Heat flux sensor device and method of manufacture thereof

Patent metadata

Field	Value
Publication number	US-2025369808-A1
Application number	US-202519204847-A
Country	US
Kind code	A1
Filing date	May 12, 2025
Priority date	Jun 3, 2024
Publication date	Dec 4, 2025
Grant date	—

Abstract

A heat flux sensor device (100) comprising a semiconductor substrate layer (104) and a cap layer (102) that has a substrate-facing side (106) and a reception side (108). The cap layer (102) is bonded on the substrate-facing side (106) to the substrate layer (104), and the substrate layer (104) and the cap layer (102) together defining a first cavity (116). A first thermal sensor element (120, 122) is disposed within the first cavity (116) and configured to translate thermal energy proportional to a temperature difference between the cap layer (102) and the substrate layer (104) into first electrical energy. Signal processing circuitry is provided operably coupled to the first thermal sensor element (120, 122) and configured to use the first electrical energy generated by the first thermal sensor element (120, 122) to measure a heat flux flowing from the cap layer (102) to the substrate layer (104). The first cavity (116) is opaque to infrared electromagnetic radiation incident from the reception side (108) of the cap layer (102).

First claim

What is claimed is:

1 . A heat flux sensor device comprising:
a semiconductor substrate layer; a cap layer having a substrate-facing side and a reception side, the cap layer being bonded on the substrate-facing side thereof to the semiconductor substrate layer, and the semiconductor substrate layer and the cap layer together defining a first cavity; a first thermal sensor element disposed within the first cavity and configured to translate, when in use, thermal energy proportional to a temperature difference between the cap layer and the semiconductor substrate layer into first electrical energy; and signal processing circuitry operably coupled to the first thermal sensor element and configured to use the first electrical energy generated, when in use, by the first thermal sensor element to measure a heat flux flowing from the cap layer to the semiconductor substrate layer; wherein the first cavity is opaque, when in use, to infrared electromagnetic radiation incident from the reception side of the cap layer.

2 . The device according to claim 1 , further comprising: a substrate temperature sensor operably coupled to the semiconductor substrate layer.

3 . The device according to claim 1 , wherein the first thermal sensor element is disposed in a plane substantially parallel with the semiconductor substrate layer and the cap layer.

4 . A thermal sensor device comprising:
the heat flux sensor device according to claim 1 ; wherein the semiconductor substrate layer and the cap layer together define a second cavity; and further comprising: a first infrared electromagnetic radiation sensor comprising the second cavity and a second thermal sensor element disposed in the second cavity, the second thermal sensor element being configured to translate thermal energy into second electrical energy.

5 . The device according to claim 4 , wherein the second cavity comprises an aperture located opposite the second thermal sensor element.

6 . The device according to claim 4 , wherein the second cavity is opaque, when in use, to infrared electromagnetic radiation incident from the reception side of the cap layer.

7 . The device according to claim 5 , wherein
the semiconductor substrate layer and the cap layer together define a third cavity; and the device further comprises: a second infrared electromagnetic radiation sensor comprising the third cavity and a third thermal sensor element disposed in the third cavity, the third thermal sensor element being configured to translate thermal energy into third electrical energy; and the third cavity is opaque, when in use, to infrared electromagnetic radiation incident from the reception side of the cap layer.

8 . The device according to claim 6 , wherein
the thermal energy is proportional to the temperature difference between the cap layer and the semiconductor substrate layer; the second thermal sensor element is operably coupled to the signal processing circuitry; and the signal processing circuitry is configured to use the second electrical energy generated by the second thermal sensor element, when in use, to measure the heat flux flowing from the cap layer to the semiconductor substrate layer.

9 . The device according to claim 7 , wherein
the thermal energy is proportional to the temperature difference between the cap layer and the semiconductor substrate layer; the third thermal sensor element is operably coupled to the signal processing circuitry; and the signal processing circuitry is configured to use the third electrical energy generated by the third thermal sensor element, when in use, to measure the heat flux flowing from the cap layer to the semiconductor substrate layer.

