Light-emitting element package and application thereof

Abstract

To provide a light-emitting element package.SOLUTION: A light-emitting element package includes a printed circuit board having a front surface and a rear surface, at least one light-emitting element provided on the front surface and emitting light in a direction toward the front surface, and a molding layer provided on the printed circuit board and surrounding the light-emitting element. The light-emitting element includes a light-emitting structure provided on the printed circuit board, a substrate provided on the light-emitting structure, and a number of bump electrodes provided between the light-emitting structure and the printed circuit board. The molding layer may cover an upper surface of the substrate and may have a microscopic uneven part on a surface of the molding layer that is exposed to the outside.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a light emitting device package and its application. [Background technology]

[0002] In recent years, various devices using light emitting diodes (LEDs) have been developed. Devices using light emitting diodes as light sources include general lighting and display devices. Each device using light emitting diodes is obtained by forming red (R), green (G), and blue (B) light emitting diode (LED) structures that are individually grown on a final substrate.

[0003] In order to apply such light emitting diodes to various devices, they must have a simple structure and be easy to manufacture. Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE PREFERRED EMBODIMENTS An object of an embodiment of the present invention is to provide a light emitting device package having a simple structure and a simple manufacturing method, and its application. [Means for solving the problem]

[0005] According to an embodiment of the present invention, a light emitting device package includes a printed circuit board having a front surface and a rear surface, at least one light emitting device disposed on the front surface and emitting light toward the front surface, and a molding layer disposed on the printed circuit board and surrounding the light emitting device, the light emitting device including a light emitting structure disposed on the printed circuit board, a substrate disposed on the light emitting structure, and a plurality of bump electrodes disposed between the light emitting structure and the printed circuit board. The molding layer covers an upper surface of the substrate, and a surface exposed to the outside of the molding layer may be provided with fine unevenness.

[0006] In one embodiment of the present invention, the micro-texture may be manufactured by at least one of plasma treatment, micro-sandblasting, pattern transfer, dry polishing, and wet etching.

[0007] In one embodiment of the invention, the molding layer may have a substantially flat upper surface.

[0008] In one embodiment of the present invention, the molding layer can reflect, scatter, or absorb a portion of external light.

[0009] In one embodiment of the present invention, the molding layer may be filled at least partially between the light emitting structure and the printed circuit board.

[0010] In one embodiment of the present invention, the molding layer may have an external light reflectance, external light scattering, or external light absorptance of about 50% or more.

[0011] In one embodiment of the present invention, the molding layer may have a black color.

[0012] In one embodiment of the present invention, the printed circuit board may include upper electrodes provided on the front surface, lower electrodes provided on the back surface, and via electrodes connecting the upper electrodes and the lower electrodes, and each of the bump electrodes may be connected to a corresponding one of the upper electrodes.

[0013] In an embodiment of the present invention, the distance between two adjacent bottom electrodes may be greater than the distance between two adjacent top electrodes.

[0014] In one embodiment of the present invention, the light emitting element may be provided in a plurality of pieces. For example, the light emitting element may be provided in a number of four pieces, and the light emitting structure of each of the light emitting elements may include a plurality of epitaxial stacks sequentially stacked on the substrate, emitting light in different wavelength bands, and having light emitting regions overlapping each other.

[0015] In one embodiment of the present invention, the plurality of epitaxial stacks may include a first epitaxial stack that emits a first light, a second epitaxial stack provided on the first epitaxial stack that emits a second light in a wavelength band different from the first light, and a third epitaxial stack provided on the second epitaxial stack that emits a third light in a wavelength band different from the first and second lights.

[0016] In one embodiment of the present invention, each of the first to third epitaxial stacks may include a p-type semiconductor layer, an n-type semiconductor layer, and an active layer provided between the p-type semiconductor layer and the n-type semiconductor layer.

[0017] In one embodiment of the present invention, each of the bump electrodes may include a first bump electrode connected to a p-type semiconductor layer of the first epitaxial stack, a second bump electrode connected to a p-type semiconductor layer of the second epitaxial stack, a third bump electrode connected to a p-type semiconductor layer of the third epitaxial stack, and a fourth bump electrode connected to each of the n-type semiconductor layers of the first to third epitaxial stacks.

[0018] In one embodiment of the present invention, each of the light-emitting elements may include first to fourth light-emitting elements, each of the lower electrodes may include first to sixth scan pads and first and second data pads, the first light-emitting element may be connected to the first to third scan pads and the first data pad, the second light-emitting element may be connected to the first to third scan pads and the second data pad, the third light-emitting element may be connected to the fourth to sixth scan pads and the first data pad, and the fourth light-emitting element may be connected to the fourth to sixth scan pads and the second data pad.

[0019] In one embodiment of the present invention, in each light emitting element, each of the bump electrodes may include first to fourth bump electrodes, and first to third scan signals may be applied to the first to third bump electrodes, and a data signal may be applied to the fourth bump electrode.

[0020] In one embodiment of the present invention, the molding layer may be formed by a vacuum laminate method.

[0021] In one embodiment of the present invention, the light emitting device package can be used in a display device or a vehicle lighting device, and in this case, may include a base substrate and at least one light emitting device package provided on the base substrate.

[0022] A light emitting device package according to an embodiment of the present invention may be manufactured by forming each light emitting device, arranging each light emitting device on a printed circuit board, forming a molding layer on the printed circuit board by a vacuum lamination method so as to cover each light emitting device, forming a fine uneven portion on a surface of the molding layer by treating an externally exposed surface of the molding layer, and cutting the printed circuit board and the molding layer to form a light emitting device package. The molding layer covers an upper surface of the substrate and includes a material that reflects, scatters, or absorbs a portion of external light. Effect of the Invention

[0023] According to an embodiment of the present invention, a light emitting device package having a simple structure and a simple manufacturing method can be provided. Also, according to an embodiment of the present invention, a display device using the light emitting device can be provided. [Brief description of the drawings]

[0024] [Figure 1] 1 is a cross-sectional view showing a light emitting device according to an embodiment of the present invention; [Figure 2a] 1 is a plan view specifically illustrating a light emitting device according to an embodiment of the present invention. [Figure 2b] FIG. 2b is a cross-sectional view taken along line AA' in FIG. 2a. [Figure 3a] 1A to 1C are plan views sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 3b] 3A-3C are cross-sectional views taken along line AA' of FIG. 3A, sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 4a] 1A to 1C are plan views sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 4b] 4A to 4C are cross-sectional views taken along line AA' of FIG. 4A, sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 5a] 1A to 1C are plan views sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 5b] 5A to 5C are cross-sectional views taken along line AA' of FIG. 5A, sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 6a] 1A to 1C are plan views sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 6b] 6A to 6C are cross-sectional views taken along line AA' of FIG. 6A, sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 7a] 1A to 1C are plan views sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 7b] 7A to 7C are cross-sectional views taken along line AA' of FIG. 7A, sequentially illustrating a method for manufacturing a light emitting device according to an embodiment of the present invention. [Figure 8a] 1A to 1C are diagrams sequentially illustrating a method for manufacturing a light emitting device package. [Figure 8b] 1A to 1C are diagrams sequentially illustrating a method for manufacturing a light emitting device package. [Figure 8c] 1A to 1C are diagrams sequentially illustrating a method for manufacturing a light emitting device package. [Figure 8d] 1A to 1C are diagrams sequentially illustrating a method for manufacturing a light emitting device package. [Figure 8e] 1A to 1C are diagrams sequentially illustrating a method for manufacturing a light emitting device package. [Figure 9a] 11 is a SEM (scanning electron microscope) photograph showing a molding layer that has been plasma-treated and a molding layer that has not been plasma-treated. [Figure 9b] 11 is a SEM (scanning electron microscope) photograph showing a molding layer that has been plasma-treated and a molding layer that has not been plasma-treated. [Figure 10a] 3A to 3C are cross-sectional views sequentially showing steps of forming a fine concave-convex portion on the surface of a molding layer using an imprint mold. [Figure 10b] 3A to 3C are cross-sectional views sequentially showing steps of forming a fine concave-convex portion on the surface of a molding layer using an imprint mold. [Figure 10c] 3A to 3C are cross-sectional views sequentially showing steps of forming a fine concave-convex portion on the surface of a molding layer using an imprint mold. [Figure 10d] 3A to 3C are cross-sectional views sequentially showing steps of forming a fine concave-convex portion on the surface of a molding layer using an imprint mold. [Figure 10e] 3A to 3C are cross-sectional views sequentially showing steps of forming a fine concave-convex portion on the surface of a molding layer using an imprint mold. [Figure 11a] 1 is a plan view showing a light emitting device package according to an embodiment of the present invention, and is a top view showing four light emitting devices mounted in a matrix on one printed circuit board. [Figure 11b] FIG. 11b is a rear view of the light-emitting device package shown in FIG. [Figure 12] FIG. 11B is a circuit diagram of the light emitting device package shown in FIGS. [Figure 13] 1 is a schematic cross-sectional view showing a light source module manufactured by mounting a number of light emitting device packages on a base substrate for application to a display device, a vehicle lighting device, or the like. [Figure 14] 1 is a plan view conceptually illustrating a case in which a light emitting device package according to an embodiment of the present invention is applied to a display device. [Figure 15] FIG. 15 is an enlarged plan view of a portion P1 in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Since the present invention can be modified in various ways and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text, but it is not intended to limit the present invention to the specific disclosed forms, and it should be understood that the present invention includes all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0026] Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

