Light emitting element for display and LED display device having the same

Abstract

A light-emitting element according to one embodiment includes: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; and a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack, wherein the second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack, and one of the first adhesive layer and the second adhesive layer is a conductive adhesive layer electrically connected to an adjacent light-emitting stack.

Description

Technical Field

[0001] This disclosure relates to a light-emitting element for display and an LED display device having the same. Background Technology

[0002] Light-emitting diodes (LEDs), as inorganic light sources, are widely used in various fields such as display devices, vehicle lighting, and general lighting. LEDs have advantages such as long lifespan, low power consumption, and fast response speed, and are therefore rapidly replacing existing light sources.

[0003] In addition, existing light-emitting diodes (LEDs) are mainly used as backlights in display devices. However, LED displays that utilize LEDs to directly display images are currently under development.

[0004] Display devices typically utilize a mixture of blue, green, and red to achieve a variety of colors. To realize diverse images, a display device includes multiple pixels, each pixel having blue, green, and red sub-pixels. The color of a specific pixel is determined by the colors of these sub-pixels, and the image is realized through the combination of these pixels.

[0005] LEDs can emit a variety of colors of light depending on their material, thus providing a display device by arranging individual LED chips that emit blue, green, and red light on a two-dimensional plane. However, when an LED chip is arranged in each sub-pixel, the number of LED chips increases, resulting in a significant increase in the time required for the mounting process.

[0006] Because subpixels are arranged on a two-dimensional plane, the area occupied by a single pixel, including blue, green, and red subpixels, is relatively wider. Therefore, in order to arrange subpixels within a limited area, the area of ​​each LED chip needs to be reduced. However, reducing the size of the LED chip makes its mounting more difficult, leading to a reduction in the light-emitting area. Summary of the Invention

[0007] The technical problem this disclosure aims to solve is to provide a display device that can increase the area of ​​each sub-pixel within a limited pixel area.

[0008] Another technical problem that this disclosure aims to solve is to provide a display device that can shorten the mounting process time.

[0009] A light-emitting element according to an embodiment of the present disclosure includes: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; and a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack, wherein the second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack, and one of the first adhesive layer and the second adhesive layer is a conductive adhesive layer electrically connected to an adjacent light-emitting stack.

[0010] According to another embodiment of the present disclosure, a light-emitting stack includes: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack; a first insulating layer covering the first light-emitting stack to the third light-emitting stack; and a first pad, a second pad, a third pad, and a fourth pad disposed on the first insulating layer, wherein the second light-emitting stack and the third light-emitting stack are bonded by the second adhesive layer such that the first conductive semiconductor layers of the second light-emitting stack and the third light-emitting stack are adjacent to each other, the first insulating layer includes a contact hole that exposes the first conductive semiconductor layers of the second light-emitting stack and the third light-emitting stack together, and the fourth pad is electrically connected to the first conductive semiconductor layers of the second light-emitting stack and the third light-emitting stack through the contact hole.

[0011] A display device according to an embodiment of the present disclosure includes: a display substrate; a plurality of light-emitting elements disposed on the display substrate; and a molding layer covering the sides of the light-emitting elements, wherein the light-emitting elements include: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack, wherein the second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack, and one of the first adhesive layer and the second adhesive layer is a conductive adhesive layer electrically connected to an adjacent light-emitting stack.

[0012] A display device according to another embodiment of the present disclosure includes: a display substrate; a plurality of light-emitting elements disposed on the display substrate; and a molding layer covering the sides of the light-emitting elements, wherein the light-emitting elements include: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack; and a first insulating layer covering the sides of the light-emitting elements. The first light-emitting stack to the third light-emitting stack, and the first pad to the fourth pad, are disposed on the first insulating layer, and the second light-emitting stack and the third light-emitting stack are bonded by the second adhesive layer such that the first conductive semiconductor layer of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack are adjacent to each other. The first insulating layer includes contact holes that expose the first conductive semiconductor layers of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack together. The fourth pad is electrically connected to the first conductive semiconductor layer of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack through the contact holes. Attached Figure Description

[0013] Figure 1a This is a schematic perspective view illustrating a light-emitting element according to an embodiment of the present disclosure.

[0014] Figure 1b yes Figure 1a A schematic plan view of the light-emitting element.

[0015] Figure 1c and Figure 1d They are respectively along Figure 1b A schematic cross-sectional view obtained by cutting lines AA′ and BB′.

[0016] Figure 2 This is a schematic cross-sectional view of a light-emitting stacked structure according to an embodiment of the present disclosure.

[0017] Figure 3a , Figure 4a , Figure 5a , Figure 6a , Figure 7a and Figure 8a This illustrates the manufacture according to an exemplary embodiment. Figure 1a A plan view of the process of the light-emitting element.

[0018] Figure 3b , Figure 4b , Figure 5b , Figure 6b , Figure 7b and Figure 8b It is along according to the exemplary embodiment. Figure 3a , 4a The cross-sectional view of the AA′ line of the corresponding plan view shown in 5a, 6a, 7a and 8a.

[0019] Figure 3c , Figure 4c , Figure 5c , Figure 6c , Figure 7c and Figure 8c It is along according to the exemplary embodiment. Figure 3a , 4a The BB′ line cross-section of the corresponding plan view shown in 5a, 6a, 7a and 8a.

[0020] Figure 9a and Figure 9b These are schematic cross-sectional and plan views used to illustrate a light-emitting package according to an exemplary embodiment.

[0021] Figure 10 This is a schematic cross-sectional view used to illustrate a display device according to an embodiment of the present disclosure.

[0022] Figure 11 This is a schematic cross-sectional view used to illustrate a light-emitting package according to an embodiment of the present disclosure.

[0023] Figure 12 This is a schematic cross-sectional view of a light-emitting stacked structure according to an embodiment of the present disclosure.

[0024] Figure 13 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0025] Figure 14 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0026] Figure 15 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0027] Figure 16 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0028] Figure 17 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0029] Figure 18 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0030] Figure 19 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0031] Figure 20a This is a schematic plan view illustrating a light-emitting element of yet another embodiment of the present disclosure.

[0032] Figure 20b It is along Figure 20a A schematic cross-sectional view obtained by cutting line AA′.

[0033] Figure 20c It is along Figure 20a A schematic cross-sectional view is obtained by cutting the cutting line BB′. Detailed Implementation

[0034] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. To fully convey the ideas of the present disclosure to those skilled in the art, the following embodiments are provided as examples. Therefore, the present disclosure is not limited to the embodiments described below, and may be embodied in other forms. Furthermore, in the drawings, the width, length, thickness, etc., of the constituent elements may be exaggerated for convenience. Also, when described as one constituent element being "above" or "on top of" another constituent element, this includes not only cases where each part is "directly" located "above" or "on top" other parts, but also cases where another constituent element is sandwiched between each constituent element and another constituent element. Throughout the specification, the same reference numerals denote the same constituent elements.

[0035] A light-emitting element according to an embodiment of the present disclosure includes: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack, wherein the second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack, and one of the first adhesive layer and the second adhesive layer is a conductive adhesive layer electrically connected to an adjacent light-emitting stack.

[0036] Because the first to third light-emitting stacks overlap each other, the area of ​​each sub-pixel can be increased within a limited pixel area without increasing the pixel area. Furthermore, since the light-emitting element includes the first to third light-emitting stacks, the number of light-emitting elements can be reduced compared to existing light-emitting elements, thus shortening the light-emitting element mounting process time. In particular, since one of the first and second adhesive layers is a conductive adhesive layer that electrically connects to its adjacent light-emitting stacks, the light-emitting element manufacturing process can be simplified.

[0037] In one embodiment, the conductive adhesive layer may comprise indium tin oxide (ITO). For example, the conductive adhesive layer may be formed using ITO bonding technology.

[0038] In one embodiment, the first, second, and third light-emitting stacks can emit red, green, and blue light, respectively. In another embodiment, the first, second, and third light-emitting stacks can emit red, blue, and green light, respectively. By having the second light-emitting stack emit blue light and the third light-emitting stack emit green light, the intensity of the blue light is reduced and the intensity of the green light is increased, thereby adjusting the RGB mixing ratio.

[0039] In addition, the light-emitting element may also include: a first connecting electrode electrically connected to the first light-emitting stack; a second connecting electrode electrically connected to the second light-emitting stack; a third connecting electrode electrically connected to the third light-emitting stack; and a fourth connecting electrode, which are collectively electrically connected to the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack.

[0040] Furthermore, the fourth connecting electrode is electrically connected to the light-emitting stack adjacent to the conductive adhesive layer through the conductive adhesive layer.

[0041] In one embodiment, the fourth connecting electrode can be electrically connected to the first conductive semiconductor layer of the first light-emitting stack to the third light-emitting stack, and the first conductive semiconductor layer can be an n-type semiconductor layer.

[0042] In another embodiment, the fourth connection electrode may be electrically connected together to the second conductive semiconductor layer of the first light-emitting stack to the third light-emitting stack, and the second conductive semiconductor layer may be a p-type semiconductor layer.

[0043] Additionally, the light-emitting element may further include a protective layer surrounding at least a portion of the first to fourth connecting electrodes. The protective layer may comprise an epoxy molding compound or a polyimide film, and its upper surface may be parallel to the upper surfaces of the first to fourth connecting electrodes.

