Ion migration detection method

Abstract

The invention relates to the technical field of ion migration detection, in particular to an ion migration detection method which is used for ion migration detection of a conductor structure, and the conductor structure comprises a dielectric layer substrate, a first metal conductor and a second metal conductor. The first metal conductor and the second metal conductor are arranged on the dielectric layer substrate at an interval, and the method comprises the steps that the first metal conductor and the second metal conductor are connected with different electrodes of a direct-current power supply, and direct-current voltage is applied to the first metal conductor and the second metal conductor through the direct-current power supply; acquiring parameter change information of the first metal conductor and / or the second metal conductor; and when the parameter change information is within a set threshold range, the direct-current power supply stops applying the direct-current voltage. According to the method, ion migration detection is carried out through the direct-current voltage, the service life of the conductor structure can be effectively predicted, and the test method of applying the direct-current voltage can simulate actual use conditions and is more adaptive to the use scene of the current conductor structure.

Description

Technical Field

[0001] The present application relates to the technical field of ion migration detection, and in particular to an ion migration detection method. Background Art

[0002] The electromagnetic compatibility (EMC) of high-frequency differential signals, such as Universal Serial Bus (USB) and High Definition Multimedia Interface (HDMI), must be maintained to prevent electromagnetic interference to external devices and signal anomalies caused by external devices. Currently, filtering circuits composed of common-mode inductors are commonly used to prevent this.

[0003] The laminated common-mode inductor is a space common-mode inductor suitable for ultra-thin electronic products. The manufacturing process of the laminated common-mode inductor is to print silver ions on the electrodes through a printing process to form a coil. The two layers of coils are separated by a dielectric layer. The material of the dielectric layer is generally a non-conductive material containing components such as silicon dioxide / aluminum oxide.

[0004] However, due to ion migration, silver ions are prone to migration under long-term voltage, causing a short circuit between the upper and lower coils of the common-mode inductor, resulting in circuit malfunction and even product damage. To address this issue, a common approach is to develop dielectric layer materials that slow silver migration and thus extend the life of the common-mode inductor.

[0005] For common-mode inductors made of different dielectric materials, ion migration needs to be tested to determine their service life. Existing testing methods include applying an AC voltage to a single coil of the inductor, desoldering the inductor when the voltage reaches the test point, and then measuring the leakage current of the two coils to predict the lifespan of the inductor.

[0006] However, as the operating mode of high-frequency signals in electronic devices changes, ion migration may also occur between the dual coils of the common-mode inductor. Current testing methods cannot effectively test and thus cannot accurately determine the service life of the common-mode inductor. Summary of the Invention

[0007] In order to solve at least the above technical problems existing in the prior art, the present application provides an ion migration detection method.

[0008] On one hand, the present application provides an ion migration detection method for ion migration detection of a conductor structure, wherein the conductor structure includes a dielectric layer substrate, a first metal conductor, and a second metal conductor, wherein the first metal conductor and the second metal conductor are spaced apart on the dielectric layer substrate. The method includes: connecting the first metal conductor and the second metal conductor to different electrodes of a DC power supply, and applying a DC voltage to the first metal conductor and the second metal conductor via the DC power supply; obtaining parameter change information of the first metal conductor and / or the second metal conductor; and when the parameter change information is within a set threshold range, stopping the DC power supply from applying the DC voltage, thereby completing the detection.

[0009] In some embodiments, the first metal conductor includes a first coil, the second metal conductor includes a second coil, and the first coil and the second coil are isolated by the dielectric layer substrate; the first coil includes a first pin and a second pin, and the second coil includes a third pin and a fourth pin, the first pin is connected to the positive pole of the DC power supply, and the second pin and the third pin are respectively connected to the negative pole of the DC power supply.

[0010] In some embodiments, multiple groups of the conductor structures are included; multiple first pins are respectively connected to the positive electrode of the DC power supply, and multiple second pins and the third pins are respectively connected to the negative electrode of the DC power supply.

[0011] In some embodiments, the method for obtaining parameter change information of the first metal conductor and / or the second metal conductor includes: obtaining the parameter change information of the first coil and obtaining parameter change information between the first coil and the second coil.

