Test module of conductive anode wire
By optimizing the inner layer design of the welding hole of the conductive anode wire test module, reducing the metal area and heat dissipation, welding difficulties and pollution problems are solved, and testing accuracy and applicability are improved.
Patent Information
- Application Number
- CN202421758009.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-23
- Publication Date
- 2025-06-20
- Estimated Expiration
- 2034-07-23
AI Technical Summary
The existing conductive anode wire test module has the problem of excessive heat dissipation of welding hole positions in the hole-to-line design, which leads to welding difficulties and flux contamination, affecting the accuracy of the test.
By optimizing the inner layer design of the welding holes of the test module, the metal area between the test holes and the welding holes is reduced, the heat dissipation during welding is reduced, and flux contamination caused by repeated welding is avoided.
Reduces welding difficulty, improves the accuracy of CAF testing, and avoids flux contamination. It is suitable for hole-to-line CAF testing designs in various situations.
Smart Images
Figure CN223006267U_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present utility model relate to the technical field of test module chips, and in particular, to a test module for conductive anode filaments. Background Art
[0002] In the industry standard of Printed Circuit Board (PCB), the Conductive Anodic Filament (CAF) resistance test needs to be carried out: X - Y axis. Among them, the conductive anode filament is a type of failure caused by electrochemical reaction. This failure mode is an anode - conductive filamentous object formed by the growth of a copper - containing filamentous object inside the PCB from the anode to the cathode direction, abbreviated as CAF.
[0003] However, there are still many imperfect problems in the current CAF - related test methods, test standards, and test module designs. For the design and test of the hole wall to the inner layer line (hereinafter referred to as hole - to - line), for example, referring to Figure 1 as shown, where Figure 1 Figure (a) is a schematic diagram of the surface layer of the hole - to - line CAF test module. Figure 1 Figure (b) is a schematic diagram of the inner layer of the hole - to - line CAF test module. Figure 1 In Figure (b), the design of the welding hole connecting all the inner - layer metal copper has the problem that the heat dissipation of the welding hole to the inner layer is too fast during welding. This leads to the inability to solder on the welding hole position during the welding of the circuit, and multiple weldings are required, resulting in flux contamination and affecting the accuracy of the CAF test. Summary of the Utility Model
[0004] The present utility model provides a test module for conductive anode filaments. For the CAF test of hole - to - copper, the corresponding module design is optimized to reduce the welding difficulty, and at the same time, it does not occupy too much space, avoids flux contamination caused by multiple repeated weldings, and improves the accuracy of the CAF test.
[0005] In a first aspect, the present application provides a test module for conductive anode filaments, including a test area and a conductive area, and the conductive area is located on one side of the test area;
[0006] It includes a base layer, an inner layer, and a top layer stacked;
[0007] The inner layer of the test area includes multiple metal layers and insulating layers alternately arranged; the inner layer of the conductive area includes multiple insulating layers;
[0008] Each metal layer includes multiple metal sheets, and the metal sheets extend along a first direction;
[0009] It further includes a plurality of test channels; each test channel includes a plurality of test holes, a first welding hole, and a second welding hole; the test holes penetrate through the film layer of the test area; both the first welding hole and the second welding hole penetrate through the conductive area;
[0010] The metal sheet is electrically connected to the first welding hole through an inner-layer conductive wire; alternatively, there is an insulating layer between the metal sheet and the first welding hole, and the metal sheet and the first welding hole are electrically connected through a base-layer conductive wire;
[0011] In the same test channel, the test hole is electrically connected to the second welding hole, the first welding hole is connected to a first detection end; the second welding hole is connected to a second detection end; the potentials of the first detection end and the second detection end are different.
[0012] Optionally, each metal layer further includes a conductive ring, and the conductive rings in multiple metal layers are coaxial and electrically connected;
[0013] In the same metal layer, the first welding hole is located inside the conductive ring, and the metal sheet and the conductive ring are electrically connected through the inner-layer conductive wire.