[0044] In some embodiments, the light-emitting element may further include a substrate arranged adjacent to the third light-emitting stack.

[0045] A light-emitting element according to another embodiment of the present disclosure includes: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack; a first insulating layer covering the first light-emitting stack to the third light-emitting stack; and a first pad to a fourth pad disposed on the first insulating layer, wherein the second light-emitting stack and the third light-emitting stack are bonded by the second adhesive layer such that the first conductive semiconductor layer of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack are adjacent to each other, the first insulating layer includes a contact hole that exposes the first conductive semiconductor layer of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack together, and the fourth pad is electrically connected to the first conductive semiconductor layer of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack through the contact hole.

[0046] The first pad can be electrically connected to the second conductive semiconductor layer of the first light-emitting stack through the first insulating layer. The second pad can be electrically connected to the second conductive semiconductor layer of the second light-emitting stack through the first insulating layer. The third pad can be electrically connected to the second conductive semiconductor layer of the third light-emitting stack through the first insulating layer. The fourth pad can be additionally electrically connected to the first conductive semiconductor layer of the first light-emitting stack through the first insulating layer.

[0047] Additionally, the light-emitting element may further include: a second insulating layer covering the first to fourth pads and having through holes exposing the first to fourth pads; and a first to fourth connecting electrode disposed on the second insulating layer and electrically connected to the first to fourth pads respectively through the through holes of the second insulating layer.

[0048] Furthermore, the light-emitting element may also include a protective layer surrounding at least a portion of the connecting electrode.

[0049] A display device according to an embodiment of the present disclosure includes: a display substrate; a plurality of light-emitting elements disposed on the display substrate; and a molding layer covering the sides of the plurality of light-emitting elements, wherein the light-emitting elements include: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; and a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack, wherein the second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack, and one of the first adhesive layer and the second adhesive layer is a conductive adhesive layer electrically connected to an adjacent light-emitting stack.

[0050] In one embodiment, the conductive adhesive layer may include ITO.

[0051] Additionally, the light-emitting element may further include: a first connecting electrode electrically connected to the first light-emitting stack; a second connecting electrode electrically connected to the second light-emitting stack; a third connecting electrode electrically connected to the third light-emitting stack; and a fourth connecting electrode, which is collectively electrically connected to the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack. The fourth connecting electrode is electrically connected to the light-emitting stack adjacent to the conductive adhesive layer through the conductive adhesive layer.

[0052] Furthermore, the fourth connecting electrode can be electrically connected to the first conductive semiconductor layer of the first light-emitting stack to the third light-emitting stack, and the first conductive semiconductor layer can be an n-type semiconductor layer.

[0053] A display device according to another embodiment of the present disclosure includes: a display substrate; a plurality of light-emitting elements disposed on the display substrate; and a molding layer covering the sides of the plurality of light-emitting elements, wherein the light-emitting elements include: a first light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a second light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a third light-emitting stack comprising a first conductive semiconductor layer and a second conductive semiconductor layer; a first adhesive layer bonding the first light-emitting stack and the second light-emitting stack; a second adhesive layer bonding the second light-emitting stack and the third light-emitting stack; and a first insulating layer. The first light-emitting stack to the third light-emitting stack are covered by a second adhesive layer, and a first pad to a fourth pad are disposed on the first insulating layer, wherein the second light-emitting stack and the third light-emitting stack are bonded by the second adhesive layer such that the first conductive semiconductor layer of the second light-emitting stack and the first conductive semiconductor layer of the third light-emitting stack are adjacent to each other, the first insulating layer includes contact holes that expose the first conductive semiconductor layers of the second light-emitting stack and the first conductive semiconductor layers of the third light-emitting stack together, and the fourth pad is electrically connected to the first conductive semiconductor layers of the second light-emitting stack and the third light-emitting stack through the contact holes.

[0054] The light-emitting element may further include: a second insulating layer covering the first to fourth pads and having through holes exposing the first to fourth pads; and a first to fourth connecting electrode disposed on the second insulating layer and electrically connected to the first to fourth pads respectively through the through holes of the second insulating layer.

[0055] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. In the following description, the light-emitting stack structure, light-emitting element, and light-emitting package may include a micro LED, as is known in the art, with a light-emitting area of ​​10000 μm. 2 Below. As another embodiment, the microLED can have a size of 4000 μm. 2 The following luminescent area, thus having 2500μm 2 The following is the luminous area.

[0056] Figure 1a This is a schematic perspective view illustrating a light-emitting element according to an embodiment of the present disclosure. Figure 1b yes Figure 1a A schematic plan view of the light-emitting element. Figure 1c and Figure 1d They are respectively along Figure 1b A schematic cross-sectional view obtained by cutting lines AA′ and BB′.

[0057] Reference Figure 1a as well as Figure 1b The light-emitting element 100 includes: a light-emitting stacked structure; a first connecting electrode 20ce, a second connecting electrode 30ce, a third connecting electrode 40ce, and a fourth connecting electrode 50ce, formed on the light-emitting stacked structure; and a protective layer 90 surrounding the connecting electrodes 20ce, 30ce, 40ce, and 50ce. An array of light-emitting elements 100 can be formed on a substrate 11, and... Figure 1a The light-emitting element 100 shown in the illustration represents a light-emitting element unified from the array. The formation and unification of the light-emitting element 100 will be described in detail later. In some embodiments, the light-emitting element 100, including a light-emitting stack structure, may be further processed to form a light-emitting package, which will also be described in detail later.

[0058] Reference Figures 1a to 1d The light-emitting element 100 according to the illustrated embodiment includes a light-emitting stack structure, which may include a first LED sub-unit, a second LED sub-unit, and a third LED sub-unit. The first LED sub-unit may include a first light-emitting stack 20, the second LED sub-unit may include a second light-emitting stack 30, and the third LED sub-unit may include a third light-emitting stack 40. The light-emitting stack structure shown includes three light-emitting stacks 20, 30, and 40, but this disclosure is not limited to a specific number of light-emitting stacks. For example, in some embodiments, the light-emitting stack structure may include two or more light-emitting stacks. A light-emitting stack structure including three light-emitting stacks 20, 30, and 40 according to one embodiment will be described herein.

[0059] The substrate 11 is an element used to support the light-emitting stacks 20, 30, and 40, and may be included in the light-emitting element 100, but may also be removed from the light-emitting stacks 20, 30, and 40. When the substrate 11 is included in the light-emitting element 100, the substrate 11 may include a light-transmitting insulating material. For example, the substrate 11 may include sapphire, glass, quartz, silicon, organic polymers, or organic-inorganic composite materials, such as silicon carbide (SiC), gallium nitride (GaN), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN), aluminum nitride (AlN), gallium oxide (Ga2O3), or a silicon substrate.

[0060] The first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 are configured to emit light toward the substrate 11 or the third lower contact electrode 45p. Therefore, light emitted from the first light-emitting stack 20 can pass through the second light-emitting stack 30 and the third light-emitting stack 40. According to one embodiment, the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 can emit light with different peak wavelengths. In one embodiment, the light-emitting stack farther from the third lower contact electrode 45p can emit light with a longer wavelength than the light-emitting stack closer to the third lower contact electrode 45p, thereby reducing light loss. For example, the first light-emitting stack 20 can emit red light, the second light-emitting stack 30 can emit green light, and the third light-emitting stack 40 can emit blue light.

[0061] In another embodiment, to adjust the color mixing ratio of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40, the second light-emitting stack 30 can emit light with a wavelength shorter than that of the third light-emitting stack 40. Accordingly, the luminous intensity of the second light-emitting stack 30 can be reduced, and the luminous intensity of the third light-emitting stack 40 can be increased. Therefore, the ratio of the luminous intensities of the light emitted from the first, second, and third light-emitting stacks can be drastically changed. For example, the first light-emitting stack 20 can be configured to emit red light, the second light-emitting stack 30 can be configured to emit blue light, and the third light-emitting stack 40 can be configured to emit green light. Accordingly, the luminous intensity of blue light can be relatively reduced, and the luminous intensity of green light can be relatively increased. Therefore, the ratio of the luminous intensities of red, green, and blue can be easily adjusted to approximately 3:6:1. Furthermore, the luminous area of ​​the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 can be approximately 10000 μm. 2 The following is further reduced to 4000μm. 2 Below, it is further increased to 2500μm 2 Furthermore, the closer to the third lower contact electrode 45p, the larger the light-emitting area can be, and the third light-emitting stack 40 emitting green light is arranged to be closest to the third lower contact electrode 45p, thereby further increasing the light-emitting intensity of the green light.

[0062] The first light-emitting stack 20 includes a first conductive semiconductor layer 21, an active layer 23, and a second conductive semiconductor layer 25. According to one embodiment, the first light-emitting stack 20 may include, for example, a red-light-emitting semiconductor material such as AlGaAs, GaAsP, AlGaInP, and GaP, but is not limited thereto.

