Microelectromechanical high pressure gas microvalve

A microvalve and a method of forming a microvalve. The microvalve comprises first and second layers, a diaphragm member and a switching means. The first and second layers are secured together to form a valve body that forms an inlet opening for receiving fluid, an outlet opening for conducting fluid from the valve body, and a flow channel for conducting fluid from the inlet to the outlet. The diaphragm is disposed between the layers, and is movable between open and closed positions. In these position, the diaphragm, respectively, allows and blocks the flow of fluid from the inlet to the flow channel. The diaphragm is biased to the closed position, and moves from the closed position to the open position when the pressure of fluid in the inlet reaches a preset value. The switching means is connected to the valve body for moving the diaphragm to the closed position against the pressure of fluid in the inlet. Preferably, the microvalve is constructed out of SiC and stainless steel materials, allowing the microvalve to be used in a harsh environment.