A Display device having a semiconductor light emitting device

Abstract

The present invention relates to a display device including a semiconductor light-emitting element according to an embodiment. A display device including a semiconductor light-emitting element according to an embodiment may include a wiring substrate, a semiconductor light-emitting element disposed on the wiring substrate, a diffusion layer disposed on the semiconductor light-emitting element and comprising a light-scattering material, and a first black layer structure disposed on the diffusion layer and having a transparent layer. The first black layer structure having the above-mentioned transparent layer may include one or more transparent layers between a plurality of black layers. The first black layer structure having the above-described transparent layer may include a first black layer, a first transparent layer disposed on the first black layer, and a second black layer disposed on the first transparent layer. The first black layer structure having the above-described transparent layer may include a second transparent layer disposed on the second black layer and a third black layer disposed on the second transparent layer.

Description

Technology Field

[0001] The embodiment relates to a display device including a semiconductor light-emitting element. Background Technology

[0002] Large-area display devices include liquid crystal displays (LCDs), OLED displays, and micro-LED displays.

[0003] A micro-LED display is a display that uses a micro-LED, which is a semiconductor light-emitting element having a diameter or cross-sectional area of ​​100 μm or less, as a display element.

[0004] Because micro-LED displays use micro-LEDs, which are semiconductor light-emitting devices, as display elements, they possess excellent performance in many characteristics such as contrast ratio, response speed, color reproduction rate, viewing angle, brightness, resolution, lifespan, luminous efficiency, and luminance.

[0005] In particular, micro-LED displays have the advantage of being able to freely adjust size and resolution by separating and combining screens in a modular manner, and are capable of implementing flexible displays. They are being applied not only to TVs but also to digital signage.

[0007] Digital signage is a display installed inside or outside a building using a Digital Information Display (DID), and is a device that provides images or videos containing advertisements or various information.

[0008] Types of digital signage include outdoor digital signage and indoor digital signage.

[0009] Outdoor digital signage refers to digital signage installed on building exterior walls, electronic display boards, etc., or installed outdoors for outdoor cinemas. Indoor digital signage refers to digital signage installed on the interior walls of large shopping malls or in the form of freestanding signboards.

[0010] Micro-sized semiconductor light-emitting diodes (LEDs) can be employed as display elements in digital signage.

[0012] Meanwhile, the spectral characteristics of display devices, such as digital signage, can be expressed in the CIE 1976 Lu'v' color coordinate system. In the CIE 1976 Lu'v' color coordinate system, L (Brightness) represents lightness, where an L value of 0 indicates black and an L value of 100 indicates white.

[0013] Additionally, u' indicates whether the color leans toward red or green; if the u' value is negative, the color leans toward green, and if the u' value is positive, the color leans toward red.

[0014] In addition, v' indicates whether it is skewed toward yellow or blue; if v' is negative, it is skewed toward blue, and if v' is positive, it is skewed toward yellow. The color viewing angle, which is the difference in color tone of white, can be expressed as △u'v' @±60˚.

[0016] In internal comparison technology, a light scattering material is used in the coating layer to improve the color difference of white in Micro LED displays, that is, to improve color viewing angle characteristics.

[0018] However, when light-scattering agents are added to digital signage to improve color viewing angle characteristics, a problem arises where the agents clump together, causing a whitening effect. This results in a reduction in the black impression of the digital signage. Here, 'black impression' refers to the value indicating how closely the black color can be reproduced to its true nature. Black impression can be expressed as the L (Brightness) value based on the color coordinate system, and a lower L value indicates superior black impression.

[0020] Meanwhile, according to the internal comparative technology, a black film layer is placed on the coating layer to enhance the blackness. However, since the black film layer of the internal technology has low adhesion itself, a separate adhesive layer such as OCA must be interposed between the coating layer and the black film layer, and the adhesive layer such as OCA has the problem of low optical transmittance.

[0021] Furthermore, according to the internal technology, a grinding process is performed after the liquid coating layer has cured, prior to forming a black film layer on the coating layer. However, since the grinding process can cause mechanical damage to the semiconductor light-emitting device, there is a limitation in that the coating layer cannot be ground below a predetermined thickness. Additionally, there is a constraint that a coating layer containing dispersed light scattering materials must be provided on the upper side of the semiconductor light-emitting device to a predetermined thickness to ensure a color viewing angle; consequently, there is a problem where the blackness is reduced due to the presence of this coating layer containing dispersed light scattering materials. The problem to be solved

[0022] One of the technical challenges of the embodiment is to solve the problem that while the diffusion layer in which the light scattering material is dispersed improves color viewing angle characteristics, it causes a whitening effect that reduces the blackness.

[0023] That is, the technical problem of the embodiment is to provide a coating layer structure of a display device that can maintain or improve blackness while improving color viewing angle characteristics.

[0024] The technical problems of the embodiments are not limited to those described in this section and include those that can be identified through the description of the invention. means of solving the problem

[0025] A display device including a semiconductor light-emitting element according to an embodiment may include a wiring substrate (150), a semiconductor light-emitting element (110) disposed on the wiring substrate (150), a diffusion layer (165) disposed on the semiconductor light-emitting element (110) and including a light-scattering material (160), and a first black layer structure (180) disposed on the diffusion layer (165) and having a transparent layer.

[0026] The first black layer structure (180) having the above-mentioned transparent layer may include one or more transparent layers between a plurality of black layers.

[0027] The first black layer structure (180) having the above transparent layer may include a first black layer (181a), a first transparent layer (182a) disposed on the first black layer (181a), and a second black layer (181b) disposed on the first transparent layer (182a).

[0028] The first black layer structure (180) having the above transparent layer may include a second transparent layer (182b) disposed on the second black layer (181b) and a third black layer (181c) disposed on the second transparent layer (182b).

[0029] The thickness (T2E) of the diffusion layer (165) above the semiconductor light-emitting element (110) may be thinner than the thickness of the semiconductor light-emitting element (110).

[0030] The first black layer structure (180) having the above transparent layer can be heat-press bonded on the diffusion layer (165) without an adhesive layer.

