Arc resistant high voltage micromachined electrostatic switch
Goodwin, S. (2000). IPC No. U.S.Arc resistant high voltage micromachined electrostatic switch (Patent No. 6057520.)
A MEMS (Micro Electro Mechanical System) electrostatically operated device is provided that can switch high voltages while providing improved arcing tolerance. The MEMS device comprises a microelectronic substrate, a substrate electrode, first and second contact sets, an insulator, and a moveable composite. The moveable composite overlies the substrate and substrate electrode. In cross section, the moveable composite comprises an electrode layer and a biasing layer. In length, the moveable composite comprises a fixed portion attached to the underlying substrate, a medial portion, and a distal portion moveable with respect to the substrate electrode. Each contact set has at least one composite contact attached to the moveable composite, and preferably at least one substrate contact attached to the substrate. One of the contact sets is closer to the composite distal portion. The distal and/or medial portions of the moveable composite are biased in position when no electrostatic force is applied. Applying a voltage between the substrate electrode and moveable composite electrode creates an electrostatic force that attracts the moveable composite to the underlying substrate. The first and second contact sets are electrically connected when the distal portion of the moveable composite is attracted to the substrate. Once electrostatic force is removed, the moveable composite reassumes the biased position such that the first and second contact sets are disconnected in a sequence to minimize arcing. Various embodiments and methods of using the electrostatic MEMS device are provided.