Micro-led electrical detection structure, electrical detection system and detection method

Abstract

The application relates to an electrical detection structure, an electrical detection system and a detection method for a Micro-LED, wherein the electrical detection structure comprises a to-be-detected silicon wafer and a detection silicon wafer, the to-be-detected silicon wafer contains a plurality of arrayed to-be-detected Micro-LED chips; the detection silicon wafer is bonded and solidifiedly connected with the to-be-detected silicon wafer, the detection silicon wafer is provided with a pre-etched power supply circuit, the power supply circuit is used for parallel connection of the Micro-LED chips on the to-be-detected silicon wafer, the detection silicon wafer is further provided with a first electrode power supply point and a second electrode power supply point, and the polarity of the first electrode power supply point is opposite to that of the second electrode power supply point. The electrical detection structure can realize unified light emission of all the Micro-LED chips on the to-be-detected silicon wafer, helps to improve the detection efficiency, can improve the accuracy and reliability of the detection result, and can avoid the situation that the detected chips cannot be lighted when actually used on a backboard, thereby improving the success rate of backboard lighting and the production yield of the chips.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to electrical testing structures, electrical testing systems and testing methods for Micro-LEDs. Background Technology

[0002] Micro-LED boasts advantages such as high brightness, long lifespan, fast response, and high contrast, making it a rapidly emerging display technology. However, due to batch-to-batch performance variations in incoming LED materials during production, it is necessary to test the brightness, color, and other aspects of the incoming LED materials to ensure a high yield rate for Micro-LED manufacturing.

[0003] In related technologies, PL (Photoluminescence) and AOI (Automated Optical Inspection) technologies are commonly used to inspect incoming LED materials. Incoming LED materials are silicon wafers containing multiple Micro-LED chips. When inspecting the performance of Micro-LED chips, PL technology uses light to excite the LED and analyzes its emitted light spectrum to determine its quality based on the chip's luminance and chromaticity. AOI technology, on the other hand, directly detects surface defects in the chip through image analysis to determine its quality. However, while PL and AOI technologies provide a certain level of quality control, there is a problem where the test results do not match the actual electrical performance of the chip. This can lead to the inspected Micro-LED chips failing to light up when actually used on a backplane, resulting in a lower success rate for backplane LED illumination. Summary of the Invention

[0004] Therefore, it is necessary to address the technical problem that the performance testing methods for Micro-LED chips in related technologies lead to a decrease in the success rate of backplane lighting, and to provide a Micro-LED electrical performance testing structure, electrical testing system, and testing method.

[0005] In a first aspect, this application provides a Micro-LED electrical performance detection structure, comprising:

[0006] The silicon wafer to be tested contains multiple arrays of Micro-LED chips to be tested;

[0007] The testing silicon wafer is bonded and solidified to the silicon wafer to be tested. The testing silicon wafer has pre-etched power lines, which are used to connect the Micro-LED chips on the silicon wafer to be tested in parallel. The testing silicon wafer also has a first electrode power point and a second electrode power point, with the polarity of the first electrode power point being opposite to that of the second electrode power point.

[0008] In one embodiment, the silicon wafer for testing is further provided with an alignment portion, which is used to assist in the alignment of the silicon wafer to be tested and the silicon wafer for testing during bonding and curing.

[0009] In one embodiment, the contact area between the silicon wafer to be tested and the silicon wafer used for testing is cured with organic adhesive.

[0010] Secondly, this application provides an electrical testing system, including any of the electrical testing structures for Micro-LEDs provided in the first aspect. The electrical testing system further includes a chip performance testing component, which is used to determine the brightness and chromaticity of the silicon wafer under test when it emits light based on the acquired image of the silicon wafer under test emitting light, and to determine the defective LEDs based on the brightness, and to determine the classification level of each Micro-LED chip based on the chromaticity.