[0032] In addition, a method for manufacturing a display device including a semiconductor light-emitting element according to an embodiment may include the step of placing a semiconductor light-emitting element (110) on a wiring substrate (150), the step of heat-pressing a diffusion layer (165) including a light-scattering material (160) on the semiconductor light-emitting element (110) in a semi-cured state, the step of heat-pressing a first black layer structure (180) having a transparent layer on the diffusion layer (165) in a semi-cured state, and the step of performing a curing process on the diffusion layer (165) and the first black layer structure (180) having a transparent layer.

[0033] The above diffusion layer (165) can be thermally compressed and bonded in a semi-cured state without an adhesive layer on the wiring substrate on which the semiconductor light-emitting element is placed.

[0034] The liquid material of the diffusion layer can be gap-filled up to the bottom surface of the semiconductor light-emitting element (110) by the thermal compression process of the diffusion layer (165).

[0035] The first black layer structure (180) having the above transparent layer can be heat-press bonded on the diffusion layer (165) without an adhesive layer.

[0036] The first black layer structure (180) having the above-mentioned transparent layer may include one or more transparent layers between a plurality of black layers.

[0037] The first black layer structure (180) having the above transparent layer may include a first black layer (181a), a first transparent layer (182a) disposed on the first black layer (181a), and a second black layer (181b) disposed on the first transparent layer (182a).

[0038] The first black layer structure (180) having the above transparent layer may include a second transparent layer (182b) disposed on the second black layer (181b) and a third black layer (181c) disposed on the second transparent layer (182b).

[0039] The thickness (T2E) of the diffusion layer (165) above the semiconductor light-emitting element (110) may be thinner than the thickness of the semiconductor light-emitting element (110).

[0041] Additionally, a display device including a semiconductor light-emitting element according to an embodiment may include a wiring substrate (150), a semiconductor light-emitting element (110) disposed on the wiring substrate (150), a first diffusion layer (165) disposed on the semiconductor light-emitting element (110) and including a first light-scattering material (160a), and a second black layer structure (180B) disposed on the first diffusion layer (165) and having a transparent layer and a diffusion layer.

[0042] The above second black layer structure (180B) may include a first transparent layer (182a), a second diffusion layer (166) disposed on the first transparent layer (182a), a second transparent layer (182b) disposed on the second diffusion layer (166), and a black layer (181) disposed on the second transparent layer (182b).

[0043] The second diffusion layer (166) has a second light scattering material (160b) dispersed in a matrix, and the matrix may include at least one of an epoxy-based, acrylic-based, silicone-based, or urethane-based matrix.

[0044] The thickness from the upper side of the semiconductor light-emitting element (110) to the black layer (181) may be thinner than the thickness of the semiconductor light-emitting element (110).

[0045] The second black layer structure (180B) including the above transparent layer and diffusion layer can be heat-press bonded onto the first diffusion layer (165) in a semi-cured state without an adhesive layer.

[0047] Additionally, a display device including a semiconductor light-emitting element according to an embodiment may include a wiring substrate (150), a semiconductor light-emitting element (110) disposed on the wiring substrate (150), a transparent layer (182) disposed on the semiconductor light-emitting element (110), and a third black layer structure (180C) disposed on the transparent layer (182) and including a diffusion layer.

[0048] The above third black layer structure (180C) may include the first diffusion layer (165a) and the first black layer (181a) disposed on the first diffusion layer (165a).

[0049] The above third black layer structure (180C) may include a second diffusion layer (165b) disposed on the first black layer (181a) and a second black layer (181b) disposed on the second diffusion layer (165b).

[0050] The thickness from the upper side of the semiconductor light-emitting element (110) to the top of the third black layer structure (180C) may be less than or equal to the thickness of the semiconductor light-emitting element (110).

[0051] The third black layer structure (180C) including the above diffusion layer can be heat-press bonded onto the transparent layer (182) without an adhesive layer in a semi-cured state.

[0052] In the above third black layer structure (180C), the first thickness (Tb1) of the first black layer (181a) positioned on the lower side may be thicker than the second thickness (Tb2) of the second black layer (181b) positioned on the upper side.

[0053] The first thickness (Td1) of the first diffusion layer (165a) positioned on the lower side in the third black layer structure (180C) above may be thicker than the second thickness (Td2) of the second diffusion layer (165b) positioned on the upper side. Effects of the invention

[0054] A display device including a semiconductor light-emitting element including a black layer structure with a light diffusion function according to an embodiment can provide a coating layer structure of the display device that can maintain or enhance the blackness while improving color viewing angle characteristics.

[0055] For example, the first embodiment includes a first black layer structure (180) having a transparent layer, thereby allowing the second thickness (T2) of the diffusion layer (165) to be thin. In particular, the second-2 thickness (T2E) of the diffusion layer (165) above the semiconductor light-emitting element (110) can be thinner than the thickness of the semiconductor light-emitting element (110).

[0056] According to the first embodiment, the color viewing angle characteristics can be improved because refraction occurs at each interface of the layer and a scattering effect is exerted by the first black layer structure (180) having a transparent layer. In addition, by ensuring a thin second thickness (T2) of the diffusion layer (165), the distribution of the scattering material (160) is reduced, thereby providing a coating layer structure of a display device that can maintain or improve the blackness, thus providing a complex technical effect.

[0057] In addition, according to the first embodiment, a first black layer structure (180) having a transparent layer without a separate adhesive layer can be heat-press bonded onto a diffusion layer (165). Accordingly, since an adhesive layer such as OCA can be omitted, there is a technical effect of increasing frontal brightness as light transmittance improves.

[0059] In addition, according to the second embodiment, the color viewing angle characteristics can be improved because refraction occurs at each interface of the layer and a scattering effect is exerted by the second black layer structure (180B) including a transparent layer and a diffusion layer. Furthermore, by ensuring a thin third thickness (T3) of the coating layer from the wiring substrate (150) to the black layer (181), the distribution of the scattering material is reduced, thereby providing a coating layer structure of a display device that can maintain or improve the blackness.

[0060] In addition, according to the second embodiment, a second black layer structure (180B) including a transparent layer and a diffusion layer can be heat-press bonded onto the first diffusion layer (165) without a separate adhesive layer. Accordingly, since an adhesive layer such as OCA can be omitted, there is a technical effect of increasing frontal brightness as light transmittance improves.

