DISPLAY DEVICE AND MANUFACTURING METHOD THEREOF

Abstract

Display device (10, 20), which includes: a circuit substrate (100); a first light-emitting diode (300) located above the circuit substrate (100); an anisotropic conductive adhesive structure (212, 212a, 212b) located between the circuit substrate (100) and the first light-emitting diode (300) and electrically connecting the circuit substrate (100) to a lower electrode (310) of the first light-emitting diode (300), wherein, taking a top surface (100t) of the circuit substrate (100) as a reference, a height of a top surface (212t) of the anisotropic conductive adhesive structure (212, 212a, 212b) is greater than or equal to a height of a top surface (330t) of a light-emitting layer (330) of the first light-emitting diode (300), and the height of the top surface (212t) of the anisotropic conductive adhesive structure (212, 212a, 212b) is less than a height of a top surface (330t) of the first light-emitting diode (300). electrode (350) of the first light-emitting diode (300) is; and a conductive connecting element (800) that electrically connects the upper electrode (350) of the first light-emitting diode (300) to the circuit substrate (100), wherein part of the conductive connecting element (800) is located on the anisotropic conductive adhesive structure (212, 212a, 212b).

Description

BACKGROUND Technical area

[0001] The disclosure relates to a display device and a manufacturing process thereof. Description of the state of the art

[0002] A light-emitting diode (LED) is an electroluminescent semiconductor device and exhibits high efficiency, long lifespan, fracture resistance, fast response time, high reliability, and other properties. The technology for manufacturing a micro-LED display generally involves transferring a large number of micro-LEDs onto a pixel array substrate. The micro-LEDs are typically electrically bonded to the pixel array substrate using solder. However, the solder-bonded micro-LEDs can detach due to heat or shock during subsequent processes (e.g., conductive bonding), leading to micro-LED failure during normal operation.

[0003] WO 2012 / 093548 A1 discloses a film-forming pattern-making process comprising the following steps: capturing an image of the entirety of a conductor frame on which a plurality of LED chips are installed, within a camera's field of view, and recognizing the positions of the conductor of the conductor frame and each LED chip from the captured image; generating, based on the results of the recognition, a render file for a slanted-plane resin, which designates positions where a slanted-plane resin pattern is formed extending downwards from the top of the side face of each LED chip towards the lead-in, a render file for a wiring substrate, which designates positions where a wiring substrate pattern is formed on the slanted-plane resin pattern, and a render file for the wiring, which designates positions where a wiring pattern is formed.

[0004] US 2006 / 0103000A1 discloses a housing for an electronic component, comprising a substrate on which an electronic component is mounted, a plurality of component electrodes formed on an electronic component, a plurality of substrate electrodes formed on the substrate, and a plurality of connecting leads formed by a liquid droplet ejection process, each of which electrically connects one of the plurality of component electrodes and one of the plurality of substrate electrodes.

[0005] DE 10 2013 201 926 A1 discloses a method for electrically contacting a component, wherein the component is arranged on a circuit carrier which has a first connection area, wherein the first connection area is connected to a second connection area of ​​the component by means of an electrically conductive layer. BRIEF SUMMARY OF THE INVENTION

[0006] The disclosure relates to a display device and a manufacturing process thereof, which are adapted to reduce the probability of light-emitting diode failure and to reduce the manufacturing difficulties of a conductive connecting element.

[0007] At least one embodiment of the disclosure provides a display device comprising a circuit substrate, a first light-emitting diode, an anisotropic conductive adhesive structure, and a conductive connecting element. The first light-emitting diode is located above the circuit substrate. The anisotropic conductive adhesive structure is located between the circuit substrate and the first light-emitting diode and electrically connects the circuit substrate to a lower electrode of the first light-emitting diode. Taking an upper surface of the circuit substrate as a reference, the height of an upper surface of the anisotropic conductive adhesive structure is greater than or equal to the height of an upper surface of a light-emitting layer of the first light-emitting diode, and the height of the upper surface of the anisotropic conductive adhesive structure is less than the height of an upper electrode of the first light-emitting diode.The conductive connecting element electrically connects the upper electrode of the first light-emitting diode to the circuit substrate. A section of the conductive connecting element is located on the anisotropic conductive adhesive structure.

