A junction temperature test sorting method, system, computer and storage medium

Abstract

The application relates to the technical field of semiconductors, and provides a junction temperature test sorting method, a system, a computer and a storage medium, the junction temperature test sorting method comprises the following steps: calibrating the voltage temperature sensitivity coefficient of an LED chip; setting a test environment temperature, obtaining a test current basic value and a test parameter set, and performing a plurality of transient voltage tests and a plurality of steady-state voltage tests; based on the voltage temperature sensitivity coefficient, the test environment temperature, a plurality of test transient voltage values and a plurality of test steady-state voltage values, obtaining a plurality of junction temperatures; based on the test current basic value, the test parameter set and the plurality of junction temperatures, fitting to obtain a current-junction temperature relationship curve; obtaining a rated working current, based on the rated working current and the current-junction temperature relationship curve, obtaining a target junction temperature; and based on historical junction temperature data and the target junction temperature, sorting the LED chip. Through the above method, wafer-level high-stability, high-precision and high-efficiency junction temperature testing is realized, and mass production sorting is matched.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a junction temperature testing and sorting method, system, computer, and storage medium. Background Technology

[0002] During operation, LED chips release light and heat. As heat accumulates, the temperature of the junction region will rise. The junction temperature of the LED chip affects photoelectric parameters such as luminous flux, light output efficiency, and forward voltage. It is a core parameter that determines its long-term reliability, luminous efficiency stability, and wavelength drift characteristics.

[0003] Excessive junction temperature can lead to increased chip heating, which in turn can cause problems such as brightness decay, thermal quenching, and wavelength redshift. High-power LED chips have even higher requirements for junction temperature consistency in production applications. Therefore, rapid and accurate testing of LED junction temperature is of great significance.

[0004] Traditional junction temperature testing methods include infrared thermal imaging and laser scintillation, which require large equipment such as high-precision infrared cameras and laser emitters. These devices are costly and bulky, making them difficult to integrate and apply to conventional wafer sorting systems. Infrared detection is susceptible to interference from ambient light and wafer surface reflectivity, resulting in insufficient test stability and accuracy. Infrared detection and laser scintillation tests are time-consuming, and the equipment debugging and benchmark calibration processes are cumbersome, leading to large human error and poor test consistency, which further negatively impacts the stability and accuracy of the tests. In addition, traditional junction temperature testing methods are mostly device-level tests and cannot be directly tested in the unpackaged wafer stage, increasing testing procedures and production costs, making them difficult to adapt to mass production sorting. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a junction temperature testing and sorting method, system, computer, and storage medium. This invention seeks to solve the technical problems of insufficient stability, accuracy, and testing efficiency in existing junction temperature testing technologies, which are mostly device-level tests and cannot be performed at the unpackaged wafer stage.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: A junction temperature testing and sorting method includes the following steps: Calibrate the voltage temperature sensitivity coefficient of the LED chip; Set the test environment temperature, obtain the basic value of the test current and the test parameter set, and perform several transient voltage tests and several steady-state voltage tests on the LED chip at the test environment temperature to obtain several test transient voltage values ​​and several test steady-state voltage values. Based on the voltage temperature sensitivity coefficient, the test environment temperature, several test transient voltage values, and several test steady-state voltage values, several junction temperatures are obtained; Based on the baseline value of the test current, the set of test parameters, and several junction temperatures, a current-junction temperature relationship curve is obtained by fitting. Obtain the rated operating current, and based on the rated operating current and the current-junction temperature relationship curve, obtain the target junction temperature; Historical junction temperature data is acquired, and the LED chips are sorted based on the historical junction temperature data and the target junction temperature.

[0007] Furthermore, the step of calibrating the voltage temperature sensitivity coefficient of the LED chip includes: Obtain the first calibration temperature, the second calibration temperature, and the calibration current; The LED chip is placed in a constant temperature oven, the constant temperature oven is stabilized at the first calibrated temperature, and the calibrated current is applied to the LED chip to obtain the first positive voltage. The constant temperature oven is stabilized at the second calibrated temperature, and the calibrated current is applied to the LED chip to obtain the second positive voltage; The voltage temperature sensitivity coefficient is calculated based on the first positive voltage, the second positive voltage, the first calibration temperature, and the second calibration temperature.

[0008] Furthermore, the range of the calibration current is 0.05mA to 0.1mA.

