A device and method for testing electrochemical properties of intermetallic compounds

Abstract

The present invention relates to an intermetallic compound electrochemical performance testing device and method, belonging to the field of electrochemical performance testing of micron-sized metals, the device comprising: a Kelvin probe, used to determine a target area to be tested of the intermetallic compound to be tested; and an electrochemical test pen, fixed on the Kelvin probe, used to test the target area to be tested of the intermetallic compound to be tested along the motion trajectory of the Kelvin probe to obtain the electrochemical performance of the intermetallic compound to be tested; wherein the spacing between the electrochemical test pen and the Kelvin probe is not less than the distance between the electrochemical test pen and the Kelvin probe that does not interfere with each other. In this way, based on the test device composed of the Kelvin probe and the electrochemical test pen fixed on the Kelvin probe and used to test along the motion trajectory of the Kelvin probe, its manufacturing process requirements are relatively simple, the experimental cost is low, and the electrochemical performance test of intermetallic compounds as small as 2μm in diameter can be achieved.

Description

Technical Field

[0001] The invention relates to the field of electrochemical performance testing of micron-sized metals, and in particular to a device and method for testing the electrochemical performance of intermetallic compounds. Background Art

[0002] With the continuous development of micro-area electrochemical methods, micron-scale electrochemical tests have also begun to emerge, mainly divided into two categories: scanning microprobe technology (SMPT) and microcapillary technology (MCT). Although SMPT technology can provide data such as local electrochemical potential, local current distribution, local impedance response, Volta potential, etc. on the corrosion surface, this type of technology is limited by the use environment and cannot directly obtain electrochemical kinetic information in the local area. MCT technology has been used to perform electrochemical measurements on tiny areas at the micron to millimeter scale, and the test diameter is usually as small as 50m. Although this technology solves the problem of electrochemical measurement in small areas at the micron level, it also has some defects, such as: difficulty in making and operating microcapillaries, high ohmic resistance, electrolyte leakage, capillary blockage, and too large a test diameter.

[0003] To address the above issues, the photolithography mask technology in the semiconductor field was introduced into micro-area electrochemical testing. Although this technology can achieve a minimum resolution of 2μm, the photolithography mask needs to meet strict operating environment requirements and the experimental cost is high, which to some extent limits the promotion and use of this technology. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide an intermetallic compound electrochemical performance testing device and method, which are used to completely or at least partially solve the technical problems existing in the above-mentioned prior art.

[0005] In order to achieve the above object, an embodiment of the present invention provides a testing device for testing the electrochemical properties of an intermetallic compound, comprising:

[0006] Kelvin probe for determining the target area of ​​the intermetallic compound to be detected; and

[0007] An electrochemical test pen is fixed on the Kelvin probe and is used to test the target area of ​​the intermetallic compound to be tested along the movement trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested; wherein the spacing between the electrochemical test pen and the Kelvin probe is not less than a distance at which the electrochemical test pen and the Kelvin probe do not interfere with each other.

[0008] Optionally, the testing device also includes a multi-through-hole array plate attached to the surface of the intermetallic compound to be tested, which is used to enable the Kelvin probe to scan the through-hole array plate to determine the through-hole array coordinates, and then enable the electrochemical test pen to click on the target area to be tested along the through-hole array coordinates to obtain the electrochemical properties of the intermetallic compound to be tested.

[0009] Optionally, the electrochemical test pen comprises a reference electrode, a counter electrode and a sponge storing an electrolyte solution, wherein the reference electrode and the counter electrode are immersed in the sponge storing an electrolyte solution;

[0010] The sponge storing the electrolyte solution is connected to the pen tip of the electrochemical test pen.

[0011] Optionally, the reference electrode is an Ag / AgCl reference electrode; and the counter electrode is a Pt wire.

[0012] Optionally, the horizontal offset between the tip of the electrochemical test pen and the Kelvin probe does not exceed a preset offset threshold, so that the tip of the electrochemical test pen reaches the target area to be tested according to the movement trajectory of the Kelvin probe.

[0013] Optionally, the pen tip of the electrochemical test pen is a pen tip made of a porous diaphragm material.

[0014] Optionally, the pore diameter of the porous membrane material pen tip ranges from 10 to 20 microns.

[0015] Optionally, the testing device further comprises a macro control console for controlling the operation of the Kelvin probe.

[0016] Optionally, the moving step length of the macro control console does not exceed the diameter of the target area to be measured.

[0017] On the other hand, an embodiment of the present invention further provides a method for testing the electrochemical properties of an intermetallic compound, the method comprising:

[0018] Determine the target area of ​​the intermetallic compound to be detected based on the Kelvin probe;

[0019] The electrochemical test pen fixed on the Kelvin probe is controlled to test the target area of ​​the intermetallic compound to be tested along the motion trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested; wherein the spacing between the electrochemical test pen and the Kelvin probe is not less than the distance between the electrochemical test pen and the Kelvin probe that does not interfere with each other.

