Wafer arrangement

Patent metadata

Field	Value
Publication number	US-2019323947-A1
Application number	US-201916456361-A
Country	US
Kind code	A1
Filing date	Jun 28, 2019
Priority date	Mar 27, 2015
Publication date	Oct 24, 2019
Grant date	—

Abstract

Shown is a wafer arrangement for a gas sensor including a first substrate and a sescond substrate. The first substrate includes a MEMS membrane associated with a sensor element and an emitter element configured to emit electromagnetic radiation. The second substrate is arranged on top of the first substrate and defines at least a portion of a chamber disposed adjacent to the MEMS membrane.

First claim

1 . A photoacoustic sensor device comprising:
a wafer arrangement, comprising:
a first substrate, comprising:
a MEMS membrane associated with a sensor element; and
an emitter element configured to emit electromagnetic radiation; and

a second substrate arranged on top of the first substrate, wherein the second substrate defines at least a portion of a chamber disposed adjacent to the MEMS membrane.

2 . The photoacoustic sensor device as claimed in claim 1 , wherein the MEMS membrane is configured to convert energy of the electromagnetic radiation into an output signal.

3 . The photoacoustic sensor device as claimed in claim 1 , wherein the MEMS membrane is configured to have a deflection which is dependent on an energy of the electromagnetic radiation.

4 . The photoacoustic sensor device as claimed in claim 1 , wherein the emitter element is embodied to emit the electromagnetic radiation in a pulsating manner with a frequency that is greater than 0.1 Hz or greater than 0.5 Hz or greater than 1 Hz.

5 . The photoacoustic sensor device as claimed in claim 1 , further comprising a third substrate arranged under the first substrate, wherein the third substrate defines at least a portion of a pressure equalization chamber disposed adjacent to the MEMS membrane.

6 . The photoacoustic sensor device as claimed in claim 1 , wherein the second substrate further comprises a shadow mask arranged above the MEMS membrane.

7 . The photoacoustic sensor device as claimed in claim 1 , wherein the second substrate further comprises a counter electrode arranged above the MEMS membrane.

8 . The photoacoustic sensor device as claimed in claim 1 , wherein the second substrate further comprises at least one spacer protruding from a periphery of a top surfae of the second substrate opposite the first substrate.

9 . The photoacoustic sensor device as claimed in claim 1 , wherein the emitter element and the sensor element are arranged in a projection plane extending laterally with respect to the emitter element and the sensor element, wherein the emitter element and the sensor element are arranged in a housing which is embodied to reflect the electromagnetic radiation in the emitter element onto the sensor element.

10 . The photoacoustic sensor device as claimed in claim 1 , wherein the emitter element and the sensor element are arranged in a projection plane extending in a thickness direction with respect to the emitter element and the sensor element.

11 . A method, comprising:
providing a wafer arrangement including a second substrate disposed on top of a first substrate, wherein
a first portion of the first substrate that overlies a first portion of the second substrate and comprises a MEMS membrane associated with a sensor element; and
a second portion of the first substrate that overlies a second portion of the first substrate and comprises an emitter element configured to emit electromagnetic radiation, and
the first portion of the second substrate defines at least a portion of a chamber disposed adjacent to the MEMS membrane;
separating the first portion of the first substrate and the second substrate from the second portion of the first substrate and the second substrate to form a first gas sensor layer and a second gas sensor layer; and stacking the first gas sensor layer on the second gas sensor layer to form a gas sensor.

12 . The method of claim 11 , wherein the separating comprises breaking the wafer arrangement along sawmarks in the wafer arrangement.

13 . The method of claim 11 , further comprising stacking the the first gas sensor layer on the second gas sensor layer such that a top surface of the first portion of the second substrate faces a top surface of the second portion of the second substrate.

14 . The method of claim 13 , wherein the second substrate includes at least one spacer disposed at a periphery of the first portion of the second substrate or the second portion of the second substrate and wherein the method comprises stacking the the first gas sensor layer on the second gas sensor layer such that the at least one spacer forms a wall of a measurement chamber.

15 . The method of claim 11 , further comprising stacking the the first gas sensor layer on the second gas sensor layer such that a top surface of the second portion of the second substrate faces a top surface of the second portion of the second substrate.

16 . A gas sensor, comprising:
a sensor layer comprising a first portion of a second substrate arranged on a first portion of a first substrate; an emitter layer comprising a second portion of the second substrate arranged on a second portion of the first substrate; wherein
the first portion of the first substrate comprises a MEMS membrane associated with a sensor element; and
the second portion of the first substrate comprises an emitter element configured to emit electromagnetic radiation, and
the first portion of the second substrate defines at least a portion of a chamber disposed adjacent to the MEMS membrane.

17 . The gas sensor as claimed in claim 16 , wherein the MEMS membrane is configured to convert energy of the electromagnetic radiation into an output signal.

18 . The gas sensor as claimed in claim 16 , wherein the MEMS membrane is configured to have a deflection which is dependent on an energy of the electromagnetic radiation.

19 . The gas sensor as claimed in claim 16 , wherein the emitter element is embodied to emit the electromagnetic radiation in a pulsating manner with a frequency that is greater than 0.1 Hz or greater than 0.5 Hz or greater than 1 Hz.

20 . The gas sensor as claimed in claim 16 , wherein the first portion of the second substrate further comprises a shadow mask arranged above the MEMS membrane.

21 . The gas sensor as claimed in claim 16 , wherein the first portion of the second substrate further comprises a counter electrode arranged above the MEMS membrane.

Assignees

• Infineon Technologies Ag
• Fraunhofer Ges Forschung

Inventors

• Kolb Stefan
• Dehe Alfons
• Huber Jochen
• Jost Franz
• Theuss Horst
• Wiedmeier Wilhelm
• Woellenstein Juergen

Classifications

• G01N29/2418

  using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics (photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046) · CPC title

• G01N29/022

  Fluid sensors based on microsensors, e.g. quartz crystal-microbalance [QCM], surface acoustic wave [SAW] devices, tuning forks, cantilevers, flexural plate wave [FPW] devices (microdevices per se B81B) · CPC title

• G01N2021/1704

  in gases · CPC title

• G01N21/1702 Primary

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

• G01N29/30

  Arrangements for calibrating or comparing, e.g. with standard objects · CPC title