[0062] In addition, according to the third embodiment, the color viewing angle characteristics can be improved because refraction occurs at each interface of the layer by the third black layer structure (180C) including a diffusion layer, thereby producing a scattering effect. Furthermore, there is a composite technical effect of providing a coating layer structure of a display device that can maintain or improve the blackness by ensuring a thin thickness of the coating layer from the wiring substrate (150) to the top of the third black layer structure (180C) and thereby reducing the distribution of scattering material.

[0063] In addition, according to the third embodiment, a third black layer structure (180C) including a diffusion layer can be heat-press bonded onto a transparent layer (182) in a semi-cured state without a separate adhesive layer. Accordingly, since an adhesive layer such as OCA can be omitted, there is a technical effect of increasing frontal brightness as light transmittance improves.

[0064] In addition, according to the third embodiment, when heat-pressed onto the semiconductor light-emitting element (110), the first thickness (Tb1) of the first black layer (181a) positioned on the lower side can be controlled to be thicker than the second thickness (Tb2) of the second black layer (181b) positioned on the upper side. Accordingly, there is a technical effect of minimizing the change in blackness around the semiconductor light-emitting element (110) due to the step difference caused by the semiconductor light-emitting element (110).

[0065] In addition, according to the third embodiment, when heat-pressed onto the semiconductor light-emitting element (110), the first thickness (Td1) of the first diffusion layer (165a) placed on the lower side can be controlled to be thicker than the second thickness (Td2) of the second diffusion layer (165b) placed on the upper side. Accordingly, there is a technical effect of ensuring uniform scattering properties by minimizing the change in distribution of the scattering material (160) around the semiconductor light-emitting element (110) due to the step difference caused by the semiconductor light-emitting element (110).

[0066] The technical effects of the embodiments are not limited to those described in this section and include those that can be understood through the description of the invention. Brief explanation of the drawing

[0067] FIG. 1 is an exemplary diagram of a display device (1000) including a semiconductor light-emitting element for a display pixel according to an embodiment. FIG. 2 is a perspective view of one of a plurality of display modules (200) included in a display device (1000) according to an embodiment. FIG. 3 is a plan view of one display panel (210) included in a display module (200) according to an embodiment. FIG. 4 is a cross-sectional view of a semiconductor light-emitting device package along the line B1-B1' in a display panel (210) according to the embodiment shown in FIG. 3. FIG. 5 is a cross-sectional view of a display device (210R) including a semiconductor light-emitting element according to internal comparison technology. FIG. 6 is a photograph of a coating layer (165) observed with an optical microscope in a display device (210R) of the comparative technology. FIG. 7 is a cross-sectional view of a display device (210A) according to a first embodiment. FIGS. 8a to 8c are cross-sectional views of the process of manufacturing a display device (210A) according to the first embodiment. FIG. 9 is a cross-sectional view of a display device (210B) according to a second embodiment. FIGS. 10a and FIGS. 10b are cross-sectional views of a display device (210C) according to a third embodiment. Specific details for implementing the invention

[0068] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. The suffixes 'module' and 'part' for components used in the following description are assigned or used interchangeably for the sake of ease of drafting the specification and do not inherently possess distinct meanings or roles. Furthermore, the attached drawings are intended to facilitate an easy understanding of the embodiments disclosed in this specification, and the technical concepts disclosed in this specification are not limited by the attached drawings. Additionally, when an element such as a layer, region, or substrate is referred to as existing 'on' another component, this includes existing directly on the other element or having other intermediate elements existing between them.

[0069] The display devices described in this specification may include digital signage, digital TV, mobile phones, smartphones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation systems, slate PCs, tablet PCs, ultrabooks, desktop computers, etc. However, the configurations according to the embodiments described in this specification may be applied to devices capable of display, even if they are new product forms developed in the future.

[0071] The coating layer structure of a display device according to the following embodiments and a display device including the same will be described.

[0073] (Example)

[0074] FIG. 1 is an exemplary diagram of a display device (1000) including a semiconductor light-emitting element for a display pixel according to an embodiment. The display device (1000) according to an embodiment may include a plurality of assembled display modules (200).

[0075] The display device (1000) of the embodiment can be applied to digital signage. For example, FIG. 1 is an example of indoor digital signage, but the display device (1000) of the embodiment can also be applied to outdoor digital signage.

[0076] Next, FIG. 2 is a perspective view of one of a plurality of display modules (200) included in a display device (1000) according to an embodiment.

[0077] The display module (200) illustrated in FIG. 2 can be mounted in each cabinet and assembled in a block manner to implement the display device (1000) of the embodiment.

[0078] The display module (200) of the embodiment may include a plurality of display panels (210) that output images, a module holder (220) on which the display panels (210) are placed, and a module cover (230) placed on the outside of the module holder (220).

[0079] The plurality of display panels (210) can be arranged in a grid shape on a module holder (220) to form a single display module (200), and individual display modules (200) can be assembled in a predetermined cabinet shape to implement a display device (1000) according to an embodiment. Display data can be transmitted to the assembled individual display modules (200) via wired or wireless means.

[0081] FIG. 3 is a plan view of one display panel (210) included in a display module (200) according to an embodiment.

[0082] Referring to FIG. 3, a display panel (210) according to an embodiment may include a semiconductor light-emitting element (110) for a display pixel that implements each pixel.

[0083] For example, the semiconductor light-emitting element (110) for a display pixel according to the embodiment may include a first semiconductor light-emitting element (110a), a second semiconductor light-emitting element (110b), and a third semiconductor light-emitting element (110c), but is not limited thereto.

[0084] Each of the first to third semiconductor light-emitting elements (110a, 110b, 110c) may be arranged repeatedly to form individual subpixels. For example, the first to third semiconductor light-emitting elements (110a, 110b, 110c) may each be a Red light-emitting element, a Green light-emitting element, and a Blue light-emitting element, but are not limited thereto.

[0085] The first to third semiconductor light-emitting elements (110a, 110b, 110c) may have a size in the micrometer (㎛) range. A micrometer (㎛) size may mean that the width of at least one surface of the light-emitting element has a size of several to several hundred ㎛.

[0087] Next, FIG. 4 is a cross-sectional view of a semiconductor light-emitting device package along the line B1-B1' in a display panel (210) according to the embodiment shown in FIG. 3.