[0063] The first upper contact electrode 21n is disposed on the first conductive semiconductor layer 21 and can form an ohmic contact with the first conductive semiconductor layer 21. The first lower contact electrode 25p can be disposed below the second conductive semiconductor layer 25. According to one embodiment, a portion of the first conductive semiconductor layer 21 can be patterned and recessed, and the first upper contact electrode 21n is disposed in the recessed region of the first conductive semiconductor layer 21 to increase the degree of ohmic contact. The first upper contact electrode 21n can have a single-layer structure or a multi-layer structure, and can include Al, Ti, Cr, Ni, Au, Ag, Sn, W, Cu or alloys thereof, such as Au-Te alloy or Au-Ge alloy, but is not limited thereto. In one embodiment, the first upper contact electrode 21n can have a thickness of about 100 nm, and can include a metal with high reflectivity to increase luminous efficiency downward toward the third lower contact electrode 45p.

[0064] The second light-emitting stack 30 includes a first conductive semiconductor layer 31, an active layer 33, and a second conductive semiconductor layer 35. According to one embodiment, the second light-emitting stack 30 may include a blue-light-emitting semiconductor material such as GaN, InGaN, or ZnSe, but is not limited thereto. A second lower contact electrode 35p is disposed on the second conductive semiconductor layer 35 of the second light-emitting stack 30.

[0065] The third light-emitting stack 40 includes a first conductive semiconductor layer 41, an active layer 43, and a second conductive semiconductor layer 45. According to one embodiment, the third light-emitting stack 40 may include a green-light-emitting semiconductor material such as GaN, InGaN, GaP, AlGaInP, or AlGaP. A third lower contact electrode 45p is disposed below the second conductive semiconductor layer 45 of the third light-emitting stack 40. As described above, the semiconductor materials of the second light-emitting stack 30 and the third light-emitting stack 40 can be interchanged.

[0066] According to one embodiment, each of the first conductive semiconductor layers 21, 31, 41 and the second conductive semiconductor layers 25, 35, 45 of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 has a single-layer structure or a multi-layer structure. In some embodiments, a superlattice layer may be included. In particular, the active layers 23, 33, 43 of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 may have a single quantum well structure or a multi-quantum well structure.

[0067] Each of the first lower contact electrode 25p, the second lower contact electrode 35p, and the third lower contact electrode 45p may include a transparent conductive material that transmits light. For example, the lower contact electrodes 25p, 35p, and 45p may include a transparent conductive oxide (TCO), such as SnO, InO2, ZnO, ITO (indium tin oxide), ITZO (indium tin zinc oxide), etc., but are not limited to these.

[0068] The first adhesive layer 61 is disposed between the first light-emitting stack 20 and the second light-emitting stack 30, the second adhesive layer 63 is disposed between the second light-emitting stack 30 and the third light-emitting stack 40, and the third adhesive layer 65 is disposed between the substrate 11 and the third light-emitting stack 40.

[0069] The first adhesive layer 61 may include a non-conductive material that transmits light. For example, the first adhesive layer 61 may include an optically transparent adhesive (OCA), which may include, but is not limited to, epoxy resin, polyimide, SU8, spin-coated glass (SOG), benzocyclobutene (BCB).

[0070] In this embodiment, the second adhesive layer 63 comprises a conductive material. The second adhesive layer 63 can be electrically connected to the first conductive semiconductor layer 31 of the second light-emitting stack 30 and the first conductive semiconductor layer 41 of the third light-emitting stack 40. For example, the second adhesive layer 63 can be an adhesive layer of conductive oxide layers 31n and 41n such as ITO. By forming the second adhesive layer 63 as a conductive material layer, the first conductive semiconductor layer 31 and the first conductive semiconductor layer 41 can be electrically connected, thus simplifying the manufacturing process of the light-emitting element 100.

[0071] The third adhesive layer 65 can bond the substrate 11 and the third light-emitting stack 40, and can be removed together with the substrate 11 when the substrate 11 is removed. In this case, for example, the third adhesive layer 65 can be formed of an adhesive material that reacts to laser, so the substrate 11 can be easily removed from the light-emitting stacks 20, 30, 40 using a laser.

[0072] Additionally, according to the illustrated embodiment, the first insulating layer 81 and the second insulating layer 83 are disposed on at least a portion of the sides of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40. At least one of the first insulating layer 81 and the second insulating layer 83 may comprise a variety of organic or inorganic insulating materials (e.g., polyimide, SiO2, SiN). x(e.g., Al2O3, etc.). For example, at least one of the first insulating layer 81 and the second insulating layer 83 may include a distributed Bragg reflector (DBR). As another embodiment, at least one of the first insulating layer 81 and the second insulating layer 83 may include a black organic polymer. In some embodiments, an electrically floating metal reflective layer is disposed on the first insulating layer 81 and the second insulating layer 83 to reflect light emitted from the light-emitting stacks 20, 30, and 40 toward the third lower contact electrode 45p side. In some embodiments, at least one of the first insulating layer 81 and the second insulating layer 83 may have a single-layer structure or a multilayer structure formed using two or more insulating layers with different refractive indices.

[0073] The first conductive semiconductor layers 21, 31, and 41 of each light-emitting stack can be n-type semiconductor layers, and the second conductive semiconductor layers 25, 35, and 45 can be p-type semiconductor layers. The first lower contact electrode 25p, the second lower contact electrode 35p, and the third lower contact electrode 45p, respectively connected to the p-type semiconductor layers 25, 35, and 45 of the light-emitting stack, can be electrically connected to the first connecting electrode 20ce, the second connecting electrode 30ce, and the third connecting electrode 40ce, respectively. Furthermore, the n-type semiconductor layers 21, 31, and 41 of the light-emitting stack are commonly connected to the fourth connecting electrode 50ce. Accordingly, the light-emitting element 100 can have a common n-type light-emitting stack structure in which the n-type semiconductor layers 21, 31, and 41 of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 are commonly connected, and can be driven independently. Because it has a common n-type light-emitting stack structure, the voltage sources applied to the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 can be different from each other.

[0074] Although the light-emitting element 100 according to the illustrated embodiment has a common n-type structure, this disclosure is not limited thereto. For example, in some exemplary embodiments, the first conductive semiconductor layers 21, 31, and 41 of each light-emitting stack can be p-type semiconductor layers, and the second conductive semiconductor layers 25, 35, and 45 of each light-emitting stack can be n-type semiconductor layers, thus forming a common p-type light-emitting stack structure. Furthermore, in some embodiments, the stacking order of the various light-emitting stacks is not limited to that shown in the drawings, but can be varied in many ways. Hereinafter, a light-emitting element 100 according to an embodiment of this disclosure will be described with reference to a common n-type light-emitting stack structure.

[0075] According to the illustrated embodiment, the light-emitting element 100 includes a first pad 20pd, a second pad 30pd, a third pad 40pd, and a fourth pad 50pd. The first pad 20pd is electrically connected to a first lower contact electrode 25p through a first contact hole 20CH defined by a first insulating layer 81. A first connecting electrode 20ce is electrically connected to the first pad 20pd through a first through hole 20ct defined by a second insulating layer 83. The second pad 30pd is electrically connected to a second lower contact electrode 35p through a second contact hole 30CH defined by the first insulating layer 81. The second connecting electrode 30ce is electrically connected to the second pad 30pd through a second through hole 30ct defined by the second insulating layer 83.

[0076] The third pad 40pd is electrically connected to the third lower contact electrode 45p through a third contact hole 40CH defined by the first insulating layer 81. The third connecting electrode 40ce is electrically connected to the third pad 40pd through a third through hole 40ct defined by the second insulating layer 83.

[0077] The fourth pad 50pd is electrically connected to the first conductive semiconductor layers 21, 31, and 41 of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 through the first sub-contact hole 50CHa and the second sub-contact hole 50CHb. The first sub-contact hole 50CHa can expose the first upper contact electrode 21n, and the fourth pad 50pd can be connected to the first upper contact electrode 21n through the first sub-contact hole 50CHa. Furthermore, the second sub-contact hole 50CHb can be formed on the second adhesive layer 63 to expose a portion of the second adhesive layer 63, and the fourth pad 50pd can be electrically connected to the second adhesive layer 63 through the second sub-contact hole 50CHb. By forming the second adhesive layer 63 as a conductive layer, the fourth pad 50pd can be electrically connected to both the first conductive semiconductor layer 31 and the first conductive semiconductor layer 41 through the second sub-contact hole 50CHb.

[0078] The fourth connecting electrode 50ce is electrically connected to the fourth pad 50pd through the fourth through hole 50ct defined by the second insulating layer 83. Therefore, the fourth connecting electrode 50ce is electrically connected to the first conductive semiconductor layers 21, 31, and 41 through the fourth pad 50pd.

[0079] In this embodiment, although the diagram and description show the connecting electrodes 20ce, 30ce, 40ce, and 50ce directly contacting the pads 20pd, 30pd, 40pd, and 50pd, respectively, other connectors may be placed between the connecting electrodes 20ce, 30ce, 40ce, and 50ce and the pads 20pd, 30pd, 40pd, and 50pd, without directly connecting the connecting electrodes 20ce, 30ce, 40ce, and 50ce to the pads 20pd, 30pd, 40pd, and 50pd.

[0080] The first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd are spaced apart from and insulated from each other. According to one embodiment, the first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd may respectively cover at least a portion of the side surfaces of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40. Accordingly, heat generated from the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 can be easily dissipated.

