Display device, method for manufacturing the same, and electronic device including a display device

Abstract

The present invention provides a display device, a method for manufacturing the same, and an electronic device including the display device. [Solution] The display device includes a backplane substrate containing at least one driving element, a first epitaxial structure, a second epitaxial structure, and a third epitaxial structure sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, a lens provided in the third epitaxial structure, and an anti-reflective layer between the third epitaxial structure and the lens.

Description

Technical Field

[0001] The present invention relates to a display device for displaying color images, a manufacturing method thereof, and an electronic device including the display device.

Background Art

[0002] As display devices, LCD (liquid crystal display) and OLED (organic light emitting diode) displays are widely used. Recently, technology for manufacturing high-resolution display devices using micro LEDs (micro light emitting diodes) has been attracting attention. Light emitting diodes (LEDs) have the advantages of low power consumption and environmental friendliness. Due to such advantages, industrial demand is increasing.

[0003] An LED display that directly uses such micro LEDs as pixels has been developed and is also being commercialized. LED display pixels are designed in various ways, and recently, various technologies for vertically stacking micro LEDs (R-LEDs) that emit red light, micro LEDs (G-LEDs) that emit green light, and micro LEDs (B-LEDs) that emit blue light have been introduced. However, so far, in a structure with vertically stacked micro LEDs, satisfactory results have not been obtained in terms of light efficiency and bonding.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The problem to be solved by the present invention is to provide a display device having an epitaxial type vertical stacking structure.

[0005] The problem that this invention aims to solve is to provide a method for manufacturing a display device having an epitaxial vertical stacking structure.

[0006] The problem that this invention aims to solve is to provide an electronic device including a display device having an epitaxial vertical stacking structure. [Means for solving the problem]

[0007] An exemplary embodiment of the present invention includes a backplane substrate including at least one drive element, a first epitaxial structure, a second epitaxial structure and a third epitaxial structure sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, a lens provided on the third epitaxial structure, and an anti-reflective layer between the third epitaxial structure and the lens, wherein each of the first epitaxial structure, the second epitaxial structure and the third epitaxial structure includes a first conductivity type semiconductor layer, an active layer and a second conductivity type semiconductor layer, the first epitaxial structure is configured to emit light of a first wavelength, the second epitaxial structure emits light of a second wavelength, and the third epitaxial structure emits light of a third wavelength, and the anti-reflective layer includes a material having a refractive index in the range of 1.7 to 2.1 and has a thickness in the range of 75 to 110 nm.

[0008] The first epitaxial structure can emit red wavelength light, the second epitaxial structure can emit green wavelength light, and the third epitaxial structure can emit blue wavelength light.

[0009] A reflective layer is further provided between the backplane substrate and the first epitaxial structure.

[0010] A first p-type electrode, a second p-type electrode, and a third p-type electrode are provided spaced apart between the backplane substrate and the first epitaxial structure, and an n-type electrode is provided between the third epitaxial structure and the anti-reflective layer.

[0011] The display device may include a plurality of pixels, each of which includes the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure, and the anti-reflective layer may have a structure in which the plurality of pixels are connected as a single body.

[0012] The display device may have a structure in which a plurality of pixels are included, each of the plurality of pixels is included in the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure, and the anti-reflective layer is provided individually for each of the plurality of pixels.

[0013] When the refractive index of the second conductive semiconductor layer of the third epitaxial structure is n1, the refractive index of the anti-reflective layer is n2, and the refractive index of the lens is n3, the condition n1>n2>n3 can be satisfied.

[0014] An exemplary embodiment of the present invention includes a backplane substrate containing at least one drive element, a first epitaxial structure, a second epitaxial structure and a third epitaxial structure sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, a lens provided on the third epitaxial structure, and a first anti-reflective layer and a second anti-reflective layer sequentially provided between the third epitaxial structure and the lens, starting from the third epitaxial structure. Each of the epitaxial structure and the third epitaxial structure includes a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein the first epitaxial structure is configured to emit light of a first wavelength, the second epitaxial structure is configured to emit light of a second wavelength, and the third epitaxial structure is configured to emit light of a third wavelength, wherein the first antireflection layer includes a first refractive index, the second antireflection layer includes a second refractive index smaller than the first refractive index, and the first and second antireflection layers have a thickness greater than 0 and 200 nm or less.

[0015] The first anti-reflective layer may have a refractive index of 1.9 or higher, and the second anti-reflective layer may have a refractive index of 1.9 or lower.

[0016] When the refractive index of the second conductive semiconductor layer of the third epitaxial structure is n1, the refractive index of the first anti-reflective layer is n21, the refractive index of the second anti-reflective layer is n22, and the refractive index of the lens is n3, the condition n1>n21>n22>n3 can be satisfied.

[0017] A method for manufacturing a display device according to an exemplary embodiment of the present invention includes the steps of forming a third epitaxial structure on a substrate, forming a second epitaxial structure on the third epitaxial structure, forming a first epitaxial structure on top of the second epitaxial structure to prepare a vertical stacked structure, forming a backplane substrate, facing the first epitaxial structure with respect to the backplane substrate to bond the backplane substrate and the vertical stacked structure, removing the substrate, forming an anti-reflective layer on the third epitaxial structure, and forming a lens on the anti-reflective layer, wherein the steps of forming the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure each include the steps of forming a first conductivity type semiconductor layer, forming an active layer, and forming a second conductivity type semiconductor layer, respectively, and the anti-reflective layer comprises a material having a refractive index in the range of 1.7 to 2.1 and has a thickness in the range of 75 to 110 nm.

[0018] An exemplary embodiment of the present invention includes an electronic device for forming an image, and a waveguide for guiding the image to a user's eye, wherein the display device includes a backplane substrate including at least one driving element, a first epitaxial structure, a second epitaxial structure, and a third epitaxial structure sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, a lens provided on the third epitaxial structure, and an anti-reflective layer between the third epitaxial structure and the lens, wherein each of the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure includes a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein the first epitaxial structure is configured to emit light of a first wavelength, the second epitaxial structure emits light of a second wavelength, and the third epitaxial structure emits light of a third wavelength, and the anti-reflective layer includes a material having a refractive index in the range of 1.7 to 2.1 and a thickness in the range of 75 to 110 nm. [Effects of the Invention]

[0019] Exemplary embodiments of the present invention can embody a display device that displays high-resolution color images using micro-light-emitting elements. The display device according to an exemplary embodiment of the present invention includes an epitaxial vertical stacked structure and an anti-reflective layer provided on top of the vertical stacked structure, which can increase the transmittance of each color light.

