Measurement method and device for representing packaging aging of silicon carbide MOSFET discrete device

Abstract

The invention discloses a measurement method and device for representing packaging aging of a silicon carbide MOSFET discrete device, and relates to the technical field of semiconductor working condition safety detection. According to the method, the degradation condition of the bonding wire is represented through the electrical parameters of the load current, the original working state of a device does not need to be changed, the load current in a circuit is monitored through a tool for measuring the current, and the load current is compared with the load current obtained through the calculation method; the difference between the two can be used for representing the degradation degree of the bonding wire. Meanwhile, the function to be realized can be realized by randomly changing the two electrical parameters of the load current, and the function can be realized as long as the two parameters are related to the junction temperature and the load current.

Description

TECHNICAL FIELD

[0001] The application discloses a measurement method and device for characterizing packaging aging of a silicon carbide MOSFET discrete device, and relates to the technical field of semiconductor working condition safety detection. BACKGROUND

[0002] With the progress of silicon carbide material technology, various silicon carbide power electronic devices have been developed. Due to the influence of cost, yield, and reliability, silicon carbide power electronic devices are first industrialized in the low-voltage field, and the current commercial product voltage level is 600V-1700V. With the progress of technology, high-voltage silicon carbide devices have emerged and continue to make progress in replacing traditional silicon devices. However, the more severe working environment makes the degradation problem of silicon carbide power devices more prominent.

[0003] The degradation of silicon carbide MOSFET is mainly divided into chip-related degradation and packaging-related degradation, and bond wire fatigue is one of the most common packaging-related degradations in power devices. The main reason for bond wire fatigue is the thermal mechanical stress caused by the mismatch of the thermal expansion coefficients between the parts of the package during device operation. During device operation, due to the continuous impact of large current, temperature fluctuations will generate alternating stress at the bonding position, thereby generating cracks at the bond wire interface. As the working time increases, the stress will continue to increase, eventually causing the cracks to deepen, until the bond wire is completely broken or falls off. In addition to the mechanical stress caused by temperature, the load current will also accelerate the aging of the bond wire. In heavy load converter applications, due to the electromigration effect, a larger drain current will cause voids inside the aluminum bond wire. In addition, the ohmic self-heating effect of the bond wire will also accelerate the aging process. Regardless of the form of bond wire fatigue, it will eventually lead to the open circuit of the bond wire. When one bond wire fails, the current density through other bond wires increases, which will accelerate the aging of other bond wires. When all the bond wires fail, the electrical connection inside the power device is disconnected and stops working, which may cause major system failure and disaster. Therefore, it is necessary to further study the state monitoring method of silicon carbide MOSFET bond wire fatigue. Most scholars are based on electrical parameters to study the bond wire fatigue state monitoring. SUMMARY

[0004] The application provides a measurement method and device for characterizing packaging aging of a silicon carbide MOSFET discrete device, which solves the problems in the prior art.

[0005] In a first aspect, a measurement method for characterizing packaging aging of a silicon carbide MOSFET discrete device includes:

[0006] The mathematical model is established according to the coefficients of the turn-on delay and the maximum change rate of the turn-on drain current.

[0007] According to the mathematical model, an expression of the load current with respect to the turn-on delay and the maximum change rate of the turn-on drain current is obtained.

[0008] The number of broken bonding wires is calculated according to the difference percentage of the calculated load current and the measured load current, wherein the expression of the difference percentage is:

[0009]

[0010] wherein, I 实测 represents the measured load current, I 计算 represents the calculated load current.

[0011] In some implementations, the expression of the turn-on delay and the maximum change rate of the turn-on drain current is:

[0012] t don =e 11 T j +e 12 (2)

[0013]

[0014] wherein, t don represents the turn-on delay, di / dtmax represents the maximum change rate of the turn-on drain current, e 11 , e 12 , e 21 , e 22 , e 23 , e 24 , e 25 represent the coefficients; the coefficients are the fitting coefficients obtained by the first and second fitting of the mathematical model.

