阅读说明：本技术 用于低密度材料的低阻抗传感器 (Low impedance sensor for low density materials ) 是由 J·C·巴特 J·C·程 E·P·李 于 2019-01-22 设计创作，主要内容包括：一种具有小的物理占用空间的电化学气体传感器装置被公开。元件内的电极被围绕电解质布置以使得所述传感器的电阻抗最小化。这导致在检测到气体之后快速稳定,并且使得偏置电压能够迅速改变以针对不同的气体。衬垫元件或可替换的设计被包括以消除电池内的电极之间的气体的扩散。(An electrochemical gas sensor device having a small physical footprint is disclosed. Electrodes within the element are arranged around the electrolyte to minimize the electrical impedance of the sensor. This results in rapid settling after the gas is detected and enables the bias voltage to be changed rapidly to target different gases. A spacer element or alternative design is included to eliminate diffusion of gases between electrodes within the cell.)

1. An electrochemical sensing device, comprising:

packaging the panel;

a cover panel;

a solid or semi-solid electrolyte;

a plurality of electrodes disposed in one or more electrode chambers, each electrode in contact with the electrolyte;

the plurality of electrodes, at least one of which is in gaseous communication with an external environment through a gas port through-hole in one of the panels; and

a seal that gas-isolates at least one electrode compartment from any other electrode compartment.

2. The apparatus of claim 1, wherein the lid panel and package panel are at least partially bonded to each other with an adhesive material.

3. The device of claim 1, the electrodes and electrolyte comprising an electrochemical sensor disposed within a sensor chamber at least partially defined by the lid panel and the packaging panel, the electrochemical sensor being voltage biased by one or more electrical contacts and delivering an electrical sensor output signal responsive to a chemical interaction of one or more of the electrodes, the electrolyte, and a sensed gas within the electrode chamber.

4. The device of claim 1, comprising a plurality of electrode chambers including a working electrode chamber, the plurality of electrode chambers being gas isolated from each other to substantially prevent leakage or diffusion of gas between the electrode chambers.

5. The device of claim 4, said electrolyte comprising a solid or semi-solid layer disposed between at least two such electrode compartments, the electrolyte layer acting to block gas diffusion between said at least two such electrode compartments.

6. The apparatus of claim 1, the seal comprising a gasket material to achieve the gas barrier.

7. The device of claim 1, the seal being disposed between portions of the package panel and the lid panel to block gas diffusion between one or more electrode compartments and any other electrode compartments of the device.

8. The device of claim 1, the seal being disposed between a portion of the package panel or the lid panel and the electrolyte to block gas diffusion between one or more electrode compartments and any other electrode compartments of the device.

9. The apparatus of claim 8, the seal comprising a gasket material to achieve the gas isolation.

10. The apparatus of claim 6, the gasket material comprising any one of: fluoropolymers, fluorosilicones, polyimides, butyl or other rubber compounds, rubber derivatives, epoxies, silicones, and acrylics.

11. The device of claim 1, the cover panel and the package panel contacting each other at portions thereof to block gas diffusion between at least one electrode compartment and any other electrode compartment of the device.

12. The device of claim 1, further comprising a gas permeable filter that filters gas passing through the gas port through-holes.

13. The device of claim 1, further comprising a plurality of electrical contacts and conductive vias coupling the electrodes to respective external connection points on the device.

14. The apparatus of claim 13, further comprising an integrated circuit disposed on an exterior face of the apparatus and electrically coupled to the electrical contacts.

15. The apparatus of claim 14, the integrated circuit comprising an Application Specific Integrated Circuit (ASIC).

16. The device of claim 1, further comprising at least one additional gas port through hole in any one of the package panel and the cap panel, the at least one additional gas port placing a respective electrode of the device in gaseous communication with an external environment.

17. The apparatus of claim 1, the electrolyte comprising an electrolyte layer disposed between the package panel and the lid panel in substantially parallel planes, the electrode further comprising a planar structure in contact with the electrolyte layer on at least one side of the electrolyte layer.

18. The device of claim 17, wherein one or more of the electrodes are oriented and positioned with an overlap region separated from the working electrode by the electrolyte layer.

19. The device of claim 18, the one or more electrodes overlapping the working electrode being oriented orthogonal to the working electrode in their respective planes.

20. The device of claim 18, the one or more electrodes overlapping the working electrode being oriented parallel to the working electrode in their respective planes.

21. The device of claim 20, comprising a reference electrode disposed directly opposite the working electrode, the reference electrode and the working electrode separated by an electrolyte material.

22. The device of claim 20, comprising a counter electrode disposed laterally to the electrolyte material beside and on the same side as the working electrode.

23. The device of claim 20, comprising a counter electrode disposed laterally to and opposite the working electrode with respect to the electrolyte material.

24. The apparatus of claim 1, the at least one gas-isolated electrode compartment comprising a working electrode compartment.