[0020] A method for manufacturing a display device according to an exemplary embodiment of the present invention allows for the formation of an epitaxial structure in a monolithic manner in the vertical direction, and the lamination of an anti-reflective layer on a vertically stacked structure. [Brief explanation of the drawing]

[0021] [Figure 1A] This drawing schematically shows a display device according to an exemplary embodiment of the present invention. [Figure 1B] This diagram shows an example of a display device further equipped with a reflective layer, as shown in Figure 1A. [Figure 2]The drawing shows an example in which an electrode structure is added to a display device according to an exemplary embodiment of the present invention. [Figure 3] The drawing shows an example in which an antireflection layer is provided in common for a plurality of pixels in a display device according to an exemplary embodiment of the present invention. [Figure 4] The drawing shows an example in which an antireflection layer is provided individually for each of a plurality of pixels in a display device according to an exemplary embodiment of the present invention. [Figure 5] The drawing shows an antireflection layer, a first layer provided on one surface of the antireflection layer, and a second layer provided on the other surface of the antireflection layer. [Figure 6] The drawing shows the result of simulating the transmittance of blue light (Blue) incident on the antireflection layer at an incident angle of 0 to 90°. [Figure 7] The drawing shows the result of simulating the transmittance of green light (Green) incident on the antireflection layer at an incident angle of 0 to 90°. [Figure 8] The drawing shows the result of simulating the transmittance of red light (Red) incident on the antireflection layer at an incident angle of 0 to 90°. [Figure 9] The drawing shows that the transmittance depending on the thickness has been simulated for an antireflection layer including an Al2O3 single layer. [Figure 10] The drawing shows that the transmittance depending on the thickness has been simulated for an antireflection layer including a single layer with a refractive index n = 1.9. [Figure 11] The drawing shows that the transmittance depending on the thickness has been simulated for an antireflection layer including a SiN single layer. [Figure 12] As a comparative example, the drawing shows that the transmittance depending on the thickness has been simulated for a SiO2 single layer. [Figure 13] As another comparative example, the drawing shows that the transmittance depending on the thickness has been simulated for a TiO2 single layer. [Figure 14]This drawing schematically shows an example of a display device according to an exemplary embodiment of the present invention, which includes two anti-reflective layers. [Figure 15] This diagram shows the results of a simulation of the blue light transmittance while changing the refractive index and thickness of the first and second anti-reflective layers. [Figure 16] This diagram shows the results of a simulation of the blue light transmittance while varying the thickness of the first anti-reflective layer containing SiN and the second anti-reflective layer containing Al2O3 within a range of 0 to 200 nm. [Figure 17] This diagram shows the results of a simulation of the transmittance of green light while varying the thickness of the first anti-reflective layer containing SiN and the second anti-reflective layer containing Al2O3 within a range of 0 to 200 nm. [Figure 18] This diagram shows the results of a simulation of the transmittance of red light while varying the thickness of the first anti-reflective layer containing SiN and the second anti-reflective layer containing Al2O3 within a range of 0 to 200 nm. [Figure 19] This diagram shows the simulated transmittance of blue light while varying the thickness of the first anti-reflective layer containing TiO2 and the second anti-reflective layer containing n=1.9 material within a range of 0 to 200 nm. [Figure 20] This diagram shows the simulated transmittance of green light while varying the thickness of the first anti-reflective layer containing TiO2 and the second anti-reflective layer containing n=1.9 material within a range of 0 to 200 nm. [Figure 21] This diagram shows the simulated transmittance of red light while varying the thickness of the first anti-reflective layer containing TiO2 and the second anti-reflective layer containing n=1.9 material within a range of 0 to 200 nm. [Figure 22] This diagram shows the simulated transmittance of blue light while varying the thickness of the first anti-reflective layer containing SiO2 and the second anti-reflective layer containing Al2O3 within a range of 0 to 200 nm. [Figure 23] This diagram shows the simulated transmittance of green light while varying the thickness of the first anti-reflective layer containing SiO2 and the second anti-reflective layer containing Al2O3 within a range of 0 to 200 nm. [Figure 24] This diagram shows the simulated transmittance of red light while varying the thickness of the first anti-reflective layer containing SiO2 and the second anti-reflective layer containing Al2O3 within a range of 0 to 200 nm. [Figure 25] These drawings illustrate a method for manufacturing a display device according to an exemplary embodiment of the present invention. [Figure 26] This is a schematic block diagram showing an electronic device according to an exemplary embodiment of the present invention. [Figure 27] This drawing shows an example of a micro-emitting display device according to an exemplary embodiment of the present invention being applied to a mobile device. [Figure 28] This drawing shows an example of a micro-emitting display device according to an exemplary embodiment of the present invention being applied to a vehicle display device. [Figure 29] This drawing shows an example of a microluminescent display device according to an exemplary embodiment of the present invention being applied to augmented reality glasses. [Figure 30] This drawing shows an example of a micro-emitting display device according to an exemplary embodiment of the present invention being applied to signage. [Figure 31] This drawing shows an example of a micro-luminescent display device according to an exemplary embodiment of the present invention being applied to a wearable display. [Modes for carrying out the invention]

[0022] The following description will detail various embodiments of display devices, their manufacturing methods, and electronic devices including display devices, with reference to the attached drawings. In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings is exaggerated for clarity and convenience of explanation. Terms such as "first," "second," etc., are used to describe various components, but components should not be limited by these terms. The terms are used solely for the purpose of distinguishing one component from another.

[0023] A singular expression includes multiple expressions unless the context clearly indicates otherwise. Furthermore, when a part "includes" a particular component, this means it includes other components, not excludes them, unless otherwise specified. Also, the size and thickness of each component in the drawings are exaggerated for clarity of explanation. When a given material layer is described as existing on a substrate or other layer, that material layer may be in direct contact with the substrate or other layer, or a third layer may exist between them. In the embodiments described below, the materials constituting each layer are illustrative, and other materials may be used.

[0024] Furthermore, terms such as "...part" and "module" as used in the specification refer to a unit that processes at least one function or operation, which may be embodied in hardware or software, or in a combination of hardware and software.

[0025] The specific embodiments described in this embodiment are illustrative and do not limit the technical scope in any way. For the sake of brevity of the specification, descriptions of conventional electronic configurations, control systems, software, and other functional aspects of the system may be omitted. Furthermore, the connections of lines or connecting members between components shown in the drawings are illustrative examples of functional and / or physical or circuit connections and may be substituted or shown as additional diverse functional, physical, or circuit connections in actual devices.

[0026] The use of the term "the aforementioned" and similar demonstrative terms can refer to both the singular and the plural.

[0027] The steps constituting the method shall be performed in any order unless otherwise explicitly stated. Furthermore, the use of all illustrative terms (e.g., etc.) is solely for the purpose of illustrating the technical idea and shall not limit the scope of rights unless otherwise specified in the claims.

[0028] Figure 1A is a schematic diagram showing a display device according to one embodiment.

[0029] The display device 100 includes a backplane substrate 110, a first epitaxial structure 120, a second epitaxial structure 130, and a third epitaxial structure 140, which are sequentially stacked from the backplane substrate 110 in a direction perpendicular to the backplane substrate 110, and a lens 160 provided on the third epitaxial structure 140. An anti-reflective layer 150 is provided between the third epitaxial structure 140 and the lens 160.

[0030] The backplane substrate 110 may include at least one drive element DD. The at least one drive element DD is for electrically driving the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140, and may include, for example, a transistor, a thin-film transistor, or a high electron mobility transistor (HEMT). However, the drive element DD is not limited to these and may further include a capacitor.