[0009] Furthermore, the test parameter set includes several test current coefficients and steady-state times. The step of performing several transient voltage tests and several steady-state voltage tests on the LED chip at the test ambient temperature based on the basic test current value and the test parameter set to obtain several test transient voltage values ​​and several test steady-state voltage values ​​includes: Based on the aforementioned basic value of the test current and several of the aforementioned test current coefficients, several test currents are calculated. The LED chip is subjected to the test current at the test ambient temperature to obtain the test transient voltage value; Based on the steady-state time, the steady-state time point of the LED chip is determined, and when the steady-state time point is reached, the test steady-state voltage value is obtained.

[0010] Furthermore, the step of obtaining several junction temperatures based on the voltage temperature sensitivity coefficient, the test environment temperature, several transient test voltage values, and several steady-state test voltage values ​​includes: The voltage difference is calculated based on the test steady-state voltage value and the test transient voltage value; The temperature rise value is calculated based on the voltage difference and the voltage temperature sensitivity coefficient. The junction temperature is calculated based on the temperature rise and the ambient temperature of the test environment.

[0011] Furthermore, the step of fitting a current-junction temperature relationship curve based on the baseline test current value, the test parameter set, and several junction temperatures includes: Using the test current as the abscissa value and the junction temperature as the ordinate value, a curve fitting point is established; The current-junction temperature relationship curve is obtained by fitting several of the aforementioned fitting points.

[0012] Furthermore, the step of acquiring historical junction temperature data and sorting the LED chips based on the historical junction temperature data and the target junction temperature includes: Several application scenarios are obtained, and several junction temperature ranges are determined based on the historical junction temperature data and the several application scenarios; A junction temperature threshold is determined based on the historical junction temperature data. If the target junction temperature is greater than or equal to the junction temperature threshold, the LED chip is scrapped. If the target junction temperature is less than the junction temperature threshold, the junction temperature range into which the target junction temperature falls is determined, so as to sort the LED chips.

[0013] A junction temperature testing and sorting system, employing the junction temperature testing and sorting method described in the above technical solution, the system comprising: The calibration module is used to calibrate the voltage-temperature sensitivity coefficient of the LED chip. The testing module is used to set the test environment temperature, obtain the basic value of the test current and the test parameter set, and perform several transient voltage tests and several steady-state voltage tests on the LED chip at the test environment temperature based on the basic value of the test current and the test parameter set, so as to obtain several test transient voltage values ​​and several test steady-state voltage values. The calculation module is used to obtain several junction temperatures based on the voltage temperature sensitivity coefficient, the test environment temperature, several test transient voltage values, and several test steady-state voltage values; The fitting module is used to fit a current-junction temperature relationship curve based on the basic value of the test current, the set of test parameters, and several junction temperatures. The result module is used to obtain the rated operating current and, based on the rated operating current and the current-junction temperature relationship curve, to obtain the target junction temperature. The sorting module is used to acquire historical junction temperature data and sort the LED chips based on the historical junction temperature data and the target junction temperature.

[0014] A computer includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the junction temperature testing and sorting method as described above.

[0015] A storage medium storing a computer program, which, when executed by a processor, implements the junction temperature testing and sorting method as described in the above technical solution.

[0016] Compared with existing technologies, the advantages of this invention are as follows: In the chip optoelectronic testing stage before wafer sorting, specialized multi-current point transient voltage testing and steady-state voltage testing are introduced. Based on the transient voltage and steady-state voltage test results corresponding to multiple test currents, combined with the voltage temperature sensitivity coefficient calibrated for the chip, the relationship between the test current and the junction temperature is obtained. The test current and the corresponding junction temperature values ​​form coordinate points, and the relationship curve between the two is fitted. Thus, the target junction temperature of the LED chip is obtained based on the rated operating current. There is no need to introduce related equipment such as infrared imaging and laser flashing, and junction temperature testing can be completed without the introduction of manual equipment operation. The LED chips are sorted based on the junction temperature test results. This junction temperature testing and sorting method has the advantages of high stability, high accuracy, and high efficiency. It does not require testing after packaging. It achieves efficient junction temperature testing at the wafer level, solving the problem that traditional junction temperature testing cannot be adapted to mass production sorting. It adds a classification dimension to chip sorting, matching chips with different junction temperature levels to products in different application scenarios, which is beneficial to improving product consistency and reliability. Attached Figure Description

