# US 2014/0191616 A1 · Mems switch > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0191616 A1 - Document ID: US20140191616A1 - Status: Published application - Kind: A1 - Application number: 14/208,012 - Filed: 2014-03-13 - Published: 2014-07-10 - Earliest claimed: 2011-10-06 - Assignees: Fujitsu Limited - Applicants: Fujitsu Limited - Inventors: OSAMU TOYODA; Takeaki Shimanouchi - Web page: https://patentgrep.com/patent/US20140191616A1 ## CPC - H10N 30/2042: {Cantilevers, i.e. having one fixed end} - B81C 1/00976: {Control methods for avoiding stiction, e.g. controlling the bias voltage} - H01H 57/00: Electrostrictive relays; Piezoelectric relays - B81B 2201/016: having a bridge fixed on two ends and connected to one or more dimples - H01H 2057/006: {Micromechanical piezoelectric relay} - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - B81C: PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS (making microcapsules or microballoons B01J13/02; processes or apparatus specially adapted for the manufacture or treatment of piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/01) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) - B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00) ## Abstract A MEMS switch has fixed support, a plate-shaped flexible beam having at least one end immovably supported by the fixed support and having an extending movable surface, a movable electric contact disposed on the movable surface of the flexible beam, a fixed electric contact facing the movable electric contact and disposed at a fixed position relative to the fixed support, first piezoelectric driver disposed above the movable surface of the flexible beam, extending from a portion above the fixed support towards the movable electric contact, and capable of displacing the movable electric contact towards the fixed electric contact by voltage driving, and second piezoelectric driver disposed at least on the movable surface of the flexible beam and capable of so driving a movable part of the flexible beam by voltage driving that the movable electric contact is separated from the fixed electric contact. ## Claims ### Claim 1 A MEMS switch comprising: fixed support; a plate-shaped flexible beam having at least one end immovably supported by the fixed support and having an extending movable surface; a movable electric contact disposed on the movable surface of the flexible beam; a fixed electric contact facing the movable electric contact and disposed at a fixed position relative to the fixed support; first piezoelectric driver disposed above the movable surface of the flexible beam, extending from a portion above the fixed support towards the movable electric contact, and capable of displacing the movable electric contact towards the fixed electric contact by voltage driving; and second piezoelectric driver disposed at least on the movable surface of the flexible beam and capable of so driving a movable part of the flexible beam by voltage driving that the movable electric contact is separated from the fixed electric contact. ### Claim 2 (depends on 1) A MEMS switch according to claim 1, wherein either of the first piezoelectric driver and the second piezoelectric driver has a lower electrode, a piezoelectric material layer disposed on the lower electrode, and an upper electrode disposed on the piezoelectric material layer. ### Claim 3 (depends on 2) A MEMS switch according to claim 2, wherein the movable electric contact is disposed in an intermediate-width region of the flexible beam and the second piezoelectric driver includes a pair of piezoelectric actuators disposed on both outer-width sides of the the movable electric contact. ### Claim 4 (depends on 3) A MEMS switch according to claim 3, wherein the fixed support comprises an SCH substrate in which an active Si layer is bonded to an Si support substrate via a silicon oxide layer, and the flexible beam comprises part of the active Si layer and has a stripe shape having a constant width and extending in a longitudinal direction. ### Claim 5 (depends on 4) A MEMS switch according to claim 4, wherein the flexible beam has a both-ends supported beam structure and the movable electric contact and the second piezoelectric driver are disposed in an intermediate region between two ends of the both-ends supported beam. ### Claim 6 (depends on 4) A MEMS switch according to claim 4, wherein the flexible beam has a cantilever beam structure and the movable electric contact and second piezoelectric driver are disposed in vicinity of free end of the cantilever beam. ### Claim 7 (depends on 1) A MEMS switch according to claim 1, further comprising: a first control circuit that controls the first piezoelectric driver; and a second control circuit that controls the second piezoelectric driver. ### Claim 8 (depends on 7) A MEMS switch according to claim 7, wherein the first control circuit and the second control circuit are coupled through mutual induction. ### Claim 9 (depends on 7) A MEMS switch according to claim 7, further comprising a microprocessor that controls the first control circuit and the second control circuit. ### Claim 10 (depends on 9) A MEMS switch according to claim 9, further comprising a counter that counts number of operations of the first control circuit and the microprocessor activates the second control circuit once in response to a plural times of activation of the first control circuit.