[0027] The present invention relates to a light emitting device, and more particularly to a light emitting device that emits light. The light emitting device of the present invention can be used as a light source in various devices.

[0028] FIG. 1 is a cross-sectional view showing a light emitting device according to one embodiment of the present invention.

[0029] 1, a light emitting device according to an embodiment of the present invention includes a light emitting structure formed of a plurality of epitaxial stacks stacked in sequence. The light emitting structure is provided on a substrate 11.

[0030] The substrate 11 is provided in the form of a plate having a front surface and a back surface.

[0031] The light emitting structure includes two or more epitaxial stacks, each of which can emit light of a different wavelength band. That is, the light emitting structure includes a plurality of epitaxial stacks, each of which has the same or different energy bands. In this embodiment, the light emitting structure is shown to be composed of three layers in which the epitaxial stacks are sequentially stacked on the front surface of the substrate 11, so that the plurality of epitaxial stacks are stacked in the order of the third epitaxial stack 40, the second epitaxial stack 30, and the first epitaxial stack 20 from the front surface of the substrate 11.

[0032] The substrate 11 may be formed of an optically transparent insulating material.

[0033] The material of the substrate 11 may be provided by one of the growth substrates on which an epitaxial stack, i.e. the third epitaxial stack 40, can be grown, provided on the front side of the substrate 11. In an embodiment of the present invention, the substrate 11 may be sapphire (Al2O3), silicon carbide (SiC), gallium nitride (GaN), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN), aluminum nitride (AlN), gallium oxide (Ga2O3), or a silicon substrate (Si).

[0034] Each epitaxial stack emits light in a direction toward the rear surface of the substrate 11 (downward in FIG. 1). At this time, light emitted from one epitaxial stack travels toward the rear surface of the substrate 11 while passing through other epitaxial stacks positioned in the light path.

[0035] In this embodiment, the first epitaxial stack 20 can emit a first light, the second epitaxial stack 30 can emit a second light, and the third epitaxial stack 40 can emit a third light. Here, the first to third lights can be the same or different lights. In one embodiment of the present invention, the first to third lights can be color lights in the visible light wavelength band.

[0036] In one embodiment of the present invention, the first to third lights may be lights of different wavelength bands having successively shorter wavelengths. That is, the first to third lights may have the same or different wavelength bands, and may be lights of shorter wavelength bands having higher energy from the first light to the third light. In this embodiment, the first light may be red light, the second light may be green light, and the third light may be blue light.

[0037] However, the first to third lights may be lights of different wavelength bands having successively longer wavelengths, or may be lights of different wavelength bands arranged irregularly regardless of wavelength length. In one embodiment, the first light may be red light, the second light may be blue light, and the third light may be green light.

[0038] In the light emitting structure according to an embodiment of the present invention having the above structure, each epitaxial stack is independently connected to a signal line for applying a light emitting signal, thereby driving each epitaxial stack independently. As a result, various colors can be realized by determining whether or not light is emitted from each epitaxial stack. In addition, since epitaxial stacks emitting light of different wavelengths are formed by overlapping each other, it is possible to form the epitaxial stack in a small area.

[0039] More specifically, in an emitting stack according to one embodiment of the present invention, a third epitaxial stack 40 may be provided on a substrate 11, a second epitaxial stack 30 may be provided on the third epitaxial stack 40 with a second adhesive layer 63 sandwiched therebetween, and a first epitaxial stack 20 may be provided on the second epitaxial stack 30 with a first adhesive layer 61 sandwiched therebetween.

[0040] The first and second adhesive layers 61 and 63 may be made of a non-conductive material, and may include a material having optical transparency. For example, an optically clear adhesive may be used for the first and second adhesive layers 61 and 63. However, an embodiment of the present invention is not limited thereto, and the first and second adhesive layers 61 and 63 may be optically transparent to a specific wavelength. For example, the first and second adhesive layers 61 and 63 may be a color filter that shows a predetermined color by transmitting only a specific wavelength. The color may be selected from a variety of colors, and may be, for example, red, blue, or green, or may be a color different therefrom.

[0041] The third epitaxial stack 40 includes an n-type semiconductor layer 41, an active layer 43, and a p-type semiconductor layer 45, which are arranged in this order from bottom to top. The n-type semiconductor layer 41, the active layer 43, and the p-type semiconductor layer 45 of the third epitaxial stack 40 may include a semiconductor material that emits blue light. A third p-type contact electrode 45p is provided on the upper part of the p-type semiconductor layer 45 of the third epitaxial stack 40.

[0042] The second epitaxial stack 30 includes a p-type semiconductor layer 35, an active layer 33, and an n-type semiconductor layer 31, which are arranged in this order from bottom to top. The p-type semiconductor layer 35, the active layer 33, and the n-type semiconductor layer 31 of the second epitaxial stack 30 may include a semiconductor material that emits green light. A second p-type contact electrode 35p is provided on the bottom of the p-type semiconductor layer 35 of the second epitaxial stack 30.

[0043] The first epitaxial stack 20 includes a p-type semiconductor layer 25, an active layer 23, and an n-type semiconductor layer 21, which are arranged in this order from bottom to top. The p-type semiconductor layer 25, the active layer 23, and the n-type semiconductor layer 21 of the first epitaxial stack 20 may include a semiconductor material that emits red light. A first p-type contact electrode 25p may be provided on the bottom of the p-type semiconductor layer 25 of the first epitaxial stack 20.

[0044] A first n-type contact electrode may be provided on the n-type semiconductor layer 21 of the first epitaxial stack 20. The first n-type contact electrode 21n may be made of a single layer or multiple layers of metal. For example, the first n-type contact electrode 21n may be made of various materials including metals such as Al, Ti, Cr, Ni, Au, Ag, Sn, W, Cu, and alloys thereof.

[0045] In this embodiment, the first to third p-type contact electrodes 25p, 35p, 45p may be made of a transparent conductive material so as to be light transmissible.

[0046] In this embodiment, a common wiring may be connected to the n-type semiconductor layers 21, 31, and 41 of the first to third epitaxial stacks 20, 30, and 40. Here, the common wiring is a wiring to which a common voltage is applied. Furthermore, a light emission signal wiring may be connected to the p-type semiconductor layers 25, 35, and 45 of the first to third epitaxial stacks 20, 30, and 40 via p-type contact electrodes 25p, 35p, and 45p, respectively. More specifically, a common voltage S may be applied to the first n-type contact electrode 21n and the second and third n-type semiconductor layers 31 and 41 via a common wiring. C is applied to the p-type contact electrodes 25p, 35p, 45p of the first to third epitaxial stacks 20, 30, 40 via light emission signal wiring, thereby controlling the light emission of the first to third epitaxial stacks 20, 30, 40. Here, the light emission signals are first to third light emission signals S R , S G , S B In one embodiment of the present invention, the first light-emitting signal S R is red light, the second light-emitting signal S G is green light, the third light-emitting signal S B may be a signal corresponding to the emission of blue light.

