Light-emitting device with improved adhesive separation and preparation method thereof

Abstract

The present disclosure provides a light-emitting device with improved adhesive detachment and a preparation method thereof, belonging to the field of optoelectronic manufacturing technology. The light-emitting device includes: a carrier board, a plurality of pixel chips and a bearing adhesive layer, wherein the plurality of pixel chips are arranged at intervals on the board surface of the carrier board; the bearing adhesive layer is located on the board surface of the carrier board and in the gaps between the plurality of pixel chips, and the bearing adhesive layer is connected to the side wall of the pixel chip, and at least part of the film layer of the bearing adhesive layer is a hollow structure. The present disclosure can improve the problem of the bearing adhesive layer falling off from the side wall of the pixel chip due to the poor adhesion between the bearing adhesive layer and the pixel chip, thereby improving the reliability of the light-emitting device.

Description

Technical Field

[0001] The present disclosure relates to the field of optoelectronic manufacturing technology, and in particular to a light-emitting device capable of improving the detachment of adhesive materials and a preparation method thereof. Background Art

[0002] In the emerging display field, Mini / Micro LED is constantly expanding the application boundaries of display screens. MIP (MicroLED in package) light-emitting devices realize the organic combination of Micro LED and discrete devices by packaging the entire large-area display panel separately.

[0003] In the related art, the light-emitting device of MIP includes a plurality of pixel chips and a carrier board, wherein the plurality of pixel chips are bonded to the carrier board by packaging adhesive, and a carrier adhesive layer is also provided on the carrier board to fill the gaps between the plurality of pixel chips.

[0004] However, aging of the supporting adhesive layer during use of the light-emitting device will cause the adhesion of the supporting adhesive layer to deteriorate, and stress will exist inside the light-emitting device, which will also cause the supporting adhesive layer to detach from the side wall of the pixel chip, thereby affecting the stability of the light-emitting device. Summary of the invention

[0005] The embodiments of the present disclosure provide a light-emitting device with improved adhesive detachment and a method for preparing the same, which can improve the problem of the adhesive layer falling off from the side wall of the pixel chip due to poor adhesion between the adhesive layer and the pixel chip, thereby improving the reliability of the light-emitting device. The technical solution is as follows:

[0006] An embodiment of the present disclosure provides a light-emitting device, which includes: a carrier board, a plurality of pixel chips and a supporting adhesive layer, wherein the plurality of pixel chips are arranged at intervals on the board surface of the carrier board; the supporting adhesive layer is located on the board surface of the carrier board and in the gaps between the plurality of pixel chips, and the supporting adhesive layer is connected to the side walls of the pixel chips, and at least a portion of the film layer of the supporting adhesive layer is a hollow structure.

[0007] In another implementation of the embodiment of the present disclosure, the supporting adhesive layer includes at least two adhesive layers stacked in sequence, the adhesive layer close to the carrier board has the hollow structure, and the adhesive layer far from the carrier board does not have the hollow structure.

[0008] In another implementation of the embodiment of the present disclosure, the thickness of the adhesive layer without the hollow structure in the adhesive layer is greater than or equal to 0.5 μm.

[0009] In another implementation of the embodiment of the present disclosure, the hollow structure includes at least one of a through hole and a blind hole.

[0010] In another implementation of the embodiment of the present disclosure, the hollow structure is a through hole, and at least some of the through holes in adjacent adhesive layers are interconnected.

[0011] In another implementation of the embodiment of the present disclosure, the hollow structure in the same adhesive layer is in a grid shape.

[0012] In another implementation of the embodiment of the present disclosure, at least one layer of the adhesive layers is a light blocking layer.

[0013] In another implementation of the embodiment of the present disclosure, the light-emitting device also includes a packaging glue layer, which is located on the board surface of the carrier, and the multiple pixel chips are arranged at intervals on the surface of the packaging glue layer away from the carrier; the supporting glue layer is also located on the surface of the packaging glue layer away from the carrier and covers the multiple pixel chips, and the supporting glue layer has a via hole exposing each of the pixel chips.

[0014] In another implementation of the embodiment of the present disclosure, the multiple pixel chips include: a first pixel chip, a second pixel chip and a third pixel chip, and the light-emitting colors of the first pixel chip, the second pixel chip and the third pixel chip are different; the light-emitting device also includes a first solder pad, a second solder pad, a third solder pad and a fourth solder pad, and the supporting glue layer exposes the first pixel chip, the second pixel chip and the third pixel chip; the first solder pad, the second solder pad, the third solder pad and the fourth solder pad are all located on the surface of the supporting glue layer away from the carrier board; the first electrode of the first pixel chip, the first electrode of the second pixel chip and the first electrode of the third pixel chip are all connected to the first solder pad; the second electrode of the first pixel chip is connected to the second solder pad, the second electrode of the second pixel chip is connected to the third solder pad, and the second electrode of the third solder pad is connected to the fourth solder pad.