[0088] Referring to FIG. 4, each of the first to third semiconductor light-emitting elements (110a, 110b, 110c) may be disposed on a wiring substrate (150). FIG. 4 is a cross-sectional view of a semiconductor light-emitting element package in which an adjacent first semiconductor light-emitting element (110a) is disposed on a wiring substrate (150).

[0089] For example, a first wire (151) and a second wire (152) may be placed on a wiring board (150). The first wire (151) may be a common wire that applies negative (-) power, and the second wire (152) may be a wire that applies positive (+) power, but is not limited thereto.

[0090] The first semiconductor light-emitting element (110a) may include a first-1 semiconductor light-emitting element (110a1) and a first-2 semiconductor light-emitting element (110a2) arranged adjacently.

[0091] Each of the above-mentioned first-1 semiconductor light-emitting element (110a1) and first-2 semiconductor light-emitting element (110a2) may be mounted on the first wiring (151) and the second wiring (152) in a flip-chip form, but is not limited thereto.

[0092] According to the embodiment, the first-1 semiconductor light-emitting element (110a1) and the first-2 semiconductor light-emitting element (110a2) mounted on the first wiring (151) and the second wiring (152) can be symmetrically arranged.

[0093] For example, according to an embodiment, a second wiring (152) that applies positive (+) power to adjacent subpixels and a first wiring (151) that applies negative (-) power can be arranged symmetrically with respect to each other.

[0094] In addition, the n-electrode and p-electrode of the first-1 semiconductor light-emitting element (110a1) and the n-electrode and p-electrode of the first-2 semiconductor light-emitting element (110a2) mounted on each of the first wiring (151) and second wiring (152) may also be symmetrically arranged, but are not limited thereto.

[0096] Next, FIG. 5 is a cross-sectional view of a display device (210R) including a semiconductor light-emitting element according to internal comparison technology.

[0097] Referring to FIG. 5, the comparative technology (210R) may include a wiring substrate (150), a semiconductor light-emitting element (110), a diffusion layer (165) including a light scattering material (160), and a black film layer (170). The semiconductor light-emitting element (110) may include first to third semiconductor light-emitting elements (110a, 110b, 110c) arranged in a flip-chip manner on the wiring substrate (150).

[0098] FIG. 6 is a photograph of the diffusion layer (165) in the display device (210R) of the comparative technology observed with an optical microscope. For example, FIG. 6 may be a photograph of the first region (WC) of the display device (210R) according to the comparative technology shown in FIG. 5, but is not limited thereto.

[0099] Referring to FIG. 6, when adding a light scattering material (160) to the diffusion layer (165) to improve color viewing angle characteristics, an aggregation region (R) in which the light scattering materials clump together occurs. When such light scattering materials clump together and an aggregation region (R) occurs, a whitening phenomenon occurs in which a part of the coating layer appears white, and there is a problem of reduced blackness.

[0101] Meanwhile, according to the comparative technology (210R), a black film layer (170) is placed on a diffusion layer (165) to enhance the blackness. The diffusion layer (165) of the comparative technology is formed by a curing process after liquid coating, and a grinding process is performed on the cured diffusion layer (165) to a first thickness (T1) for surface flattening before the black film layer (170) is formed on the diffusion layer (165).

[0102] However, since the mechanical stress of the grinding process on the diffusion layer (165) can damage the semiconductor light-emitting element (110), there is a limitation in that the coating layer cannot be ground to a thickness of less than the first-second thickness (T1R).

[0103] In addition, there is a constraint that a coating layer (160) in which a light scattering material (165) is dispersed on the upper side of a semiconductor light-emitting element (110) must remain with a first-second thickness (T1R) that is more than twice the height of the semiconductor light-emitting element in order to secure a color viewing angle. Accordingly, there is a problem that the blackness is reduced due to the presence of a diffusion layer (165) with a remaining first-second thickness (T1R) in which a light scattering material (160) is dispersed on the upper side of a semiconductor light-emitting element (110), and there is also a problem that the thickness of the display device is increased.

[0104] In addition, since the black film layer (170) of the comparative technology (210R) has low adhesiveness, a separate adhesive layer (172), such as OCA, must be interposed between the diffusion layer (165) and the black film layer (170). Accordingly, the adhesive layer (172), such as OCA, has low optical transmittance, which causes a problem of degrading optical properties. Furthermore, the adhesive layer (172) has high shrinkage expansion due to thermal changes, which causes a problem of reduced reliability of the coating layer structure.

[0106] Next, FIG. 7 is a cross-sectional view of a display device (210A) according to a first embodiment.

[0107] Referring to FIG. 7, a display device (210A) according to a first embodiment may include a wiring substrate (150), a semiconductor light-emitting element (110), a diffusion layer (165) including a light-scattering material (160), and a first black layer structure (180) having a transparent layer. A first wiring (151) and a second wiring (152) may be formed on the wiring substrate (150), and a bump (125) may be formed on the semiconductor light-emitting element (110), but is not limited thereto.

[0108] The above diffusion layer (165) may have a light scattering material (160) dispersed in a matrix, and the matrix may include optical coating materials such as epoxy-based, acrylic-based, silicone-based, and urethane-based materials, but is not limited thereto.

[0109] The light scattering material (160) can improve light efficiency by scattering light emitted from a semiconductor light-emitting device (110). The light scattering material (160) may have a size in the nanometer (nm) range. The light scattering material (160) may include at least one of Zr, Si, Ti, Zn, BaS, and their oxides. Additionally, the light scattering material (160) may have a content of 0.01% to 30% relative to the matrix.

[0110] The surface of the light scattering material (160) may be hydrophobized. Through surface treatment, a silylation reaction may occur in the light scattering material (160), and the surface may become hydrophobic. As the surface of the light scattering material (160) becomes hydrophobic, the light scattering materials do not clump together, and dispersibility within the coating layer may be improved. Accordingly, the embodiment has the technical effect of improving light uniformity according to region as the light scattering material (160) is uniformly distributed within the diffusion layer (165).

[0112] Meanwhile, a black layer is employed in comparative technology to improve blackness. However, in comparative technology, there have been no attempts to consider light scattering using a black layer in addition to a scattering agent.

