Growth substrate assembly, light emitting assembly, and method of making the same

Abstract

The present application relates to a kind of growth substrate assembly, light emitting component and its manufacturing method, growth substrate is equipped with several light emitting chips, the bottom surface of each light emitting chip is away from growth substrate and grows positive electrode and negative electrode;There is hot melt adhesive layer on the growth substrate, and the bottom surface of light emitting chip is partially covered, and the positive electrode, the negative electrode and the region between the two on the bottom surface of light emitting chip are exposed to hot melt adhesive layer;When the light emitting chip on the growth substrate is transferred to the circuit board, the side of growth substrate grown with light emitting chip is set with the side of circuit board with chip bonding area after alignment, then heat hot melt adhesive layer at least to make the region covered on the bottom surface of light emitting chip liquefied and flow to the glue column formed on the two sides of circuit board in light emitting chip, the channel formed by the glue column on the two sides of light emitting chip after being peeled off from growth substrate falls on the corresponding chip bonding area, so as to realize the direct transfer of light emitting chip to the circuit board, transfer efficiency is higher, and transfer cost is lower.

Description

Technical Field

[0001] This invention relates to the field of light-emitting chips, and more particularly to a growth substrate assembly, a light-emitting component, and a method for manufacturing the same. Background Technology

[0002] Micro-LED is a next-generation display technology. Compared with existing liquid crystal displays, it has higher photoelectric efficiency, higher brightness, higher contrast, and lower power consumption, and can also be combined with flexible panels to achieve flexible displays.

[0003] A Micro-LED display panel comprises several pixel regions (SPRs, or Subpixel Rendering areas), each SPR containing a red Micro-LED chip, a blue Micro-LED chip, and a green Micro-LED chip. During the display panel manufacturing process, the red, blue, and green Micro-LED chips need to be transferred from their respective growth substrates (WAFERs) to the display backplane. Taking the transfer process of the red Micro-LED chip as an example, the process is as follows:

[0004] The side of the temporary substrate with the first adhesive layer is attached to the side of the growth substrate on which the red Micro-LED chip is grown. Then the growth substrate is peeled off and the red Micro-LED chip is transferred to the temporary substrate.

[0005] The side of the transfer substrate with the second adhesive layer is attached to the side of the temporary substrate that carries the red Micro-LED chip, thereby selectively picking up the corresponding red Micro-LED chip from the temporary substrate.

[0006] The red Micro-LED chip picked up by the transfer substrate is transferred to the corresponding chip bonding area on the display backplane.

[0007] In the chip transfer process described above, two adhesive materials need to be selected to make the first adhesive layer and the second adhesive layer respectively. It is also necessary to ensure that the adhesion of the first adhesive layer is lower than that of the second adhesive layer. It is difficult to find suitable materials. In addition, the transfer process requires transferring the Micro-LED chip from the growth substrate to the temporary substrate and from the temporary substrate to the transfer substrate. The transfer efficiency is low and it is necessary to prepare the temporary substrate and the transfer substrate. The transfer cost is also high.

[0008] Therefore, improving the transfer efficiency of LED chips and reducing transfer costs are urgent problems that need to be solved. Summary of the Invention

[0009] In view of the shortcomings of the prior art, the purpose of this invention is to provide a growth substrate assembly, a light-emitting assembly and a method for manufacturing the same, in order to solve the problem of how to improve the transfer efficiency of LED chips and reduce the transfer cost in related technologies.

[0010] This invention provides a growth substrate assembly, comprising:

[0011] Growth substrate;

[0012] A plurality of light-emitting chips are disposed on the growth substrate, and positive and negative electrodes are grown on the bottom surface of the plurality of light-emitting chips, wherein the bottom surface is the side of the light-emitting chip away from the growth substrate;

[0013] A hot melt adhesive layer is disposed on the growth substrate to cover the bottom surface of the light-emitting chip, and the positive electrode, the negative electrode, and the area between the positive electrode and the negative electrode on the bottom surface of the light-emitting chip are exposed in the hot melt adhesive layer.

[0014] The aforementioned growth substrate assembly has a plurality of light-emitting chips on its growth substrate. The bottom surface of each light-emitting chip is away from the growth substrate and has a positive electrode and a negative electrode grown thereon. A hot melt adhesive layer is provided on the growth substrate to cover the bottom surface of the light-emitting chips, and the positive electrode and negative electrode of the light-emitting chips and the area between them are exposed in the hot melt adhesive layer. When transferring the light-emitting chips on the growth substrate to the circuit board, the side of the growth substrate with the light-emitting chips is aligned with the side of the circuit board with the chip bonding area. The hot melt adhesive layer is heated to at least liquefy (i.e. melt) the area covering the bottom surface of the light-emitting chips and then flows onto the circuit board under gravity, forming adhesive pillars on both sides of each light-emitting chip. This allows the light-emitting chips to be peeled off from the growth substrate and fall onto their respective chip bonding areas along the channels formed by the adhesive pillars on both sides. This achieves direct transfer of the light-emitting chips to the circuit board. The entire process eliminates the need to transfer the light-emitting chips from the growth substrate to a temporary substrate and then from the temporary substrate to a transfer substrate, and also eliminates the need to prepare temporary substrates and transfer substrates. This results in higher transfer efficiency and lower transfer cost.

[0015] Based on the same inventive concept, the present invention also provides a method for manufacturing the growth substrate assembly as described above, comprising:

[0016] A plurality of the light-emitting chips are grown on a growth substrate;

[0017] A sacrificial layer unit is disposed on the bottom surface of each of the light-emitting chips, and each sacrificial layer unit covers the positive electrode, the negative electrode and the area between the positive electrode and the negative electrode on the bottom surface of each of the light-emitting chips.

