Method and structure for a solid slug caterpillar piezoelectric relay

• US 20040201316A1
• Filed: 04/14/2003
• Published: 10/14/2004
• Est. Priority Date: 04/14/2003
• Status: Active Grant

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Fong, Arthur, Wong, Marvin Glenn
• Granted Patent: US 6,876,132 B2
• Time in Patent Office: Days
• US Class Current: 310/328
• CPC Class Codes: H01H 2029/008 using micromechanics, e.g. micromechanical liquid contact switches or [LIMMS]
• CPC Class Codes: H01H 2057/006 Micromechanical piezoelectric relay
• CPC Class Codes: H01H 57/00 Electrostrictive relays; Piezoelectric relays

Abstract

A method and structure for an electrical switch. A gas-filled chamber is housed within a solid material. Contacts within the gas-filled chamber are coupled to the solid material, while a plurality of piezoelectric elements within the gas-filled chamber are also coupled to the solid material. A slug within the gas-filled chamber is coupled to one or more of the plurality of contacts and further coupled to one or more of the plurality of piezoelectric elements. A liquid metal within the gas-filled chamber is coupled to the slug, and coupled to the plurality of contacts. One or more of the piezoelectric elements are actuated, with the actuation of the one or more piezoelectric elements causing the slug coupled to the one or more piezoelectric elements to move from a first number of contacts to a second number of contacts wherein the first number of contacts and the second number of contacts are wetted by the liquid metal. The movement of the slug from the first number of contacts to the second number of contacts breaks a liquid metal surface tension between the slug and the first number of contacts and establishes a coupling between the slug and the second number of contacts, thereby enabling the liquid metal switch to change from a first state to a second state.

Claims

1. A structure for an electrical switch, comprising:

a gas-filled chamber housed within a solid material;

a plurality of contacts within the gas-filled chamber, wherein the plurality of contacts are coupled to the solid material;

a plurality of piezoelectric elements within the gas-filled chamber, coupled to the solid material;

a slug within the gas-filled chamber coupled to one or more of the plurality of contacts and further coupled to one or more of the plurality of piezoelectric elements; and

a liquid metal coupled to the slug, and coupled to the plurality of contacts.

2. The structure of claim 1, wherein the plurality of piezoelectric elements are perpendicular to the plurality of contacts.

3. The structure of claim 1, wherein the slug is tapered at one or more ends.

4. The structure of claim 1, wherein the plurality of piezoelectric elements are segmented.

5. The structure of claim 1, wherein the plurality of piezoelectric elements are coupled to a common ground.

6. The structure of claim 1, further comprising a vent passage coupled to the gas-filled chamber, wherein the vent passage comprises one or more vent couplings to the gas-filled chamber.

7. The structure of claim 6, wherein the one or more vent couplings are oriented so that the plurality of piezoelectric elements are located between a first vent coupling of the one or more vent couplings and a second vent coupling of the one or more vent couplings.

8. The structure of claim 1, wherein the chamber is filled with an inert gas.

9. The structure of claim 8, wherein the gas is nitrogen.

10. The structure of claim 1, wherein the chamber further comprises one or more channels.

11. The structure of claim 10, wherein the one or more channels have the same orientation as the chamber.

12. The structure of claim 10, wherein one or more of the one or more channels are located adjacent to the one or more locations where the vent passage is coupled to the chamber.

13. The structure of claim 10, wherein one or more of the one or more channels are located at one or more ends of the plurality of piezoelectric elements.

14. The structure of claim 1, wherein the liquid metal is mercury.

15. The structure of claim 1, wherein the slug stays within a volume of the liquid metal during the actuation of one or more of the plurality of piezoelectric elements.

16. A structure for an electrical switch using a plurality of piezoelectric elements, comprising:

a cap layer;

a piezoelectric layer coupled to the cap layer;

a circuit substrate layer coupled to the piezoelectric layer; and

a gas-filled chamber coupled to one or more of the piezoelectric layer, cap layer and circuit substrate layer, wherein the gas-filled chamber further comprises the plurality of piezoelectric elements, a plurality of contacts, a slug coupled to one or more of the plurality of contacts and coupled to one or more of the plurality of piezoelectric elements, and a liquid metal coupled to the slug, and coupled to the plurality of contacts.

17. The structure of claim 16, wherein the cap layer, circuit substrate layer, piezoelectric layer may be composed of one or more of glass, ceramic, composite material and ceramic-coated material.

18. The structure of claim 16, further comprising a vent passage coupled to the gas-filled chamber, wherein the vent passage comprises one or more vent couplings to the gas-filled chamber.

19. The structure of claim 18, wherein the one or more vent couplings are oriented so that the plurality of piezoelectric elements are located between a first vent coupling of the one or more vent couplings and a second vent coupling of the one or more vent couplings.

20. The structure of claim 16, wherein the circuit substrate layer further comprises a plurality of circuit traces and a plurality of pads operable to route one or more signals generated by actuation of one or more of the plurality of piezoelectric elements.

21. The structure of claim 16, wherein the chamber is filled with an inert gas.

22. The structure of claim 16, wherein the chamber further comprises one or more channels.

23. The structure of claim 22, wherein one or more of the one or more channels are located at one or more ends of the plurality of piezoelectric elements.

24. The structure of claim 16, wherein the slug stays within a volume of the liquid metal during the actuation of one or more of the plurality of piezoelectric elements.

25. A method for electrical switching of one or more electrical signals using a liquid metal switch, comprising:

actuating one or more of a plurality of piezoelectric elements;

the actuation of the one or more piezoelectric elements causing a slug coupled to the one or more piezoelectric elements to move from a first number of contacts to a second number of contacts wherein the first number of contacts and the second number of contacts are wetted by a liquid metal; and

the movement of the slug from the first number of contacts to the second number of contacts breaking a liquid metal surface tension between the slug and the first number of contacts and establishing a coupling between the slug and the second number of contacts, thereby enabling the liquid metal switch to change from a first state to a second state.

26. The method of claim 25, wherein the slug is wetted by the liquid metal.

27. The method of claim 25, wherein the coupling between the slug and the second number of contacts is due to a plurality of surface tension forces caused by the liquid metal.

28. The method of claim 25, wherein the one or more piezoelectric elements have substantially equivalent actuation properties.

29. The method of claim 25, wherein one or more of the first number of contacts and one or more of the second number of contacts are the same.

30. The method of claim 25, wherein the liquid metal is separable into one or more volumes within the chamber.

31. The method of claim 25, wherein one or more of the one or more volumes of liquid metal are coupled to the one or more contacts.

32. The method of claim 25, wherein actuating one or more of the plurality of piezoelectric elements is operable to reduce a velocity of the slug.

33. The method of claim 25, wherein the one or more piezoelectric elements are located at an end of the chamber

34. The method of claim 25, wherein the plurality of piezoelectric elements are actuated in an adjacent manner.