[0014] Optionally, the test channel further includes a connection hole, the electrical connection hole penetrates through the test area and the end of the metal sheet close to the first welding hole; the electrical connection holes in multiple metal sheets are coaxial and electrically connected;
[0015] In the same test channel, the electrical connection hole is electrically connected to the first welding hole through a base-layer conductive wire on the surface of the base layer.
[0016] Optionally, the base-layer conductive wire is located on the base layer; or the base-layer conductive wire is an external metal wire.
[0017] Optionally, the metal sheet includes a plurality of hole rings;
[0018] In the same test hole, the center of the hole ring is coaxial with the center of the test hole, and the diameter of the test hole is smaller than the diameter of the hole ring.
[0019] Optionally, in the same metal layer,
[0020] In the same test channel, the difference in diameter between the test hole and the hole ring is the same;
[0021] In different test channels, the difference in diameter between the test hole and the hole ring is different.
[0022] Optionally, the plurality of test channels are arranged along a second direction; the diameters of all the test holes are the same;
[0023] In the same metal layer, along the first direction, the diameters of the hole rings in each metal sheet are the same; along the second direction, the diameters of the hole rings in multiple metal sheets are different or are set to gradually change; the first direction and the second direction are orthogonal and parallel to the plane where the metal layer is located.
[0024] Optionally, on the top layer, the test holes in the same test channel are electrically connected in sequence along the first direction and then are electrically connected to the second welding hole through the top layer conductive wire.
[0025] Optionally, the first detection end or the second detection end is grounded.
[0026] Optionally, an insulating layer is provided between the test hole, the first welding hole, and the second welding hole.
[0027] In summary, for the test module of the conductive anode filament provided in this application, by optimizing the inner layer design of the welding holes of the test module, the metal area between the test holes and the welding holes is reduced, the heat dissipation to the inner layer during the welding of the test holes is reduced, the flux contamination caused by repeated welding is avoided, the heat dissipation to the inner layer during welding can be reduced, the welding difficulty can be lowered, the accuracy of the CAF test can be improved. At the same time, this design is not affected by factors such as the drilling hole diameter, the number of printed board layers, and the printed board thickness, and can be applied to the CAF resistance test design of hole-to-wire in various situations. Description of the Drawings
[0028] Figure 1 is a schematic diagram of a test module of a conductive anode filament provided by the prior art;
[0029] Figure 2 is a schematic diagram of a test module of a conductive anode filament provided by this application;
[0030] Figure 3 is a schematic diagram of another test module of a conductive anode filament provided by this application;
[0031] Figure 4 is Figure 2 a cross-sectional schematic diagram of the test module of the conductive anode filament along the aa' direction in
[0032] Among them, the description of the drawings is as follows:
[0033] A - Test area; B - Conductive area; 10 - Base layer; 20 - Inner layer; 30 - Top layer; 21 - Metal layer; 22 - Insulating layer; 23 - Inner layer conductive wire; 24 - Top layer conductive wire; 25 - Conductive ring; 210 - Metal sheet; 211 - Hole ring; C - Test channel; 11 - Test hole; 12 - First welding hole; 13 - Second welding hole; 14 - Electrical connection hole; 41 - Base layer conductive wire; PV1 - First detection end connection; PV2 - Second detection end. Detailed implementation manners
[0034] The present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present application, rather than limiting the present application. Additionally, it should be noted that for the convenience of description, only the parts related to the present application rather than all the structures are shown in the drawings. Without departing from the spirit or scope of the present application, various modifications and changes can be made in the present application, which are obvious to those skilled in the art. Therefore, the present application is intended to cover the modifications and changes of the present application that fall within the scope of the corresponding claims (the claimed technical solutions) and their equivalents. It should be noted that the implementation manners provided in the embodiments of the present application can be combined with each other without conflict.
