Testable micro-device arrangement structure and its manufacturing method and testing method

Abstract

The present application provides a testable micro-device arrangement structure and a manufacturing method and a testing method thereof, wherein the micro-device arrangement structure comprises a substrate, a plurality of micro-LED chips arranged in an array on the substrate, a first electrode and a second electrode on the micro-LED chip located on a side away from the substrate, and an extended electrode electrically connected to the first electrode and / or the second electrode of the micro-LED chip, wherein the extended electrode has a large area, and one extended electrode is electrically connected to the electrodes of 2-4 micro-LED chips at the same time. Due to the large area of ​​the extended electrode, the micro-LED chip can be tested for photoelectric performance using a probe; and the extended electrode is connected to the electrodes of 2-4 micro-LED chips at the same time, so that during the test, the number of probe movements can be reduced relative to the number of probe movements for testing one by one, thereby saving test time; and at the same time, avoiding test errors caused by bad points when connected in series or in parallel, thereby improving the accuracy of the test.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor device manufacturing, and in particular to a testable micro-device arrangement structure and a manufacturing method and a testing method thereof. Background Art

[0002] LED (Light-Emitting Diode) chips are the core components of semiconductor lighting. Ensuring their basic optoelectronic performance and appearance requirements is the basis for subsequent processing. After the production and processing of LED chips is completed, the chips need to be tested for optoelectronic performance in order to classify the LED chips according to their optoelectronic parameters.

[0003] In existing LED chips, automatic test machines are generally used for testing, but the spot testing technology in the existing technology is usually suitable for ordinary-sized LED chips. With the development of LED, MiniLED and MicroLED are the next-generation display technologies. By miniaturizing LED chips, they are used as display panels. However, the probes on the automatic test machines in the existing technology cannot perform photoelectric testing on MiniLED and MicroLED micro devices.

[0004] The existing technology uses electrode strips to lead out the chip electrodes as a whole, so that multiple LED chips are connected in parallel or in series, batch testing, and collecting photoelectric data of array chips, but the detection accuracy is low. Leading out large electrodes one by one and using probes to test the chips one by one according to the traditional method will occupy more effective area of ​​the wafer, and because the number of chips on a wafer is very large, this will undoubtedly take a lot of time.

[0005] Therefore, how to provide a structure and testing method suitable for the detection of optoelectronic properties of micro devices that can achieve a compromise between detection accuracy and test time and occupies a small effective area has become an urgent problem to be solved. Summary of the invention

[0006] In view of this, the present invention provides a testable micro-device arrangement structure and its manufacturing method and testing method to solve the problems in the prior art that batch testing of micro-devices is efficient but low in accuracy, and testing of micro-devices one by one is accurate but low in efficiency and occupies a large effective area.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A testable micro-device arrangement structure, comprising:

[0009] substrate;

[0010] A plurality of micro LED chips arranged in an array on the substrate, each of the micro LED chips comprising a first electrode and a second electrode, the first electrode and the second electrode both being located on a side of the micro LED chip structure away from the substrate;

[0011] an extended electrode located on a side of the first electrode and the second electrode facing away from the substrate, the extended electrode being used to be electrically connected to the first electrode and / or the second electrode;

[0012] Among them, one extended electrode is connected to the electrodes of 2-4 micro LED chips at the same time, and the area of ​​the extended electrode is larger than the sum of the electrode areas of the micro LED chips connected to it, so that when the micro LED chips are detected by using probes to electrically connect the two extended electrodes, every two probes can detect one micro LED chip separately.

[0013] Preferably, it also includes: a planarization layer and a barrier layer;

[0014] The planarization layer is located on the surface of the substrate, and its thickness is less than or equal to the thickness of the micro LED chip;

[0015] The barrier layer is located on the planarization layer and the micro LED chip, and exposes the first electrode and the second electrode of the micro LED chip.

[0016] Preferably, the extended electrode is located on a surface of the barrier layer facing away from the substrate.

[0017] Preferably, one extended electrode connects electrodes of two micro LED chips.

[0018] Preferably, each column of the plurality of micro LED chips arranged in an array comprises: a first micro LED chip and a second micro LED chip which are repeatedly arranged in sequence;

[0019] In the same column, the first electrode of the first micro LED chip and the first electrode of the second micro LED chip located therebelow are connected to the same extended electrode;

[0020] The second electrode of the second micro LED chip and the second electrode of the first micro LED chip located therebelow are connected to the same extended electrode.

[0021] Preferably, in the same row, the first electrode of each micro LED chip and the second electrode of the micro LED chip adjacent thereto are connected to the same extended electrode.

[0022] Preferably, one extended electrode connects electrodes of three micro LED chips;

[0023] Each column of the plurality of micro LED chips arranged in an array includes: a third micro LED chip, a fourth micro LED chip and a fifth micro LED chip which are repeatedly arranged in sequence;

[0024] The first electrode of the third micro LED chip in the i-th column and the second electrodes of the third micro LED chip and the fourth micro LED chip in the i-1-th column are connected to the same extended electrode;

[0025] The second electrodes of the third micro LED chip and the fourth micro LED chip in the i-th column and the first electrode of the third micro LED chip in the (i+1)-th column are connected to the same extended electrode;

[0026] The first electrodes of the fourth micro LED chip and the fifth micro LED chip in the i-th column and the second electrode of the fifth micro LED chip in the i-1-th column are connected to the same extended electrode;

[0027] The second electrode of the fifth micro LED chip in the i-th column and the first electrodes of the fourth micro LED chip and the fifth micro LED chip in the (i+1)-th column are connected to the same extended electrode.