[0015] An embodiment of the present disclosure provides a method for preparing a light-emitting device, the method comprising: transferring a plurality of pixel chips to the surface of a carrier board so that the plurality of pixel chips are arranged at intervals; forming a supporting adhesive layer on the surface of the carrier board, the supporting adhesive layer being located in the gaps between the plurality of pixel chips, and the supporting adhesive layer being connected to the side walls of the pixel chips, and at least a portion of the film layer of the supporting adhesive layer being a hollow structure.

[0016] The beneficial effects brought by the technical solution provided by the embodiments of the present disclosure include at least:

[0017] In the light-emitting device provided by the embodiment of the present disclosure, a plurality of pixel chips are arranged at intervals on a carrier board, and a bearing adhesive layer is also provided on the carrier board. The bearing adhesive layer is located in the gaps between the pixel chips and connects the side walls of each pixel chip to allow the pixel chips to be more stably fixed on the carrier board. Among them, at least part of the film layer of the bearing adhesive layer is a hollow structure, so that when the internal stress of the light-emitting device is transmitted to the position where the hollow structure is located, the stress will be interrupted, so that the stress of the light-emitting device can be released, so that the stress on the connection between the side wall of the pixel chip and the bearing adhesive layer is reduced, thereby preventing the bearing adhesive layer from falling off the side wall of the pixel chip and improving the stability of the light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a structural schematic diagram of a light-emitting device provided by the related technology;

[0020] Figure 2 is a top view of a light emitting device provided by an embodiment of the present disclosure;

[0021] Figure 3 is a schematic structural diagram of a light-emitting device provided by an embodiment of the present disclosure;

[0022] Figure 4 is a top view of another light emitting device provided by an embodiment of the present disclosure;

[0023] Figure 5 It is a flow chart of a method for preparing a light-emitting device provided in an embodiment of the present disclosure.

[0024] The descriptions of the marks in the figure are as follows:

[0025] 10. Carrier board;

[0026] 20. pixel chip; 21. first pixel chip; 22. second pixel chip; 23. third pixel chip; 24. concave hole;

[0027] 31. first pad; 32. second pad; 33. third pad; 34. fourth pad;

[0028] 41. a first electrode; 42. a second electrode;

[0029] 51, first conductive strip; 52, second conductive strip; 53, third conductive strip; 54, fourth conductive strip;

[0030] 60. Bearing rubber layer; 61. Hollow structure;

[0031] 70. Encapsulation adhesive layer. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0033] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons with ordinary skills in the field to which the present disclosure belongs. The words "first", "second", "third" and similar words used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate a quantity limitation, but indicate the existence of at least one. Words such as "include" or "comprise" and similar words mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right", "top", "bottom" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0034] Figure 1 It is a schematic diagram of the structure of a light emitting device provided by the related technology. Figure 1 As shown, the light-emitting device includes a plurality of pixel chips 20, a carrier board 10, a packaging glue and a supporting glue layer 60. The plurality of pixel chips 20 are bonded to the carrier board 10 by the packaging glue. The supporting glue layer 60 is located on the carrier board 10 and covers the packaging glue and the plurality of pixel chips, so that the supporting glue layer 60 fills the gaps between the plurality of pixel chips 20. The supporting glue layer 60 has vias that expose each pixel chip 20.

[0035] During the use of the light-emitting device, the aging of the supporting adhesive layer 60 may cause the adhesion of the supporting adhesive layer 60 to deteriorate. Figure 1 As shown in A, stress may exist inside the light emitting device, which may also cause the supporting adhesive layer 60 to be detached from the side wall of the pixel chip, thereby affecting the stability of the light emitting device.

[0036] To this end, an embodiment of the present disclosure provides a light emitting device. Figure 2 It is a top view of a light-emitting device provided by an embodiment of the present disclosure. Figure 3 Schematic diagram of a light emitting device provided by an embodiment of the present disclosure. Figure 2 , 3 As shown, the light emitting device comprises: a carrier board 10 , a plurality of pixel chips 20 and a carrier adhesive layer 60 , wherein the plurality of pixel chips 20 are arranged on the board surface of the carrier board 10 at intervals.

[0037] like Figure 2 , 3 As shown, the supporting adhesive layer 60 is located on the board surface of the carrier 10 and in the gaps between the plurality of pixel chips 20 , and the supporting adhesive layer 60 is connected to the sidewalls of the pixel chips 20 , and at least a portion of the film layer of the supporting adhesive layer 60 is a hollow structure 61 .

[0038] In the light-emitting device provided by the embodiment of the present disclosure, a plurality of pixel chips are arranged at intervals on a carrier board 10, and a carrying adhesive layer 60 is also provided on the carrier board 10. The carrying adhesive layer 60 is located in the gaps between the pixel chips and connects the side walls of each pixel chip, so that the pixel chips are more stably fixed on the carrier board 10. Among them, at least part of the film layer of the carrying adhesive layer 60 is a hollow structure 61, so that when the internal stress of the light-emitting device is transmitted to the position where the hollow structure 61 is located, the stress will be interrupted, so that the stress of the light-emitting device can be released, so that the stress on the connection between the side wall of the pixel chip and the carrying adhesive layer 60 is reduced, thereby preventing the carrying adhesive layer 60 from falling off the side wall of the pixel chip, and improving the stability of the light-emitting device.