[0011] In one embodiment, the chip performance testing component includes an image acquisition unit, a spectral detection unit, and a controller. The image acquisition unit is used to acquire an image of the silicon wafer under test emitting light and transmit the image to the controller. The spectral detection unit is used to detect the chromaticity of each Micro-LED chip emitting light and transmit each chromaticity to the controller. The controller is used to determine the brightness of each Micro-LED chip and the number of defective LEDs based on the image. The controller is also used to determine the classification level of the Micro-LED chip based on the chromaticity of the emitted light.

[0012] In one embodiment, the controller determines that Micro-LED chips whose brightness is not greater than the preset brightness threshold are defective LEDs based on the comparison result between the brightness of each Micro-LED chip and the preset brightness threshold. The controller determines the classification level of each Micro-LED chip based on the chromaticity of each Micro-LED chip when it emits light and a preset mapping table between chromaticity and classification level.

[0013] Thirdly, this application provides a detection method applied to any of the electrical detection systems provided in the second aspect, the detection method comprising the following steps:

[0014] The silicon wafer to be tested is bonded and solidified with the silicon wafer for testing, and the first electrode power-on point and the second electrode power-on point of the silicon wafer for testing are energized. The silicon wafer for testing is provided with power-on lines that connect each Micro-LED chip in parallel.

[0015] The chip performance testing component uses images of the silicon wafer under test emitting light to determine the brightness and chromaticity of each Micro-LED chip. Based on the brightness, it identifies defective LEDs, and based on the chromaticity, it determines the classification level of the Micro-LED chips.

[0016] In one embodiment, the chip performance testing component includes a controller that determines defective LEDs based on brightness and classifies the Micro-LED chip based on chromaticity, including:

[0017] The controller compares the brightness of each Micro-LED chip with the preset brightness threshold and determines that Micro-LED chips whose brightness is not greater than the preset brightness threshold are defective LEDs.

[0018] The controller obtains a preset mapping table between chroma and classification level, and then searches the mapping table to determine the classification level corresponding to the chroma.

[0019] In one embodiment, bonding and curing the silicon wafer to be tested and the silicon wafer for testing includes:

[0020] After aligning the silicon wafer to be tested with the silicon wafer used for testing, they are bonded and cured using organic adhesive.

[0021] In one embodiment, after determining the defective LEDs based on brightness and the classification level of the Micro-LED chip based on chromaticity, the detection method further includes:

[0022] The bonded organic adhesive is separated from the silicon wafer to be tested by ultrasonic cleaning.

[0023] The aforementioned Micro-LED electrical testing structure includes a silicon wafer to be tested and a testing silicon wafer. The silicon wafer to be tested contains multiple arrayed Micro-LED chips to be tested. The testing silicon wafer is bonded and solidified to the silicon wafer to be tested. The testing silicon wafer has pre-etched power lines, which are used to connect the Micro-LED chips on the silicon wafer to be tested in parallel. The testing silicon wafer also has a first electrode power-on point and a second electrode power-on point, the polarity of which is opposite to that of the second electrode power-on point. This application establishes specific power lines on a testing silicon wafer and bonds and solidifies the testing silicon wafer with the silicon wafer under test, allowing all Micro-LED chips on the silicon wafer under test to be connected in parallel. During testing, when the testing silicon wafer is energized, all Micro-LED chips on the silicon wafer under test can be simultaneously illuminated, enabling electrical testing of the Micro-LEDs. Furthermore, when performing performance testing on Micro-LED chips based on this electrical testing structure, compared to traditional PL testing and AOI testing technologies, it ensures that the test results match the actual electrical performance of the chip, thus preventing the tested chip from failing to light up during actual use on the backplane and improving the success rate of backplane LED illumination. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of the silicon wafer to be tested in some embodiments of this application;

[0026] Figure 2 This is a schematic diagram of the structure of the silicon wafer used for detection in some embodiments of this application;

[0027] Figure 3 This is a schematic diagram illustrating the structure of the silicon wafer to be tested and the silicon wafer for testing after bonding and curing in some embodiments of this application.

