Valve and micropump incorporating said valve

摘要

PCT No. PCT/EP91/01240 Sec. 371 Date Mar. 4, 1992 Sec. 102(e) Date Mar. 4, 1992 PCT Filed Jul. 3, 1991 PCT Pub. No. WO92/01160 PCT Pub. Date Jan. 23, 1992.A valve is formed by machining a silicon wafer 18 bonded to a glass wafer 2. This machining forms a membrane 44 and a sealing ring. Part of the surface of the membrane 44 and optionally the sealing ring are oxidized in order to impart a mechanical pre-tension to the membrane holding the valve in a closed position. Further etching 52 may be carried out in a manner such that in the absence of the aforesaid pre-tension the valve is in the open position at rest.