Symmetric dual piezoelectric stack microelectromechanical piezoelectric devices

• US 9,502,635 B2
• Filed: 03/07/2014
• Issued: 11/22/2016
• Est. Priority Date: 03/07/2014
• Status: Expired due to Fees

• Current Assignee: Wireless Sensor Solutions, LLC
• Original Assignee: MicroGen Systems, Inc.
• Inventors: Andosca, Robert G., Vaeth, Kathleen M., Lacroix, Didier
• Primary Examiner(s): Dougherty, Thomas
• Application Number:
  US14/201,293
• Publication Number:
  US 20150256144A1
• Time in Patent Office: 991 Days
• Field of Search: 310311-371
• US Class Current: 1/1
• 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 9/2457 Clamped-free beam resonators
• CPC Class Codes: H10N 30/01 Manufacture or treatment
• CPC Class Codes: H10N 30/10516 Intermediate layers, e.g. barrier, adhesion or growth control buffer layers
• CPC Class Codes: H10N 30/20 with electrical input and mechanical output, e.g. functioning as actuators or vibrators
• CPC Class Codes: H10N 30/2041 Beam type
• CPC Class Codes: H10N 30/304 Beam type
• CPC Class Codes: H10N 30/50 having a stacked or multilayer structure
• CPC Class Codes: H10N 30/708 Intermediate layers, e.g. barrier, adhesion or growth control buffer layers

Abstract

The present invention relates to a device comprising an elongate resonator beam extending between first and second ends. A base is connected to the resonator beam at the first end with the second end extending from the base as a structural layer. The elongate resonator beam comprises either: (1) a first oxide layer on a first piezoelectric stack layer over a structural layer on a second oxide layer over a second piezoelectric stack layer on a third oxide layer or (2) a first oxide layer on a first piezoelectric stack layer over a second oxide layer on a structural layer over a third oxide layer on a second piezoelectric stack over a fourth oxide layer. Also disclosed is a system comprising an apparatus and the device, as well as methods of making and using the device.

Claims

1. A device comprising

an elongate resonator beam extending between first and second ends and

a base connected to said elongate resonator beam at the first end with the second end extending from said base as a structural layer, wherein said elongate resonator beam comprises either:

(1) a first oxide layer on a first piezoelectric stack layer over a structural layer on a second oxide layer over a second piezoelectric stack layer on a third oxide layer or (2) a first oxide layer on a first piezoelectric stack layer over a second oxide layer on a structural layer over a third oxide layer on a second piezoelectric stack over a fourth oxide layer.

2. The device of claim 1, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a structural layer on a second oxide layer over a second piezoelectric stack layer on a third oxide layer.

3. The device of claim 1, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a second oxide layer on a structural layer over a third oxide layer on a second piezoelectric stack over a fourth oxide layer.

4. The device of claim 1, wherein the second piezoelectric stack layer comprises a conductive material layer over a piezoelectric material layer over a conductive material layer.

5. The device of claim 1, wherein the first piezoelectric stack layer comprises a conductive material layer over a piezoelectric material layer and the structural layer is useful as an electrode.

6. The device of claim 1, wherein the first piezoelectric stack layer comprises a conductive material layer over a piezoelectric material layer on a conductive material layer.

7. The device of claim 1 further comprising:

one or more electrodes in electrical contact with the first and/or second piezoelectric stack layer.

8. The device of claim 7 further comprising:

a display in electrical connection with the one or more electrodes to obtain a reading from the first and/or second piezoelectric stack layer.

9. The device of claim 1, wherein the first and/or second piezoelectric stack layer comprises a conductive material layer wherein the conductive material layer is selected from the group consisting of molybdenum, platinum, and polysilicon.

10. The device of claim 1, wherein the first and/or second piezoelectric stack layer comprises a layer of piezoelectric material, wherein the piezoelectric material is selected from the group consisting of aluminum nitride, zinc oxide, polyvinylidene fluoride, and lead zirconate titanate compounds.

11. The device of claim 1, wherein the structural layer is made from a material selected from the group consisting of electroplated copper or nickel, and polysilicon.

12. The device of claim 1, wherein said base extends without interruption from said first end to said second end.

13. The device of claim 1, wherein said base comprises a first base portion connected to said first end and a second base portion connected to said second end, wherein said first base portion is not in contact with said second base portion.

