A substrate support may include a body; an inner ring disposed about the body; an outer ring disposed about the inner ring forming a first opening therebetween; a first seal ring disposed above the first opening; a shadow ring disposed above the inner ring, extending inward from the outer ring and forming a second opening between the shadow and outer rings; a second seal ring disposed above the second opening; a space at least partially defined by the body and the inner, outer, first, second, and shadow rings; a first gap defined between a processing surface of a substrate when present and the shadow ring; and a plurality of second gaps fluidly coupled to the space; wherein the first gap and the plurality of second gaps are configured such that, when a substrate is present, a gas provided to the space flows out of the space through the first gap.