MEMS switches with reduced switching voltage and methods of manufacture

• US 9,287,075 B2
• Filed: 03/27/2015
• Issued: 03/15/2016
• Est. Priority Date: 04/22/2008
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Luce, Stephen E., Stamper, Anthony K.
• Primary Examiner(s): Talpalatski, Alexander
• Application Number:
  US14/670,671
• Publication Number:
  US 20150200069A1
• Time in Patent Office: 354 Days
• Field of Search: 335/78
• US Class Current: 1/1
• CPC Class Codes: B81C 1/0015 Cantilevers switches using MEMS H01H1/0036; electrostatic relays using micromechanics H01H59/0009; microelectro-mechanical resonators H03H9/02244
• CPC Class Codes: B81C 1/00166 Electrodes
• CPC Class Codes: B81C 1/00523 Etching material
• CPC Class Codes: B81C 1/00698 Electrical characteristics, e.g. by doping materials
• CPC Class Codes: B81C 2201/0132 Dry etching, i.e. plasma etching, barrel etching, reactive ion etching [RIE], sputter etching or ion milling
• CPC Class Codes: B81C 2201/0133 Wet etching
• CPC Class Codes: B81C 2201/0135 Controlling etch progression
• CPC Class Codes: B81C 2201/0145 Spark erosion
• CPC Class Codes: B81C 2201/0154 other processes for film patterning not provided for in B81C2201/0149 - B81C2201/015
• CPC Class Codes: B81C 2203/0145 Hermetically sealing an opening in the lid
• CPC Class Codes: H01H 1/0036 Switches making use of microelectromechanical systems [MEMS] for electromagnetic relays H01H50/005; for electrostatic relays H01H59/0009
• CPC Class Codes: H01H 1/58 Electric connections to or between contacts; Terminals for high tension switches H01H33/025; for electromagnetic relays H01H50/14; for circuit breakers H01H71/08
• CPC Class Codes: H01H 1/66 Contacts sealed in an evacuated or gas-filled envelope, e.g. magnetic dry-reed contacts
• CPC Class Codes: H01H 11/00 Apparatus or processes specially adapted for the manufacture of electric switches processes specially adapted for manufacture of rectilinearly movable switches having a plurality of operating members associated with different sets of contacts, e.g. keyboards, H01H13/88
• CPC Class Codes: H01H 2059/0018 Special provisions for avoiding charge trapping, e.g. insulation layer between actuating electrodes being permanently polarised by charge trapping so that actuating or release voltage is altered
• CPC Class Codes: H01H 49/00 Apparatus or processes specially adapted to the manufacture of relays or parts thereof
• CPC Class Codes: H01H 50/005 using micromechanics
• CPC Class Codes: H01H 59/00 Electrostatic relays; Electro-adhesion relays
• CPC Class Codes: H01H 59/0009 making use of micromechanics
• CPC Class Codes: Y10T 29/49105 Switch making

Abstract

MEMS switches and methods of manufacturing MEMS switches is provided. The MEMS switch having at least two cantilevered electrodes having ends which overlap and which are structured and operable to contact one another upon an application of a voltage by at least one fixed electrode.

Claims

1. A structure comprising:

at least two fixed electrodes including a first fixed electrode and a second fixed electrode; and

at least three cantilevered electrodes including a first electrode, a second electrode, and a third electrode, wherein;

the first electrode and the second electrode overlap and are structured and operable to contact one another upon an application of a voltage to at least one fixed electrode;

the third electrode is a stationary electrode and is configured to provide a voltage to move the first electrode toward the second electrode;

the first fixed electrode is configured to apply the voltage which moves the first electrode towards the second electrode; and

the second fixed electrode is configured to apply another voltage which attracts the second electrodes toward the first electrode.

2. The structure of claim 1, wherein the second fixed electrode is raised higher than the first fixed electrode.

3. The structure of claim 2, wherein the first electrode or the second electrode includes a vertically extending portion that decreases a travel distance between the first electrode and the second electrode.

4. The structure of claim 3, further comprising a hermetically sealed volume having encapsulated therein the at least three cantilevered electrodes and the at least two fixed electrodes.