[0113] On the other hand, the first black layer structure (180) having a transparent layer in the first embodiment may include at least one transparent layer between a plurality of black layers.

[0114] For example, a first black layer structure (180) having a transparent layer may include a first black layer (181a), a first transparent layer (182a) disposed on the first black layer (181a), and a second black layer (181b) disposed on the first transparent layer (182a). Additionally, the first black layer structure (180) having a transparent layer may include a second transparent layer (182b) disposed on the second black layer (181b) and a third black layer (181c) disposed on the second transparent layer (182b).

[0115] In the example, the first to third black layers (181a, 181b, 181c) may include a pigment or dye capable of producing a black color in the matrix. For example, the first to third black layers (181a, 181b, 181c) may include carbon black, acetylene black, etc., but are not limited thereto.

[0116] In the examples, the matrix of the first to third black layers (181a, 181b, 181c) may include polymer materials such as epoxy, acrylic, silicone, and urethane, but is not limited thereto.

[0118] The first black layer structure (180) having a transparent layer of the first embodiment may include a transparent layer between a plurality of black layers, and through this, since refraction occurs at the interface of materials having different refractive indices, refraction occurs at each interface of the layer and can produce a scattering effect.

[0119] Accordingly, the first embodiment can secure a second thickness (T2) of the diffusion layer (165) thin, and in particular, can secure a second-2 thickness (T2E) of the diffusion layer (165) on the upper side of the semiconductor light-emitting element (110) thinner than the thickness of the semiconductor light-emitting element (110).

[0121] Table 1 below shows the black level and color viewing angle data for the examples and comparative examples.

[0122] Black Color field of view (△u'v' @±60˚ Frontal luminance (nit) Examples 23.0 0.002 / 0.003 547 Comparative example 25.0 0.005 / 0.004 531

[0123] If the difference in black level on a display device is about 0.3 or more, it is a significant difference.

[0124] In the comparative example, the black level was 25.0, the color viewing angle was 0.005 / 0.004 at ±60˚, and the frontal luminance was 531 nit.

[0125] On the other hand, in the example, the black level was improved to 23.0, the color viewing angle was improved to 0.002 / 0.003 at ±60˚ respectively, and the frontal brightness was also improved to 547 nit.

[0127] According to the first embodiment, by the first black layer structure (180) having a transparent layer, refraction occurs at each interface of the layer and a scattering effect is exerted, thereby improving the color viewing angle characteristics. In addition, by ensuring a thin second thickness (T2) of the diffusion layer (165), the distribution of the scattering material (160) can be reduced, and accordingly, there is a complex technical effect in which the blackness in the embodiment can be improved by 2.0 to 23.0, which is higher than the blackness of the comparative example of 25.0.

[0128] In addition, according to the first embodiment, since the first black layer structure (180) having a transparent layer without a separate adhesive layer can be heat-pressed bonded onto the diffusion layer (165), the adhesive layer such as OCA can be omitted, so there is a technical effect of increasing front brightness as light transmittance improves.

[0130] FIGS. 8a to 8c are cross-sectional views of the process of a method for manufacturing a display device (210A) according to a first embodiment.

[0131] The display device (210A) according to the first embodiment may undergo a curing process after heat pressing in a semi-cured state instead of the curing method after liquid coating of the comparative technology.

[0133] In FIGS. 8a to 8c below, the first black layer structure (180) having a transparent layer laminated in a semi-cured state is described as undergoing a heat-pressing process of the diffusion layer (165) in one step, but the embodiments are not limited thereto. For example, in other embodiments, the first black layer (181a), the first transparent layer (182a), the second black layer (181b), the second transparent layer (182b), and the third black layer (181c) may each be sequentially heat-pressed in a semi-cured state on the diffusion layer (165).

[0135] Referring to FIG. 8a, a semiconductor light-emitting element (110) can be mounted on a wiring board (150).

[0136] After the diffusion layer (165) containing the light scattering material (160) is prepared in a semi-cured state, a first thermal compression process (P1) can be performed on a wiring substrate (150) on which a semiconductor light-emitting element (110) is mounted, while being heated to a first temperature (H1) and subjected to a first pressure.

[0137] The above diffusion layer (165) may have a light scattering material (160) dispersed in a matrix, and the matrix may include optical coating materials such as epoxy-based, acrylic-based, silicone-based, and urethane-based materials, but is not limited thereto.

[0138] The first temperature mentioned above may be a temperature range in which the diffusion layer (165) is melted, and the diffusion layer melted into a liquid state may be filled into the bottom surface and side surface of the semiconductor light-emitting element (110). In the embodiment, the liquid material of the diffusion layer is gap-filled up to the bottom surface of the semiconductor light-emitting element (110) by the thermal compression process of the diffusion layer (165), thereby ensuring that there are no voids on the bottom surface of the semiconductor light-emitting element (110) and improving reliability.

[0139] In the first embodiment, the second thickness (T2) of the diffusion layer (165) can be secured thinner than the comparative technology, and in particular, the second-2 thickness (T2E) of the diffusion layer (165) above the semiconductor light-emitting element (110) can be secured thinner than the thickness of the semiconductor light-emitting element (110).

[0140] According to the first embodiment, by ensuring a thin second thickness (T2) of the diffusion layer (165), the distribution of the scattering material (160) is reduced, thereby providing a technical effect of maintaining or enhancing the blackness.

[0142] Next, referring to FIG. 8b, after the heat pressing process of the diffusion layer (165), the first black layer structure (180) having a transparent layer laminated in a semi-cured state can be heated to a second temperature (H2) and the second heat pressing process (P2) can be carried out at a second pressure.

[0143] The first black layer structure (180) having the above-described transparent layer may include at least one transparent layer between a plurality of black layers. For example, the first black layer structure (180) having the above-described transparent layer may include a first black layer (181a), a first transparent layer (182a) disposed on the first black layer (181a), and a second black layer (181b) disposed on the first transparent layer (182a). Additionally, the first black layer structure (180) having the above-described transparent layer may include a second transparent layer (182b) disposed on the second black layer (181b) and a third black layer (181c) disposed on the second transparent layer (182b).

[0144] The matrix of the first to third black layers (181a, 181b, 181c) may include polymer materials such as epoxy, acrylic, silicone, and urethane, but is not limited thereto.

