Semiconductor Light-Emitting Diode and Method for Manufacturing the Same

Abstract

To provide a semiconductor light-emitting diode and a manufacturing method for the same.SOLUTION: A semiconductor light-emitting diode and a manufacturing method for the same are provided. The semiconductor light-emitting diode includes a first semiconductor layer, a plurality of active elements arranged apart from each other in the first semiconductor layer and each having a width smaller than the width of the first semiconductor layer, and a second semiconductor layer disposed on the active elements.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a semiconductor light emitting diode and a method for manufacturing the same.

Background Art

[0002] A light emitting diode (LED) is known as a next-generation light source having advantages such as long life, low power consumption, fast response speed, and environmental friendliness compared to conventional light sources, and is used in various products such as lighting devices and backlights of display devices. In particular, group III nitride-based LEDs such as gallium nitride (GaN), aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), and indium aluminum gallium nitride (InAlGaN) serve as semiconductor light emitting elements that output light.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The problem to be solved by the present invention is to provide a semiconductor light emitting diode with improved luminous efficiency and a method for manufacturing the same.

[0004] The problem to be solved by the present invention is also to provide a semiconductor light emitting diode including an active layer with a large lattice mismatch and a method for manufacturing the same.

Means for Solving the Problems

[0005] According to one type, a semiconductor light emitting diode includes a first semiconductor layer, a plurality of active elements spaced apart from each other in the first semiconductor layer and each having a width narrower than the width of the first semiconductor layer, and a second semiconductor layer disposed on the plurality of active elements.

[0006] And each of the plurality of active elements can have one end in contact with the first semiconductor layer and the other end in contact with the second semiconductor layer.

[0007] Further, the plurality of active elements are also arranged in a direction parallel to the width direction of the first semiconductor layer. And each of the plurality of active elements is also in a strained state.

[0008] Also, the width of each of the plurality of active elements is also 10 nm or more and 100 nm or less. And the pitch between the plurality of active elements is also 20 nm or more and 300 nm or less.

[0009] Further, the first semiconductor layer may include a plurality of first semiconductor elements that are spaced apart while being in contact with each of the plurality of active elements, and a first semiconductor common layer that is in contact with the plurality of first semiconductor elements.

[0010] And the plurality of first semiconductor elements and the first semiconductor common layer are also formed of the same material.

[0011] Further, the second semiconductor layer may include a plurality of second semiconductor elements that are spaced apart while being in contact with the plurality of active elements.

[0012] And the second semiconductor layer may further include a second semiconductor common layer that is in contact with each of the plurality of second semiconductor elements.

[0013] Further, it may further include an insulating layer disposed between the plurality of active elements. And the insulating layer may include a mesh structure.

[0014] Also, each of the plurality of active elements contains In x Ga 1-x N (0 ≦ x ≦ 1) may be included.

[0015] And the In content of each of the plurality of active elements is also 35% or more. Also, each of the plurality of active elements can emit red light.

[0016] On one hand, a display device according to an embodiment includes a substrate, a display element layer disposed on the substrate and including a plurality of light-emitting diodes, and a driving element layer including a plurality of transistors electrically connected to the plurality of light-emitting diodes for driving the plurality of light-emitting diodes. At least one of the plurality of light-emitting diodes includes a first semiconductor and a second semiconductor layer disposed apart from each other, and a plurality of active elements disposed in a spaced-apart arrangement between the first semiconductor and the second semiconductor layer, each of the widths of which is narrower than the width of the first semiconductor layer.

[0017] And it may further include a first electrode in contact with the first semiconductor layer and a second electrode in contact with the second semiconductor layer.

[0018] Also, the first electrode, the first semiconductor layer, the plurality of active elements, the second semiconductor layer, and the second electrode may be sequentially arranged in one direction.

[0019] And the first electrode, the first semiconductor layer, the plurality of active elements, the second semiconductor layer, and the second electrode are also arranged in a direction perpendicular to the thickness direction of the substrate.

[0020] Also, the first electrode, the first semiconductor layer, the plurality of active elements, the second semiconductor layer, and the second electrode are also arranged in a direction parallel to the thickness direction of the substrate.

[0021] And each of the plurality of active elements can have one end in contact with the first semiconductor layer and the other end in contact with the second semiconductor layer.

[0022] Also, each of the plurality of active elements is in a strained state. And the width of each of the plurality of active elements is also 10 nm or more and 100 nm or less.

[0023] Also, the first semiconductor layer may include a plurality of first semiconductor elements disposed apart from each other while being in contact with each of the plurality of active elements, and a first semiconductor common layer in contact with the plurality of first semiconductor elements.

[0024] And, on the first semiconductor layer, an insulating layer disposed between the plurality of active elements may be further included. Further, the insulating layer may include a mesh structure.

[0025] And each of the plurality of active elements may include In x Ga 1-x N (0.35 ≦ x ≦ 1). Also, each of the plurality of active elements can emit red light.

[0026] On the other hand, a method for manufacturing a semiconductor light-emitting diode according to an embodiment includes a step of forming a first semiconductor common layer on a substrate, a step of forming an insulating layer including a plurality of openings on the first semiconductor common layer, a step of forming a plurality of active elements in the plurality of openings, and a step of forming a second semiconductor layer on the plurality of active elements.

[0027] And, before forming the plurality of active elements, a step of forming a plurality of first semiconductor elements in the plurality of openings may be further included.

[0028] Also, the step of forming the second semiconductor layer may include a step of forming a plurality of second semiconductor elements in the plurality of openings.

[0029] And, the step of forming the second semiconductor layer may further include a step of forming a second semiconductor common layer in contact with the plurality of second semiconductor elements and the insulating layer.

