Method of manufacturing a switch

• US 9,718,681 B2
• Filed: 02/01/2016
• Issued: 08/01/2017
• Est. Priority Date: 04/22/2008
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Stamper, Anthony K., Luce, Stephen E.
• Primary Examiner(s): PHAN, THIEM D
• Application Number:
  US15/012,314
• Publication Number:
  US 20160145097A1
• Time in Patent Office: 547 Days
• Field of Search: 29622, 29825, 29829, 29846, 29874
• 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 method of forming a switch, comprising:

depositing layers of resist on a structure;

patterning the resist to form sequential openings;

sequentially depositing metal or metal alloy within the sequential openings until at least two cantilever electrodes and at least one voltage applying electrode are formed within the layers of resist;

depositing a liner over an uppermost layer of the layers of resist;

forming openings in the liner;

etching the layers of the resist through the opening until the cantilever electrodes and the at least one voltage applying electrode are in a void; and

sealing the void with additional liner material to form a hermetically sealed dome.

2. The method of claim 1, wherein the liner is a nitride liner and the openings in the liner are filled with additional nitride.

3. The method of claim 1, wherein the liner is deposited on a portion of one of the at least two cantilever electrodes thereby fixing the one of the at least two cantilever electrodes to the liner.

4. The method of claim 3, wherein the one of the at least two cantilever electrodes fixed to the liner is stationary.

5. The method of claim 1, further comprising sequentially depositing metal or metal alloy within the sequential openings until at least three cantilever electrodes are formed within the layers of resist, wherein a first of the cantilever electrodes is configured to apply a voltage to move a second of the cantilever electrodes towards a third of the cantilever electrodes, the second and the third cantilever electrodes being formed to be moveable.

6. The method of claim 5, further comprising forming a vertically extending portion on at least one of the second of the cantilever electrodes or the third of the cantilever electrodes to reduce a travel distance between the second of the cantilever electrodes and the third of the cantilever electrodes.

7. The method of claim 1, wherein two cantilever electrodes of the at least two cantilever electrodes overlap with each other.

8. The method of claim 1, wherein upon application of a voltage to one voltage applying electrode of the at least one voltage applying electrode, two cantilevers of the at least two cantilevers are operable to directly contact each other.

9. The method of claim 8, wherein the voltage applied to the one voltage applying electrode of the at least one voltage applying electrode is about 100 V.

10. The method of claim 1, wherein the metal or the metal alloy sequentially deposited comprises Au.

11. The method of claim 1, wherein the metal or the metal alloy sequentially deposited comprises AlCu.

12. The method of claim 1, wherein the metal or the metal alloy sequentially deposited comprises W.

13. The method of claim 1, wherein the metal or the metal alloy sequentially deposited comprises Cu.

14. The method of claim 1, wherein the resist comprises polymethylglutarimide (PMGI).