[0039] Optionally, the supporting adhesive layer 60 includes at least two adhesive layers stacked in sequence, wherein the adhesive layer close to the carrier 10 has a hollow structure 61 , and the adhesive layer far from the carrier 10 has no hollow structure 61 .

[0040] In the embodiment of the present disclosure, the adhesive layer of the supporting adhesive layer 60 away from the carrier board 10 is set to have no hollow structure 61, so as to prevent the film material subsequently formed on the surface of the supporting adhesive layer 60 from being sunk into it. For example, when the conductive metal material is embedded in the hollow structure 61, the problem of short circuit of the pixel chip is likely to occur, thereby improving the safety of the light-emitting device.

[0041] At the same time, the adhesive layer in the supporting adhesive layer 60 close to the carrier 10 is set to have a hollow structure 61, so that when the stress inside the light-emitting device is transmitted to the adhesive layer in this area, the stress can be interrupted and released, thereby reducing the stress between the side wall of the pixel chip and the supporting adhesive layer 60.

[0042] In addition, a hollow structure 61 is provided in part of the adhesive layer in the supporting adhesive layer 60, so that the supporting adhesive layer 60 has a cavity, and different inner walls of the cavity can be used for reflection, so that the light emitted from the pixel chip can be reflected at the inner wall of the cavity, thereby improving the overall brightness of the light-emitting device.

[0043] As an example, in one implementation, the supporting adhesive layer 60 may include three adhesive layers stacked in sequence.

[0044] Exemplarily, the adhesive layer farthest from the carrier 10 is not provided with the hollow structure 61 , and the adhesive layer may be a silicon oxide layer, which is used to make the finally formed supporting adhesive layer 60 more planar.

[0045] Exemplarily, the two glue layers closest to the carrier 10 may be provided with hollow structures 61 to ensure that the number of hollow structures 61 is sufficient to release the internal stress of the light-emitting device.

[0046] Optionally, at least one of the adhesive layers is a light blocking layer.

[0047] Exemplarily, the light-blocking layer includes a silicon oxide layer and a black coating filled on the surface of the silicon oxide layer. The light-blocking layer is black so that most of the light entering the light-blocking layer is absorbed, thereby preventing the light from being emitted laterally to other pixel chips and causing light crosstalk.

[0048] Exemplarily, the light blocking layer may be a distributed Bragg reflector (DBR) layer, which can reflect light, thereby effectively blocking the light from being emitted laterally, avoiding the problem of light crosstalk and improving the brightness of the light emitting device.

[0049] The DBR layer includes multiple periodically alternately stacked SiO 2 Layer and TiO 2 The number of periods of the DBR layer may be between 20 and 50. For example, the number of periods of the DBR layer is 32.

[0050] Among them, SiO in the DBR layer 2 The thickness of the layer can be 800 angstroms to 1200 angstroms, TiO 2 The layer thickness may be 500 angstroms to 900 angstroms.

[0051] As an example, in one implementation, the supporting adhesive layer 60 may include three adhesive layers stacked in sequence.

[0052] Exemplarily, the middle glue layer of the three glue layers may be a light blocking layer.

[0053] Optionally, the thickness of the adhesive layer without the hollow structure 61 in the adhesive layer is greater than or equal to 0.5 μm.

[0054] By controlling the thickness of the adhesive layer without the hollow structure 61 within the above range, it is prevented that the adhesive layer without the hollow structure 61 is too thin and easily broken, causing the subsequent prepared film layer to enter the hollow structure 61 of the adhesive layer below. At the same time, it is also prevented that the adhesive layer without the hollow structure 61 is too thick and increases the thickness of the supporting adhesive layer 60, affecting the overall thickness of the light-emitting device.

[0055] Figure 4 FIG. 1 is a top view of another light emitting device provided by an embodiment of the present disclosure. Figure 4 As shown, the hollow structure 61 includes at least one of a through hole and a blind hole.

[0056] Exemplarily, the hollow structure 61 may be a through hole on the adhesive layer, and the through hole penetrates the adhesive layer. In two adjacent adhesive layers, if some through holes are opposite to each other, the opposite through holes are interconnected; if some through holes are misaligned, the misaligned through holes are not conductive.

[0057] For example, Figure 2 , 3 As shown, in the same glue layer, adjacent hollow structures 61 can be interconnected. In this way, the hollow structures 61 in the same glue layer are connected in series to form a cavity extending from one side of the glue layer to the other side, and the cavity also extends to the side wall of each pixel chip, which can effectively release the internal stress of the pixel chip.

[0058] Exemplarily, the shape of the through holes on the glue layer can be circular, elliptical or polygonal.

