Resonator assembly comprising a silicon resonator and a quartz resonator

Patent metadata

Field	Value
Publication number	US-9250074-B1
Application number	US-201414249723-A
Country	US
Kind code	B1
Filing date	Apr 10, 2014
Priority date	Apr 12, 2013
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A resonator assembly comprising a semiconductor substrate, a resonator gyroscope, the resonator gyroscope including a first resonator formed in a layer of a first material, and an oscillator on the semiconductor substrate, the oscillator including a second resonator formed of a second material, wherein the second resonator is attached in a cavity; the cavity comprising a first recess in said layer of a first material and the edges of the first recess being attached to the substrate, or the cavity comprising a second recess in said substrate and the edges of the second recess being attached to said layer of a first material.

First claim

What is claimed is the following:

1. A resonator assembly comprising:
a semiconductor substrate;
a resonator gyroscope, the resonator gyroscope including a first resonator formed in a layer of a first material; and
an oscillator on the semiconductor substrate, the oscillator including a second resonator formed of a second material;
the second resonator being attached in a cavity; the cavity comprising a first recess in said layer of a first material and the edges of the first recess being attached to the substrate, or the cavity comprising a second recess in said substrate and the edges of the second recess being attached to said layer of a first material;
said first resonator being formed by etching said layer of a first material after said attaching the edges of the first recess to the substrate or said attaching the edges of the second recess to said layer of a first material; and
said cavity being located below a portion of said layer of a first material that is not etched when forming said first resonator.

2. The assembly of claim 1 , wherein the first material is silicon and the second material is quartz.

3. The resonator assembly of claim 2 , wherein the second resonator is a SC-cut shear-mode quartz resonator.

4. The resonator assembly of claim 2 , wherein the quartz resonator has electrodes comprising gold.

5. The resonator assembly of claim 1 , wherein the cavity comprises vent ports.

6. The resonator assembly of claim 5 , in which the two resonators are vacuum sealed in a common housing.

7. The resonator assembly of claim 6 in which heaters are placed on the outside surface of the common housing.

8. The assembly of claim 1 , wherein the cavity comprises said first recess in said layer of a first material and the edges of said first recess are attached to the substrate; said first resonator being formed by etching said layer of a first material after said attaching the edges of said first recess to the substrate.

9. The assembly of claim 1 , wherein the cavity comprises said second recess in said substrate and the edges of said second recess are attached to said layer of a first material; said first resonator being formed by etching said layer of a first material after said attaching the edges of said second recess to said layer of a first material.

10. The assembly of claim 1 , wherein the cavity comprises said first recess in said layer of a first material and said second recess in said substrate, the edges of said first recess and said second recess being attached together; said first resonator being formed by etching said layer of a first material after said attaching the edges of said first recess to the edges of said second recess.

11. The assembly of claim 1 , wherein the cavity comprises said first recess in said layer of a first material and said second recess in said substrate, the edges of said first recess and said second recess being attached together.

12. A resonator assembly comprising:
a semiconductor substrate;
a resonator gyroscope, the resonator gyroscope including a first resonator formed in a layer of a first material; and
an oscillator on the semiconductor substrate, the oscillator including a second resonator formed of a second material;
the second resonator being attached in a cavity, the cavity comprising a first recess in said layer of a first material and the edges of the first recess being attached to the substrate, or the cavity comprising a second recess in said substrate and the edges of the second recess being attached to said layer of a first material, wherein the first resonator comprises a central mounting stem, and wherein the cavity is located in said central mounting stem.

13. The resonator assembly of claim 12 , comprising a common heater centrally located beneath the first and second resonators.

14. The assembly of claim 12 , wherein the cavity comprises said first recess in said layer of a first material and the edges of said first recess are attached to the substrate.

15. The assembly of claim 12 , wherein the cavity comprises said second recess in said substrate and the edges of said second recess are attached to said layer of a first material.

16. A fabrication process for a resonator assembly, the process comprising:
providing a semiconductor substrate;
providing a layer of a first material;
etching at least part of a cavity in said layer of first material or in said substrate;
attaching an oscillator on the semiconductor substrate, the oscillator including a first resonator formed of a second material; and assembling said layer of first material on said substrate such that the first resonator is enclosed in said cavity;
the process further comprising:
forming a second resonator out of said layer of a first material by further etching said layer of a first material after said assembling, wherein said cavity is located below a portion of said layer of a first material that is not etched by said further etching.

17. The process of claim 16 , wherein said forming a second resonator comprises forming a second resonator having a central mounting stem; the cavity being located in said central mounting stem.

18. The process of claim 17 , comprising forming a common heater centrally located beneath the first and second resonators.

19. The process of claim 16 , wherein the first material is silicon and the second material is quartz.

20. The process of claim 19 , wherein the second resonator is a SC-cut shear-mode quartz resonator.

21. The process of claim 19 , wherein, wherein the quartz resonator has electrodes comprising gold.

22. The process of claim 16 , wherein said assembling said layer of first material on said substrate such that the second resonator is enclosed in said cavity comprises providing the cavity with vent ports.

23. The process of claim 22 , further comprising vacuum sealing the two resonators in a common housing.

24. The process of claim 23 , further comprising arranging heaters on the outside surface of the common housing.

25. The process of claim 16 , comprising etching said cavity in said layer of first material.

26. The process of claim 16 , comprising etching said cavity in said substrate.

27. The process of claim 16 , comprising etching a first part of said cavity in said layer of first material and a second part of said cavity in said substrate.

Assignees

• Hrl Lab Llc

Inventors

• Kubena Randall L
• Chang David T

Classifications

• H01L41/25

  Electricity · mapped topic

• H03H3/02

  for the manufacture of piezoelectric or electrostrictive resonators or networks (H03H3/08 takes precedence) · CPC title

• B81C1/00261

  Processes for packaging MEMS devices (MEMS packages B81B7/0032, packaging of smart-MEMS B81C1/0023) · CPC title

• G01P15/14

  by making use of gyroscopes (gyroscopes per se G01C19/00) · CPC title

• G01C19/56 Primary

  Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces · CPC title