Edge ring for a thermal processing chamber

1. An edge ring for supporting a substrate in a processing chamber, comprising:

a ring shaped body defined by an inner edge, an outer edge, an upper side and a lower side, wherein the inner edge and outer edge are concentric about a central axis;

a lip extending radially inward from the inner edge of the ring shaped body, wherein the upper surface of the lip is below an upper surface of the ring shaped body so that the lip and body form a recess for holding the substrate and at least a portion of an upper surface of the lip is configured to support a substrate around an outer edge of the substrate so that the substrate is substantially parallel to a major plane that is perpendicular to the central axis; and

one or more surface area increasing structures extending from at least one of the upper side or lower side of the ring shaped body, wherein the one or more surface area increasing structures comprises a fin extending from the lower side of the ring shaped body, the fin forms a circular wall concentric to the inner edge and the outer edge, the fin is positioned between the inner edge and the outer edge, the fin is disposed at the inner edge of the ring shaped body, and the lip extends from the fin.

2. The edge ring of claim 1 , wherein the lip is tilted at an angle relative to the major plane.

3. The edge ring of claim 1 , wherein the one or more surface area increasing structures are configured to face a radiant energy source.

4. The edge ring of claim 1 , further comprising a positioning rim extending from the ring shaped body.

5. The edge ring of claim 4 , wherein the positioning rim extends from the ring shaped body near the outer edge.

6. The edge ring of claim 1 , wherein the edge ring is formed from a silicon carbide material.

7. The edge ring of claim 1 , further comprising a second fin.