[0028] Preferably, one extended electrode connects electrodes of four micro LED chips;

[0029] Each column of the plurality of micro LED chips arranged in an array includes: a sixth micro LED chip and a seventh micro LED chip which are repeatedly arranged in sequence;

[0030] The first electrode of the sixth micro LED chip in the i-th column and the seventh micro LED chip therebelow and the second electrode of the sixth micro LED chip in the i-1-th column and the seventh micro LED chip therebelow are connected to the same extended electrode;

[0031] The second electrodes of the sixth micro LED chip in the i-th column and the seventh micro LED chip located thereover are connected to the same extended electrode as the first electrodes of the sixth micro LED chip in the i+1-th column and the seventh micro LED chip located thereover.

[0032] Preferably, the material of the blocking layer is photoresist, silicon dioxide, silicon nitride or polyimide.

[0033] The present invention also provides a method for manufacturing a testable micro-device arrangement structure, the method comprising:

[0034] providing a substrate;

[0035] A plurality of micro LED chips arranged in an array are fabricated on the substrate, each of the micro LED chips comprising a first electrode and a second electrode, wherein the first electrode and the second electrode are both located on a side of the micro LED chip structure away from the substrate;

[0036] forming a plurality of extended electrodes, wherein the extended electrodes are located on a side of the micro LED chip away from the substrate, and the extended electrodes are used to be electrically connected to the first electrode and / or the second electrode;

[0037] The area of ​​the extended electrode is greater than the sum of the areas of one of the first electrodes and one of the second electrodes, and one extended electrode is connected to electrodes of 2-4 micro LED chips at the same time.

[0038] Preferably, before forming a plurality of extended electrodes, the method further comprises:

[0039] forming a planarization layer, wherein the planarization layer is located between the plurality of micro LED chips, and the thickness of the planarization layer is less than or equal to the thickness of the micro LED chip;

[0040] A barrier layer is formed on the planarization layer, wherein a through hole is disposed on the barrier layer to expose the first electrode and the second electrode of the micro LED chip.

[0041] In addition, the present invention also provides a test method for a testable micro-device arrangement structure, based on the above testable micro-device arrangement structure in which the extended electrode is connected to two or four electrodes, the test method comprises:

[0042] providing a first probe and a second probe;

[0043] Along the column direction of the micro-device arrangement structure, applying the first probe to an extended electrode connected to a first electrode of a micro LED chip, and applying the second probe to an extended electrode connected to a second electrode of the micro LED chip;

[0044] Performing photoelectric parameter testing on the micro LED chip;

[0045] Moving the first probe to another extended electrode along the column direction, the other extended electrode and the extended electrode where the second probe is located form a loop for performing a photoelectric parameter test on another micro LED chip;

[0046] Then, along the column direction, the second probe is moved to another extended electrode, the further extended electrode and the extended electrode where the second probe is located form a loop for performing photoelectric parameter testing on another micro LED chip;

[0047] The first probe is repeatedly moved to another extended electrode, and the second probe is repeatedly moved to yet another extended electrode to complete the test of the micro-device arrangement structure.

[0048] A test method for a testable micro-device arrangement structure in which an extended electrode is simultaneously connected to three electrodes includes:

[0049] providing a third probe and a fourth probe;

[0050] Along the column direction of the micro-device arrangement structure, applying the third probe to an extended electrode connected to the first electrode of a third micro LED chip, and applying the fourth probe to an extended electrode connected to the second electrode of the third micro LED chip;

[0051] Performing a photoelectric parameter test on the third micro LED chip;

[0052] Move the third probe along the column direction to an extended electrode connected to the first electrode of a fourth micro LED chip located below the third micro LED chip, so that the extended electrode where the third probe is located and the extended electrode where the fourth probe is located form a loop for performing a photoelectric parameter test on the fourth micro LED chip;

[0053] Continue to move the fourth probe along the column direction to the extended electrode connected to the second electrode of the fifth micro LED chip located below the fourth micro LED chip, so that the extended electrode where the fourth probe is located and the extended electrode where the third probe is located form a loop for performing a photoelectric parameter test on the fifth micro LED chip;

[0054] Repeat the above steps in sequence to complete the test of the micro-device arrangement structure.

[0055] Through the above technical solutions, it can be known that the testable micro-device arrangement structure provided by the present invention includes a substrate, a plurality of micro LED chips arranged in an array on the substrate, a first electrode and a second electrode on the micro LED chip located on a side away from the substrate, and an extended electrode electrically connected to the first electrode and / or the second electrode of the micro LED chip, wherein the area of ​​the extended electrode is relatively large, and one extended electrode is electrically connected to the electrodes of 2-4 micro LED chips at the same time. Due to the large area of ​​the extended electrode, the micro LED chip can be tested for photoelectric performance using the probe of the existing test machine; and the extended electrode is connected to the electrodes of 2-4 micro LED chips at the same time, so that during the test process, the number of probe movements can be reduced relative to the number of probe movements for testing one by one, thereby saving test time; at the same time, since the extended electrode does not connect all micro LED chips in series or in parallel, during the test process, the micro LEDs are still tested one by one, avoiding test errors caused by bad pixels when using the series or parallel test method, thereby improving the test accuracy and obtaining the photoelectric data of all micro LEDs. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0057] Figure 1 A schematic top view of a testable micro-device arrangement structure provided by an embodiment of the present invention;