[0018] A hot melt adhesive layer is formed on the growth substrate, the hot melt adhesive layer covers the bottom surface of the plurality of light-emitting chips, and the sacrificial layer unit is exposed to the hot melt adhesive layer;

[0019] After the hot melt adhesive layer has cured, each of the sacrificial layer units is removed, so that the positive electrode, the negative electrode, and the area between the positive electrode and the negative electrode of each light-emitting chip are exposed to the hot melt adhesive layer.

[0020] The growth substrate assembly produced by the above-described method of manufacturing the growth substrate assembly no longer requires transferring the light-emitting chip from the growth substrate to a temporary substrate and then from the temporary substrate to a transfer substrate during the process of transferring the light-emitting chip on the growth substrate assembly to the circuit board. It also eliminates the need to prepare temporary substrates and transfer substrates, resulting in higher chip transfer efficiency and lower transfer costs.

[0021] Based on the same inventive concept, the present invention also provides a method for manufacturing a light-emitting component, comprising:

[0022] The growth substrate assembly is manufactured using the method described above.

[0023] The side of the growth substrate on which the light-emitting chip is grown is placed on the circuit board and aligned with the side of the circuit board on which the chip bonding area is provided.

[0024] The hot melt adhesive layer is first heated, causing it to liquefy and flow onto the circuit board, forming adhesive pillars on both sides of the light-emitting chip;

[0025] The light-emitting chip on the growth substrate is peeled off from the growth substrate, and the peeled light-emitting chip falls into its corresponding chip bonding area along the channel formed by the adhesive pillars on both sides.

[0026] The hot melt adhesive layer is removed along with the growth substrate, and the pads in each chip bonding area are connected to the positive and negative electrodes of the corresponding light-emitting chip.

[0027] The above method for manufacturing light-emitting components eliminates the need to transfer the light-emitting chip from the growth substrate to the temporary substrate and then from the temporary substrate to the transfer substrate during the process of transferring the light-emitting chip from the growth substrate to the circuit board. It also eliminates the need to prepare temporary substrates and transfer substrates. The chip transfer efficiency is higher and the transfer cost is lower, resulting in higher manufacturing efficiency and lower manufacturing cost for the light-emitting component.

[0028] Based on the same inventive concept, the present invention also provides a light-emitting component, which is manufactured by the light-emitting component manufacturing method described above.

[0029] The light-emitting chip of the above-mentioned light-emitting component is directly transferred from the growth substrate component to the circuit board. The entire transfer process does not require transferring the light-emitting chip from the growth substrate to the temporary substrate and then from the temporary substrate to the transfer substrate. There is also no need to prepare temporary substrates and transfer substrates. The chip transfer efficiency is higher and the transfer cost is lower, which makes the manufacturing efficiency of the light-emitting component higher and the manufacturing cost lower. Attached Figure Description

[0030] Figure 1-1 This is a schematic diagram showing the transfer of three colors of Micro-LED chips from the growth substrate to the display backplane in the related technology.

[0031] Figure 1-2 This is a schematic diagram illustrating the process of transferring red light Micro-LED chips in related technologies;

[0032] Figure 1-3 This is a schematic diagram of the bonding area between the temporary substrate and the growth substrate in the related technology;

[0033] Figure 1-4 This is a schematic diagram of a temporary substrate carrying a red Micro-LED chip in a related technology.

[0034] Figure 1-5 This is a schematic diagram of a temporary substrate after some of the red Micro-LED chips have been removed in a related technology.

[0035] Figure 1-6 A schematic diagram of the display backplane after Micro-LED chip transfer and bonding;

[0036] Figure 2 This is a schematic diagram of the growth substrate structure provided in an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of the growth substrate assembly structure provided in an embodiment of the present invention;

[0038] Figure 4 Schematic diagram of the growth substrate assembly structure provided in the embodiments of the present invention Figure 2 ;

[0039] Figure 5 Schematic diagram of the growth substrate assembly structure provided in the embodiments of the present invention Figure 3 ;

[0040] Figure 6 This is a schematic diagram of a method for fabricating a growth substrate assembly according to another optional embodiment of the present invention;

[0041] Figure 7 This is a schematic diagram of the fabrication process of a growth substrate assembly provided in another optional embodiment of the present invention;

[0042] Figure 8 This is a schematic diagram illustrating the manufacturing process of a light-emitting component, provided as another optional embodiment of the present invention.

[0043] Figure 9 This is a schematic diagram of the manufacturing process of a light-emitting component provided in another optional embodiment of the present invention;

[0044] Figure 10 This is a schematic diagram of the bonding between the growth substrate and the circuit board provided in another optional embodiment of the present invention;

[0045] Figure 11 A schematic diagram of the first light-emitting chip transfer process provided in another optional embodiment of the present invention;

[0046] Figure 12 This is a schematic diagram of the second light-emitting chip transfer process provided in another optional embodiment of the present invention;

[0047] Figure 13 A schematic diagram of the third light-emitting chip transfer process provided in another optional embodiment of the present invention;

[0048] Explanation of reference numerals in the attached figures:

[0049] 10-Growth substrate, 101-Red Micro-LED chip, 102-Chip vacancy, 20-Temporary substrate, 201-First adhesive layer, 30-Transfer substrate, 301-Second adhesive layer, 302-Display backplate, 4-Growth substrate, 41-First growth substrate, 42-Second growth substrate, 43-Third growth substrate, 5-Light-emitting chip, 50-Electrode, 51-First light-emitting chip, 52-Second light-emitting chip, 53-Third light-emitting chip, 6-Hot melt adhesive layer, 61-Hot melt adhesive unit, 62-Adhesive pillar, 7-Sacrificial layer unit, 8-Circuit board, 81-Pad. Detailed Implementation

[0050] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0052] In Micro-LED display technology, see Figure 1-1As shown, the red, blue, and green Micro-LED chips need to be transferred from their respective growth substrates to the display backplane. For example, the transfer process for the red Micro-LED chip is described in [link to documentation]. Figures 1-2 to 1-5 As shown, it includes:

[0053] S201: The side of the temporary substrate 20 with the first adhesive layer 201 is bonded to the side of the growth substrate 10 on which the red Micro-LED chip 101 is grown; see one top view after bonding. Figure 1-3 As shown;

[0054] S202 to S203: The growth substrate 10 is peeled off, and the red Micro-LED chip 101 is transferred onto the temporary substrate 20; a top view of the temporary substrate 20 at this time is shown below. Figure 1-4 As shown;

[0055] S204: The side of the transfer substrate 30 with the second adhesive layer 301 is bonded to the side of the temporary substrate 20 carrying the red Micro-LED chip 101, thereby selectively picking up the corresponding red Micro-LED chip 101 from the temporary substrate 101; see also Figure 1-5 As shown, after the red Micro-LED chip at the corresponding position on the temporary substrate 20 is picked up, a corresponding chip empty space 102 is left.