[0028] Explanation of icon numbers:

[0029] 100. Silicon wafer to be tested; 110. Micro-LED chip; 200. Silicon wafer for testing; 210. First electrode energizing point; 220. Second electrode energizing point. Detailed Implementation

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0031] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," "vertical," and "horizontal," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0032] 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 indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two elements or the interaction between two elements, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. It should be noted that when an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intervening element present.

[0034] Micro-LED boasts advantages such as high brightness, long lifespan, fast response, and high contrast, making it a rapidly emerging display technology. Due to batch-to-batch performance variations in incoming LED materials during production, brightness and colorimetry testing is necessary to ensure high yield rates for Micro-LEDs. Furthermore, in Micro-LED display technology, the backplane refers to the substrate that supports the Micro-LED chips and provides electrical connections. The backplane is not merely a supporting structure; it also transmits power to each individual Micro-LED chip, enabling it to emit light.

[0035] In related technologies, PL (Photoluminescence) and AOI (Automated Optical Inspection) technologies are commonly used to inspect incoming LED materials. Incoming LED materials are silicon wafers containing multiple Micro-LED chips. When inspecting the performance of Micro-LED chips, PL technology uses light to excite the LED and analyzes its emitted light spectrum to determine its quality based on the chip's luminance and chromaticity. AOI technology, on the other hand, directly detects surface defects in the chip through image analysis to determine its quality. However, while PL and AOI technologies provide a certain level of quality control, there is a problem where the test results do not match the actual electrical performance of the chip. This can lead to the inspected Micro-LED chips failing to light up when actually used on a backplane, resulting in a lower success rate for backplane LED illumination.

[0036] To address the technical problem that Micro-LED chip performance testing methods in related technologies lead to a decrease in the success rate of backplane LED illumination, firstly, referring to... Figure 1 and Figure 2 One embodiment of this application provides an electrical testing structure for Micro-LEDs, including a silicon wafer 100 to be tested and a testing silicon wafer 200. The silicon wafer 100 to be tested includes a plurality of Micro-LED chips 110 arranged in an array to be tested. The testing silicon wafer 200 is bonded and solidified to the silicon wafer 100 to be tested. The testing silicon wafer 200 is provided with pre-etched power lines, which are used to connect the Micro-LED chips 110 on the silicon wafer 100 to be tested in parallel. The testing silicon wafer 200 is also provided with a first electrode power-on point 210 and a second electrode power-on point 220. The polarity of the first electrode power-on point 210 is opposite to the polarity of the second electrode power-on point 220.

[0037] In this embodiment, the Micro-LED chips 110 on the silicon wafer 100 to be tested are arranged in a horizontal and vertical array, with equal distances between adjacent Micro-LED chips 110 on the left and right, and between adjacent Micro-LED chips 110 on the top and bottom. This ensures uniform pressure applied by the silicon wafer 200 to the silicon wafer 100 to be tested during subsequent bonding and curing, thus preventing excessive local pressure that could damage the chips. It also helps ensure the stability of the electrical connection between each Micro-LED chip 110 and the silicon wafer 200. The bonding method in this embodiment is either wire bonding or solder bonding. Wire bonding uses highly conductive metal wires to connect the electrodes of the Micro-LED chips 110 to the electrical lines of the silicon wafer 200 through methods such as thermoforming. Solder bonding uses solder to connect the electrodes of the Micro-LED chips 110 to the electrical lines of the silicon wafer 200. Curing is performed after bonding, using heating or other curing methods to ensure the bonding points or solder joints are strong, thereby guaranteeing the stability of the electrical connection.

[0038] The first electrode energizing point 210 is the P-terminal (positive terminal), which is also the positive voltage terminal that needs to be connected when powering the Micro-LED chip 110; the second electrode energizing point 220 is the N-terminal (negative terminal), which is also the negative voltage terminal that needs to be connected when powering the Micro-LED chip 110. When powering the detection silicon wafer 200, a constant voltage or current is supplied to the P-terminal, and the N-terminal is connected to the negative terminal of the power supply to ensure that the Micro-LED chip 110 lights up normally.