[0047] According to the above embodiment, the first to third epitaxial stacks 20, 30, 40 are driven by the light emission signal applied to each epitaxial stack. That is, the first epitaxial stack 20 is driven by the first light emission signal S R The second epitaxial stack 30 is driven by a second light emitting signal S G The third epitaxial stack 40 is driven by a third light emitting signal S B Here, the first, second, and third light-emitting signals S R , S G , S B are applied to the first to third epitaxial stacks 20, 30, and 40 independently of one another, so that the first to third epitaxial stacks 20, 30, and 40 are driven independently. The light emitting stack can ultimately provide light of various colors and various amounts by combining the first to third lights emitted downward from the first to third epitaxial stacks 20, 30, and 40.

[0048] In the above embodiment, a common voltage is supplied to the n-type semiconductor layers 21, 31, 41 of the first to third epitaxial stacks 20, 30, 40, and an emission signal is applied to the p-type semiconductor layers 25, 35, 45 of the first to third epitaxial stacks 20, 30, 40, but the embodiment of the present invention is not limited thereto. In another embodiment of the present invention, a common voltage may be supplied to the p-type semiconductor layers 25, 35, 45 of the first to third epitaxial stacks 20, 30, 40, and an emission signal may be applied to the n-type semiconductor layers 21, 31, 41 of the first to third epitaxial stacks 20, 30, 40.

[0049] The light emitting stack according to an embodiment of the present invention having the above structure provides different lights in overlapping regions rather than on separate planes to achieve color, thereby enabling miniaturization and integration of light emitting devices. According to the present invention, light emitting devices embodying different lights are provided as a stack by overlapping parts of the light emitting devices in one region, thereby enabling full color to be achieved in a significantly smaller area than in the conventional invention. This allows a high-resolution device to be manufactured even in a small area. In addition, in the light emitting stack having the above structure, when epitaxial stacks emitting light of the same wavelength band are stacked instead of epitaxial stacks emitting light of different wavelength bands, a light emitting device with variously controlled light intensity can be manufactured.

[0050] In the light emitting stack according to an embodiment of the present invention, a multi-layer epitaxial stack is sequentially laminated on a substrate, and then a contact part is formed on the multi-layer epitaxial stack through a minimum number of processes, and a wiring part is connected. Also, compared to a conventional display device manufacturing method in which light emitting elements of individual colors are separately manufactured and individually mounted, in the present invention, only one light emitting stack is mounted instead of multiple light emitting elements, and therefore the manufacturing method is significantly simplified.

[0051] Since the light emitting device according to an embodiment of the present invention may be realized in various forms, a specific embodiment will be described with reference to FIGS. 2a and 2b.

[0052] FIG. 2a is a plan view specifically illustrating a light emitting device according to an embodiment of the present invention, and FIG. 2b is a cross-sectional view taken along line AA' of FIG. 2a.

[0053] 2a and 2b, a light-emitting device according to an embodiment of the present invention includes a substrate 11, a light-emitting structure provided on the substrate and including a plurality of epitaxial stacks, and bump electrodes 20bp, 30bp, 40bp, and 50bp provided on the light-emitting structure. The light-emitting structure includes a third epitaxial stack 40, a second epitaxial stack 30, and a first epitaxial stack 20 stacked on the substrate 11.

[0054] Each of the first to third epitaxial stacks 20, 30, and 40 includes a p-type semiconductor layer, an n-type semiconductor layer, and an active layer provided between the p-type semiconductor layer and the n-type semiconductor layer. In the drawings, the n-type semiconductor layer, the p-type semiconductor layer, and the active layer of each epitaxial stack are shown as one epitaxial stack.

[0055] A third p-type contact electrode 45p, a second adhesion layer 63, and a second p-type contact electrode 35p are sequentially provided on the third epitaxial stack 40. The second p-type contact electrode 35p is in direct contact with the second epitaxial stack 30.

[0056] A first adhesion layer 61 and a first p-type contact electrode 25p are sequentially provided on the second epitaxial stack 30. The first p-type contact electrode 25p is in direct contact with the first epitaxial stack 20.

[0057] A first n-type contact electrode 21n is provided on the first epitaxial stack 20. The first n-type semiconductor layer 21 may have a structure in which a part of the upper surface is recessed, and the first n-type contact electrode 21n may be provided in the recessed part.

[0058] A single-layer or multi-layer insulating film is provided on the substrate 11 on which the first to third epitaxial stacks 20, 30, and 40 are laminated. In one embodiment of the present invention, a first insulating film 81 and a second insulating film 83 may be provided on part of the side and upper surface of the first to third epitaxial stacks 20, 30, and 40 to cover the laminate of the first to third epitaxial stacks 20, 30, and 40. The first and / or second insulating films 81 and 83 may be made of various organic / inorganic insulating materials, and the material and form are not limited. For example, the first and / or second insulating films 81 and 83 may be provided as a silicon oxide film, a silicon nitride film, Al2O3, or a distributed Bragg reflector (DBR). The first and / or second insulating films 81 and 83 may be black organic polymer films.

[0059] The pixel is provided with contact parts for connecting wiring parts to the first to third epitaxial stacks 20, 30, and 40. The contact parts include a first contact part 20C for supplying an emission signal to the first epitaxial stack 20, a second contact part 30C for supplying an emission signal to the second epitaxial stack 30, a third contact part 40C for supplying an emission signal to the third epitaxial stack 40, and a fourth contact part 50C for applying a common voltage to the first to third epitaxial stacks 20, 30, and 40. In one embodiment of the present invention, the first to fourth contact parts 20C, 30C, 40C, and 50C may be provided at various positions when viewed from above.

[0060] The first to fourth contact portions 20C, 30C, 40C, and 50C may include first to fourth pads 20pd, 30pd, 40pd, and 50pd, and first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp, respectively.

[0061] The first to fourth pads 20pd, 30pd, 40pd, and 50pd are separated and insulated from each other.

[0062] The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be provided in regions that are separated and insulated from one another and overlap with the first to third epitaxial stacks 20, 30, and 40, i.e., light emission regions. The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be formed over the edges of the first to third epitaxial stacks 20, 30, and 40, respectively, thereby covering the side surfaces of the active layers of the first to third epitaxial stacks 20, 30, and 40.

[0063] The first contact portion 20C includes a first pad 20pd and a first bump electrode 20bp that are electrically connected to each other. The first pad 20pd is provided on the first p-type contact electrode 25p of the first epitaxial stack 20, and is connected to the first p-type contact electrode 25p through a first contact hole 20CH provided in the first insulating film 81. At least a portion of the first bump electrode 20bp overlaps with the first pad 20pd. The first bump electrode 20bp is connected to the first pad 20pd through a first through hole 20ct in a region overlapping with the first pad 20pd, sandwiching the second insulating film 83 therebetween.

[0064] The second contact portion 30C includes a second pad 30pd and a second bump electrode 30bp that are electrically connected to each other. The second pad 30pd is provided on the second p-type contact electrode 35p and is connected to the second p-type contact electrode 35p through a second contact hole 30CH formed in the first insulating film 81. At least a portion of the second bump electrode 30bp overlaps with the second pad 30pd. The second bump electrode 30bp is connected to the second pad 30pd through a second through hole 30ct in a region overlapping with the second pad 30pd, sandwiching the second insulating film 83 therebetween.