[0056] S205: Transfer the red Micro-LED chip picked up by the transfer substrate 20 to the corresponding chip bonding area on the display backplate 302.

[0057] The blue and green Micro-LED chips were also transferred to the display backplane using the same chip transfer process described above. The display backplane that completes the transfer of all Micro-LED chips is shown below. Figure 1-6 As shown.

[0058] In the chip transfer process described above, two adhesive materials need to be selected to make the first adhesive layer 201 and the second adhesive layer 301 respectively. It is also necessary to ensure that the adhesion of the first adhesive layer 201 is lower than that of the second adhesive layer 301. It is difficult to find suitable materials. In addition, the transfer process requires transferring the Micro-LED chip from the growth substrate 10 to the temporary substrate 20 and from the temporary substrate 20 to the transfer substrate 30. The transfer efficiency is low and it is necessary to prepare the temporary substrate 10 and the transfer substrate 20. The transfer cost is also high.

[0059] Based on this, the present invention aims to provide a solution that can solve the above-mentioned technical problems, the details of which will be described in subsequent embodiments.

[0060] This embodiment provides a growth substrate assembly, including:

[0061] In this embodiment, the shape and material of the growth substrate are not limited. For example, it can be a rectangular substrate or a circular substrate, and its material can be, but is not limited to, a silicon substrate.

[0062] A plurality of light-emitting chips are disposed on a growth substrate, and electrodes are grown on the bottom surface of the light-emitting chips, including positive electrodes and negative electrodes; wherein the bottom surface of the light-emitting chip is the side of the light-emitting chip away from the growth substrate. It should be understood that the light-emitting chip in this embodiment can be replaced with other electronic chips, such as resistor chips, capacitor chips, driver chips, control chips, etc., according to application requirements, which will not be described in detail here.

[0063] It should be understood that the light-emitting chip in this embodiment can be a micro light-emitting chip, such as at least one of Mini LED chips and Micro-LED chips, or a common light-emitting chip with a size greater than or equal to 200 micrometers.

[0064] The growth substrate assembly in this embodiment further includes a hot melt adhesive layer disposed on the growth substrate, covering the bottom surface of the light-emitting chip. The positive electrode, negative electrode, and the area between the positive and negative electrodes on the bottom surface of the light-emitting chip are exposed by the hot melt adhesive layer. That is, in this embodiment, the hot melt adhesive layer only covers a portion of the bottom surface of the light-emitting chip, leaving the positive electrode, negative electrode, and the area between the positive and negative electrodes exposed. In this embodiment, the positive electrode, negative electrode, and the area between the positive and negative electrodes of the light-emitting chip can be completely exposed by the hot melt adhesive layer, or only partially exposed, but it is necessary to ensure that the bottom surface of the electrode (i.e., the side of the electrode away from the growth substrate) is exposed outside the hot melt adhesive layer. In this embodiment, the hot melt adhesive layer can change from a solidified state to a liquefied (i.e., melted) state when heated to a certain degree, and flow downwards along both sides of the light-emitting chip under the action of gravity, thereby forming adhesive pillars on both sides of the light-emitting chip.

[0065] Furthermore, in one example of this embodiment, the hot melt adhesive layer can be, but is not limited to, a non-conductive adhesive layer. Of course, in other application examples, the hot melt adhesive layer can also be a conductive adhesive layer.

[0066] In this embodiment, when transferring the light-emitting chip on the growth substrate to the circuit board, the side of the growth substrate with the light-emitting chip is aligned with the side of the circuit board with the chip bonding area. The hot melt adhesive layer is heated to at least liquefy the area covering the bottom surface of the light-emitting chip. The liquefied hot melt adhesive layer flows onto the circuit board under gravity and forms adhesive pillars on both sides of the light-emitting chip. After the light-emitting chip on the growth substrate is peeled off, it falls onto its corresponding chip bonding area along the channels formed by the adhesive pillars on both sides. This achieves direct transfer of the light-emitting chip to the circuit board. The entire process does not require transferring the light-emitting chip from the growth substrate to a temporary substrate and then from the temporary substrate to the transfer substrate. It also eliminates the need to prepare temporary substrates and transfer substrates, resulting in higher transfer efficiency and lower transfer cost. Furthermore, when the light-emitting chip falls from the growth substrate to the corresponding chip bonding area on the circuit board, it falls along the channel formed by the adhesive pillars on both sides. This ensures that the light-emitting chip falls accurately to its corresponding chip bonding area. Moreover, due to the limiting effect of the adhesive pillars on both sides, the light-emitting chip can be prevented from flipping or tilting during the falling process, which can further improve the quality and reliability of chip transfer bonding.

[0067] In this embodiment, the circuit board can be a display back panel, or various circuit boards for lighting, and can be a flexible circuit board or a rigid circuit board. When it is a display back panel, the display back panel can be, but is not limited to, a glass back panel or a PCB board.