[0035] Among them, CAF failure refers to the fact that the insulating material in the PCB gradually forms a conductive channel under the influence of environmental factors such as electric field, temperature, and humidity, resulting in circuit short - circuit or abnormality. This failure mode poses a serious threat to the stability and safety of the product. The CAF resistance test is related to the reliability of the PCB product and the continuous stable operation time after the end - user components are installed. The CAF resistance test from hole to line is related to the hole - to - line design of the PCB. The stronger the CAF resistance from hole to line, the higher the wiring density of the PCB.
[0036] Based on this, in view of one or more of the above - mentioned problems in the prior art, the present utility model provides a test module for conductive anode filaments. Figure 2 is a schematic diagram of a test module for conductive anode filaments provided by the present application; Figure 3 is a schematic diagram of another test module for conductive anode filaments provided by the present application;
[0037] Figure 4 is Figure 2 a cross - sectional schematic diagram of the test module for conductive anode filaments along the aa' direction in. Refer to Figures 2 - 4 As shown, a test module for conductive anode filaments provided by an embodiment of the present application includes a test area A and a conductive area B. The conductive area B is located on one side of the test area A. The test module includes a base layer 10, an inner layer 20, and a top layer 30 which are stacked. The inner layer 20 of the test area A includes multiple metal layers 21 and insulating layers 22 that are alternately arranged. The inner layer 20 of the conductive area B includes multiple insulating layers 22. Each metal layer 21 includes multiple metal sheets 210, and the metal sheets 210 extend along the first direction (shown as the X direction in the figure). The test module further includes multiple test channels C. The test channels C include multiple test holes 11, a first welding hole 12, and a second welding hole 13. The test holes 11 penetrate through the film layer of the test area A. Both the first welding hole 12 and the second welding hole 13 penetrate through the conductive area B; As Figure 2As shown, the metal sheet 210 is electrically connected to the first welding hole 12 through the inner conductive wire 23; or, as Figure 3 shown, there is an insulating layer 22 between the metal sheet 210 and the first welding hole 12, and the metal sheet 210 is electrically connected to the first welding hole 12 through the base layer conductive wire 41; in the same test channel C, the test hole 11 is electrically connected to the second welding hole 13, the first welding hole 12 is connected to the first detection end PV1; the second welding hole 13 is connected to the second detection end PV2; the potentials of the first detection end PV1 and the second detection end PV2 are different.
[0038] Among them, Figure 2 in Figure (a), Figure 3 Figure (a) is a schematic diagram of the top layer of the CAF test module, Figure 2 in Figure (b) and Figure 3 Figure (b) is a schematic diagram of any metal layer in the inner layer of the CAF test module; Figure 2 in Figure (c) and Figure 3 Figure (c) is a schematic diagram of the base layer of the CAF test module.
[0039] The embodiment of the present application is directed to the CAF resistance test of the PCB. In some embodiments, to reduce the wiring difficulty and avoid the flux contamination caused by repeated soldering, the connection structure of the surface layer 30 of the CAF test module remains unchanged, and the structures of the inner layer 20 and the bottom layer 10 are designed.
[0040] Specifically, referring to Figures 2 - 4 shown, according to the film layer division of the CAF test module, the CAF test module is composed of a stacked base layer 10, inner layer 20, and top layer 30. Among them, the base layer 10 and the top layer 30 can cover the entire surface of the insulating material, playing a role of encapsulation and protection; the inner layer 20 is composed of multiple alternately arranged metal layers 21 and insulating layers 22, and the metal layer 21 is usually metal copper, for example, a copper sheet.
[0041] Referring to Figure 2 and Figure 3 shown, the whole of the CAF test module can be further divided into a test area A and a conductive area B. Among them, the test area A is a full substrate layer, and the conductive area B is located on one side of the test area A. The inner layer 20 of the test area A is composed of multiple alternately arranged metal layers 21 and insulating layers 22, and the inner layer 20 of the conductive area B is only composed of multiple insulating layers 22. Each metal layer 21 in the inner layer 20 of the test area A includes multiple metal sheets 210, and the metal sheets 210 extend along the X direction in the figure and are arranged along the Y direction in the figure. Among them, the metal sheets 210 in each metal layer 21 are insulated from each other. Among them, the first direction X and the second direction Y are orthogonal.