[0065] The third contact portion 40C includes a third pad 40pd and a third bump electrode 40bp that are electrically connected to each other. The third pad 40pd is provided on the third p-type contact electrode 45p and is connected to the third p-type contact electrode 45p through a third contact hole 40CH formed in the first insulating film 81. At least a portion of the third bump electrode 40bp overlaps with the third pad 40pd. The third bump electrode 40bp is connected to the third pad 40pd through a third through hole 40ct in a region overlapping with the third pad 40pd, sandwiching the second insulating film 83 therebetween.

[0066] The fourth contact portion 50C includes a fourth pad 50pd and a fourth bump electrode 50bp electrically connected to each other. The fourth pad 50pd is connected to the first to third epitaxial stacks 20, 30, 40 through first to third sub-contact holes 50CHa, 50CHb, 50CHc provided on the first n-type contact electrode 21n, the second and third n-type semiconductor layers of the first to third epitaxial stacks 20, 30, 40, respectively. Here, the third epitaxial stack 40 has a third n-type semiconductor layer exposed by removing a part of the upper surface thereof, and the fourth pad 50pd is connected to the third n-type semiconductor layer of the third semiconductor layer.

[0067] More specifically, the fourth pad 50pd is connected to the first epitaxial stack 20 through a first sub-contact hole 50CHa provided on the first n-type contact electrode of the first epitaxial stack 20, is connected to the second epitaxial stack 30 through a second sub-contact hole 50CHb provided on the second n-type semiconductor layer of the second epitaxial stack 30, and is connected to the third epitaxial stack 40 through a third sub-contact hole 50CHc provided on the third n-type semiconductor layer of the third epitaxial stack 40. At least a portion of the fourth bump electrode 50bp overlaps with the fourth pad 50pd. The fourth bump electrode 50bp is connected to the fourth pad 50pd through a fourth through hole 50ct in a region overlapping with the fourth pad 50pd, sandwiching the second insulating film 83 therebetween.

[0068] In one embodiment of the present invention, although not shown, the substrate 11 may further include wiring parts (see FIG. 5) that are provided corresponding to the first to fourth contact parts 20C, 30C, 40C, and 50C and are electrically connected to the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp, respectively, and / or driving elements such as thin film transistors connected to the wiring parts. For example, the first to third epitaxial stacks 20, 30, and 40 may be connected to first to third light emission signal wirings that supply light emission signals to the first to third epitaxial stacks 20, 30, and 40 via the first to third bump electrodes 20bp, 30bp, and 40bp, respectively, and a common wiring that supplies a common voltage to the first to third epitaxial stacks 20, 30, and 40 via the fourth bump electrode 50bp. In this embodiment, the first to third light emission signal wirings may correspond to the first to third scan wirings, and the common wiring may correspond to the data wiring, respectively.

[0069] Figures 3a to 7b are views sequentially showing a method for manufacturing a light-emitting device according to one embodiment of the present invention, in which Figures 3a, 4a, 5a, 6a, and 7a are plan views, and Figures 3b, 4b, 5b, 6b, and 7b are cross-sectional views along line A-A' of Figures 3a, 4a, 5a, 6a, and 7a.

[0070] 3a and 3b, a light emitting structure is formed on a substrate 11. In the light emitting structure, the third epitaxial stack 40, the third p-type contact electrode 45p, the second adhesive layer 63, the second p-type contact electrode 35p, the second epitaxial stack 30, the first adhesive layer 61, the first p-type contact electrode 25p, the first epitaxial stack 20, and the first n-type contact electrode 21n may be sequentially grown through various processes such as chemical vapor deposition, metal organic chemical vapor deposition, molecular beam deposition, etc.

[0071] The light emitting structure may be patterned into various shapes in consideration of the overall wiring connection structure, etc. For example, the light emitting structure may be formed in a polygonal shape when viewed from above in consideration of the positions of the contact holes, through holes, and pads described above.

[0072] According to one embodiment, portions of the first to third epitaxial stacks 20, 30, 40 and the first to third p-type contact electrodes 25p, 35p, 45p may be etched through an etching process, thereby exposing upper surfaces at positions where the first to fourth contact holes 20CH, 30CH, 40CH, 50CH (see Figures 4a and 4b) will be formed.

[0073] 4a and 4b, a first insulating film 81 may be conformally formed on the vertically stacked light emitting structures. The first insulating film 81 may include an oxide, such as silicon oxide and / or silicon nitride.

[0074] The first insulating film 81 is partially removed by patterning, and as a result, the first to fourth contact holes 20CH, 30CH, 40CH, and 50CH are formed.

[0075] The first contact hole 20CH is disposed on the first p-type contact electrode 25p and exposes a portion of the first p-type contact electrode 25p. The second contact hole 30CH is disposed on the second epitaxial stack 30 and exposes a portion of the second p-type contact electrode 35p. The third contact hole 40CH is disposed on the third p-type contact electrode 45p and exposes a portion of the third p-type contact electrode 45p. The fourth contact hole 50CH includes first to third sub-contact holes 50CHa, 50CHb, and 50CHc, and the first to third sub-contact holes 50CHa, 50CHb, and 50CHc are respectively arranged on the first n-type contact electrode 21n, the second n-type semiconductor layer of the second epitaxial stack 30, and the third n-type semiconductor layer of the third epitaxial stack 40, and expose portions of the first n-type contact electrode 21n, the second n-type semiconductor layer of the second epitaxial stack 30, and the third n-type semiconductor layer of the third epitaxial stack 40.

[0076] 5a and 5b, the first to fourth pads 20pd, 30pd, 40pd, and 50pd are formed on the first insulating film 81 in which the first to fourth contact holes 20CH, 30CH, 40CH, and 50CH are formed. As a conductive film material for forming the first to fourth pads 20pd, 30pd, 40pd, and 50pd, various conductors including metals can be used, and for example, the first to fourth pads 20pd, 30pd, 40pd, and 50pd may be made of at least one of Ni, Ag, Au, Pt, Ti, Al, and Cr.

[0077] The first to fourth pads 20pd, 30pd, 40pd, and 50pd are formed to overlap the portions where the first to fourth contact holes 20CH, 30CH, 40CH, and 50CH are formed. Here, the fourth pad 50pd may be formed to overlap the portions where the first to third sub-contact holes 50CHa, 50CHb, and 50CHc are formed at the same time.

[0078] 6a and 6b, a second insulating film 83 may be conformally formed on the first insulating film 81. The second insulating film 83 may include an oxide, for example, silicon oxide and / or silicon nitride.

[0079] The second insulating film 83 is partially removed by patterning, and as a result, the first to fourth through holes 20ct, 30ct, 40ct, and 50ct are formed.

[0080] The first to fourth through holes 20ct, 30ct, 40ct, and 50ct are disposed on the first to fourth pads 20pd, 30pd, 40pd, and 50pd, respectively, and expose a portion of the first to fourth pads 20pd, 30pd, 40pd, and 50pd.

[0081] 7a and 7b, first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp are formed on the second insulating film 83 in which the first to fourth through holes 20ct, 30ct, 40ct, and 50ct are formed.

[0082] The first to fourth bump electrodes 20bp, 30bp, 40bp, 50bp are formed so as to overlap the portions in which the first to fourth through holes 20ct, 30ct, 40ct, 50ct are formed, respectively, and as a result, the first to fourth bump electrodes 20bp, 30bp, 40bp, 50bp are connected to the first to fourth pads 20pd, 30pd, 40pd, 50pd via the first to fourth through holes 20ct, 30ct, 40ct, 50ct, respectively.

[0083] The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may have areas larger than the corresponding first to fourth pads 20pd, 30pd, 40pd, and 50pd. Also, the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may at least partially overlap with light emission regions from which the first to third epitaxial stacks 20, 30, and 40 emit light when viewed from above.

[0084] The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be formed by a plating method using various metals. The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may further include a seed layer for forming a metal layer in a plating process. Various metals, for example, metals including Cu, Ni, Ti, etc., may be used for the seed layer, and the seed layer may be variously changed depending on the metal material to be plated.