Brief Description of Drawings

[0030]

Figure 1

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Figure 16

Embodiments for Carrying Out the Invention

[0031] Hereinafter, with reference to the accompanying drawings, embodiments will be described in detail. The described embodiments are merely exemplary, and various modifications are possible from such embodiments. In the following drawings, the same reference numerals denote the same components, and on the drawings, the size of each component may be exaggerated for clarity and convenience of explanation.

[0032] Hereinafter, the terms "upper part" and "above" described herein may include not only those in direct contact and directly above but also those not in contact and above.

[0033] Terms such as first and second are also used in the description of various components, but are used only for the purpose of distinguishing one component from another. Such terms do not limit that the substances or structures of the components are different.

[0034] Singular expressions include plural expressions unless the context clearly indicates otherwise. Also, when a part "includes" a certain component, it means that, unless there is a special contrary description, it does not exclude other components and may further include other components.

[0035] Also, terms such as "part" and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software, or by a combination of hardware and software.

[0036] The use of the term "the foregoing" and similar directive terms applies to both singular and plural.

[0037] The steps constituting a method may be performed in an appropriate order unless there is an explicit mention that they must be performed in the described order. Also, the use of all exemplary terms (e.g., "for example") is merely for the purpose of explaining the technical idea in detail, and the scope of rights is not limited by such terms unless limited by the claims.

[0038] Figure 1 is a cross-sectional view showing a semiconductor light-emitting diode according to an embodiment. As shown in Figure 1, the semiconductor light-emitting diode 100 is also an inorganic LED (light emitting diode), and can emit light of a specific wavelength by the substances contained in the light-emitting diode 100. The light-emitting diode 100 may include a first semiconductor layer 110, an active layer 120, and a second semiconductor layer 130.

[0039] The first semiconductor layer 110 may include, for example, an n-type semiconductor. However, it is not necessarily limited thereto, and in some cases, the first semiconductor layer 110 may include a p-type semiconductor. The first semiconductor layer 110 may include a III-V group-based n-type semiconductor, for example, n-GaN. Such a first semiconductor layer 110 can have a single-layer structure or a multilayer structure. For example, the first semiconductor layer 110 includes any one semiconductor material of InAlGaN, GaN, AlGaN, InGaN, AlN, InN, and may include a semiconductor layer doped with a conductive dopant such as Si, Ge, Sn.

[0040] The active layer 120 is also disposed on the upper surface of the first semiconductor layer 110. The active layer 120 can generate light while electrons and holes are combined, and can have a multi-quantum well (MQW) structure or a single-quantum well (SQW) structure. Such an active layer 120 may include a III-V group-based semiconductor, for example, InGaN, GaN, AlGaN, AlInGaN, etc. A clad layer (not shown) doped with a conductive dopant may also be formed on the upper and / or lower portions of the active layer 120. As an example, the clad layer may also be implemented by an AlGaN layer or an InAlGaN layer.

[0041] The second semiconductor layer 130 is provided on the active layer 120 and may include a semiconductor layer of a type different from that of the first semiconductor layer 110. For example, the second semiconductor layer 130 may include a p-type semiconductor layer. The second semiconductor layer 130 includes, for example, InAlGaN, GaN, AlGaN, and / or InGaN, and is also a semiconductor layer doped with a conductive dopant such as Mg.

[0042] In addition to the first semiconductor layer 110, the active layer 120, and the second semiconductor layer 130 described above, the light-emitting diode 100 may further include other cladding layers and / or electrodes above and / or below each layer.

[0043] The wavelength of the light emitted may vary depending on the material content in the active layer 120. The higher the In content, the larger the wavelength of the emitted light. For example, when the In content of the active layer 120 is about 15%, the active layer 120 emits blue light of about 450 nm, and when the In content of the active layer 120 is about 25%, the active layer 120 can emit green light of about 520 nm. When the In content of the active layer 120 is about 35%, the active layer 120 can emit red light of about 630 nm.

[0044] On the other hand, in the conventional active layer, as the In content increases and the wavelength of the emitted light becomes larger, the efficiency of the light-emitting diode decreases rapidly. FIG. 2 is a graph showing the light-emitting efficiency according to the wavelength of the conventional active layer. As shown in FIG. 2, when the active layer is formed of a material that emits blue light of about 450 nm, the maximum value of the external quantum efficiency of the active layer is about 0.7. However, when the active layer is formed of a material that emits red light of about 630 nm, the maximum value of the external quantum efficiency of the active layer is less than 0.1. This is because as the In content increases, lattice mismatch between materials in the active layer, for example, InGaN and GaN, occurs. Such lattice mismatch induces strain in the materials in the active layer or generates defects, and the strain changes the phase separation state of the active layer.

[0045] Figure 3A is a graph showing the phase separation state according to the material content of In x Ga (1-y) N, and Figure 3B is a graph showing the phase separation state according to the material content of In x Ga (1-y) N in the strained state.

[0046] As shown in Figures 3A and 3B, when In x Ga (1-y) N in the relaxed state contains an In content of 0.5 or less, depending on the temperature, In x Ga (1-y) N is also in a spinodal state or a binodal state. In particular, when the In content is about 0.3 to 0.5, in most temperature ranges, In x Ga (1-y) N will be in a spinodal state. In such a spinodal state, the active layer becomes unstable, which means that it can be a constraint in the manufacturing process of a light-emitting diode including such an active layer.