[0039] In this embodiment, by setting specific power lines on the detection silicon wafer 200 and bonding and solidifying the detection silicon wafer 200 with the silicon wafer 100 to be tested, all Micro-LED chips 110 on the silicon wafer 100 to be tested are connected in parallel. Thus, when the detection silicon wafer 200 is powered on during testing, all Micro-LED chips 110 on the silicon wafer 100 to be tested can be lit up uniformly, thereby realizing the electrical testing of Micro-LEDs. Moreover, when performing performance testing on Micro-LED chips 110 based on the electrical testing structure of this application, compared with traditional PL testing technology and AOI testing technology, it can ensure the degree of conformity between the test results and the actual electrical performance of the chip, thereby avoiding the situation where the tested chip cannot be lit up when actually used on the backplane, and thus improving the success rate of backplane lighting.

[0040] In some embodiments, the silicon wafer 200 for testing is further provided with an alignment portion, which is used to assist in the alignment of the silicon wafer 100 to be tested and the silicon wafer 200 for testing during bonding and curing.

[0041] The alignment part is an alignment mark. The alignment mark is used to improve the accuracy and efficiency of aligning the silicon wafer 100 to be tested with the silicon wafer 200 for testing, thereby ensuring the effect of subsequent bonding and curing of the silicon wafer 100 to be tested and the silicon wafer 200 for testing. The alignment mark can be a pattern, such as a cross or a circle.

[0042] Specifically, a photoresist pattern for alignment marking can be formed on the silicon wafer 200 for testing first, and then the silicon wafer 200 for testing can be etched by dry or wet etching processes to remove the silicon material under the photoresist, thereby forming an identifiable physical mark; alternatively, a contrast mark can be formed on the silicon wafer 200 for testing by printing, laser etching, or other methods.

[0043] In this embodiment, the alignment part helps to improve the alignment accuracy when the silicon wafer 100 to be tested and the silicon wafer 200 to be tested are bonded and cured, thereby helping to ensure the accuracy and reliability of subsequent electrical test results.

[0044] In some embodiments, the contact area between the silicon wafer 100 to be tested and the silicon wafer 200 for testing is cured with organic adhesive.

[0045] The organic adhesive is either a UV-curable adhesive or a thermosetting adhesive.

[0046] Specifically, uniformly coating the contact area between the silicon wafer 100 to be tested and the silicon wafer 200 for testing ensures a tight bond between them. In addition, the organic adhesive can also serve as a key medium for the electrical connection between each Micro-LED chip 110 and the silicon wafer 200 for testing. Furthermore, after the electrical test is completed, the bonded organic adhesive can be quickly removed by an ultrasonic cleaning device, allowing the silicon wafer 200 for testing to be reused, which helps reduce testing costs and ensures that the silicon wafer 100 to be tested and the silicon wafer 200 for testing will not be damaged when separated.

[0047] In summary, the Micro-LED electrical performance testing structure of this application has the following beneficial effects:

[0048] 1. By pre-setting specific power lines on the silicon wafer 200 for testing, the Micro-LED chips 110 are connected in parallel and then bonded together, so that all Micro-LED chips 110 are electrically connected on the silicon wafer. This makes the test results more consistent with the actual electrical performance of the chips compared with traditional PL testing and AOI testing technologies. This can avoid the situation where the tested chips cannot be lit when actually used on the backplane, thereby improving the success rate of backplane lighting. Moreover, compared with the traditional EL testing method (2s / ea), this application achieves uniform lighting of all Micro-LED chips 110 through pre-setting specific power lines, which helps to improve the chip testing efficiency.

[0049] 2. By bonding and curing the silicon wafer 100 to be tested and the silicon wafer 200 for testing with organic adhesive, external damage to the Micro-LED can be avoided compared with the traditional EL probe method; and the cost of the silicon wafer 200 for testing is lower than that of the EL probe.

