Miniature electrochemical three-electrode test chip
The micro-electrochemical three-electrode test chip designed using microelectrode array technology solves the problem of insufficient miniaturization of the reference electrode and counter electrode in the traditional electrochemical three-electrode system, realizes the complete miniaturization and integration of the three electrodes, improves the sensitivity and accuracy of detection, and enhances the application potential of high-precision electrochemical detection.
Patent Information
- Application Number
- CN202422013649.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-20
- Publication Date
- 2025-09-05
- Estimated Expiration
- 2034-08-20
AI Technical Summary
In traditional electrochemical three-electrode systems, insufficient research has been conducted on the miniaturization and integration of reference and counter electrodes, resulting in low system integration, increased internal resistance, and limited detection sensitivity and accuracy, which restricts the application potential of high-precision electrochemical detection.
Using microelectrode array technology, a micro electrochemical three-electrode test chip integrating a working electrode, a reference electrode, and a counter electrode was designed. By designing multiple site areas on the chip, each site area integrates a working electrode, a reference electrode, and a counter electrode, ensuring a regular layout and size matching between the electrodes, thereby achieving complete miniaturization and integration of the three electrodes.
The complete miniaturization and integration of the three electrodes is achieved, which improves the sensitivity and accuracy of electrochemical detection, ensures the reliability of potential measurement, reduces the interference of the working electrode reaction on the measurement signal, and enhances the application potential of high-precision electrochemical detection.
Smart Images
Figure CN223308148U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of test chips, and in particular relates to a micro electrochemical three-electrode test chip. Background Art
[0002] The electrochemical three-electrode system, as the core configuration of electrochemical detection, is widely used in a variety of fields, including materials testing, bioelectronics, environmental monitoring, and energy storage and conversion. This system typically consists of a working electrode (WE), a reference electrode (RE), and a counter electrode (CE), which together form the basic unit of an electrochemical cell.
[0003] The working electrode (WE) is the primary site of electrochemical reactions, and its performance directly impacts detection sensitivity and accuracy. The reference electrode (RE) provides a stable potential reference, ensuring the reliability of measurement results. The counter electrode (CE) assists in completing the circuit and maintaining current flow. In practical applications, the coordinated operation of these three elements is key to achieving accurate electrochemical detection.
[0004] However, the traditional electrochemical three-electrode system has some limitations. First, the existing microelectrode array (MEA) technology mainly focuses on the miniaturization of the working electrode, while the miniaturization and integration of the reference electrode and counter electrode are relatively less studied. As a result, the use of traditional large metal electrodes in high-precision electrochemical detection limits the system's integration and detection sensitivity. Secondly, the large reference electrode and counter electrode are not sized to match the miniaturized working electrode, which not only increases the internal resistance of the system but may also affect the kinetics of the electrochemical reaction and reduce the accuracy of the test results. In addition, the traditional microelectrode array technology has failed to achieve the full integration of the three-electrode system, which to some extent limits its potential in a wider range of high-precision electrochemical detection applications.
[0005] In order to improve the performance of electrochemical detection, it is necessary to design an electrochemical test chip that can integrate a working electrode, a reference electrode, and a counter electrode. Utility Model Content
[0006] The utility model provides a micro electrochemical three-electrode test chip. The chip adopts microelectrode array technology to achieve complete miniaturization and integration of the three electrodes.
[0007] Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention.
[0008] In order to achieve one or part or all of the above purposes or other purposes, a technical solution of the present invention provides a micro electrochemical three-electrode test chip, including a substrate with a metal electrode layer; an array of sites is provided on the reference electrode layer of the substrate, and the site area exposes the working electrode layer and the counter electrode layer; a first insulating layer is provided on the reference electrode layer, and a plurality of through holes are opened on the first insulating layer, and the plurality of through holes are respectively connected to the working electrode layer, the counter electrode layer and the reference electrode layer, and the through hole areas after connection form the working electrode, the counter electrode and the reference electrode in sequence. The beneficial effect of this technical solution is that the present utility model patent designs a plurality of sites on the chip by designing the structure of the chip, and each site area integrates the working electrode, the reference electrode and the counter electrode, and each site area can independently perform electrochemical testing.