[0068] In this embodiment, the circuit board has multiple chip bonding areas, each containing pads corresponding to the positive and negative electrodes of the light-emitting chip. It should be understood that the number of chip bonding areas and their distribution on the circuit board can be flexibly set according to application requirements. For example, the chip bonding areas can be arranged in an array on the circuit board, or flexibly distributed according to other rules, or even flexibly distributed according to requirements. In some application examples, to facilitate the direct transfer of the light-emitting chip from the growth substrate to the circuit board, the distribution of the chip bonding areas on the circuit board can correspond to the layout and position of the corresponding light-emitting chip on the growth substrate.

[0069] In this embodiment, the hot melt adhesive layer can be a single integral adhesive layer or it can include several hot melt adhesive units. Each hot melt adhesive unit corresponds to a light-emitting chip. Each hot melt adhesive unit is separate from the others. The hot melt adhesive unit covers the bottom part of the light-emitting chip it corresponds to, and the electrodes of the light-emitting chip are exposed on the hot melt adhesive layer.

[0070] In addition, it should be understood that in this embodiment, one light-emitting chip can be set in a chip bonding area, or multiple light-emitting chips can be set as needed. When multiple light-emitting chips are set, these multiple light-emitting chips are transferred in one chip transfer process.

[0071] To facilitate understanding, the following explanation uses several examples of growth substrate assembly structures.

[0072] See an example of a growth substrate assembly. Figures 2 to 3 As shown, the assembly includes a growth substrate 4, a plurality of light-emitting chips 5 formed on the growth substrate 4, and an electrode 50 on the bottom surface of each light-emitting chip 5, i.e., the electrode 50 is located on the side of the light-emitting chip 5 away from the growth substrate 4. The electrode 50 includes a positive electrode and a negative electrode. The growth substrate assembly also includes a hot melt adhesive layer 6 disposed on the growth substrate 4, covering at least a portion of the bottom surface of each light-emitting chip 5. In this example, the hot melt adhesive layer 6 is flush with the electrodes 50 (i.e., the positive and negative electrodes) of the light-emitting chip 5. The positive electrode, the negative electrode, and the area between them are exposed in the hot melt adhesive layer 6. The hot melt adhesive layer 6 may also be slightly higher or slightly lower than the electrodes 50. In this example, the hot melt adhesive layer 6 is an integrally formed adhesive layer, i.e., the gaps between each light-emitting chip 5 are also filled and covered by the hot melt adhesive layer 6.

[0073] See another example of a growth substrate assembly. Figure 4 As shown, it includes a growth substrate 4, a plurality of light-emitting chips 5 formed on the growth substrate 4, and electrodes 50 (including positive and negative electrodes) on the bottom surface of each light-emitting chip 5. The growth substrate assembly also includes a hot melt adhesive layer 6 disposed on the growth substrate 4, covering at least a portion of the bottom surface of each light-emitting chip 5. In this example, the hot melt adhesive layer 6 is flush with the electrodes 50 of the light-emitting chip 5, or slightly higher or slightly lower than the electrodes 50. In this example, the hot melt adhesive layer 6 includes a plurality of hot melt adhesive units 61, one hot melt adhesive unit 61 corresponding to one light-emitting chip 5, and each hot melt adhesive unit 61 is separated from each other. The hot melt adhesive unit 61 covers the bottom surface of the corresponding light-emitting chip 5, and the bottom surface of the light-emitting chip 5, including the positive electrode, the negative electrode, and the area between them, is exposed to the hot melt adhesive unit 61. The shape of the hot melt adhesive unit 61 in this embodiment can be flexibly set, for example, it can be... Figure 4 The arc shown can also be Figure 5 The rectangles shown can be other regular or irregular shapes; no restrictions are placed on them here.

[0074] It should be understood that in this embodiment, the hot melt adhesive layer can also cover at least a portion of the area between the positive and negative electrodes of the light-emitting chip, as long as the hot melt adhesive covering the area can flow along both sides of the light-emitting chip to the circuit board to form adhesive pillars after being heated and turning into a liquid state.

[0075] In this embodiment, the growth substrate 4 may include, but is not limited to, a growth substrate for growing red light-emitting chips, a growth substrate for growing green light-emitting chips, a growth substrate for growing blue light-emitting chips, a growth substrate for growing ultraviolet light-emitting chips, etc., and can be flexibly set according to application requirements. In this embodiment, when transferring the light-emitting chip 5 on the growth substrate 4 to the circuit board, after aligning the side of the growth substrate 4 with the side of the circuit board with the chip bonding area, the hot melt adhesive layer 6 is heated to at least liquefy the area covering the bottom surface of the light-emitting chip 5. The liquefied hot melt adhesive layer 6 flows onto the circuit board under the action of gravity and forms adhesive pillars on both sides of the light-emitting chip. At this time, the light-emitting chip 5 on the growth substrate 4 is peeled off from the growth substrate 4 and falls onto its corresponding chip bonding area along the channels formed by the adhesive pillars on both sides, thereby realizing the direct and accurate transfer of the light-emitting chip 5 to the circuit board. The whole process is fast and simple, without the need to transfer the light-emitting chip from the growth substrate to a temporary substrate and then from the temporary substrate to the transfer substrate, and there is no need to prepare a temporary substrate or a transfer substrate. The transfer efficiency is higher and the transfer cost is lower.

[0076] Another alternative embodiment:

[0077] For ease of understanding, this embodiment will be described below using an example fabrication method of the above-described growth substrate assembly. See [link to documentation]. Figure 6 As shown, it includes, but is not limited to:

[0078] S601: Several light-emitting chips are grown on a growth substrate. Electrodes (including positive and negative electrodes) are grown on the bottom surface of the light-emitting chips. The bottom surface of the light-emitting chips is the side of the light-emitting chips that is away from the growth substrate.

[0079] It should be understood that the method of growing light-emitting chips on the growth substrate in this embodiment can adopt various methods of growing light-emitting chips, and there is no limitation on them here.

[0080] S602: Sacrificial layer units are provided on the bottom surface of each light-emitting chip, and each sacrificial layer unit covers the positive electrode, negative electrode and the area between the positive electrode and negative electrode on the bottom surface of each light-emitting chip.