[0012] In some embodiments, the parameter change information includes temperature change information and / or impedance value change information.

[0013] In some embodiments, the method for obtaining parameter change information of the first metal conductor and / or the second metal conductor includes: obtaining temperature change information of the first metal conductor and / or the second metal conductor by using a temperature imaging device.

[0014] In some embodiments, the method for obtaining the temperature change information of the first metal conductor and / or the second metal conductor by a temperature imaging device includes: obtaining the initial temperature information of the first metal conductor and / or the second metal conductor by the temperature imaging device; periodically obtaining the real-time temperature information of the first metal conductor and / or the second metal conductor by the temperature imaging device; the temperature change information is the difference between the real-time temperature information and the initial temperature information.

[0015] In some embodiments, when the parameter change information is within a set threshold range, the method further includes: recording a duration for which the DC power supply applies the DC voltage to the first metal conductor and the second metal conductor.

[0016] In some embodiments, while applying a DC voltage to the first metal conductor and the second metal conductor through the DC power supply, the method includes: placing the dielectric layer substrate, the first metal conductor, and the second metal conductor in a set temperature environment.

[0017] In some embodiments, the voltage range of the DC voltage applied to the first metal conductor and the second metal conductor by the DC power supply is 5 volts to 100 volts; and / or the temperature range of placing the dielectric layer substrate, the first metal conductor and the second metal conductor in a set temperature environment is 60 degrees Celsius to 130 degrees Celsius.

[0018] The present application provides an ion migration detection method. When used, a DC voltage is continuously applied to a first metal conductor and a second metal conductor, and parameter change information is periodically obtained. For example, the parameter change information is the impedance value of the first metal conductor and the second metal conductor. If ion migration occurs, the impedance value of the first metal conductor and the second metal conductor will gradually decrease. Therefore, when the parameter change information is within a set threshold range, the DC voltage is stopped, and the current ion migration detection is completed. In the technical solution of the present application, the ion migration detection using DC voltage can effectively predict the service life of the conductor structure, and the test method of applying DC voltage can simulate actual usage conditions and is more suitable for the current use scenario of the conductor structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the exemplary embodiments of the present application will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present application are shown in an illustrative and non-limiting manner, in which:

[0020] In the drawings, the same or corresponding reference numerals denote the same or corresponding parts.

[0021] Figure 1 A flowchart of the ion migration detection method provided in an embodiment of the present application;

[0022] Figure 2 A schematic diagram of the structure of the ion migration detection method provided in an embodiment of the present application when testing multiple conductor structures;

[0023] Figure 3 This is a flow chart for obtaining temperature information in the ion migration detection method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the purpose, features, and advantages of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of this application.

[0025] With the upgrade of signal protocols, the working mode of high-frequency signals has changed. Taking USB as an example, in USB1.0, the differential signal is AC voltage in the working state, and the differential signal voltage is 0 in sleep mode / shutdown mode; however, the working state of USB2.0 has changed. The differential signal voltage in the sleep state is DC voltage, and the voltage is 0 when the device is turned off or not connected to external devices (such as speakers, Bluetooth USB, etc.).

[0026] It can be seen from this that as the operating mode of high-frequency signals in electronic devices changes, ion migration may also occur between the dual coils of the common-mode inductor, and the existing AC voltage testing method cannot effectively test it.

[0027] An embodiment of the present application provides an ion migration detection method for ion migration detection of a conductor structure 10, wherein the conductor structure 10 includes a dielectric layer substrate, a first metal conductor and a second metal conductor, and the first metal conductor and the second metal conductor are spaced apart on the dielectric layer substrate.

[0028] The material of the dielectric substrate affects the ion migration rate. By replacing the dielectric substrate with a different material, the time it takes for the conductor structure 10 to fail due to ion migration can be determined. A longer time to failure indicates a longer service life for the conductor structure 10.

[0029] First, it can be verified that applying a DC voltage to the conductor can achieve the effectiveness of ion migration.