[0059] Alternatively, if Figure 2 As shown, the through holes on the adhesive layer are rectangular in shape, and the through holes in the same adhesive layer are interconnected, so that the hollow structure 61 in the same adhesive layer is grid-shaped. The grid-shaped hollow structure 61 can extend from one side of the adhesive layer to the other side, and the hollow structure 61 also extends to the side walls of each pixel chip, which can effectively release the internal stress of the pixel chip.

[0060] Alternatively, if Figure 3 As shown, the light emitting device further includes a packaging glue layer 70 , which is located on the board surface of the carrier 10 , and a plurality of pixel chips are arranged at intervals on the surface of the packaging glue layer 70 away from the carrier 10 .

[0061] like Figure 3 As shown, the supporting adhesive layer 60 is also located on the surface of the packaging adhesive layer 70 away from the carrier 10 and covers a plurality of pixel chips. The supporting adhesive layer 60 has vias exposing each pixel chip.

[0062] Exemplarily, the encapsulation glue layer 70 may be a silicon oxide layer, which can stably fix the pixel chip on the carrier 10 .

[0063] Alternatively, if Figure 3 As shown, the surface of the pixel chip close to the carrier 10 has a plurality of recessed holes 24 arranged at intervals.

[0064] By providing a plurality of recessed holes 24 arranged at intervals on the light-emitting surface of the pixel chip, the light-emitting surface of the pixel chip can be roughened, so that the encapsulation glue dripped on the light-emitting surface of the pixel chip can be hung on the light-emitting surface of the pixel chip. In particular, the encapsulation glue at the edge of the light-emitting surface of the pixel chip can be hung in the recessed holes 24 on the light-emitting surface of the pixel chip, thereby preventing the encapsulation glue from overflowing from the side wall of the pixel chip.

[0065] Optionally, the thickness of the encapsulation glue layer 70 is greater than or equal to the depth of the concave hole 24 and less than or equal to twice the thickness of the pixel chip.

[0066] The minimum thickness of the encapsulation layer 70 is set to be greater than or equal to the depth of the recessed hole 24 to ensure that the encapsulation layer 70 can fill the recessed hole 24 on the light-emitting surface of the pixel chip; at the same time, the maximum thickness of the encapsulation layer 70 is set to be less than or equal to twice the thickness of the pixel chip to prevent the encapsulation layer 70 from being too thick and absorbing more light.

[0067] For example, if the thickness of the pixel chip is 7 μm and the depth of the concave hole 24 is 1 μm, the minimum thickness of the encapsulation glue layer 70 should be greater than 1 μm and the maximum thickness of the encapsulation glue layer 70 should be less than 14 μm.

[0068] For example, the minimum thickness of the encapsulation glue layer 70 is 0.8 μm to 2 μm. The maximum thickness of the encapsulation glue layer 70 may be 1 / 3 to 2 times the thickness of the pixel chip.

[0069] Alternatively, if Figure 2 , 3 As shown, optionally, the plurality of pixel chips 20 include: a first pixel chip 21, a second pixel chip 22 and a third pixel chip 23, and the first pixel chip 21, the second pixel chip 22 and the third pixel chip 23 all emit light of different colors.

[0070] like Figure 2 As shown, the light emitting device further includes a first pad 31 , a second pad 32 , a third pad 33 and a fourth pad 34 , and the supporting adhesive layer 60 exposes the first pixel chip 21 , the second pixel chip 22 and the third pixel chip 23 .

[0071] like Figure 2 As shown, the first pad 31 , the second pad 32 , the third pad 33 and the fourth pad 34 are all located on the surface of the supporting adhesive layer 60 away from the carrier 10 .

[0072] like Figure 2 As shown, the first electrode 41 of the first pixel chip 21 , the first electrode 41 of the second pixel chip 22 , and the first electrode 41 of the third pixel chip 23 are all connected to the first pad 31 .

[0073] In this way, the first pad 31 is connected to the first electrode 41 of each pixel chip, and the first pad 31 is used as a common pad, thereby avoiding setting more pads on the flat layer, so as to reduce the size of the light-emitting device.

[0074] like Figure 2 As shown, the second electrode 42 of the first pixel chip 21 is connected to the second pad 32 , the second electrode 42 of the second pixel chip 22 is connected to the third pad 33 , and the second electrode 42 of the third pad 33 is connected to the fourth pad 34 .

[0075] In the disclosed embodiment, a pad is separately provided for each pixel chip, and whether the pixel chip emits light can be controlled by controlling the pad corresponding to the pixel chip to be energized.

[0076] Alternatively, if Figure 2 As shown, the light emitting device further includes: a first conductive strip 51 , a second conductive strip 52 , a third conductive strip 53 and a fourth conductive strip 54 .

[0077] like Figure 2 As shown, one end of the first conductive strip 51 is connected to the first pad 31 , and the first electrode 41 of each pixel chip is connected to the first conductive strip 51 .

[0078] like Figure 2 As shown, one end of the second conductive strip 52 is connected to the second pad 32 , and the other end of the second conductive strip 52 is connected to the second electrode 42 of the first pixel chip 21 .