[0081] In this embodiment, the size and shape of each sacrificial layer unit are not limited, as long as it completely covers the positive electrode, negative electrode and the area between them of the light-emitting chip without completely covering the bottom surface of the light-emitting chip.

[0082] In this embodiment, the formation method and specific material of the sacrificial layer unit can be flexibly selected. For example, in some examples, the sacrificial layer unit can be, but is not limited to, a photoresist layer unit or a polyvinyl alcohol layer unit. As long as it can be removed after a weakening layer is subsequently formed on it.

[0083] S603: A hot melt adhesive layer is formed on the growth substrate, which covers the bottom surface of several light-emitting chips. The sacrificial layer units are exposed to the hot melt adhesive layer to facilitate the subsequent removal of the sacrificial layer units.

[0084] S604: After the hot melt adhesive layer has cured, remove each sacrificial layer unit so that the positive electrode, negative electrode and the area between the positive electrode and negative electrode on the bottom surface of each light-emitting chip are exposed to the hot melt adhesive layer.

[0085] For example, when the sacrificial layer unit is a photoresist unit, the photoresist unit can be cleaned away, thereby exposing the electrodes of the light-emitting chip covered by it to the hot melt adhesive layer.

[0086] In the field of Micro-LED displays, the number of Micro-LED chips transferred to the display backplane is typically in the tens of thousands or higher. Therefore, after the Micro-LED chips are transferred, it is difficult to detect defects on the display backplane, and even if defects are detected, they are difficult to repair, and the repair process is complex. Furthermore, existing methods of Micro-LED chip transfer involve laser peeling of the entire surface of the Micro-LED chips on the growth substrate, transferring all Micro-LED chips to a temporary substrate. This results in uncontrollable chip quality in the final Micro-LED display device, leading to high repair costs. Additionally, because the emission wavelength of the Micro-LED chips cannot be pre-selected, the resulting display device exhibits poor light emission uniformity. To address this issue, in this embodiment, before setting the sacrificial layer unit on the bottom surface of each light-emitting chip in step S602, the following may also be included, but not limited to:

[0087] Each light-emitting chip on the growth substrate is inspected, and any unqualified chips are removed from the growth substrate. This ensures that only qualified chips remain on the growth substrate, minimizing the possibility of defects in the chips transferred to the circuit board. Consequently, subsequent defect detection and repair are reduced, improving product quality and lowering maintenance costs.

[0088] In this embodiment, the detection of each light-emitting chip on the growth substrate may include, but is not limited to, at least one of the following:

[0089] Inspect the appearance of each light-emitting chip;

[0090] The optical characteristics of each light-emitting chip are tested.

[0091] For example, in one instance, mapping data can be generated in advance based on the optical characteristics and appearance quality of the light-emitting chips on the growth substrate, without being limited to Micro PL / AOI detection, thereby identifying unqualified light-emitting chips and removing them from the growth substrate.

[0092] In some examples of this embodiment, the detection of the optical characteristics of each light-emitting chip may include, but is not limited to: detecting the main wavelength of each light-emitting chip, and determining that the light-emitting chip whose main wavelength differs from the preset standard main wavelength by more than the preset difference is an unqualified light-emitting chip, thereby making the main wavelength of the light-emitting chips retained on the growth substrate more consistent, thereby improving the light emission uniformity of the light-emitting component and making its display effect or lighting effect better.

[0093] For ease of understanding, the following section uses the sacrificial layer unit as the photoresist layer unit to illustrate the fabrication process. Figure 4 The process of growing the substrate assembly shown is illustrated as an example; for Figure 3 , Figure 5 The fabrication process of the growth substrate components shown is similar and will not be described in detail here.

[0094] Production Figure 4 See one example of the growth substrate assembly shown. Figure 7 As shown, it includes, but is not limited to:

[0095] S701: A plurality of light-emitting chips 5 are grown on the growth substrate 4. Electrodes 50 (including positive electrodes and negative electrodes) are grown on the bottom surface of the plurality of light-emitting chips 5. The bottom surface of the light-emitting chip 5 is the side of the light-emitting chip 5 away from the growth substrate.

[0096] It should be understood that the method of growing the light-emitting chip 5 on the growth substrate in this example can be any of the various growth methods of the light-emitting chip 5, which will not be elaborated here.

[0097] S702: Sacrificial layer units 7 are provided on the bottom surface of each light-emitting chip 5, and each sacrificial layer unit 7 covers the positive electrode, negative electrode and the area between the positive electrode and negative electrode on the bottom surface of each light-emitting chip.

[0098] In this example, each sacrificial layer unit 7 is arc-shaped, and all sacrificial layer units 7 have the same shape. Of course, some may be the same and some may be different. Moreover, its shape is not limited to arc shape; it can also be rectangular, etc., which will not be elaborated here.

[0099] S703: A plurality of hot melt adhesive units 61 are formed on the growth substrate 4. The plurality of hot melt adhesive units 61 cover a portion of the bottom surface of a plurality of light-emitting chips 5 respectively. The sacrificial layer unit 7 is exposed to the hot melt adhesive units 61 so as to facilitate the subsequent removal of the sacrificial layer unit 7.

[0100] S704: After the hot melt adhesive layer has cured, each sacrificial layer unit 7 is removed, exposing the positive electrode, negative electrode, and the area between the positive and negative electrodes on the bottom surface of each light-emitting chip 5 to the hot melt adhesive unit 61, thereby obtaining... Figure 4 The growth substrate assembly shown.

[0101] As can be seen, the method for fabricating the growth substrate assembly provided in this embodiment is simple, convenient, and highly efficient. When transferring the light-emitting chip on the growth substrate assembly to the circuit board, it is no longer necessary to transfer the light-emitting chip from the growth substrate to the temporary substrate and then from the temporary substrate to the transfer substrate. It is also no longer necessary to prepare temporary substrates and transfer substrates. The chip transfer efficiency is higher and the transfer cost is lower.

