Microelectro mechanical system switch

• US 20040173872A1
• Filed: 11/13/2003
• Published: 09/09/2004
• Est. Priority Date: 11/18/2002
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Song, In-sang, Park, Young-jun, Han, In-taek
• Granted Patent: US 6,960,971 B2
• Time in Patent Office: Days
• US Class Current: 257/528
• CPC Class Codes: B81B 2201/018 Switches not provided for in B81B2201/014 - B81B2201/016
• CPC Class Codes: B81B 3/0008 Structures for avoiding electrostatic attraction, e.g. avoiding charge accumulation
• CPC Class Codes: H01H 59/0009 making use of micromechanics

Abstract

Provided is a microelectro mechanical system (MEMS). The provided MEMS switch includes a substrate; a signal line formed on the substrate; a beam deformed by an electrostatic force to electrically switch with the signal line; and a spring type contact unit formed on the signal line to electrically contact the beam and elastically deformed by an external force. Thus, stability of the contact between the contact unit and the beam is improved. In particular, even when the beam or the contact unit under the beam is unbalanced, the contact unit can elastically contact the beam to obtain a stable electrical switching operation.

Claims

1. A microelectro mechanical system (MEMS) switch comprising:

a substrate;

a signal line formed on the substrate;

a beam deformed by an electrostatic force to electrically switch with the signal line; and

a spring type contact unit formed on the signal line to electrically contact the beam and elastically deformed by an external force.

2. The MEMS switch of claim 1, wherein the contact unit is formed as a curved flip spring.

3. The MEMS switch of claim 1, wherein the contact unit is formed as a dome shape having a top portion corresponding to the beam.

4. The MEMS switch of claim 1, wherein the contact unit is formed into an arch shape having end units.

5. The MEMS switch of claim 1, wherein the contact unit is formed of amorphous silicon.

6. The MEMS switch of claim 1, wherein a through hole is formed at a top portion of the dome-shape contact unit.

7. The MEMS switch of claim 3, wherein a through hole is formed at a top portion of the dome-shape contact unit.

8. The MEMS switch of claim 1, wherein the beam is suspended by spacers that support the beam by being formed at both sides of the beam.

9. The MEMS switch of claim 8, wherein the beam is arranged to be perpendicular to the signal line, and beam driving electrodes are arranged under the beam and at the both sides of the signal line.

10. The MEMS switch of claim 8, wherein dielectric layers are formed on the beam driving electrodes.

11. The MEMS switch of claim 1, wherein a rear end of the beam is fixed by a spacer formed on the substrate, and a front end of the beam is located above the contact unit of the signal line.

12. An MEMS switch comprising:

a substrate;

first and second signal lines formed on the substrate while the ends of the signal lines are adjacent;

a beam deformed by electrostatic force to electrically contact the first and second signal lines; and

spring type contact units arranged at both ends of the signal lines to electrically connect to the beam and electrically deformed by an external force.

13. The MEMS switch of claim 12, wherein the contact units formed at the both ends of the first and second signal lines are formed as curved flip springs.

14. The MEMS switch of claim 12, wherein the contact units are formed of amorphous silicon.

15. The MEMS switch of claim 12, wherein the beam is suspended by spacers that support the beam by being formed at both sides of the beam.

16. The MEMS switch of claim 15, wherein the beam is arranged to be perpendicular to the first and second signal lines, and beam driving electrodes are arranged under the beam and at the both sides of the signal lines.

17. The MEMS switch of claim 15, wherein dielectric layers are formed on the beam driving electrodes.

18. The MEMS switch of claim 12, wherein a rear end of the beam is fixed by a spacer formed on the substrate, and a front end of the beam is located above the contact units of the first and second signal lines.