[0085] When the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp are formed by a plating method, the upper surfaces of the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp can be formed flat. The light emitting structure has an upper step due to etching or the like for forming a contact structure for connection with external wiring, and when connecting with other elements, the step may make it difficult to electrically connect other elements and the light emitting structure when forming a general metal layer. However, when formed by a plating method, each electrode having a flat upper surface can be formed even on a light emitting structure made of an epitaxial layer with a large step. In addition, the plated first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may have a flat upper surface by themselves, but the upper surfaces of the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be additionally polished to increase the flatness.

[0086] The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp are not particularly limited as long as they are used as wiring materials in semiconductor devices, and may be made of metals and / or metal alloys such as SnAg, Sn, CuSn, CuN, CuAg, Sb, Ni, Zn, Mo, and Co. In one embodiment of the present invention, the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be made of only Sn, or may be made of Cu / Ni / Sn. When the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp are made of Cu / Ni / Sn, the internal diffusion of impurities into the light emitting structure can be minimized, and in particular, by using Cu as the material of each bump electrode, the penetration of Sn into the light emitting structure can be prevented.

[0087] The first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be formed using a plating method, and then the strength of the first to fourth bump electrodes 20bp, 30bp, 40bp, and 50bp may be increased through an additional heat treatment process, i.e., a reflow process.

[0088] In an embodiment of the present invention, the light emitting device having the above-described structure may be embodied as a package and mounted on another device, for example, a printed circuit board, to function as a light emitting device package, and various wirings may be additionally provided to facilitate mounting on another device.

[0089] 8a to 8e are views sequentially showing a method for manufacturing a light emitting device package. In Fig. 8a to 8e, for convenience of explanation, the first to third epitaxial stacks are simplified as a light emitting structure 10, and the first to fourth pads and the first to fourth bump electrodes are simplified as pads pd and bump electrodes bp. In particular, in the drawings, the light emitting structure 10 is simplified as having a flat upper surface, but the upper surface has a step and / or a slope.

[0090] In an embodiment of the present invention, a light emitting device package may be formed by mounting at least one light emitting device 110 on a printed circuit board 11p having wiring, etc. The light emitting device package may include a plurality of light emitting devices 110.

[0091] Referring to FIG. 8a, a printed circuit board 11p is prepared, and a number of light emitting devices 110 are disposed on the printed circuit board 11p.

[0092] The printed circuit board 11p is formed with wiring and electrodes for electrical connection between various elements, and at least one light emitting element 110 may be mounted on a surface of the printed circuit board 11p. The printed circuit board 11p may be provided in various forms depending on the arrangement of the wiring, and in this embodiment, for convenience of explanation, electrodes are provided on the front surface, rear surface, and between the front surface and rear surface of the substrate 11. However, the arrangement of the wiring of the printed circuit board 11p is not limited thereto. In one embodiment of the present invention, the printed circuit board 11p may be flexible or may not be flexible.

[0093] In one embodiment of the present invention, the printed circuit board 11p has a front and a back. Upper electrodes 11pa are provided on the front of the printed circuit board 11p, lower electrodes 11pc are provided on the back, and via electrodes 11pb are provided to connect the upper electrodes 11pa and the lower electrodes 11pc through the front and back of the printed circuit board 11p. The front of the printed circuit board 11p is the surface on which the light emitting elements 110 are mounted. In one embodiment of the present invention, the upper electrodes 11pa of the printed circuit board 11p are formed at positions corresponding to the bump electrodes bp of the light emitting elements 110 to be attached later.

[0094] Each of the wirings and / or electrodes on the printed circuit board 11p may be surface-treated with ENIG (Electroless Nickel Immersion Gold). For example, in one embodiment of the present invention, particularly each of the upper electrodes 11pa may be surface-treated with ENIG. When each of the wirings and / or electrodes on the printed circuit board 11p is ENIG-treated, a portion of the wirings and / or electrodes may melt at high temperature and easily be connected to each of the bump electrodes bp of each of the light emitting elements 110.

[0095] Each light emitting element 110 is attached on the carrier substrate 11c and disposed on the printed circuit board 11p. The carrier substrate 11c is for transferring each light emitting element 110, and has an adhesive layer 13 formed on one surface thereof, and each light emitting element 110 is attached to the carrier substrate 11c by the adhesive layer 13. The adhesive layer 13 may be a silicon-based polymer having strong heat resistance and allowing each light emitting element 110 to be attached and detached, and may be manufactured in the form of a tape or sheet and provided on the lower surface of the carrier substrate 11c. The adhesive layer 13 may have an adhesive strength sufficient to stably attach each light emitting element 110 to the carrier substrate 11c, and may have an adhesive strength sufficient to easily separate each light emitting element 110 when attached to the printed circuit board 11p. That is, the adhesive strength of the adhesive layer 13 to the light emitting element 110 may be smaller than the adhesive strength between each light emitting element 110 and the printed circuit board 11p.

[0096] Each light emitting device 110 may be attached to the lower part of the carrier substrate 11c in an inverted form in which the substrate 11 is located at the top and the light emitting structure 10 is located at the bottom. Here, the light emitting device 110 attached to the carrier substrate 11c has an inverted form in which the rear surface of the substrate 11 is attached to the adhesive layer 13 on the carrier substrate 11c, and the substrate 11 is located at the top and the light emitting structure 10 is located at the bottom. Each light emitting device 110 is disposed on the printed circuit board 11p at a distance from the others while attached to the carrier substrate 11c.

[0097] Referring to FIG. 8b, each light emitting element 110 is attached on the printed circuit board 11p, and the carrier substrate 11c and the adhesive layer 13 are removed. Each light emitting element 110 attached on the carrier substrate 11c may be pressed from the top to the bottom so that each bump electrode bp contacts each corresponding upper electrode 11pa of the printed circuit board 11p. The pressing step may be performed at a high temperature, and a part of each upper electrode 11pa on the printed circuit board 11p is melted and connected to each bump electrode bp of each light emitting element 110. Although the carrier substrate 11c is removed later, the adhesive layer 13 on the carrier substrate 11c has a weaker adhesive strength than that between each bump electrode bp of each light emitting element 110 and each upper electrode 11pa of the printed circuit board 11p, so that the carrier substrate 11c can be easily separated from each light emitting element 110.

[0098] As a result of each bump electrode bp being attached to each upper electrode 11pa of the printed circuit board 11p in this manner, the overall structure is arranged in the order of the printed circuit board 11p, each bump electrode bp, each pad pd, the light emitting structure 10, and the substrate 11 from bottom to top. Light from the light emitting structure 10 travels in a direction from the light emitting structure 10 toward the rear surface of the substrate 11 (upward in the drawing), and as a result, the direction toward the front surface of the printed circuit board 11p is the direction in which the light is emitted.

[0099] Referring to FIG. 8c, a molding layer 90 is formed on the printed circuit board 11p on which each light emitting element 110 is mounted. The molding layer 90 has a property of transmitting at least a part of light and reflecting, scattering, and / or absorbing a part of external light. The molding layer 90 covers at least a part of the light emitting element 110 and reflects, scatters, and / or absorbs a part of the external light in various directions, thereby preventing the external light from being reflected in a specific direction, particularly a direction visible to a user. In addition, the molding layer 90 covers at least a part of the light emitting element 110 and prevents the light emitting element 110 from being damaged by moisture and / or physical impact from the outside, thereby improving the reliability of the light emitting element 110.

[0100] The molding layer 90 is provided to reflect, scatter, and / or absorb a portion of external light in various directions, and in particular, the molding layer 90 may have a black color. However, other than the black color, the molding layer 90 may have a color other than black as long as it can reflect, scatter, and / or absorb a portion of external light in various directions to prevent reflection of the external light toward the user as much as possible.

[0101] In order to prevent reflection of external light in a specific direction, the molding layer 90 is formed to surround at least a portion of the light emitting element 110, and in particular to cover the rear surface of the substrate 11 in the light emitting element 110. In one embodiment of the present invention, the molding layer 90 is formed to cover the rear surface of the substrate 11, thereby preventing external light from being reflected by the rear surface of the substrate 11 and being visually recognized by the user. In order to prevent such reflection of external light in a specific direction, the molding layer 90 may reflect, scatter, or absorb about 50% or more of the external light in various directions. In one embodiment of the present invention, the molding layer 90 may reflect, scatter, or absorb about 80% or more of the external light.