[0015] In some implementations, the expression of the load current with respect to the turn-on delay and the maximum change rate of the turn-on drain current is:

[0016]

[0017] The expression of the load current is obtained by formula 4, taking the load current as an unknown quantity:

[0018]

[0019] Wherein, I represents the load current. a, b, c respectively represent the coefficients used in solving the load current, wherein the fitting coefficients e obtained in the calibration process and the turn-on delay t measured in the experiment are contained don And the maximum change rate di / dtmax of the turn-on drain current.

[0020] In some implementations, the number of broken bonding wires is calculated, including:

[0021] The difference percentage when one, two, three, four bonding wires are broken is respectively m1, m2, m3, m4 by shearing the bonding wires;

[0022] When the difference percentage m1

[0023] When the difference percentage m2

[0024] When the difference percentage m3

[0025] The second aspect, the embodiment of the present application provides a kind of measurement device for characterizing silicon carbide MOSFET discrete device package aging, comprising:

[0026] Modeling module, for monitoring the electrical parameters of silicon carbide MOSFET discrete device, establishes mathematical model according to the coefficients of turn-on delay and maximum change rate of turn-on drain current;

[0027] Current calculation module, for obtaining the expression of load current about the turn-on delay and the maximum change rate of turn-on drain current according to the mathematical model;

[0028] Calculation module, for monitoring the measured load current of silicon carbide MOSFET discrete device, the number of broken bonding wires is calculated according to the difference percentage of the calculated load current and the measured load current;Wherein, the expression of the difference percentage is:

[0029]

[0030] Wherein, I 实测 represents the measured load current, I 计算 represents the calculated load current.

[0031] In some implementations, in the modeling module, the expression of turn-on delay and maximum change rate of turn-on drain current is:

[0032] t don =e 11 T j +e12 (2)

[0033] di / dtmax=(e 21 I+e 22 )T j +e 23 I 2 +e 24 I+e 25 (3)

[0034] wherein, t don represents the turn-on delay, di / dtmax represents the maximum change rate of the turn-on drain current, e 11 , e 12 , e 21 , e 22 , e 23 , e 24 , e 25 represents the coefficient; the coefficient is a fitting coefficient obtained by once or twice fitting of a mathematical model.

[0035] In some implementations, in the current calculation module, the expression of the load current with respect to the turn-on delay and the maximum change rate of the turn-on drain current is:

[0036]

[0037] Taking the load current as an unknown quantity, the expression of the load current is obtained by formula 4:

[0038]

[0039] wherein, I represents the load current. a, b, c respectively represent the coefficients used in solving and calculating the load current, wherein the fitting coefficients e obtained in the calibration process and the turn-on delay t don and the maximum change rate of the turn-on drain current di / dtmax measured in the experiment process are contained.

[0040] In some implementations, the measurement module comprises:

[0041] The shearing unit is configured to perform a shearing operation on the bonding wire, and the difference percentage when one, two, three or four bonding wires are broken is respectively taken as m1, m2, m3 or m4.

[0042] The first measurement unit is configured to measure the number of broken bonding wires as 1 when the difference percentage m1 < k ≤ m2.

[0043] The second measurement unit is configured to measure the number of broken bonding wires as 2 when the difference percentage m2 < k ≤ m3.

[0044] The third calculation unit is configured to calculate the number of broken bonding wires as 3 when the difference percentage m3 < k < m4.

[0045] In a third aspect, an electronic device is provided, which includes a memory and a processor, and the memory is configured to store one or more computer instructions, and when the one or more computer instructions are executed by the processor, the method according to the first aspect is implemented.

[0046] In a fourth aspect, a computer storage medium is provided, and the computer storage medium stores a computer program, and when the computer program is executed by a processor, the method according to the first aspect is implemented.

