Patent ID: 7430893

Claim:
A method for detecting contaminants in a gas flow in a semiconductor processing facility, using a gas sampling unit, said method comprising the steps of: providing a gas sampling unit comprising an entry manifold for dividing said gas flow into at least a first sample flow and a second sample flow; an exit manifold having an input end for receiving said at least the first sample flow and the second sample flow after passing through a plurality of sampling devices, and an output end, wherein the plurality of sampling devices comprises a first dry sampling device and a second sampling device; a first wet impinger having an input coupled to at least the first or the second sample flow on the entry manifold, said first wet impinger further having an output; and a second wet impinger having an input coupled to said output of said first wet impinger and further having an output coupled to the exit manifold; receiving a gas flow associated with a semiconductor processing tool, the gas flow containing at least one contaminant; dividing said gas flow into a first sample flow and a second sample flow; passing said first sample flow through a first dry sampling device for detecting said contaminant; passing the second sample flow through a second sampling device; and determining a contaminant within the gas flow.