Patent ID: 8088225

Claim:
A substrate support system, comprising: a substrate holder for holding a substrate, the substrate holder comprising: a central portion having an upper surface, a lower surface, and a plurality of passages extending from the upper surface to the lower surface; and at least one spacer extending upward from the central portion and having an upper support surface raised above the upper surface of the central portion, at least one spacer's upper support surface being configured to support the substrate so that a gap region exists between the upper surface of the central portion and a bottom surface of the substrate; and a hollow support spider comprising: a hollow manifold having an inlet adapted to engage an outlet of a gas-conveyor to facilitate gas flow from the gas-conveyor into the manifold; and a plurality of hollow arms extending generally radially outward and upward from the manifold, the hollow arms configured to receive gas flow from the manifold, the hollow arms having open upper ends adapted to support the lower surface of the central portion of the substrate holder, the open upper ends of the hollow arms configured to convey gas upward into some but not all of the passages of the central portion of the substrate holder; wherein the plurality of passages comprises a first set of passages configured to convey gas from the hollow arms to the gap region and a second set of passages configured to convey gas from the gap region to the lower surface of the substrate holder without conveying gas into the hollow arms.