[0047] One or more embodiments of the present application can bring at least the following beneficial effects:

[0048] The present application has the beneficial effect that the method provided by the present application characterizes the degradation of the bonding wire by the electrical parameters of the load current, without changing the original working state of the device, and the load current in the monitoring circuit is measured by the tool, and the load current obtained by the calculation method provided by the present application is compared, and the difference between the two can be used to characterize the degree of degradation of the bonding wire. At the same time, any change of the two electrical parameters related to the load current (similar to the turn-on delay and the maximum change rate of the turn-on drain current) can achieve the function that the present application wants to achieve, as long as the two parameters are related to the junction temperature and the load current, the function can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0049] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0050] Figure 1 is a flow chart of a measurement method for characterizing the aging of a silicon carbide MOSFET discrete device package provided by the embodiments of the present application.

[0051] Figure 2 is a schematic diagram of the prior art for characterizing the degradation of the bonding wire by the ratio of the voltage peak value. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0053] In the prior art, Minghang Xie of Chongqing University in 2023 established a double-pulse test circuit analytical model considering parasitic parameters for a silicon carbide MOSFET packaged by Kelvin, found that the voltage oscillation peak value between the Kelvin source and the power source will increase with the increase of the parasitic inductance of the power source bonding wire through the analysis of the turn-on process of the device, and therefore proposed that the voltage oscillation peak value can be used to monitor the degradation of the bonding wire. Through analysis, it is found that the voltage oscillation peak value between the Kelvin source and the power source of the silicon carbide MOSFET is related to the parasitic inductance of the bonding wire and the change rate of the drain current, however, the change rate of the drain current will be affected by temperature, load current, bus voltage, resulting in that the monitoring will also be affected by these factors. Therefore, the technical solution selects the ratio of the voltage oscillation peak value between the Kelvin source and the power source to the voltage oscillation on a section of the power loop as a monitoring parameter, as shown in the formula, so as to eliminate the change rate of the drain current in the formula, and eliminate the influence of factors such as temperature, load current, bus voltage. A newly defined electrical parameter is used to represent the degradation of the bonding wire, and the technical solution shows that the value of k increases with the deepening of the degradation of the bonding wire, and the percentage change of k can be used to represent the number of the falling off of the bonding wire. Figure 2

[0054] Embodiment one:

[0055] Figure 1 A flow chart of a measurement method for representing the aging of a silicon carbide MOSFET discrete device package is shown, as shown in Figure 1 The measurement method for representing the aging of a silicon carbide MOSFET discrete device package provided by the embodiment includes:

[0056] S1, monitoring the electrical parameters of the silicon carbide MOSFET discrete device, and establishing a mathematical model according to the coefficients of the turn-on delay and the maximum change rate of the turn-on drain current;

[0057] S2, obtaining an expression of the load current with respect to the turn-on delay and the maximum change rate of the turn-on drain current according to the mathematical model;

[0058] ​S3, monitoring the measured load current of the silicon carbide MOSFET discrete device, and calculating the number of broken bonding wires according to the difference percentage of the calculated load current and the measured load current; wherein the expression of the difference percentage is:

[0059]

[0060] Through the double-pulse experiment, the mathematical model of the device is obtained offline, and then the Buck experiment is performed to simulate the running condition of the device under the working condition, and the turn-on delay t don and the maximum change rate di / dtmax of the turn-on drain current are obtained. 计算 Before the bonding wire of the device is degraded, there is almost no difference between the calculated I and the measured I, and after the first step of calibration, the degradation of the bonding wire of the device can be monitored online, and the turn-on delay t don and the maximum change rate di / dtmax of the turn-on drain current are obtained. 实测 The difference between the two I is compared, and when the difference percentage k exceeds a certain value m, the degree of bonding wire degradation can be judged by the size of the value.

[0061] Wherein, I 实测 represents the measured load current, and I 计算 represents the calculated load current.

[0062] In some implementations, a mathematical model of the silicon carbide MOSFET discrete device to be monitored is established to obtain the expressions of the turn-on delay t don and the maximum change rate di / dtmax of the turn-on drain current about the junction temperature and the load current, that is, to obtain each coefficient in the following formula as a mathematical model of a healthy device:

[0063] The expression of the turn-on delay and the maximum change rate di / dtmax of the turn-on drain current is:

[0064] t don =e 11 T j +e 12 (2)

[0065] di / dtmax=(e 21 I+e 22 )T j +e 23 I 2 +e 24 I+e 25 (3)

[0066] Wherein, t donrepresents the turn-on delay, di / dtmax represents the maximum rate of change of the drain current, e 11 12 21 22 23 24 25 represents the coefficient; the coefficient is a fitting coefficient obtained by first or second fitting of a mathematical model.

