Patent ID: 8298344

Claim:
A processing method of processing a workpiece comprising the steps of: placing the workpiece in a processing system comprising: a processing vessel having a vessel body defining a processing space for receiving the workpiece and processing the same therein, and a lid for covering an opening formed in the vessel body to seal the processing space, the processing space being surrounded by a low-pressure space setable at a pressure lower than that of the processing space; a first sealing member sealing a joint between a part of the vessel body and a part of the lid to separate the low-pressure space from the processing space; and a second sealing member sealing a joint between a part of the vessel body and a part of the lid on the outer side of the first sealing member to separate the low-pressure space from an external space surrounding the processing vessel, the second sealing member being a resilient lip sealing member, by carrying the workpiece through the opening; covering the opening by the lid of the processing vessel to close the processing space, and creating a normally sealed state where the external space surrounding the processing vessel, the low-pressure space, and the processing space are isolated from each other with each having its own pressure; evacuating the low-pressure space to a pressure such that when the processing space and the low-pressure space communicate with each other due to an internal leakage state, the pressure in the processing vessel is not higher than the pressure in the external space; and processing the workpiece placed in the processing space.