[0081] According to the illustrated embodiment, each of the connecting electrodes 20ce, 30ce, 40ce, and 50ce may have a substantially elongated shape protruding from the substrate 11. The connecting electrodes 20ce, 30ce, 40ce, and 50ce may comprise, but are not limited to, metals such as Cu, Ni, Ti, Sb, Zn, Mo, Co, Sn, Ag, or alloys thereof. For example, each of the connecting electrodes 20ce, 30ce, 40ce, and 50ce may comprise two or more metals or multiple different metal layers to reduce stress from the elongated shape of the connecting electrodes 20ce, 30ce, 40ce, and 50ce. In another embodiment, when the connecting electrodes 20ce, 30ce, 40ce, and 50ce comprise Cu, additional metal may be deposited or plated to suppress Cu oxidation. In some embodiments, when the connecting electrodes 20ce, 30ce, 40ce, and 50ce comprise Cu / Ni / Sn, Cu may prevent Sn from penetrating into the light-emitting stack structure. In some embodiments, the connecting electrodes 20ce, 30ce, 40ce, and 50ce may include a seed layer for forming a metal layer during the plating process, as will be described later.

[0082] As shown in the figure, each connecting electrode 20ce, 30ce, 40ce, and 50ce can have a substantially flat upper surface, thus facilitating the electrical connection between the external lines or electrodes described later and the light-emitting stack structure. According to an embodiment of this disclosure, as is known in the art, the light-emitting element 100 includes a surface area of ​​approximately less than 10,000 μm. 2In the case of micro-LEDs, or in another embodiment with a surface area of ​​less than 4000 μm 2 Or 2500μm 2 In the case of a micro LED, as shown in the figure, the connecting electrodes 20ce, 30ce, 40ce, and 50ce can overlap with a portion of at least one of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40. More specifically, the connecting electrodes 20ce, 30ce, 40ce, and 50ce can overlap with at least one step formed on the side of the light-emitting stack structure. As described above, since the area of ​​the lower surface of the connecting electrodes is larger than the area of ​​the upper surface, a larger contact area can be formed between the connecting electrodes 20ce, 30ce, 40ce, and 50ce and the light-emitting stack structure. Accordingly, the connecting electrodes 20ce, 30ce, 40ce, and 50ce can be formed more stably on the light-emitting stack structure. In this way, the structure of the light-emitting element 100 can be strengthened with a larger contact area between the connecting electrodes 20ce, 30ce, 40ce, and 50ce and the light-emitting stack structure. Furthermore, since the connecting electrodes 20ce, 30ce, 40ce, and 50ce can overlap with at least one step formed on the side of the light-emitting stack structure, the heat generated from the light-emitting stack structure can be dissipated to the outside more effectively.

[0083] In an exemplary embodiment, at least one of the connecting electrodes 20ce, 30ce, 40ce, and 50ce may overlap with the side of each of the light-emitting stacks 20, 30, and 40, thereby effectively dissipating heat generated internally from the light-emitting stacks 20, 30, and 40 to the outside. Furthermore, when the connecting electrodes 20ce, 30ce, 40ce, and 50ce comprise a reflective material such as metal, they may reflect light emitted from at least one of the light-emitting stacks 20, 30, and 40, thereby improving luminous efficiency.

[0084] Typically, during manufacturing, an array of multiple light-emitting elements can be formed on a substrate 11. The substrate 11 is cut along dicing lines to make each light-emitting element independent (separate), and for additional processing such as encapsulation, the light-emitting elements can be transferred to another substrate or strip using various transfer techniques. In this case, if the light-emitting element includes connecting electrodes such as metal bumps or pillars protruding outwards from the light-emitting structure, various problems may occur during subsequent processes (e.g., transfer steps) due to the structure of the light-emitting element that exposes the connecting electrodes to the outside. Furthermore, depending on the application, the light-emitting element may include elements with a diameter of approximately less than 10000 μm. 2 Or approximately less than 4000μm 2Or approximately less than 2500μm 2 In the case of miniature LEDs with a large surface area, the handling of the light-emitting element may be more difficult due to the smaller shape factor.

[0085] For example, when the connecting electrode has a substantially long shape, such as a rod, it becomes difficult to transfer the light-emitting element using existing vacuum methods because the light-emitting element cannot have sufficient adsorption area due to the protruding structure of the connecting electrode. Furthermore, during subsequent processes, such as when the connecting electrode comes into contact with the manufacturing apparatus, the exposed connecting electrode can be directly affected by various stresses, which may damage the structure of the light-emitting element. As another example, when transferring the light-emitting element by attaching adhesive tape to the upper surface of the light-emitting element (e.g., the surface opposite the substrate), the contact area between the light-emitting element and the adhesive tape may be limited to the upper end surface of the connecting electrode. In this case, unlike when the adhesive tape is attached to the lower surface of the light-emitting element (e.g., the substrate), the adhesion of the light-emitting element to the adhesive tape may be weakened, and during transfer, undesirably, the light-emitting element may detach from the adhesive tape. As yet another example, when transferring the light-emitting element using existing pick-and-place methods, the ejector pins directly contact a portion of the light-emitting element arranged between the connecting pins, which may damage the upper structure of the light-emitting structure. In particular, the ejector pin may strike the center of the light-emitting element and may cause physical damage to the upper light-emitting stack of the light-emitting element.

[0086] According to one embodiment of this disclosure, the protective layer 90 may be formed on the light-emitting stack structure. More specifically, as Figure 1aAs shown, a protective layer 90 may be formed between the connecting electrodes 20ce, 30ce, 40ce, and 50ce, at least covering the sides of the light-emitting stack structure. According to the illustrated embodiment, the protective layer 90 may expose the sides of the substrate 11, the first insulating layer 81, the second insulating layer 83, and the third light-emitting stack 40. The protective layer 90 may be formed substantially parallel to the upper surfaces of the connecting electrodes 20ce, 30ce, 40ce, and 50ce, and may comprise an epoxy molding compound (EMC), which may be formed in various colors (such as black, white, or transparent). However, this disclosure is not limited thereto. For example, in some embodiments, the protective layer 90 may comprise a polyimide (PID), in which case, when the PID is applied to the light-emitting stack structure, it is provided as a dry film rather than a liquid form to increase flatness. In some embodiments, the protective layer 90 may comprise a photosensitive material. In this way, the protective layer 90 not only protects the light-emitting structure from external impacts that may be applied during subsequent processes, but also provides sufficient contact area for the light-emitting element 100, making processing easier during subsequent transfer steps. Furthermore, the protective layer 90 prevents light leakage from the sides of the light-emitting element 100, thereby preventing or at least suppressing interference from light emitted from adjacent light-emitting elements 100.

[0087] Figure 2 This is a schematic cross-sectional view of a light-emitting stacked structure according to an embodiment of the present disclosure. The light-emitting stacked structure according to the illustrated embodiment is substantially the same as the light-emitting stacked structure included in the aforementioned light-emitting element 100; therefore, to avoid repetition, a description of the configuration forming the substantially identical light-emitting stacked structure is omitted. Furthermore, although the first upper contact electrode 21n is not shown, it can ultimately be provided on the first conductive semiconductor layer 21.

[0088] Reference Figure 2 According to an embodiment of this disclosure, the first lower contact electrode 25p, the second lower contact electrode 35p, and the third lower contact electrode 45p are respectively connected to a separate line S. R S G S B The first conductive semiconductor layer 21 of the first light-emitting stack 20, the first conductive semiconductor layer 31 of the second light-emitting stack 30, and the first conductive semiconductor layer 41 of the third light-emitting stack 40 can be connected to a common line S. C Common line S C The first conductive semiconductor layer 21 of the first light-emitting stack 20 can be connected via the first upper contact electrode 21n. Furthermore, the common line S... CThey can be connected to the second adhesive layer 63 and are electrically connected to the first conductive semiconductor layers 31 and 41.

[0089] One embodiment of this disclosure employs an n-common structure, allowing different voltages to be applied to the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40. For example, a relatively lower voltage can be applied to the first light-emitting stack 20, which emits red light, compared to the second and third light-emitting stacks 30 and 40, which emit blue and green light, respectively. Therefore, voltage sources suitable for each light-emitting stack can be used individually, thereby reducing power loss. In the exemplary embodiment shown, a separate line S can be used... R S G S B The first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 are individually controlled by the common line Sc, thereby enabling the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 to selectively emit light.

[0090] A light-emitting stack structure according to an embodiment of the present disclosure can display multiple colors of light according to the operating states of each light-emitting stack 20, 30, 40. In contrast, conventional light-emitting elements utilize multiple light-emitting units that emit a single color of light to display multiple colors of light. More specifically, conventional light-emitting elements typically include light-emitting units spaced apart along a two-dimensional plane and emitting different colors of light (e.g., red, green, and blue) to achieve full-color display. Thus, they may occupy a large area due to conventional light-emitting units. However, the light-emitting stack structure according to an embodiment of the present disclosure can stack multiple light-emitting stacks 20, 30, 40 to emit different colors of light, thereby providing a high level of integration and achieving full-color display with a smaller area than conventional light-emitting devices.