[0102] Another alternative embodiment:

[0103] This embodiment also provides a light-emitting component, which is fabricated using the growth substrate assembly described in the above embodiments. For ease of understanding, this embodiment will be explained below using the fabrication method of the light-emitting component as an example. Please refer to... Figure 8 As shown, the methods for manufacturing light-emitting components may include, but are not limited to:

[0104] S801: Fabrication of growth substrate assembly; In this embodiment, it can be fabricated by, but is not limited to, the growth substrate assembly fabrication method shown in the above embodiments, and will not be described again here.

[0105] S802: The side of the growth substrate on which the light-emitting chip is grown is placed on the circuit board and aligned with the side of the circuit board on which the chip bonding area is located.

[0106] In this embodiment, when the side of the growth substrate on which the light-emitting chip is grown is placed on the circuit board and aligned with the side of the circuit board on which the chip bonding area is located, the positive and negative electrodes of the light-emitting chip can directly contact the corresponding pads in the chip bonding area on the circuit board, and there is a certain gap between the hot melt adhesive layer and the circuit board.

[0107] Of course, in this embodiment, when the side of the growth substrate on which the light-emitting chip is grown is placed on the circuit board and aligned with the side of the circuit board on which the chip bonding area is located, a certain gap can be maintained between the electrode of the light-emitting chip and the corresponding pad in the chip bonding area on the circuit board, and a certain gap can also be maintained between the hot melt adhesive layer and the circuit board.

[0108] S803: Perform the first heating on the hot melt adhesive layer so that the hot melt adhesive layer liquefies and flows onto the circuit board, forming glue columns on both sides of the light-emitting chip.

[0109] Of course, after the first heating of the hot melt adhesive layer, other areas of the hot melt adhesive layer can also be liquefied. In this embodiment, the specific temperature and heating time used for the first heating can be flexibly set according to the specific material of the hot melt adhesive layer and the required liquefaction state of the hot melt adhesive layer, and no limitation is imposed on this here.

[0110] S804: Peel the light-emitting chip on the growth substrate from the growth substrate, and the peeled light-emitting chip falls onto their respective corresponding chip bonding areas along the channels formed by the glue columns on both sides.

[0111] In this embodiment, the method of peeling the light-emitting chip on the growth substrate from the growth substrate can be flexibly adopted. For example, but not limited to, laser peeling can be used.

[0112] In this embodiment, when the light-emitting chip falls from the growth substrate onto the corresponding chip bonding area on the circuit board, it falls along the channels formed by the glue columns on both sides, so as to ensure that the light-emitting chip accurately falls onto its corresponding chip bonding area. And due to the limitation of the glue columns on both sides, it can also prevent the light-emitting chip from flipping or tilting during the falling process, etc., which can further improve the quality and reliability of chip transfer bonding.

[0113] S805: Remove the hot melt adhesive layer together with the growth substrate, and connect the pads in each chip bonding area to the positive electrode and negative electrode of the corresponding light-emitting chip. In this step, since the growth substrate is a substrate made of sapphire or the like, the circuit board is densely covered with metal lines and an inorganic protective layer; the characteristic of the hot melt adhesive layer is poor wettability with metals, so it is easier to separate from the circuit board; in addition, even if there is residue of the hot melt adhesive layer on the circuit board, when heating and welding the electrodes of the light-emitting chip and the pads in the chip bonding area later, the hot melt adhesive layer will gather in places without metal solder and will not interfere with the electrical connection of the light-emitting chip.

[0114] In some examples of this embodiment, in order to facilitate the removal of the hot melt adhesive layer, removing the hot melt adhesive layer together with the growth substrate in the above S805 includes:

[0115] Perform the second heating on the hot melt adhesive layer to further liquefy it, and then remove the hot melt adhesive layer together with the growth substrate.

[0116] As can be seen, in the fabrication of light-emitting components, the side of the growth substrate with the light-emitting chip grown can be directly aligned with the circuit board. Then, the hot melt adhesive layer is heated to at least the area covering the bottom surface of the light-emitting chip, which is then liquefied. Under the action of gravity, the liquefied hot melt adhesive layer flows along both sides of the light-emitting chip to the circuit board, forming adhesive pillars. At this point, the light-emitting chip on the growth substrate is peeled off from the growth substrate and falls along the channels formed by the adhesive pillars on both sides to its corresponding chip bonding area. This achieves the direct transfer of the light-emitting chip to the circuit board. The entire chip transfer process no longer requires a temporary substrate, transfer substrate, or transfer head, resulting in higher manufacturing efficiency and lower manufacturing cost.

[0117] To facilitate understanding, this embodiment will be described below using an application scenario as an example. In this application scenario, the light-emitting chips on the circuit board are all of the same color. The fabrication process of the light-emitting component in this application scenario is described in [link to documentation]. Figure 9 As shown, it includes, but is not limited to:

[0118] S901: The side of the growth substrate 4 on which the light-emitting chip 5 is grown is placed on the circuit board 8 and aligned with the side of the circuit board 8 on which the chip bonding area is provided. The chip bonding area is provided with pads 81 that correspond to the positive electrode and the negative electrode of the light-emitting chip 5, respectively.

[0119] In this embodiment, when the side of the growth substrate 4 on which the light-emitting chip 5 is grown is disposed on the circuit board 8 and aligned with the side of the circuit board 8 having the chip bonding area, at least one of the positive electrode and negative electrode of the light-emitting chip 5 can directly contact the corresponding pad 81 in the chip bonding area on the circuit board 8. For example, see [reference needed]. Figure 10 As shown, there is a certain gap between the hot melt adhesive unit 61 and the circuit board 4.