[0009] The working electrode is arranged adjacent to the reference electrode.
[0010] The plurality of through holes include working electrodes or counter electrodes formed on the site area and connected to the working electrode layer or counter electrode layer exposed on the site area; the through holes also include reference electrodes formed by connecting to the reference electrode layer.
[0011] The reference electrode layer is provided with a plurality of circular sites, one corner of each circular site is formed with a notch; the plurality of circular sites form a square array.
[0012] The reference electrode is formed at the notch of the circular site, and the working electrode is adjacent to the reference electrode.
[0013] The centers of the sites are arranged at equal distances, and the distance between the centers of the sites is at least greater than 30 μm.
[0014] The working electrode layer and the counter electrode layer are located in the same layer, and a second insulating layer is provided between the working electrode layer and the counter electrode layer, and between the reference electrode layer and the working electrode layer and the counter electrode layer.
[0015] The area of the counter electrode is at least ten times that of the working electrode.
[0016] The working electrode layer, the reference electrode layer and the counter electrode layer are respectively connected to the working electrode metal lead layer, the reference electrode metal lead layer and the counter electrode metal lead layer formed on the substrate; the working electrode metal lead layer, the reference electrode metal lead layer and the counter electrode metal lead layer are arranged on the third insulating layer of the substrate in the same layer.
[0017] The working electrode metal lead layer, the reference electrode metal lead layer and the counter electrode metal lead layer are connected to the bonding pads of the chip through metal connecting wires.
[0018] Compared with the existing technology, the beneficial effects of the present invention mainly include: 1. The electrochemical three-electrode test chip of the present invention uses microelectrode array technology to achieve complete miniaturization and integration of three electrodes. A complete three-electrode test function is integrated in each site area of the chip, and each site can perform electrochemical tests independently and in parallel;
[0019] 2. The sites are arranged in a square array with regular distances between the centers of the sites, forming a high-density electrode array;
[0020] 3. By optimizing the electrode size and layout, the reference electrode and the working electrode are placed adjacent to each other, ensuring the accuracy of potential measurement; the area of the counter electrode is at least ten times that of the working electrode, ensuring that the reaction rate of the counter electrode is higher than that of the working electrode, reducing the interference of the working electrode reaction on the measurement signal.
[0021] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below with reference to the accompanying drawings for detailed description. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0023] Figure 1 The figure shows the cross section of the chip at each site area.
[0024] Figure 2 This is a schematic diagram of the front of the chip of this utility model.
[0025] In the figure, 1 is the substrate; 2 is the third insulating layer; 3 is the reference electrode metal lead layer; 4 is the fourth insulating layer; 5 is the working electrode metal lead layer; 6 is the working electrode layer; 7 is the counter electrode layer; 8 is the counter electrode metal lead layer; 9 is the metal connecting wire; 10 is the reference electrode; 11 is the working electrode; 12 is the counter electrode; 13 is the second insulating layer; 14 is the reference electrode layer; 15 is the first insulating layer; 16 is the site. DETAILED DESCRIPTION
[0026] The aforementioned and other technical aspects, features, and functions of the present invention are clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. Directional terms such as up, down, left, right, front, and back, used in the following embodiments, are merely references to the directions in the accompanying drawings. Therefore, the directional terms used are for illustrative purposes only and are not intended to limit the present invention.