[0017] Figure 1 This is a flowchart of the junction temperature testing and sorting method in the first embodiment of the present invention; Figure 2 This is a structural block diagram of the junction temperature testing and sorting system in the second embodiment of the present invention; The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0018] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0019] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] Please see Figure 1 The junction temperature testing and sorting method in the first embodiment of the present invention includes the following steps: Step S10: Calibrate the voltage temperature sensitivity coefficient of the LED chip; Preferably, the inherent photothermosensitive characteristic of the LED chip, where the forward voltage changes linearly with temperature, is used to calibrate the coefficient of the relationship between the forward voltage and temperature of a single chip.

[0022] Step S10 includes: S110: Obtain the first calibration temperature, the second calibration temperature, and the calibration current; In S110, the range of the calibration current is 0.05mA~0.1mA.

[0023] Preferably, the first calibration temperature is lower than the second calibration temperature, and the calibration process adopts a method of gradually increasing the ambient temperature. The calibration current is a small current, and when its value range is 0.05mA~0.1mA, it can avoid chip self-heating and ensure that the voltage temperature sensitivity coefficient only reflects the relationship between ambient temperature and positive voltage, which is beneficial to improving the accuracy of the test. Specifically, the calibration current in this embodiment is 0.1mA.

[0024] S120: Place the LED chip in a constant temperature oven, stabilize the constant temperature oven at the first calibrated temperature, and apply the calibrated current to the LED chip to obtain the first positive voltage; Preferably, the first calibration temperature is 25°C and the first positive voltage is 2.519V.

[0025] S130: Stabilize the constant temperature oven at the second calibrated temperature, and apply the calibrated current to the LED chip to obtain the second positive voltage; Preferably, the second calibration temperature is 85°C. The constant temperature oven is heated to 85°C, and the second positive voltage is measured to be 2.416V.

[0026] S140: Calculate the voltage temperature sensitivity coefficient based on the first positive voltage, the second positive voltage, the first calibration temperature, and the second calibration temperature.

[0027] Preferably, the voltage temperature sensitivity coefficient is obtained by dividing the difference between the second positive voltage and the first positive voltage by the difference between the second calibration temperature and the first calibration temperature. In this embodiment, the voltage temperature sensitivity coefficient is -0.001583V / ℃.

[0028] Step S20: Set the test environment temperature, obtain the basic value of the test current and the test parameter set, and perform several transient voltage tests and several steady-state voltage tests on the LED chip at the test environment temperature to obtain several test transient voltage values ​​and several test steady-state voltage values. Preferably, the test environment temperature is 25℃, the test current base value is 700mA, different proportions of current are sequentially applied to the chip, and the transient voltage and the steady-state voltage after thermal stabilization are collected respectively to calculate the corresponding junction temperature. The time required for thermal stabilization is required to ensure thermal balance, without affecting the test speed, and without allowing heat to diffuse to the substrate.

[0029] In step S20, the test parameter set includes several test current coefficients and steady-state time, and step S20 includes: S210: Based on the basic value of the test current and several test current coefficients, calculate several test currents; Preferably, the test current coefficients are 0.6, 0.8, 1 and 1.2 respectively, and the four test currents are calculated to be 420mA, 560mA, 700mA and 840mA respectively, and the steady state time is the time elapsed for thermal stabilization.

[0030] S220: Apply the test current to the LED chip at the test ambient temperature to obtain the test transient voltage value; Preferably, when a current of 420mA is applied, the corresponding transient voltage value is measured to be 2.846V; when a current of 560mA is applied, the corresponding transient voltage value is measured to be 2.894V; when a current of 700mA is applied, the corresponding transient voltage value is measured to be 2.943V; and when a current of 840mA is applied, the corresponding transient voltage value is measured to be 2.978V.

[0031] S230: Based on the steady-state time, determine the steady-state time point of the LED chip, and when the steady-state time point is reached, obtain the test steady-state voltage value.

[0032] Preferably, the steady-state time is 100ms. The steady-state time point is reached 100ms after the test current is applied. After applying a current of 420mA, the corresponding steady-state voltage value is measured to be 2.818V; after applying a current of 560mA, the corresponding steady-state voltage value is measured to be 2.866V; after applying a current of 700mA, the corresponding steady-state voltage value is measured to be 2.913V; and after applying a current of 840mA, the corresponding steady-state voltage value is measured to be 2.944V.