[0047] According to Figure 3B, when In x Ga (1-y) N in the strained state contains an In content of 0.5 or less, for example, 0.3 to 0.5, the active layer will be in a binodal state in all temperature ranges. Therefore, if the In content is 0.5 or less and in a strained state, it means that In x Ga (1-y) N can maintain a stable state regardless of the temperature. Such a strained state can be obtained if the active layer has a lattice mismatch.

[0048] On the other hand, the strain generated by the lattice mismatch can disappear if the thickness of the active layer increases and defects such as dislocations are created. Therefore, it is desirable to obtain an active layer that maintains a strained state without generating defects.

[0049] The width and thickness of the active layer having strain are also determined by the lattice constant of the material in the active layer. FIG. 4 is a drawing showing the relationship between the width and thickness capable of maintaining strain by material according to one embodiment. As shown in FIG. 4, it can be confirmed that the width and thickness capable of maintaining strain differ depending on the material. Also, even for the same material, the greater the width, the thinner the thickness capable of maintaining strain. For example, if In 0.5 Ga 0.5 N is laminated on the GaN layer, if it is laminated to a thickness of about 0.5 nm or less, In 0.5 Ga 0.5 N can maintain strain. However, laminating the layer to a thickness of 0.5 nm or less causes many difficulties in the process.

[0050] To overcome such process difficulties, the width of the active layer can be narrowed to maintain strain. For example, if In 0.5 Ga 0.5 N is laminated to a thickness of 1 nm or more, by forming the width to 30 nm or less, generation of defects can be reduced and strain can be maintained. In particular, when laminating a material with a large lattice mismatch, generation of defects can be effectively reduced by restricting the width.

[0051] Therefore, the active layer 120 according to one embodiment may include a plurality of active elements 122 having a nano-sized width. Also referring to FIG. 1, the active layer 120 may include a plurality of active elements 122 spaced apart on the first semiconductor layer 110. The plurality of active elements 122 are arranged one-dimensionally or two-dimensionally in a direction parallel to the width W 1 of the first semiconductor layer 110.

[0052] The width W 2 of each active element 122 is also nano-sized. For example, the width W 2is also in the range of about 10 nm to about 100 nm. The pitch P between the active elements 122 is 10 μm or less, for example, also in the range of about 20 nm to about 300 nm. The thickness of each active element 122 is also in the range of 1 nm to 100 nm. Thus, the width W of the active element 122 2 Due to the narrow width of the active element 122, even if the lattice mismatch within the active element 122 or the lattice mismatch between the active element 122 and the first semiconductor 110 and the second semiconductor layer 130 is large, the generation of defects can be reduced.

[0053] Thus, if the active layer 120 is composed of a plurality of narrow-width active elements 122, even when the In content is high, the generation of defects can be prevented and light with high optical efficiency can be emitted. For example, the active element 122 may contain x Ga 1-x InGaN (0 ≦ x ≦ 1), and the In content is also 35% or more capable of emitting red light.

[0054] On the other hand, the first semiconductor layer 110 may include a first semiconductor common layer 112 and a plurality of first semiconductor elements 114 spaced apart on the first semiconductor common layer 112. The first semiconductor common layer 112 and the plurality of first semiconductor elements 114 may also be formed of the same material, and the width W of the first semiconductor common layer 112 1 is also the width of the light-emitting diode 100. The first semiconductor common layer 112 can have a width of about 1 μm or less, for example, about 600 nm or less.

[0055] The plurality of first semiconductor elements 114 are spaced apart on the first semiconductor common layer 112 and can be arranged and brought into contact so that each overlaps with the active element 122. The width W of each of the first semiconductor elements 114 2 is also the same as the width W2 of the active element 122. For example, the width W of the first semiconductor element 114 2は, it is also in the range of about 10 nm or more and about 100 nm or less. And the pitch P between the first semiconductor elements 114 is 10 μm or less, for example, it is also in the range of about 20 nm or more and about 300 nm or less. The first semiconductor element 114 serves as a seed layer when the active element 122 grows. Since its width is narrow, even if there is a lattice mismatch between the first semiconductor element 114 and the active element 122, no defects are generated.

[0056] As described above, the first semiconductor layer 110 includes the first semiconductor common layer 112 and the first semiconductor elements 114. Through the wide first semiconductor common layer 112, it can stably provide electrons or holes to the active layer 120, and through the narrow first semiconductor elements 114, the generation of defects in the active elements 122 can be prevented.

[0057] The second semiconductor layer 130 may include a plurality of second semiconductor elements 132 arranged separately. Each of the second semiconductor elements 132 can be arranged to overlap and contact the active element 122, and the width of each is the same as the width of the active element 122. The width of the second semiconductor element 132 is in the range of about 10 nm or more and about 100 nm or less, and the pitch P between the second semiconductor elements 132 is 10 μm or less, for example, it is also in the range of about 20 nm or more and about 300 nm or less. Even if there is a lattice mismatch between the second semiconductor element 132 and the active element 122, no defects are generated because the width of the second semiconductor element 132 is narrow.

[0058] FIG. 5 is a drawing showing a light-emitting element including a light-emitting diode according to an embodiment. As shown in FIG. 5, the light-emitting element 200 may include a substrate 210, a light-emitting diode 100 disposed on the substrate 210, and a first electrode 220 and a second electrode 230 in contact with the light-emitting diode 100.

[0059] The substrate 210 may include an insulating material such as glass, organic polymer, or crystal. Also, the substrate 210 can be made of a flexible material so that it can warp or be folded, and can have a single-layer structure or a multilayer structure. The substrate 210 may include a transistor or the like that can drive the light-emitting diode 100.