[0120] Of course, in this embodiment, when the side of the growth substrate 4 on which the light-emitting chip 5 is grown is disposed on the circuit board 8 and aligned with the side of the circuit board 8 having the chip bonding area, a certain gap can also be maintained between the positive and negative electrodes of the light-emitting chip 5 and the corresponding pads 81 in the chip bonding area on the circuit board 8, and there is also a certain gap between the hot melt adhesive unit 61 and the circuit board 8. See [link to relevant documentation]. Figure 9 As shown.

[0121] S902: The hot melt adhesive unit 61 is heated for the first time, so that at least the area covered by it on the bottom surface is liquefied and flows along both sides of the light-emitting chip 5 to the circuit board under the action of gravity to form adhesive pillars 62, thereby achieving a relatively fixed effect, and the adhesive pillars 62 form a channel for the light-emitting chip 5 to fall onto the circuit board; the light-emitting chip 5 on the growth substrate 4 is peeled off from the growth substrate 4, and the peeled light-emitting chip 5 falls along the above-mentioned channel onto its corresponding chip bonding area.

[0122] Of course, after the first heating of the hot melt adhesive unit 61, other areas of the hot melt adhesive unit 61 can also be liquefied. In this embodiment, the specific temperature and heating time used for the first heating can be flexibly set according to the specific material of the hot melt adhesive unit 61 and the required liquefaction state of the hot melt adhesive unit 61, and there are no restrictions on them here.

[0123] S903: Remove the hot melt adhesive unit 61 along with the growth substrate 4, and connect the pads 81 in each chip bonding area to the positive and negative electrodes of their respective light-emitting chips 5.

[0124] For example, the hot melt adhesive unit 61 can be heated a second time to further liquefy it, and then the hot melt adhesive unit 61 can be removed together with the growth substrate.

[0125] Even if hot melt adhesive remains on the circuit board during this step, it will accumulate in areas without solder when the electrodes of the light-emitting chip and the pads in the chip bonding area are heated and soldered subsequently, thus not interfering with the electrical connection of the light-emitting chip.

[0126] For ease of understanding, this embodiment will be described below with reference to another application scenario. In this example, the growth substrate includes a first growth substrate, a second growth substrate, and a third growth substrate on which a first light-emitting chip (e.g., a red light-emitting chip), a second light-emitting chip (e.g., a green light-emitting chip), and a third light-emitting chip (e.g., a blue light-emitting chip) are respectively grown.

[0127] The following example illustrates the process of sequentially transferring the first, second, and third light-emitting chips to the circuit board.

[0128] See the process of transferring the first light-emitting chip to the circuit board. Figure 11 As shown, it includes:

[0129] S1101: The side of the first growth substrate 41 on which the first light-emitting chip 51 is grown is disposed on the circuit board 8 and aligned with the side of the circuit board 8 on which the chip bonding area is provided, wherein the chip bonding area is provided with pads 81 corresponding to the positive electrode and negative electrode of the first light-emitting chip 51.

[0130] S1102: The hot melt adhesive unit 61 is first heated so that at least the area covering the bottom surface is liquefied and flows along both sides of the first light-emitting chip 51 to the circuit board under the action of gravity to form adhesive pillars 62, thereby playing a role in relatively fixing and forming a channel for the first light-emitting chip 51 to fall; the first light-emitting chip 51 on the first growth substrate 41 is peeled off from the first growth substrate 4, and the peeled first light-emitting chip 51 falls along the channels formed by the adhesive pillars 62 on both sides to its respective chip bonding area.

[0131] S1103: After the hot melt adhesive unit 61 is heated a second time to further liquefy it, the hot melt adhesive unit 61 is removed together with the first growth substrate 41.

[0132] See the process of transferring the second light-emitting chip to the circuit board. Figure 12 As shown, it includes:

[0133] S1201: The side of the second growth substrate 42 on which the second light-emitting chip 52 is grown is disposed on the circuit board 8 and aligned with the side of the circuit board 8 on which the chip bonding area is provided, wherein the chip bonding area is provided with pads 81 corresponding to the positive electrode and the negative electrode of the second light-emitting chip 52.

[0134] See Figure 12 As shown, the previously transferred first light-emitting chip 51 on the circuit board 8 will not interfere with the subsequently transferred second light-emitting chip 52.

[0135] S1202: The hot melt adhesive unit 61 is first heated so that the area at least covered on the bottom surface is liquefied and flows along both sides of the second light-emitting chip 52 to the circuit board under the action of gravity to form adhesive pillars 62, thereby playing a role in relatively fixing and forming a channel for the second light-emitting chip 52 to fall; and the second light-emitting chip 52 on the second growth substrate 42 is peeled off from the first growth substrate 4, and the peeled second light-emitting chip 52 falls along the channels formed by the adhesive pillars 62 on both sides to their respective chip bonding areas.

[0136] S1203: The hot melt adhesive unit 61 can be heated a second time to further liquefy it, and then the hot melt adhesive unit 61 can be removed together with the second growth substrate 42.

[0137] See the process of transferring the third light-emitting chip to the circuit board. Figure 13 As shown, it includes:

[0138] S1301: The side of the third growth substrate 43 on which the third light-emitting chip 53 is grown is disposed on the circuit board 8 and aligned with the side of the circuit board 8 on which the chip bonding area is provided, wherein the chip bonding area is provided with pads 81 corresponding to the positive electrode and negative electrode of the third light-emitting chip 53.

[0139] See Figure 12 As shown, the previously transferred first light-emitting chip 51 and second light-emitting chip 52 on the circuit board 8 will not interfere with the subsequently transferred third light-emitting chip 53.

[0140] S1302: The hot melt adhesive unit 61 is first heated so that the area at least covered on the bottom surface is liquefied and flows along both sides of the third light-emitting chip 53 to the circuit board under the action of gravity to form adhesive pillars 62, thereby playing a role in relatively fixing and forming a channel for the third light-emitting chip 53 to fall; the third light-emitting chip 53 on the third growth substrate 43 is peeled off from the first growth substrate 4, and the peeled third light-emitting chip 53 falls along the channels formed by the adhesive pillars 62 on both sides to their respective chip bonding areas.

