clamping surface, wherein the field is comprised of a first dielectric material, and wherein the plurality of zones are comprised of a second dielectric material, wherein each of the first dielectric material and second dielectric material have different dielectric constants associated therewith, and wherein one or more of the central zone and peripheral zone comprises a plurality of islands of the second dielectric material; and one or more electrodes associated with the dielectric layer, wherein a voltage supplied to the one or more electrodes is configured to induce an electrostatic attraction force associated with each of the field and plurality of zones, and wherein the electrostatic attraction force varies based on the dielectric material of each of the field and plurality of zones.