Apparatus and methods to promote wafer edge temperature uniformity

A processing chamber comprising:

• a chamber body;
• a liner disposed within the chamber body, the liner including a heater;
• a substrate support enclosed within the chamber body, the substrate support including a support surface configured to receive a substrate, and movable between a raised position and a lowered position;
• a purge ring disposed on the substrate support, the purge ring including a lower surface below a level of the support surface and an upper surface above the level of the support surface;
• and
• a shadow ring including a plurality of apertures, each aperture extending from a corresponding upper opening at an upper surface of the shadow ring to a corresponding lower opening at a lower surface of the shadow ring;
• wherein:
• when the substrate support is in the raised position, the shadow ring is disposed on the purge ring such that the lower surface of the shadow ring contacts the upper surface of the purge ring, and the purge ring blocks the plurality of apertures;
• and
• when the substrate support is in the lowered position, the shadow ring is disposed on the liner.