[0027] Example 1
[0028] Example 1 provides a novel micro electrochemical three-electrode test chip. Figure 1 as well as Figure 2 , see Figure 1 The chip's structure diagram shows a substrate 1 on which a metal electrode layer has been deposited. The metal electrode layer includes a working electrode layer 6, a counter electrode layer 7, and a reference electrode layer 14. The reference electrode layer 14 is located at the outermost layer of the metal electrode layer. A first insulating layer 15 is also provided on the reference electrode layer 14. A site 16 is formed on the reference electrode layer 14 by dry etching. The site 16 is in the shape of a circle with a square notch. After dry etching, the site 16 exposes the working electrode layer 6 and the counter electrode layer 7. The working electrode layer 6 and the counter electrode layer 7 are located on the same layer and are separated by a second insulating layer 13. The first insulating layer 15 located on the reference electrode layer 14 is relatively thin, and the shape of the site 16 can be seen through the first insulating layer 15. At the same time, when the first insulating layer 15 covers the reference electrode layer 14, it covers the circular hollow area of the reference electrode layer 14, facilitating the subsequent etching of the first insulating layer 15 to form an electrode pattern.
[0029] The sites 16 are in an array, and each site 16 is a circle with a square notch. The shape of the notch is not limited. In addition to the square in Example 1, it can also be other shapes. The position of the notch is to facilitate the formation of the reference electrode 10. The center of each site 16 is arranged equidistantly, and multiple sites 16 are in a square array. Figure 2 The array shape given in the figure is 2*2. In practice, a 16-site array can have more 16 sites. The more 16 sites there are, the higher the flux of the chip. The sites are in a square array with regular distances between the centers of the sites, which can form a high-density electrode array.
[0030] A plurality of through holes are opened on the first insulating layer 15 to form the reference electrode 10, the working electrode 11 and the counter electrode 12. Specifically, a through hole is opened at each site area, including a through hole connected to the working electrode layer 6 and the counter electrode layer 7 inside the site 16 area (a hole is opened on the first insulating layer 15 until the working electrode layer 6 and the counter electrode layer 7 are exposed). The area of the two through holes is the working electrode 11 and the counter electrode 12. At the same time, there is a square notch in the circular site 16. The square notch is formed during etching (the notch area is not hollowed out, i.e., the reference electrode layer 14). When the first insulating layer 15 is opened, a through hole is opened in the square notch area to connect to the reference electrode layer 14. The through hole area is the reference electrode 10. The utility model provides through holes on the first insulating layer 15 for patterning, exposing the conductive surfaces of the working electrode layer 6, the counter electrode layer 7 and the reference electrode layer 14. A second insulating layer 13 and a fourth insulating layer 15 are provided extending upward from the conductive surfaces of the working electrode layer 6, the counter electrode layer 7 and the reference electrode layer 14 to separate the working electrode layer 6, the counter electrode layer 7 and the reference electrode layer 14 to avoid affecting the operation of the electrodes.
[0031] The electrochemical three-electrode test chip of the present invention uses microelectrode array technology to integrate the reference electrode 10, the working electrode 11 and the counter electrode 12 in the area of site 16 (although the reference electrode 10 is not in site 16, it is adjacent to the site, and the three electrodes can be considered to be integrated in the area of site 16), realizing the complete miniaturization and integration of the three electrodes. A complete three-electrode test function is integrated in each site area of the chip, and each site can perform electrochemical tests independently and in parallel. The working electrode 11 is arranged adjacent to the reference electrode 10 to ensure the accuracy of the potential measurement. The area of the counter electrode 12 is larger than the area of the working electrode 11, and the area of the counter electrode 12 is at least ten times the area of the working electrode 11. This arrangement is to ensure that the reaction rate of the counter electrode 12 is higher than that of the working electrode 11, reducing the interference of the reaction of the working electrode 11 on the measurement signal.
