Method of manufacturing MEMS switches with reduced switching volume

Patent metadata

Field	Value
Publication number	US-9944517-B2
Application number	US-201514883745-A
Country	US
Kind code	B2
Filing date	Oct 15, 2015
Priority date	Apr 22, 2008
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

An approach includes a method of fabricating a switch. The approach includes forming a first fixed electrode and a second fixed electrode, forming a first cantilevered electrode aligned vertically over the first fixed electrode, forming a second cantilevered electrode aligned vertically over the second fixed electrode, and which has an end that overlaps and is operable to directly contact an end of the first cantilevered electrode upon an application of a voltage to at least one of the first fixed electrode and the second fixed electrode, and forming a hermetically sealed volume encapsulating the first fixed electrode, the second fixed electrode, the first cantilevered electrode, and the second cantilevered electrode.

First claim

It is claimed:

1. A method of fabricating a switch comprising:
forming a first fixed electrode and a second fixed electrode;
forming a first cantilevered electrode aligned vertically over the first fixed electrode;
forming a second cantilevered electrode aligned vertically over the second fixed electrode, and which has an end that overlaps and is operable to directly contact an end of the first cantilevered electrode upon an application of a voltage to at least one of the first fixed electrode and the second fixed electrode; and
forming a hermetically sealed volume encapsulating the first fixed electrode, the second fixed electrode, the first cantilevered electrode, and the second cantilevered electrode,
wherein the first cantilevered electrode comprises an arm with an extending protrusion which extends upward from an upper surface of the arm.

2. The method of claim 1 , wherein the hermetically sealed volume is a dome.

3. The method of claim 2 , wherein the dome is oval shaped.

4. The method of claim 1 , wherein overlapping portions of the first cantilevered electrode and the second cantilevered electrode are separated by a vertical distance of about two microns.

5. The method of claim 1 , wherein the second cantilevered electrode is formed above the first cantilevered electrode.

6. The method of claim 1 , wherein the hermetically sealed volume comprises nitride.

7. The method of claim 1 , wherein the second cantilevered electrode is operable to directly contact the end of the first cantilevered electrode upon a positive voltage applied to the second fixed electrode.

8. The method of claim 7 , wherein the positive voltage is about 30 volts.

9. The method of claim 1 , wherein a height of the second fixed electrode is higher than a height of first fixed electrode.

10. A method of fabricating a switch comprising:
forming a first fixed electrode and a second fixed electrode;
forming a first cantilevered electrode aligned vertically over the first fixed electrode;
forming a second cantilevered electrode aligned vertically over the second fixed electrode, and which has an end that overlaps and is operable to directly contact an end of the first cantilevered electrode upon an application of a voltage to at least one of the first fixed electrode and the second fixed electrode; and
forming a hermetically sealed volume encapsulating the first fixed electrode, the second fixed electrode, the first cantilevered electrode, and the second cantilevered electrode,
wherein the forming the hermetically sealed volume comprises:
forming at least one hole in a nitride liner to gain access to a sacrificial resist;
etching the sacrificial resist; and
closing the at least one hole by deposition of additional liner material.

Assignees

• IBM

Inventors

• Luce Stephen E
• Stamper Anthony K

Classifications

• B81C2201/0154

  other processes for film patterning not provided for in B81C2201/0149 - B81C2201/015 · CPC title

• H01H49/00

  Apparatus or processes specially adapted to the manufacture of relays or parts thereof · CPC title

• B81C2201/0133

  Wet etching · CPC title

• H01H59/0009 Primary

  making use of micromechanics · CPC title

• H01H50/005

  using micromechanics · CPC title