[0030] After selecting the dielectric layer substrate, two spaced metal electrodes, namely a first metal conductor and a second metal conductor, are printed on the dielectric layer substrate. For example, the metal electrodes are silver Ag electrodes, wherein the spacing distance between the metal electrodes can simulate the actual coil spacing of the common-mode inductor, such as a spacing distance of 290 microns.

[0031] During detection, the first metal conductor and the second metal conductor are connected to different electrodes of a DC power supply, and a DC voltage is applied to the first metal conductor and the second metal conductor through the DC power supply; for example, the first metal conductor is connected to the positive electrode of the DC power supply, and the second metal conductor is connected to the negative electrode of the DC power supply.

[0032] In order to quickly verify whether DC voltage can predict the occurrence of silver ion migration, auxiliary operations can be performed by increasing the voltage and the test temperature; for example, the DC voltage value is 60V and the test temperature is 85°C. The 85°C environment is provided by an oven.

[0033] As the test progresses, parameter change information about the metal electrodes can be acquired in real time or periodically. For example, the parameter change information includes the impedance value between the metal electrodes. Before or in the early stages of the test, this impedance value is high. If ion migration occurs, the impedance value will significantly decrease, indicating a short circuit.

[0034] After the test lasted 1462 hours, the impedance between the metal electrodes dropped from 15GΩ at the start to 0.07GΩ, indicating a near short circuit between the two metal electrodes, caused by silver ion migration. Furthermore, during the test, the appearance of the two electrodes was continuously observed. After 1462 hours, a black mark (silver oxide) appeared between the two silver electrodes, reaching 90%, also confirming the occurrence of silver ion migration.

[0035] like Figure 1 As shown, in the embodiment of the present application, based on the principle that DC voltage can realize ion migration, an ion migration detection method is performed, and the method includes the following steps:

[0036] Step S10: the first metal conductor and the second metal conductor are connected to different electrodes of a DC power supply, and a DC voltage is applied to the first metal conductor and the second metal conductor via the DC power supply.

[0037] The first metal conductor and the second metal conductor are disposed on dielectric substrates of different materials. The ion migration rates of the first metal conductor and the second metal conductor on the dielectric substrates of different materials are different, which can be used to determine whether the dielectric substrate of the current material meets the requirements. In the embodiments of the present application, the specific material of the dielectric substrate is not limited.

[0038] In the embodiment of the present application, the first metal conductor includes a first coil 11, the second metal conductor includes a second coil 12, and the first coil 11 and the second coil 12 are isolated by a dielectric layer substrate; the first coil 11 includes a first pin 111 and a second pin 112, and the second coil 12 includes a third pin 121 and a fourth pin 122, the first pin 111 is connected to the positive pole of the DC power supply, and the second pin 112 and the third pin 121 are respectively connected to the negative pole of the DC power supply.

[0039] The first metal conductor, the second metal conductor and the dielectric layer substrate simulate a stacked common-mode inductor structure, the first pin 111 is connected to the positive pole of the DC power supply and the second pin 112 is connected to the negative pole of the DC power supply to form a test path, and the first pin 111 is connected to the positive pole of the DC power supply and the third pin 121 is connected to the negative pole of the DC power supply to form another test path.

[0040] It can be seen from this that after the DC voltage is applied, two voltage test paths can be formed, thereby simulating the environment where ion migration actually occurs.

[0041] In the embodiment of the present application, the test may be performed on multiple conductor structures 10, including multiple groups of conductor structures 10; Figure 2 As shown, the plurality of first pins 111 are respectively connected to the positive electrode of the DC power supply, and the plurality of second pins 112 and the third pin 121 are respectively connected to the negative electrode of the DC power supply.

[0042] For example, 14 conductor structures 10 can be tested simultaneously, which can effectively improve the test efficiency.

[0043] In the embodiment of the present application, during the test process, if a normal test environment is used, the test time will be longer. For example, the time for some common-mode inductors to have performance problems due to ion migration may exceed 18 months. Therefore, the test can be accelerated by changing the test environment.