[0079] like Figure 2 As shown, one end of the third conductive strip 53 is connected to the third pad 33 , and the other end of the third conductive strip 53 is connected to the second electrode 42 of the second pixel chip 22 .

[0080] like Figure 2 As shown, one end of the fourth conductive strip 54 is connected to the fourth pad 34 , and the other end of the fourth conductive strip 54 is connected to the second electrode 42 of the third pixel chip 23 .

[0081] In the embodiment of the present disclosure, the plurality of pixel chips include a first pixel chip 21 emitting red light, a second pixel chip 22 emitting green light, and a third pixel chip 23 emitting blue light.

[0082] The difference between the first pixel chip 21 , the second pixel chip 22 and the third pixel chip 23 is that the light-emitting colors of the epitaxial layers are different.

[0083] For the first pixel chip 21, the epitaxial layer is a red epitaxial layer. For the second pixel chip 22, the epitaxial layer is a green epitaxial layer. For the third pixel chip 23, the epitaxial layer is a blue epitaxial layer.

[0084] The red light epitaxial layer includes a first p-type layer, a first light-emitting layer and a first n-type layer stacked in sequence.

[0085] In the red epitaxial layer, the first p-type layer includes a p-type AlInP layer.

[0086] The first light-emitting layer includes an AlGaInP quantum well layer and an AlGaInP quantum barrier layer grown alternately, wherein the Al content in the AlGaInP quantum well layer and the AlGaInP quantum barrier layer is different. The first light-emitting layer may include 3 to 8 periods of AlGaInP quantum well layers and AlGaInP quantum barrier layers stacked alternately.

[0087] The first n-type layer includes an n-type AlGaInP current spreading layer.

[0088] In the embodiment of the present disclosure, the green epitaxial layer includes a second p-type layer, a second light-emitting layer, and a second n-type layer stacked in sequence.

[0089] In the green epitaxial layer, the second p-type layer includes a p-type GaN layer.

[0090] The second light-emitting layer includes alternately grown InGaN quantum well layers and GaN quantum barrier layers. The second light-emitting layer may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0091] The second n-type layer includes an n-type GaN layer.

[0092] In the disclosed embodiment, the blue light epitaxial layer includes a third p-type layer, a third light-emitting layer and a third n-type layer stacked in sequence.

[0093] In the blue epitaxial layer, the third p-type layer includes a p-type GaN layer.

[0094] The third light emitting layer may include alternately grown InGaN quantum well layers and GaN quantum barrier layers. The third light emitting layer may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0095] The third n-type layer includes an n-type GaN layer.

[0096] Optionally, the thickness of the pixel chip is 2 μm to 10 μm.

[0097] Exemplarily, the thickness of the red epitaxial layer is 5 μm, the thickness of the green epitaxial layer is 8 μm, and the thickness of the blue epitaxial layer is 6 μm.

[0098] By way of example, the carrier 10 may be a sapphire substrate or a glass substrate.

[0099] In the disclosed embodiment, the first electrode 41 of each pixel chip is connected to the n-type layer, and the second electrode 42 of each pixel chip is connected to the p-type layer. The first electrode 41 is connected to the first pad 31, so the first pad 31 is a negative pad, and correspondingly, the second pad 32, the third pad 33 and the fourth pad 34 are all positive pads.

[0100] Figure 5 FIG. 1 is a flow chart of a method for preparing a light-emitting device provided in an embodiment of the present disclosure. Figure 5 As shown, the preparation method comprises:

[0101] Step 101: Transfer a plurality of pixel chips to the surface of a carrier 10 so that the plurality of pixel chips are arranged at intervals.

[0102] Step 102 : forming a carrier adhesive layer 60 on the surface of the carrier 10 .

[0103] The supporting adhesive layer 60 is located in the gaps between the plurality of pixel chips, and the supporting adhesive layer 60 is connected to the sidewalls of the pixel chips. At least a portion of the film layer of the supporting adhesive layer 60 is a hollow structure 61 .

[0104] In the light-emitting device prepared in the embodiment of the present disclosure, a plurality of pixel chips are arranged at intervals on a carrier board 10, and a carrying adhesive layer 60 is also provided on the carrier board 10. The carrying adhesive layer 60 is located in the gaps between the pixel chips and connects the side walls of each pixel chip, so that the pixel chips are more stably fixed on the carrier board 10. Among them, at least part of the film layer of the carrying adhesive layer 60 is a hollow structure 61, so that when the internal stress of the light-emitting device is transmitted to the position where the hollow structure 61 is located, the stress will be interrupted, so that the stress of the light-emitting device can be released, so that the stress on the connection between the side wall of the pixel chip and the carrying adhesive layer 60 is reduced, thereby preventing the carrying adhesive layer 60 from falling off the side wall of the pixel chip, and improving the stability of the light-emitting device.

[0105] Step 101 may include the following steps:

[0106] First, a plurality of recessed holes 24 arranged at intervals are formed on the light emitting surface of the pixel chip.