[0058] Figure 2 For along Figure 1 The cross-sectional view of line AA in the figure;

[0059] Figure 3 A top view of a testable micro-device arrangement structure provided by an embodiment of the present invention;

[0060] Figure 4-Figure 6 A schematic diagram of a testable photoelectric performance test process of a micro-device provided by an embodiment of the present invention;

[0061] Figure 7 A top view of another testable micro-device arrangement structure provided by an embodiment of the present invention;

[0062] Figure 8-Figure 11 The embodiment of the present invention provides Figure 1 Schematic diagram of the test process of the optoelectronic performance of the testable micro-device;

[0063] Fig.12 A schematic diagram of an arrangement structure of testable micro-devices after detection provided by an embodiment of the present invention;

[0064] Fig.13 A flow chart of a method for manufacturing a testable micro-device arrangement structure provided by an embodiment of the present invention;

[0065] Fig.14 A schematic cross-sectional structure diagram corresponding to one step of a testable micro-device arrangement structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0066] As described in the background technology section, when the probes on the automatic testing machine in the prior art perform photoelectric testing on the micro LED chip, there are either problems of low detection accuracy or problems of long testing time and large effective area occupation.

[0067] The inventors found that the root causes of the above problems are:

[0068] For microelectronic devices, since the electrodes are small, electrode strips are used to connect multiple LED chips in series or in parallel to achieve batch testing. However, when there is a bad spot, the LED chips connected to the entire electrode strip may not be lit, causing the entire LED chip strip to be unable to be tested. In fact, only one LED chip may be bad. Moreover, when testing an entire column or row of chips, higher or lower optical data of a single micro-LED will cause the optical data of the entire column of micro-LEDs to be higher or lower, resulting in lower detection accuracy.

[0069] Since the micro LED chips are closely arranged on the wafer, they can be called huge. Even if the probe can test the chips one by one according to the traditional method, on the one hand, the large number requires extremely high precision each time the probe is moved, resulting in a long time-consuming probe movement and alignment; on the other hand, the two positive and negative connected probes need to be moved each time, resulting in a large number of probe movements, which is also time-consuming. On the other hand, since the electrodes of micro LED chips are small, extended electrodes are usually required, but each electrode is provided with an electrode strip. In order to obtain the optoelectronic data of a single chip, the chip spacing will be expanded to leave space for the electrode strip, which significantly reduces the effective utilization of the wafer.

[0070] Based on this, the present invention provides a testable micro-device arrangement structure, comprising:

[0071] substrate;

[0072] A plurality of micro LED chips arranged in an array on the substrate, each of the micro LED chips comprising a first electrode and a second electrode, the first electrode and the second electrode both being located on a side of the micro LED chip structure away from the substrate;

[0073] an extended electrode located on a side of the first electrode and the second electrode facing away from the substrate, the extended electrode being used to be electrically connected to the first electrode and / or the second electrode;

[0074] Among them, one extended electrode is connected to the electrodes of 2-4 micro LED chips at the same time, and the area of ​​the extended electrode is larger than the sum of the electrode areas of the micro LED chips connected to it, so that when the micro LED chips are detected by using probes to electrically connect the two extended electrodes, every two probes can detect one micro LED chip separately.

[0075] The testable micro-device arrangement structure provided by the present invention comprises a substrate, a plurality of micro-LED chips arranged in an array on the substrate, a first electrode and a second electrode on the micro-LED chip located on a side away from the substrate, and an extended electrode electrically connected to the first electrode and / or the second electrode of the micro-LED chip, wherein the extended electrode has a large area, and one extended electrode is electrically connected to the electrodes of 2-4 micro-LED chips at the same time. Since the extended electrode has a large area, the micro-LED chip can be tested for photoelectric performance using the probe of an existing test machine; and since the extended electrode is connected to the electrodes of 2-4 micro-LED chips at the same time, the number of probe movement times during the test can be reduced relative to the number of probe movement times for testing one by one, thereby saving test time; at the same time, since the extended electrode does not connect all micro-LED chips in series or in parallel, the micro-LEDs are still tested one by one during the test, thereby avoiding test errors caused by bad points when connected in series or in parallel, thereby improving test accuracy.

[0076] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0077] See also Figure 1 and Figure 2 ,in, Figure 1 A schematic top view of a testable micro-device arrangement structure provided by an embodiment of the present invention; Figure 2 For along Figure 1 The cross-sectional view along the AA line in FIG. 2 , the testable micro-device arrangement structure comprises: a substrate 201; a plurality of micro LED chips 202 arranged in an array on the substrate 201, each micro LED chip comprising a first electrode 2031 and a second electrode 2032, the first electrode 2031 and the second electrode 2032 both being located on a side of the micro LED chip structure away from the substrate 201; an extended electrode (shown as 207 and 208) located on a side of the first electrode 2031 and the second electrode 2032 away from the substrate 201, the extended electrode being used to be electrically connected to the first electrode 2031 and / or the second electrode 2032; wherein the area of ​​the extended electrode is greater than the sum of the areas of one first electrode 2031 and one second electrode 2032, and one extended electrode is connected to electrodes of 2-4 micro LED chips at the same time.

[0078] In this embodiment, the substrate 201 is a growth substrate, and the material of the growth substrate is not limited, and the material may include sapphire, silicon wafer, silicon carbide, gallium arsenide, etc. The micro LED chip 202 may be a Micro-LED or Mini-LED chip, and the first electrode 2031 and the second electrode 2032 are metal electrodes.