[0033] Step S30: Based on the voltage temperature sensitivity coefficient, the test environment temperature, several test transient voltage values, and several test steady-state voltage values, obtain several junction temperatures; By introducing transient voltage testing and steady-state voltage testing at multiple current points, and based on the transient voltage and steady-state voltage test results corresponding to multiple test currents, combined with the voltage temperature sensitivity coefficient calibrated on the chip, the junction temperature corresponding to the test current is obtained, so as to further determine the relationship between the junction temperature and the operating current.

[0034] Step S30 includes: S310: Calculate the voltage difference based on the test steady-state voltage value and the test transient voltage value; S320: The temperature rise value is calculated based on the voltage difference and the voltage temperature sensitivity coefficient; S330: The junction temperature is calculated based on the temperature rise value and the test environment temperature.

[0035] Preferably, in steps S310-S330, the voltage difference is divided by the voltage temperature sensitivity coefficient to obtain the temperature rise value. The temperature rise value is added to the test environment temperature to obtain the junction temperature. After applying a current of 420mA, the corresponding junction temperature is 42.52℃; after applying a current of 560mA, the corresponding junction temperature is 42.81℃; after applying a current of 700mA, the corresponding junction temperature is 44.11℃; and after applying a current of 840mA, the corresponding junction temperature is 46.42℃.

[0036] Step S40: Based on the baseline value of the test current, the set of test parameters, and several junction temperatures, fit and obtain the current-junction temperature relationship curve; Establish a coordinate system with the horizontal axis representing the current value and the vertical axis representing the temperature value. The basic test current value and several test currents obtained from the test parameter set are used as the horizontal axis, and the corresponding junction temperatures are used as the vertical axis.

[0037] Step S40 includes: S410: Use the test current as the horizontal axis value and the junction temperature as the vertical axis value to establish curve fitting points; S420: Obtain the current-junction temperature relationship curve based on several fitting points.

[0038] Preferably, in this embodiment, four coordinate points, namely the four curve fitting points, can be established based on four horizontal coordinate values ​​and four vertical coordinate values.

[0039] Step S50: Obtain the rated operating current, and based on the rated operating current and the current-junction temperature relationship curve, obtain the target junction temperature; Preferably, in this embodiment, the rated operating current is 2000mA and the target junction temperature is 104.5℃.

[0040] Step S60: Obtain historical junction temperature data, and sort the LED chips based on the historical junction temperature data and the target junction temperature.

[0041] Understandably, in the chip optoelectronic testing stage before wafer sorting, the junction temperature test in this embodiment can be introduced to complete the junction temperature test without the need for infrared imaging, laser scintillation, or other related equipment and manual operation. The LED chips are then sorted based on the junction temperature test results. This junction temperature test sorting method has the advantages of high stability, high accuracy, and high efficiency. Furthermore, it eliminates the need for post-packaging testing, achieving efficient junction temperature testing at the wafer level. This solves the problem that traditional junction temperature testing methods cannot be adapted to mass production sorting, adds a classification dimension to chip sorting, and matches chips with different junction temperature levels to products in different application scenarios, which is beneficial to improving product consistency and reliability.

[0042] Step S60 includes: S610: Obtain several application scenarios, and determine several junction temperature ranges based on the historical junction temperature data and the several application scenarios; Preferably, under the same rated operating current, the junction temperature range of 100℃~105℃ corresponds to vehicle lighting application scenarios, and the junction temperature range of 105℃~110℃ corresponds to lighting application scenarios.

[0043] S620: Determine the junction temperature threshold based on the historical junction temperature data. If the target junction temperature is greater than or equal to the junction temperature threshold, then the LED chip is scrapped. Preferably, the junction temperature threshold is 110°C. Specifically, when the target junction temperature falls between 110°C and 115°C, the LED chip is considered a defective product and is scrapped.

[0044] S630: If the target junction temperature is less than the junction temperature threshold, then determine the junction temperature range into which the target junction temperature falls, so as to sort the LED chips.

[0045] Preferably, after testing 20 wafers, the historical junction temperature data shows that: 76.4% of the junction temperature test results fall within the range of 100℃ to 105℃, 21.7% of the junction temperature test results fall within the range of 105℃ to 110℃, and 1.9% are scrapped.