[0008] At least one embodiment of the disclosure provides a manufacturing method for a display device comprising the following: An anisotropic conductive adhesive structure is applied over a circuit substrate. A first light-emitting diode is positioned over the circuit substrate. The anisotropic conductive adhesive structure is located between the circuit substrate and the first light-emitting diode. The first light-emitting diode is pressurized so that it is enclosed within the anisotropic conductive adhesive structure.Taking the top surface of the circuit substrate as a reference, the height of a top surface of the anisotropic conductive adhesive structure is greater than or equal to the height of a top surface of a light-emitting layer of the first light-emitting diode, and the height of the top surface of the anisotropic conductive adhesive structure is less than the height of a top electrode of the first light-emitting diode. The anisotropic conductive adhesive structure electrically connects the circuit substrate to a bottom electrode of the first light-emitting diode. A conductive connecting element is formed on the top electrode of the first light-emitting diode, the anisotropic conductive adhesive structure, and the circuit substrate. This conductive connecting element electrically connects the top electrode of the first light-emitting diode to the circuit substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings serve to further understand the revelation and are an integral part of this description. The drawings illustrate embodiments of the revelation and, together with the description, serve to explain the principles of the revelation. Fig. 1A to Fig. Figure 1G are schematic cross-sectional views of a manufacturing process for a display device according to an embodiment of the disclosure. Fig. 2A to Fig. Figures 2G are schematic cross-sectional views of a manufacturing process for a display device according to an embodiment of the disclosure. Fig. Figure 3 is a schematic cross-sectional view of a manufacturing process for a display device according to an embodiment of the disclosure. Fig. Figure 4 is a schematic cross-sectional view of a manufacturing process for a display device according to an embodiment of the disclosure. Fig. Figure 5 is a schematic cross-sectional view of an anisotropic conductive adhesive structure before pressure is applied according to an embodiment of the disclosure. Fig. Figure 6 is a schematic cross-sectional view of an anisotropic conductive adhesive structure before pressurization according to an embodiment of the disclosure. DESCRIPTION OF THE EXECUTION FORMS

[0010] Fig. 1A to Fig. Figure 1G are schematic cross-sectional views of a manufacturing process for a display device according to an embodiment of the disclosure. With reference to Fig. 1A to Fig. In 1C, a plurality of anisotropic conductive adhesive structures 212, separated from one another, are arranged on a circuit substrate 100. For example, an anisotropic conductive adhesive layer 210 is first applied to the entire surface of a carrier plate 200, as in Fig. 1A is shown. Then the carrier plate 200 and the anisotropic conductive adhesive layer 210 are shown according to Fig. 1B is moved to the top of the circuit substrate 100, and a section of the anisotropic conductive adhesive layer 210 is irradiated with the laser LS. After irradiation with the laser LS, a section of the anisotropic conductive adhesive layer 210 is transferred to the circuit substrate 100 to form the anisotropic conductive adhesive structures 212, as shown in Fig. 1B to Fig. Figure 1C shows that in this embodiment the laser LS is used to control the size and shape of the anisotropic conductive adhesive structures 212 to be transferred to the circuit substrate 100, and after the anisotropic conductive adhesive structures 212 have been transferred to the circuit substrate 100, a section of the anisotropic conductive adhesive layer 210 remains on the carrier plate 200.

[0011] In some embodiments, the anisotropic conductive adhesive structures 212 are transparent. In other embodiments, the anisotropic conductive adhesive structures 212 can be gray or black due to the addition of a carbon black material. When the carbon black material is added to the anisotropic conductive adhesive structures 212, they can be used as an anti-reflective layer to reduce the reflectivity of a display area of ​​the display device.

[0012] In this embodiment, an area of ​​the circuit substrate 100 contains a plurality of first pads 102 and a plurality of second pads 104. The interior of the circuit substrate 100 also contains further circuit structures (not shown), and the arrangement of the circuit structures can be adapted as required. In this embodiment, a corresponding anisotropic conductive adhesive structure 212 is arranged on each of the first pads 102.

[0013] Then, referring to Fig. In 1D, a plurality of first light-emitting diodes (LEDs) 300 are arranged over the circuit substrate 100, wherein the anisotropic conductive adhesive structures 212 are located between the circuit substrate 100 and the first LEDs 300.