[0079] It should be noted that this embodiment does not limit how the extended electrode is made and formed on the micro LED chip, as long as it can be achieved that one extended electrode is connected to 2-4 metal electrodes at the same time. Figure 2 As shown, the testable micro-device arrangement structure may also include a planarization layer 204 and a barrier layer 205, wherein the thickness of the planarization layer 204 is less than or equal to the thickness of the micro LED chip 202. In this embodiment, the function of the planarization layer 204 is to lay a foundation for the subsequent functional layer to avoid the breakage of the extended electrode due to the height difference. In this embodiment, the barrier layer 205 is located on the planarization layer 204 and is formed by coating. The barrier layer 205 is a photolithographic material, which may be a positive photoresist, a negative photoresist, silicon dioxide, silicon nitride or PI (polyimide) material. Through lithography, a through hole is formed to expose the first electrode 2031 and the second electrode 2032 of the micro LED chip 202. In this embodiment, the barrier layer 205 plays the role of insulation isolation.

[0080] It should be noted that the specific material and manufacturing method of the extended electrode are not limited in the present embodiment. Optionally, the extended electrode can be formed by a traditional evaporation process. According to the actual spacing between the micro LED chips, the spacing between the micro LED chips is fully utilized to deposit alkaline metal materials such as aluminum and indium to form the extended electrode. The specific area of ​​the extended electrode is not limited in the present embodiment. Optionally, the area of ​​the extended electrode can be 6-8 times the area of ​​the first electrode or the second electrode of the micro LED chip, which is suitable for the probe size on the test machine in the prior art, thereby reducing the accuracy requirements on the test machine when the probe moves.

[0081] It should be noted that the distribution of the extended electrodes (207 and 208) is not limited in this embodiment. The distribution of the extended electrodes can expand the electrodes of the micro LED chip during the test process, so that the area is increased to facilitate the probe testing. In addition, during the test process, when the probe is connected to the two extended electrodes to detect the micro LED chip, each two probes only detect one micro LED chip separately. That is, a positive probe and a negative probe, although both are connected to the extended electrodes, and one extended electrode is connected to the electrodes of multiple micro LED chips at the same time, only the positive and negative poles of one micro LED chip are turned on at a time, so that only one micro LED chip can be detected at a time.

[0082] Since the extended electrode is electrically connected to 2, 3 or 4 metal electrodes at the same time, compared with the single electrode extended electrode strip in the prior art, there is no need to set a large gap between each extended electrode and other adjacent extended electrodes, thereby relatively reducing the occupation of the effective area of ​​the wafer and improving the utilization rate of the wafer.

[0083] It should be noted that in this embodiment, the extended electrode is simultaneously connected to the electrodes of 2-4 micro LED chips, which means that the extended electrode is simultaneously connected to the single electrodes of 2, 3, or 4 micro LED chips, that is, it can simultaneously connect the first electrodes of two micro LED chips, or simultaneously connect the second electrodes of two micro LED chips, or simultaneously connect the first electrode of a micro LED chip and the second electrode of a micro LED chip, or simultaneously connect the first electrodes of two micro LED chips and the second electrode of a micro LED chip, or simultaneously connect the first electrodes of four micro LED chips, or simultaneously connect the second electrodes of four micro LED chips.

[0084] In order to conveniently explain the extended electrode distribution mode provided in the embodiment of the present invention, the embodiment of the present invention is explained in conjunction with the accompanying drawings. Figure 3 , Figure 3 A top view of a micro-device arrangement structure provided by an embodiment of the present invention; in this embodiment, an extended electrode is connected to electrodes of two micro LED chips at the same time, and multiple micro LED chips arranged in an array are repeatedly arranged. Each micro LED chip and other micro LED chips are made using the same process and are formed in the same manufacturing process. In order to distinguish the position of each micro LED chip and the connection relationship with other micro LED chips, in this embodiment, Figure 3 The connection relationship and arrangement of the micro LED chips in column B are the same as those of the micro LED chips in column B, and will not be described in detail in this embodiment.

[0085] See also Figure 3 , the same column includes the first micro LED chip 2021 and the second micro LED chip 2022 which are arranged repeatedly in sequence, that is, in the same column, there is a second micro LED chip 2022 between two adjacent first micro LED chips 2021, and there is a first micro LED chip 2021 between two second micro LED chips 2022. In the same row, there are either the first micro LED chip 2021 or the second micro LED chip 2022.

[0086] In this embodiment, the extended electrode includes a first extended electrode 207 connected to the first electrodes of the adjacent first micro LED chip 2021 and the second micro LED chip 2022 in the same column, and a second extended electrode 208 connected to the second electrodes of the adjacent second micro LED chip 2022 and the first micro LED chip 2021, wherein the first extended electrode 207 and the second extended electrode 208 differ by one micro LED chip in the column direction. Figure 3 As shown, the first extended electrode 207 is connected to the first electrode of the first micro LED chip 2021 in the j-th row of column B and the first electrode of the second micro LED chip 2022 in the j+1-th row; the second extended electrode 208 is simultaneously connected to the second micro LED chip 2022 in the j+1-th row of column B and the second electrode of the first micro LED chip 2021 in the j+2-th row, and so on, to form multiple repeating units, connecting all the micro LED chips on the wafer to the first extended electrode and the second extended electrode.