[0102] The molding layer 90 may be formed to a thickness that allows it to have transparency so that light directed from the light emitting structure 10 toward the rear surface (i.e., the upper side) of the substrate 11 can be emitted to the maximum extent. For example, the molding layer 90 may be formed to a thickness that transmits 50% or more of the light from the light emitting structure when provided on the rear surface of the light emitting structure 10, and may be provided to a thickness that provides a height of 100 micrometers or less from the rear surface of the light emitting structure 10. Alternatively, the molding layer 90 may be provided so that the height of the molding layer 90 from the rear surface of the light emitting structure 10 is smaller than the thickness of the light emitting element.

[0103] The molding layer 90 can be formed not only on the rear side of the substrate 11 but also cover the side of the light emitting element 110, i.e., the side of the substrate 11 and the side of the light emitting structure 10. By the molding layer 90 also covering the side of the light emitting element 110, at least a part of the light emitted through the side of the light emitting element 110 can be absorbed by the molding layer 90. In this way, the molding layer 90 can prevent the light emitted from the light emitting structure 10 from being mixed with the light emitted from the adjacent light emitting structure 10.

[0104] In one embodiment of the present invention, the molding layer 90 may be made of an organic polymer that absorbs light. In one embodiment of the present invention, the molding layer 90 may further include an organic / inorganic filler therein in addition to the organic polymer, or may not further include an organic / inorganic filler. For example, when the molding layer 90 includes a filler, the filler may be an inorganic filler. Various inorganic fillers may be used, and for example, silica, alumina, etc. may be used.

[0105] Also, the molding layer 90 fills at least a portion between the light emitting structure 10 and the printed circuit board 11p. That is, the molding layer 90 can fill the empty space between the light emitting structure 10 and the printed circuit board 11p where each bump electrode bp is provided. By filling the space between the light emitting structure 10 and the printed circuit board 11p with the molding layer 90, heat generated from the light emitting structure 10 can be effectively dispersed. As a result, the heat dissipation characteristics of each light emitting element 110 are improved.

[0106] In an embodiment of the present invention, the molding layer 90 may be manufactured by various methods, such as a lamination method, a coating method, a chemical vapor deposition method, a printing method, a transfer molding method, etc. When manufacturing the molding layer 90, various thinning processes may be used, including an additional process for planarizing the surface of the molding layer 90. For example, in order to planarize the surface of the molding layer 90, squeegeeing may be performed or pressure flattening may be performed using a flat plate after coating and before the material of the molding layer 90 is hardened. In addition, polishing or lapping may be performed on the surface after the material of the molding layer 90 is hardened.

[0107] In one embodiment of the present invention, the molding layer 90 is formed by a transfer molding method, so that the molding layer 90 can have a flat upper surface. The transfer molding method may be performed through an extrusion molding method in which a certain number of packages on which light emitting devices are mounted are placed on a molding die, and then a liquefied resin in a solid state is pressed into the die to form the mold.

[0108] The lamination method for planarizing the surface of the molding layer 90 may be a vacuum lamination method performed in a vacuum. In this case, the molding layer 90 may be formed of an organic polymer sheet in a film form, and may be formed by placing the organic polymer sheet on the printed circuit board 11p on which the light emitting devices 110 are mounted, and then heating and pressing the organic polymer sheet in a vacuum atmosphere. The organic polymer sheet may have some fluidity at high temperature and high pressure, and may fill the areas between the light emitting devices 110 and the spaces between the light emitting devices 110 and the printed circuit board 11p due to this fluidity. The organic polymer sheet is then cured.

[0109] In one embodiment of the present invention, the molding layer 90 is formed by a vacuum lamination method, so that the molding layer 90 can have a flat upper surface. Conventionally, the molding layer 90 is formed by a process of applying an organic polymer material and then curing it, in which case, a difference in upper surface height occurs between a portion where the light emitting elements 110 are mounted and a region where the light emitting elements 110 are not mounted. The difference in upper surface height causes non-uniformity of the light emitted from each light emitting element 110. However, according to one embodiment of the present invention, the upper surface of the molding layer 90 is formed flat, thereby increasing the uniformity of light regardless of the position of each light emitting element 110.

[0110] In addition, since the molding layer 90 is provided to stably hold each light emitting device 110, it is possible to obtain an effect of increasing the rigidity of the light emitting device package. In particular, since the molding layer 90 can fill the space between the printed circuit board 11p and each light emitting device 110, it is possible to obtain an effect of increasing the adhesive strength between the printed circuit board 11p and each light emitting device 110. As a result, the rigidity of the entire light emitting device package is further increased.

[0111] Referring to FIG. 8d, the surface of the molding layer 90 is textured to form a fine uneven portion 91 on the surface exposed to the outside of the molding layer 90. The fine uneven portion 91 is for diffuse reflection, and is intended to further minimize the reflection of external light into the user's field of vision as a result of the external light being diffusely reflected by the fine uneven portion 91. When the light emitting device package is used in various applications such as lighting and display devices, the substrate 11 of the light emitting device is disposed in a position facing the user's line of sight, and it is therefore necessary to prevent light reflected by the substrate 11 as much as possible. Thus, by additionally forming the fine uneven portion 91 in addition to the molding layer 90 having light scattering, light reflecting, and light absorbing properties, glare to the user due to reflection of external light is further reduced.

[0112] In one embodiment of the present invention, the molding layer may further include a filler such as silica or alumina therein, and after texturing, each of the filler particles may be exposed on the surface of the molding layer. In this case, each of the filler particles may be randomly exposed on the surface, thereby further improving the scattering of external light.

[0113] There are various methods for forming the fine projections and recesses 91. In one embodiment of the present invention, the surface of the molding layer 90 can be etched using plasma.

[0114] 9a and 9b are SEM photographs showing the surfaces of the molding layer with and without plasma treatment, respectively.

[0115] 9A, it can be seen that after the plasma treatment, a large number of fillers are randomly exposed to the outside on the surface of the molding layer, and the large number of fillers are exposed to the outside surface with various sizes and frequencies, which can significantly increase the scattering effect of external light by the fillers.

[0116] In contrast, in Figure 9b, it can be seen that the number of fillers exposed on the surface is significantly smaller without plasma treatment than after plasma treatment, which confirms that fine irregularities can be easily formed on the surface of the molding layer by using plasma treatment.

[0117] Here, as a result of analyzing the components before and after the plasma treatment, no change in the components of the molding layer was observed, which shows that the fine unevenness can be formed without modifying the molding layer.

[0118] In one embodiment of the present invention, besides the plasma treatment, micro-sandblasting can be used to roughen the surface and form fine irregularities. When using micro-sandblasting, fine particles of several micrometers to several tens of micrometers are sprayed onto the surface of the molding layer at high pressure, and the surface of the molding layer is cleaned by ultrasonic cleaning or the like, and then dried, thereby forming fine irregularities on the surface of the molding layer. Alternatively, a method of dry polishing or wet etching the surface of the molding layer 90 may be used alone or in combination with the above-mentioned methods.

[0119] According to an embodiment of the present invention, a fine concave-convex portion can be formed on the surface of a molding layer by transferring a fine concave-convex pattern to the surface of a molding layer using an imprint mold having a fine concave-convex pattern formed thereon.

[0120] 10a to 10e are cross-sectional views sequentially illustrating a process of forming a fine concave-convex portion on the surface of a molding layer using an imprint mold.

[0121] 10a, first, a master mold MM is manufactured. The master mold MM has the same pattern (indicated by 91) as the fine projections and recesses to be transferred onto the surface of the molding layer, and is used to subsequently form an inverse pattern on the imprint mold IMP.