[0032] See also Figure 1 , Figure 1It is a side view of the interface of any site 16, in which the working electrode layer 6, the counter electrode layer 7 and the reference electrode layer 14 are connected to the working electrode metal lead layer 5, the counter electrode metal lead layer 8 and the reference electrode metal lead layer 3 respectively. The working electrode metal lead layer 5, the counter electrode metal lead layer 8 and the working electrode layer 6 and the counter electrode layer 7 are separated by a fourth insulating layer 4, and a through hole is provided on the fourth insulating layer 4 for connecting the working electrode metal lead layer 5, the counter electrode metal lead layer 8 and the working electrode layer 6 and the counter electrode layer 7. The reference electrode metal lead layer 3 is also provided on the same layer as the working electrode metal lead layer 5 and the counter electrode metal lead layer 8, and the working electrode metal lead layer 5, the counter electrode metal lead layer 8 and the reference electrode metal lead layer 3 are all provided on the third insulating layer 2 of the substrate. A metal connecting wire 9 is also provided on the substrate, and the metal connecting wire 9 is used to connect the working electrode metal lead layer 5, the counter electrode metal lead layer 8 and the reference electrode metal lead layer 3 to the bonding pad of the chip.
[0033] The above is a detailed introduction to the micro electrochemical three-electrode test chip provided by the present invention. This article uses specific examples to illustrate the structure and working principle of the present invention. The description of the above embodiments is only intended to help understand the method and core concept of the present invention. It should be noted that for those skilled in the art, without departing from the principles of the present invention, various improvements and modifications can be made to the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.
Claims
1. A micro electrochemical three-electrode test chip, characterized in that: A substrate including a metal electrode layer; An array of sites is provided on the reference electrode layer of the substrate, wherein the working electrode layer and the counter electrode layer are exposed in the site area; A first insulating layer is provided on the reference electrode layer, and a plurality of through holes are opened on the first insulating layer. The plurality of through holes are respectively connected to the working electrode layer, the counter electrode layer and the reference electrode layer, and the connected through hole areas sequentially form the working electrode, the counter electrode and the reference electrode.
2. A micro electrochemical three-electrode test chip according to claim 1, characterized in that: The working electrode is arranged adjacent to the reference electrode.
3. A micro electrochemical three-electrode test chip according to claim 2, characterized in that: The plurality of through holes are formed on the site area and communicate with the working electrode layer or the counter electrode layer exposed on the site area to form the working electrode or the counter electrode; The through hole further includes a reference electrode connected to the reference electrode layer.
4. A micro electrochemical three-electrode test chip according to claim 3, characterized in that: The reference electrode layer is provided with a plurality of circular sites, and a notch is formed at a corner of the circular site; A plurality of the circular sites form a square array.
5. The micro electrochemical three-electrode test chip according to claim 4, characterized in that: The reference electrode is formed at the notch of the circular site, and the working electrode is adjacent to the reference electrode.
6. The micro electrochemical three-electrode test chip according to claim 4, characterized in that: The centers of the sites are arranged at equal distances, and the distance between the centers of the sites is at least greater than 30 μm.
7. The micro electrochemical three-electrode test chip according to claim 1, characterized in that: The working electrode layer and the counter electrode layer are located in the same layer, and a second insulating layer is provided between the working electrode layer and the counter electrode layer, and between the reference electrode layer and the working electrode layer and the counter electrode layer.
8. The micro electrochemical three-electrode test chip according to claim 1, characterized in that: The area of the counter electrode is at least ten times that of the working electrode.
9. The micro electrochemical three-electrode test chip according to claim 1, characterized in that: The working electrode layer, the reference electrode layer and the counter electrode layer are respectively connected to the working electrode metal lead layer, the reference electrode metal lead layer and the counter electrode metal lead layer formed on the substrate; The working electrode metal lead layer, the reference electrode metal lead layer and the counter electrode metal lead layer are arranged on the third insulating layer of the substrate in the same layer.
10. The micro electrochemical three-electrode test chip according to claim 9, characterized in that: The working electrode metal lead layer, the reference electrode metal lead layer and the counter electrode metal lead layer are connected to the bonding pads of the chip through metal connecting wires.