[0044] For example, the dielectric layer substrate, the first metal conductor, and the second metal conductor are placed in a set temperature environment. For example, the structure being tested is placed in a high-temperature furnace, which provides a higher test temperature, thereby accelerating ion migration. The temperature range of the dielectric layer substrate, the first metal conductor, and the second metal conductor in the set temperature environment is 60 degrees Celsius to 130 degrees Celsius, for example, 85 degrees Celsius.

[0045] For example, the input DC voltage may be higher than the voltage required in the actual environment, which can also accelerate the ion migration. For example, the DC voltage applied to the first metal conductor and the second metal conductor by the DC power supply has a voltage range of 5V to 100V. For example, the voltage is 60V.

[0046] In the initial state, when metal ions are migrating, there is parameter information between the first metal conductor and the second metal conductor. As the test progresses, the metal ions continue to migrate, and the parameter information will continue to change.

[0047] Step 20: Obtain parameter change information of the first metal conductor and / or the second metal conductor; when the parameter change information is within a set threshold range, the DC power supply stops applying the DC voltage, and the detection is completed.

[0048] For example, the method for obtaining parameter change information of the first metal conductor and / or the second metal conductor includes: obtaining parameter change information of the first coil 11 and obtaining parameter change information between the first coil 11 and the second coil.

[0049] In step S10, the first metal conductor and the second metal conductor can be coils. After a DC voltage is applied, two voltage test paths can be formed, thereby simulating the conditions under which ion migration actually occurs. During the test, the ion migration conditions in the two voltage test paths need to be obtained simultaneously.

[0050] When obtaining parameter change information, the parameter change information can be obtained in real time, or the parameter change information can be obtained periodically. The parameter change information obtained is actual parameter information. If the actual parameter information is within the set threshold range, the DC power supply stops applying the DC voltage, that is, the test is stopped.

[0051] For example, during testing, an auxiliary impedance measurement device can be used to measure impedance change information and determine ion migration based on the impedance change information. Alternatively, an auxiliary temperature measurement device can be used to measure temperature change information and determine ion migration based on the temperature change information.

[0052] A gradually decreasing impedance value indicates ion migration, and the degree of ion migration can be determined based on the measured value. Furthermore, if ion migration occurs, it can cause a short circuit in the metal conductor area. If a short circuit occurs, the temperature of the metal conductor will gradually increase, and the temperature will continue to rise as the degree of ion migration increases.

[0053] A common temperature measurement method is to measure temperature using a temperature sensor. The temperature sensor needs to be placed on the surface of the object being measured. However, due to size limitations and the need to test multiple locations during testing, the cost of temperature testing increases. In the embodiment of the present application, when collecting temperature information, temperature change information of the first metal conductor and / or the second metal conductor is obtained using a temperature imaging device.

[0054] The temperature imaging device is installed outside the high-temperature furnace to obtain its surface temperature. The temperature inside the high-temperature furnace is constant. To prevent the high-temperature furnace temperature from affecting the temperature test, the temperature imaging device is used to obtain initial temperature information of the first and / or second metal conductors during the test. The temperature imaging device is also used periodically to obtain real-time temperature information of the first and / or second metal conductors. The temperature change information is the difference between the real-time temperature information and the initial temperature information, and it is determined whether the temperature difference is within a threshold range.

[0055] Take the common mode inductor test board as an example. Figure 3As shown, the temperature imaging device, i.e., the temperature imager, takes a picture of the initial temperature of the common-mode inductor test board and records the temperature of each common-mode inductor position, which is recorded as temperature T1.

[0056] In the experiment to verify whether silver migration occurs in the common-mode inductor, a temperature map of each common-mode inductor position is taken at each time t and recorded as temperature T2.

[0057] Calculate the operating temperature of each common-mode inductor (T = T2 - T1) and set the threshold temperature Tref. When T > Tref, the common-mode inductor is judged to be faulty (short circuit occurs). The display interface will mark the failure point and automatically count it to calculate the failure rate.

[0058] In this embodiment of the present application, the duration of time a DC power supply applies a DC voltage to the first metal conductor and the second metal conductor is recorded. The timer is started at the beginning of the test and stopped when the test is completed, i.e., when the DC voltage is stopped. This allows the failure time of the conductive structure to be determined, thereby determining the service life of the conductor structure 10 made of the dielectric substrate material.