[0087] It should be noted that the polarities of the first electrode and the second electrode of the micro LED chip are not limited in this embodiment. Optionally, in the following embodiments, the first electrode is a positive electrode and the second electrode is a negative electrode.

[0088] In the case of the electrode distribution in which the extended electrode connects two micro LED chips, in this embodiment, when the photoelectric performance test of the micro LED chip is performed, the positive probe of the test machine is inserted into a first extended electrode, and the negative probe of the test machine is inserted into a second extended electrode connected to another metal electrode of the micro LED chip that is common to the metal electrode connected to the first extended electrode. Figure 4 As shown in , "+" and "-" signs are used to replace the probe positions; thus, the micro LED chip connected to the first extended electrode with the positive probe "+" and the second extended electrode with the negative probe "-" is tested, as shown in FIG. Figure 4 As shown in , the photoelectric performance test of the first micro LED chip is performed.

[0089] After testing the first micro LED chip, it is only necessary to follow the column direction, such as Figure 5 As shown, the negative probe "-" is moved toward the direction of the second micro LED chip connected to the first extended electrode with the positive probe "+". At this time, the negative probe "-" is inserted into the second extended electrode connected to the second electrode of the second micro LED chip, thereby testing the photoelectric performance of the second micro LED chip.

[0090] Then the second micro LED chip is tested, and only the column direction is required, such as Figure 6As shown, the positive probe "+" is moved toward the direction of the first micro LED chip connected to the second extended electrode with the negative probe "-". At this time, the positive probe "+" is inserted into the first extended electrode connected to the first electrode of the first micro LED chip, thereby testing the photoelectric performance of the first micro LED chip.

[0091] By analogy, the micro LED chip can be replaced by moving only one probe each time. There is no need to move two probes at the same time when testing the micro LED chips one by one as in the prior art. For testing the micro LED chips on a wafer, the probe movement time can be reduced by half, thereby saving the probe movement time and shortening the test time.

[0092] In another embodiment of the present invention, an extended electrode is connected to electrodes of two micro LED chips at the same time. Alternatively, in the same row, the first electrode of each micro LED chip and the second electrode of the adjacent micro LED chip are connected to the same extended electrode; the second electrode of each micro LED chip and the first electrode of the adjacent micro LED chip are connected to the same extended electrode. For example, a plurality of micro LED chips are included in the same row, and each micro LED chip has a first electrode on the left and a second electrode on the right. Then, the first electrode of each micro LED chip and the second electrode of the micro LED chip on its left are connected to an extended electrode at the same time. Then, the second electrode of the micro LED chip and the first electrode of the micro LED chip on its right are connected to an extended electrode at the same time. During detection, the positive and negative probes move along the row direction, which can also reduce the number of probe movement times.

[0093] In another embodiment of the present invention, see Figure 7 , Figure 7 A top view of a micro-device arrangement structure provided by an embodiment of the present invention; Figure 7 As shown in FIG. 1 , one extended electrode is connected to electrodes of three micro LED chips at the same time; in the same column, a third micro LED chip 2023, a fourth micro LED chip 2024 and a fifth micro LED chip 2025 are repeatedly arranged in sequence; wherein, please continue to refer to Figure 7, the first electrode of the third micro LED chip 2023 in the i-th column and the second electrodes of the third micro LED chip 2023 and the fourth micro LED chip 2024 in the i-1th column are connected to the same extended electrode 207; the second electrodes of the third micro LED chip 2023 and the fourth micro LED chip 2024 in the i-th column and the first electrode of the third micro LED chip 2023 in the i+1th column are connected to the same extended electrode 207; the first electrode of the fourth micro LED chip 2024 and the fifth micro LED chip 2025 in the i-1th column are connected to the same extended electrode 208; the second electrode of the fifth micro LED chip 2025 in the i-th column and the first electrode of the fourth micro LED chip 2024 and the fifth micro LED chip 2025 in the i+1th column are connected to the same extended electrode.

[0094] That is, every three electrodes of the six electrodes of the third micro LED chip, the fourth micro LED chip and the fifth micro LED chip are commonly connected to an extended electrode, so that the area of ​​the extended electrode is larger, and the accuracy of probe alignment can be reduced during the test process.

[0095] Referring to the above test method of connecting two electrodes to an extended electrode, the test method of connecting three electrodes to an extended electrode is not described in detail in this embodiment. Figure 7 As shown in , after testing the fifth micro LED chip, the negative probe "-" is moved upward by an extended electrode so that the fourth micro LED chip can be tested. Then the negative probe "-" is kept stationary, and the positive probe "+" is moved upward by an extended electrode to test the third micro LED chip.

[0096] It should be noted that the test method is different from the test method of connecting two electrodes to an extended electrode. Please continue to refer to Figure 7 In the embodiment of the present invention, after the fifth micro LED chip, the fourth micro LED chip and the third micro LED chip are detected in sequence, it is not necessary to move a single "+" probe or a "-" probe, but it is necessary to move the "+" probe and the "-" probe at the same time so that the two probes continue to form a loop. Although, compared with the test method in which two electrodes are connected to an extended electrode, there may be more probe movement times, but compared with the prior art in which the three micro LED chips are tested one by one, the test method provided by the embodiment of the present invention only requires the probe to be moved twice, thereby reducing the number of probe movement times to a certain extent, saving test time, and ensuring test accuracy. On the basis of the above, one extended electrode is connected to three electrodes, and compared with one extended electrode connected to one electrode, the number of extended electrodes is reduced, and the occupied wafer area is reduced, thereby avoiding occupying more effective area of ​​the wafer.

