US Patent 7649729 Electrostatic chuck assembly

The present invention generally comprises an electrostatic chuck base, an electrostatic chuck assembly, and a puck for the electrostatic chuck assembly. Precisely etching a substrate within a plasma chamber may be a challenge because the plasma within the chamber may cause the temperature across the substrate to be non-uniform. A temperature gradient may exist across the substrate such that the edge of the substrate is at a different temperature compared to the center of the substrate. When the temperature of the substrate is not uniform, features may not be uniformly etched into the various layers of the structure disposed above the substrate. A dual zone electrostatic chuck assembly may compensate for temperature gradients across a substrate surface.