[0046] Please see Figure 2 The junction temperature testing and sorting system provided in the second embodiment of the present invention applies the junction temperature testing and sorting method described in the first embodiment above. The system includes: Calibration module 10 is used to calibrate the voltage temperature sensitivity coefficient of the LED chip; The calibration module 10 includes: The first unit is used to obtain the first calibration temperature, the second calibration temperature, and the calibration current; The first unit is specifically used for: The rated current range is 0.05mA to 0.1mA.

[0047] The second unit is used to place the LED chip in a constant temperature oven, stabilize the constant temperature oven at the first calibrated temperature, and pass the calibrated current into the LED chip to obtain the first positive voltage. The third unit is used to stabilize the constant temperature oven at the second calibrated temperature, and to pass the calibrated current into the LED chip to obtain the second positive voltage. The fourth unit is used to calculate the voltage temperature sensitivity coefficient based on the first forward voltage, the second forward voltage, the first calibration temperature, and the second calibration temperature.

[0048] The test module 20 is used to set the test environment temperature, obtain the basic value of the test current and the test parameter set, and perform several transient voltage tests and several steady-state voltage tests on the LED chip at the test environment temperature based on the basic value of the test current and the test parameter set, so as to obtain several test transient voltage values ​​and several test steady-state voltage values. In the test module 20, the test parameter set includes several test current coefficients and steady-state times. The test module 20 includes: The fifth unit is used to calculate several test currents based on the base value of the test current and several test current coefficients; The sixth unit is used to apply the test current to the LED chip at the test ambient temperature to obtain the test transient voltage value; The seventh unit is used to determine the steady-state time point of the LED chip based on the steady-state time, and to obtain the test steady-state voltage value when the steady-state time point is reached.

[0049] Calculation module 30 is used to obtain several junction temperatures based on the voltage temperature sensitivity coefficient, the test environment temperature, several test transient voltage values, and several test steady-state voltage values; The computing module 30 includes: The eighth unit is used to calculate the voltage difference based on the test steady-state voltage value and the test transient voltage value; The ninth unit is used to calculate the temperature rise value based on the voltage difference and the voltage temperature sensitivity coefficient; The tenth unit is used to calculate the junction temperature based on the temperature rise value and the test environment temperature.

[0050] The fitting module 40 is used to fit a current-junction temperature relationship curve based on the basic value of the test current, the set of test parameters, and several junction temperatures. The fitting module 40 includes: The eleventh unit is used to establish curve fitting points by taking the test current as the abscissa value and the junction temperature as the ordinate value. The twelfth unit is used to obtain the current-junction temperature relationship curve based on several of the fitting points.

[0051] Result module 50 is used to obtain the rated operating current and, based on the rated operating current and the current-junction temperature relationship curve, obtain the target junction temperature. The sorting module 60 is used to acquire historical junction temperature data and sort the LED chips based on the historical junction temperature data and the target junction temperature.

[0052] The sorting module 60 includes: The thirteenth unit is used to acquire several application scenarios and determine several junction temperature ranges based on the historical junction temperature data and the several application scenarios. The fourteenth unit is used to determine the junction temperature threshold based on the historical junction temperature data. If the target junction temperature is greater than or equal to the junction temperature threshold, the LED chip is scrapped. The fifteenth unit is used to determine the junction temperature range into which the target junction temperature falls if the target junction temperature is less than the junction temperature threshold, so as to sort the LED chips.

[0053] The third embodiment of the present invention provides a computer, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the junction temperature test and sorting method as described in the first embodiment.

[0054] The fourth embodiment of the present invention provides a storage medium on which a computer program is stored, which, when executed by a processor, implements the junction temperature testing and sorting method as described in the first embodiment.

[0055] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0056] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A junction temperature testing and sorting method, characterized in that, Includes the following steps: Calibrate the voltage temperature sensitivity coefficient of the LED chip; Set the test environment temperature, obtain the basic value of the test current and the test parameter set, and perform several transient voltage tests and several steady-state voltage tests on the LED chip at the test environment temperature to obtain several test transient voltage values ​​and several test steady-state voltage values. Based on the voltage temperature sensitivity coefficient, the test environment temperature, several test transient voltage values, and several test steady-state voltage values, several junction temperatures are obtained; Based on the baseline value of the test current, the set of test parameters, and several junction temperatures, a current-junction temperature relationship curve is obtained by fitting. Obtain the rated operating current, and based on the rated operating current and the current-junction temperature relationship curve, obtain the target junction temperature; Historical junction temperature data is acquired, and the LED chips are sorted based on the historical junction temperature data and the target junction temperature.

