Abstract: Methods and apparatus for processing a substrate are provided herein. For example, an apparatus for processing a substrate comprises a process chamber configured to process a substrate, a substrate support comprising a heat sink configured to cool the substrate support during operation and a water trap panel comprising a pumping ring configured to cool the water trap panel such that the water trap panel condenses water vapor molecules and drops a process chamber pressure during operation, and a chiller operably coupled to the substrate support and configured to supply a cooling fluid to the substrate support via a cooling fluid line that connects to the heat sink and the pumping ring via a serial configuration or a parallel configuration.