10 . The device according to claim 1 , wherein
the semiconductor substrate layer and the cap layer cooperate to define a hermetic local environment; and the hermetic local environment is maintained at a predetermined pressure.

11 . The device according to claim 4 , wherein
the semiconductor substrate layer and the cap layer cooperate to define a hermetic local environment; and the hermetic local environment is maintained at a predetermined pressure.

12 . The device according to claim 11 , wherein the first cavity is within and in fluid communication with the hermetic local environment.

13 . The device according to claim 12 , wherein the second cavity is within and in fluid communication with the hermetic local environment.

14 . The device according to claim 4 , wherein
the semiconductor substrate layer and the cap layer cooperate to define a first hermetic local environment and a second hermetic local environment, the first hermetic local environment being maintained at a first predetermined pressure and the second hermetic local environment being maintained at a second predetermined pressure; the second hermetic local environment is separate and independent from the first hermetic local environment; the first cavity is within and in fluid communication with the first hermetic local environment; and the second cavity is within and in fluid communication with the second hermetic local environment.

15 . The device according to claim 8 , wherein
the heat flux sensor device and the first infrared electromagnetic radiation sensor are formed in accordance with a plurality of common structural constraints; and a first value of a common structural constraint of the plurality of common structural constraints in respect of the heat flux sensor device is different from a second value of the same common structural constraint in respect of the first infrared electromagnetic radiation sensor.

16 . A thermal sensor module comprising:
a package containing the thermal sensor device according to claim 4 , wherein the package comprises a module cover opposite the reception side of the cap layer.

17 . The module according to claim 16 , further comprising:
a layer of thermal interface material disposed between the reception side of the cap layer and the module cover.

18 . The thermal sensor module according to claim 17 , wherein the layer of thermal interface material is transmissive to infrared electromagnetic radiation.

19 . The module according to claim 17 or claim 18 , wherein the layer of thermal interface material comprises an access aperture opposite the first infrared electromagnetic radiation sensor.

20 . A method of manufacturing a heat flux sensor device comprising:
providing a semiconductor substrate layer; providing a cap layer having a substrate-facing side and a reception side; forming a first thermal sensor element and a first recessed part of a first cavity in the semiconductor substrate layer, the first thermal sensor element being configured to translate, when in use, thermal energy proportional to a temperature difference between the cap layer and the semiconductor substrate layer into first electrical energy; bonding the cap layer on the substrate-facing side thereof to the semiconductor substrate layer, the first recessed part of the first cavity in the semiconductor substrate layer and the cap layer together defining the first cavity containing the first thermal sensor element; and providing signal processing circuitry operably coupled to the first thermal sensor element and configured to use the first electrical energy generated, when in use, by the first thermal sensor element to measure a heat flux flowing from the cap layer to the semiconductor substrate layer; wherein the first cavity is opaque, when in use, to in

Assignees

• Melexis Technologies Nv

Inventors

• Van Buggenhout Carl
• Buydens Luc
• Reekmans Stijn
• Van Daele Benny
• Van Thienen Jietse
• Terryn Dirk

Classifications

• G01K17/00 Primary

  Measuring quantity of heat (measuring temperature by calorimetry G01K3/00 - G01K11/00; specially adapted for measuring thermal properties of materials, e.g. specific heat, heat of combustion G01N) · CPC title

• G01J5/0025

  Living bodies (ear thermometers G01J5/0011; detecting, measuring or recording for diagnostic purposes A61B5/00) · CPC title

• G01J5/12

  using thermoelectric elements, e.g. thermocouples · CPC title

• G01J5/045

  Sealings; Vacuum enclosures; Encapsulated packages; Wafer bonding structures; Getter arrangements (getter arrangements per se H10W76/48, H10P36/03) · CPC title

• G01K13/20

  Clinical contact thermometers for use with humans or animals · CPC title