[0107] A plurality of concave holes 24 are formed on the light-emitting surface of the pixel chip, thereby roughening the light-emitting surface of the pixel chip, so that the packaging glue dripped on the light-emitting surface of the pixel chip can hang on the light-emitting surface of the pixel chip. In particular, the packaging glue at the edge of the light-emitting surface of the pixel chip can be hung in the concave holes 24 on the light-emitting surface of the pixel chip, thereby preventing the packaging glue from overflowing from the side wall of the pixel chip.

[0108] Optionally, after the concave hole 24 is formed on the light-emitting surface of the pixel chip, the method may further include: treating the light-emitting surface of the pixel chip by plasma bombardment to clean the light-emitting surface of the pixel chip.

[0109] Then, the packaging glue is dropped onto the light-emitting surface of the pixel chip by using inkjet printing technology, so that the packaging glue X fills the concave hole 24 .

[0110] The use of inkjet printing technology can well control the amount of encapsulation glue dripping on the light-emitting surface of the pixel chip, avoiding the problem of too much or too little encapsulation glue dripping on the light-emitting surface of the pixel chip. In addition, the encapsulation glue dripped by the inkjet printing technology is in the form of droplets, which is easier to fill the concave hole 24 on the light-emitting surface of the pixel chip.

[0111] Exemplarily, the packaging glue may be liquid silicone.

[0112] Next, the packaging glue is pre-cured to make the packaging glue sticky.

[0113] For example, the encapsulation glue may be pre-cured by heating or irradiation with ultraviolet light, so that the surface of the encapsulation glue has a certain viscosity, thereby bonding the pixel chip and the carrier board 10 .

[0114] Exemplarily, the duration of heating or UV light irradiation may be 2 minutes to 10 minutes.

[0115] Then, a plurality of pixel chips are arranged on the carrier 10 by mass transfer, so that the packaging glue adheres to the carrier 10 .

[0116] By way of example, the carrier 10 may be a sapphire substrate or a glass substrate.

[0117] Alternatively, if Figure 2 As shown, the plurality of pixel chips include a first pixel chip 21, a second pixel chip 22 and a third pixel chip 23, and the first pixel chip 21, the second pixel chip 22 and the third pixel chip 23 emit light of different colors.

[0118] In the disclosed embodiment, the first pixel chip 21 may be a pixel chip that emits red light, the second pixel chip 22 may be a pixel chip that emits green light, and the third pixel chip 23 may be a pixel chip that emits blue light.

[0119] In the disclosed embodiment, each pixel chip includes an epitaxial layer, a passivation layer and an electrode. The epitaxial layer is located on the surface of the substrate, and the epitaxial layer includes a p-type layer, a light-emitting layer and an n-type layer stacked in sequence, the n-type layer has a groove exposing the p-type layer, the passivation layer is located on the surface of the n-type layer and in the groove, and the passivation layer has a through hole exposing the n-type layer and the groove.

[0120] The surface of the passivation layer is provided with a first electrode 41 and a second electrode 42 , and the first electrode 41 and the second electrode 42 are connected to the n-type layer and the p-type layer through two through holes, respectively.

[0121] In the embodiment of the present disclosure, the plurality of pixel chips include a first pixel chip 21 emitting red light, a second pixel chip 22 emitting green light, and a third pixel chip 23 emitting blue light.

[0122] The difference between the first pixel chip 21 , the second pixel chip 22 and the third pixel chip 23 is that the light-emitting colors of the epitaxial layers are different.

[0123] For the first pixel chip 21, the epitaxial layer is a red epitaxial layer. For the second pixel chip 22, the epitaxial layer is a green epitaxial layer. For the third pixel chip 23, the epitaxial layer is a blue epitaxial layer.

[0124] The red light epitaxial layer includes a first p-type layer, a first light-emitting layer and a first n-type layer stacked in sequence.

[0125] In the red epitaxial layer, the first p-type layer includes a p-type AlInP layer.

[0126] The first light-emitting layer includes an AlGaInP quantum well layer and an AlGaInP quantum barrier layer grown alternately, wherein the Al content in the AlGaInP quantum well layer and the AlGaInP quantum barrier layer is different. The first light-emitting layer may include 3 to 8 periods of AlGaInP quantum well layers and AlGaInP quantum barrier layers stacked alternately.

[0127] The first n-type layer includes an n-type AlGaInP current spreading layer.

[0128] In the embodiment of the present disclosure, the green epitaxial layer includes a second p-type layer, a second light-emitting layer, and a second n-type layer stacked in sequence.

[0129] In the green epitaxial layer, the second p-type layer includes a p-type GaN layer.

[0130] The second light-emitting layer includes alternately grown InGaN quantum well layers and GaN quantum barrier layers. The second light-emitting layer may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0131] The second n-type layer includes an n-type GaN layer.

[0132] In the disclosed embodiment, the blue light epitaxial layer includes a third p-type layer, a third light-emitting layer and a third n-type layer stacked in sequence.