[0031] Each of the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140 may include a first conductivity type semiconductor layer 121, 131, 141, an active layer 122, 132, 142, and a second conductivity type semiconductor layer 123, 133, 143. The first epitaxial structure 120 may be configured to emit light of a first wavelength, the second epitaxial structure 130 may emit light of a second wavelength, and the third epitaxial structure 140 may be configured to emit light of a third wavelength. The first wavelength light, the second wavelength light, and the third wavelength light may have different wavelengths from each other.

[0032] For example, the first conductivity type semiconductor layers 121, 131, 141 may include a p-type semiconductor. Alternatively, the first conductivity type semiconductor layers 121, 131, 141 may include an n-type semiconductor. The first conductivity type semiconductor layers 121, 131, 141 may include a p-type semiconductor from the III-V series, such as p-GaN, p-InGaN, p-AlInGaN, or p-AlGaInP. The first conductivity type semiconductor layers 121, 131, 141 may have a single-layer or multilayer structure.

[0033] The active layers 122, 132, and 142 are provided on the upper surfaces of the corresponding first conductivity semiconductor layers 121, 131, and 141, respectively. The active layers 122, 132, and 142 can generate light through the bonding of electrons and holes. The active layer 122 of the first epitaxial structure 120 may contain a material that emits light of a first wavelength, for example, red wavelength light. The active layer 132 of the second epitaxial structure 130 may contain a material that emits light of a second wavelength, for example, green wavelength light. The active layer 142 of the third epitaxial structure 140 may contain a material that emits light of a third wavelength, for example, blue wavelength light. However, the active layers 122, 132, and 142 are not limited to these. The active layers 122, 132, and 142 may have a multi-quantum well (MQW) or single-quantum well (SQW) structure. The active layers 122, 132, and 142 may contain semiconductors from the Group III-V series, such as GaN, InGaN, AlInGaN, or AlGaInP. The active layers 122, 132, and 142 may contain, for example, an (InGaN / GaN) quantum well structure. The higher the indium (In) content in the active layers 122, 132, and 142, the longer the wavelength of light emitted from the active layers 122, 132, and 142.

[0034] The second conductivity semiconductor layers 123, 133, and 143 are provided on the upper surface of the corresponding active layers 122, 132, and 142, respectively. The second conductivity semiconductor layers 123, 133, and 143 may include, for example, an n-type semiconductor. Alternatively, the second conductivity semiconductor layers 123, 133, and 143 may include a p-type semiconductor. The second conductivity semiconductor layers 123, 133, and 143 may include an n-type semiconductor from the III-V series, such as n-GaN, n-InGaN, n-AlInGaN, or n-AlGaInP. The second conductivity semiconductor layers 123, 133, and 143 may have a single-layer or multilayer structure.

[0035] Light emitted from the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140 can be emitted upwards. The light emitted upwards can pass through the anti-reflective layer 150 and enter the lens 160.

[0036] The anti-reflective layer 150 may contain a substance that reduces or prevents reflection so that when light emitted from the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140 is emitted upward, the light is reflected downward, suppressing a decrease in the amount of light emitted. The display device 100 has a vertical stacked structure in which the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140 are stacked perpendicular to the backplane substrate 110. Therefore, the first wavelength light, second wavelength light, and third wavelength light, which have different wavelengths and are emitted from the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140, all pass through the anti-reflective layer 150. In other words, the anti-reflective layer 150 can reflect and transmit both the first wavelength light, the second wavelength light, and the third wavelength light. The anti-reflective layer 150 may have different reflectances or transmittances depending on the wavelength. Furthermore, the reflectance of the anti-reflective layer 150 may vary depending on its constituent material and thickness. Since the display device 100 according to an exemplary embodiment has a vertical stacked structure, the anti-reflective layer 150 needs to be designed to increase transmittance for each of the first, second, and third wavelengths of light. By adjusting the constituent material and thickness of the anti-reflective layer 150, the reflectance for the first, second, and third wavelengths of light can be reduced and the transmittance increased. The anti-reflective layer 150 may contain a material having a refractive index in the range of 1.7 to 2.1. The anti-reflective layer 150 may have a thickness in the range of 75 to 110 nm. When the anti-reflective layer 150 satisfies these conditions, the transmittance for the first, second, and third wavelengths of light may be 4% or more, each. The anti-reflective layer 150 may have transmittances of 5% or more, 6% or more, 15% or less, 13% or less, and 10% or less for the first, second, and third wavelengths of light, respectively. Here, transmittance represents the ratio of transmittance with the anti-reflective layer 150 to transmittance without the anti-reflective layer. Hereafter, transmittance in this specification may be used in this sense. The anti-reflective layer 150 may include, for example, Al2O3, SiN, TiO2, ZrO2, ZnO, Ta2O3, or SiON. The anti-reflective layer 150 can transmit light of multiple wavelengths with a common high transmittance.

[0037] The first wavelength light, second wavelength light, and third wavelength light that have passed through the anti-reflective layer 150 are incident on the lens 160 with high light emission efficiency and can be focused by the lens 160.

[0038] As described above, the display device 100 according to the exemplary embodiment has a vertical stacking structure, which allows for miniaturization of the area constituting a single pixel that emits light of multiple wavelengths. Furthermore, the display device 100 includes an anti-reflective layer 150, which enhances the light emission efficiency for each of the multiple wavelengths of light, enabling the display of color images with high optical efficiency and high resolution.

[0039] Figure 1B is a diagram showing an example in which the display device 100 shown in Figure 1A is further equipped with a reflective layer. In Figure 1B, the components having the same component numbers as those in Figure 1A perform substantially the same configuration and operation as those described in Figure 1A, so a detailed explanation is omitted here.

[0040] Referring to Figure 1B, the display device 100A may include a reflective layer 111 between the backplane substrate 110 and the first epitaxial structure 120. The reflective layer 111 may include, for example, Ag, Au, Al, Cr, or Ni, or alloys thereof. However, the reflective layer 115 is not limited to these. The reflective layer 111 can improve the light emission efficiency by reflecting the light emitted from the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140 downwards and emitting it again upwards to the display device 100A.

[0041] Figure 2 is a drawing showing a display device according to another exemplary embodiment.

[0042] Display device 100B is the display device 100 shown in Figure 1A with the addition of an electrode structure. In Figure 2, components using the same component numbers as in Figure 1A have substantially the same configuration and function as those in Figure 1A, so a detailed explanation is omitted here.

[0043] In the display device 100B, a first p-type electrode 115a, a second p-type electrode 115b, and a third p-type electrode 115c are provided spaced apart between the backplane substrate 110 and the first epitaxial structure 120. A pad 112 is provided between each of the first p-type electrode 115a, the second p-type electrode 115b, and the third p-type electrode 115c and the backplane substrate 110. The first p-type electrode 115a, the second p-type electrode 115b, and the third p-type electrode 115c contain at least one of Au, Cu, Ni, Ag, Cr, W, Al, Pt, Sn, Pb, Fe, Ti, and Mo, or may contain any one of ITO, ZrB, ZnO, InO, and SnO.

[0044] The first p-type electrode 115a can be electrically connected to the first conductivity type semiconductor layer 141 of the third epitaxial structure 140 by the first via electrode 117. The second p-type electrode 115b can be electrically connected to the first conductivity type semiconductor layer 131 of the second epitaxial structure 130 by the first via electrode 117. The third p-type electrode 115c can be directly connected to the first conductivity type semiconductor layer 121 of the first epitaxial structure 120.

