Mitsuhiro Shikida

Electrostatically driven gas valve with high conductance

The characteristics of a gas valve driven by electrostatic force are investigated. The gas valve consists of a pair of planar electrodes with a conductive film between them. Three valve ports pass through the electrode plates. The film is elastically bent in an S-shape in the middle and the S-bend moves back and forth as voltage is alternately applied between the film and each electrode. This valve has a high conductance achieved by large vertical film displacement. The valve is suitable for rarefied gas control systems, such as the molecular beam epitaxy (MBE) apparatus, which requires a gas flow rate on the order of 1 sccm under a low pressure of less than 100 Pa. Experimental models of the gas valve are constructed to investigate the valves operation. The maximum pressure difference the valve can handle depends on the applied voltage and the size of the port orifice. A valve with 2.0 mm inlet and outlet ports can work under the operating condition of the MBE apparatus. >