2. The junction temperature testing and sorting method according to claim 1, characterized in that, The steps for calibrating the voltage temperature sensitivity coefficient of the LED chip include: Obtain the first calibration temperature, the second calibration temperature, and the calibration current; The LED chip is placed in a constant temperature oven, the constant temperature oven is stabilized at the first calibrated temperature, and the calibrated current is applied to the LED chip to obtain the first positive voltage. The constant temperature oven is stabilized at the second calibrated temperature, and the calibrated current is applied to the LED chip to obtain the second positive voltage; The voltage temperature sensitivity coefficient is calculated based on the first positive voltage, the second positive voltage, the first calibration temperature, and the second calibration temperature.

3. The junction temperature testing and sorting method according to claim 2, characterized in that, The rated current range is 0.05mA to 0.1mA.

4. The junction temperature testing and sorting method according to claim 1, characterized in that, The test parameter set includes several test current coefficients and steady-state times. The step of performing several transient voltage tests and several steady-state voltage tests on the LED chip at the test ambient temperature based on the basic test current value and the test parameter set to obtain several test transient voltage values ​​and several test steady-state voltage values ​​includes: Based on the aforementioned basic value of the test current and several of the aforementioned test current coefficients, several test currents are calculated. The LED chip is subjected to the test current at the test ambient temperature to obtain the test transient voltage value; Based on the steady-state time, the steady-state time point of the LED chip is determined, and when the steady-state time point is reached, the test steady-state voltage value is obtained.

5. The junction temperature testing and sorting method according to claim 1, characterized in that, The step of obtaining several junction temperatures based on the voltage temperature sensitivity coefficient, the test environment temperature, several transient test voltage values, and several steady-state test voltage values ​​includes: The voltage difference is calculated based on the test steady-state voltage value and the test transient voltage value; The temperature rise value is calculated based on the voltage difference and the voltage temperature sensitivity coefficient. The junction temperature is calculated based on the temperature rise and the ambient temperature of the test environment.

6. The junction temperature testing and sorting method according to claim 4, characterized in that, The step of fitting a current-junction temperature relationship curve based on the baseline test current value, the test parameter set, and several junction temperatures includes: Using the test current as the abscissa value and the junction temperature as the ordinate value, a curve fitting point is established; The current-junction temperature relationship curve is obtained by fitting several of the aforementioned fitting points.

7. The junction temperature testing and sorting method according to claim 1, characterized in that, The step of acquiring historical junction temperature data and sorting the LED chips based on the historical junction temperature data and the target junction temperature includes: Several application scenarios are obtained, and several junction temperature ranges are determined based on the historical junction temperature data and the several application scenarios; A junction temperature threshold is determined based on the historical junction temperature data. If the target junction temperature is greater than or equal to the junction temperature threshold, the LED chip is scrapped. If the target junction temperature is less than the junction temperature threshold, the junction temperature range into which the target junction temperature falls is determined, so as to sort the LED chips.

8. A junction temperature testing and sorting system, employing the junction temperature testing and sorting method as described in any one of claims 1 to 7, characterized in that, The system includes: The calibration module is used to calibrate the voltage-temperature sensitivity coefficient of the LED chip. The testing module is used to set the test environment temperature, obtain the basic value of the test current and the test parameter set, and perform several transient voltage tests and several steady-state voltage tests on the LED chip at the test environment temperature based on the basic value of the test current and the test parameter set, so as to obtain several test transient voltage values ​​and several test steady-state voltage values. The calculation module is used to obtain several junction temperatures based on the voltage temperature sensitivity coefficient, the test environment temperature, several test transient voltage values, and several test steady-state voltage values; The fitting module is used to fit a current-junction temperature relationship curve based on the basic value of the test current, the set of test parameters, and several junction temperatures. The result module is used to obtain the rated operating current and, based on the rated operating current and the current-junction temperature relationship curve, to obtain the target junction temperature. The sorting module is used to acquire historical junction temperature data and sort the LED chips based on the historical junction temperature data and the target junction temperature.

9. A computer comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the junction temperature testing and sorting method as described in any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the junction temperature testing and sorting method as described in any one of claims 1 to 7.

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