[0014] For example, the plurality of first LEDs 300 is initially formed on a growth substrate (not shown). In the embodiment, the first LEDs 300 are vertical LEDs, and each first LED 300 comprises a lower electrode 310, a first semiconductor layer 320, a light-emitting layer 330, a second semiconductor layer 340, and an upper electrode 350, which are stacked sequentially, wherein one of the first semiconductor layer 320 and one of the second semiconductor layer 340 is an N-type semiconductor and the other is a P-type semiconductor.

[0015] Then the first LEDs 300 on the growth substrate are transferred to a transfer substrate 400. For example, the first LEDs 300 are glued to an adhesive layer 410 of the transfer substrate 400.

[0016] The transfer substrate 400 is then used to transfer the first LEDs 300 onto the circuit substrate 100, and the anisotropic conductive adhesive structures 212 are adhered to the first LEDs 300. The adhesive force between the first LEDs 300 and the anisotropic conductive adhesive structures 212 is greater than the adhesive force between the first LEDs 300 and the adhesive layer 410. Therefore, after the transfer substrate 400 has been removed, the first LEDs 300 can remain on the anisotropic conductive adhesive structures 212, with each anisotropic conductive adhesive structure 212 positioned between the circuit substrate 100 and the corresponding first LED 300.

[0017] Then, in relation to Fig. 1E to Fig. In 1F, the first LEDs 300 are pressurized so that they are enclosed within the anisotropic, conductive adhesive structures 212. For example, a pressurizing element 500 is used to pressurize the plurality of first LEDs 300 simultaneously. In some embodiments, one area of ​​the pressurizing element 500 includes a buffer layer 510, and the buffer layer 510 contacts the plurality of first LEDs 300 simultaneously.

[0018] After the first LEDs 300 are subjected to pressure, the height of an upper surface 212t of the anisotropic conductive adhesive structure 212 is greater than or equal to the height of an upper surface 330t of the light-emitting layer 330 of the first LED 300, and the height of the upper surface 212t of the anisotropic conductive adhesive structure 212 is less than the height of the upper electrode 350 of the first LED 300 when considering an upper surface 100t of the circuit substrate 100a as a reference. Therefore, the anisotropic conductive adhesive structure 212 covers a side wall of the lower electrode 310, a side wall of the first semiconductor layer 320, and a side wall of the light-emitting layer 330. Based on the above description, a short circuit between a subsequently formed conductive connection element and the lower electrode 310 or the first semiconductor layer 320 can be avoided.

[0019] In some embodiments, the anisotropic conductive adhesive structure 212 can wrap around the lower electrode 310, the first semiconductor layer 320, and the light-emitting layer 330 after pressurization by adjusting the thickness T1 and width W1 of the anisotropic conductive adhesive structure 212 before pressurization (see Fig. 1E). For example, in some embodiments, the thickness T1 of the anisotropic conductive adhesive structure 212 before pressurization is greater than the thickness T2 of the lower electrode 310 of the first LED 300. In some embodiments, the width W1 of the anisotropic conductive adhesive structure 212 is greater than the width W2 of the first LED 300.

[0020] After the first LED 300 is pressurized, the anisotropic conductive adhesive structure 212 electrically connects the first pad 102 of the circuit substrate 100 to the lower electrode 310 of the first LED 300. In this embodiment, the anisotropic conductive adhesive structure 212 can conduct electricity in a direction F of the pressure after pressurization, such as the direction F perpendicular to the upper surface 100t of the circuit substrate 100. Fig. 1F.

[0021] In this embodiment, the use of the anisotropic, conductive adhesive structures 212 for bonding the first LEDs 300 to the circuit substrate 100 can reduce the probability of the first LEDs 300 dropping.

[0022] In some embodiments, the anisotropic conductive adhesive structures 212 are heated while the first LEDs 300 are pressurized to cure the anisotropic conductive adhesive structures 212. In some embodiments, the anisotropic conductive adhesive structures 212 are heated to a temperature of 100°C to 180°C to cure the anisotropic conductive adhesive structures 212.