[0067] By reversing the above two formulas, the expression of the load current with respect to the turn-on delay and the maximum rate of change of the drain current is:

[0068]

[0069] Taking the load current as an unknown quantity, the expression of the load current is obtained by formula (4):

[0070]

[0071] wherein I represents the load current, a, b, and c respectively represent coefficients used in solving and calculating the load current, wherein the fitting coefficient e obtained in the calibration process and the turn-on delay t don and the maximum rate of change of the drain current di / dtmax measured in the experiment process are contained.

[0072] When the bonding wire of the device is degraded, the two electrical parameters of the turn-on delay t don and the maximum rate of change of the drain current di / dtmax will respectively drift positively and negatively, since the maximum rate of change of the drain current di / dtmax is greatly affected by the degradation of the bonding wire, accordingly, the value of the load current calculated according to the mathematical model of the healthy device will be less than the actual load current, and the number of broken bonding wires can be judged according to the percentage difference, and the degradation condition can be judged.

[0073] Further, in S3, the number of broken bonding wires is calculated, including:

[0074] The difference percentage when one, two, three, or four bonding wires are broken is respectively counted as m1, m2, m3, and m4 by shearing the bonding wire;

[0075] When the difference percentage m1 < k ≤ m2, the number of broken bonding wires is calculated as 1;

[0076] When the difference percentage m2 < k ≤ m3, the number of broken bonding wires is calculated as 2;

[0077] ​​​​​​When the difference percentage m3 < k ≤ m4, the number of broken bonds of the bonding wire is calculated as 3.

[0078] First, the mathematical model of the device is obtained by off-line double pulse experiment, then the device is subjected to Buck experiment to simulate the running condition of the device under working condition, and the opening delay t of the device at this time is obtained don And the two electrical parameters of the maximum change rate di / dtmax of the opening drain current are substituted into the above formula (5) to calculate I 计算 , and the device does not have bonding wire degradation, and there is almost no difference between I 计算 And I 实测 Then the bonding wire is cut repeatedly, and the value of k is calculated each time to determine the m1 when one bonding wire is broken, the m2 when two bonding wires are broken, the m3 when three bonding wires are broken, and the m4 when four bonding wires are broken, thereby providing a reference for online monitoring.

[0079] The opening delay t of the device is obtained don And the two electrical parameters of the maximum change rate di / dtmax of the opening drain current are obtained by the PCB board, the opening delay is the time required from the gate voltage rising to 10% to the drain-source voltage dropping to 90%, and the maximum change rate of the opening drain current is obtained by the inductive voltage of the Rogowski coil, that is:

[0080]

[0081] The part of calculating the value of k is realized by code, the double pulse data is imported in matlab, the specific mathematical expression is obtained by fitting, and the code for calculating I is written, and each time the opening delay t don And the maximum change rate di / dtmax of the opening drain current are input into the code to obtain I 计算 , and the value of k is calculated by formula (1), so that the degree of bonding wire degradation can be judged.

[0082] Example two:

[0083] The embodiment of the application provides a kind of measurement device for characterizing silicon carbide MOSFET discrete device package aging, comprising:

[0084] Modeling module, for monitoring the electrical parameters of silicon carbide MOSFET discrete device, establishes mathematical model according to the coefficients of opening delay and maximum change rate of opening drain current;

[0085] Current calculation module, for obtaining the expression of load current about the opening delay and the maximum change rate of opening drain current according to the mathematical model;

[0086] The measuring module is configured to monitor a measured load current of the silicon carbide MOSFET discrete device, and calculate the number of broken bonding wires according to a difference percentage of the calculated load current and the measured load current; wherein the expression of the difference percentage is:

[0087]

[0088] wherein I 实测 represents the measured load current, I 计算 represents the calculated load current.

