Micromachined devices and connections over a substrate

• US 6,505,512 B2
• Filed: 12/17/2001
• Issued: 01/14/2003
• Est. Priority Date: 09/02/1997
• Status: Expired due to Term

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Geen, John A., Carow, Donald W.
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US10/022,690
• Publication Number:
  US 20020046605A1
• Time in Patent Office: 393 Days
• Field of Search: 735/041.2, 735/041.3, 735/041.4, 735/041.5, 735/041.6, 735/040.4, 735/143.2, 735/143.8, 361/283.1, 361/283.3
• US Class Current: 73/504.14
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis

Abstract

A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Claims

1. A micromachined device comprising:

a substrate;

a first body suspended in a plane over the substrate and movable in the plane along a first direction;

an

anchored member, elongated next to a side of the first body along a second direction transverse to the first direction, the anchored member having first and second opposite ends in the lengthwise direction and having flexures extending from each end of the anchored member to the first body, the flexures allowing the first body to move in the first direction more easily than in the second direction, the member being anchored with at least one anchor positioned centrally along the anchored member between the first and second opposite ends, wherein the anchored member includes a first plate anchored to the substrate, a second plate from which flexures extend to the first body, and flexures extending between the first plate and the second plate to allow pivoting about a pivot point between the first and second plates.

2. The device of claim 1, wherein the second plate includes first and second substantially identical and symmetric portions coupled together through a connecting flexure between the portions to allow pivoting between the first and second portions at the connecting flexure.

3. The device of claim 1, further comprising a package, wherein the device is packaged in the package under ambient conditions.

4. A micromachined device comprising:

a substrate;

a first body suspended in a plane over the substrate and movable in the plane along a first direction;

an anchored member, elongated next to a side of the first body along a second direction transverse to the first direction, the anchored member having first and second opposite ends in the lengthwise direction and having flexures extending from each end of the anchored member to the first body, the flexures allowing the first body to move in the first direction more easily than in the second direction, the member being anchored with at least one anchor positioned centrally along the anchored member between the first and second opposite ends; and

a second body suspended over the substrate and interconnected with the first body to allow the second body to move along the second direction relative to the first body.

5. The device of claim 4, wherein the second body surrounds the first body and the anchored member is in a region between the first and second bodies.

6. The device of claim 4, wherein the first body surrounds the second body and the anchoring member is not surrounded by the first body.

7. The device of claim 4, further comprising a package, wherein the device is packaged in the package under ambient conditions.

8. A micromachined device comprising:

a substrate;

a first body suspended in a plane over and parallel to the substrate and movable relative to the substrate in the plane along a first direction;

a second body anchored to the substrate and coupled to the first body to allow movement in the first direction and to resist movement in a second direction transverse to the first direction, the second body having first and second plates with connecting sets of perpendicular flexures between them.

9. The device of claim 8, wherein the second body is elongated and anchored with at least one anchor positioned centrally between first and second opposite ends.

10. The device of claim 9, wherein the anchor extends to the substrate from the first plate, and the second plate is coupled to the first body with coupling flexures.

11. The device of claim 10, wherein the flexures are short relative to a length of the second body.

12. The device of claim 10, wherein the second plate includes first and second substantially identical and symmetric portions coupled together through a connecting flexure between the portions to allow pivoting between the first and second portions at the connecting flexure.

13. The device of claim 12, wherein the coupling flexures and connecting flexure are co-linear.

14. The device of claim 8, wherein the second plate includes first and second substantially identical and symmetric portions coupled together through a connecting flexure between the portions to allow pivoting between the first and second portions at the connecting flexure.

15. The device of claim 8, further comprising a package, wherein the device is packaged in the package under ambient conditions.

16. A micromachined device comprising:

a substrate,

a first body suspended in a plane over the substrate and movable in the plane along a first direction;

an anchored member, elongated next to a side of the first body along a second direction transverse to the first direction, the anchored member having first and second opposite ends in the lengthwise direction and having flexures extending from each end of the anchored member to the first body, the flexures allowing the first body to move in the first direction more easily than in the second direction, the anchored member having first and second plates connected together, wherein the second plate includes first and second substantially identical and symmetric portions coupled together through a connecting flexure between the portions to allow pivoting between the first and second portions at the connecting flexure.

17. The device of claim 16, wherein the first plate is directly anchored and the second plate Is not directly anchored to the substrate, the second plate being connected to the first body.

18. The device of claim 17, wherein the first plate is anchored with one or more anchors centrally located at the center in the lengthwise direction.

19. The device of claim 16, further comprising a package, wherein the device is packaged in the package under ambient conditions.