Micro-electromechanical switch

• US 6,307,169 B1
• Filed: 02/01/2000
• Issued: 10/23/2001
• Est. Priority Date: 02/01/2000
• Status: Expired due to Term

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Sun, Xi-Qing, Parsey, Jr., John Michael, Huang, Jenn-Hwa, Xu, Ji-Hai
• Primary Examiner(s): Scott, J. R.
• Application Number:
  US09/495,664
• Time in Patent Office: 630 Days
• Field of Search: 200/181, 361/233, 333/101-108, 333/262, 735/140.1, 735/143.9, 257/414-420
• US Class Current: 200/181
• CPC Class Codes: B81B 2201/018 Switches not provided for in B81B2201/014 - B81B2201/016
• CPC Class Codes: B81B 2203/0361 Tips, pillars
• CPC Class Codes: B81B 3/0008 Structures for avoiding electrostatic attraction, e.g. avoiding charge accumulation
• CPC Class Codes: H01H 2001/0089 Providing protection of elements to be released by etching of sacrificial element; Avoiding stiction problems, e.g. of movable element to substrate
• CPC Class Codes: H01H 2059/0054 Rocking contacts or actuating members
• CPC Class Codes: H01H 2059/0072 with stoppers or protrusions for maintaining a gap, reducing the contact area or for preventing stiction between the movable and the fixed electrode in the attracted position
• CPC Class Codes: H01H 59/0009 making use of micromechanics
• CPC Class Codes: H01P 1/12 by mechanical chopper

Abstract

A Micro-Electromechanical System (MEMS) switch (100) having a single, center hinge (120) which supports a membrane-type electrode (104) on a substrate (101). The single, center hinge (120) has a control electrode (104) coupled to the substrate (101) by an anchor (113), a hinge collar (121), a set of hinge arms (122, 123). The control electrode (104) has a shorting bar (106) coupled thereto and is electrically isolated from another control electrode (105), which is formed on the substrate (101). A travel stop (130) is positioned between the substrate and the control electrode (104). Another aspect of the present invention is a Single Pole, Double Throw (SPDT) switch (160) into which is incorporated the single, center hinge (170) and the travel stop (185, 186).

Claims

1. A Micro Electro-Mechanical System (MEMS) switch, comprising:

a substrate;

a first control electrode disposed on the substrate;

a single, center hinge extending from the substrate; and

a second control electrode coupled to the single, center hinge and electrically isolated from the first control electrode wherein the single, center hinge comprises, an anchor having a hinge collar coupled to the anchor, and at least one hinge arm coupled to the hinge collar and coupled to the second control electrode.

2. The MEMS switch of claim 1, further including a shorting bar coupled to the second control electrode.

3. The MEMS switch of claim 1, wherein the at least one hinge arm comprises two hinge arms and wherein a first of the two hinge arms is coupled to one side of the hinge collar and a second of the two hinge arms is coupled to a second side of the hinge collar.

4. The MEMS switch of claim 1, further including a plurality of interconnect structures disposed on the substrate, wherein the plurality of interconnect structures are electrically isolated from each other and from the first and second control electrodes when the MEMS switch is in an open state.

5. The MEMS switch of claim 1, further including a control lead coupled to the second control electrode.

11. The MEMS switch of claim 1, wherein the second control electrode comprises a layer of an electrically nonconductive material and a layer of an electrically conductive material.

12. The MEMS switch of claim 11, further including a shorting bar disposed on the layer of the electrically nonconductive material.

6. A Micro Electro-Mechanical System (MEMS) switch, comprising:

a substrate;

a first control electrode disposed on the substrate;

a single, center hinge extending from the substrate;

a second control electrode coupled to the single, center hinge and electrically isolated from the first control electrode; and

at least one travel stop for limiting movement of the second control electrode.

7. The MEMS switch of claim 6, wherein the at least one travel stop is located between the first control electrode and the single, center hinge.

8. The MEMS switch of claim 6, wherein the at least one travel stop is coupled to the second control electrode.

9. The MEMS switch of claim 6, wherein the at least one travel stop is coupled to the substrate.

10. The MEMS switch of claim 6, wherein the at least one travel stop is comprised of two travel stops, one of the two travel stops between the first control electrode and the single, center hinge and a second of the two travel stops located proximal to an end of the second control electrode.

13. A Single Pole, Double Throw (SPDT) Micro-electromechanical (MEMS) switch, comprising:

a substrate;

first and second control electrodes coupled to the substrate, wherein the first and second control electrodes are electrically isolated from each other;

a single, center hinge extending from the substrate; and

third and fourth control electrodes coupled to the single, center hinge and electrically isolated from the first and second control electrodes.

14. The SPDT MEMS switch of claim 13, further including a first shorting bar coupled to the third control electrode and a second shorting bar coupled to the fourth control electrode, the first shorting bar for contacting the first control electrode and the second shorting bar for contacting the second control electrode.

15. The SPDT MEMS switch of claim 13, further including at least one travel stop.

16. The SPDT MEMS switch of claim 15, wherein the at least one travel stop comprises a first travel stop for limiting movement of the third control electrode and a second travel stop for limiting movement of the fourth control electrode.

17. The SPDT MEMS switch of claim 13, wherein the at least one travel stop is disposed on the substrate.

18. The SPDT MEMS switch of claim 13, wherein the single, center hinge further comprises:

an anchor;

a hinge collar coupled to the anchor; and

at least one hinge arm coupled to the hinge collar and coupled to the upper control electrode.