[0145] The first and second transparent layers (182a, 182b) may include polymer materials such as epoxy, acrylic, silicone, and urethane, but are not limited thereto.

[0146] The second temperature may be a temperature range in which the first to third black layers (181a, 181b, 181c) and the first to second transparent layers (182a, 182b) are melted, or a range thereof, and the first to third black layers (181a, 181b, 181c) and the first to second transparent layers (182a, 182b) in a liquid state or semi-cured state may undergo precise adhesion with the diffusion layer (165).

[0147] According to the first embodiment, since the first black layer structure (180) having a transparent layer without a separate adhesive layer can be heat-pressed bonded onto the diffusion layer (165), the adhesive layer such as OCA can be omitted, so there is a technical effect of increasing front brightness as light transmittance improves.

[0149] Next, referring to FIG. 8c, the first black layer structure (180) having a diffusion layer (165) in a semi-cured state and a transparent layer can be cured by heating to a third temperature (H3).

[0151] The first black layer structure (180) having a transparent layer of the first embodiment may include a transparent layer between a plurality of black layers, and through this, since refraction occurs at the interface of materials having different refractive indices, refraction occurs at each interface of the layer and can produce a scattering effect.

[0152] According to the first embodiment, there is a composite technical effect of providing a coating layer structure of a display device that can maintain or improve the blackness by reducing the distribution of scattering material (160) by securing a thin second thickness (T2) of the diffusion layer (165) while improving color viewing angle characteristics by refraction occurring at each interface of the first black layer structure (180) having a transparent layer.

[0154] Next, FIG. 9 is a cross-sectional view of a display device (210B) according to a second embodiment.

[0155] The second embodiment may adopt the technical features of the first embodiment.

[0156] For example, a display device (210B) according to a second embodiment may include a wiring substrate (150), a semiconductor light-emitting element (110), and a first diffusion layer (165) including a first light scattering material (160a).

[0157] The following description will focus on the main features of the second embodiment.

[0159] The second embodiment may include a second black layer structure (180B) comprising a transparent layer and a diffusion layer on the first diffusion layer (165).

[0160] For example, the second black layer structure (180B) may include a first transparent layer (182a), a second diffusion layer (166) disposed on the first transparent layer (182a), a second transparent layer (182b) disposed on the second diffusion layer (166), and a black layer (181) disposed on the second transparent layer (182b).

[0161] The second diffusion layer (166) may have a second light scattering material (160b) dispersed in a matrix, and the matrix may include optical coating materials such as epoxy, acrylic, silicone, and urethane, but is not limited thereto.

[0162] The above black layer (181) may include a pigment or dye capable of producing a black color in the matrix.

[0164] The second black layer structure (180B) including a transparent layer and a diffusion layer of the second embodiment may include a diffusion layer between a plurality of transparent layers, and through this, since refraction occurs at the interface of materials having different refractive indices, refraction occurs at each interface of the layer and can produce a scattering effect.

[0165] Accordingly, the second embodiment can secure a third thickness (T3) of the coating layer from the wiring substrate (150) to the black layer (181) thinly, and in particular, can secure a third-2 thickness (T3E) from the upper side of the semiconductor light-emitting element (110) to the black layer (181) thinner than the thickness of the semiconductor light-emitting element (110).

[0167] According to the second embodiment, there is a composite technical effect of providing a coating layer structure of a display device that can maintain or improve the blackness by reducing the distribution of scattering material by ensuring a thin third thickness (T3) of the coating layer from the wiring substrate (150) to the black layer (181), while improving color viewing angle characteristics by generating refraction at each interface of the layer through the second black layer structure (180B) including a transparent layer and a diffusion layer.

[0168] In addition, according to the second embodiment, since the second black layer structure (180B) including a transparent layer and a diffusion layer can be heat-pressed bonded onto the first diffusion layer (165) in a semi-cured state without a separate adhesive layer, an adhesive layer such as OCA can be omitted, thus providing a technical effect of increasing frontal brightness as light transmittance improves.

[0170] Next, FIGS. 10a and FIGS. 10b are cross-sectional views of a display device (210C) according to a third embodiment.

[0171] The third embodiment may adopt the technical features of the first embodiment or the second embodiment.

[0172] For example, a display device (210C) according to the third embodiment may include a wiring substrate (150) and a semiconductor light-emitting element (110).

[0173] The following description will focus on the main features of the third embodiment.

[0174] The third embodiment may include a third black layer structure (180C) comprising a diffusion layer on a transparent layer (182).

[0175] For example, the third black layer structure (180C) may include the first diffusion layer (165a) and the first black layer (181a) disposed on the first diffusion layer (165a). Additionally, the third black layer structure (180C) may include a second diffusion layer (165b) disposed on the first black layer (181a) and a second black layer (181b) disposed on the second diffusion layer (165b).

[0176] The above transparent layer (182) may include optical coating materials such as epoxy-based, acrylic-based, silicone-based, and urethane-based materials, but is not limited thereto.

[0177] The first and second diffusion layers (165a, 165b) may have a light scattering material (160) dispersed in a matrix, and the matrix may include optical coating materials such as epoxy, acrylic, silicone, and urethane, but is not limited thereto.

[0178] The first and second black layers (181a, 181b) may include a pigment or dye capable of producing a black color in the matrix, and the matrix may include an optical coating material such as an epoxy-based, acrylic-based, silicone-based, or urethane-based material, but is not limited thereto.

[0180] The third black layer structure (180C) including the diffusion layer of the third embodiment may include a diffusion layer between a plurality of black layers, and through this, since refraction occurs at the interface of materials having different refractive indices, refraction occurs at each interface of the layer, thereby enabling a higher scattering effect.

[0181] Accordingly, the third embodiment can ensure that the thickness of the coating layer from the wiring substrate (150) to the top of the third black layer structure (180C) is thin, and in particular, the thickness from the upper side of the semiconductor light-emitting element (110) to the top of the third black layer structure (180C) can be ensured to be thinner than the thickness of the semiconductor light-emitting element (110).

