Heat shield assemblies for minimizing heat radiation to pump of process chamber

A processing chamber, comprising:

• a chamber body defining an interior volume therein, wherein the chamber body includes a pump port configured for coupling the chamber body to a pump;
• a substrate support disposed in the interior volume and configured to support a substrate;
• and
• a heat shield assembly disposed in the interior volume proximate the pump port and substantially covering the pump port, the heat shield assembly comprising:
• a plurality of shields arranged in a parallel configuration, wherein a first shield of the plurality of shields comprises a circular plate, wherein a second shield of the plurality of shields has an outer diameter greater than an outer diameter of the first shield and the second shield includes a central opening having a diameter smaller than an outer diameter of the first shield, and wherein a third shield of the plurality of shields is a plate that has an outer diameter greater than a diameter of the central opening of the second shield.