[0091] Furthermore, when the light-emitting element 100 is mounted on another substrate for manufacturing a display device, the number of mounted elements can be significantly reduced compared to the number of existing light-emitting elements. In this way, especially when hundreds of thousands or millions of pixels are formed in a display device, the manufacturing of display devices using the light-emitting element 100 can be substantially simplified.

[0092] According to exemplary embodiments, to improve the purity and efficiency of light emitted from the light-emitting stack structure, the light-emitting stack structure may further include various additional constituent elements. For example, in some exemplary embodiments, wavelength-passing filters may be arranged between the light-emitting stack members. In some embodiments, to balance the brightness of light between the light-emitting stack members, unevenness may be formed on the light-emitting surface of at least one light-emitting stack member. For example, to make the RGB light intensity mixing ratio close to 3:6:1, it is necessary to increase the light intensity of green light; therefore, unevenness may also be formed in the second conductive semiconductor layer 45.

[0093] Hereinafter, a method for forming a light-emitting element 100 according to an embodiment of the present disclosure will be described with reference to the accompanying drawings.

[0094] Figure 3a , Figure 4a , Figure 5a , Figure 6a , Figure 7a and Figure 8a This illustrates the manufacture according to an exemplary embodiment. Figure 1a A plan view of the process of the light-emitting element. Figure 3b , Figure 4b , Figure 5b , Figure 6b , Figure 7b and Figure 8b It is along the exemplary embodiment Figure 3a , 4a The cross-sectional view of the AA′ line of the corresponding plan view shown in 5a, 6a, 7a and 8a. Figure 3c , Figure 4c , Figure 5c , Figure 6c , Figure 7c and Figure 8c It is along the exemplary embodiment Figure 3a , 4a The BB′ line cross-section of the corresponding plan view shown in 5a, 6a, 7a and 8a.

[0095] Refer again Figure 2The first conductive semiconductor layer 41, the third active layer 43, and the second conductive semiconductor layer 45 of the third light-emitting stack 40 can be sequentially grown on a growth substrate (not shown) using methods such as metal-organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE). For example, the third lower contact electrode 45p can be formed on the second conductive semiconductor layer 45 by physical vapor deposition or chemical vapor deposition, and can include a transparent conductive oxide (TCO) such as SnO, InO2, ZnO, ITO, or ITZO. In the case where the third light-emitting stack 40 emits green light according to an embodiment of the present disclosure, the growth substrate can include Al2O3 (e.g., a sapphire substrate), and the third lower contact electrode 45p can include a transparent conductive oxide (TCO) such as tin oxide.

[0096] Subsequently, the substrate 11 can be attached to the third light-emitting stack 40 by placing the adhesive layer 65 between it and the third light-emitting stack 40. The growth substrate can be removed from the third light-emitting stack 40 by means of laser lift-off or the like. As the growth substrate is removed, the first conductive semiconductor layer 41 can be exposed, and a transparent conductive oxide layer 41n, such as ITO, can be formed on the exposed first conductive semiconductor layer 41.

[0097] The second light-emitting stack 30 can also be formed through a process similar to that of the third light-emitting stack 40, and a transparent conductive oxide layer 31n, such as ITO, can be formed on the first conductive semiconductor layer 31 after the growth substrate is removed.

[0098] In addition, the transparent conductive oxide layer 41n on the third light-emitting stack 40 and the transparent conductive oxide layer 31n on the second light-emitting stack 30 can be bonded to each other to form a bonding layer 63, and the temporary substrate on the second light-emitting stack 30 can be removed.

[0099] Furthermore, the first light-emitting stack 20 can be similarly formed by sequentially growing a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer on a growth substrate. For example, a lower contact electrode including a transparent conductive oxide (TCO) can be formed on the second conductive semiconductor layer 25 by physical vapor deposition or chemical vapor deposition. Moreover, the first light-emitting stack 20 can be bonded to the second light-emitting stack 30 by placing a first adhesive layer 61 between it and the second light-emitting stack 30, and the growth substrate can be removed by chemical or mechanical processes.

[0100] In this embodiment, although it is described that the second light-emitting stack 30 and the third light-emitting stack 40 are combined first, followed by the first light-emitting stack 20 being combined with the second light-emitting stack 30, these orders can be changed. For example, the first light-emitting stack 20 and the second light-emitting stack 30 can be combined first, followed by the third light-emitting stack 40 being combined with the second light-emitting stack 30.

[0101] Subsequently, referring to Figure 3a , Figure 3b and Figure 3c Various portions of each of the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 can be patterned using etching processes, thereby exposing a portion of the first conductive semiconductor layer 21, the first lower contact electrode 25p, the second lower contact electrode 35p, the third lower contact electrode 45p, and the second adhesive layer 63. Alternatively, the second adhesive layer 63 can be replaced by exposing a portion of the first conductive semiconductor layer 31 or the first conductive semiconductor layer 41. According to the illustrated embodiment, the first light-emitting stack 20 has the smallest area among the light-emitting stacks 20, 30, and 40. Conversely, the third light-emitting stack 40 can have the largest area among the light-emitting stacks 20, 30, and 40, thus relatively increasing the luminous intensity of the third light-emitting stack 40. However, the concept of this disclosure is not particularly limited to the relative sizes of the light-emitting stacks 20, 30, and 40.

[0102] Reference Figure 4a , Figure 4b and Figure 4c To form the first upper contact electrode 21n, a portion of the upper surface of the first conductive semiconductor layer 21 of the first light-emitting stack 20 can be patterned by wet etching. As described above, for example, the first upper contact electrode 21n can be formed to a thickness of about 100 nm in the recessed region of the first conductive semiconductor layer 21, thereby improving the ohmic contact between them.

[0103] Reference Figure 5a , Figure 5b as well as Figure 5cThe first insulating layer 81 can be formed to cover the light-emitting stack 20, 30, and 40, and a portion of the first insulating layer 81 can be removed to form the first contact hole 20CH, the second contact hole 30CH, the third contact hole 40CH, and the fourth contact hole 50CH. The first contact hole 20CH is defined on the first lower contact electrode 25p, exposing a portion of the first lower contact electrode 25p. The second contact hole 30CH can be defined on the second lower contact electrode 35p, exposing a portion of the second lower contact electrode 35p. The third contact hole 40CH can be defined on the third lower contact electrode 45p, exposing a portion of the third lower contact electrode 45p.

[0104] The fourth contact hole 50CH provides a pathway for allowing electrical connection to the first conductive semiconductor layer 21 of the first light-emitting stack 20, the first conductive semiconductor layer 31 of the second light-emitting stack 30, and the first conductive semiconductor layer 41 of the third light-emitting stack 40. The fourth contact hole 50CH may include a first sub-contact hole 50CHa and a second sub-contact hole 50CHb. The first sub-contact hole 50CHa may be defined on the first conductive semiconductor layer 21 to expose a portion of the first upper contact electrode 21n, and the second sub-contact hole 50CHb may be defined on the second adhesive layer 63 to expose a portion of the second adhesive layer 63.

[0105] Reference Figure 6a , Figure 6b and Figure 6c The first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd are formed on a first insulating layer 81 having a first contact hole 20CH, a second contact hole 30CH, a third contact hole 40CH, and a fourth contact hole 50CH. For example, the first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd can be formed by forming a conductive layer substantially on the entire surface of the substrate and patterning the conductive layer using a photolithography process.

[0106] The first pad 20pd can be formed to overlap with the area where the first contact hole 20CH is formed, thereby connecting to the first lower contact electrode 25p through the first contact hole 20CH. The second pad 30pd can be formed to overlap with the area where the second contact hole 30CH is formed, thereby connecting to the second lower contact electrode 35p through the second contact hole 30CH. The third pad 40pd can be formed to overlap with the area where the third contact hole 40CH is formed, thereby connecting to the third lower contact electrode 45p through the third contact hole 40CH. The fourth pad 50pd is formed to overlap with the area where the fourth contact hole 50CH is formed, especially with the areas where the first sub-contact hole 50CH1 and the second sub-contact hole 50CH2b are formed, thereby being electrically connected to the first conductive semiconductor layer 21 of the first light-emitting stack 20, the first conductive semiconductor layer 31 of the second light-emitting stack 30, and the first conductive semiconductor layer 41 of the third light-emitting stack 40.

[0107] Reference Figure 7a , 7b and Figure 7c The second insulating layer 83 may be formed on the first insulating layer 81. The second insulating layer 83 may include silicon oxide and / or silicon nitride. However, this disclosure is not limited thereto; in some embodiments, the first insulating layer 81 and the second insulating layer 83 may include inorganic materials. Subsequently, the second insulating layer 83 may be patterned to form a first through-hole 20ct, a second through-hole 30ct, a third through-hole 40ct, and a fourth through-hole 50ct exposing the first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd.

[0108] A first through-hole 20ct formed on the first pad 20pd exposes a portion of the first pad 20pd. A second through-hole 30ct formed on the second pad 30pd exposes a portion of the second pad 30pd. A third through-hole 40ct formed on the third pad 40pd exposes a portion of the third pad 40pd. A fourth through-hole 50ct formed on the fourth pad 50pd exposes a portion of the fourth pad 50pd. In the exemplary embodiment shown, the first through-hole 20ct, the second through-hole 30ct, the third through-hole 40ct, and the fourth through-hole 50ct can be defined respectively within the regions where the first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd are formed.