[0089] Further, in the modeling module, the expression of the turn-on delay and the maximum change rate of the turn-on drain current is:

[0090] t don =e 11 T j +e 12 (2)

[0091] di / dtmax=e 21 I+e 22 )T j +e 23 I 2 +e 24 I+e 25 (3)

[0092] wherein t don represents the turn-on delay, di / dtmax represents the maximum change rate of the turn-on drain current, e 11 , e 12 , e 21 , e 22 , e 23 , e 24 , e 25 represent the coefficients; the coefficients are fitting coefficients obtained by first-order and second-order fitting of a mathematical model.

[0093] Further, in the current calculation module, the expression of the load current about the turn-on delay and the maximum change rate of the turn-on drain current is:

[0094]

[0095] Taking the load current as an unknown quantity, the expression of the load current is obtained through formula (4):

[0096]

[0097] Wherein, I represents the load current. a, b, c respectively represent the coefficients used in solving the load current, which contains the fitting coefficient e obtained in the calibration process and the turn-on delay t measured in the experiment don And the maximum change rate di / dtmax of the turn-on drain current.

[0098] Further, the calculation module comprises:

[0099] The shearing unit is configured to perform a shearing operation on the bonding wire, and the difference percentage when one, two, three or four bonding wires are broken is respectively m1, m2, m3 or m4.

[0100] The first calculation unit is configured to calculate the number of broken bonding wires as one when the difference percentage m1 < k < m2.

[0101] The second calculation unit is configured to calculate the number of broken bonding wires as two when the difference percentage m2 < k < m3.

[0102] The third calculation unit is configured to calculate the number of broken bonding wires as three when the difference percentage m3 < k < m4.

[0103] Embodiment three:

[0104] The embodiment also provides an electronic device comprising a memory and a processor, wherein the memory is configured to store one or more computer instructions, and the one or more computer instructions are configured to be executed by the processor to implement the method of embodiment one.

[0105] In actual applications, the processor can be an Application Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), a Digital Signal Processing Device (DSPD), a Programmable Logic Device (PLD), a Field Programmable Gate Array (FPGA), a controller, a microcontroller (MCU), a microprocessor, or other electronic elements, which are configured to execute the method in the above embodiments.

[0106] The method implemented by the embodiment is as shown in the content of embodiment one.

[0107] Embodiment four:

[0108] The embodiment also provides a computer storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executed by one or more processors to implement the method of the embodiment one.

[0109] The computer readable storage medium can be implemented by any type of volatile or nonvolatile storage devices or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk.

[0110] The method implemented by the embodiment is shown in the content of the embodiment one.

[0111] In several embodiments provided by the embodiments of the present application, it should be understood that the disclosed system and method can also be implemented in other ways. The system and method embodiments described above are only illustrative.

[0112] It should be noted that in this paper, the terms "first", "second" and the like in the description and claims of the application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. The terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0113] Although the embodiments of the present application have been disclosed with reference to the above embodiments, the above description is merely used to understand the present application and is not used to limit the present application. Any person skilled in the art, without departing from the spirit and scope of the present application, can make any modification and change in the form and details of the embodiments, but the patent protection scope of the present application should be subject to the scope defined by the appended claims.

Claims

1. A measurement method for characterizing the aging of silicon carbide MOSFET discrete device packages, characterized in that, include: Monitor the electrical parameters of silicon carbide MOSFET discrete devices and establish a mathematical model based on the coefficients of turn-on delay and maximum change rate of turn-on drain current. Based on the mathematical model, an expression for the load current with respect to the turn-on delay and the maximum rate of change of the turn-on drain current is obtained; The measured load current of the silicon carbide MOSFET discrete device is monitored, and the number of broken bond wires is calculated based on the percentage difference between the calculated load current and the measured load current; wherein, the expression for the percentage difference is: Among them, I 实测 I represents the measured load current. 计算 This indicates the calculation of the load current.