[0060] The light-emitting diode 100 may include a first semiconductor layer 110, an active layer 120, and a second semiconductor layer 130 illustrated in FIG. 1. As described with reference to FIG. 1, the first semiconductor layer 110 includes a first semiconductor common layer 112 and a plurality of first semiconductor elements 114, the active layer 120 includes a plurality of active elements 122, and the second semiconductor layer 130 may include a plurality of second semiconductor elements 132. Since each component of the light-emitting diode 100 has already been described, a detailed description thereof will be omitted.

[0061] The thickness direction of the light-emitting diode 100 and the thickness direction of the substrate 210 are also perpendicular to each other. For example, as shown in FIG. 5, the first semiconductor layer 110, the active layer 120, and the second semiconductor layer 130 of the light-emitting diode 100 may be sequentially arranged in a direction perpendicular to the thickness direction of the substrate 210. Light of a desired wavelength can be emitted from a plurality of active elements 122 stacked in the thickness direction of the substrate 210.

[0062] The first electrode 220 and the second electrode 230 are also disposed on the substrate 210. The first electrode 220 and the second electrode 230 sandwich the light-emitting diode 100 and are spaced apart from each other. The first electrode 220 is disposed to be in contact with the first semiconductor layer 110, and the second electrode 230 is also disposed to be in contact with the second semiconductor layer 130. The first electrode 220 and the second electrode 230 are also disposed on the same plane and can have the same thickness. If the first electrode 220 and the second electrode 230 have the same thickness, the light-emitting diode 100 can be stably connected by the first electrode 220 and the second electrode 230.

[0063] The first electrode 220 and the second electrode 230 are also made of a conductive material. Examples of the conductive material include metals such as Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, and alloys thereof; conductive oxides such as ITO (indium tin oxide), IZO (indium zinc oxide), ZnO (zinc oxide), and ITZO (indium tin zinc oxide); and conductive polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT).

[0064] Figures 6A to 6H are diagrams for explaining a method of manufacturing a light-emitting element according to an embodiment.

[0065] First, as shown in FIG. 6A, a first semiconductor common layer 112 can be formed on a base substrate 310. The base substrate 310 also serves as a substrate for growing the light-emitting diode 100. The base substrate 310 may include various materials used in general semiconductor processes. For example, as the base substrate 310, a silicon substrate or a sapphire substrate can be used.

[0066] The first semiconductor common layer 112 can be formed using a method such as metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), or hydride vapor phase epitaxy (HVPE). The first semiconductor common layer 112 is also formed to have a thickness of about 5 μm or less.

[0067] Then, an insulating layer 320 including a plurality of openings h can be formed on the first semiconductor common layer 112. The insulating layer 320 is also a mesh structure including a plurality of openings h. For example, after forming an insulating material layer on the first semiconductor common layer 112, the openings h can be patterned. The size of the openings h is also about 10 nm or more and about 100 nm or less, and the shape of the openings h is also circular, elliptical, and / or polygonal. The plurality of openings h are arranged one-dimensionally or two-dimensionally and can have the same or different sizes. The shape and width of the openings h and the like can determine the shape and width of the first semiconductor element 114, the active element 122, the second semiconductor element 132, etc. to be formed later.

[0068] As shown in FIG. 6B, the first semiconductor element 114, the active element 122, and the second semiconductor element 132 can be formed by growing a first semiconductor material, an active material, and a second semiconductor material in a plurality of openings h. The first semiconductor element 114, the active element 122, and the second semiconductor element 132 can also be formed by using methods such as metalorganic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE).

[0069] As shown in FIG. 6C, a mask 330 spaced apart at a constant interval H can be disposed on the insulating layer 320. The width of the mask 330 thus spaced apart can determine the width W of the light-emitting diode 100 1 and is, for example, also 600 nm or less.

[0070] As shown in FIG. 6D, in the material stacked on the substrate 310, the material in the region (constant interval H) that does not overlap with the mask 330 can be removed by etching.

[0071] As shown in FIG. 6E, the mask 330 is removed. The process of using the mask 330 to obtain a plurality of light-emitting diodes is described with reference to FIGS. 6C to 6E. When manufacturing one light-emitting diode, the process of using such a mask 330 is not necessary, and the processes of FIGS. 6C to 6E can be omitted.

[0072] Next, as shown in FIG. 6F, the insulating layer 320 can be removed by etching.

[0073] As shown in FIG. 6G, after the light-emitting diode 100 is separated from the substrate 310, it can be transferred to the substrate 210.

[0074] As shown in FIG. 6H, the first electrode 220 and the second electrode 230 can be formed on the substrate 210. The first electrode 220 can be formed so as to be in contact with the first semiconductor layer 110 of the light-emitting diode 100, and the second electrode 230 can be formed so as to be in contact with the second semiconductor layer 130 of the light-emitting diode 100.

[0075] In FIGS. 6G and 6H, after transferring the light-emitting diode onto the substrate 210, the first electrode 220 and the second electrode 230 are formed, but the present invention is not limited thereto. After forming the electrodes on the substrate 210, the light-emitting diode may also be transferred.

[0076] FIGS. 7A to 7C are diagrams for explaining a method of manufacturing a light-emitting element according to another embodiment.

[0077] As shown in FIG. 7A, the first sub-electrode 221 and the second sub-electrode 231 are formed on the substrate 210, and a solution S containing the light-emitting diode 100 can be sprayed onto the region between the first sub-electrode 221 and the second sub-electrode 231. For the spraying of the solution S, an inkjet printing method can be used, but the present invention is not limited thereto.

[0078] As shown in FIG. 7B, if an electric field is applied between the first sub-electrode 221 and the second sub-electrode 231, the light-emitting diode 100 is self-aligned between the first sub-electrode 221 and the second sub-electrode 231 by the electric field. Instead of applying the electric field after spraying the solution S, the solution S containing the light-emitting diode 100 can also be sprayed while an electric field is applied between the first sub-electrode 221 and the second sub-electrode 231.