[0182] According to the third embodiment, there is a composite technical effect of providing a coating layer structure of a display device that can maintain or improve the blackness by reducing the distribution of scattering material by ensuring a thin thickness of the coating layer from the wiring substrate (150) to the top of the third black layer structure (180C), thereby improving color viewing angle characteristics by generating refraction at each interface of the layer and thus producing a scattering effect.

[0183] In addition, according to the third embodiment, since the third black layer structure (180C) including a diffusion layer can be heat-pressed bonded onto the transparent layer (182) in a semi-cured state without a separate adhesive layer, an adhesive layer such as OCA can be omitted, thus providing a technical effect of increasing frontal brightness as light transmittance improves.

[0184] In addition, according to the third embodiment, a transparent layer (182) that is melted into a liquid state can be filled into the bottom surface and side surface of the semiconductor light-emitting element (110). For example, the transparent layer (182) may include a lower transparent layer (182f) that is gap-filled between the bottom surface of the semiconductor light-emitting element (110) and the first and second wiring (151, 152). In the third embodiment, the liquid material of the transparent layer is gap-filled up to the bottom surface of the semiconductor light-emitting element (110) by a thermal compression process of the transparent layer (182), thereby ensuring that there are no voids on the bottom surface of the semiconductor light-emitting element (110) and improving reliability.

[0185] Also, referring to FIG. 10a, the first thickness (Tb1) of the first black layer (181a) positioned on the lower side in the third black layer structure (180C) may be thicker than the second thickness (Tb2) of the second black layer (181b) positioned on the upper side.

[0186] According to the third embodiment, when heat-pressed onto a semiconductor light-emitting element (110), the first thickness (Tb1) of the first black layer (181a) positioned on the lower side is controlled to be thicker than the second thickness (Tb2) of the second black layer (181b) positioned on the upper side, thereby providing a technical effect of minimizing the change in blackness around the semiconductor light-emitting element (110) due to the step difference caused by the semiconductor light-emitting element (110).

[0188] Also, referring to FIG. 10b, the first thickness (Td1) of the first diffusion layer (165a) positioned on the lower side in the third black layer structure (180C) may be thicker than the second thickness (Td2) of the second diffusion layer (165b) positioned on the upper side.

[0189] According to the third embodiment, when heat-pressed onto a semiconductor light-emitting element (110), the first thickness (Td1) of the first diffusion layer (165a) placed on the lower side is controlled to be thicker than the second thickness (Td2) of the second diffusion layer (165b) placed on the upper side, thereby minimizing the change in distribution of the scattering material (160) around the semiconductor light-emitting element (110) due to the step difference caused by the semiconductor light-emitting element (110), thereby providing a technical effect of securing uniform scattering properties.

[0191] A display device including a semiconductor light-emitting element according to an embodiment can provide a coating layer structure of a display device that can maintain or improve blackness while improving color viewing angle characteristics.

[0192] For example, the first embodiment can secure a second thickness (T2) of the diffusion layer (165) thin, and in particular, can secure a second-2 thickness (T2E) of the diffusion layer (165) on the upper side of the semiconductor light-emitting element (110) thinner than the thickness of the semiconductor light-emitting element (110).

[0193] According to the first embodiment, there is a composite technical effect of providing a coating layer structure of a display device that can maintain or improve the blackness by reducing the distribution of scattering material (160) by securing a thin second thickness (T2) of the diffusion layer (165) while improving color viewing angle characteristics by refraction occurring at each interface of the first black layer structure (180) having a transparent layer.

[0194] In addition, according to the first embodiment, since the first black layer structure (180) having a transparent layer without a separate adhesive layer can be heat-pressed bonded onto the diffusion layer (165), the adhesive layer such as OCA can be omitted, so there is a technical effect of increasing front brightness as light transmittance improves.

[0196] In addition, according to the second embodiment, there is a composite technical effect of providing a coating layer structure of a display device that can maintain or improve the blackness by reducing the distribution of scattering material by ensuring a thin third thickness (T3) of the coating layer from the wiring substrate (150) to the black layer (181), while improving color viewing angle characteristics by generating refraction at each interface of the layer through the second black layer structure (180B) including a transparent layer and a diffusion layer.

[0197] In addition, according to the second embodiment, since a second black layer structure (180B) including a transparent layer and a diffusion layer can be heat-pressed bonded onto the first diffusion layer (165) without a separate adhesive layer, an adhesive layer such as OCA can be omitted, thereby providing a technical effect of increasing frontal brightness as light transmittance improves.

[0199] In addition, according to the third embodiment, since refraction occurs at each interface of each layer by the third black layer structure (180C) including a diffusion layer and a scattering effect is exerted, the color viewing angle characteristics are improved, and at the same time, by ensuring a thin thickness of the coating layer from the wiring substrate (150) to the top of the third black layer structure (180C), the distribution of scattering material is reduced, thereby providing a coating layer structure of a display device that can maintain or improve the blackness, thus providing a complex technical effect.

[0200] In addition, according to the third embodiment, since the third black layer structure (180C) including a diffusion layer can be heat-pressed bonded onto the transparent layer (182) in a semi-cured state without a separate adhesive layer, an adhesive layer such as OCA can be omitted, thus providing a technical effect of increasing frontal brightness as light transmittance improves.

[0201] In addition, according to the third embodiment, when heat-pressed onto the semiconductor light-emitting element (110), the first thickness (Tb1) of the first black layer (181a) placed on the lower side is controlled to be thicker than the second thickness (Tb2) of the second black layer (181b) placed on the upper side, thereby providing a technical effect of minimizing the change in blackness around the semiconductor light-emitting element (110) due to the step difference caused by the semiconductor light-emitting element (110).

[0202] In addition, according to the third embodiment, when heat-pressed onto a semiconductor light-emitting element (110), the first thickness (Td1) of the first diffusion layer (165a) placed on the lower side is controlled to be thicker than the second thickness (Td2) of the second diffusion layer (165b) placed on the upper side, thereby minimizing the change in distribution of the scattering material (160) around the semiconductor light-emitting element (110) due to the step difference caused by the semiconductor light-emitting element (110), thereby providing a technical effect of securing uniform scattering properties.

[0204] Although the present invention has been described above with reference to embodiments thereof, those skilled in the art will readily understand that various modifications and changes can be made to the present invention without departing from the spirit and scope of the invention as described in the following claims.