[0023] Finally, in Fig. 1G a plurality of conductive connecting elements 800 are formed on the upper electrode 350 of the first LEDs 300, the anisotropic conductive adhesive structures 212 and the second pads 104 of the circuit substrate 100. A section of the conductive connecting element 800 is located on the anisotropic conductive adhesive structure 212. The conductive connecting element 800 electrically connects the upper electrode 350 of the first LED 300 to the second pad 104 of the circuit substrate 100.The conductive connecting element 800 is in contact with the upper electrode 350, the second semiconductor layer 340, the conductive connecting element 800 and the second pad 104, and a section of the anisotropic conductive adhesive structure 212 is enclosed between the conductive connecting element 800 and the light-emitting layer 330, between the conductive connecting element 800 and the first semiconductor layer 320, between the conductive connecting element 800 and the lower electrode 310, and between the conductive connecting element 800 and the first pad 102. In some embodiments, the conductive connecting element 800 comprises metal, metal oxide (e.g., indium tin oxide), metal nitride, or other suitable materials.Since the anisotropic conductive adhesive structure 212 in the embodiment does not conduct electricity in the horizontal direction H, the conductive connecting element 800, even when it contacts a side wall 212s of the anisotropic conductive adhesive structure 212, is not short-circuited with the first semiconductor layer 320 or the first pad 102.

[0024] In this embodiment, the anisotropic conductive adhesive structure 212 can be used as a step to prevent the conductive connecting element 800 from breaking due to an excessive step difference between the upper electrode 350 and the second pad 104, thereby reducing the manufacturing difficulties of the conductive connecting elements 800.

[0025] In this embodiment, a display device 10 comprises the circuit substrate 100, the first LEDs 300, the anisotropic conductive adhesive structures 212, and the conductive connecting elements 800. In some embodiments, since the display device 10 contains a plurality of anisotropic conductive adhesive structures 212 that are separated from one another, a transparent area that does not contain the anisotropic conductive adhesive structures 212 can be incorporated into the display device 10 to make the display device 10 transparent. Compared to forming an anisotropic conductive film over the entire surface of the circuit substrate 100, the area of ​​the transparent region of the transparent display device can be increased by forming the plurality of anisotropic conductive adhesive structures 212 that are separated from one another.

[0026] Fig. 2A to Fig. Figures 2G are schematic cross-sectional views of a manufacturing process for a display device according to an embodiment of the disclosure. It should be noted that the embodiment of Fig. 2A to Fig. 2G continues to include the reference numerals of the components and part of the content of the embodiment of Fig. 1A to Fig. 1G is used, where the same reference numerals denote the same or similar components and descriptions of the same technical content are omitted. For the descriptions of the omitted parts, reference may be made to the aforementioned embodiment, and its detailed descriptions are not repeated in the following embodiment. Referring to Fig. In embodiment 2A, a second LED 600 is bonded to the circuit substrate 100 by a solder layer 710. In this embodiment, the second LED 600 is a flip-chip LED having a first electrode 610 and a second electrode 650 located on the same side of the second LED 600. The first electrode 610 of the second LED 600 is connected to the first pad 102 via the solder layer 710, and the second electrode 650 is connected to the second pad 104 via the solder layer 710. In some embodiments, the melting point of the solder layer 710 is higher than 180 degrees Celsius, thus preventing the possibility of the solder layer 710 melting in subsequent processes.

[0027] As in Fig. 2B to Fig. As shown in Figure 2C, the multitude of anisotropic conductive adhesive structures 212 are arranged separately from one another over the circuit substrate 100. For example, the anisotropic conductive adhesive layer 210 is first applied to the entire surface of the carrier plate 200, as shown in Figure 2C. Fig. 1A is shown. Then, with reference to Fig. 2B, the carrier plate 200 and the anisotropic conductive adhesive layer 210 are arranged according to Fig. 2B is moved to the top of the circuit substrate 100, and the laser LS is used to irradiate a section of the anisotropic conductive adhesive layer 210. After irradiation with the laser LS, a section of the anisotropic conductive adhesive layer 210 is transferred to the circuit substrate 100 to form the anisotropic conductive adhesive structures 212, as shown in Fig. 2B to Fig. 2C shown.

[0028] In this embodiment, the anisotropic conductive adhesive structures 212 are formed on the first pads 102, which are not bonded to the second LED 600.