[0045] An n-type electrode 145 is provided between the second conductivity type semiconductor layer 143 and the anti-reflective layer 150 of the third epitaxial structure 140. The n-type electrode may include a transparent electrode so that light is transmitted. The n-type electrode 145 may be electrically connected to the second conductivity type semiconductor layer 123 of the first epitaxial structure 120 and the second conductivity type semiconductor layer 133 of the second epitaxial structure 130 by a second via electrode 147. The second conductivity type semiconductor layer 143 of the third epitaxial structure 140 may be directly connected to the n-type electrode 145.

[0046] The display device 100B may further include a first insulating layer 118 provided so as to surround the side wall of the first via electrode 117 and a second insulating layer 148 provided so as to surround the side wall of the second via electrode 147. The first insulating layer 118 can insulate the first via electrode 117 from the first epitaxial structure 120 and the second epitaxial structure 130. The second insulating layer 148 can insulate the second via electrode 147 from the third epitaxial structure 140 and the second epitaxial structure 130. The first insulating layer 118 and the second insulating layer 148 may contain insulating material. The first insulating layer 118 and the second insulating layer 148 may contain, for example, SiO2, Si3N4, HfO2, or Al2O3.

[0047] The electrode structure described above is a so-called vertical electrode structure. However, the electrode structure of the display device according to the exemplary embodiment is not limited to this and may also have a horizontal electrode structure.

[0048] Figure 3 is a diagram showing a display device according to an exemplary embodiment that includes a plurality of pixels PX. The plurality of pixels PX may be arranged spaced apart from each other. Each of the plurality of pixels PX has the structure shown in Figure 1A, which is shown here in a simplified form for convenience. Each of the plurality of pixels PX may include the first epitaxial structure 120, the second epitaxial structure 130, and the third epitaxial structure 140 shown in Figure 1, and the anti-reflective layer 150 may have a structure in which it is connected to the plurality of pixels PX as a single body. In this way, the anti-reflective layer 150 can be formed as a single layer, and the manufacturing process can be simplified.

[0049] Figure 4 is a diagram showing an example in which the anti-reflective layer 150A is provided individually for each of the multiple pixels PX. In this way, the anti-reflective layer 150A is provided spaced apart for each of the multiple pixels PX.

[0050] Next, the effects and benefits of a display device according to an exemplary embodiment will be described.

[0051] Figure 5 is a schematic diagram showing an anti-reflective layer 220, a first layer 210 provided on one side of the anti-reflective layer 220, and a second layer 230 provided on the other side of the anti-reflective layer 220. The first layer 210 is also the second conductive semiconductor layer 143 of the third epitaxial structure 140 in the display device 100 shown in Figure 1A, for example, and the second layer 230 is also the lens 160. For such a three-layer structure, the light transmittance was simulated while changing the refractive index and thickness of the anti-reflective layer 220.

[0052] Figure 6 is a diagram showing the results of a simulation of the transmittance of blue light incident on the anti-reflective layer 220 at incident angles of 0 to 90°. In the graph in Figure 6, the horizontal axis represents the refractive index, and the vertical axis represents the thickness. The transmittance of blue light was simulated while varying the refractive index in the range of 1.4 to 2.4 and the thickness in the range of 0 to 200 nm. The color scale title on the right side of the graph shows the transmittance index, where the transmittance is the ratio of the transmittance with the anti-reflective layer to the transmittance without the anti-reflective layer. In other words, it shows the improvement in transmittance when the anti-reflective layer is provided. The higher the point, the higher the transmittance and the lower the reflectance. Referring to Figure 6, the area indicated by B shows the area with high transmittance of blue light, and the area indicated by XB shows the area with the maximum transmittance of blue light. In Figure 6, the area G shown by the dotted line shows the area with high transmittance of green light, which will be described later, and the area R shown by the dashed line shows the area with high transmittance of red light, which will be described later.

[0053] Figure 7 is a diagram showing the results of a simulation of the transmittance of green light incident on the anti-reflective layer 220 at incident angles of 0 to 90°. Referring to Figure 7, the area indicated by G represents the region with high transmittance of green light, and the area indicated by XG represents the region with the maximum transmittance of green light.

[0054] Figure 8 is a diagram showing the results of a simulation of the transmittance of red light incident on the anti-reflective layer 220 at incident angles of 0 to 90°. Referring to Figure 8, the area indicated by R represents the region with high transmittance of red light, and the area indicated by XR represents the region with maximum transmittance of red light.

[0055] By combining Figures 6, 7, and 8, regions with high transmittance for blue, green, and red light can be derived. For the sake of explanation, Figures 6, 7, and 8 show the B, G, and R regions with high transmittance together, and based on this, the anti-reflective layer 220 can have a refractive index in the range of 1.7 to 2.1. Furthermore, the thickness of the anti-reflective layer 220 can be in the range of 75 to 110 nm.

[0056] The external quantum efficiency (EQE) and internal quantum efficiency (IQE) of the active layers 122, 132, and 142 of the display device 100 decrease as the emission wavelength increases. Furthermore, the number of defects due to lattice mismatch increases as the indium content of the active layers 122, 132, and 142 increases. Therefore, the light efficiency of red light is relatively low among blue, green, and red light. Consequently, the thickness and refractive index of the anti-reflective layer 220 can be determined based on the region where the transmittance of red light is high among blue, green, and red light.

[0057] As described above, the anti-reflective layer 150 of the display device 100 according to the exemplary embodiment has a refractive index in the range of 1.7 to 2.1 and a thickness in the range of 75 to 110 nm, thereby having high transmittance for blue light, green light, and red light in common, and can be effectively applied in a vertical stacking structure in which a common area is used for each color light in a single pixel.

[0058] Figure 9 shows a simulation of the transmittance with thickness for an anti-reflective layer containing a single Al2O3 film. Here, transmittance is the ratio of transmittance with the anti-reflective layer to transmittance without the anti-reflective layer. The refractive index of Al2O3 is approximately 1.76. In the thickness range of 75 to 110 nm, the transmittance for blue light, green light, and red light improved by 4% to 8%, respectively.

[0059] Figure 10 shows a simulation of transmittance with increasing thickness for an anti-reflective layer containing a single film with a refractive index n=1.9. In the thickness range of 75 to 110 nm, the transmittance for blue light, green light, and red light improved by 6% to 9%, respectively.

[0060] Figure 11 shows a simulation of the transmittance with increasing thickness for an anti-reflective layer containing a single SiN film. The refractive index of SiN is approximately 2.1. In the thickness range of 75 to 110 nm, the transmittance for blue light, green light, and red light improved by 2% to 5%, respectively.

[0061] Figure 12 shows a simulation of transmittance with increasing thickness for a single SiO2 film as a comparative example. The refractive index of SiO2 is approximately 1.46. The simulation shows that a single SiO2 film has lower transmittance than the absence of a single SiO2 film, regardless of its thickness.

[0062] Figure 13 shows a simulation of transmittance with increasing thickness for a single TiO2 film as another comparative example. The refractive index of TiO2 is approximately 2.4. The single TiO2 film showed a very small improvement in transmittance for blue, green, and red light, less than 2%, in the range of 75 to 110 nm thickness.