[0141] S1303: The hot melt adhesive unit 61 can be heated a second time to further liquefy it, and then the hot melt adhesive unit 61 can be removed together with the third growth substrate 43.

[0142] In this example, the positive and negative electrodes of the first light-emitting chip 51, the second light-emitting chip 52, and the third light-emitting chip 53 can be soldered to the pads 81 in the chip bonding area in one go, thereby improving soldering efficiency and consistency. Alternatively, the soldering of the positive and negative electrodes to the pads can be completed after each transfer of a light-emitting chip. It should be understood that the transfer order of the first light-emitting chip 51, the second light-emitting chip 52, and the third light-emitting chip 53 can be flexibly adjusted and is not limited to the order in the above example, which will not be elaborated further here.

[0143] It is evident that in the chip transfer process of the above-mentioned multiple light-emitting colors, it is not necessary to transfer the light-emitting chip from the growth substrate to the temporary substrate and then from the temporary substrate to the transfer substrate. There is also no need to prepare temporary substrates and transfer substrates. The chip transfer efficiency is higher and the transfer cost is lower, which makes the manufacturing efficiency of the light-emitting component higher and the manufacturing cost lower.

[0144] This embodiment also provides a display screen, which can be a flexible display screen or a rigid display screen, and can be a regular-shaped display screen, such as rectangular, circular, or elliptical, or an irregularly shaped display screen. The display screen includes a display screen frame and a display panel as shown in the examples above. The display panel is made of the aforementioned light-emitting components and is fixed within the display screen frame. It should be understood that the display screen in this embodiment can be applied to various electronic devices, such as monitors, computers, mobile phones, smartwatches, in-vehicle devices, billboards, etc. This display screen has higher manufacturing efficiency, lower cost, better yield, higher light emission efficiency, and better display effect.

[0145] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A growth substrate assembly, characterized in that, include: Growth substrate; A plurality of light-emitting chips are disposed on the growth substrate, and positive and negative electrodes are grown on the bottom surface of the plurality of light-emitting chips, wherein the bottom surface is the side of the light-emitting chips away from the growth substrate; A hot melt adhesive layer is disposed on the growth substrate to cover the bottom surface of the light-emitting chip. The bottom surfaces of the positive electrode, the negative electrode, and the area between the positive electrode and the negative electrode on the bottom surface of the light-emitting chip are exposed in the hot melt adhesive layer. The hot melt adhesive layer is flush with the positive electrode and the negative electrode of the light-emitting chip.

2. The growth substrate assembly as described in claim 1, characterized in that, The hot melt adhesive layer includes a plurality of hot melt adhesive units, each hot melt adhesive unit corresponding to one light-emitting chip, and each hot melt adhesive unit is separate from each other, and the hot melt adhesive unit covers the bottom part of the light-emitting chip it corresponds to.

3. The growth substrate assembly as described in claim 1 or 2, characterized in that, The sides of the positive electrode and the sides of the negative electrode on the bottom surface of the light-emitting chip are exposed to the hot melt adhesive layer.

4. The growth substrate assembly as described in claim 1 or 2, characterized in that, The hot melt adhesive layer is a non-conductive adhesive layer.

5. A method for manufacturing a growth substrate assembly as described in any one of claims 1-4, characterized in that, include: A plurality of the light-emitting chips are grown on a growth substrate; A sacrificial layer unit is provided on the bottom surface of each of the light-emitting chips, and each sacrificial layer unit covers the positive electrode, the negative electrode, and the area between the positive electrode and the negative electrode on the bottom surface of each of the light-emitting chips. A hot melt adhesive layer is formed on the growth substrate, the hot melt adhesive layer covers the bottom surface of the plurality of light-emitting chips, and the sacrificial layer unit is exposed to the hot melt adhesive layer; After the hot melt adhesive layer has cured, each of the sacrificial layer units is removed, so that the positive electrode, the negative electrode, and the area between the positive electrode and the negative electrode on the bottom surface of each light-emitting chip are exposed to the hot melt adhesive layer.

6. The method for fabricating the growth substrate assembly as described in claim 5, characterized in that, The sacrificial layer unit is a photoresist layer unit.

7. The method for fabricating the growth substrate assembly as described in claim 5, characterized in that, Before setting the sacrificial layer unit on the bottom surface of each of the light-emitting chips, the method further includes: Each of the light-emitting chips on the growth substrate is inspected; Remove the light-emitting chip that fails the test from the growth substrate; The detection of each of the light-emitting chips on the growth substrate includes at least one of the following: The appearance of each of the light-emitting chips is inspected; The optical characteristics of each of the light-emitting chips are tested.

8. A method for manufacturing a light-emitting component, characterized in that, include: The growth substrate assembly is manufactured using the method for manufacturing the growth substrate assembly as described in any one of claims 5-7; The side of the growth substrate on which the light-emitting chip is grown is placed on the circuit board and aligned with the side of the circuit board on which the chip bonding area is provided. The hot melt adhesive layer is first heated, causing it to liquefy and flow onto the circuit board, forming adhesive pillars on both sides of the light-emitting chip; The light-emitting chip on the growth substrate is peeled off from the growth substrate, and the peeled light-emitting chip falls onto the corresponding chip bonding area along the channel formed by the adhesive pillars on both sides. The hot melt adhesive layer is removed along with the growth substrate, and the pads in each chip bonding area are connected to the positive and negative electrodes of the corresponding light-emitting chip.

9. The method for manufacturing a light-emitting component as described in claim 8, characterized in that, The step of removing the hot melt adhesive layer together with the growth substrate includes: After the hot melt adhesive layer is heated a second time to further liquefy it, the hot melt adhesive layer is removed together with the growth substrate.

10. A light-emitting component, characterized in that, The light-emitting component is manufactured by the method for manufacturing a light-emitting component as described in claim 8 or 9.

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