[0122] 10b, after applying an imprint mold IMP material onto the master mold MM and curing the imprint mold IMP, the imprint mold IMP is separated from the master mold MM, so that the reverse pattern (indicated by 91R) of the fine projections and recesses on the master mold MM is formed on the underside of the imprint mold IMP.

[0123] Referring to FIG. 10c, the imprint mold IMP on which the inverse pattern 91R is formed is placed on the molding layer 90, and then pressed from the top to the bottom.

[0124] Referring to FIG. 10d, the inverse pattern 91R of the imprint mold IMP is transferred to the upper surface of the molding layer 90 by pressing the imprint mold IMP, and after the transfer, the imprint mold IMP is separated from the molding layer 90.

[0125] Referring to FIG. 10e, a fine concave-convex portion 91 is formed on the upper surface of the molding layer 90 from which the imprint mold IMP has been removed.

[0126] According to the present embodiment, the shape of the fine concave-convex portion of the final molding layer is determined depending on the shape of the fine concave-convex pattern on the master mold. Thus, the fine concave-convex pattern of the master mold can be formed with different shapes, densities, etc., as required. As a result, the shape and density of the fine concave-convex portion of the molding layer can be controlled, and ultimately, the degree of scattering of external light by the fine concave-convex portion on the upper surface of the molding layer can be easily adjusted.

[0127] 8e again, after the molding layer 90 having fine concaves and convexes is formed, the printed circuit board 11p and each light emitting device 110 are cut to be included in the light emitting device package in an appropriate size, thereby forming a light emitting device package. At this time, the light emitting devices 110 may be cut to be included individually separated, or may be cut to have a large area to include a plurality of light emitting devices 110. The number and area of ​​each light emitting device 110 during cutting may be set to different shapes depending on the device in which each light emitting device 110 will be mounted later.

[0128] In the light emitting device package, the number of light emitting devices mounted on a printed circuit board constituting one light emitting device package may be changed in various ways. Fig. 11a is a plan view showing a light emitting device package according to an embodiment of the present invention, which is a top view showing four light emitting devices mounted in a matrix on one printed circuit board, and Fig. 11b is a rear view of the light emitting device package shown in Fig. 11a. Fig. 12 is a circuit diagram of the light emitting device package shown in Figs. 11a and 11b.

[0129] 11a, 11b, and 12, the light emitting device package 110D includes a printed circuit board 11p and four light emitting devices 110 mounted on the printed circuit board 11p in a 2X2 shape. However, the number and arrangement of the light emitting device packages 110D are not limited thereto, and may be arranged in various matrix shapes, for example, 1X1, 3X3, 4X4, etc. Each light emitting device 110 has a structure in which the first to third epitaxial stacks are vertically stacked as described above. Thus, the first to third epitaxial stacks correspond to light emitting diodes that generate light, respectively. For example, the first to third epitaxial stacks may correspond to a first light emitting diode that emits red light, a second light emitting diode that emits green light, and a third diode that emits blue light, respectively.

[0130] 12, the first to sixth scan lines SC1, SC2, SC3, SC4, SC5, SC6 and the first and second data lines DT1, DT2 are connected to the four light emitting elements to drive the four light emitting elements. If the four light emitting elements are the first to fourth light emitting elements 110p, 110q, 110r, 110s, the first light emitting element 110p is connected to the first to third scan lines SC1, SC2, SC3 and the first data line DT1, and the second light emitting element 110q is connected to the first to third scan lines SC1, SC2, SC3 and the second data line DT2. The third light emitting element 110r is connected to the fourth to sixth scan lines SC4, SC5, SC6 and the first data line DT1, and the fourth light emitting element 110s is connected to the fourth to sixth scan lines SC4, SC5, SC6 and the second data line DT2.

[0131] When a scan signal is supplied through the scan line, the three light emitting diodes included in each of the first to fourth light emitting elements 110p, 110q, 110r, and 110s selectively emit light in response to a data signal input through the data line. Each diode is connected between the scan line and the data line, and emits light with a luminance corresponding to the magnitude of the applied voltage when a voltage equal to or greater than a threshold voltage is applied between the p-type semiconductor layer and the n-type semiconductor layer. That is, the light emission of each light emitting diode can be controlled by adjusting the voltage of the scan signal applied to the scan line and / or the data signal applied to the data line. For example, during each frame period, each light emitting diode emits light with a luminance corresponding to the input data signal. Each light emitting diode that receives a data signal corresponding to black luminance displays black by not emitting light during the corresponding frame period.

[0132] In an embodiment of the present invention, six scan lines and two data lines are provided, so that the first to fourth light emitting elements 110p, 110q, 110r, and 110s can be driven individually.

[0133] For this purpose, each light emitting element is mounted at a corresponding position on the printed circuit board 11p. Referring again to Figures 11a and 11b, upper electrodes 11pa are provided on the front surface of the printed circuit board 11p at positions corresponding to each light emitting element 110. That is, one light emitting element 110 has four bump electrodes bp, and four upper electrodes 11pa are provided for one light emitting element 110 on the printed circuit board 11p. The four bump electrodes bp of each light emitting element 110 are connected to the four upper electrodes 11pa while overlapping them in a one-to-one relationship.

[0134] In an embodiment of the present invention, the first to third bump electrodes of the first to fourth bump electrodes of the first light emitting element 110 are connected to the first to third scan lines, respectively, and the fourth bump electrode is connected to the first data line. The first to third bump electrodes of the first to fourth bump electrodes of the second light emitting element 110 are connected to the first to third scan lines, respectively, and the fourth bump electrode is connected to the second data line. The first to third bump electrodes of the first to fourth bump electrodes of the third light emitting element 110 are connected to the fourth to sixth scan lines, respectively, and the fourth bump electrode is connected to the first data line. The first to third bump electrodes of the first to fourth bump electrodes of the fourth light emitting element 110 are connected to the fourth to sixth scan lines, respectively, and the fourth bump electrode is connected to the second data line.

[0135] A total of eight bottom electrodes are arranged on the rear surface of the printed circuit board 11p. The eight bottom electrodes correspond to the first to sixth scan pads that supply scan signals to the first to sixth scan lines and the first and second data pads that supply data signals to the first and second data lines. For example, if the eight bottom electrodes formed on the rear surface of the printed circuit board 11p are the first to eighth bottom electrodes 11pc_1, 11pc_2, ..., 11pc_8, the first to sixth bottom electrodes 11pc_1, 11pc_2, ..., 11pc_6 correspond to the first to sixth scan pads, and the seventh and eighth bottom electrodes 11pc_7, 11pc_8 correspond to the first and second data pads. However, the first to sixth scan pads and the first and second data pads are not limited in their arrangement and order, and may be arranged in various shapes and areas on the rear surface of the printed circuit board 11p, and may be arranged in a different order.

[0136] In an embodiment of the present invention, a distance between two adjacent lower electrodes may be greater than a distance between two adjacent upper electrodes. In forming a light emitting device package, each lower electrode of the printed circuit board may function as a connection electrode for electrical connection with another electronic device when the light emitting device package is mounted on another electronic device, so that the light emitting device package may be more easily mounted on another electronic device by forming a relatively wide interval between two adjacent lower electrodes.

[0137] As described above, the light emitting device package according to an embodiment of the present invention uses a printed circuit board with a simple structure, and each light emitting device that can be driven individually can be easily mounted on the printed circuit board. In addition, since only eight input terminals (i.e., eight lower electrodes) are required to drive four light emitting devices, a large number of light emitting devices can be driven with a simple structure.

[0138] According to an embodiment of the present invention, the light emitting device package can be applied to other devices in various forms, such as using a single element as a light source, or mounting a plurality of light emitting device packages on a base substrate to form a module and using the module as a light source, etc. Devices using the light emitting device package include display devices, lighting devices for daily life, lighting for vehicles (headlights, luminaires, taillights, etc. for vehicles), various decorative lighting devices, etc.

[0139] FIG. 13 is a schematic cross-sectional view showing a light source module manufactured by mounting a number of light emitting device packages 110D on a base substrate 110b for application to a display device, a vehicle lighting device, or the like.