[0079] If the light-emitting diode 100 is self-aligned, as shown in FIG. 7C, a first contact electrode 222 for electrically and / or physically stably connecting the light-emitting diode 100 corresponding to the first sub-electrode 221 is formed on the first sub-electrode 221, and a second contact electrode 232 for electrically and / or physically stably connecting the light-emitting diode 100 corresponding to the second sub-electrode 231 is formed on the second sub-electrode 231. Each of the first contact electrode 222 and the second contact electrode 232 makes a resistive contact with the first sub-electrode 221 and the second sub-electrode 231, and the light-emitting diode 100. Here, the first sub-electrode 221 and the first contact electrode 222 are referred to as the first electrode, and the second sub-electrode 231 and the second contact electrode 232 are referred to as the second electrode.

[0080] FIG. 8 is a drawing showing a light-emitting diode according to another embodiment. Comparing FIG. 1 and FIG. 8, the light-emitting diode 100a in FIG. 8 may further include an insulating layer 140 between a plurality of active elements 122. The insulating layer 140 may include a mesh structure. The insulating layer 140 included in FIG. 8 is also the insulating layer 320 formed at the stage of FIG. 6B, and is also an insulating layer formed of another insulating material after the insulating layer 320 is removed in FIG. 6F.

[0081] FIG. 9 is a drawing showing a light-emitting diode according to still another embodiment. Comparing FIG. 8 and FIG. 9, the second semiconductor layer 130a of the light-emitting diode 100b shown in FIG. 9 may further include a second semiconductor common layer 134. The second semiconductor common layer 134 is also formed of the same material as the second semiconductor element 132. By connecting an electrode to the second semiconductor common layer 134, electrons or holes can be stably supplied to the active layer 120.

[0082] FIGS. 10A to 10H are drawings for explaining a method of manufacturing a light-emitting element including a light-emitting diode according to another embodiment. In the following, the explanation will be centered on the differences from the method of manufacturing the light-emitting element described in FIGS. 6A to 6H.

[0083] First, as shown in FIG. 10A, a first semiconductor common layer 112 can be formed on a base substrate 310. The base substrate 310 also serves as a substrate for growing the light-emitting diode 100. The base substrate 310 may include various materials used in general semiconductor processes. Then, an insulating layer 320 including a plurality of openings h can be formed on the first semiconductor common layer 112.

[0084] As shown in FIG. 10B, by growing a first semiconductor material, an active material, and a second semiconductor material in the plurality of openings h, a first semiconductor element 114, an active element 122, and a second semiconductor element 132 can be formed. Then, a second semiconductor common layer 134 can be further formed on the insulating layer 320 and on the second semiconductor element 132. The second semiconductor common layer 134 is also formed in the same manner as the second semiconductor element 132.

[0085] As shown in FIG. 10C, masks 330 can be arranged at regular intervals on the insulating layer 320 and on the second semiconductor element 132. The width of the mask 330 can determine the width of the light-emitting diode. As shown in FIG. 10D, in the materials stacked on the base substrate 310, the materials in the region H that do not overlap with the mask 330 can be removed. Then, as shown in FIG. 10E, the mask 330 can be removed.

[0086] Next, as shown in FIG. 10F, the light-emitting diode 100b can be transferred onto the substrate 210, and as shown in FIG. 10G, a first electrode 220 and a second electrode 230 can be formed on the substrate 210.

[0087] FIG. 11 is a drawing illustrating a light-emitting element according to still another embodiment. As shown in FIG. 11, a first electrode 220a, a light-emitting diode 100b, and a second electrode 230a can be sequentially arranged in the thickness direction of the substrate 210 on the substrate 210. The first electrode 220a, the light-emitting diode 100b, and the second electrode 230a are the same as those described above, and specific descriptions are omitted.

[0088] FIG. 12 is a drawing showing a light-emitting element according to still another embodiment. As shown in FIG. 12, the light-emitting element 200c may include a substrate 210, a light-emitting diode 100c, a first electrode 220b, and a second electrode 230b. The light-emitting diode 100c may include a first semiconductor layer 110a, a plurality of active elements 122 disposed apart from each other, and a second semiconductor layer 130. The first semiconductor layer 110a may include a first semiconductor common layer 112a and a plurality of first semiconductor elements 114. An insulating layer may be disposed between the plurality of active elements 122.

[0089] The first electrode 220b is disposed on the first semiconductor common layer 112a and on the same plane as the first semiconductor common layer 112a of the first semiconductor element 114. The second electrode 230b is also disposed on the second semiconductor layer 130.

[0090] The above-described light-emitting diodes 100, 100a, 100b, 100c are also used as light sources for various display devices. As an example, the light-emitting diodes 100, 100a, 100b, 100c are also applied to lighting devices and self-emitting display devices.

[0091] FIG. 13 is a circuit diagram showing a unit light-emitting region of a light-emitting device according to an embodiment. Referring to FIG. 13, the sub-pixel SP may include a light-emitting diode LD and a driving circuit C connected thereto for driving the light-emitting diode LD.

[0092] The first electrode (for example, an anode electrode) of the light-emitting diode LD is connected to the first power supply VDD via the driving circuit C, and the second electrode (for example, a cathode electrode) is connected to the second power supply VSS. The light-emitting diode can have the above-described structure.

[0093] The first power supply VDD and the second power supply VSS can have different potentials from each other. As an example, the second power supply VSS can have a potential lower than the potential of the first power supply VDD by at least the threshold voltage of the light-emitting diode LD.