[0029] Referring to Fig. In 2D, a plurality of first light-emitting diodes 300 are arranged over the circuit substrate 100, wherein the anisotropic conductive adhesive structures 212 are located between the circuit substrate 100 and the first LEDs 300.

[0030] For example, the transfer substrate 400 is used to transfer the first LEDs 300 onto the circuit substrate 100, and the anisotropic conductive adhesive structures 212 are adhered to the first LEDs 300. The adhesive force between the first LEDs 300 and the anisotropic conductive adhesive structures 212 is greater than the adhesive force between the first LEDs 300 and the adhesive layer 410. Therefore, after the transfer substrate 400 has been removed, the first LEDs 300 can remain on the anisotropic conductive adhesive structures 212, with each anisotropic conductive adhesive structure 212 positioned between the circuit substrate 100 and the corresponding first LED 300.

[0031] In some embodiments, if the upper surface 100t of the circuit substrate 100 is taken as a reference, the height of the upper surface 300t of the first LED 300 is greater than the height of the upper surface 600t of the second LED 600. Therefore, the adhesive layer 410 will not touch the second LED 600 when the first LEDs 300 are transferred.

[0032] Then, in relation to Fig. 2E to Fig. In 2F, the first LEDs 300 are pressurized to enclose them in the anisotropic conductive adhesive structures 212. For example, the pressurizing element 500 is used to pressurize the plurality of first LEDs 300 simultaneously. In some embodiments, the surface of the pressurizing element 500 includes the buffer layer 510, and the buffer layer 510 contacts the plurality of first LEDs 300 simultaneously. In some embodiments, after the first LEDs 300 have been pressurized, the height of the upper surface 300t of the first LED 300 is greater than or equal to the height of the upper surface 600t of the second LED 600, with the upper surface 100t of the circuit substrate 100 serving as a reference. In other embodiments, the pressurizing element 500 and the buffer layer 510 can be kept away from the position where the second LED 600 is located.In this case, after the first LEDs 300 have been pressurized, the height of the upper surface 300t of the first LED 300 can be lower than the height of the upper surface 600t of the second LED 600.

[0033] Finally, regarding Fig. 2G is the multitude of conductive connecting elements 800 formed on the upper electrode 350 of the first LEDs 300, the anisotropic conductive adhesive structures 212, and the second pads 104 of the circuit substrate 100. A section of the conductive connecting element 800 is located on the anisotropic conductive adhesive structure 212. The conductive connecting element 800 electrically connects the upper electrode 350 of the first LED 300 to the second pad 104 of the circuit substrate 100.The conductive connecting element 800 is in contact with the upper electrode 350, the second semiconductor layer 340, and the second pad 104, and a section of the anisotropic conductive adhesive structure 212 is enclosed between the conductive connecting element 800 and the light-emitting layer 330, between the conductive connecting element 800 and the first semiconductor layer 320, between the conductive connecting element 800 and the lower electrode 310, and between the conductive connecting element 800 and the first pad 102. In some embodiments, the conductive connecting element 800 comprises metal, metal oxide (e.g., indium tin oxide), metal nitride, or other suitable materials.

[0034] In this embodiment, the anisotropic conductive adhesive structure 212 can be used as a step to prevent the conductive connecting element 800 from breaking due to an excessive step difference between the upper electrode 350 and the second pad 104, thereby reducing the manufacturing difficulties of the conductive connecting elements 800.

[0035] In this embodiment, a display device 20 comprises the circuit substrate 100, the first LEDs 300, the anisotropic conductive adhesive structures 212, the conductive connecting elements 800, the second LED 600, and the solder layer 710. In some embodiments, since the display device 20 contains the plurality of anisotropic conductive adhesive structures 212 that are separated from one another, a transparent area that does not contain the anisotropic conductive adhesive structures 212 can be incorporated into the display device 20 to make the display device 20 transparent. Compared to forming an anisotropic conductive film over the entire surface of the circuit substrate 100, the area of ​​the transparent region of the transparent display device can be increased by forming the plurality of anisotropic conductive adhesive structures 212 that are separated from one another.In some embodiments, the second LED 600 is a red LED, and the red LED with a flip-chip structure exhibits better red luminous efficacy than the red LED with a vertical structure. Therefore, the red LED in the display device 20 adopts a flip-chip structure to improve the red luminous efficacy of the display device 20.

