Extended range diaphragm valve and method for making same

摘要

An improved micro-machined valve assembly includes a valve diaphragm that will not adhere to a valve seat during elevated temperature operation. In one embodiment, a portion of the diaphragm that is susceptible to adhering to the valve seat at elevated temperature is removed in the region where the diaphragm contacts the valve seat. In another embodiment, the valve diaphragm includes a metal layer applied to the portion of the diaphragm that comes into contact with the valve seat during operation of the valve. The metal layer extends the operating temperature of the valve by preventing adhesion of the diaphragm to the valve seat during high temperature operation. Selection of an appropriate material for the metal layer can improve chemical inertness of valve, thereby reducing the possibility that the material flowing through the valve will react with the metal.