Process kit for uniformity control edge critical dimension

Adjustable ring assembly, a method for adjusting plasma processing chamber having an adjustable ring assembly, and a plasma process is provided. In one embodiment, the adjustable ring assembly includes a exposed upper surface, and an outer ceramic ring having a bottom surface configured to engage an outer ceramic ring, whereby inside the silicon ring defining an overlap region there, the inner silicon ring has an inner surface, an upper surface and a notch formed between the inner surface and the upper surface, the inner surface defines the inner diameter of the ring assembly, the notch accepts the edge of the substrate in size, the outer portion of the upper surface of the inner silicon ring, in the overlap region, is under the interior portion of the bottom surface of the outer ceramic ring, and an inner silicon ring configured to contact.