[0063] On the other hand, referring to Figure 5, when the refractive index of the first layer 210 is n1, the refractive index of the anti-reflective layer 220 is n2, and the refractive index of the second layer 230 is n3, the condition n1>n2>n3 can be satisfied. In this way, when the layers adjacent to the anti-reflective layer 220 contain a material in which the refractive index decreases in the direction in which light is directed toward the lens 160, that is, in the direction in which light is emitted to the outside, the light transmittance increases. When the layer structure shown in Figure 5 is applied to Figure 1A, when the refractive index of the second conductive semiconductor layer 143 of the third epitaxial structure 140 is n1, the refractive index of the anti-reflective layer 150 is n2, and the refractive index of the lens 160 is n3, the condition n1>n2>n3 can be satisfied.

[0064] Next, Figure 14 is a schematic diagram showing an example of a display device according to an exemplary embodiment that includes two anti-reflective layers. In Figure 14, components using the same component numbers as in Figure 1A have substantially the same configuration and function, so a detailed explanation is omitted here.

[0065] The display device 200 may include a first anti-reflective layer 251 and a second anti-reflective layer 252 between the third epitaxial structure 140 and the lens 160. The first anti-reflective layer 251 and the second anti-reflective layer 252 may be arranged sequentially from the third epitaxial structure 140. The first anti-reflective layer 251 may include a first refractive index, and the second anti-reflective layer 252 may include a second refractive index smaller than the first refractive index. For example, the first anti-reflective layer 251 may include a refractive index of 1.9 or higher, and the second anti-reflective layer 252 may include a refractive index of 1.9 or lower. For example, the first anti-reflective layer 251 may include a refractive index of 1.9 or higher and 2.5 or lower, and the second anti-reflective layer 252 may include a refractive index of 1.4 or higher and 1.9 or lower. However, the refractive indices of the first anti-reflective layer 251 and the second anti-reflective layer 252 are not limited to these. The thickness d1 of the first anti-reflective layer 251 and the thickness d2 of the second anti-reflective layer 252 are both greater than 0 and may have a thickness of 200 nm or less.

[0066] On the other hand, when the refractive index of the second conductive semiconductor layer 143 of the third epitaxial structure 140 is n1, the refractive index of the first anti-reflective layer 251 is n21, the refractive index of the second anti-reflective layer 252 is n22, and the refractive index of the lens 160 is n3, the condition n1>n21>n22>n3 can be satisfied.

[0067] By adjusting the refractive index and thickness of the two-layer structure of the first anti-reflective layer 251 and the second anti-reflective layer 252, the light transmittance can be increased, thereby improving the light emission efficiency of the display device 200.

[0068] Figure 15 is a diagram showing the results of a simulation of the transmittance of blue light while changing the refractive index and thickness of the first anti-reflective layer 251 and the second anti-reflective layer 252. The horizontal axis represents the refractive index of the first anti-reflective layer 251, and the vertical axis represents the refractive index of the second anti-reflective layer 252. Instead of refractive index values, the names of the materials SiO2, Al2O3, SiN, and TiO2 are used. The refractive index of SiO2 is approximately 1.46, the refractive index of Al2O3 is approximately 1.76, the refractive index of SiN is approximately 2.1, and the refractive index of TiO2 is approximately 2.4. Figure 15 shows the maximum value numerically at the corresponding coordinates among the results of a simulation of the transmittance while changing the thickness of a two-layer anti-reflective layer composed of the materials corresponding to the horizontal and vertical axes. For example, in Figure 15, the A1 coordinate represents the maximum transmittance value of 9.5% in a simulation for the first anti-reflective layer 251 containing SiN and the second anti-reflective layer 252 containing Al2O3. Similarly, the A2 coordinate represents the maximum transmittance value of 8.9% in a simulation for the first anti-reflective layer 251 containing TiO2 and the second anti-reflective layer 252 containing a material with a refractive index n=1.9. In the graph, the size of the circles at each coordinate represents the relative transmittance values; that is, a larger circle indicates higher transmittance.

[0069] Figures 16, 17, and 18 are diagrams showing detailed simulation results for the A1 coordinate in Figure 15. Figure 16 shows simulations for blue light, Figure 17 for green light, and Figure 18 for red light, simulating transmittance while varying the thickness of the first anti-reflective layer 251 containing SiN and the second anti-reflective layer 252 containing Al2O3 in the range of 0 to 200 nm. The color scale titles indicate the transmittance index, with transmittances shown as C1 > C2 > C3. In Figures 16, 17, and 18, the numerical values ​​shown in the coordinates indicate the transmittance at the corresponding thickness structure. Referring to Figure 16, for example, when the first anti-reflective layer 251 containing SiN has a thickness of approximately 45 nm and the second anti-reflective layer 252 containing Al2O3 has a thickness of approximately 83 nm, the transmittance for blue light is 1.094. In other words, the transmittance appears to be approximately 9.4% higher compared to when there is no anti-reflective layer. Referring to Figure 17, when the first anti-reflective layer 251 containing SiN has a thickness of approximately 90 nm and the second anti-reflective layer 252 containing Al2O3 has a thickness of approximately 120 nm, the transmittance of green light is 1.093. Referring to Figure 18, for example, when the first anti-reflective layer 251 containing SiN has a thickness of approximately 90 nm and the second anti-reflective layer 252 containing Al2O3 has a thickness of approximately 120 nm, the transmittance of red light is 1.09. Referring to Figures 16, 17, and 18, the thickness of the first anti-reflective layer 251 containing SiN is smaller than the thickness of the second anti-reflective layer 252 containing Al2O3.

[0070] Figures 19, 20, and 21 are diagrams showing detailed simulation results for the A2 coordinate in Figure 15. Figure 19 shows simulations for blue light, Figure 20 for green light, and Figure 21 for red light, simulating transmittance while varying the thickness of the first anti-reflective layer 251 containing TiO2 and the second anti-reflective layer 252 containing n=1.9 material in the range of 0 to 200 nm. In Figures 19, 20, and 21, the numerical values ​​shown in the coordinates indicate the transmittance for the corresponding thickness structure. Referring to Figure 19, for example, when the first anti-reflective layer 251 containing TiO2 has a thickness of approximately 150 nm and the second anti-reflective layer 252 containing n=1.9 material has a thickness of approximately 89 nm, the transmittance for blue light is approximately 1.089. Referring to Figure 20, when the first anti-reflective layer 251 containing TiO2 has a thickness of approximately 60 nm and the second anti-reflective layer 252 containing a material with n=1.9 has a thickness of approximately 80 nm, the transmittance of green light is approximately 1.077. Referring to Figure 21, for example, when the first anti-reflective layer 251 containing TiO2 has a thickness of approximately 10 nm and the second anti-reflective layer 252 containing a material with n=1.9 has a thickness of approximately 120 nm, the transmittance of red light is approximately 1.076.

