Mems switches with reduced switching voltage and methods of manufacture

Patent metadata

Field	Value
Publication number	US-2016145097-A1
Application number	US-201615012314-A
Country	US
Kind code	A1
Filing date	Feb 1, 2016
Priority date	Apr 22, 2008
Publication date	May 26, 2016
Grant date	—

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.

First claim

It is claimed:

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).

Assignees

• IBM

Inventors

• Luce Stephen E
• Stamper Anthony K

Classifications

• Y10T29/49105

  Switch making · CPC title

• H01H1/58

  Electric connections to or between contacts; Terminals {(for high tension switches H01H33/025; for electromagnetic relays H01H50/14; for circuit breakers H01H71/08)} · CPC title

• H01H59/0009 Primary

  making use of micromechanics · CPC title

• B81C1/00698 Primary

  Electrical characteristics, e.g. by doping materials · CPC title

• H01H2059/0018

  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 title