[0050] 3. Compared with the test data obtained by traditional PL technology, the test data obtained by the electrical test through the above-mentioned electrical test structure is closer to the data of the real backplane, thus making the performance test results of Micro-LED chip 110 more reliable.

[0051] Secondly, one embodiment of this application provides an electrical testing system applied to any of the electrical testing structures for Micro-LEDs provided in the first aspect above. The electrical testing system further includes a chip performance testing component, which is used to determine the brightness and chromaticity of the silicon wafer under test when it emits light based on the acquired image of the silicon wafer under test emitting light, and to determine the defective LEDs based on the brightness, and to determine the classification level of each Micro-LED chip based on the chromaticity.

[0052] The classification level refers to categorizing the tested Micro-LED chips into different grades based on measurement results. This is done to ensure that Micro-LED chips with the same brightness and color gamut are assigned to the same area during subsequent assembly, achieving optimal display performance. Defective LEDs include Micro-LEDs that are short-circuited, open-circuited, or have insufficient brightness.

[0053] Specifically, by performing electrical tests on the aforementioned Micro-LED electrical testing structure using chip performance testing components, the accuracy and reliability of determining the classification level of defective LEDs and each Micro-LED chip can be improved, thereby increasing the success rate of backplane lighting and ensuring the production yield of Micro-LED chips.

[0054] In some embodiments, the chip performance testing component includes an image acquisition unit, a spectral detection unit, and a controller. The image acquisition unit is used to acquire an image of the silicon wafer under test emitting light and transmit the image to the controller. The spectral detection unit is used to detect the chromaticity of each Micro-LED chip emitting light and transmit each chromaticity to the controller. The controller is used to determine the brightness and defective LEDs of each Micro-LED chip based on the image. The controller is also used to determine the classification level of the Micro-LED chip based on the emitting chromaticity.

[0055] The image acquisition device is a high-resolution and high-sensitivity camera, and the spectral detection device is a spectrometer. The spectrometer is used to analyze the spectral characteristics of LED chip emission. The camera, spectrometer, and controller are connected together.

[0056] Specifically, after the Micro-LED chips on the silicon wafer to be tested are lit, an image of the Micro-LED chips emitting light is captured by a camera, and the brightness of each Micro-LED chip is analyzed by the image processing software loaded in the controller to determine the luminous intensity and defective LEDs. In addition, the spectral characteristics of the light emitted by the Micro-LED chips are analyzed by a spectrometer, and the controller determines the colorimetry of the chips and their corresponding classification level. For example, some chips emit cool white light and are classified as cool white light, while some chips emit warm white light and are classified as warm white light.

[0057] In this embodiment, the combination of the controller, camera, and spectrometer helps to accurately determine the classification level of defective LEDs and each Micro-LED chip, thereby improving the success rate of backplane lighting and ensuring the production yield of Micro-LED chips.

[0058] In some embodiments, the controller determines that Micro-LED chips with brightness not greater than the preset brightness threshold are defective LEDs based on the comparison result between the brightness of each Micro-LED chip and the preset brightness threshold. The controller determines the classification level of each Micro-LED chip based on the chromaticity of each Micro-LED chip when it emits light and a preset mapping table between chromaticity and classification level.

[0059] Specifically, the preset brightness threshold is set according to the design requirements of the chips in this production batch. When the brightness of a chip is greater than the preset brightness threshold, it indicates that the chip's luminous intensity is qualified; conversely, if the brightness of a chip is not greater than the preset brightness threshold, it indicates that the chip's luminous intensity is unqualified, and it can be identified as a defective LED. The preset mapping table between chromaticity and classification level is also set according to the design requirements of the chips in this production batch. This mapping table can help quickly determine the classification level corresponding to the detected chromaticity.