[0042] The test module further includes a plurality of test channels C, and each test channel C is composed of a plurality of test holes 11 arranged in the X direction in the figure, a first welding hole 12, and a second welding hole 13. The plurality of test channels C are arranged in the same manner as the metal sheets 210 in the Y direction in the figure. The test holes 11 penetrate through the top layer 30 of the test area A, the multi-layer alternately arranged metal layers 21 and insulating layers 22 of the inner layer 20, and the base layer 10, and at the same time penetrate through the hole rings of the metal sheets 210 in each metal layer 21 of the test area A; both the first welding hole 12 and the second welding hole 13 penetrate through the top layer 30, the insulating layer 22, and the base layer 10 of the conductive area B.
[0043] Regarding the film layers of the inner layer 20 penetrated by the first welding hole 12 and the second welding hole 13 in the conductive area B:
[0044] A feasible implementation manner, as shown in Figure 2 Figure (b) therein, can reduce the area of the metal (large copper foil) below the welding positions of the first welding hole 12 and the second welding hole 13 in the inner layer 20. The metal sheet 210 and the first welding hole 12 are electrically connected by the inner layer conductive wire 23 to achieve the electrical connection between the metal sheet 210 and the first welding hole 12; a feasible implementation manner, as shown in Figure 2 Figure (b) therein, can completely hollow out the metal (large copper foil) below the welding positions of the first welding hole 12 and the second welding hole 13 in the inner layer 20, so that there is only the insulating layer 22 between the metal sheet 210 and the first welding hole 12, and the metal sheet 210 and the first welding hole 12 are electrically connected by the base layer conductive wire 41.
[0045] By adopting the above embodiments, the metal connection area between the test hole 11 and the first welding hole 12 and the second welding hole 13 can be reduced, and the heat dissipation from the test hole 11 to the first welding hole 12 and the second welding hole 13 in the inner layer 20 during welding can be reduced, which is beneficial to increasing the success rate of one-time welding, reducing the wiring difficulty, and avoiding the problem of flux contamination caused by repeated welding.
[0046] Referring to Figure 2 and Figure 3 Figure (a) therein, in the same test channel C, the test hole 11 and the first welding hole 12 are electrically connected by the top layer conductive wire 24 in the top layer 30; referring to Figure 2 and Figure 3As shown in Figure (c), the first welding hole 12 is connected to the first detection end PV1; the second welding hole 13 is connected to the second detection end PV2. When performing the CAF resistance test on a test channel C, a test circuit is formed by the second detection end PV2 - the second welding hole 13 - multiple test holes 11 - the first welding hole 12 - the first detection end PV1. The first detection end PV1 provides a first test voltage to the first welding hole 12, and the second detection end PV2 provides a second test voltage to the second welding hole 13. There is a voltage difference between the first test voltage and the second test voltage, realizing the CAF resistance test of the PCB.
[0047] Among them, Figure 2 Figure (c) and Figure 3 Figure (c) only shows the connection schematic diagram of the first welding hole 12 and the first detection end PV1, the second welding hole 13 and the second detection end PV2 in a group of test channels C. More electrical connections are not shown one by one here.
[0048] In summary, the test module for conductive anode filaments provided by this application optimizes the inner layer design of the welding holes of the test module, reduces the metal area between the test holes and the welding holes, which is beneficial to reducing the heat dissipation to the inner layer during the welding of the test holes, avoiding the flux contamination caused by repeated welding, reducing the welding difficulty, improving the accuracy of the CAF test. At the same time, this design is not affected by the drilling hole diameter, the number of printed circuit board layers, the thickness of the printed circuit board, etc., and can be applied to the CAF resistance test design of hole-to-line in various situations.