[0020] Through the above technical scheme, based on a testing device consisting of a Kelvin probe for determining a target area to be tested of an intermetallic compound to be tested; and an electrochemical test pen fixed on the Kelvin probe and used to test the target area to be tested of the intermetallic compound to be tested along the motion trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested, the manufacturing process requirements are relatively simple, the experimental cost is low, and the electrochemical performance test of intermetallic compounds in an area as small as 2μm in diameter can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to better demonstrate the specific implementation details of the present invention, the important steps in the embodiments will be illustrated and introduced below. It should be understood that the following drawings only illustrate the embodiments of the present invention, but are not limited to other scopes.

[0022] Figure 1 A schematic diagram of the structure of an intermetallic compound electrochemical performance testing device provided by an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of the structure of an electrochemical test pen provided by an embodiment of the present invention;

[0024] Figure 3 A schematic diagram of the horizontal offset between the tip of an electrochemical test pen and a Kelvin probe provided by an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of a polyimide film micrometer-scale circular through hole array provided in an embodiment of the present invention;

[0026] Figure 5 A schematic diagram of placing a metal specimen with a polyimide film attached thereto under a Kelvin probe provided in an embodiment of the present invention;

[0027] Figure 6 The present invention provides an implementation flow chart of a method for testing the electrochemical properties of intermetallic compounds according to an embodiment of the present invention.

[0028] Description of Reference Numerals

[0029] 10 Kelvin probe 110 reference electrode

[0030] 111 pairs of electrodes 112 sponge storing electrolyte solution

[0031] 11Electrochemical test pen 12Intermetallic compound

[0032] 13 Macro console DETAILED DESCRIPTION

[0033] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0034] See also Figure 1 FIG. 1 is a schematic diagram of a structure of an intermetallic compound electrochemical performance testing device provided by an embodiment of the present invention, comprising:

[0035] A Kelvin probe 10 is used to determine a target region of the intermetallic compound to be detected; and

[0036] The electrochemical test pen 11 is fixed on the Kelvin probe 10 and is used to test the target area of ​​the intermetallic compound 12 to be tested along the movement trajectory of the Kelvin probe 10 to obtain the electrochemical properties of the intermetallic compound 12 to be tested; wherein the spacing between the electrochemical test pen 11 and the Kelvin probe 10 is not less than the distance between the electrochemical test pen 11 and the Kelvin probe 10 that does not interfere with each other.

[0037] It should be understood that the distance between the electrochemical test pen 11 and the Kelvin probe 10 at which they do not interfere with each other can be set according to specific application scenarios, for example, 30 mm, which is not limited here.

[0038] In some embodiments, the electrochemical test pen 11 is fixed on the Kelvin probe 10 using a robotic arm.

[0039] Preferably, in this embodiment, the diameter of the Kelvin probe is selected to be 10 μm.

[0040] In some embodiments, the testing device also includes a multi-through-hole array plate, which is placed on the surface of the intermetallic compound 12 to be tested, and is used to enable the Kelvin probe 10 to scan the through-hole array plate to determine the through-hole array coordinates, and then enable the electrochemical test pen 11 to click on the target area to be tested along the through-hole array coordinates to obtain the electrochemical properties of the intermetallic compound to be tested.

[0041] In some embodiments, the Kelvin probe 10 is driven by a macro control console, and the stepping movement accuracy in the xyz direction is set to 1 μm. The surface distance between the Kelvin probe and the intermetallic compound 12 to be tested is adjusted to about 100±10 μm. The vibration frequency of the Kelvin probe is set to 80 Hz, and the amplitude is 30 μm. A stepping surface scanning method is used to record the lattice coordinates of each through hole relative to the test starting point to determine the target area to be tested of the intermetallic compound to be tested.

[0042] In some embodiments, see Figure 2, which is a schematic diagram of the structure of an electrochemical test pen provided by an embodiment of the present invention, includes: a reference electrode 110, a counter electrode 111 and a sponge 112 storing an electrolyte solution.

[0043] In some embodiments, see Figure 2 As shown, the reference electrode 110 and the counter electrode 111 are immersed in the sponge 112 storing the electrolyte solution; the sponge 112 storing the electrolyte solution is connected to the tip of the electrochemical test pen 11, thus forming a three-electrode system.

[0044] Preferably, the reference electrode is an Ag / AgCl reference electrode; the counter electrode is a Pt wire, the tip of the electrochemical test pen is a porous diaphragm material tip, and the pore diameter of the porous diaphragm material tip ranges from 10 to 20 microns.