[0036] Fig. Figure 3 is a schematic cross-sectional view of a manufacturing process for a display device according to an embodiment of the disclosure. It should be noted that the embodiment in Fig. 3 furthermore the reference numerals of the components and part of the content of the embodiment of Fig. 2A to Fig. 2G is used, where the same reference numerals denote the same or similar components and descriptions of the same technical content are omitted. For the descriptions of the omitted parts, reference may be made to the aforementioned embodiment, and its detailed descriptions are not repeated in the following embodiment.

[0037] Referring to Fig. Figure 3 describes the arrangement of the first LEDs 300 above the circuit substrate 100, and in this embodiment, a laser transfer. Specifically, the laser LS is used to irradiate the adhesive layer 410, causing the specific first LEDs 300 to leave the transfer substrate 400 and fall onto the anisotropic conductive adhesive structures 212. For the subsequent steps, reference can be made to the corresponding descriptions in [reference to relevant section]. Fig. 2E to Fig. 2G will be referred.

[0038] Fig. Figure 4 is a schematic cross-sectional view of a manufacturing process for a display device according to an embodiment of the disclosure. It should be noted that the embodiment in Fig. 4 furthermore the reference numerals of the components and part of the content of the embodiment of Fig. 1A to Fig. 1G is used, where the same reference numerals denote the same or similar components and descriptions of the same technical content are omitted. For the descriptions of the omitted parts, reference may be made to the aforementioned embodiment, and its detailed descriptions are not repeated in the following embodiment.

[0039] Referring to Fig. Section 4 describes the application of the anisotropic conductive adhesive structures 212 onto the circuit substrate 100 in the following steps. First, the plurality of separate anisotropic conductive adhesive structures 212 are formed on the carrier plate 200. Then, the anisotropic conductive adhesive structures 212 on the carrier plate 200 are separated from the carrier plate 200 by the laser LS and fall onto the first pads 102 of the circuit substrate 100. In this embodiment, the anisotropic conductive adhesive structures 212 are removed from the carrier plate 200 by the laser LS, but the disclosure is not limited to this. In other embodiments, the carrier plate 200 is pressed directly against the circuit substrate 100, and the plurality of anisotropic conductive adhesive structures 212 on the carrier plate 200 are adhered to the plurality of first pads 102 of the circuit substrate 100.

[0040] Fig. Figure 5 is a schematic cross-sectional view of an anisotropic conductive adhesive structure before pressurization according to an embodiment of the disclosure. Referring to Fig. 5 contains an anisotropic conductive adhesive structure 212a, a base material M, and a variety of conductive particles CP dispersed in the base material M. Before the anisotropic conductive adhesive structure 212a is pressurized (i.e., before the first LED is pressurized (referring to Fig. 1C and Fig. 2C)), the conductive particles CP are arranged in the base material M, and the conductive particles CP do not form a conductive path. After the anisotropic conductive adhesive structure 212a has been pressurized (i.e., after the first LED has been pressurized (referring to Fig. 1F and Fig. 2F)), the conductive particles CP can come into contact with each other in a pressurized direction to form a conductive path in the pressurized direction.

[0041] Fig. Figure 6 is a schematic cross-sectional view of an anisotropic conductive adhesive structure before pressurization according to an embodiment of the disclosure. Referring to Fig. 6 comprises an anisotropic conductive adhesive structure 212b, a base material M, and a plurality of conductive particles CP dispersed in the base material M. In this embodiment, the conductive particle CP comprises a conductive core CC and an insulating layer I, the insulating layer I being located on a surface of the conductive core CC. The insulating layer I can be used to prevent the anisotropic conductive adhesive structure 212b from generating an unexpected conductive path. Before the anisotropic conductive adhesive structure 212b is pressurized (i.e., before the first LED is pressurized (referring to Fig. 1C and Fig. 2C)), the insulating layer I envelops the conductive core CC, so that even if the conductive particles CP are in contact with each other, the conductive cores CC do not readily connect with each other to form a conductive path. After the anisotropic conductive adhesive structure 212b has been pressurized (i.e., after the first LED has been pressurized (referring to Fig. 1F and Fig. 2F)), the conductive particles CP can come into contact with each other in the pressurized direction, and the insulating layers I are broken under pressure to form the conductive cores CC which are connected to each other to form a conductive path in the pressurized direction.