[0071] Figures 22, 23, and 24 show the transmittance simulations while varying the thickness of the first anti-reflective layer 251 containing SiO2 and the second anti-reflective layer 252 containing Al2O3 in the range of 0 to 200 nm. Figure 22 shows the transmittance simulation for blue light, Figure 23 for green light, and Figure 24 for red light. Referring to Figure 15, when the first anti-reflective layer 251 containing SiO2 and the second anti-reflective layer 252 containing Al2O3 are included, the maximum transmittance for blue light is 7.3%. Figure 22 shows the detailed simulation results for blue light, for example, when the first anti-reflective layer 251 containing SiO2 has a thickness of approximately 5 nm and the second anti-reflective layer 252 containing Al2O3 has a thickness of approximately 120 nm, the transmittance for blue light is approximately 1.0731. Figure 23 shows the detailed simulation results for green light. For example, when the first anti-reflective layer 251 containing SiO2 has a thickness of approximately 5 nm and the second anti-reflective layer 252 containing Al2O3 has a thickness of approximately 118 nm, the transmittance for green light is approximately 1.077. Figure 24 shows the detailed simulation results for red light. For example, when the first anti-reflective layer 251 containing SiO2 has a thickness of approximately 10 nm and the second anti-reflective layer 252 containing Al2O3 has a thickness of approximately 110 nm, the transmittance for red light is approximately 1.073. Referring to Figures 22, 23, and 24, the thickness of the first anti-reflective layer 251 containing SiO2 is smaller than the thickness of the second anti-reflective layer 252 containing Al2O3.

[0072] As described above, the display device 200 according to an exemplary embodiment includes two anti-reflective layers 251 and 252, which can increase the transmittance of each of the multiple color lights.

[0073] Next, Figure 25 is a drawing showing a method for manufacturing a display device according to an exemplary embodiment. The method for manufacturing a display device according to an exemplary embodiment may include the steps of forming a third epitaxial structure on a substrate (S10), forming a second epitaxial structure on the third epitaxial structure (S20), and forming a first epitaxial structure on top of the second epitaxial structure to prepare a vertically stacked structure (S30). The substrate is a growth substrate for growing epitaxial structures thereon, and the substrate may include, for example, silicon, sapphire, or GaAs. However, it is not limited to these, and the substrate may include materials other than these.

[0074] The third epitaxial structure can emit blue light, for example; the second epitaxial structure can emit green light; and the first epitaxial structure can emit red light. Here, the names of the first, second, and third epitaxial structures are used consistently with those of their corresponding components when comparing with Figure 1. When growing the third, second, and first epitaxial structures on a substrate, the third epitaxial structure, which is formed first on the substrate, has relatively more defects than the first epitaxial structure, which is formed later. Therefore, it is desirable that the first epitaxial structure, which emits red light with relatively lower light efficiency, be formed last.

[0075] Then, a backplane substrate is formed (S40). The backplane substrate may include at least one drive element. The vertical stacked structure is inverted so that the first epitaxial structure faces the backplane substrate, and the backplane substrate and the vertical stacked structure are bonded (S50). The vertical stacked structure may have a structure in which the first epitaxial structure, the second epitaxial structure and the third epitaxial structure are stacked vertically in order from the backplane substrate. As mentioned above, it is desirable that the first epitaxial structure that emits red light is formed last in the growth process, and as a result, the vertical stacked structure is inverted and bonded to the backplane substrate so that the first epitaxial structure can be located on top of the backplane substrate. In this way, after bonding the vertical stacked structure to the backplane substrate, the substrate can be removed (S60). Then, an anti-reflective layer can be formed on the third epitaxial structure (S70). A lens can be formed on the anti-reflective layer (S80).

[0076] This makes it possible to manufacture a display device that includes an anti-reflective layer. On the other hand, the step of forming the anti-reflective layer may include the step of forming a first anti-reflective layer and the step of forming a second anti-reflective layer.

[0077] The steps of forming the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure may include the steps of forming a first conductivity type semiconductor layer, forming an active layer, and forming a second conductivity type semiconductor layer, respectively.

[0078] As described above, the display device according to the exemplary embodiment may include an anti-reflective layer that commonly enhances the transmittance for blue, green, and red light. The anti-reflective layer may be configured by adjusting its thickness and refractive index to have an optimal transmittance for multiple colors of light. As a result, the display device having a vertical stacked structure can enhance the transmittance for blue, green, and red light, and improve light emission efficiency, without the need for color filters. A display device with improved light emission efficiency for multiple colors of light can be applied to a variety of electronic devices.

[0079] Figure 26 is a block diagram showing an electronic device including a display device according to an exemplary embodiment.

[0080] Referring to Figure 26, the electronic device 8201 is provided within the network environment 8200. In the network environment 8200, the electronic device 8201 can communicate with other electronic devices 8202 through a first network 8298 (such as a short-range wireless communication network), or with other electronic devices 8204 and / or a server 8208 through a second network 8299 (such as a long-range wireless communication network). The electronic device 8201 can communicate with electronic device 8204 through the server 8208. The electronic device 8201 may include a processor 8220, memory 8230, input device 8250, sound output device 8255, display device 8260, audio module 8270, sensor module 8276, interface 8277, haptic module 8279, camera module 8280, power management module 8288, battery 8289, communication module 8290, subscriber identification module 8296, and / or antenna module 8297. In the electronic device 8201, some of these components may be omitted, or other components may be added. Some of these components may be realized as a single integrated circuit. For example, the sensor module 8276 (fingerprint sensor, iris sensor, illuminance sensor, etc.) may be realized by being incorporated into the display device 8260 (display, etc.).

[0081] The processor 8220 can execute software (such as program 8240) to control one or more other components (hardware, software components, etc.) of the electronic devices 8201 connected to the processor 8220, and perform various data processing or calculations. As part of the data processing or calculations, the processor 8220 can load instructions and / or data received from other components (such as sensor module 8276, communication module 8290) into volatile memory 8232, process the instructions and / or data stored in volatile memory 8232, and store the resulting data in non-volatile memory 8234. Non-volatile memory 8234 may include internal memory 8236 and external memory 8238. The processor 8220 may include a main processor 8221 (central processing unit, application processor, etc.) and auxiliary processors 8223 (graphics processing unit, image signal processor, sensor hub processor, communication processor, etc.) that can operate independently or together with it. The auxiliary processors 8223 use less power than the main processor 8221 and can perform specialized functions.

[0082] The auxiliary processor 8223 can control functions and / or states related to some components of the electronic device 8201 (such as the display device 8260, sensor module 8276, and communication module 8290) on behalf of the main processor 8221 when the main processor 8221 is inactive (sleep state), or together with the main processor 8221 when the main processor 8221 is active (application execution state). The auxiliary processor 8223 (such as the image signal processor and communication processor) may be embodied as part of other functionally related components (such as the camera module 8280 and communication module 8290).

[0083] Memory 8230 can store a variety of data required by the components of the electronic device 8201 (such as the processor 8220 and the sensor module 8276). This data may include, for example, software (such as the program 8240) and input and / or output data for related instructions. Memory 8230 may include volatile memory 8232 and / or non-volatile memory 8234.

[0084] Program 8240 is stored as software in memory 8230 and may include an operating system 8242, middleware 8244, and / or application 8246.

[0085] The input device 8250 can receive instructions and / or data used by components of the electronic device 8201 (such as the processor 8220) from outside the electronic device 8201 (such as a user). The input device 8250 may include a remote control, microphone, mouse, keyboard, and / or digital pen (such as a stylus pen).