[0045] It should be noted that the pen tip of the electrochemical test pen 11 is a porous diaphragm material, and its pore size can be adjusted accordingly in combination with the type of electrolyte solution. In this embodiment, the pore sizes of the pen tip are set to 10-20 μm. In this way, it can ensure that the electrolyte solution in the sponge 112 can reach the surface of the sample to be tested (i.e., the intermetallic compound to be tested) through the porous pen tip, and can also ensure that the electrolyte solution does not overflow under the action of surface tension.

[0046] In some embodiments, see Figure 3 As shown, the horizontal offset between the tip of the electrochemical test pen 11 and the Kelvin probe 10 does not exceed the preset offset threshold d, so that the tip of the electrochemical test pen 11 reaches the target area to be tested according to the movement trajectory of the Kelvin probe 10 (or the positioning sequence of the Kelvin probe 10).

[0047] It should be understood that the preset offset threshold d can be set according to the actual application scenario, and generally does not exceed the radius of the pen tip, and is not limited here.

[0048] In some embodiments, see Figure 1 As shown, the testing device further includes a macro control console 13 for controlling the operation of the Kelvin probe.

[0049] In some embodiments, a macro console 13 is used to fix the Kelvin probe 10. The macro console 13 can be driven by a stepper motor so that its stepping movement accuracy in the xyz direction is 1 μm. Before the test, the distance between the Kelvin probe 10 and the surface of the intermetallic compound 12 to be tested is adjusted to be approximately 100±10 μm, and the vibration frequency of the Kelvin probe 10 is set to 80 Hz and the amplitude is 30 μm.

[0050] In some embodiments, the moving step length of the macro control console 13 does not exceed the diameter of the target area to be measured. For example, if the diameter of the target area to be measured is 10 μm, the moving step length of the robot arm 13 does not exceed 10 μm.

[0051] In this way, the testing device is composed of a Kelvin probe for determining the target area to be tested of the intermetallic compound to be tested; and an electrochemical test pen fixed on the Kelvin probe and used to test the target area to be tested of the intermetallic compound to be tested along the movement trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested. The manufacturing process requirements are relatively simple and the experimental cost is low. The electrochemical performance test of intermetallic compounds in an area as small as 2μm in diameter can be realized.

[0052] In some embodiments, when the testing device in any of the above embodiments is used to test the electrochemical properties of the intermetallic compound to be tested, the following steps can be performed:

[0053] Step 1: wire cut the sample (i.e., the intermetallic compound to be tested) and embed the sample using conductive hot embedding powder.

[0054] In some embodiments, the metal specimen (ie, the intermetallic compound to be tested) is cut into a 10 mm×10 mm×3 mm square, and the specimen is inlaid using conductive hot-mounting powder, and the diameter of the inlaid specimen is 30 mm.

[0055] Step 2: After mechanical polishing, the sample is placed under a scanning electron microscope and combined with an energy dispersive spectrometer (EDS) to preliminarily determine the size of the intermetallic compound.

[0056] Step 3: Select the appropriate spot size based on the size of the intermetallic compound, and use a cold source laser to drill holes in the polyimide film to obtain a micron-scale circular through-hole array.

[0057] Step 4: Attach the polyimide film to the surface of the sample to be tested.

[0058] Step 5: Place the sample to be tested under the scanning electron microscope again, and use the energy dispersive spectrometer (EDS) to determine the composition of the area to be tested in each circular through hole array region and mark the through hole lattice coordinates.

[0059] In some embodiments, a polyimide film with adhesive backing (15-25 μm thick) is used to obtain a micrometer-scale circular through hole array (such as Figure 4The selection of through-hole size is generally based on the size of the intermetallic compound on the metal surface. A thin film containing small holes is attached to the surface of the metal specimen to obtain an array of micron-scale metal exposure areas. The metal specimen is placed under a scanning electron microscope (SEM) for observation, and an energy dispersive spectrometer (EDS) is used to determine the composition of the area to be tested in each small hole area and mark the through-hole lattice coordinates, thereby achieving precise control of the micron-scale metal area test area.

[0060] Step 6: Place the metal specimen with the polyimide film attached under the Kelvin probe and use the Kelvin probe to draw a Volta potential dot matrix diagram.

