A method and apparatus for reflowing a material layer is provided. The inventive method introduces into a reflow chamber a material which is at least as reactive or more reactive than a material to be reflowed (i.e., a gettering material). Preferably the gettering material is sputter deposited within the reflow chamber while a shield prevents the gettering material from reaching the material layer to be reflowed. The shield may be coupled to, or integral with a clamp for clamping a wafer (containing the material layer to be reflowed) to a wafer support provided sufficient venting exists so that contaminants degassed from the wafer may flow to the region between the sputtering target and the shield where the contaminants can react with gettering material. The shield may have a roughened top surface (the surface that faces the sputtering target) which deters gettering material from flaking off the shield and/or the shield may have a reflective bottom surface (the surface that faces the wafer) that reflects heat to the wafer.