Asymmetric pedestal/carrier ring arrangement for edge impedance modulation

摘要

Pedestal assemblies and methods for using said pedestal assemblies, used in processing chambers implemented for processing substrates are disclosed. In one example, the pedestal assembly includes a center column coupled to a lower chamber body of a processing chamber. A pedestal body is coupled to the center column. The pedestal body includes a substrate support surface and an annular step formed around a circumference of the pedestal body and surrounding the substrate support surface. Further included is a first annular ring segment disposed within the annular step. The first annular ring is defined from a conductive material. A second annular ring segment is also disposed within the annular step. The second annular ring is defined from a dielectric material. The first annular ring and the second annular ring fill the annular step around the circumference of the pedestal body. The first and second annular rings provide a fill that surrounds the substrate support and acts to modify an impedance for improving azimuthal uniformity of films deposited over the substrate using the processing chamber.