[0109] Reference Figure 8a , Figure 8b and Figure 8cA first connecting electrode 20ce, a second connecting electrode 30ce, a third connecting electrode 40ce, and a fourth connecting electrode 50ce are formed on a second insulating layer 83 having a first through hole 20ct, a second through hole 30ct, a third through hole 40ct, and a fourth through hole 50ct. The first connecting electrode 20ce can be formed to overlap with the area having the first through hole 20ct, thereby connecting to the first pad 20pd through the first through hole 20ct. The second connecting electrode 30ce can be formed to overlap with the area having the second through hole 30ct, thereby connecting to the second pad 30pd through the second through hole 30ct. The third connecting electrode 40ce can be formed to overlap with the area having the third through hole 40ct, thereby connecting to the third pad 40pd through the third through hole 40ct. The fourth connecting electrode 50ce can be formed to overlap with the area having the fourth through hole 50ct, thereby connecting to the fourth pad 50pd through the fourth through hole 50ct.

[0110] The first connecting electrode 20ce, the second connecting electrode 30ce, the third connecting electrode 40ce, and the fourth connecting electrode 50ce can be spaced apart from each other and can be formed on the light-emitting stack structure. The first connecting electrode 20ce, the second connecting electrode 30ce, the third connecting electrode 40ce, and the fourth connecting electrode 50ce can be electrically connected to the first pad 20pd, the second pad 30pd, the third pad 40pd, and the fourth pad 50pd, respectively, so that external signals can be transmitted to each of the light-emitting stacks 20, 30, and 40.

[0111] The method for forming the first connecting electrode 20ce, the second connecting electrode 30ce, the third connecting electrode 40ce, and the fourth connecting electrode 50ce is not particularly limited. For example, according to one embodiment of this disclosure, a seed layer is deposited as a conductive surface on the light-emitting stack structure, and a photoresist pattern can be formed at the location where the connecting electrodes are formed to expose the seed layer. According to one embodiment, the seed layer can be approximately The thickness of the deposition is not limited to this. Subsequently, the seed layer can be plated using metals such as Cu, Ni, Ti, Sb, Zn, Mo, Co, Sn, Ag, or alloys thereof, and the photoresist pattern and seed layer remaining between the interconnect electrodes can be removed. In some exemplary embodiments, to prevent or at least suppress oxidation of the gold-plated metal, additional metal is deposited or plated onto the plating metal (e.g., the interconnect electrodes) using electroless nickel immersion gold (ENIG). In some embodiments, the seed layer may remain on each interconnect electrode.

[0112] According to the exemplary embodiments shown, the respective connecting electrodes 20ce, 30ce, 40ce, and 50ce may have substantially elongated shapes in a direction away from the substrate 11. In another exemplary embodiment, to reduce stress caused by the elongated shapes of the connecting electrodes 20ce, 30ce, 40ce, and 50ce, the connecting electrodes 20ce, 30ce, and 40ce may comprise two or more metals or multiple different metal layers. However, this disclosure is not limited to the specific shapes of the connecting electrodes 20ce, 30ce, 40ce, and 50ce; in some embodiments, the connecting electrodes may have various shapes.

[0113] As shown in the figure, to facilitate electrical connections between the light-emitting stack structure and external lines or electrodes, each connecting electrode 20ce, 30ce, 40ce, and 50ce can have a substantially flat upper surface. The connecting electrodes 20ce, 30ce, 40ce, and 50ce can overlap with at least one step formed on the side of the light-emitting stack structure. In this way, the lower surface of the connecting electrodes can have a greater width than the upper surface, and a larger contact area is provided between the connecting electrodes 20ce, 30ce, 40ce, and 50ce and the light-emitting stack structure, thereby giving the light-emitting element 100 a more stable structure capable of withstanding various subsequent processes along with the protective layer 90. In this case, the length of the outer side of the connecting electrodes 20ce, 30ce, 40ce, and 50ce and the length of the other surface facing the center of the light-emitting element can be different from each other. For example, the length difference between the two opposing surfaces of the connecting electrodes can be from 3 μm to 16 μm, but is not limited to this.

[0114] Additionally, a protective layer 90 is disposed between the connecting electrodes 20ce, 30ce, 40ce, and 50ce. The protective layer 90 can be formed by a polishing process to be substantially parallel to the upper surfaces of the connecting electrodes 20ce, 30ce, 40ce, and 50ce. According to one embodiment, the protective layer 90 may include epoxy molding compound (EMC), but is not limited thereto. For example, in some embodiments, the protective layer 90 may include photosensitive polyimide (PID). In this way, the protective layer 90 not only protects the light-emitting structure from external impacts that may act during subsequent processes, but also provides sufficient contact area for the light-emitting element 100 to facilitate pickup during subsequent transfer steps. Furthermore, the protective layer 90 prevents light leakage from the sides of the light-emitting element 100, thereby preventing or at least suppressing interference from light emitted from adjacent light-emitting elements 100.

[0115] Multiple light-emitting elements 100 can be formed on a substrate 11, and these light-emitting elements 100 can be divided into individual light-emitting elements through a single process. In one embodiment, after forming a protective layer 90 on the substrate 11, the substrate 11 can be divided together with the protective layer 90 using laser cutting and separation techniques to manufacture the light-emitting elements 100. In another embodiment, after forming the protective layer 90, the substrate 11 and the third adhesive layer 65 can be separated and the protective layer 90 can be divided to manufacture individual light-emitting elements 100.

[0116] Multiple light-emitting elements 100 can be attached to tape or the like before being divided. After being divided into individual light-emitting elements, the tape can be expanded to spatially separate the light-emitting elements 100 from each other.

[0117] Figure 9a and Figure 9b These are schematic cross-sectional and plan views used to illustrate a light-emitting package according to an exemplary embodiment.

[0118] According to one embodiment of this disclosure, the uniform light-emitting element 100 can be first transferred onto a carrier substrate (not shown) for arrangement. In this case, when the light-emitting element 100 includes connecting electrodes protruding outward from the light-emitting stack structure, as described above, various problems arise in subsequent processes due to the non-uniform structure, especially in the transfer process. Furthermore, the light-emitting element includes electrodes with a diameter of approximately less than 10,000 μm, depending on its application. 2 Or approximately less than 4000μm 2 Or approximately less than 2500μm 2 In the case of miniature LEDs with large surface areas, handling the light-emitting elements can be more difficult due to shape factors. However, the provision of a light-emitting element 100 according to an exemplary embodiment, with a protective layer 90 arranged between the connecting electrodes 20ce, 30ce, 40ce, and 50ce, not only makes it easier to pick up the light-emitting element 100 during subsequent processes such as transfer printing and encapsulation, but also protects the light-emitting structure from external impacts and prevents light interference between adjacent light-emitting elements 100.

[0119] The light-emitting element 100 can be attached to the substrate by placing the adhesive layer between it and the substrate. The carrier substrate is not particularly restricted as long as the light-emitting element 100 can be stably mounted on it.

[0120] The light-emitting element 100, attached to the carrier substrate, can be mounted on the circuit board 11p. According to one embodiment, the circuit board 11p may include an upper circuit electrode 11pa, a lower circuit electrode 11pc, and an intermediate circuit electrode 11pb electrically connected to each other. The upper circuit electrode 11pa may correspond to the first connecting electrode 20ce, the second connecting electrode 30ce, the third connecting electrode 40ce, and the fourth connecting electrode 50ce, respectively. In an exemplary embodiment, the upper circuit electrode 11pa is surface-treated with electroless nickel-gold to locally melt at high temperatures, thereby facilitating the electrical connection to the connecting electrodes of the light-emitting element 100.

[0121] According to the illustrated embodiment, preferably, the spacing P of the upper circuit electrodes (refer to) of the circuit board 11p to be mounted to the final target device such as a display device is taken into consideration. Figure 9b The light-emitting elements 100 are spaced apart from each other on the carrier substrate at the required spacing.

[0122] According to one embodiment of this disclosure, for example, the first connecting electrode 20ce, the second connecting electrode 30ce, the third connecting electrode 40ce, and the fourth connecting electrode 50ce of each light-emitting element 100 can be bonded to the upper circuit electrode 11pa of the circuit board 11p by means of anisotropic conductive film (ACF). When the light-emitting element 100 is bonded to the circuit board by ACF bonding performed at a lower temperature than other bonding methods, the light-emitting element 100 can be prevented from being exposed to high temperatures during bonding. However, this disclosure is not limited to a particular bonding method. For example, in some exemplary embodiments, the light-emitting element 100 can be bonded to the circuit board 11p using anisotropic conductive paste (ACP), solder, ball grid array (BGA), or micro-protrusions including at least one of Cu and Sn. In this case, since the upper surfaces of the connecting electrodes 20ce, 30ce, 40ce, and 50ce and the protective layer 90 are substantially parallel to each other through a grinding process, the adhesion of the light-emitting element 100 to the anisotropic conductive adhesive film is increased, thereby forming a more stable structure when bonded to the circuit board 11p.

