The invention relates to an apparatus and process for filtering deposition gases in a substrate processing system. Particularly contemplated is an apparatus and process for the filtering deposition gases of a metal-oxide film deposited on a silicon wafer to make integrated circuits. In one embodiment, the invention provides an apparatus for filtering a fluid in a semiconductor processing system, comprising a housing and a filtering member disposable in the housing, the filtering member comprising a base portion and a filtering portion having an inlet and an outlet and a plurality of temperature controlled fluid passages formed between the inlet and the outlet, the passages having a length longer than a width across the passages.