25. The apparatus of claim 1, the at least one gas-isolated electrode chamber comprising a reference electrode chamber.

26. A method for fabricating an electrochemical sensor device having a plurality of sensor electrodes, the method comprising:

forming a package panel;

forming a lid panel;

creating a plurality of vias in at least one of the lid panel and the package panel, the plurality of vias including a gas port via connecting at least one electrode chamber containing a respective electrode with an external environment;

forming one or more gas seals on an interior face of at least one of the panels to gas isolate at least the electrode compartment from any other electrode compartment;

attaching electrical contacts to one or both of the lid panel and the package panel;

forming a solid or semi-solid electrolyte layer disposed between a plurality of electrodes including the electrode and a further electrode; and

engaging an interior face of the lid panel and an interior face of the package panel to define the electrode compartment and any other electrode compartments, wherein the respective electrodes and other electrodes simultaneously contact the solid or semi-solid electrolyte layer.

27. The method of claim 26, further comprising sealing one or more of the electrode chambers with a gasket in direct contact with the electrolyte.

28. The method of claim 26, further comprising applying an adhesive at selected locations to bond the lid panel and the package panel.

29. The method of claim 26, further comprising installing a gas filter on the gas port through-hole.

30. The method of claim 26, further comprising orienting at least one other electrode orthogonal to the working electrode in a respective parallel plane and separated from the working electrode by the electrolyte layer.

31. The method of claim 26, further comprising orienting at least one other electrode parallel to the respective electrode in a respective parallel plane and separated from the electrode by the electrolyte layer.

Technical Field

The present invention relates to sensing and identification of low density materials, such as gases, in particular by electrochemical cells in combination with sensing circuitry having low electrical impedance.

Background

Given the changes in the earth's atmosphere due to industrialized and natural resources, as well as the drastically increasing number of sources of household and urban pollution, the need for accurate and continuous air quality monitoring has become a necessary condition for determining sources and alerting consumers to impending dangers. Making real-time monitoring and exposure assessment practical is the ability to provide low cost, small form factor and low power devices that can be integrated into the broadest range of platforms and applications.

There are a number of ways to sense different low density materials, such as gases. Common methods include non-dispersive infrared spectroscopy (NDIR), the use of metal oxide sensors, the use of chemiresistors, and the use of electrochemical sensors. The present invention relates to electrochemical sensors.

One drawback of conventional electrochemical sensors is that their size (e.g., the volume of the electrolyte and the size of the electrodes) is relatively large, such that it takes a long time to settle when subjected to the target gas. Furthermore, the signal-to-noise ratio is low because the change in current in response to the gas is small, and there are losses and RF coupling due to metal traces to processing circuitry outside the sensor, which further reduces the signal-to-noise ratio. In addition, the electrochemical cell body is typically a polymer that cannot withstand temperatures above 150 ℃, and the electrolyte comprises an aqueous solution of an acid that cannot withstand temperatures above about 100 ℃. This prevents the electrical contacts from being soldered to the printed circuit board by reflowing the solder (typically at 180-260 c) and prevents the use of some thermosetting conductive adhesives (such as silver-containing epoxy, or anisotropic conductive films or pastes) that are typically cured at 120-150 c.

There are a number of ways to sense different low density materials, such as gases. Common methods include non-dispersive infrared spectroscopy (NDIR), the use of metal oxide sensors, the use of chemiresistors, and the use of electrochemical sensors. Some electrochemical sensors are also known to those skilled in the art. In this application we describe the improved, small form factor electrochemical sensor devices that can be produced as individual components or integrated prior to singulation. The device of the present application may be effectively incorporated into other electronic products, such as mobile devices, and may also conform to modern standards for operating in challenging environments, including humid and/or dusty environments.

SUMMARY

The following description and the annexed drawings set forth in detail certain illustrative implementations of the disclosure, which are indicative of several exemplary ways in which the various principles of the disclosure may be carried out. However, the illustrative examples are not exhaustive of the many possible embodiments of the disclosure. Other objects, advantages and novel features of the disclosure will be set forth in the following detailed description of the disclosure when considered in conjunction with the drawings.

One aspect of the invention described herein is the physical arrangement of the electrodes in an electrochemical cell relative to the electrolyte that minimizes the electrical impedance of the cell. This in turn enables the electrochemical cell to respond more quickly to changes in the applied bias voltage. Another aspect is the physical arrangement of the electrolyte in an electrochemical cell that eliminates diffusion of gases between the electrodes.

Some embodiments are directed to an electrochemical sensing device comprising: packaging the panel; a cover panel; a solid or plate solid electrolyte; a plurality of electrodes disposed in one or more electrode chambers, each electrode in contact with the electrolyte; a plurality of electrodes in gaseous communication with an external environment through gas port through holes in one of the panels; and a seal that gas-isolates at least one electrode compartment from any other electrode compartment.

Other embodiments are directed to a method for making an electrochemical sensor device having a plurality of sensor electrodes, the method comprising: forming a package panel; forming a lid panel; creating a plurality of vias in at least one of the lid panel and the package panel, the plurality of vias including a gas port via connecting at least one electrode chamber containing a respective electrode with an external environment; forming one or more gaskets (gaskets) on an interior face of at least one of the panels to gas isolate at least the electrode compartment from any other electrode compartment; attaching electrical contacts to one or both of the lid panel and the package panel; forming a solid or semi-solid electrolyte layer disposed between a plurality of electrodes including the electrode and a further electrode; and engaging an interior face of the lid panel and an interior face of the package panel to define the electrode compartment and any other electrode compartments, wherein the respective electrodes and other electrodes simultaneously contact the solid or semi-solid electrolyte layer.