[0123] Subsequently, a molding layer 91 is formed between the light-emitting elements 100. According to one embodiment, the molding layer 91 can reflect or absorb light emitted from the light-emitting elements 100, thereby blocking light. In particular, the molding layer 91 can be parallel to the upper surface (i.e., the light-emitting surface) of the light-emitting element 100, thereby reducing the pointing angle of light emitted from the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40. For example, the molding layer 91 can cover the side surface of the substrate 11 and can be parallel to the upper surface of the substrate 11. Therefore, the molding layer 91 can prevent light from emitting from the side surface of the substrate 11, thereby reducing the pointing angle. In particular, since the light-emitting surface is limited to the upper surface of the substrate 11, the pointing angles of light from the first light-emitting stack 20, the second light-emitting stack 30, and the third light-emitting stack 40 are substantially the same. Furthermore, the molding layer 91, together with the protective layer 90 formed on the light-emitting element 100, strengthens its structure, thereby providing additional protection for the light-emitting package.

[0124] In exemplary embodiments, the molding layer may comprise an organic or inorganic polymer. In some embodiments, the molding layer 91 may be supplemented with a filler comprising, for example, silica or alumina. As an exemplary embodiment, the molding layer 91 may comprise the same material as the protective layer 90. The molding layer 91 may be formed by a variety of methods known in the art, such as lamination, gold plating, and / or printing. For example, the molding layer 91 may be formed by a vacuum lamination process in which an organic polymer sheet is disposed on the light-emitting element 100 and subjected to high temperature and high pressure in a vacuum to provide a substantially flat upper surface of the light-emitting package, thereby improving light uniformity. The molding layer 91 may be partially removed by a grinding process or a full-surface etching process to expose the upper surface of the light-emitting element 100.

[0125] In some embodiments, when the substrate 11 is removed from the light-emitting element 100, the molding layer 91 may cover the side of the third lower contact electrode 45p and expose the upper surface of the third lower contact electrode 45p.

[0126] In this embodiment, the upper surface of the molding layer 91 is shown and described side by side with the upper surface of the light-emitting element 100; however, a portion of the molding layer 91 may also cover the upper surface of the light-emitting element 100. This can prevent light entering from the outside from being reflected by the light-emitting element 100.

[0127] In addition, the light-emitting element 100 arranged on the circuit board 11p can be cut into the required configuration to form a light-emitting package 110. Figure 9bFour light-emitting elements 100 (2×2) are shown arranged on a circuit board 11p. However, this disclosure is not limited to a specific number of light-emitting elements formed on the light-emitting package 110. For example, in some embodiments, the light-emitting package 110 may include more than one light-emitting element 100 formed on the circuit board 11p. Furthermore, this disclosure is not limited to a specific arrangement of more than one light-emitting element 100 within the light-emitting package 110; for example, more than one light-emitting element 100 within the light-emitting package 110 may be arranged in an n×m arrangement. Here, n and m are positive integers. According to one embodiment, the circuit board 11p may include scan lines and data lines for independently driving each light-emitting element 100 contained in the light-emitting package 110.

[0128] Figure 10 This is a schematic cross-sectional view used to illustrate a display device according to an embodiment of the present disclosure.

[0129] Reference Figure 10 The display device may include a display substrate 11b and a light-emitting package 110. The light-emitting package 110 may be mounted on the display substrate 11b of a final device, such as the display device. The display substrate 11b may include target electrodes 11s corresponding to the lower circuit electrodes 11pc of the light-emitting package 110. The display device according to this disclosure may include a plurality of pixels, and each light-emitting element 100 may be arranged to correspond to each pixel. More specifically, each light-emitting stack of the light-emitting element 100 according to this disclosure may correspond to each sub-pixel of a pixel. The light-emitting element 100 may include vertically stacked light-emitting stacks 20, 30, and 40, thereby substantially reducing the number of elements transferred for each sub-pixel compared to the number of conventional light-emitting elements. Furthermore, since the lengths of the opposing surfaces of the connecting electrodes may be different, the connecting electrodes can be stably formed in the light-emitting stack structure to strengthen the internal structure. Furthermore, since the light-emitting element 100 according to a certain embodiment may include a protective layer 90 between the connecting electrodes, the light-emitting element 100 can be protected from external impacts.

[0130] In this embodiment, although the case of the light-emitting package 110 being mounted on the display substrate 11b is described, the process of manufacturing the light-emitting package 110 may be omitted, and the light-emitting element 100 may be directly mounted on the display substrate 11b to form the molding layer 91.

[0131] Figure 11 This is a schematic cross-sectional view used to illustrate a light-emitting package according to yet another embodiment of the present disclosure.

[0132] Reference Figure 11 The light-emitting package according to this embodiment is the same as the one described above. Figure 9a and Figure 9bThe described light-emitting package is generally similar, but the difference is that the light-emitting element 200 does not include the substrate 11. The substrate 11 and the third adhesive layer 65 are removed from the light-emitting element 100, thereby exposing the third lower contact electrode 45p. The light-emitting element 200 emits light through the upper surface of the third lower contact electrode 45p; therefore, the upper surface of the third lower contact electrode 45p becomes the light-emitting surface. The molding layer 91 covers the side of the third lower contact electrode 45p and exposes its surface.

[0133] Figure 12 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0134] Reference Figure 12 According to this embodiment, the light-emitting stacked structure and Figure 2 The light-emitting stacked structures are generally similar, with the difference being the positions of the first conductive semiconductor layer 21 and the second conductive semiconductor layer 25 of the first light-emitting stack 20. That is, in this embodiment, the first conductive semiconductor layer 21 is arranged closer to the second light-emitting stack 30 than the second conductive semiconductor layer 25. In addition, the first upper contact electrode 21n is arranged at the lower part of the first conductive semiconductor layer 21, and the first lower contact electrode 25p is arranged on the second conductive semiconductor layer 25.

[0135] Single line S R S G S B They can be electrically connected to the first lower contact electrode to the third lower contact electrode 25p, 35p, and 45p respectively, and share a common line S. C It can be electrically connected to the first upper contact electrode 21n and the second adhesive layer 63. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common n-light-emitting stack structure.

[0136] Figure 13 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0137] Reference Figure 13 According to this embodiment, the light-emitting stacked structure and Figure 2 The light-emitting stacked structures are largely similar, the difference being that the first adhesive layer 61a includes a conductive material. That is, in Figure 2In one embodiment, the second adhesive layer 63 comprises a conductive material to electrically connect the first conductive semiconductor layers 31 and 41 to each other. However, in this embodiment, the first adhesive layer 61a comprises a conductive material to electrically connect the first conductive semiconductor layers 21 and 31 to each other. For example, the first adhesive layer 61a may be a bonding layer between the first upper contact electrode 21n and the second upper contact electrode 31n, wherein the first upper contact electrode 21n and the second upper contact electrode 31n may be formed using a transparent conductive oxide layer such as ITO. In addition, the second adhesive layer 63a is formed using an insulating material, therefore, the third light-emitting stack 40 is insulated from the second light-emitting stack 30 by the second adhesive layer 63a.

[0138] Single line S R S G S B They can be electrically connected to the first lower contact electrode to the third lower contact electrode 25p, 35p, and 45p respectively, with a common line S. C It can be electrically connected to the first adhesive layer 61a and the first conductive semiconductor layer 41. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common n-light-emitting stack structure.

[0139] Figure 14 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0140] Reference Figure 14 According to this embodiment, the light-emitting stacked structure and Figure 13 The light-emitting stacked structures are generally similar, with the difference being the positions of the first conductive semiconductor layer 41 and the second conductive semiconductor layer 45 of the third light-emitting stack 40. That is, in this embodiment, the second conductive semiconductor layer 45 is arranged closer to the second light-emitting stack 30 than the first conductive semiconductor layer 41. In addition, the third lower contact electrode 45p is arranged on the second conductive semiconductor layer 45.

[0141] In this embodiment, the substrate 141 may be a growth substrate for growing the third light-emitting stack 40, and the first conductive semiconductor layer 41 may be grown on the substrate 141. Therefore, the third adhesive layer 65 described in the previous embodiments is omitted in this embodiment.

[0142] Single line S R S G S B They can be electrically connected to the first lower contact electrode to the third lower contact electrode 25p, 35p, and 45p respectively, with a common line S. C It can be electrically connected to the first adhesive layer 61a and the first conductive semiconductor layer 41. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common n-light-emitting stack structure.

[0143] Figure 15 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0144] Reference Figure 15 According to this embodiment, the light-emitting stacked structure and Figure 2 The light-emitting stacked structures are generally similar, except that the second adhesive layer 63b connects the second conductive semiconductor layer 35 of the second light-emitting stack 30 with the second conductive semiconductor layer 45 of the third light-emitting stack 40, and the substrate 141 can be a growth substrate for growing the third light-emitting stack 40.

[0145] In one embodiment, the second adhesive layer 63b may be a bonding layer between the second lower contact electrode 35p and the third lower contact electrode 45p, and the second lower contact electrode 35p and the third lower contact electrode 45p may be transparent conductive oxide layers such as ITO.

[0146] Single line S R S G S B They can be electrically connected to the first conductive semiconductor layers 21, 31, and 41 respectively, with a common line S. C Both can be electrically connected to the first lower contact electrode 25p and the second adhesive layer 63b. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common p-shaped light-emitting stack structure.