14. The device of claim 1, wherein said base extends from said first end to said second end but is spaced from said elongate resonator beam at said second end.

15. The device of claim 1, wherein the device comprises a sensor.

16. The device of claim 15, wherein the sensor is selected from the group consisting of an accelerometer, a gyroscope, a pressure sensor, a strain sensor, a flow sensor, or a microphone.

17. The device of claim 1, wherein the device comprises an actuator.

18. The device of claim 17, wherein the actuator is selected from the group consisting of a valve, a pump, or a speaker.

19. The device of claim 1, wherein the device comprises one or more sensors and one or more actuators integrated on a chip.

20. A system comprising:

an apparatus and

the device according to claim 1 electrically coupled to the apparatus.

21. The system according to claim 20, wherein said apparatus is selected from the group consisting of a laptop computer, a tablet computer, a cell phone, a smart phone, an e-reader, an MP3 player, a telephony headset, headphones, a router, a gaming device, a gaming controller, a mobile internet adapter, a camera, wireless sensors, wireless sensor motes, tire pressure sensor monitors, powering simple displays on power tools, devices for raising livestock, medical devices, human body monitoring devices, and toys.

22. The system of claim 20, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a structural layer on a second oxide layer over a second piezoelectric stack layer on a third oxide layer.

23. The system of claim 20, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a second oxide layer on a structural layer over a third oxide layer on a second piezoelectric stack over a fourth oxide layer.

24. The system of claim 20 further comprising:

one or more electrodes in electrical contact with the first and/or second piezoelectric stack layer.

25. The system of claim 24 further comprising:

circuitry in electrical connection with the one or more electrodes to output and measure electrical energy from the first and/or second piezoelectric stack layer.

26. A method of measuring an environmental condition, said method comprising:

providing the system according to claim 20;

subjecting the system to one or more environmental conditions that generate movement or vibrations to generate electrical energy from the first and/or second piezoelectric stack layer; and

measuring the environmental condition based on said electrical energy from the first and/or second piezoelectric stack layer.

27. The method of claim 26, wherein said apparatus is selected from the group consisting of a laptop computer, a tablet computer, a cell phone, a smart phone, an e-reader, an MP3 player, a telephony headset, headphones, a router, a gaming device, a gaming controller, a mobile internet adapter, a camera, wireless sensors, wireless sensor motes, tire pressure sensor monitors, powering simple displays on power tools, devices for raising livestock, medical devices, human body monitoring devices, and toys.

28. The method of claim 26, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a structural layer on a second oxide layer over a second piezoelectric stack layer on a third oxide layer.

29. The method of claim 26, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a second oxide layer on a structural layer over a third oxide layer on a second piezoelectric stack over a fourth oxide layer.

30. The method of claim 26, wherein said system further comprises:

one or more electrodes in electrical contact with the first and/or second piezoelectric stack layer.

31. The method of claim 30, wherein said system further comprises:

circuitry in electrical connection with the one or more electrodes to output electrical energy from the first and/or second piezoelectric stack layer.

32. The method of claim 26, wherein the environmental condition comprises one or more of pressure, vibration, flow rate, strain, physical motion relative to a force, impulse motion, or sound.

33. A method for providing a mechanical actuation force, the method comprising:

providing the system according to claim 1;

providing a voltage source in electrical connection with the device;

applying a voltage to the device from the voltage source, wherein the applied voltage initiates motion of the elongate resonator beam; and

providing a mechanical actuation force based on the motion of the elongate resonator beam.

34. The method of claim 33 wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a structural layer on a second oxide layer over a second piezoelectric stack layer on a third oxide layer.

35. The method of claim 33, wherein said elongate resonator beam comprises a first oxide layer on a first piezoelectric stack layer over a second oxide layer on a structural layer over a third oxide layer on a second piezoelectric stack over a fourth oxide layer.

36. The method of claim 33, wherein said system further comprises:

one or more electrodes in electrical contact with the first and/or second piezoelectric stack layer.

37. The method of claim 36, wherein said system further comprises:

circuitry in electrical connection with the voltage source and the one or more electrodes to deliver the voltage to the first and/or second piezoelectric stack layer.