Miniaturized switch device

• US 20060197635A1
• Filed: 03/03/2006
• Published: 09/07/2006
• Est. Priority Date: 03/04/2005
• Status: Active Grant

• Current Assignee: HT Microanalytical, Inc. (Rosenberger Technology (Kunshan) Co., Ltd.)
• Original Assignee: HT Microanalytical, Inc. (Rosenberger Technology (Kunshan) Co., Ltd.)
• Inventors: Christenson, Todd
• Granted Patent: US 7,999,642 B2
• Time in Patent Office: Days
• US Class Current: 335/78
• CPC Class Codes: H01H 2001/0078 with parallel movement of the movable contact relative to the substrate
• CPC Class Codes: H01H 2050/007 Relays of the polarised type, e.g. the MEMS relay beam having a preferential magnetisation direction
• CPC Class Codes: H01H 50/005 using micromechanics

Abstract

The present invention provides a switch suitable for efficient microfabrication. The switch elements are disposed in several layers. Various embodiments provide various switching capabilities and operational characteristics. The switches can be protected by suitable packaging, and can be efficiently fabricated in groups or arrays.

Claims

1. A microfabricated switch, comprising:

a. A base layer;

b. A moveable member layer substantially parallel to the base layer, having disposed therein a moveable member that is moveable between first and second positions, and where the moveable member is constrained to move substantially parallel to the base layer;

c. First and second terminals, mounted relative to the moveable member such that when the moveable member is in the first position electrical current can flow between the first and second terminals.

2. A switch as in claim 1, further comprising a third terminal, mounted relative to the moveable member such that when the moveable member is in the second position electrical current can flow between the first and third terminals.

3. A switch as in claim 1, further comprising third and fourth terminal, mounted relative to the moveable member such that when the moveable member is in the second position electrical current can flow between the third and fourth terminals.

4. A switch as in claim 1, further comprising first and second contacts, where the first contact is in mechanical communication with the moveable member and in electrical communication with the first terminal, and wherein the second contact is in electrical communication with the second terminal, and wherein the first and second contacts mount relative to the moveable member such that the first and second contacts are in electrical communication when the moveable member is in the first position but not when the moveable member is in the second position.

5. A switch as in claim 4, wherein the first contact moves substantially parallel to the base layer responsive to motion of the moveable member.

6. A switch as in claim 5, wherein the first contact moves substantially within one of the base layer, the moveable member layer, or a third layer.

7. A switch as in claim 1, wherein the moveable member is mechanically bistable with respect to the first and second positions.

8. A switch as in claim 4, wherein the first and second contacts are not disposed in the moveable member layer.

9. A switch as in claim 1, wherein the moveable member moves responsive to external force applied thereto.

10. A switch as in claim 1, further comprising an electromagnetic actuator, mounted relative to the moveable member such that the moveable member moves responsive to force applied from the electromagnetic actuator.

11. A switch as in claim 1, further comprising at least one of (i) a thermal actuator, (ii) a piezoelectric actuator, or (iii) a pneumatic actuator, mounted relative to the moveable member such that the moveable member moves responsive to a force applied from the actuator.

12. A switch as in claim 1, further comprising an electromagnetic actuator comprising a coil having north and south poles mounted such that the north and south poles are both substantially disposed in a single layer, and mounted relative to the moveable member such that the moveable member moves responsive to force applied from the electromagnetic actuator.

13. A switch as in claim 10, further comprising an insulating material disposed between the electromagnetic actuator and at least a portion of the current path from the first terminal to the second terminal such that the insulating material establishes electromagnetic separation between the electromagnetic actuator and the portion of the current path.

14. A switch assembly, comprising a first switch as in claim 1, and a second switch as in claim 1, wherein the base layers of the first and second switches are substantially coplanar.

15. A switch assembly, comprising a first switch as in claim 1, and a second switch as in claim 1, wherein the base layers of the first and second switches are substantially parallel to each other but not coplanar with each other.

16. A switch assembly, comprising a first switch as in claim 1, and a second switch as in claim 1, wherein at least one terminal of the first switch is in electrical communication with at least one terminal of the second switch.

17. A switch as in claim 1, further comprising an electromagnetic actuator having a core with winding, wherein the north and south poles of the electromagnetic actuator are disposed substantially in the moveable member layer, and wherein the winding is not disposed substantially in the moveable member layer.

18. A switch as in claim 1, further comprising an electromagnetic actuator having a core with winding, wherein the north and south poles of the electromagnetic actuator are disposed substantially in the moveable member layer, and wherein the winding is disposed substantially in the moveable member layer.

19. A switch as in claim 1, further comprising an electromagnetic actuator, comprising magnet wire wound around a mandrel.