[0147] Figure 16 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0148] Reference Figure 16 According to this embodiment, the light-emitting stacked structure and Figure 15 The light-emitting stacked structures are generally similar, with the difference being the positions of the first conductive semiconductor layer 21 and the second conductive semiconductor layer 25 of the first light-emitting stack 20. That is, in this embodiment, the first conductive semiconductor layer 21 is arranged closer to the second light-emitting stack 30 than the second conductive semiconductor layer 25. In addition, the first upper contact electrode 21n is arranged at the lower part of the first conductive semiconductor layer 21, and the first lower contact electrode 25p is arranged on the second conductive semiconductor layer 25.

[0149] Single line S R S G S B They can be electrically connected to the first conductive semiconductor layers 21, 31, and 41 respectively, with a common line S. CBoth can be electrically connected to the first lower contact electrode 25p and the second adhesive layer 63b. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common p-shaped light-emitting stack structure.

[0150] Figure 17 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0151] Reference Figure 17 According to this embodiment, the light-emitting stacked structure and Figure 13 The light-emitting stacked structures are generally similar, except that the first adhesive layer 61b electrically connects the second conductive semiconductor layer 25 of the first light-emitting stack 20 with the second conductive semiconductor layer 35 of the second light-emitting stack 30.

[0152] In one embodiment, the first adhesive layer 61b may be a bonding layer of the first lower contact electrode 25p and the second lower contact electrode 35p, and the first lower contact electrode 25p and the second lower contact electrode 35p may be transparent conductive oxide layers such as ITO.

[0153] In this embodiment, a single line S R S G S B They can be electrically connected to the first conductive semiconductor layers 21, 31, and 41 respectively, with a common line S. C Both can be electrically connected to the first adhesive layer 61b and the third lower contact electrode 45p. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common p-shaped light-emitting stack structure.

[0154] Figure 18 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0155] Reference Figure 18 According to this embodiment, the light-emitting stacked structure and Figure 17 The light-emitting stacked structures are generally similar, with the difference being the positions of the first conductive semiconductor layer 41 and the second conductive semiconductor layer 45 of the third light-emitting stack 40. That is, in this embodiment, the second conductive semiconductor layer 45 is arranged closer to the second light-emitting stack 30 than the first conductive semiconductor layer 41. In addition, the third lower contact electrode 45p is arranged on the second conductive semiconductor layer 45.

[0156] In this embodiment, the substrate 141 may be a growth substrate for growing the third light-emitting stack 40, and the first conductive semiconductor layer 41 may be grown on the substrate 141. Therefore, the third adhesive layer 65 described in the previous embodiments is omitted in this embodiment.

[0157] Single line SR S G S B They can be electrically connected to the first conductive semiconductor layers 21, 31, and 41 respectively, with a common line S. C It can be electrically connected to the first adhesive layer 61b and the third lower contact electrode 45p. The light-emitting stack structure according to this embodiment can provide a light-emitting element with a common p-light-emitting stack structure.

[0158] Figure 19 This is a schematic cross-sectional view of a light-emitting stacked structure according to yet another embodiment of the present disclosure.

[0159] Reference Figure 19 According to this embodiment, the light-emitting stacked structure and Figure 12 The light-emitting stacked structure is generally similar, except that the second adhesive layer 63a includes a non-conductive material. The second adhesive layer 63a can transmit light. For example, the second adhesive layer 63a may include an optically transparent adhesive (OCA), which may include epoxy resin, polyimide, SU8, spin-coated glass (SOG), benzocyclobutene (BCB), and is not limited thereto.

[0160] Since the second adhesive layer 63b includes a non-conductive material, the first conductive semiconductor layer 31 of the second light-emitting stack 30 and the first conductive semiconductor layer 41 of the third light-emitting stack 40 are insulated by the second adhesive layer 63b.

[0161] Figure 20a This is a schematic plan view illustrating a light-emitting element according to yet another embodiment of the present disclosure. Figure 20b It is along Figure 20a A schematic cross-sectional view obtained by cutting line AA′. Figure 20c It is along Figure 20a A schematic cross-sectional view obtained by cutting the section line BB′. The light-emitting element can be utilized... Figure 19 It is formed by a stacked structure of light-emitting materials, thus eliminating the need for manufacturing processes.

[0162] Reference Figure 20a , Figure 20b and Figure 20c The light-emitting element according to this embodiment is similar to that of the previously referenced element. Figures 1a to 1d The light-emitting elements 100 described are generally similar; however, differences arise as the second adhesive layer 63a includes a non-conductive material.

[0163] For example, the second sub-contact hole 50CHb of the first insulating layer 81 does not expose a portion of the second adhesive layer 63a, but instead exposes a portion of the first conductive semiconductor layer 31 and a portion of the first conductive semiconductor layer 41 together. By using a single sub-contact hole 50CHb to simultaneously expose the first conductive semiconductor layers 31 and 41, process margins can be increased.

[0164] Furthermore, the fourth pad 50pd can be electrically connected to the first conductive semiconductor layers 31 and 41 through the second sub-contact hole 50CHb, and can also be electrically connected to the first upper contact electrode 21n through the first sub-contact hole 50CHa. The fourth connecting electrode 50ce is connected to the exposed fourth pad 50pd through the through hole 50ct of the second insulating layer 83. Therefore, the fourth pad 50pd can be electrically connected to the first conductive semiconductor layers 21, 31, and 41 together. Accordingly, a light-emitting element with a common n-structure can be provided.

[0165] In this embodiment, Figure 19 The substrate 11 and the third adhesive layer 65 can eventually be removed from the light-emitting element. In another embodiment, the substrate 11 and the third adhesive layer 65 may also remain on the light-emitting element.

[0166] While exemplary embodiments and implementations have been described in this specification, other embodiments and modifications will become apparent from this description. Therefore, this disclosure is not limited to these embodiments, but includes a broader scope of protection beyond the foregoing claims, as well as diverse modifications and equivalents that will be apparent to those skilled in the art.

Claims

1. A light-emitting element, comprising: The first light-emitting stack includes a first conductive semiconductor layer and a second conductive semiconductor layer; The second light-emitting stack includes a first conductive semiconductor layer and a second conductive semiconductor layer; The third light-emitting stack includes a first conductive semiconductor layer and a second conductive semiconductor layer; A first adhesive layer bonds the first light-emitting stack and the second light-emitting stack. A second adhesive layer is used to bond the second light-emitting stack and the third light-emitting stack. The first connecting electrode is electrically connected to the first light-emitting stack; The second connecting electrode is electrically connected to the second light-emitting stack; The third connecting electrode is electrically connected to the third light-emitting stack; The fourth connecting electrode is electrically connected to the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack. as well as A protective layer surrounds at least a portion of the first connecting electrode to the fourth connecting electrode. The second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack. One of the first adhesive layer and the second adhesive layer is a conductive adhesive layer that electrically connects to the adjacent light-emitting stack. The fourth connecting electrode is electrically connected to the light-emitting stack adjacent to the conductive adhesive layer through the conductive adhesive layer. The fourth connecting electrode is electrically connected to the first conductive semiconductor layer of the first light-emitting stack to the third light-emitting stack. The first conductive semiconductor layer is an n-type semiconductor layer.

2. The light-emitting element according to claim 1, wherein, The conductive adhesive layer includes ITO.

3. The light-emitting element according to claim 1, wherein, The first light-emitting stack, the second light-emitting stack, and the third light-emitting stack emit red light, blue light, and green light, respectively.

4. The light-emitting element according to claim 1, wherein, The protective layer includes epoxy molding compound or polyimide film. The upper surface of the protective layer is parallel to the upper surfaces of the first connecting electrode to the fourth connecting electrode.

5. The light-emitting element according to claim 1, further comprising: The substrate is arranged adjacent to the third light-emitting stack.

6. A display device, comprising: Display substrate; Multiple light-emitting elements are arranged on the display substrate; as well as A molding layer covers the sides of the light-emitting element. The light-emitting element includes: The first light-emitting stack includes a first conductive semiconductor layer and a second conductive semiconductor layer; The second light-emitting stack includes a first conductive semiconductor layer and a second conductive semiconductor layer; The third light-emitting stack includes a first conductive semiconductor layer and a second conductive semiconductor layer; A first adhesive layer bonds the first light-emitting stack and the second light-emitting stack. A second adhesive layer, bonding the second light-emitting stack and the third light-emitting stack; and The fourth connecting electrode is electrically connected to the first light-emitting stack, the second light-emitting stack, and the third light-emitting stack. The second light-emitting stack is disposed between the first light-emitting stack and the third light-emitting stack. One of the first adhesive layer and the second adhesive layer is a conductive adhesive layer that electrically connects to the adjacent light-emitting stack. The fourth connecting electrode is electrically connected to the light-emitting stack adjacent to the conductive adhesive layer through the conductive adhesive layer. The fourth connecting electrode is electrically connected to the first conductive semiconductor layer of the first light-emitting stack to the third light-emitting stack. The first conductive semiconductor layer is an n-type semiconductor layer.

7. The display device according to claim 6, wherein, The conductive adhesive layer includes ITO.

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