Light-emitting element, method for manufacturing same, and display device including light-emitting element

Abstract

The present disclosure provides a light-emitting element, a method for manufacturing the same, and a display device including the light-emitting element. The light-emitting element has a shape extending in one direction and includes: a first semiconductor layer; a second semiconductor layer; an active layer disposed between the first semiconductor layer and the second semiconductor layer; a first electrode layer disposed on the other surface of the first semiconductor layer opposite to the one surface of the first semiconductor layer facing the active layer; a second electrode layer disposed on the other surface of the second semiconductor layer opposite to the one surface of the second semiconductor layer facing the active layer; and an insulating film surrounding at least a part of the side surfaces of the first electrode layer and the second electrode layer and the side surface of the active layer, wherein the insulating film includes a first region and a second region, and the thickness of the first region surrounding the side surface of the active layer is greater than the thickness of the second region surrounding the side surface of the first electrode layer.

Description

Technical Field

[0001] The present disclosure relates to a light-emitting element, a method of manufacturing the same, and a display device including the light-emitting element. Background Art

[0002] With the development of multimedia, the importance of display devices is increasing. Accordingly, various types of display devices such as organic light-emitting display (OLED) devices and liquid crystal display (LCD) devices are being used.

[0003] A display panel such as an OLED panel or an LCD panel is a device included in a display device to display an image. Among these display panels, a light-emitting display panel may be provided as a light-emitting element, and examples of a light-emitting diode (LED) include an organic LED using an organic material as a fluorescent material and an inorganic LED using an inorganic material as a fluorescent material. Summary of the Invention

[0004] Technical Problem

[0005] Aspects of the present disclosure provide a light-emitting element and a method of manufacturing the same, the light-emitting element including a plurality of electrode layers and an insulating film surrounding the electrode layers.

[0006] Aspects of the present disclosure also provide a display device including the light-emitting element and capable of displaying light of various colors.

[0007] It should be noted that aspects of the present disclosure are not limited thereto, and other aspects not mentioned herein will be apparent to those of ordinary skill in the art from the following description.

[0008] Technical Solution

[0009] According to an embodiment of the present disclosure, there is provided a light-emitting element having a shape extending in one direction, including: a first semiconductor layer and a second semiconductor layer; an active layer disposed between the first semiconductor layer and the second semiconductor layer; a first electrode layer disposed on another surface of the first semiconductor layer opposite to one surface of the first semiconductor layer facing the active layer; a second electrode layer disposed on another surface of the second semiconductor layer opposite to one surface of the second semiconductor layer facing the active layer; and an insulating film surrounding at least a part of side surfaces of the first electrode layer and the second electrode layer and a side surface of the active layer, wherein, in the insulating film, a thickness of a first region surrounding the side surface of the active layer is greater than a thickness of a second region surrounding the side surface of the first electrode layer.

[0010] The insulating film may include: a first surface extending in one direction; a second surface connected between the first surface and an end surface of the first electrode layer; and a third surface connected between the first surface and an end surface of the second electrode layer.

[0011] In a plan view, at least a portion of the second surface may have a curved shape.

[0012] The third surface may be formed as a flat surface and located in the same plane as one surface of the second electrode layer.

[0013] The distance between the active layer and the first electrode layer may be greater than the distance between the active layer and the second electrode layer.

[0014] In a plan view, the width of one surface of the first semiconductor layer may be greater than the width of the other surface of the first semiconductor layer.

[0015] The active layer may emit first light having a central wavelength band in the range of 450 nm to 495 nm.

[0016] The light-emitting element may further include: a third semiconductor layer disposed between the first semiconductor layer and the active layer; a fourth semiconductor layer disposed between the active layer and the second semiconductor layer; and a fifth semiconductor layer disposed between the fourth semiconductor layer and the second semiconductor layer.

[0017] The active layer may emit second light having a central wavelength band in the range of 620 nm to 750 nm.

[0018] According to an embodiment of the present disclosure, there is provided a method of manufacturing a light-emitting element, including: preparing a semiconductor structure formed on a bottom substrate, and forming a support layer on a first surface of the semiconductor structure to separate the semiconductor structure from the bottom substrate; forming a first electrode layer on a second surface of the semiconductor structure separated from the bottom substrate, and etching the first electrode layer and the semiconductor structure in a direction perpendicular to the support layer to form a semiconductor crystal; and forming an insulating film around a side surface of the semiconductor crystal, and separating the semiconductor crystal having the insulating film formed thereon from the support layer.

[0019] The semiconductor structure may include a first semiconductor layer, an active layer formed on the first semiconductor layer, a second semiconductor layer formed on the active layer, and a second electrode layer formed on the second semiconductor layer, and the first surface may be a top surface of the second electrode layer.

[0020] The bottom substrate may include a base substrate and a separation layer formed on the base substrate, and separating the semiconductor structure may include separating the semiconductor structure from the base substrate by removing the separation layer.

[0021] The second surface of the semiconductor structure may be a bottom surface of the first semiconductor layer, and forming the semiconductor crystal may include etching the semiconductor structure in a direction from a bottom surface of the first electrode layer to a top surface of the second electrode layer.