[0133] In the blue epitaxial layer, the third p-type layer includes a p-type GaN layer.

[0134] The third light emitting layer may include alternately grown InGaN quantum well layers and GaN quantum barrier layers. The third light emitting layer may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0135] The third n-type layer includes an n-type GaN layer.

[0136] Optionally, the thickness of the pixel chip is 2 μm to 10 μm.

[0137] Exemplarily, the thickness of the red epitaxial layer is 5 μm, the thickness of the green epitaxial layer is 8 μm, and the thickness of the blue epitaxial layer is 6 μm.

[0138] Step 102 may include: forming multiple layers of adhesive material on the carrier 10 in sequence.

[0139] When preparing the glue layer close to the carrier 10 , the glue layer needs to be etched to form a hollow structure 61 on the glue layer.

[0140] Optionally, the supporting adhesive layer 60 includes at least two adhesive layers stacked in sequence, wherein the adhesive layer close to the carrier 10 has a hollow structure 61 , and the adhesive layer far from the carrier 10 has no hollow structure 61 .

[0141] As an example, in one implementation, the supporting adhesive layer 60 may include three adhesive layers stacked in sequence.

[0142] Exemplarily, the adhesive layer farthest from the carrier 10 is not provided with the hollow structure 61 , and the adhesive layer may be a silicon oxide layer, which is used to make the finally formed supporting adhesive layer 60 more planar.

[0143] Exemplarily, the two glue layers closest to the carrier 10 may be provided with hollow structures 61 to ensure that the number of hollow structures 61 is sufficient to release the internal stress of the light-emitting device.

[0144] Optionally, at least one of the adhesive layers is a light blocking layer.

[0145] Exemplarily, the light-blocking layer includes a silicon oxide layer and a black coating filled on the surface of the silicon oxide layer. The light-blocking layer is black so that most of the light entering the light-blocking layer is absorbed, thereby preventing the light from being emitted laterally to other pixel chips and causing light crosstalk.

[0146] As an example, in one implementation, the supporting adhesive layer 60 may include three adhesive layers stacked in sequence.

[0147] Exemplarily, the middle glue layer of the three glue layers may be a light blocking layer.

[0148] Optionally, the thickness of the adhesive layer without the hollow structure 61 in the adhesive layer is greater than or equal to 0.5 μm.

[0149] Alternatively, if Figure 2As shown, the through holes on the adhesive layer are rectangular in shape, and the through holes in the same adhesive layer are interconnected, so that the hollow structure 61 in the same adhesive layer is in a grid shape.

[0150] After step 102 , the following steps may further include: making a pad and a conductive strip on the surface of the supporting adhesive layer 60 , wherein one end of the conductive strip is connected to the pixel chip, and the other end of the conductive strip is connected to the pad.

[0151] Optionally, the light emitting device further includes: a first pad 31 , a second pad 32 , a third pad 33 and a fourth pad 34 . The supporting adhesive layer 60 exposes the first pixel chip 21 , the second pixel chip 22 and the third pixel chip 23 .

[0152] like Figure 3 As shown, the first pad 31 , the second pad 32 , the third pad 33 and the fourth pad 34 are all located on the surface of the supporting adhesive layer 60 away from the carrier 10 .

[0153] like Figure 3 As shown, the first electrode 41 of the first pixel chip 21 , the first electrode 41 of the second pixel chip 22 , and the first electrode 41 of the third pixel chip 23 are all connected to the first pad 31 .

[0154] In this way, the first pad 31 is connected to the first electrode 41 of each pixel chip, and the first pad 31 is used as a common pad, thereby avoiding setting more pads on the flat layer, so as to reduce the size of the light-emitting device.

[0155] like Figure 3 As shown, the second electrode 42 of the first pixel chip 21 is connected to the second pad 32 , the second electrode 42 of the second pixel chip 22 is connected to the third pad 33 , and the second electrode 42 of the third pad 33 is connected to the fourth pad 34 .

[0156] In the disclosed embodiment, a pad is separately provided for each pixel chip, and whether the pixel chip emits light can be controlled by controlling the pad corresponding to the pixel chip to be energized.

[0157] Alternatively, if Figure 2 As shown, the light emitting device further includes: a first conductive strip 51 , a second conductive strip 52 , a third conductive strip 53 and a fourth conductive strip 54 .

[0158] like Figure 2 As shown, one end of the first conductive strip 51 is connected to the first pad 31 , and the first electrode 41 of each pixel chip is connected to the first conductive strip 51 .

[0159] like Figure 2 As shown, one end of the second conductive strip 52 is connected to the second pad 32 , and the other end of the second conductive strip 52 is connected to the second electrode 42 of the first pixel chip 21 .

[0160] like Figure 2 As shown, one end of the third conductive strip 53 is connected to the third pad 33 , and the other end of the third conductive strip 53 is connected to the second electrode 42 of the second pixel chip 22 .

