Disclosed are method and apparatus for treating a substrate. The apparatus is a dual-function process chamber that may perform both a material process and a thermal process on a substrate. The chamber has an annular radiant source disposed between a processing location and a transportation location of the chamber. Lift pins have length sufficient to maintain the substrate at the processing location while the substrate support is lowered below the radiant source plane to afford radiant heating of the substrate. One or more lift pins has a light pipe disposed therein to collect radiation emitted or transmitted by the substrate when the lift pin contacts the substrate surface.