[0049] On the basis of the above embodiments, referring to Figure 2 and Figure 4 shown, each metal layer 21 further includes a conductive ring 25. The conductive rings 25 in the multi-layer metal layers 21 are coaxial and electrically connected; in the same metal layer 21, the first welding hole 12 is located inside the conductive ring 25, and the metal sheet 210 is electrically connected to the conductive ring 25 through the inner layer conductive wire 23.
[0050] Specifically, referring to Figure 2 and Figure 4 shown, a conductive ring 25 is arranged around the first welding hole 12. The conductive rings 25 of each layer are electrically connected along the Z direction in the figure, so that the electrical connection between the first welding hole 12 and the metal sheet 210 in the inner layer 20 realizes the first welding hole 12 providing the first test voltage to the conductive ring 25 of each layer, and further realizes the CAF resistance test of the test channel C.
[0051] On the basis of the above embodiments, referring to Figure 3As shown, the test channel C further includes electrical connection holes 14. The electrical connection holes 14 penetrate through the test area A and also penetrate through one end of the metal sheet 210 close to the first welding hole 12. The electrical connection holes 14 in the multi-layer metal sheet 210 are coaxial and electrically connected. In the same test channel C, the electrical connection holes 14 are electrically connected to the first welding hole 12 through the base layer conductive wire 41 on the surface of the base layer 10.
[0052] Specifically, referring to Figure 3 As shown, by completely hollowing out the metal (large copper sheet) below the welding positions of the first welding hole 12 and the second welding hole 13 in the inner layer 20, an electrical connection hole 14 is added to one end surface of the metal sheet 210 close to the first welding hole 12. This hole replaces the first welding hole 12 to achieve conduction with all the inner layer metal sheets 210, realizing full conduction of all the inner layers 20. Further, through the base layer conductive wire 41 on the surface of the base layer 10, electrical connection between the electrical connection hole 14 and the first welding hole 12 is achieved. Here, the diameter size, position, etc. of the electrical connection hole 14 are not restricted, Figure 3 merely as an example.
[0053] When performing a CAF resistance test on a test channel C, the second detection end PV2 - the second welding hole 13 - multiple test holes 11 - the electrical connection hole 14 - the first welding hole 12 - the first detection end PV1 form a test circuit. The first detection end PV1 provides a first test voltage to the first welding hole 12, and the second detection end PV2 provides a second test voltage to the second welding hole 13. There is a voltage difference between the first test voltage and the second test voltage, realizing the CAF resistance test of the test channel C.
[0054] As an example, as Figure 3 shown, by controlling the electrical connection hole 14 to have a smaller size, it is only necessary to make the electrical connection holes 14 in the multi-layer metal sheet 210 coaxial and electrically connected, reducing the area of the metal sheet 210 close to the first welding hole 12 and reducing the heat dissipation to the inner layer during welding.
[0055] Optionally, referring to Figure 3 the figure (c) in
[0056] shown, the base layer conductive wire 41 is located on the base layer 10; or, the base layer conductive wire 41 is an external metal wire.
[0057] Based on the above embodiments, referring to Figures 2 - 4As shown, the metal sheet 210 includes a plurality of hole rings 211, and the insulating layer 22 includes test holes 11; in the same test hole 11, the center of the hole ring 211 is coaxial with the center of the test hole 11, and the diameter D1 of the test hole 11 is smaller than the diameter D2 of the hole ring 211.
[0058] Specifically, referring to Figures 2 - 4 As shown, along the Z direction in the figure, the centers of the hole rings 211 in the multi-layer metal sheet 210 and the test holes 11 in the multi-layer insulating layer 22 are coaxial. The hole ring 211 is electrically connected to the first welding hole 12, and the test hole 11 is electrically connected to the second welding hole 13. In this way, a voltage difference is formed between the hole ring 211 and the test hole 11; in the XY plane of the figure, the diameter D1 of the test hole 11 is smaller than the diameter D2 of the hole ring 211, that is, the test hole 11 is nested within the hole ring 211. Such a setting can insulate the hole ring 211 and the test hole 11 electrically, so that the CAF resistance performance of the printed circuit board can be tested.
