Quartz-based disk resonator gyro with ultra-thin conductive outer electrodes and method of making same

• US 8,766,745 B1
• Filed: 06/22/2009
• Issued: 07/01/2014
• Est. Priority Date: 07/25/2007
• Status: Active Grant

• Current Assignee: HRL Laboratories LLC (The Boeing Co.), The Boeing Co.
• Original Assignee: HRL Laboratories LLC (The Boeing Co.), The Boeing Co.
• Inventors: Kubena, Randall L., Chang, David T., Larson, Robert L.
• Primary Examiner(s): Takaoka, Dean O
• Assistant Examiner(s): Wong, Alan
• Application Number:
  US12/488,784
• Time in Patent Office: 1,835 Days
• Field of Search: 333/186, 333/197, 333/199, 735/033, 735/040.4, 735/041.2
• US Class Current: 333/186
• CPC Class Codes: G01C 19/5684 the devices involving a micromechanical structure
• CPC Class Codes: G01P 1/00 Details of instruments
• CPC Class Codes: H03H 2009/02283 Vibrating means
• CPC Class Codes: H03H 2009/02496 Horizontal, i.e. parallel to the substrate plane
• CPC Class Codes: H03H 3/0072 of microelectro-mechanical resonators or networks micromembranes or microbeams B81B2203/01; manufacture of microstructural devices in general B81C
• CPC Class Codes: H03H 9/02244 of microelectro-mechanical resonators
• CPC Class Codes: H03H 9/0552 the device and the other elements being mounted on opposite sides of a common substrate
• CPC Class Codes: H03H 9/1057 for microelectro-mechanical devices
• CPC Class Codes: H03H 9/2436 Disk resonators

Abstract

A disk resonator gyroscope includes a quartz base, a quartz resonator disk having a central pillar connected to the base, the quartz resonator disk having a surface facing the base and having plurality of circumferential slots in the surface of the quartz resonator disk around the central pillar, and an electrode comprised of quartz and connected to the base outside of an outer edge of the resonator disk.

Claims

1. A disk resonator gyroscope comprising:

a quartz base;

a quartz resonator disk having a central pillar connected to the base, the quartz resonator disk having a surface facing the base and having plurality of circumferential slots in the surface of the quartz resonator disk around the central pillar; and

an electrode comprised of quartz and connected to the base, the electrode outside of an outer edge of the resonator disk and not connected to the outer edge of the resonator disk;

a conductive film on the surface of the resonator disk, the outer edge of the resonator disk, the central pillar, and an inner wall of the electrode;

wherein the inner wall of the electrode faces the outer edge of the resonator disk.

2. The disk resonator gyroscope of claim 1 wherein:

the base comprises fused quartz;

the resonator disk comprises fused quartz; and

the electrode comprises fused quartz.

3. The disk resonator gyroscope of claim 1 wherein:

a gap between the electrode and the outer edge of the resonator disk is about 50 microns.

4. The disk resonator gyroscope of claim 1 wherein the electrode further comprises a drive electrode comprised of quartz and connected to the base outside of the outer edge of the resonator disk.

5. The disk resonator gyroscope of claim 1 wherein the electrode further comprises a sense electrode comprised of quartz and connected to the base outside of the outer edge of the resonator disk.

6. The disk resonator gyroscope of claim 1 wherein:

the base has about a 500 μ

m thickness; and

the resonator disk has about a 125 μ

m thickness.

7. The disk resonator gyroscope of claim 1 wherein the base further comprises:

a first raised area and metal deposited on the first raised area for connecting to the central pillar; and

a second raised area and metal deposited on the second raised area for electrical connection and bonding to the electrode;

wherein the first raised area has a height of about 3-4 μ

m; and

wherein the second raised area has a height of about 3-4 μ

m.

8. The disk resonator gyroscope of claim 1 further comprising:

a conductive film on a surface of the electrode;

wherein the surface of the electrode faces the base.

9. The disk resonator gyroscope of claim 1 wherein the conductive film is an Atomic Layer Deposition metal.

10. The disk resonator gyroscope of claim 1 wherein the conductive film is less than 100 nanometers thick.

11. The disk resonator gyroscope of claim 1 wherein the conductive film comprises one of Pt, Ru, Rh, Pd, Re, or Ir.

12. The disk resonator gyroscope of claim 8 further comprising an adhesion ALD layer between the conductive film and the surface of the resonator disk, the outer edge of the resonator disk, the central pillar, and the surface and the inner wall of the electrode.

13. The disk resonator gyroscope of claim 12 wherein the adhesion ALD layer comprises Al₂O₃.

14. The disk resonator gyroscope of claim 8 further comprising:

a conductive coating over the conductive film on the central pillar and on the surface of the electrode for interconnect and bonding to the base.

15. The disk resonator gyroscope of claim 14 wherein the conductive coating is gold and is about 0.5 μ

m thick.

16. A disk resonator gyroscope comprising:

a quartz base;

a quartz resonator disk having a central pillar connected to the base, the quartz resonator disk having a surface facing the base and having plurality of circumferential slots in the surface of the quartz resonator disk around the central pillar;

an electrode comprised of quartz and connected to the base, the electrode outside of an outer edge of the resonator disk and not connected to the outer edge of the resonator disk;

a conductive film on the surface of the resonator disk, the outer edge of the resonator disk, the central pillar, and a surface and an inner wall of the electrode;

wherein the inner wall of the electrode faces the outer edge of the resonator disk;

wherein the surface of the electrode faces the base; and

wherein a gap between the electrode and the outer edge of the resonator disk is less than or equal to 50 microns.

17. The disk resonator gyroscope of claim 16 wherein:

the base comprises fused quartz;

the resonator disk comprises fused quartz; and

the electrode comprises fused quartz.

18. The disk resonator gyroscope of claim 16 wherein the electrode further comprises a drive electrode comprised of quartz and connected to the base outside of the outer edge of the resonator disk.

19. The disk resonator gyroscope of claim 16 wherein the electrode further comprises a sense electrode comprised of quartz and connected to the base outside of the outer edge of the resonator disk.

20. The disk resonator gyroscope of claim 16 wherein:

the base has about a 500 μ

m thickness; and

the resonator disk has about a 125 μ

m thickness.

21. The disk resonator gyroscope of claim 16 wherein the base further comprises:

a first raised area and metal deposited on the first raised area for connecting to the central pillar; and

a second raised area and metal deposited on the second raised area for electrical connection and bonding to the electrode;

wherein the first raised area has a height of about 3-4 μ

m; and

wherein the second raised area has a height of about 3-4 μ

m.

22. The disk resonator gyroscope of claim 16 wherein the conductive film is an Atomic Layer Deposition metal.

23. The disk resonator gyroscope of claim 16 wherein the conductive film is less than 100 nanometers thick.

24. The disk resonator gyroscope of claim 16 wherein the conductive film comprises one of Pt, Ru, Rh, Pd, Re, or Ir.

25. The disk resonator gyroscope of claim 16 further comprising an adhesion ALD layer between the conductive film and the surface of the resonator disk, the outer edge of the resonator disk, the central pillar, and the surface and the inner wall of the electrode.

26. The disk resonator gyroscope of claim 25 wherein the adhesion ALD layer comprises Al₂O₃.

27. The disk resonator gyroscope of claim 16 further comprising:

a conductive coating over the conductive film on the central pillar and on the surface of the electrode for interconnect and bonding to the base.

28. The disk resonator gyroscope of claim 27 wherein the conductive coating is gold and is about 0.5 μ

m thick.