[0097] In another embodiment of the present invention, one extended electrode can also be connected to electrodes of four micro LED chips, such as Figure 1 As shown, it is a top view schematic diagram of another micro-device arrangement structure provided by an embodiment of the present invention; each column of multiple micro LED chips arranged in an array includes: a sixth micro LED chip 2026 and a seventh micro LED chip 2027 which are repeatedly arranged in sequence; wherein, the first electrode of the sixth micro LED chip 2026 in the i-th column and the seventh micro LED chip 2027 located below it and the second electrode of the sixth micro LED chip 2026 in the i-1-th column and the seventh micro LED chip 2027 located below it are connected to the same extended electrode 207; the second electrode 2027 of the sixth micro LED chip 2026 in the i-th column and the seventh micro LED chip located above it, and the first electrode of the sixth micro LED chip 2026 in the i+1-th column and the seventh micro LED chip 2027 located above it are connected to the same extended electrode.

[0098] Similar to an extended electrode connecting two micro LED chips, the difference is that the extended electrodes of two adjacent columns are merged into one extended electrode, thereby further reducing the number of extended electrodes. When two adjacent micro LED chips are connected to the same extended electrode, there is no need to set a gap between the two adjacent micro LED chips. That is, the effective area occupied when the gap between adjacent extended electrodes is set is reduced. Therefore, on the basis of ensuring the area of ​​the extended electrode for applying the probe, the area of ​​the wafer occupied by the extended electrode is further reduced, thereby improving the utilization rate of the effective area of ​​the wafer.

[0099] During the test, initially, the four probe positions are as follows Figure 8 As shown, the photoelectric data of the two chips can be collected at the same time, and then only the negative electrode probe is moved one step, as shown in Fig. 9 As shown, the photoelectric data of the next two chips are collected. Similarly, only the positive probe or the negative probe is moved one step to complete the chip test of all odd-numbered columns, that is, 50% of the chip data collection is completed. All four probes move one step to the left, such as Fig.10 As shown, start testing the chips in the even-numbered columns. Similarly, move the positive probe or the negative probe one step at a time. Fig.11 As shown in the figure, the test of all the chips in the even-numbered columns is completed. After a round of testing, the test of the entire wafer is completed.

[0100] It should be noted that after the test of the entire wafer is completed, the testable micro-device arrangement structure provided by the present invention has completed its mission. The extended electrode layer can be cleaned with an alkaline solution. The planarization layer 204 and the barrier layer 205 can also be cleaned with an organic cleaning agent, thereby the planarization layer, the barrier layer, and the conductive layer can all be cleaned. The wafer is restored to its original state, which is the same as a conventional wafer. Fig.12As shown, it can continue to be subjected to subsequent process operations such as cutting and sorting, which is perfectly integrated with today's production technology.

[0101] The micro-device arrangement structure provided by the embodiment of the present invention, firstly, adopts a technical solution that breaks through the traditional test method and makes the micro-device into a three-dimensional structure, that is, a layer of enlarged extended electrode is connected above the original electrode, and the extended electrode directly contacts the test probe without causing damage to the original electrode. The enlarged extended electrode greatly reduces the requirements for the machine, thereby reducing the equipment cost.

[0102] Secondly, the most important thing is that this structure can turn untestable tiny chips into testable ones, and can test small chips with critical electrodes or those that cannot be tested. Then, this technical solution only moves one probe at a time and only needs to consider the accuracy of one displacement to achieve the test of different micro LED chips, thus saving test time and reducing production costs.

[0103] Finally, the planarization layer, barrier layer, and conductive layer that play an auxiliary role can all be removed, fully connecting to the mature cutting production process without adding additional production difficulty and cost.

[0104] Moreover, the size of the expanded electrode is not affected by the chip spacing, and the utilization rate of the wafer can be maximized. The structure can eventually remove multiple layers of material by chemical methods without affecting the post-processing of the wafer. The existing technical solution is a two-dimensional structure, where the lead-out electrode and the chip are on the same plane, the utilization rate of the wafer is low, and all positive or negative electrodes in the array are led to the same large electrode. After the test is completed, the lead part cannot be removed independently, which will affect the post-processing.

[0105] Based on the same inventive concept, an embodiment of the present invention further provides a method for manufacturing a testable micro-device arrangement structure, which is used to manufacture the micro-device arrangement structure described in any one of the above embodiments. The method for manufacturing a micro-device arrangement structure is as follows: Fig.13 As shown, including:

[0106] S101: providing a substrate;

[0107] S102: forming a plurality of micro LED chips arranged in an array on the substrate, each of the micro LED chips comprising a first electrode and a second electrode, wherein the first electrode and the second electrode are both located on a side of the micro LED chip structure away from the substrate;

[0108] S103: forming a plurality of extended electrodes, wherein the extended electrodes are located on a side of the micro LED chip away from the substrate, and the extended electrodes are used to be electrically connected to the first electrode and / or the second electrode;

[0109] The area of ​​the extended electrode is greater than the sum of the areas of one of the first electrodes and one of the second electrodes, and one extended electrode is connected to electrodes of 2-4 micro LED chips at the same time.

[0110] It should be noted that the formation of multiple micro LED chips arranged in an array on a substrate can be made by using the process in the prior art, which is not described in detail in this embodiment. However, the process of forming multiple extended electrodes may include:

[0111] S104: forming a planarization layer, wherein the planarization layer is located between the plurality of micro LED chips, and the thickness of the planarization layer is less than or equal to the thickness of the micro LED chip;

[0112] S105: forming a barrier layer on the planarization layer, wherein the barrier layer is provided with a through hole 206 to expose the first electrode 2031 and the second electrode 2032 of the micro LED chip. Fig.14 shown.