2. The method according to claim 1, characterized in that, The expressions for the turn-on delay and the maximum rate of change of the turn-on drain current are: t don =e 11 T j +e 12 (2) of / dtmax=(and 21 I+e 22 )T j +e 23 THE 2 +e 24 I+e 25 (3) Among them, t don Indicates the turn-on delay, di / dtmax represents the maximum rate of change of the turn-on drain current, and e 11 e 12 e 21 e 22 e 22 e 24 e 25 The coefficients are defined as fitting coefficients obtained by first-order and second-order fitting of a mathematical model.

3. The method according to claim 2, characterized in that, The expression for the load current with respect to the turn-on delay and the maximum rate of change of the turn-on drain current is: Treating the load current as an unknown quantity, the expression for the load current is obtained through Formula 4: Where I represents the load current. a, b, and c represent the coefficients used in calculating the load current, including the fitting coefficient e obtained during calibration and the turn-on delay t measured during the experiment. don And the maximum rate of change of the turn-on drain current, di / dtmax.

4. The method according to claim 3, characterized in that, The number of broken bond wires was calculated, including: The bonding wires are cut, and the percentage difference when one, two, three, and four bonding wires break is recorded as m1, m2, m3, and m4, respectively. When the percentage difference m1 < k ≤ m2, the number of broken bond wires is calculated to be 1; When the percentage difference m2 < k ≤ m3, the number of broken bond wires is calculated to be 2; When the percentage difference m3 < k ≤ m4, the number of broken bond lines is calculated to be 3.

5. A measuring device for characterizing the aging of silicon carbide MOSFET discrete device packages, characterized in that, include: The modeling module is used to monitor the electrical parameters of silicon carbide MOSFET discrete devices and establish a mathematical model based on the coefficients of the turn-on delay and the maximum rate of change of the turn-on drain current. The current calculation module is used to obtain an expression for the load current with respect to the turn-on delay and the maximum rate of change of the turn-on drain current, based on the mathematical model. The measurement module is used to monitor the measured load current of the silicon carbide MOSFET discrete device, and calculate the number of broken bond wires based on the percentage difference between the calculated load current and the measured load current; wherein, the expression for the percentage difference is: Among them, I 实测 I represents the measured load current. 计算 This indicates the calculation of the load current.

6. The apparatus according to claim 5, characterized in that, In the modeling module, the expressions for turn-on delay and the maximum rate of change of turn-on drain current are: t don =e 11 T j +e 12 (2) of / dtmax=(and 21 I+e 22 )T j +e 23 THE 2 +e 24 I+e 25 (3) Among them, t d(on) This indicates the turn-on delay, and di / dtmax indicates the maximum turn-on drain current. e 11 e 12 e 21 e 22 e 23 e 24 e 25 This represents the coefficient.

7. The apparatus according to claim 6, characterized in that, In the current calculation module, the expression for the load current with respect to the turn-on delay and the maximum rate of change of the turn-on drain current is: Treating the load current as an unknown quantity, the expression for the load current is obtained through Formula 4: Where I represents the load current. a, b, and c represent the coefficients used in calculating the load current, including the fitting coefficient e obtained during calibration and the turn-on delay t measured during the experiment. don And the maximum rate of change of the turn-on drain current, di / dtmax.

8. The apparatus according to claim 7, characterized in that, The calculation module includes: The cutting unit is used to cut the bonding wires, and the percentage difference when one, two, three, and four bonding wires break is recorded as m1, m2, m3, and m4, respectively. The first calculation unit is used to calculate the number of broken bonding wires as 1 when the difference percentage m1 < k ≤ m2; The second calculation unit is used to calculate the number of broken bond wires as 2 when the difference percentage m2 < k ≤ m3; The third calculation unit is used to calculate the number of broken bond lines as 3 when the difference percentage m3 < k ≤ m4.

9. An electronic device, characterized in that, The system includes a memory and a processor, the memory being used to store one or more computer instructions, wherein the one or more computer instructions, when executed by the processor, implement the method as described in any one of claims 1-4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, is used to implement the method as described in any one of claims 1-4.

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