[0161] like Figure 2 As shown, one end of the fourth conductive strip 54 is connected to the fourth pad 34 , and the other end of the fourth conductive strip 54 is connected to the second electrode 42 of the third pixel chip 23 .

[0162] An embodiment of the present disclosure provides a display panel, which includes a plurality of light-emitting devices, a driver integrated circuit (IC) and a circuit board as described above, wherein the plurality of light-emitting devices and the driver IC are both located on the circuit board.

[0163] Exemplarily, a plurality of light emitting device arrays are arranged on a circuit board.

[0164] The driver IC is located on the circuit board and is electrically connected to the driving wires on the circuit board, and the solder joints of the plurality of light emitting devices are also electrically connected to the driving wires on the circuit board. In this way, the driver IC can control each light emitting device through the driving wires.

[0165] The above does not limit the present disclosure in any form. Although the present disclosure has been disclosed as above through the embodiments, it is not used to limit the present disclosure. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present disclosure. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present disclosure without departing from the content of the technical solution of the present disclosure still falls within the scope of the technical solution of the present disclosure.

Claims

1. A light emitting device, characterized in that: The light-emitting device comprises: a carrier board (10), a plurality of pixel chips (20) and a carrier adhesive layer (60), wherein the plurality of pixel chips (20) are arranged at intervals on the board surface of the carrier board (10); The supporting adhesive layer (60) is located on the board surface of the carrier board (10) and in the gaps between the plurality of pixel chips (20), and the supporting adhesive layer (60) is connected to the side walls of the pixel chips (20), the supporting adhesive layer (60) comprises at least two adhesive layers stacked in sequence, the adhesive layer close to the carrier board (10) has a hollow structure (61), and the adhesive layer far from the carrier board (10) does not have the hollow structure (61); The hollow structure (61) in the same glue layer is in a grid shape, and in a direction parallel to the carrier (10), the hollow structure (61) extends from one side of the glue layer to the other side, and the hollow structure (61) also extends to the side wall of each pixel chip (20).

2. The light emitting device according to claim 1, characterized in that: The thickness of the adhesive layer without the hollow structure (61) in the adhesive layer is greater than or equal to 0.5 μm.

3. The light emitting device according to claim 1 or 2, characterized in that: The hollow structure (61) comprises at least one of a through hole and a blind hole.

4. The light emitting device according to claim 3, characterized in that: The hollow structure (61) is a through hole, and at least some of the through holes in adjacent adhesive layers are interconnected.

5. The light emitting device according to claim 1 or 2, characterized in that: At least one of the adhesive layers is a light blocking layer.

6. The light emitting device according to claim 1 or 2, characterized in that: The light-emitting device further comprises an encapsulation adhesive layer (70), the encapsulation adhesive layer (70) being located on a surface of the carrier board (10), and the plurality of pixel chips (20) being arranged at intervals on a surface of the encapsulation adhesive layer (70) away from the carrier board (10); The supporting adhesive layer (60) is also located on a surface of the packaging adhesive layer (70) away from the carrier board (10) and covers a plurality of the pixel chips (20), and the supporting adhesive layer (60) has a via hole exposing each of the pixel chips (20).

7. The light emitting device according to claim 1 or 2, characterized in that: The plurality of pixel chips (20) comprise: a first pixel chip (21), a second pixel chip (22) and a third pixel chip (23), wherein the first pixel chip (21), the second pixel chip (22) and the third pixel chip (23) all emit different colors of light; The light-emitting device further comprises a first solder pad (31), a second solder pad (32), a third solder pad (33) and a fourth solder pad (34); the supporting adhesive layer (60) exposes the first pixel chip (21), the second pixel chip (22) and the third pixel chip (23); The first solder pad (31), the second solder pad (32), the third solder pad (33) and the fourth solder pad (34) are all located on a surface of the supporting adhesive layer (60) away from the carrier board (10); The first electrode (41) of the first pixel chip (21), the first electrode (41) of the second pixel chip (22), and the first electrode (41) of the third pixel chip (23) are all connected to the first pad (31); The second electrode (42) of the first pixel chip (21) is connected to the second pad (32), the second electrode (42) of the second pixel chip (22) is connected to the third pad (33), and the second electrode (42) of the third pad (33) is connected to the fourth pad (34).

8. A method for preparing a light emitting device, characterized in that: The preparation method comprises: Transferring a plurality of pixel chips onto the surface of a carrier board so that the plurality of pixel chips are arranged at intervals; A carrying glue layer is formed on the surface of the carrier board, the carrying glue layer is located in the gap between the plurality of pixel chips, and the carrying glue layer is connected to the side walls of the pixel chips, the carrying glue layer includes at least two glue layers stacked in sequence, the glue layer close to the carrier board has a hollow structure, and the glue layer far from the carrier board does not have the hollow structure; the hollow structure in the same glue layer is in a grid shape, and in a direction parallel to the carrier board, the hollow structure extends from one side of the glue layer to the other side, and the hollow structure also extends to the side walls of each pixel chip.

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