[0094] The light-emitting diode LD can emit light with a luminance corresponding to the drive current controlled by the drive circuit C.

[0095] On the other hand, in FIG. 13, although an embodiment in which only one light-emitting diode LD is included in the sub-pixel SP is disclosed, it may include a plurality of light-emitting diodes connected in parallel to each other.

[0096] The drive circuit C may include a first transistor M1, a second transistor M2, and a storage capacitor C st However, the structure of the drive circuit C is not limited to the embodiment illustrated in FIG. 13.

[0097] The first electrode of the first transistor M1 (switching transistor) is connected to the data line D, and the second electrode is connected to the first node N1. Here, the first electrode and the second electrode of the first transistor M1 are different electrodes from each other. For example, if the first electrode is the source electrode, the second electrode is also the drain electrode. And the gate electrode of the first transistor M1 is connected to the scanning line S.

[0098] When such a first transistor M1 is supplied with a scanning signal having a voltage (for example, a low voltage) at which the first transistor M1 can be turned on from the scanning line S, it is turned on, and electrically connects the data line D and the first node N1. At this time, a data signal of the frame is supplied to the data line D, whereby the data signal is transmitted to the first node N1. The data signal transmitted to the first node N1 is charged in the storage capacitor C st

[0099] The first electrode of the second transistor M2 (drive transistor) is connected to the first power supply VDD, and the second electrode is connected to the first electrode of the light-emitting diode LD. The gate electrode of the second transistor M2 is connected to the first node N1. Such a second transistor M2 controls the amount of drive current supplied to the light-emitting diode LD corresponding to the voltage of the first node N1.​

[0100] Storage capacitor C st One electrode of the storage capacitor C is connected to the first power supply VDD, and the other electrode is connected to the first node N1. Such a storage capacitor C st charges the voltage corresponding to the data signal supplied to the first node N1 and maintains the charged voltage until the data signal of the next frame is supplied.

[0101] For the sake of convenience, in FIG. 13, a relatively simple-structured driving circuit C including a first transistor M1 for transmitting a data signal inside the sub-pixel SP, a storage capacitor C for storing the data signal st and a second transistor M2 for supplying a driving current corresponding to the data signal to the light-emitting diode LD is illustrated. However, the structure of the driving circuit C is not limited thereto and can be variously modified. For example, the driving circuit C may include transistor elements such as a transistor element for compensating the threshold voltage of the second transistor M2, a transistor element for initializing the first node N1, and / or a transistor element for controlling the light-emitting time of the light-emitting diode LD, and other circuit elements such as a boosting capacitor for boosting the voltage of the first node N1, which goes without saying.

[0102] Also, in FIG. 13, the transistors included in the driving circuit C, for example, the first transistor M1 and the second transistor M2 are illustrated as both P-type transistors, but the driving circuit C is not limited thereto. The first transistor M1 and / or the second transistor M2 included in the driving circuit C can also be changed to N-type transistors.

[0103] FIG. 14 is a drawing showing a part of a display device according to an embodiment. Referring to FIG. 14, the display device 1000 may include a substrate 410 provided with a plurality of pixels. One pixel may include a first sub-pixel SP1, a second sub-pixel SP2, and a third sub-pixel SP3 provided on the substrate 410.

[0104] The first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 are pixel regions for displaying an image in one pixel and are also light-emitting regions where light is emitted.

[0105] Each of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 may include a substrate 410, a driving element layer 420, a display element layer 430, and a cover structure layer 440.

[0106] The substrate 410 may include an insulating material such as glass, organic polymer, or crystal. Further, the substrate 410 may be made of a flexible material that can be warped or folded and can have a single-layer structure or a multi-layer structure.

[0107] The driving element layer 420 may include a buffer layer 421 disposed on the substrate 410, a transistor TFT disposed on the buffer layer 421, and a driving voltage wiring (not shown).

[0108] The buffer layer 421 can prevent impurities from diffusing into the transistor TFT. The buffer layer 421 may be provided as a single layer or as a multi-layer of at least a double layer or more.

[0109] When the buffer layer 421 is provided as a multi-layer, each layer may be formed of the same material or may also be formed of different materials from each other. The buffer layer 421 may also be omitted depending on the material of the substrate 410 and the process conditions.

[0110] The transistor TFT can drive the corresponding light-emitting diode among the plurality of light-emitting diodes LD1, LD2, LD3 included in the display element layer 430. The transistor TFT may include a semiconductor layer SC, a gate electrode G, a source electrode S, and a drain electrode D.

[0111] The semiconductor layer SC is also disposed on the buffer layer 421. The semiconductor layer SC may include a source region in contact with the source electrode S and a drain region in contact with the drain electrode D. The region between the source region and the drain region is also a channel region.

[0112] The semiconductor layer SC is also a semiconductor pattern made of polysilicon, amorphous silicon, an oxide semiconductor, etc. The channel region is a semiconductor pattern not doped with impurities and is also an intrinsic semiconductor. The source region and the drain region are also semiconductor patterns doped with impurities.

[0113] The gate electrode G is provided on the semiconductor layer SC with the gate insulating layer 422 interposed therebetween. Each of the source electrode S and the drain electrode D is also in contact with the source region and the drain region of the semiconductor layer SC through contact holes penetrating the interlayer insulating layer 423 and the gate insulating layer 422.

[0114] A protective layer 424 may be provided on the transistor TFT. The display element layer 430 may include a plurality of light-emitting diodes LD1, LD2, LD3 provided on the protective layer 424. For example, the light-emitting diode LD1 in the first sub-pixel SP1 emits red light, the light-emitting diode LD2 in the second sub-pixel SP2 emits green light, and the light-emitting diode LD3 in the third sub-pixel SP3 can emit blue light. By adjusting the In content in the manufacturing process of the light-emitting diodes LD1, LD2, LD3, the wavelengths of the emitted light become different.