[0061] In some embodiments, see Figure 5 As shown, a schematic diagram of placing a metal specimen with a polyimide film attached under a Kelvin probe provided by an embodiment of the present invention is shown. A metal specimen 12 with a polyimide film attached is placed under a Kelvin probe 10, and the probe is fixed in the form of a macro console 13. The macro console 13 is driven by a stepper motor, and the stepping movement accuracy in the xyz direction is 1μm. The distance between the probe and the sample surface is adjusted to about 100±10μm, the vibration frequency is 80Hz, the amplitude is 30μm, and the moving step size of the macro console 13 does not exceed the diameter of the through hole of the polyimide film. For example, if the through hole size is 10μm, the step size does not exceed 10μm. The dot matrix coordinates of each through hole relative to the test starting point are recorded by using a stepping surface scanning method. Since the polyimide film has good insulation properties, the effective positioning accuracy of the Kelvin probe is the same as the movement accuracy in the xyz direction, which can reach 1μm.

[0062] Step 7: Fill the electrochemical test pen with electrolyte solution and fix the electrochemical test pen on the Kelvin probe in the form of a mechanical arm. It should be noted that the horizontal offset between the tip of the electrochemical test pen and the Kelvin probe does not exceed the radius of the tip.

[0063] Step 8: Determine the position of the target area to be tested by combining the Volta potential dot matrix diagram and the through-hole dot matrix coordinates marked by the scanning electron microscope, and press the tip of the electrochemical test pen into the through-hole of the polyimide film (i.e., the position of the target area to be tested).

[0064] Step 8: Set the test parameters according to the experimental requirements and conduct the test.

[0065] On the other hand, the present invention also provides a method for testing the electrochemical properties of intermetallic compounds. Figure 6 As shown, it is a flow chart of a method for testing the electrochemical properties of intermetallic compounds provided by an embodiment of the present invention, which specifically includes the following execution steps:

[0066] S600: Determine a target region of the intermetallic compound to be detected based on the Kelvin probe.

[0067] S601: controlling the electrochemical test pen fixed on the Kelvin probe to test the target area of ​​the intermetallic compound to be tested along the movement trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested.

[0068] Wherein, the distance between the electrochemical test pen and the Kelvin probe is not less than the distance between the electrochemical test pen and the Kelvin probe so as not to interfere with each other.

[0069] This article uses specific examples to further explain the purpose, principle and implementation plan of the invention. The description of the above embodiment is only used to help understand the present invention and is not used to limit the present embodiment. On the contrary, within the spirit and principle of the present invention, there are improvements, replacements, etc. in the specific implementation method and application scope, which are all within the scope of the present invention.

Claims

1. An intermetallic compound electrochemical performance testing device, characterized in that: include: Kelvin probe, used to determine the target area of ​​the intermetallic compound to be tested; as well as An electrochemical test pen, fixed on the Kelvin probe, is used to test the target area of ​​the intermetallic compound to be tested along the motion trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested; wherein the spacing between the electrochemical test pen and the Kelvin probe is not less than a distance between the electrochemical test pen and the Kelvin probe that does not interfere with each other; The testing device also includes a multi-through-hole array plate, which is placed on the surface of the intermetallic compound to be tested, and is used to enable the Kelvin probe to scan the through-hole array plate to determine the through-hole array coordinates, and then enable the electrochemical test pen to click the target area to be tested along the through-hole array coordinates to obtain the electrochemical properties of the intermetallic compound to be tested; The electrochemical test pen comprises a reference electrode, a counter electrode and a sponge storing an electrolyte solution; The reference electrode and the counter electrode are immersed in the sponge storing the electrolyte solution; The sponge storing the electrolyte solution is connected to the tip of the electrochemical test pen; The testing device further comprises a macro control console for controlling the operation of the Kelvin probe.

2. The testing device according to claim 1, characterized in that: The reference electrode is an Ag / AgCl reference electrode; The counter electrode is a Pt wire.

3. The testing device according to claim 1, characterized in that: The horizontal offset between the tip of the electrochemical test pen and the Kelvin probe does not exceed a preset offset threshold, so that the tip of the electrochemical test pen reaches the target area to be tested according to the motion trajectory of the Kelvin probe.

4. The testing device according to claim 1, characterized in that: The pen tip of the electrochemical test pen is a pen tip made of porous diaphragm material.

5. The testing device according to claim 4, characterized in that: The pore diameter of the porous membrane material pen tip ranges from 10 to 20 microns.

6. The testing device according to claim 1, characterized in that: The moving step length of the macro control console does not exceed the diameter of the target area to be measured.

7. A method for testing the electrochemical properties of intermetallic compounds, the method using the testing device according to any one of claims 1 to 6, characterized in that: The method includes: Determine the target area of ​​the intermetallic compound to be detected based on the Kelvin probe; The electrochemical test pen fixed on the Kelvin probe is controlled to test the target area of ​​the intermetallic compound to be tested along the motion trajectory of the Kelvin probe to obtain the electrochemical properties of the intermetallic compound to be tested; wherein the spacing between the electrochemical test pen and the Kelvin probe is not less than the distance between the electrochemical test pen and the Kelvin probe that does not interfere with each other.

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