Patent ID: 8795479
Filing Date: 2014-08-05
Classification: C23C,H01L

Abstract:
1. A wafer clamp for holding a wafer during a semiconductor fabrication process, said wafer clamp comprising: a wafer clamp assembly having a step that defines a depression with a substantially flat, exposed surface, wherein the wafer clamp assembly is annular and the step is also annular; a plurality of substantially flat finger members mounted in the depression on the substantially flat, exposed surface, each substantially flat finger member having: an outer annular member coupled to: and a central recess defined by the first annular projection, wherein the central recess has a diameter that is greater than d, the diameter of the wafer, wherein the wafer can be clamped so that the wafer is not contacted by the outer annular member during a deposition process, wherein the contact portion of each finger member overhangs the wafer to be clamped only at selected areas, and wherein the finger members contact the wafer only at the selected areas where the finger members overhang the wafer, thereby reducing an edge exclusion of the wafer, wherein the contact portion has a hemispherical shape thereby establishing a point contact surface with the wafer, wherein the contact portion is immobile relative to the finger; and a first screw within the first annular projection and a second screw in the second annular projection.