[0115] In the drawings, as light-emitting diodes LD1, LD2, and LD3, the light-emitting diode 100b illustrated in FIG. 9 is shown. Different from that, any one of the light-emitting diodes LD1, LD2, and LD3 in the first sub-pixel PS1, the second sub-pixel PS2, and the third sub-pixel SP3 can have the structures of the light-emitting diodes 100, 100a, and 100c. For example, the light-emitting diode that emits red light is also the light-emitting diode 100, 100a, 100b, or 100c with the aforementioned structure, and for the light-emitting diode that emits green light and the light-emitting diode that emits blue light, light-emitting diodes with structures different from those of the light-emitting diodes 100, 100a, 100b, and 100c can be applied.

[0116] The display element layer 430 may further include a pixel definition film 431. The pixel definition film 431 is provided on the protective layer 424 and can partition the light-emitting regions in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 respectively. The pixel definition film 431 may include openings that expose the light-emitting diodes LD1, LD2, and LD3 included in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 respectively.

[0117] On the substrate 410, two adjacent pixel definition films 431 can be spaced apart by a certain distance. For example, two adjacent pixel definition films 431 can be spaced apart on the substrate 210 by a length equal to or greater than that of the light-emitting diodes LD1, LD2, and LD3. The pixel definition film 431 is also an insulating substance including an inorganic material or an organic material, but is not limited thereto.

[0118] The pixel definition film 431 is also an insulating substance including an organic material. For example, the pixel definition film 431 may include polystyrene, polymethyl methacrylate (PMMA), polyacrylonitrile (PAN), polyamide (PA), polyimide (PI), polyaryl ether (PAE), heterocyclic polymer, parylene, epoxy, benzocyclobutene (BCB), siloxane resin, silane resin, etc.

[0119] On the pixel definition film 431, a first insulating layer 432a can be provided. The first insulating layer 432a can cover a part of the upper surface of each of the light-emitting diodes LD1, LD2, and LD3 provided in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3, respectively. By the first insulating layer 432a, the first end portion and the second end portion of each of the light-emitting diodes LD1, LD2, and LD3 are exposed to the outside.

[0120] The first electrode E1 and the second electrode E2 are also disposed on the protective layer 424. The first electrode E1 may include a first sub-electrode EL1 disposed adjacent to one end (e.g., the first semiconductor layer) of the corresponding light-emitting diode LD, and a first contact electrode CNE1 that electrically connects the first sub-electrode EL1 and one end of the light-emitting diode LD. The second electrode E2 may include a second sub-electrode EL2 disposed adjacent to the other end (e.g., the second semiconductor layer) of the corresponding light-emitting diode LD, and a second contact electrode CNE2 that electrically connects the second sub-electrode EL2 and one end of the light-emitting diode LD.

[0121] Thereby, a driving voltage is applied to the corresponding light-emitting diode LD via the first electrode E1, and the voltage of the transistor TFT can be applied to the corresponding light-emitting diode LD via the second electrode E2. Eventually, by applying a predetermined voltage to both end portions of the light-emitting diode LD via the first electrode E1 and the second electrode E2, the light-emitting diode LD can emit light. The wavelength of the emitted light may vary depending on the In content of the light-emitting diode.

[0122] A second insulating layer 432b and a third insulating layer 432c can be provided on the first electrode E1 and the second electrode E2.

[0123] An overcoat layer 440 can be provided on the third insulating layer 432c. The overcoat layer 440 is also a planarization layer that relaxes the steps generated by the components disposed below it. Further, the overcoat layer 440 is also a sealing layer that prevents oxygen, moisture, etc. from penetrating into the light-emitting diode.

[0124] On the one hand, when the light-emitting diodes LD1, LD2, and LD3 of the respective sub-pixels SP1, SP2, and SP3 emit light of the same wavelength, the display device may further include a color conversion layer (not shown). The color conversion layer may include a first color conversion pattern to a third color conversion pattern. Here, each of the first color conversion pattern to the third color conversion pattern may correspond to each sub-pixel. For example, the first color conversion pattern may correspond to the first sub-pixel SP1, the second color conversion pattern may correspond to the second sub-pixel SP2, and the third color conversion pattern may correspond to the third sub-pixel SP3.

[0125] FIG. 15 is a drawing illustrating a part of a display device according to another embodiment. Comparing FIG. 14 and FIG. 15, the first semiconductor layer, the active layer, and the second semiconductor layer of the light-emitting diode LD illustrated in FIG. 15 may be arranged parallel to the thickness direction of the substrate 410.

[0126] FIG. 16 is a drawing illustrating a part of a display device according to still another embodiment. As illustrated in FIG. 16, a display element layer 430, a driving element layer 420, and an overcoat layer 440 may be sequentially arranged on the substrate 410. Comparing FIG. 15 and FIG. 16, the display element layer 430 is also disposed between the substrate 410 and the driving element layer 420. The display device of FIG. 16 can form the display element layer 430, the driving element layer 420, and the overcoat layer 440 monolithically and sequentially on the substrate 410, and thus the manufacturing process can be simplified. Further, the display device of FIG. 16 is also implemented as a backlight type by the fact that each of the light-emitting diodes LD emits light of a different wavelength from each other.

[0127] The display device including the aforementioned light-emitting diode can be adopted in various electronic devices. For example, the display device is also applicable to various wearable devices such as televisions, notebook computers, mobile phones, smartphones, smart pads (PDs), PMPs (portable multimedia players), PDAs (personal digital assistants), navigations, and smartwatches.

