Embodiments of methods and apparatus for processing a substrate are provided herein. In some embodiments, a method of treating a substrate includes placing a substrate onto one of a plurality of substrate holders of a movable substrate carrier within a non-vacuum enclosure of a substrate treatment apparatus; heating the interior of the non-vacuum enclosure; supplying a gas into the non-vacuum enclosure to react with a surface of the substrate; and exhausting the gas from the non-vacuum enclosure through a vent in the non-vacuum enclosure.