Claims

Claim 1 A display device comprising: a semiconductor light-emitting element; a wiring board; a semiconductor light-emitting element disposed on the wiring board; a diffusion layer disposed on the semiconductor light-emitting element and comprising a light-scattering material; and a first black layer structure disposed on the diffusion layer and having a transparent layer; wherein the first black layer structure having a transparent layer comprises a semiconductor light-emitting element having one or more transparent layers between a plurality of black layers, and wherein the plurality of black layers and the one or more transparent layers are stacked and disposed in a direction perpendicular to the diffusion layer. Claim 2 delete Claim 3 A display device comprising a semiconductor light-emitting element, wherein the first black layer structure having the transparent layer comprises: a first black layer; a first transparent layer disposed on the first black layer; and a second black layer disposed on the first transparent layer. Claim 4 A display device comprising a semiconductor light-emitting element, wherein, in paragraph 3, the first black layer structure having the transparent layer comprises: a second transparent layer disposed on the second black layer; and a third black layer disposed on the second transparent layer. Claim 5 A display device comprising a semiconductor light-emitting element, wherein, in claim 1, the thickness of the diffusion layer above the semiconductor light-emitting element is thinner than the thickness of the semiconductor light-emitting element. Claim 6 In claim 1, the first black layer structure having the transparent layer comprises a semiconductor light-emitting element that is heat-press bonded onto the diffusion layer without an adhesive layer, in a display device. Claim 7 A method for manufacturing a display device comprising: a semiconductor light-emitting element disposed on a wiring board; a diffusion layer provided with a light scattering material on the semiconductor light-emitting element and heat-pressed in a semi-cured state; a first black layer structure having a transparent layer on the diffusion layer and heat-pressed in a semi-cured state; and a step of performing a curing process on the first black layer structure having the diffusion layer and the transparent layer; wherein the first black layer structure having the transparent layer comprises one or more transparent layers between a plurality of black layers, and the plurality of black layers and the one or more transparent layers are stacked and arranged in a direction perpendicular to the diffusion layer. Claim 8 A method for manufacturing a display device including a semiconductor light-emitting element, wherein, in claim 7, the diffusion layer is thermally compressed and bonded in a semi-cured state without an adhesive layer on the wiring substrate on which the semiconductor light-emitting element is disposed. Claim 9 A method for manufacturing a display device including a semiconductor light-emitting element, wherein, in claim 7, the liquid material of the diffusion layer gap-fills up to the bottom surface of the semiconductor light-emitting element by a thermal compression process of the diffusion layer. Claim 10 In claim 7, a method for manufacturing a display device including a semiconductor light-emitting element, wherein the first black layer structure having the transparent layer is heat-press bonded on the diffusion layer without an adhesive layer. Claim 11 delete Claim 12 A method for manufacturing a display device comprising a semiconductor light-emitting element, wherein, in claim 7, the first black layer structure having the transparent layer comprises: a first black layer; a first transparent layer disposed on the first black layer; and a second black layer disposed on the first transparent layer. Claim 13 A method for manufacturing a display device comprising a semiconductor light-emitting element, wherein, in claim 12, the first black layer structure having the transparent layer comprises: a second transparent layer disposed on the second black layer; and a third black layer disposed on the second transparent layer. Claim 14 A method for manufacturing a display device including a semiconductor light-emitting element, wherein, in claim 7, the thickness of the diffusion layer above the semiconductor light-emitting element is thinner than the thickness of the semiconductor light-emitting element. Claim 15 A display device comprising a semiconductor light-emitting element, wherein the semiconductor light-emitting element comprises: a wiring board; a semiconductor light-emitting element disposed on the wiring board; a first diffusion layer disposed on the semiconductor light-emitting element and including a first light-scattering material; and a second black layer structure disposed on the first diffusion layer and having a transparent layer and a diffusion layer; wherein the second black layer structure comprises: a first transparent layer; a second diffusion layer disposed on the first transparent layer; a second transparent layer disposed on the second diffusion layer; and a black layer disposed on the second transparent layer; wherein the black layer is stacked and disposed in a direction perpendicular to the second diffusion layer. Claim 16 delete Claim 17 A display device comprising a semiconductor light-emitting element, wherein, in claim 15, the second diffusion layer has a second light-scattering material dispersed in a matrix, and the matrix comprises at least one of an epoxy-based, acrylic-based, silicone-based, and urethane-based matrix. Claim 18 A display device comprising a semiconductor light-emitting element according to claim 15, wherein the thickness from the upper side of the semiconductor light-emitting element to the black layer is thinner than the thickness of the semiconductor light-emitting element. Claim 19 In claim 15, the second black layer structure including the transparent layer and the diffusion layer is a display device including a semiconductor light-emitting element that is heat-press bonded onto the first diffusion layer in a semi-cured state without an adhesive layer. Claim 20 A display device comprising a semiconductor light-emitting element, wherein the semiconductor light-emitting element comprises: a wiring board; a semiconductor light-emitting element disposed on the wiring board; a transparent layer disposed on the semiconductor light-emitting element; and a third black layer structure disposed on the transparent layer and having a diffusion layer; wherein the transparent layer is filled on the bottom surface and side surface of the semiconductor light-emitting element, and the third black layer structure comprises: the diffusion layer having a first diffusion layer; a first black layer disposed on the first diffusion layer; a second diffusion layer disposed on the first black layer; and a second black layer disposed on the second diffusion layer. Claim 21 delete Claim 22 delete Claim 23 A display device comprising a semiconductor light-emitting element, wherein, in paragraph 20, the thickness from the upper side of the semiconductor light-emitting element to the top of the third black layer structure is less than or equal to the thickness of the semiconductor light-emitting element. Claim 24 A display device comprising a semiconductor light-emitting element, wherein, in claim 20, a third black layer structure including the above diffusion layer is heat-press bonded onto the above transparent layer without an adhesive layer in a semi-cured state. Claim 25 A display device comprising a semiconductor light-emitting element, wherein, in paragraph 20, the first thickness of the first black layer is thicker than the second thickness of the second black layer. Claim 26 A display device comprising a semiconductor light-emitting element, wherein, in claim 20, the first thickness of the first diffusion layer is thicker than the second thickness of the second diffusion layer.

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