[0042] In summary, the first LEDs of the disclosure are electrically connected to the circuit substrate by the anisotropic conductive adhesive structures, thereby reducing the probability of LED dropout. Furthermore, by forming the conductive connectors on the anisotropic conductive adhesive structures, the risk of breakage of the conductive connectors due to excessive step differences can be reduced, thus mitigating the difficulties in fabricating the conductive connectors.

Claims

[1] Display device (10, 20) comprising: a circuit substrate (100); a first light-emitting diode (300) located above the circuit substrate (100); an anisotropic conductive adhesive structure (212, 212a, 212b) located between the circuit substrate (100) and the first light-emitting diode (300) and electrically connecting the circuit substrate (100) to a lower electrode (310) of the first light-emitting diode (300), wherein, taking a top surface (100t) of the circuit substrate (100) as a reference, a height of a top surface (212t) of the anisotropic conductive adhesive structure (212, 212a, 212b) is greater than or equal to a height of a top surface (330t) of a light-emitting layer (330) of the first light-emitting diode (300), and the height of the top surface (212t) of the anisotropic conductive adhesive structure (212, 212a, 212b) is less than a height of a top surface (330t) of the first light-emitting diode (300). electrode (350) of the first light-emitting diode (300) is; and a conductive connecting element (800) that electrically connects the upper electrode (350) of the first light-emitting diode (300) to the circuit substrate (100), wherein part of the conductive connecting element (800) is located on the anisotropic conductive adhesive structure (212, 212a, 212b). [2] Display device (10, 20) according to claim 1, wherein the anisotropic conductive adhesive structure (212, 212a, 212b) comprises a carbon black material. [3] Display device (10, 20) according to claim 1 or 2, wherein the anisotropic conductive adhesive structure (212, 212a, 212b) comprises: a base material (M); and a multitude of conductive particles (CP) dispersed in the base material (M), each of the conductive particles (CP) comprising: a conductive core (CC) and an insulating layer (I) located on a surface of the conductive core (CC). [4] Display device (10, 20) according to any one of claims 1 to 3, further comprising: a second light-emitting diode (600) located above the circuit substrate (100) and electrically connected to the circuit substrate (100) by a solder layer (710), wherein the melting point of the solder layer (710) is higher than 180 degrees Celsius. [5] Display device (10, 20) according to claim 4, wherein the first light-emitting diode (300) is a vertical light-emitting diode and the second light-emitting diode (600) is a flip-chip light-emitting diode. [6] Display device (10, 20) according to claim 4, wherein, taking the upper surface (100t) of the circuit substrate (100) as a reference, a height of an upper surface (300t) of the first light-emitting diode (300) is lower than or equal to a height of an upper surface (600t) of the second light-emitting diode (600). [7] Display device (10, 20) according to any one of claims 1 to 6, further comprising: a large number of first light-emitting diodes (300) located above the circuit substrate (100), a plurality of anisotropic conductive adhesive structures (212, 212a, 212b) located between the circuit substrate (100) and the first light-emitting diodes (300), each of the anisotropic conductive adhesive structures (212, 212a, 212b) electrically connecting the circuit substrate (100) to the corresponding first light-emitting diode (300), the anisotropic conductive adhesive structures (212, 212a, 212b) being separated from each other; and a plurality of conductive connecting elements (800), wherein each of the conductive connecting elements (800) electrically connects the corresponding first light-emitting diode (300) to the circuit substrate (100). [8] Display device (10, 20) according to any one of claims 1 to 7, wherein the first light-emitting diode (300) comprises the lower electrode (310), a first semiconductor layer (320), the light-emitting layer (330), a second semiconductor layer (340) and the upper electrode (350) stacked one after the other, wherein the anisotropic conductive adhesive structure (212, 212a, 212b) covers a side wall of the first semiconductor layer (320). [9] Display device (10, 20) according to claim 8, wherein the conductive connecting element (800) contacts the upper electrode (350) and the second semiconductor layer (340). [10] Method for manufacturing a display device, comprising: Applying an anisotropic conductive adhesive structure (212, 212a, 212b) over a circuit substrate (100); Arranging a first light-emitting diode (300) over the circuit substrate (100), wherein the anisotropic conductive adhesive structure (212, 212a, 212b) is located between the circuit substrate (100) and the first light-emitting diode (300); Pressurizing the first light-emitting diode (300) such that the first light-emitting diode (300) is enclosed in the anisotropic conductive adhesive structure (212, 212a, 212b), wherein, taking a top surface (100t) of the circuit substrate (100) as a reference, a height of a top surface (212t) of the anisotropic conductive adhesive structure (212, 212a, 212b) is greater than or equal to a height of a top surface (330t) of a light-emitting layer (330) of the first light-emitting diode (300), and the height of the top surface of the anisotropic conductive adhesive structure (212, 212a, 212b) is less than a height of a top electrode (350) of the first light-emitting diode (300), wherein the anisotropic conductive adhesive structure (212, 212a, 212b) electrically connects the circuit substrate (100) to a lower electrode (310) of the first light-emitting diode (300); and Forming a conductive connecting element (800) on the upper electrode (350) of the first light-emitting diode (300), the anisotropic conductive adhesive structure (212, 212a, 212b) and the circuit substrate (100), wherein the conductive connecting element (800) electrically connects the upper electrode (350) of the first light-emitting diode (300) to the circuit substrate (100). [11] Manufacturing method according to claim 10, wherein, before the first light-emitting diode (300) is pressurized, a thickness (T1) of the anisotropic conductive adhesive structure (212, 212a, 212b) is greater than a thickness (T2) of the lower electrode (310) of the first light-emitting diode (300) and a width (W1) of the anisotropic conductive adhesive structure (212, 212a, 212b) is greater than a width (W2) of the first light-emitting diode (300). [12] Manufacturing method according to claim 10 or 11, wherein the anisotropic conductive adhesive structure (212, 212a, 212b) comprises: a base material (M); and a large number of conductive particles (CP) dispersed in the base material (M), wherein the conductive particles (CP) are lined up in the base material (M) before the first light-emitting diode (300) is pressurized. [13] Manufacturing method according to any one of claims 10 to 12, comprising applying the anisotropic conductive adhesive structure (212, 212a, 212b) over the circuit substrate (100): Bonding an anisotropic, conductive adhesive layer (210) to an entire surface of a carrier plate; Moving the carrier plate and the anisotropic conductive adhesive layer (210) onto the top side of the circuit substrate (100); and Irradiating part of the anisotropic conductive adhesive layer (210) with a laser to transfer part of the anisotropic conductive adhesive layer (210) onto the circuit substrate (100) to form the anisotropic conductive adhesive structure (212, 212a, 212b). [14] Manufacturing method according to any one of claims 10 to 13, wherein the manufacturing method further comprises, prior to applying the anisotropic conductive adhesive structure (212, 212a, 212b) over the circuit substrate (100): Bonding a second light-emitting diode (600) to the circuit substrate (100) by means of a solder layer (710), wherein a melting point of the solder layer (710) is higher than 180 degrees Celsius. [15] Manufacturing method according to claim 14, wherein the first light-emitting diode (300) is a vertical light-emitting diode and the second light-emitting diode (600) is a flip-chip light-emitting diode. [16] Manufacturing process according to any one of claims 10 to 15, further comprising: Applying a plurality of anisotropic conductive adhesive structures (212, 212a, 212b) over the circuit substrate (100); Arranging a plurality of first light-emitting diodes (300) over the circuit substrate (100), wherein each of the anisotropic conductive adhesive structures (212, 212a, 212b) is located between the circuit substrate (100) and the corresponding first light-emitting diode (300); Applying pressure to the first light-emitting diodes (300) so that the first light-emitting diodes (300) are enclosed in the anisotropic conductive adhesive structures (212, 212a, 212b); and Forming a plurality of conductive connecting elements (800) on the first light-emitting diodes (300), the anisotropic conductive adhesive structures (212, 212a, 212b) and the circuit substrate (100), wherein each of the conductive connecting elements (800) electrically connects the corresponding first light-emitting diode (300) to the circuit substrate (100). [17] Manufacturing method according to claim 16, comprising the pressurizing of the first light-emitting diodes (300): Simultaneous pressurization of the first light-emitting diodes (300) by a pressurization element (500).

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