MEMS device with a three-layer comb actuator structure and a two-layer hinge

Patent metadata

Field	Value
Publication number	US-11892619-B2
Application number	US-201916673180-A
Country	US
Kind code	B2
Filing date	Nov 4, 2019
Priority date	Sep 4, 2019
Publication date	Feb 6, 2024
Grant date	Feb 6, 2024

Abstract

A micro-sized optical device may comprise a mirror suspended on a set of hinges that are mounted to the substrate and that are configured to tilt the mirror about an axis, wherein a hinge of the set of hinges is a two-layer structure with a pivot point that aligns with a mass center of the mirror; and a three-layer comb actuator structure associated with the hinge of the set of hinges, wherein the three-layer comb actuator structure includes a rotor comb actuator, a first stator comb actuator, and a second stator comb actuator.

First claim

What is claimed is:

1. A micro-sized mechanical structure comprising:
a substrate;
a first layer adjacent to the substrate, a second layer adjacent to the first layer, and a third layer adjacent to the second layer;
a gimbal suspended on a set of first hinges that are mounted to the substrate and that are configured to tilt the gimbal about a first axis, wherein the gimbal forms part of the second layer;
a first comb actuator structure associated with a first hinge of the set of first hinges, wherein the first comb actuator structure includes a rotor comb actuator that forms part of the second layer and two stator comb actuators that respectively form part of the first layer and part of the third layer;
a mirror suspended on a set of second hinges that are mounted to the gimbal via a set of anchors and that are configured to tilt the mirror about a second axis; and
a second comb actuator structure associated with a second hinge of the set of second hinges, wherein the second comb actuator structure includes an additional rotor comb actuator that forms part of the third layer and two additional stator comb actuators that respectively form part of the first layer and part of the second layer.

2. The micro-sized mechanical structure of claim 1 , wherein the first comb actuator structure is a pure torque comb actuator structure.

3. The micro-sized mechanical structure of claim 1 , wherein the second comb actuator structure is a two-stage-stator comb actuator structure.

4. The micro-sized mechanical structure of claim 1 , wherein a first stator comb actuator of the two stator comb actuators is associated with a first electrode and a second stator comb actuator of the two stator comb actuators is associated with a second electrode.

5. The micro-sized mechanical structure of claim 1 , wherein the two additional stator comb actuators of the second comb actuator structure are bonded together via an oxide layer.

6. The micro-sized mechanical structure of claim 1 , wherein the first hinge of the set of first hinges is a two-layer structure with a pivot point that aligns with a mass center of the gimbal.

7. The micro-sized mechanical structure of claim 1 , wherein the second hinge of the set of second hinges is a two-layer structure with a pivot point that aligns with a mass center of the mirror.

8. The micro-sized mechanical structure of claim 1 , wherein the first comb actuator structure generates electrostatic torque to tilt the gimbal and the mirror about the first axis,
wherein the first comb actuator structure does not generate any linear electrostatic force.

9. The micro-sized mechanical structure of claim 1 , wherein the second comb actuator structure generates electrostatic torque to tilt the mirror about the second axis.

10. The micro-sized mechanical structure of claim 1 , wherein the substrate includes an opening to allow the gimbal and the mirror to tilt about the first axis or the mirror to tilt about the second axis.

11. The micro-sized mechanical structure of claim 1 , wherein the first layer, the second layer, and the third layer are electrically isolated from each other.

12. The micro-sized mechanical structure of claim 1 , wherein the rotor comb actuator of the first comb actuator structure is attached to the gimbal and the two stator comb actuators of the first comb actuator structure are secured to the substrate.

13. The micro-sized mechanical structure of claim 1 , wherein the additional rotor comb actuator of the second comb actuator structure is attached to the mirror and the two additional stator comb actuators of the second comb actuator structure are secured to the gimbal.

14. The micro-sized mechanical structure of claim 1 , wherein:
the mirror forms part of the third layer, and
the first axis is different than the second axis.

15. The micro-sized mechanical structure of claim 7 , wherein each layer of the two-layer structure respectively comprises a beam structure of one or more beams.

16. The micro-sized mechanical structure of claim 1 , wherein the two stator comb actuators of the first comb actuator structure are electrically isolated from each other.

17. The micro-sized mechanical structure of claim 1 , wherein the two additional stator comb actuators of the second comb actuator structure are electrically isolated from each other.

18. A micro-sized mechanical structure comprising:
a substrate;
a first layer adjacent to the substrate, a second layer adjacent to the first layer, and a third layer adjacent to the second layer;
a gimbal suspended on a set of first hinges that are mounted to the substrate and that are configured to tilt the gimbal about a first axis,
wherein the gimbal forms part of the second layer;

a first comb actuator structure associated with a first hinge of the set of first hinges,
wherein the first comb actuator structure includes a rotor comb actuator that forms part of the second layer and two stator comb actuators that respectively form part of the first layer and part of the third layer, and
wherein the first hinge of the set of first hinges is a two-layer structure comprising:
a double beam structure on a layer of the two-layer structure of the first hinge, and
a single beam structure on another layer of the two-layer structure of the first hinge;

a mirror suspended on a set of second hinges that are mounted to the gimbal via a set of anchors and that are configured to tilt the mirror about a second axis; and
a second comb actuator structure associated with a second hinge of the set of second hinges,
wherein the second comb actuator structure includes an additional rotor comb actuator that forms part of the third layer and two additional stator comb actuators that respectively form part of the first layer and part of the second layer.

19. The micro-sized mechanical structure of claim 18 , wherein the second comb actuator structure is a two-stage-stator comb actuator structure.

20. The micro-sized mechanical structure of claim 18 , wherein the mirror forms part of the third layer.

Assignees

• Lumentum Operations Llc

Inventors

• Jin Wenlin
• Bagnald Stephen
• Wills Gonzalo

Classifications

• G02B26/0841 Primary

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• B81B3/0021

  Transducers for transforming electrical into mechanical energy or vice versa (dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00) · CPC title

• H02N1/008

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• B81B2201/033

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