[0140] 13, a base substrate 110b on which each wiring is formed is prepared, and a number of light emitting device packages 110D can be mounted on the base substrate 110b. The base substrate 110b may or may not be flexible.

[0141] Each wiring on the base substrate 110b is provided to correspond to each lower electrode of each light-emitting element package 110D. Each wiring on the base substrate 110b may be connected to each lower electrode of the light-emitting element package via each connection electrode 11s. In one embodiment of the present invention, each connection electrode 11s may be provided in the form of solder.

[0142] When the light emitting device packages are mounted on the base substrate as shown in FIG. 13, if any one of the light emitting device packages is defective, it can be easily repaired by replacing only that light emitting device package with a non-defective one.

[0143] FIG. 14 is a plan view conceptually showing a case where a light emitting device package according to an embodiment of the present invention is applied to a display device, and FIG. 15 is a plan view showing an enlarged view of a portion P1 of FIG.

[0144] 14 and 15, the light emitting device according to an embodiment of the present invention may be used as a pixel in a display device capable of expressing various colors. A plurality of light emitting devices may be mounted on a base substrate in the form of each of the light emitting device packages 110D described above.

[0145] The display device 100 according to an embodiment of the present invention displays any visual information, such as text, video, photos, two-dimensional or three-dimensional images, and the like.

[0146] The display device 100 may be provided in various shapes, such as a closed polygon having straight sides, such as a rectangle, a circle having curved sides, such as an ellipse, a semicircle having straight and curved sides, a semi-ellipse, etc. In one embodiment of the present invention, the display device is provided in a rectangular shape.

[0147] The display device 100 has a plurality of pixels for displaying an image. Each pixel is the minimum unit for displaying an image and may be embodied as one light-emitting element. Accordingly, in this embodiment, each pixel is represented by 110. Each pixel 110 includes a light-emitting element having the above-described structure and can emit white light and / or colored light.

[0148] In one embodiment of the present invention, each pixel includes a first pixel 110 that emits red light. R , the second pixel 110 that emits green light; G , and a third pixel 110 that emits blue light. B The first to third pixels 110 R , 110 G , 110 B may correspond to the first to third epitaxial stacks of the light-emitting device described above, respectively.

[0149] First to third pixels 110 R , 110 G , 110 BThe light emitted by each pixel is not limited to this, and at least two pixels may emit light of the same color, or may emit different light from each other, and may emit light of a color different from the colors mentioned above, such as yellow, magenta, cyan, etc.

[0150] The pixels 110 are arranged in a matrix. Here, the arrangement of the pixels 110 in a matrix does not mean that the pixels 110 are arranged exactly in a line along a row or column, but means that the pixels 110 are generally arranged along rows or columns, but the detailed positions may vary, such as being arranged in a zigzag pattern.

[0151] According to the present embodiment, lighting devices of various sizes can be easily manufactured simply by mounting a number of light emitting device packages on a base substrate. For example, a display device having a large area can be easily manufactured by using a number of light emitting device packages. In addition, when the base substrate or the printed circuit board is flexible, the display device can also be flexible, so that display devices of various types, for example, a rollable display device, a foldable display device, a curved display device, etc., can be easily manufactured.

[0152] The present invention has been described above with reference to preferred embodiments thereof. However, a person skilled in the art or having ordinary knowledge in the art will understand that the present invention can be modified and changed in various ways without departing from the spirit and technical scope of the present invention as set forth in the claims below.

[0153] Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

Claims

1. a printed circuit board having a front surface and a back surface; At least one light emitting element provided on the front surface and emitting light in a direction toward the front surface; a molding layer disposed on the printed circuit board and surrounding the light emitting device; The light-emitting element is a light emitting structure provided on the printed circuit board; A substrate provided on the light emitting structure; a plurality of bump electrodes provided between the light emitting structure and the printed circuit board; The molding layer covers an upper surface of the substrate, and a fine concave-convex portion is formed on a surface of the molding layer exposed to the outside.

2. The light emitting device package according to claim 1 , wherein the micro-irregular portion is manufactured by at least one of a plasma treatment, a micro-sandblasting treatment, a pattern transfer, a dry polishing treatment, and a wet etching treatment.

3. The light-emitting device package according to claim 2 , wherein the molding layer has a substantially flat upper surface.

4. The light emitting device package according to claim 3 , wherein the molding layer reflects, scatters, or absorbs a portion of external light.

5. The light emitting device package according to claim 4 , wherein the molding layer is filled at least partially between the light emitting structure and the printed circuit board.

6. The light emitting device package according to claim 5 , wherein the molding layer has an external light reflectance, an external light scattering rate, or an external light absorption rate of about 50% or more.

7. The light emitting device package according to claim 6 , wherein the molding layer has a black color.

8. 2. The light emitting device package of claim 1, wherein the printed circuit board includes upper electrodes provided on the front surface, lower electrodes provided on the rear surface, and via electrodes connecting the upper electrodes and the lower electrodes, and each of the bump electrodes is connected to a corresponding one of the upper electrodes.

9. The light emitting device package of claim 8 , wherein a distance between two adjacent ones of the lower electrodes is greater than a distance between two adjacent ones of the upper electrodes.

10. The light emitting device package according to claim 8 , wherein the light emitting device is provided in a plurality of pieces.

11. The light emitting device package according to claim 10, wherein each of the light emitting devices is provided in a number of four, and each light emitting structure of the light emitting device includes a plurality of epitaxial stacks sequentially stacked on the substrate, emitting light in different wavelength bands, and having light emitting regions overlapping each other.

12. The plurality of epitaxial stacks include: a first epitaxial stack that emits a first light; a second epitaxial stack provided on the first epitaxial stack and configured to emit a second light having a wavelength band different from that of the first light; The light emitting device package according to claim 1 , further comprising: a third epitaxial stack provided on the second epitaxial stack and configured to emit a third light having a wavelength band different from the first and second lights.

13. Each of the first to third epitaxial stacks comprises: A p-type semiconductor layer; An n-type semiconductor layer; The light emitting device package according to claim 12 , further comprising: an active layer provided between the p-type semiconductor layer and the n-type semiconductor layer.

14. Each of the bump electrodes is a first bump electrode connected to the p-type semiconductor layer of the first epitaxial stack; a second bump electrode connected to the p-type semiconductor layer of the second epitaxial stack; a third bump electrode connected to the p-type semiconductor layer of the third epitaxial stack; The light emitting device package according to claim 13 , further comprising: a fourth bump electrode connected to each of the n-type semiconductor layers of the first, second and third epitaxial stacks.

15. The light emitting devices include first to fourth light emitting devices, Each of the lower electrodes includes first through sixth scan pads and first and second data pads, the first light emitting element is connected to the first to third scan pads and the first data pad; the second light emitting element is connected to the first to third scan pads and the second data pad; the third light emitting element is connected to the fourth to sixth scan pads and the first data pad; The light emitting device package of claim 11 , wherein the fourth light emitting device is connected to the fourth to sixth scan pads and the second data pad.

16. The light emitting device package according to claim 15, wherein in each light emitting device, the bump electrodes include first to fourth bump electrodes, first to third scan signals are applied to the first to third bump electrodes, and a data signal is applied to the fourth bump electrode.

17. The light emitting device package according to claim 1 , wherein the molding layer is formed by a vacuum lamination method.

18. A base substrate; A display device comprising: at least one light-emitting device package according to claim 1 provided on the base substrate.

19. A base substrate; A lighting device comprising: at least one light-emitting device package according to claim 1 provided on the base substrate.

20. forming each light emitting device; disposing each of the light emitting devices on a printed circuit board; forming a molding layer on the printed circuit board by a vacuum lamination method to cover each of the light emitting devices; treating a surface of the molding layer exposed to the outside to form a fine uneven portion on the surface of the molding layer; and cutting the printed circuit board and the molding layer to form a light emitting device package. The molding layer covers an upper surface of the substrate and includes a material that reflects, scatters, or absorbs a portion of external light.

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