Photoacoustic sensor valve

Patent metadata

Field	Value
Publication number	US-11788990-B2
Application number	US-202217647403-A
Country	US
Kind code	B2
Filing date	Jan 7, 2022
Priority date	Apr 3, 2019
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

A system for measuring gas concentration includes a package having a cavity and a port, a photoacoustic gas sensor device within the package, and a Micro Electro Mechanical System (“MEMS”) valve separate from the photoacoustic gas sensor device placed over the port of the package and to allow ambient gas diffusion into the cavity in a first mode of operation, and to prevent ambient gas diffusion into the cavity and to acoustically isolate the cavity in a second mode of operation.

First claim

What is claimed is:

1. A Micro Electro Mechanical System (“MEMS”) valve comprising a first perforated backplate and a perforated membrane, wherein perforations in the first perforated backplate and perforations in the perforated membrane are non-overlapping in a plan view, and wherein the perforated membrane and the first perforated backplate are in an open configuration in a first mode of operation and in a closed configuration in a second mode of operation; and a second perforated backplate, and wherein the perforated membrane is between the first perforated backplate and the second perforated backplate.

2. The MEMS valve of claim 1 , wherein a gap length between the first perforated backplate and the perforated membrane is different from a gap length between the second perforated backplate and the perforated membrane.

3. The MEMS valve of claim 1 , wherein the first perforated backplate comprises a perforated insulated silicon layer, and wherein the perforated membrane comprises a perforated silicon layer.

4. The MEMS valve of claim 1 , further comprising a cantilevered silicon substrate under the first perforated backplate and the perforated membrane.

5. The MEMS valve of claim 1 , wherein the perforations in the first perforated backplate are arranged in a hexagonal or circular radial concentric pattern, and the perforations in the perforated membrane are arranged in a non-overlapping hexagonal or circular radial concentric pattern.

6. A PhotoAcoustic Sensor (“PAS”) valve comprising:
a first membrane comprising an inner concentric pattern of perforations and an outer circular ring without perforations; and
a second membrane comprising a circular inner portion without perforations, a first outer circular ring having a concentric pattern of perforations, and a second outer circular ring without perforations,
wherein the inner concentric pattern of perforations of the first membrane and the concentric pattern of perforations of the second membrane are nonoverlaping in a plan view.

7. The PAS valve of claim 6 , wherein the first membrane comprises a rigid backplate and the second membrane comprises a flexible membrane.

8. The PAS valve of claim 6 , wherein the first membrane comprises a flexible membrane and the second membrane comprises a rigid backplate.

9. The PAS valve of claim 6 , wherein the inner concentric pattern of perforations of the first membrane comprises a circular radial concentric pattern of perforations.

10. The PAS valve of claim 6 , wherein the inner concentric pattern of perforations of the first membrane comprises a hexagonal radial concentric pattern of perforations.

11. The PAS valve of claim 6 , wherein the first membrane comprises a circular bumpring.

12. The PAS valve of claim 11 , wherein the circular bumpring is not in contact with the second membrane in a first mode of operation of the PAS valve.

13. The PAS valve of claim 12 , wherein the circular bumpring is in contact with the second membrane in a second mode of operation of the PAS valve.

14. A monolithic acoustic valve comprising:
a perforated insulated silicon backplate coupled to a substrate; and
a perforated silicon membrane coupled to the substrate,
wherein perforations in the perforated insulated silicon backplate and non-overlapping perforations in the perforated silicon membrane comprise a radial pattern emanating from a center portion of the monolithic acoustic valve to a peripheral portion of the monolithic acoustic valve in a plan view, and wherein the radial pattern comprises an inner pattern and a non-overlapping outer ringed pattern.

15. The monolithic acoustic valve of claim 14 , further comprising an additional perforated insulated silicon backplate coupled to the substrate and adjacent to the perforated silicon membrane.

16. The monolithic acoustic valve of claim 14 , wherein the inner pattern comprises a circular or hexagonal pattern on the perforated insulated silicon backplate.

17. The monolithic acoustic valve of claim 14 , wherein the inner pattern comprises a circular or hexagonal pattern on the perforated silicon membrane.

18. The monolithic acoustic valve of claim 14 , wherein the perforated insulated silicon backplate comprises an insulated anti-sticking bump ring and/or a plurality of insulated anti-sticking bumps.

19. The monolithic acoustic valve of claim 14 , wherein the substrate comprises a cantilevered silicon substrate.

Assignees

• Infineon Technologies Ag

Inventors

• Manz Johannes
• Klein Wolfgang
• Tumpold David

Classifications

• G01N29/2425 Primary

  optoacoustic fluid cells therefor · CPC title

• G01N1/22

  in the gaseous state {(specially adapted for biological material G01N33/497; measuring breath flow A61B5/087)} · CPC title

• G01N21/1702 Primary

  with opto-acoustic detection, e.g. for gases or analysing solids · CPC title

• G01N1/2273

  Atmospheric sampling · CPC title

• G01N2021/1704

  in gases · CPC title