[0086] The acoustic output device 8255 can output an acoustic signal to the outside of the electronic device 8201. The acoustic output device 8255 may include a speaker and / or a receiver. The speaker may be used for general purposes such as multimedia playback or recording and playback, and the receiver may be used to receive incoming telephone calls. The receiver may be coupled as part of the speaker or may be embodied as a separate, independent device.

[0087] The display device 8260 can visually provide information to the outside of the electronic device 8201. The display device 8260 may include a display, a hologram device, or a projector and a control circuit for controlling said device. The display device 8260 may include a display device according to an exemplary embodiment. The display device 8260 may include a touch circuitry configured to sense touches and / or a sensor circuitry (such as a pressure sensor) configured to measure the intensity of the force generated by the touch.

[0088] The audio module 8270 converts sound into electrical signals and vice versa. The audio module 8270 can acquire sound through the input device 8250 and output sound through the speakers and / or headphones of the sound output device 8255 and / or other electronic devices (such as electronic device 8202) directly or wirelessly connected to the electronic device 8201.

[0089] The sensor module 8276 can sense the operating state of the electronic device 8201 (power, temperature, etc.) or the external environmental state (user state, etc.), and generate electrical signals and / or data values ​​corresponding to the sensed state. The sensor module 8276 may include a gesture sensor, gyro sensor, barometric pressure sensor, magnetic sensor, acceleration sensor, grip sensor, proximity sensor, color sensor, IR (Infrared) sensor, biosensor, temperature sensor, humidity sensor, and / or illuminance sensor.

[0090] Interface 8277 can support one or more designated protocols used to connect electronic device 8201 directly or wirelessly with other electronic devices (such as electronic device 8202). Interface 8277 may include HDMI® (High Definition Multimedia Interface), USB (Universal Serial Bus) interface, SD card interface, and / or audio interface.

[0091] The coupling terminal 8278 may include a connector that physically connects the electronic device 8201 to another electronic device (such as the electronic device 8202). The coupling terminal 8278 may include an HDMI connector, a USB connector, an SD card connector, and / or an audio connector (such as a headphone connector).

[0092] The haptic module 8279 can convert electrical signals into mechanical stimuli (such as vibration or movement) or electrical stimuli that the user perceives through touch or kinesthetic sense. The haptic module 8279 may include a motor, a piezoelectric element, and / or an electrical stimulator.

[0093] The camera module 8280 can capture still images and videos. The camera module 8280 may include a lens assembly containing one or more lenses, an image sensor, an image signal processor, and / or a flash. The lens assembly included in the camera module 8280 can collect light emitted from the subject being imaged.

[0094] The power management module 8288 can manage the power supplied to the electronic device 8201. The power management module 8388 can be implemented as part of a Power Management Integrated Circuit (PMIC).

[0095] The battery 8289 can supply power to the components of the electronic device 8201. The battery 8289 may include a non-rechargeable primary battery, a rechargeable secondary battery, and / or a fuel cell.

[0096] The communication module 8290 can assist in establishing direct wired and / or wireless communication channels between the electronic device 8201 and other electronic devices (such as electronic devices 8202, 8204, and server 8208), and in performing communication over the established communication channels. The communication module 8290 operates independently of the processor 8220 (such as an application processor) and may include one or more communication processors that support direct and / or wireless communication. The communication module 8290 may include wireless communication modules 8292 (such as cellular communication modules, short-range wireless communication modules, and GNSS (Global Navigation Satellite System) modules) and / or wired communication modules 8294 (such as LAN (Local Area Network) communication modules and power line communication modules). Of these communication modules, the communication module can communicate with other electronic devices through a first network 8298 (a short-range communication network such as Bluetooth®, WiFi Direct, or IrDA (Infrared Data Association)) or a second network 8299 (a long-range communication network such as a cellular network, the Internet, or a computer network (LAN, WAN, etc.)). These various types of communication modules may be integrated into a single component (such as a single chip) or embodied as multiple separate components (multiple chips). The wireless communication module 8292 can verify and authenticate the electronic device 8201 within a communication network such as the first network 8298 and / or the second network 8299 using subscriber information (such as an International Mobile Subscriber Identifier (IMSI)) stored in the subscriber identification module 8296.

[0097] The antenna module 8297 transmits and / or receives signals and / or power to or from an external source (such as other electronic devices). The antenna may include a radiator consisting of a conductive pattern formed on a substrate (such as a PCB). The antenna module 8297 may include one or more antennas. If multiple antennas are included, the communication module 8290 may select an antenna from among the multiple antennas that is suitable for the communication scheme used in the communication network, such as the first network 8298 and / or the second network 8299. Signals and / or power may be transmitted or received between the communication module 8290 and other electronic devices through the selected antenna. Other components (such as an RFIC) may be included as part of the antenna module 8297 in addition to the antenna.

[0098] Some of the components are interconnected through communication methods between peripheral devices (bus, GPIO (General Purpose Input and Output), SPI (Serial Peripheral Interface, MIPI (Mobile Industry Processor Interface), etc.)), allowing them to exchange signals, commands, data, and other information with each other.

[0099] Commands or data may be transmitted to or received between electronic device 8201 and external electronic device 8204 via server 8208 connected to the second network 8299. Other electronic devices 8202 and 8204 are devices of the same or different type as electronic device 8201. All or part of the operations performed by electronic device 8201 may be performed by one or more of the other electronic devices 8202, 8204, and 8208. For example, when electronic device 8201 needs to perform a certain function or service, instead of performing the function or service itself, it can request one or more other electronic devices to perform part or all of that function or service. One or more other electronic devices that receive the request can perform the additional functions or services related to the request and communicate the results of their execution to electronic device 8201. Cloud computing, distributed computing, and / or client-server computing technologies may be used for this purpose.

[0100] Figure 27 is a drawing showing an example of an electronic device according to an exemplary embodiment being applied to a mobile device. The mobile device 9100 includes a display device 9110, which may include a display device according to an exemplary embodiment. The display device 9110 may have a foldable structure, for example, a multi-fold structure.

[0101] Figure 28 is a drawing showing an example of a display device according to an exemplary embodiment applied to an automobile. The display device is an automobile head-up display device 9200, which may include a display 9210 provided in a region of the automobile and an optical path changing member 9220 that converts the optical path so that the image generated by the display 9210 can be viewed by the driver.

[0102] Figure 29 is a drawing showing an example of a display device according to an exemplary embodiment applied to augmented reality glasses or virtual reality glasses. The augmented reality glasses 9300 may include a projection system 9310 that forms an image and a waveguide 9320 that directs the image from the projection system 9310 to the user's eyes. The projection system 9310 may include a display device according to an exemplary embodiment. The waveguide 9320 may be provided, for example, in the glasses frame.

[0103] Figure 30 is a diagram showing an example of a display device according to an exemplary embodiment applied to large-scale signage. The signage 9400 is used for outdoor advertising utilizing a digital information display, and the advertising content can be controlled via a communication network. The signage 9400 can be implemented, for example, through an electronic device described with reference to Figure 26.