[0060] Thirdly, one embodiment of this application provides a detection method applied to any of the electrical detection systems provided in the second aspect above. The detection method includes the following steps:

[0061] The silicon wafer to be tested is bonded and solidified with the silicon wafer for testing, and the first electrode power-on point and the second electrode power-on point of the silicon wafer for testing are energized. The silicon wafer for testing is provided with power-on lines that connect each Micro-LED chip in parallel.

[0062] The chip performance testing component uses images of the silicon wafer under test emitting light to determine the brightness and chromaticity of each Micro-LED chip. Based on the brightness, it identifies defective LEDs, and based on the chromaticity, it determines the classification level of the Micro-LED chips.

[0063] In some embodiments, the chip performance testing component includes a controller that determines defective LEDs based on brightness and classifies Micro-LED chips based on chromaticity, including:

[0064] The controller compares the brightness of each Micro-LED chip with the preset brightness threshold and determines that Micro-LED chips whose brightness is not greater than the preset brightness threshold are defective LEDs.

[0065] The controller obtains a preset mapping table between chroma and classification level, and then searches the mapping table to determine the classification level corresponding to the chroma.

[0066] In some embodiments, bonding and curing the silicon wafer to be tested to the silicon wafer for testing includes:

[0067] After aligning the silicon wafer to be tested with the silicon wafer used for testing, they are bonded and cured using organic adhesive.

[0068] In some embodiments, after determining the defective LEDs based on brightness and the classification level of the Micro-LED chip based on chromaticity, the detection method further includes:

[0069] The bonded organic adhesive is separated from the silicon wafer to be tested by ultrasonic cleaning.

[0070] Specifically, after completing the electrical testing, the bonded organic materials are removed through ultrasonic cleaning, which facilitates the rapid separation of the chip from the testing silicon wafer. This step ensures that the chip is not damaged during separation, and the testing silicon wafer can be reused, thereby reducing production costs.

[0071] In one detailed embodiment, the detection method of this application includes the following steps:

[0072] Specific electrical lines are etched on the silicon wafer for testing, so that all the Micro-LED chips on the silicon wafer to be tested are connected in parallel, and alignment marks are formed on the silicon wafer for testing by laser engraving.

[0073] According to the comparison mark, align the silicon wafer to be tested with the silicon wafer used for testing, and use organic adhesive and its corresponding curing method to bond and cure the silicon wafer to be tested and the silicon wafer used for testing.

[0074] The detection silicon wafer is powered by the first electrode energizing point and the second electrode energizing point, and a constant current or constant voltage is provided.

[0075] The system uses a camera to capture images of the Micro-LED chip emitting light, analyzes the spectral characteristics of the light emitted by the Micro-LED chip using a spectrometer, and outputs the image data and spectral characteristic data to the controller.

[0076] The controller identifies images and analyzes spectral characteristics to determine the brightness and chromaticity of each Micro-LED chip. Micro-LED chips with brightness not exceeding a preset brightness threshold are identified as defective LEDs. The classification level of each Micro-LED chip is determined according to a preset mapping table between chromaticity and classification level.

[0077] Ultrasonic cleaning equipment is used to remove the bonded organic adhesive, thereby separating the silicon wafer to be tested from the silicon wafer used for testing.

[0078] The detection method in this application achieves unified illumination of all Micro-LED chips on the silicon wafer under test by aligning and bonding the silicon wafer to be tested and providing constant current or constant voltage to the silicon wafer for testing, thereby improving detection efficiency. Furthermore, the detection results obtained by this method are closer to the actual backplane conditions. In other words, compared to traditional PL and AOI detection technologies, this method improves the accuracy and reliability of the detection results, thus avoiding situations where the tested chips fail to light up during actual use on the backplane, thereby increasing the success rate of backplane illumination and chip production yield. In addition, by using organic adhesive bonding and curing, the silicon wafer under test and the silicon wafer for testing can be separated by ultrasonic cleaning after electrical testing, enabling the reuse of the silicon wafer for testing and thus helping to reduce costs.

