MEMS die with sensing structures

• US 10,823,692 B2
• Filed: 10/05/2016
• Issued: 11/03/2020
• Est. Priority Date: 10/06/2015
• Status: Active Grant

• Current Assignee: Carrier Corporation (Carrier Global Corporation)
• Original Assignee: Carrier Corporation (Carrier Global Corporation)
• Inventors: Christenson, John Carl, Potasek, David P., Childress, Marcus Allen
• Primary Examiner(s): McCall, Eric S.
• Assistant Examiner(s): Graves, Timothy P
• Application Number:
  US15/286,407
• Publication Number:
  US 20170097314A1
• Time in Patent Office: 1,490 Days
• CPC Class Codes: B81B 2201/00 Specific applications of microelectromechanical systems
• CPC Class Codes: B81B 2201/02 Sensors
• CPC Class Codes: B81B 2201/0214 Biosensors; Chemical sensors
• CPC Class Codes: B81B 7/02 containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] B81B7/04 takes precedence
• CPC Class Codes: G01N 27/128 Microapparatus
• CPC Class Codes: G01N 27/14 of an electrically-heated body in dependence upon change of temperature
• CPC Class Codes: G01N 33/0004 Gaseous mixtures, e.g. polluted air
• CPC Class Codes: G01N 33/0027 concerning the detector
• CPC Class Codes: G01N 33/0036 specially adapted to detect a particular component physical analysis of gaseous biological material G01N33/497

Abstract

A microelectromechanical systems die including a thermally conductive substrate including an outer surface, a plurality of low mass sensing structures disposed within the thermally conductive substrate to form a plurality of inter-structure spaces therebetween, each of the plurality of low mass sensing structures include a sensing structure proximal top surface, a sensing structure distal top surface, and a sensing structure width dimension.

Claims

1. A microelectromechanical systems die comprising:

a thermally conductive substrate including an outer surface;

a plurality of sensing structures disposed within the thermally conductive substrate to form a plurality of inter-structure spaces therebetween, each of the plurality of sensing structures include a sensing structure proximal top surface, a sensing structure distal top surface, and a sensing structure width dimension;

a sensor material disposed on at least two surfaces of each of the plurality of sensing structures, the sensor material configured to detect a target gas;

a heating apparatus disposed on each of the plurality of sensing structures;

a sacrificial coating disposed on at least one of the plurality of sensing structures, wherein the sacrificial coating is disposed over the sensor material, wherein the sacrificial coating is composed of at least one material that is burned away by the heating apparatus;

wherein each heating apparatus disposed on each of the plurality of sensing structures is independently controlled by applying a separate current to each heating apparatus to independently control a temperature of the sensor material on each sensing structure.

2. The microelectromechanical systems die of claim 1, wherein at least two of the plurality of sensing structures include a different sensing structure width dimension.

3. The microelectromechanical systems die of claim 1, wherein the thermally conductive substrate is composed of silicon.

4. The microelectromechanical systems die of claim 1, further comprising a first electrode disposed on the sensor material at the sensing structure proximal top surface, and a second electrode disposed on the sensor material at the sensing structure distal top surface.

5. The microelectromechanical systems die of claim 1, further comprising at least one dielectric film disposed over the thermally conductive substrate.

6. The microelectromechanical systems die of claim 1, further comprising a plurality of passive heat exchangers, each operably coupled to a bond pad, wherein each bond pad is disposed on each of the at least one sensing structures.

7. The microelectromechanical systems die of claim 6, wherein the bond pad is operably coupled to at least one of the at least one electrode and the heating apparatus.

8. The microelectromechanical systems die of claim 5, further comprising at least one aperture disposed within the at least one dielectric film.

9. The microelectromechanical systems die of claim 8, further comprising a bond pad disposed within the aperture, wherein the bond pad is further coupled to a passive heat exchanger.

10. The microelectromechanical systems die of claim 1 further comprising at least one channel disposed within the thermally conductive substrate, wherein the at least one channel extends from the outer surface into at least one of the plurality of inter-structure spaces.

11. The microelectromechanical systems die of claim 10, further comprising a cavity disposed within the thermally conductive substrate, the cavity disposed beneath each of the plurality of sensing structures, and in flow communication with the at least one channel.

12. The microelectromechanical systems die of claim 1, wherein the sacrificial coating is composed of at least one of an organic material and a plastic material.

13. A gas detector package comprising:

a microelectromechanical systems die comprising;

a thermally conductive substrate;

a plurality of sensing structures disposed within the thermally conductive substrate, the plurality of sensing structures including a sensing structure proximal top surface, a sensing structure distal top surface, and a sensing structure width dimension;

a sensor material disposed on at least two surfaces of each of the plurality of sensing structures, the sensor material configured to detect a target gas;

a heating apparatus disposed on each of the plurality of sensing structures;

a sacrificial coating disposed on at least one of the plurality of sensing structures, wherein the sacrificial coating is disposed over the sensor material, wherein the sacrificial coating is composed of at least one material that is burned away by the heating apparatus;

wherein each heating apparatus disposed on each of the plurality of sensing structures is independently controlled by applying a separate current to each heating apparatus to independently control a temperature of the sensor material on each sensing structure.

14. The gas detector of claim 13, wherein at least two of the plurality of sensing structures include a different sensing structure width dimension.

15. The gas detector package of claim 13, wherein the thermally conductive substrate is composed of silicon.

16. The gas detector package of claim 13, wherein the microelectromechanical systems die further comprises a first electrode disposed on the sensor material at the sensing structure proximal top surface, and a second electrode disposed on the sensor material at the sensing structure distal top surface.

17. The gas detector package of claim 13, further comprising at least one dielectric film disposed over the thermally conductive substrate.

18. The gas detector package of claim 13, wherein the microelectromechanical systems die further comprises a plurality of passive heat exchangers, each operably coupled to a bond pad, wherein each bond pad is disposed on each of the at least one sensing structures.

19. The gas detector package of claim 18, wherein the bond pad is operably coupled to at least one of the at least one electrode and the heating apparatus.

20. The gas detector package of claim 17, wherein the microelectromechanical systems die further comprises at least one aperture disposed within the at least one dielectric film.

21. The gas detector package of claim 20, further comprising a bond pad disposed within the aperture, wherein the bond pad is further coupled to a passive heat exchanger.

22. The gas detector package of claim 13, wherein the microelectromechanical systems die further comprises at least one channel disposed within the thermally conductive substrate, wherein the at least one channel extends from the outer surface into at least one of the plurality of inter-structure spaces.

23. The gas detector package of claim 13, wherein the sacrificial coating is composed of at least one of an organic material and a plastic material.