[0113] Based on the same inventive concept, the present invention also provides a test method for a testable micro-device arrangement structure, based on the testable micro-device arrangement structure in which the extended electrode is simultaneously connected to two or four first electrodes or second electrodes, the test method comprising:

[0114] providing a first probe and a second probe;

[0115] Along the column direction of the micro-device arrangement structure, applying the first probe to an extended electrode connected to a first electrode of a micro LED chip, and applying the second probe to an extended electrode connected to a second electrode of the micro LED chip;

[0116] Performing photoelectric parameter testing on the micro LED chip;

[0117] Moving the first probe to another extended electrode along the column direction, the other extended electrode and the extended electrode where the second probe is located form a loop for performing a photoelectric parameter test on another micro LED chip;

[0118] Then, along the column direction, the second probe is moved to another extended electrode, the further extended electrode and the extended electrode where the second probe is located form a loop for performing photoelectric parameter testing on another micro LED chip;

[0119] The first probe is moved to another extended electrode, and the second probe is moved to yet another extended electrode repeatedly in sequence to complete the test of the micro-device arrangement structure.

[0120] In this embodiment, the probe moving path can be seen in Figure 4-Figure 6The steps shown are not described in detail in this embodiment. By moving a probe once, a micro LED chip can be tested, thereby reducing the number of probe movement times.

[0121] It should be noted that the test method specifically described in conjunction with the accompanying drawings has been clearly described in the above embodiments and will not be described in detail in this embodiment. You can directly refer to the test process of connecting the extended electrode to two micro LED chip electrodes and the test process of connecting the extended electrode to four micro LED chip electrodes in the previous embodiments. Regardless of the connection method, it can be achieved that one probe is moved to test one micro LED chip, thereby achieving one test of all micro LED chips one by one, improving the test accuracy, and moving the probe less times, saving test time.

[0122] In addition, for the method of connecting three electrodes to one extension electrode at the same time, see Figure 7 , the test method comprises:

[0123] providing a third probe and a fourth probe;

[0124] Along the column direction of the micro-device arrangement structure, applying the third probe to an extended electrode connected to the first electrode of a third micro LED chip, and applying the fourth probe to an extended electrode connected to the second electrode of the third micro LED chip;

[0125] Performing a photoelectric parameter test on the third micro LED chip;

[0126] Move the third probe along the column direction to an extended electrode connected to the first electrode of a fourth micro LED chip located below the third micro LED chip, so that the extended electrode where the third probe is located and the extended electrode where the fourth probe is located form a loop for performing a photoelectric parameter test on the fourth micro LED chip;

[0127] Continue to move the fourth probe along the column direction to the extended electrode connected to the second electrode of the fifth micro LED chip located below the fourth micro LED chip, so that the extended electrode where the fourth probe is located and the extended electrode where the third probe is located form a loop for performing a photoelectric parameter test on the fifth micro LED chip;

[0128] Repeat the above steps in sequence to complete the test of the micro-device arrangement structure.

[0129] That is, after detecting a combination of a third micro LED chip, a fourth micro LED chip and a fifth micro LED chip, the third probe and the fourth probe are moved at the same time so that the two probes are moved to another combination of a third micro LED chip, a fourth micro LED chip and a fifth micro LED chip at the same time, and the above steps are repeated.

[0130] In addition, it should be noted that the testing method provided in this embodiment can also start with the third probe and the fourth probe being connected to the extended electrode where the first electrode and the second electrode of the fifth micro LED chip are located, and then sequentially detecting the fourth micro LED chip and the third micro LED chip. The direction of the probe movement is not limited in this embodiment.

[0131] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0132] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that an article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such article or device. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the article or device including the above elements.

[0133] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A testable micro-device arrangement structure, characterized in that: include: substrate; A plurality of micro LED chips arranged in an array on the substrate, each of the micro LED chips comprising a first electrode and a second electrode, the first electrode and the second electrode both being located on a side of the micro LED chip structure away from the substrate; an extended electrode located on a side of the first electrode and the second electrode facing away from the substrate, the extended electrode being used to be electrically connected to the first electrode and / or the second electrode; A planarization layer and a barrier layer, wherein the planarization layer is located on the surface of the substrate, the barrier layer is located on the planarization layer and the micro LED chip, and the barrier layer exposes the first electrode and the second electrode of the micro LED chip, and the extended electrode is located on the surface of the barrier layer away from the substrate; One of the extended electrodes is connected to electrodes of 2-4 micro LED chips at the same time, and the area of ​​the extended electrode is larger than the sum of the electrode areas of the micro LED chips connected to it, so that when the micro LED chips are detected by using probes to electrically connect the two extended electrodes, each two probes can detect one micro LED chip separately.

2. The testable micro-device arrangement structure according to claim 1, characterized in that: Each column of the plurality of micro LED chips arranged in an array includes: a first micro LED chip and a second micro LED chip which are repeatedly arranged in sequence; In the same column, the first electrode of the first micro LED chip and the first electrode of the second micro LED chip located therebelow are connected to the same extended electrode; The second electrode of the second micro LED chip and the second electrode of the first micro LED chip located therebelow are connected to the same extended electrode.