[0128] The aforementioned light-emitting diode, its manufacturing method, and the display device have been described with reference to the embodiments illustrated in the drawings, but they are merely exemplary, and those skilled in the art will understand that various modifications and other equivalent embodiments are possible therefrom. In the foregoing description, many matters have been specifically described, but they should be construed as examples of specific embodiments rather than as limiting the scope of the invention. The scope of rights is therefore determined not by the described embodiments, but by the technical idea described in the claims.

Industrial Applicability

[0129] The semiconductor light-emitting diode and its manufacturing method of the present invention can be effectively applied to, for example, the technical field related to displays.

Explanation of Reference Numerals

[0130] 100, 100a, 100b, 100c, 100d, LD Light-emitting diode 110 First semiconductor layer 112, 112a First semiconductor common layer 114 First semiconductor element 120 Active layer 122 Active element 130 Second semiconductor layer 132 Second semiconductor element 134 Second semiconductor common layer 140 Insulating layer 220 First electrode 230 Second electrode

Claims

1. a first semiconductor layer, a plurality of active elements arranged separately from each other on the first semiconductor layer, each having a width narrower than the width of the first semiconductor layer, and a second semiconductor layer disposed on the plurality of active elements, wherein each of the plurality of active elements In ｘ Ga １－ｘ containing N(0.3 ≤ x ≤ 0.5), has a width of 10 nm or more and 30 nm or less and is in a strained state and a binodal state, and is a semiconductor light-emitting diode.

2. Each of the plurality of active elements has one end in contact with the first semiconductor layer and the other end in contact with the second semiconductor layer. The semiconductor light-emitting diode according to claim 1.

3. The plurality of active elements are arranged in a direction parallel to the width direction of the first semiconductor layer. The semiconductor light-emitting diode according to claim 1 or 2.

4. The sum of the widths of the plurality of active elements is narrower than the width of the first semiconductor layer. The semiconductor light-emitting diode according to any one of claims 1 to 3.

5. The pitch between the plurality of active elements is 20 nm or more and 300 nm or less. The semiconductor light-emitting diode according to any one of claims 1 to 4.

6. The first semiconductor layer includes a plurality of first semiconductor elements that are arranged separately while being in contact with each of the plurality of active elements, and a first semiconductor common layer in contact with the plurality of first semiconductor elements. The semiconductor light-emitting diode according to any one of claims 1 to 5.

7. The plurality of first semiconductor elements and the first semiconductor common layer are formed of the same material. The semiconductor light-emitting diode according to claim 6.

8. The second semiconductor layer includes a plurality of second semiconductor elements that are arranged separately while being in contact with the plurality of active elements. The semiconductor light-emitting diode according to any one of claims 1 to 7.

9. The second semiconductor layer further includes a second semiconductor common layer in contact with each of the plurality of second semiconductor elements. The semiconductor light-emitting diode according to claim 8.

10. The semiconductor light-emitting diode according to any one of claims 1 to 9 further includes an insulating layer disposed between the plurality of active elements.

11. The insulating layer includes a mesh structure. The semiconductor light-emitting diode according to claim 10.

12. The In content of each of the plurality of active elements is 35% or more. The semiconductor light-emitting diode according to any one of claims 1 to 11.

13. Each of the plurality of active elements The semiconductor light-emitting diode according to any one of claims 1 to 12, which emits red light.

14. A substrate, A display element layer disposed on the substrate and including a plurality of light-emitting diodes, A driving element layer including a plurality of transistors electrically connected to the plurality of light-emitting diodes and driving the plurality of light-emitting diodes, At least one of the plurality of light-emitting diodes A first semiconductor layer and a second semiconductor layer disposed apart from each other, and a plurality of active elements disposed in a spaced-apart arrangement between the first semiconductor layer and the second semiconductor layer, each having a width narrower than the width of the first semiconductor layer, Each of the plurality of active elements In ｘ Ga １－ｘ containing N(0.3 ≤ x ≤ 0.5), A display device having a width of 10 nm or more and 30 nm or less and being in a strained state and a binodal state.

15. A first electrode in contact with the first semiconductor layer, A second electrode in contact with the second semiconductor layer, and the display device according to claim 14, further including the second electrode.

16. The display device according to claim 15, wherein the first electrode, the first semiconductor layer, the plurality of active elements, the second semiconductor layer, and the second electrode are sequentially arranged in one direction.

17. The display device according to claim 15, wherein the first electrode, the first semiconductor layer, the plurality of active elements, the second semiconductor layer, and the second electrode are arranged in a direction perpendicular to the thickness direction of the substrate.

18. The display device according to claim 15, wherein the first electrode, the first semiconductor layer, the plurality of active elements, the second semiconductor layer, and the second electrode are arranged in a direction parallel to the thickness direction of the substrate.

19. Each of the plurality of active elements One end is in contact with the first semiconductor layer, and the other end is in contact with the second semiconductor layer, and the display device according to any one of claims 14 to 18.

20. The first semiconductor layer A plurality of first semiconductor elements disposed in a spaced-apart manner while being in contact with each of the plurality of active elements, A first semiconductor common layer in contact with the plurality of first semiconductor elements, and the display device according to any one of claims 14 to 19.

21. The display device according to any one of claims 14 to 20, further including an insulating layer disposed between the plurality of active elements on the first semiconductor layer.

22. The insulating layer The display device according to claim 21, including a mesh structure.

23. Each of the plurality of active elements is A display device according to any one of claims 14 to 22, which emits red light.

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