20. A switch as in claim 19, wherein the mandrel interfaces with north and south poles of the electromagnetic actuator via a castellated mechanical interface.

21. A switch as in claim 1, further comprising a high aspect ratio comb drive.

22. A switch as in claim 1, further comprising an electrostatic parallel plate actuator.

23. A switch as in claim 1, further comprising a mechanical member capable of first and second configurations, mounted relative to the moveable member such that when in the first configuration the mechanical member urges the moveable member to the first position, and when in the second position the mechanical member urges the moveable member to the second position.

24. A switch as in claim 23, wherein the mechanical member comprises a flexure.

25. A switch as in claim 24, wherein the first and second configurations comprise first and second buckled states of the flexure, and wherein the flexure is mounted such that once it enters a buckled state it remains in that buckled state until a force exceeding a threshold force is applied.

26. A switch as in claim 1, further comprising a permanent magnet mounted relative to the moveable member such that the permanent magnet exerts a latching force on the moveable member when the moveable member is in a latched position, wherein the latched position is one of the first or second positions, and wherein the moveable member remains in the latched position until a force exceeding the latching force is applied.

27. A switch as in claim 1, further comprising

a. a first permanent magnet mounted relative to the moveable member such that the first permanent magnet exerts a first latching force on the moveable member when the moveable member is in the first position, and wherein the moveable member remains in the first position until a force exceeding the first latching force is applied;

and

b. further comprising a second permanent magnet mounted relative to the moveable member such that the second permanent magnet exerts a second latching force on the moveable member when the moveable member is in the second position, and

wherein the moveable member remains in the second position until a force exceeding the second latching force is applied.

28. A switch as in claim 23, wherein the mechanical member comprises a beam with

a. a first portion thereof mounted with the moveable member and

b. a second portion thereof mounted fixedly with respect to the base layer.

29. A switch as in claim 28, wherein the first portion comprises a first end of the beam, and wherein the second portion comprises a second end of the beam.

30. A switch as in claim 23, wherein the mechanical member comprises a plurality of beams, each with

a. a first portion thereof mounted with the moveable member and

b. a second portion thereof mounted fixedly with respect to the base layer.

31. A switch as in claim 23, wherein the mechanical member comprises a beam with

a. first and second portions thereof mounted fixedly with respect to the base layer and

b. with a third portion, intermediate between the first and second portions, mounted with the moveable member.

32. A switch as in claim 23, wherein the mechanical member is disposed substantially in the moveable member layer.

33. A switch as in claim 23, wherein the mechanical member is disposed substantially not in the moveable member layer.

34. A switch as in claim 23, wherein the mechanical member comprises a first member disposed substantially in the moveable member layer, and a second member disposed substantially not in the moveable member layer.

35. A switch as in claim 23, wherein the mechanical member comprises a first member disposed substantially in a first layer that is not the moveable member layer, and a second member disposed substantially a second layer that is not the moveable member layer and is not the first layer.

36. A switch as in claim 8, further comprising an insulator between the moveable member layer and the contacts.

37. A switch as in claim 26, wherein the insulator is an insulating layer disposed between the moveable member layer and the contacts, or an insulating coating disposed between the moveable member layer and the contacts.

38. A switch as in claim 4, wherein the contacts are disposed substantially in the moveable member layer, and further comprising an insulating portion of the moveable member layer between the moveable member and each of the contacts.

39. A switch as in claim 1, further comprising a housing that substantially prevents external contaminants from reaching the moveable member, and that allows electrical communication with the terminals.

40. A switch as in claim 39, wherein the moveable member layer mounts relative to the base layer on a first side of the base layer, and wherein the terminals are externally accessible on a second side of the base layer, and wherein the housing is substantially disposed on the first side of the base layer.

41. A switch as in claim 39, wherein the terminals are externally accessible in a first portion of the base layer, and wherein the housing mounts with a second portion of the base layer.

42. A switch as in claim 14, further comprising a housing hat substantially prevents external contaminants from reaching the moveable members and the two switches, and that allows electrical communication with at least some of the terminals thereof.

43. A microfabricated switch, comprising:

a. A base layer;

b. An electrical circuit layer, having first and second electrical conductors disposed thereon such that there is a gap between the first and second conductors, and having a contactor disposed in the gap and moveable to a first configuration where the contactor is in electrical communication with both the first and second conductors, and to a second configuration where the contactor is not in electrical communication with both the first and second conductors;

c. An actuation layer, comprising a moveable member and an actuator disposed such that energization of the actuator cause the moveable member to move between first and second positions;

d. An insulating layer, disposed between the electrical circuit layer and the actuation layer, and having a mechanical linkage that couples movement of the moveable member to movement of the contactor.