[0059] Based on the above embodiments, referring to Figures 2 - 4 As shown, in the same metal layer 21 and the same test channel C, the diameter difference between the test hole 11 and the hole ring 211 is the same; in different test channels C, the diameter differences between the test hole 11 and the hole ring 211 are different.
[0060] Exemplarily, referring to Figures 2 - 4 As shown, along the Y direction in the figure, in the same test channel C, the diameter difference between the corresponding test hole 11 and the hole ring 211 of the same test hole 11 remains consistent; in different test channels C, the diameter differences between the corresponding test holes 11 and the hole ring 211 of different rows of test holes 11 are different. In this way, differential detection with different differences can be carried out to determine the minimum difference for the printed circuit board to pass the CAF test, providing the minimum hole-to-line distance for the printed circuit board design, that is, the minimum difference for passing the CAF test.
[0061] Based on the above embodiments, continue to refer to Figure 2 As shown, a plurality of test channels C are arranged along the second direction Y; the diameters of the test holes 11 are the same; in the same metal layer 21, along the first direction X, the diameters of the hole rings 211 in each metal sheet 210 are the same; along the second direction Y, the diameters of the hole rings 211 in the plurality of metal sheets 210 are different or are set to be gradually variable.
[0062] Exemplarily, referring to Figure 2 、 Figure 3 As shown, the diameters of all the test holes 11 are set to be the same, and by changing the diameters of the hole rings 211 in different rows, the change in the diameter difference between the test hole 11 and the hole ring 211 is realized.
[0063] For example, in combination with Figure 2In Figure (a), from top to bottom, the diameter differences between the test holes 11 and the hole rings 211 are set to be 10 mil, 9 mil, 8 mil, 7 mil, 6 mil, and 5 mil in sequence.
[0064] Among them, mil: mil, which is one thousandth of an inch.
[0065] Based on the above embodiments, continue to refer to Figure 2 Figure (a) in Figure 3 As shown in Figure (a), on the top layer 30, the test holes 11 in the same test channel C are electrically connected in sequence along the first direction X and then electrically connected to the second welding hole 13 through the top layer conductive wire 24.
[0066] Optionally, the first detection end PV1 or the second detection end PV2 is grounded to GND.
[0067] Specifically, when the first detection end PV1 is grounded to GND, the second detection end PV2 is connected to the power supply; when the second detection end PV2 is grounded to GND, the first detection end PV1 is connected to the power supply.
[0068] Based on the above embodiments, continue to refer to Figure 2 and Figure 3 As shown, an insulating material, that is, the insulating layer 22, is filled between the test hole 11, the first welding hole 12, and the second welding hole 13.
[0069] Among them, in the embodiments of the present application, the test module of the conductive anode wire can also be adjusted by adjusting the tool selection for drilling, the width of the inner layer metal sheet (copper foil), the distance from the hole wall to the inner layer wire, the number of holes, and the test specifications from the hole to the wire.
[0070] The test module provided by the above embodiments can reduce the heat diffusion area from the welding hole to the inner layer test hole, reduce the heat dissipation from the test hole to the inner layer during welding, reduce the temperature loss of the molten tin during welding, avoid the phenomenon of "not eating tin" caused by too fast temperature loss of the molten tin, improve the success rate of one-time welding, avoid multiple rework weldings, and avoid the CAF failure phenomenon caused by the contamination of the flux.
[0071] The test module provided by the above embodiments has the following advantages in the conductive anode filament (CAF) test of the PCB:
[0072] 1. It can reduce the welding difficulty of the hole-to-wire CAF test module and make the welding during CAF testing easier.
[0073] 2. It is beneficial to reduce false soldering, make the solder joints more firm, and improve the welding reliability.