3. The testable micro-device arrangement structure according to claim 1, characterized in that: In the same row, the first electrode of each micro LED chip and the second electrode of the micro LED chip adjacent thereto are connected to the same extended electrode.

4. The testable micro-device arrangement structure according to claim 1, characterized in that: An extended electrode connects electrodes of three micro-LED chips; Each column of the plurality of micro LED chips arranged in an array includes: a third micro LED chip, a fourth micro LED chip and a fifth micro LED chip which are repeatedly arranged in sequence; The first electrode of the third micro LED chip in the i-th column and the second electrodes of the third micro LED chip and the fourth micro LED chip in the i-1-th column are connected to the same extended electrode; The second electrodes of the third micro LED chip and the fourth micro LED chip in the i-th column and the first electrode of the third micro LED chip in the (i+1)-th column are connected to the same extended electrode; The first electrodes of the fourth micro LED chip and the fifth micro LED chip in the i-th column and the second electrode of the fifth micro LED chip in the i-1-th column are connected to the same extended electrode; The second electrode of the fifth micro LED chip in the i-th column and the first electrodes of the fourth micro LED chip and the fifth micro LED chip in the (i+1)-th column are connected to the same extended electrode.

5. The testable micro-device arrangement structure according to claim 1, characterized in that: An extended electrode connects electrodes of four micro-LED chips; Each column of the plurality of micro LED chips arranged in an array includes: a sixth micro LED chip and a seventh micro LED chip which are repeatedly arranged in sequence; The first electrode of the sixth micro LED chip in the i-th column and the seventh micro LED chip therebelow and the second electrode of the sixth micro LED chip in the i-1-th column and the seventh micro LED chip therebelow are connected to the same extended electrode; The second electrodes of the sixth micro LED chip in the i-th column and the seventh micro LED chip located thereover are connected to the same extended electrode as the first electrodes of the sixth micro LED chip in the i+1-th column and the seventh micro LED chip located thereover.

6. The testable micro-device arrangement structure according to claim 1, characterized in that: The material of the blocking layer is photoresist, silicon dioxide, silicon nitride or polyimide.

7. A method for manufacturing a testable micro-device arrangement structure, characterized in that: The micro-device arrangement structure manufacturing method comprises: providing a substrate; A plurality of micro LED chips arranged in an array are fabricated on the substrate, each of the micro LED chips comprising a first electrode and a second electrode, wherein the first electrode and the second electrode are both located on a side of the micro LED chip structure away from the substrate; forming a plurality of extended electrodes, wherein the extended electrodes are located on a side of the micro LED chip away from the substrate, and the extended electrodes are used to be electrically connected to the first electrode and / or the second electrode; The area of ​​the extended electrode is greater than the sum of the areas of one of the first electrodes and one of the second electrodes, and one extended electrode is connected to electrodes of 2-4 micro LED chips at the same time.

8. The method for manufacturing a testable micro-device arrangement structure according to claim 7, characterized in that: Before forming a plurality of extended electrodes, the method further includes: forming a planarization layer, wherein the planarization layer is located between the plurality of micro LED chips, and the thickness of the planarization layer is less than or equal to the thickness of the micro LED chip; A barrier layer is formed on the planarization layer, wherein a through hole is disposed on the barrier layer to expose the first electrode and the second electrode of the micro LED chip.

9. A method for testing a testable micro-device arrangement structure, characterized in that: Used to test the testable micro-device arrangement structure according to any one of claims 2, 3, and 5, the testing method comprising: providing a first probe and a second probe; Along the column direction of the micro-device arrangement structure, applying the first probe to an extended electrode connected to a first electrode of a micro LED chip, and applying the second probe to an extended electrode connected to a second electrode of the micro LED chip; Performing photoelectric parameter testing on the micro LED chip; Moving the first probe to another extended electrode along the column direction, the other extended electrode and the extended electrode where the second probe is located form a loop for performing a photoelectric parameter test on another micro LED chip; Then, along the column direction, the second probe is moved to another extended electrode, the further extended electrode and the extended electrode where the second probe is located form a loop for performing photoelectric parameter testing on another micro LED chip; The first probe is repeatedly moved to another extended electrode, and the second probe is repeatedly moved to yet another extended electrode to complete the test of the micro-device arrangement structure.

10. A method for testing a testable micro-device arrangement structure, characterized in that: Used to test the testable micro-device arrangement structure according to claim 4, the testing method comprising: providing a third probe and a fourth probe; Along the column direction of the micro-device arrangement structure, applying the third probe to an extended electrode connected to the first electrode of a third micro LED chip, and applying the fourth probe to an extended electrode connected to the second electrode of the third micro LED chip; Performing a photoelectric parameter test on the third micro LED chip; Move the third probe along the column direction to an extended electrode connected to the first electrode of a fourth micro LED chip located below the third micro LED chip, so that the extended electrode where the third probe is located and the extended electrode where the fourth probe is located form a loop for performing a photoelectric parameter test on the fourth micro LED chip; Continuing along the column direction, the fourth probe is moved to an extended electrode connected to the second electrode of a fifth micro LED chip located below the fourth micro LED chip, the extended electrode where the fourth probe is located and the extended electrode where the third probe is located form a loop for performing a photoelectric parameter test on the fifth micro LED chip; Apply the third probe to the extended electrode connected to the first electrode of the next third micro LED chip, and apply the fourth probe to the extended electrode connected to the second electrode of the next third micro LED chip, and repeat the process to complete the test of the micro device arrangement structure.

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