[0059] The present application provides an ion migration detection method. When used, a DC voltage is continuously applied to a first metal conductor and a second metal conductor, and parameter change information is periodically obtained. For example, the parameter change information is the impedance value of the first metal conductor and the second metal conductor. If ion migration occurs, the impedance value of the first metal conductor and the second metal conductor will gradually decrease. Therefore, when the parameter change information is within a set threshold range, the application of the DC voltage is stopped, and the current ion migration detection is completed. In the technical solution of the present application, the ion migration detection through DC voltage can effectively predict the service life of the conductor structure 10, and the test method of applying DC voltage can simulate actual usage conditions and is more suitable for the current usage scenario of the conductor structure 10.

[0060] In the description of this specification, the reference terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless they are mutually inconsistent.

[0061] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0062] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An ion migration detection method, characterized in that, For ion migration detection of a conductor structure, the conductor structure includes a dielectric layer substrate, a first metal conductor and a second metal conductor, the first metal conductor and the second metal conductor are spaced apart on the dielectric layer substrate, the method comprising: The first metal conductor and the second metal conductor are connected to different electrodes of a DC power supply, and a DC voltage is applied to the first metal conductor and the second metal conductor through the DC power supply; Acquiring parameter change information of the first metal conductor and / or the second metal conductor; When the parameter change information is within the set threshold range, the DC power supply stops applying the DC voltage and the detection is completed.

2. The ion migration detection method according to claim 1, wherein The first metal conductor includes a first coil, the second metal conductor includes a second coil, and the first coil and the second coil are isolated by the dielectric layer substrate; The first coil includes a first pin and a second pin, the second coil includes a third pin and a fourth pin, the first pin is connected to the positive pole of the DC power supply, and the second pin and the third pin are respectively connected to the negative pole of the DC power supply.

3. The ion migration detection method according to claim 2, characterized in that comprising a plurality of groups of the conductor structures; The plurality of first pins are respectively connected to the positive electrode of the DC power supply, and the plurality of second pins and the third pin are respectively connected to the negative electrode of the DC power supply.

4. The ion migration detection method according to claim 2, wherein The method for obtaining parameter change information of the first metal conductor and / or the second metal conductor includes: The parameter change information of the first coil and the parameter change information between the first coil and the second coil are obtained.

5. The ion migration detection method according to claim 4, characterized in that: The parameter change information includes temperature change information and / or impedance value change information.

6. The ion migration detection method according to claim 5, characterized in that: The method for obtaining parameter change information of the first metal conductor and / or the second metal conductor includes: The temperature change information of the first metal conductor and / or the second metal conductor is acquired by a temperature imaging device.

7. The ion migration detection method according to claim 6, characterized in that: The method of obtaining temperature change information of the first metal conductor and / or the second metal conductor by using a temperature imaging device includes: Acquiring initial temperature information of the first metal conductor and / or the second metal conductor by the temperature imaging device; periodically acquiring real-time temperature information of the first metal conductor and / or the second metal conductor through the temperature imaging device; The temperature change information is the difference between the real-time temperature information and the initial temperature information.

8. The ion migration detection method according to any one of claims 1 to 7, characterized in that: When the parameter change information is within a set threshold range, the method further includes: recording a duration for which the DC power supply applies the DC voltage to the first metal conductor and the second metal conductor.

9. The ion migration detection method according to any one of claims 1 to 7, characterized in that: While applying a DC voltage to the first metal conductor and the second metal conductor through the DC power supply, the method includes: The dielectric layer substrate, the first metal conductor and the second metal conductor are placed in a set temperature environment.

10. The ion migration detection method according to claim 9, characterized in that: The voltage range of the DC voltage applied to the first metal conductor and the second metal conductor by the DC power supply is 5V to 100V; and / or The temperature range of placing the dielectric layer substrate, the first metal conductor and the second metal conductor in a set temperature environment is 60 degrees Celsius to 130 degrees Celsius.

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