[0079] In the description of this specification, references to terms such as "some embodiments," "other embodiments," 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 this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0080] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A Micro-LED electrical performance testing structure, characterized in that, The Micro-LED electrical performance detection structure includes: The silicon wafer to be tested contains multiple arrays of Micro-LED chips to be tested; The testing silicon wafer is bonded and solidified to the silicon wafer to be tested. The testing silicon wafer has pre-etched power lines, which are used to connect the Micro-LED chips on the silicon wafer to be tested in parallel. The testing silicon wafer also has a first electrode power point and a second electrode power point, the polarity of the first electrode power point being opposite to the polarity of the second electrode power point.

2. The Micro-LED electrical performance testing structure according to claim 1, characterized in that, The silicon wafer used for testing is also provided with an alignment portion, which is used to assist in the alignment of the silicon wafer to be tested and the silicon wafer used for testing during bonding and curing.

3. The Micro-LED electrical performance testing structure according to claim 1, characterized in that, The contact area between the silicon wafer to be tested and the silicon wafer used for testing is cured with organic adhesive.

4. An electrical detection system, characterized in that, The electrical testing structure for Micro-LEDs according to any one of claims 1-3 further includes a chip performance testing component, which is used to determine the brightness and chromaticity of the silicon wafer under test when it emits light based on the acquired image of the silicon wafer under test emitting light, and to determine the defective LEDs based on the brightness, and to determine the classification level of each Micro-LED chip based on the chromaticity.

5. The electrical detection system according to claim 4, characterized in that, The chip performance testing component includes an image acquisition unit, a spectral detection unit, and a controller. The image acquisition unit is used to acquire an image of the silicon wafer under test emitting light and transmit the image to the controller. The spectral detection unit is used to detect the chromaticity of each Micro-LED chip emitting light and transmit each chromaticity to the controller. The controller is used to determine the brightness of each Micro-LED chip and the defective LEDs based on the image. The controller is also used to determine the classification level of the Micro-LED chip based on the chromaticity of the emitted light.

6. The electrical detection system according to claim 5, characterized in that, The controller determines that the Micro-LED chip whose brightness is not greater than the preset brightness threshold is the defective LED based on the comparison result between the brightness of each Micro-LED chip and the preset brightness threshold. The controller determines the classification level of each Micro-LED chip based on the chromaticity of each Micro-LED chip when it emits light and the preset mapping relationship table between chromaticity and classification level.

7. A detection method, characterized in that, The electrical detection system applied to any one of claims 4-6, the detection method comprising the following steps: The silicon wafer to be tested is bonded and cured with the silicon wafer for testing, and the first electrode power-on point and the second electrode power-on point of the silicon wafer for testing are energized. The silicon wafer for testing is provided with power-on lines that connect each Micro-LED chip in parallel. Using a chip performance testing component, the brightness and chromaticity of each Micro-LED chip are determined based on the acquired image of the silicon wafer under test emitting light. Defective LEDs are identified based on the brightness, and the classification level of the Micro-LED chip is determined based on the chromaticity.

8. The detection method according to claim 7, characterized in that, The chip performance testing component includes a controller, and the steps of determining defective LEDs based on the brightness and determining the classification level of the Micro-LED chip based on the chromaticity include: The controller compares the brightness of each Micro-LED chip with a preset brightness threshold and determines the Micro-LED chip whose brightness is not greater than the preset brightness threshold as the defective LED. The controller obtains a preset mapping table between chroma and classification level, and searches the mapping table to determine the classification level corresponding to the chroma.

9. The detection method according to claim 7, characterized in that, The bonding and curing process between the silicon wafer to be tested and the silicon wafer for testing includes: After aligning the silicon wafer to be tested with the silicon wafer for testing, they are bonded and cured using organic adhesive.

10. The detection method according to claim 9, characterized in that, After determining the defective LEDs based on the brightness and the classification level of the Micro-LED chip based on the chromaticity, the method further includes: The bonded organic adhesive is separated by ultrasonic cleaning.

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