MEMS device and method for operating a MEMS device

Patent metadata

Field	Value
Publication number	US-12470874-B2
Application number	US-202318316589-A
Country	US
Kind code	B2
Filing date	May 12, 2023
Priority date	Jun 2, 2022
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

A MEMS device and a method for operating a MEMS device are provided. The MEMS device comprises a piezoelectric transducer element having at least a first piezoelectric transducer region and a deflectable structure, wherein the deflectable structure comprises the piezoelectric transducer element. The MEMS device further comprises a control circuitry configured to readout at least a first sensor signal from the first region of the piezoelectric transducer element based on a deflection of the deflectable structure. The control circuitry is further configured to determine a control signal from the readout first sensor signal, wherein the control signal has a counteracting effect to the deflection of the deflectable structure when provided to the piezoelectric transducer element. The control circuitry is configured to provide the control signal to the piezoelectric transducer element for counteracting the deflection of the deflectable structure.

First claim

What is claimed is:

1 . A micro-electro-mechanical system (MEMS) device comprising:
a piezoelectric transducer element having a first transducer region and a second transducer region; a deflectable structure comprising the piezoelectric transducer element; and a control circuit configured to:
readout a first sensor signal from the first transducer region of the piezoelectric transducer element based on a deflection of the deflectable structure;
determine a control signal from the readout first sensor signal, wherein the control signal has a counteracting effect on the deflection of the deflectable structure when provided to the piezoelectric transducer element;
provide the control signal to the first transducer region of the piezoelectric transducer element for counteracting the deflection of the deflectable structure; and
toggle between reading out the first sensor signal from the first transducer region of the piezoelectric transducer element and providing the control signal to the first transducer region of the piezoelectric transducer element,
wherein the first transducer region comprises a piezoelectric material disposed between a first readout terminal and a counter electrode, and wherein the second transducer region comprises the piezoelectric material disposed between a second readout terminal and the counter electrode.

2 . The MEMS device of claim 1 , wherein the control circuit is configured to perform toggling in a MHz domain.

3 . A micro-electro-mechanical system (MEMS) device comprising:
a piezoelectric transducer element having a first transducer region and a second transducer region; a deflectable structure comprising the piezoelectric transducer element; and a control circuit configured to:
readout a first sensor signal from the first transducer region of the piezoelectric transducer element based on a deflection of the deflectable structure;
determine a control signal from the readout first sensor signal, wherein the control signal has a counteracting effect on the deflection of the deflectable structure when provided to the piezoelectric transducer element; and
provide the control signal to the piezoelectric transducer element for counteracting the deflection of the deflectable structure,
wherein the first transducer region comprises a piezoelectric material disposed between a first readout terminal and a counter electrode, and wherein the second transducer region comprises the piezoelectric material disposed between a second readout terminal and the counter electrode.

4 . The MEMS device of claim 3 , wherein the control circuit comprises a feedback control loop configured to derive the control signal from the readout first sensor signal and to apply the control signal to the piezoelectric transducer element.

5 . The MEMS device of claim 3 , wherein the control circuit comprises a feedback control loop configured to provide the control signal as a time dependent signal to the piezoelectric transducer element to actively dampen the deflection of the deflectable structure.

6 . The MEMS device of claim 4 , wherein the control circuit comprises an analog front end (AFE) circuit configured to read out the first sensor signal in an analog manner and to provide a processed analog signal to the feedback control loop for determining the control signal.

7 . The MEMS device of claim 3 , wherein:
the control signal comprises information indicative of the deflection of the deflectable structure; and the control circuit is further configured to:
derive an output signal of the MEMS device from the control signal, and
provide the output signal having information on an amplitude and frequency of the deflection of the deflectable structure.

8 . The MEMS device of claim 3 , wherein the control circuit is further configured to:
provide, to the piezoelectric transducer element, a test signal configured to cause a deflection of the deflectable structure; readout a test response signal from the first transducer region of the piezoelectric transducer element based on the deflection of the deflectable structure caused by the test signal; and adapt, based on the test response signal, parameters that form a basis for determining the control signal.

9 . The MEMS device of claim 3 , wherein:
the piezoelectric transducer element comprises a second transducer region; and the control circuit is configured to provide the control signal to the second transducer region of the piezoelectric transducer element for counteracting the deflection of the deflectable structure.

10 . The MEMS device of claim 9 , wherein the control circuit is configured to apply a reference signal to the counter electrode.

11 . The MEMS device of claim 3 , wherein the control circuit is configured to apply a reference signal to the counter electrode.

12 . A method for operating a MEMS device comprising a piezoelectric transducer element having a first transducer region and a second transducer region, a deflectable structure comprising the piezoelectric transducer element, and a control circuit, the method comprising:
reading out, by the control circuit, a first sensor signal from the first transducer region of the piezoelectric transducer element based on a deflection of the deflectable structure; determining, by the control circuit, a control signal from at least the readout first sensor signal, wherein the control signal has a counteracting effect on the deflection of the deflectable structure when provided to the piezoelectric transducer element; providing, by the control circuit, the control signal to the first transducer region of the piezoelectric transducer element for counteracting the deflection of the deflectable structure; and wherein the first transducer region comprises a piezoelectric material disposed between a first readout terminal and a counter electrode, and wherein the second transducer region comprises the piezoelectric material disposed between a second readout terminal and the counter electrode.

13 . The method of claim 12 , further comprising:
deriving, by a feedback control loop, the control signal from at least the readout first sensor signal; and applying, by the feedback control loop, the control signal to the piezoelectric transducer element.

14 . The method of claim 12 , further comprising:
actively dampening the deflection of the deflectable structure by providing, via a feedback control loop, the control signal as a time dependent signal to the piezoelectric transducer element.

15 . The method of claim 14 , further comprising:
reading out, by an analog front end (AFE) the first sensor signal in an analog manner; and providing a processed analog signal to the feedback control loop for determining the control signal.

16 . The method of claim 12 , wherein:
the control signal comprises information indicative of the deflection of the deflectable structure; and the method further comprises:
deriving, by the control circuit, an output signal of the MEMS device from the control signal, and
providing, by the control circuit, the output signal having information on an amplitude and frequency of the deflection of the deflectable structure.

17 . The method of claim 12 ,
further comprising providing, by the control circuit, the control signal to the second transducer region of the piezoelectric transducer element for counteracting the deflection of the deflectable structure.

18 . A micro-electro-mechanical system (MEMS) device comprising:
a piezoelectric transducer element having

Assignees

• Infineon Technologies Ag

Inventors

• Bretthauer Christian
• Bogner Andreas
• Bosetti Gabriele
• De Milleri Niccoló

Classifications

• H04R2201/003

  Mems transducers or their use · CPC title

• B81B2201/0257

  Microphones or microspeakers · CPC title

• B81B7/02

  containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] (B81B7/04 takes precedence) · CPC title

• H10N30/101

  with electrical and mechanical input and output, e.g. having combined actuator and sensor parts · CPC title

• H10N30/2048

  having non-planar shape · CPC title