| 20090122458 | EMBOSSED ELECTROSTATIC CHUCK - An electrostatic chuck includes a layer having a plurality of protrusions to support a workpiece, wherein at least a portion of the layer has a first plurality of the plurality of protrusions. The first plurality of protrusions is spaced to geometrically form a pattern of hexagons. The first plurality of protrusions may be spaced an equal distance from adjacent protrusions and the equal distance may be about 4.0 millimeters from a center of one protrusion to a center of another protrusion. The present disclosure reduces peak mechanical stress levels conventionally present along an edge of each protrusion. Reducing such mechanical stress levels helps reduce backside damage to a supported workpiece, which in turn can reduce the generation of unwanted particles caused by such damage. | 05-14-2009 |