[0074] 3. It can improve the success rate of one-time welding, reduce repeated welding, and avoid the flux contamination caused by multiple weldings.
[0075] 4. The cost is relatively low, which can avoid occupying a large area and meet the CAF test requirements in a small space.
[0076] 5. The test spacing and the number of test holes can be changed according to needs, with great flexibility, and can be implemented in PCB products with any layer thickness.
[0077] Note that the above is only the preferred embodiment of the present utility model and the applied technical principles. Those skilled in the art will understand that the present utility model is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments, combinations with each other, and substitutions can be made by those skilled in the art without departing from the protection scope of the present utility model. Therefore, although the present utility model has been described in detail through the above embodiments, the present utility model is not limited to the above embodiments. Without departing from the concept of the present utility model, more other equivalent embodiments can be included, and the scope of the present utility model is determined by the scope of the appended claims.
Claims
1. A test module for a conductive anode wire, characterized in that: It includes a test area and a conductive area, wherein the conductive area is located on one side of the test area; Includes base layer, inner layer and top layer in a layered arrangement: The inner layer of the test area includes multiple layers of metal layers and insulating layers arranged alternately; the inner layer of the conductive area includes multiple layers of insulating layers; Each of the metal layers comprises a plurality of metal sheets, and the metal sheets extend along a first direction; It also includes a plurality of test channels; the test channels include a plurality of test holes, a first welding hole and a second welding hole; the test holes penetrate the film layer of the test area; the first welding hole and the second welding hole both penetrate the conductive area; The metal sheet is electrically connected to the first welding hole through an inner layer conductive wire; or, an insulating layer is provided between the metal sheet and the first welding hole, and the metal sheet is electrically connected to the first welding hole through a base layer conductive wire; In the same test channel, the test hole is electrically connected to the second welding hole, the first welding hole is connected to the first detection end; the second welding hole is connected to the second detection end; the first detection end and the second detection end have different potentials.
2. The test module according to claim 1, characterized in that: Each of the metal layers further comprises a conductive ring, and the conductive rings in the multiple metal layers are coaxial and electrically connected; In the same metal layer, the first welding hole is located in the conductive ring, and the metal sheet is electrically connected to the conductive ring through the inner layer conductive wire.
3. The test module according to claim 1, characterized in that: The test channel further comprises an electrical connection hole, the electrical connection hole passes through the test area and passes through one end of the metal sheet close to the first welding hole; the electrical connection holes in the multiple layers of the metal sheet are coaxial and electrically connected; In the same test channel, the electrical connection hole is electrically connected to the first welding hole on the surface of the base layer through the base layer conductive wire.
4. The test module according to claim 3, characterized in that: The base layer conductive wire is located on the base layer; or, the base layer conductive wire is an external metal wire.
5. The test module according to claim 1, characterized in that: The metal sheet includes a plurality of hole rings; In the same test hole, the center of the hole ring is coaxial with the center of the test hole, and the diameter of the test hole is smaller than the diameter of the hole ring.
6. The test module according to claim 5, characterized in that: In the same metal layer, In the same test channel, the diameter difference between the test hole and the hole ring is the same; In different test channels, the diameter difference between the test hole and the hole ring is different.
7. The test module according to claim 6, characterized in that: The plurality of test channels are arranged along the second direction; the diameters of all the test holes are the same; In the same metal layer, along the first direction, the diameters of the hole rings in each of the metal sheets are the same; Along the second direction, the diameters of the hole rings in the plurality of metal sheets are different or gradually arranged; the first direction and the second direction are orthogonal and parallel to the plane where the metal layer is located.
8. The test module according to claim 1, characterized in that: On the top layer, the test holes in the same test channel are electrically connected in sequence along the first direction and then electrically connected to the second welding holes through the top layer conductive wires.
9. The test module according to claim 1, characterized in that: The first detection end or the second detection end is grounded.
10. The test module according to claim 1, characterized in that: An insulating layer is provided between the test hole, the first welding hole and the second welding hole.