[0104] Figure 31 is a drawing showing an example of a display device according to an exemplary embodiment applied to a wearable display. The wearable display 9500 includes a display device according to an exemplary embodiment and can be embodied through an electronic device described with reference to Figure 26.

[0105] The display device according to this exemplary embodiment can also be applied to a variety of other products, such as rollable TVs and stretchable displays.

[0106] The embodiments described above are merely illustrative, and a person with ordinary skill in the art can derive a variety of variations and equivalent other embodiments from them. Therefore, the true scope of technical protection provided by the exemplary embodiments must be determined by the technical idea set forth in the claims below. [Explanation of Symbols]

[0107] 110 Backplane PCB 120 First Epitaxial Structure 130 Second epitaxial structure 140 Third epitaxial structure 150,251,252 Anti-reflection layer 160 lens

Claims

1. A backplane substrate including at least one drive element, A first epitaxial structure, a second epitaxial structure, and a third epitaxial structure are sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, The lens provided in the third epitaxial structure, The third epitaxial structure and the lens are included, Each of the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure includes a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer. The first epitaxial structure is configured to emit light of a first wavelength, the second epitaxial structure to emit light of a second wavelength, and the third epitaxial structure to emit light of a third wavelength. The anti-reflective layer comprises a material having a refractive index in the range of 1.7 to 2.1 and has a thickness in the range of 75 nm to 110 nm, in a display device.

2. The display device according to claim 1, wherein the first epitaxial structure emits red wavelength light, the second epitaxial structure emits green wavelength light, and the third epitaxial structure emits blue wavelength light.

3. The display apparatus according to claim 1, further comprising a reflective layer between the backplane substrate and the first epitaxial structure.

4. The display device according to claim 1, wherein a first p-type electrode, a second p-type electrode, and a third p-type electrode are provided spaced apart between the backplane substrate and the first epitaxial structure, and an n-type electrode is provided between the third epitaxial structure and the anti-reflective layer.

5. The display device according to claim 1, wherein the display device includes a plurality of pixels, each of the plurality of pixels includes the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure, and the anti-reflective layer is connected to the plurality of pixels as a single body.

6. The display device according to claim 1, wherein the display device includes a plurality of pixels, each of the plurality of pixels includes the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure, and the anti-reflective layer is provided individually for each of the plurality of pixels.

7. The display device according to claim 1, wherein, when the refractive index of the second conductive semiconductor layer of the third epitaxial structure is n1, the refractive index of the anti-reflective layer is n2, and the refractive index of the lens is n3, the condition n1 > n2 > n3 is satisfied.

8. A backplane substrate including at least one drive element, A first epitaxial structure, a second epitaxial structure, and a third epitaxial structure are sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, The lens provided in the third epitaxial structure, The third epitaxial structure and the lens are provided with a first anti-reflective layer and a second anti-reflective layer, which are provided sequentially from the third epitaxial structure. Each of the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure includes a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer. The first epitaxial structure is configured to emit light of a first wavelength, the second epitaxial structure to emit light of a second wavelength, and the third epitaxial structure to emit light of a third wavelength. The first anti-reflective layer includes a first refractive index, and the second anti-reflective layer includes a second refractive index smaller than the first refractive index. A display device wherein the first anti-reflective layer and the second anti-reflective layer have a thickness greater than 0 and less than or equal to 200 nm.

9. The display device according to claim 8, wherein the first epitaxial structure emits red wavelength light, the second epitaxial structure emits green wavelength light, and the third epitaxial structure emits blue wavelength light.

10. The display apparatus according to claim 8, further comprising a reflective layer between the backplane substrate and the first epitaxial structure.

11. The display apparatus according to claim 8, wherein the first anti-reflective layer has a refractive index of 1.9 or higher, and the second anti-reflective layer has a refractive index of 1.9 or lower.

12. The display device according to claim 8, wherein, when the refractive index of the second conductive semiconductor layer of the third epitaxial structure is n1, the refractive index of the first anti-reflective layer is n21, the refractive index of the second anti-reflective layer is n22, and the refractive index of the lens is n3, the condition n1 > n21 > n22 > n3 is satisfied.

13. The steps include forming a third epitaxial structure on the substrate, The steps include forming a second epitaxial structure on the third epitaxial structure, The steps include forming a first epitaxial structure on top of the second epitaxial structure to prepare a vertically stacked structure, The steps include forming a backplane substrate and The steps include: positioning the first epitaxial structure opposite the backplane substrate and bonding the backplane substrate and the vertical stacked structure; The step of removing the aforementioned substrate, The steps include forming an anti-reflective layer on the third epitaxial structure, The step includes forming a lens on the anti-reflective layer, The steps of forming the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure each include the steps of forming a first conductivity type semiconductor layer, forming an active layer, and forming a second conductivity type semiconductor layer, respectively. A method for manufacturing a display device, wherein the anti-reflective layer comprises a substance having a refractive index in the range of 1.7 to 2.1 and has a thickness in the range of 75 nm to 110 nm.

14. A method for manufacturing a display device according to claim 13, wherein the first epitaxial structure emits red wavelength light, the second epitaxial structure emits green wavelength light, and the third epitaxial structure emits blue wavelength light.

15. A method for manufacturing a display device according to claim 13, wherein a first p-type electrode, a second p-type electrode, and a third p-type electrode are provided spaced apart between the backplane substrate and the first epitaxial structure, and an n-type electrode is provided between the third epitaxial structure and the anti-reflective layer.

16. A method for manufacturing a display device according to claim 13, wherein, when the refractive index of the second conductive semiconductor layer of the third epitaxial structure is n1, the refractive index of the anti-reflective layer is n2, and the refractive index of the lens is n3, the condition n1 > n2 > n3 is satisfied.

17. A display device that forms an image, The waveguide includes, which guides the aforementioned image to the user's eyes. The aforementioned display device is A backplane substrate including at least one drive element, A first epitaxial structure, a second epitaxial structure, and a third epitaxial structure are sequentially stacked from the backplane substrate in a direction perpendicular to the backplane substrate, The lens provided in the third epitaxial structure, The third epitaxial structure and the lens are included, Each of the first epitaxial structure, the second epitaxial structure, and the third epitaxial structure includes a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer. The first epitaxial structure is configured to emit light of a first wavelength, the second epitaxial structure to emit light of a second wavelength, and the third epitaxial structure to emit light of a third wavelength. The anti-reflective layer comprises a material having a refractive index in the range of 1.7 to 2.1 and has a thickness in the range of 75 nm to 110 nm, in an electronic device.

18. The electronic device according to claim 17, wherein the first epitaxial structure emits red wavelength light, the second epitaxial structure emits green wavelength light, and the third epitaxial structure emits blue wavelength light.

19. The electronic device according to claim 17, wherein a first p-type electrode, a second p-type electrode, and a third p-type electrode are provided spaced apart between the backplane substrate and the first epitaxial structure, and an n-type electrode is provided between the third epitaxial structure and the anti-reflective layer.

20. The electronic device according to claim 17, wherein when the refractive index of the second conductive semiconductor layer of the third epitaxial structure is n1, the refractive index of the anti-reflective layer is n2, and the refractive index of the lens is n3, the condition n1 > n2 > n3 is satisfied.

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