[0022] Forming the insulating film may include: forming an insulating coating film around an outer surface of the semiconductor crystal; and removing the insulating coating film to expose a bottom surface of the first electrode layer.

[0023] The insulating film may include a first surface extending in one direction, a second surface located between the first surface and an end surface of the first electrode layer, and a third surface located between the first surface and an end surface of the second electrode layer, and at least a part of the second surface may have a curved shape.

[0024] According to an embodiment of the present disclosure, a display device including a first pixel and a second pixel is provided, which includes: a substrate; a first electrode provided on the substrate; a second electrode provided on the substrate and spaced apart from the first electrode; and at least one light-emitting element provided between the first electrode and the second electrode, wherein the light-emitting element includes: a first semiconductor layer and a second semiconductor layer; an active layer provided between the first semiconductor layer and the second semiconductor layer; a first electrode layer provided on another surface of the first semiconductor layer opposite to one surface of the first semiconductor layer facing the active layer; a second electrode layer provided on another surface of the second semiconductor layer opposite to one surface of the second semiconductor layer facing the active layer; and an insulating film surrounding at least a part of side surfaces of the first electrode layer and the second electrode layer and a side surface of the active layer, wherein, in the insulating film, a thickness of a first region surrounding the side surface of the active layer is greater than a thickness of a second region surrounding the side surface of the first electrode layer.

[0025] The insulating film may include a first surface extending in one direction, a second surface located between the first surface and an end surface of the first electrode layer, and a third surface located between the first surface and an end surface of the second electrode layer, and at least a part of the second surface may have a curved shape.

[0026] The display device may further include: a first contact electrode in contact with the first electrode and the second electrode layer; and a second contact electrode in contact with the second electrode and the first electrode layer.

[0027] The light-emitting element may include: a first light-emitting element provided in the first pixel; and a second light-emitting element provided in the second pixel, and the active layer of the first light-emitting element may emit first light having a center wavelength band in a range of 450 nm to 495 nm.

[0028] The second light-emitting element may further include a third semiconductor layer provided between the first semiconductor layer and the active layer, a fourth semiconductor layer provided between the active layer and the second semiconductor layer, and a fifth semiconductor layer provided between the fourth semiconductor layer and the second semiconductor layer, and the active layer of the second light-emitting element may emit second light having a center wavelength band in a range of 620 nm to 750 nm.

[0029] Details of other embodiments are included in the detailed description and the drawings.

[0030] Advantageous Effects

[0031] In a method of manufacturing a light-emitting element according to an embodiment, a light-emitting element having a first electrode layer and a second electrode layer may be manufactured by performing two separation steps and one etching step. The light-emitting element may include an insulating film surrounding the first electrode layer and the second electrode layer, and the insulating film surrounding the side surface of the first electrode layer may have a partially curved surface.

[0032] In a method of manufacturing a light-emitting element according to an embodiment, although the light-emitting element is manufactured through an etching process of etching semiconductor layers stacked on each other, the electrode layer may be protected by forming an insulating film surrounding the electrode layer.

[0033] The effects according to the embodiments are not limited to those exemplified above, and more different effects are included in the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic diagram of a light-emitting element according to an embodiment.

[0035] Figure 2 is along Figure 1 a cross-sectional view of the light-emitting element taken along line II-II'.

[0036] Figure 3 is a flowchart showing a method of manufacturing a light-emitting element according to an embodiment.

[0037] Figures 4 to 14 is a schematic diagram showing a method of manufacturing a light-emitting element according to an embodiment.

[0038] Figure 15 is a cross-sectional view of a light-emitting element according to another embodiment.

[0039] Figure 16 is Figure 15 an enlarged view of part Q of

[0040] Figure 17 is a cross-sectional view of a light-emitting element according to still another embodiment.

[0041] Figure 18 is a schematic diagram showing a light-emitting element according to another embodiment.

[0042] Figure 19 is along Figure 18 a cross-sectional view of the light-emitting element taken along line III-III'.

[0043] Figure 20 is a schematic plan view of a display device according to one embodiment.

[0044] Figure 21 is a schematic plan view of a pixel of a display device according to one embodiment.

[0045] Figure 22 is along Figure 21 Cross-sectional views taken along lines Xa-Xa', Xb-Xb' and Xc-Xc'.

[0046] Figure 23 is a cross-sectional view of a display device according to another embodiment.

[0047] Figure 24 is a plan view showing a pixel of a display device according to yet another embodiment. Detailed Embodiments

[0048] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. However, the invention may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0049] It will also be understood that when a layer is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Throughout the specification, the same reference numerals indicate the same components.

[0050] It will be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the teachings of the present invention, the first element discussed below may be referred to as the second element. Similarly, the second element may also be referred to as the first element.

[0051] Hereinafter, embodiments will be described with reference to the accompanying drawings.

[0052] Figure 1 is a schematic diagram of a light-emitting element according to one embodiment. Figure 2 is along Figure 1 Cross-sectional view of the light-emitting element taken along line II-II'.

[0053] The light-emitting element 300 may be a light-emitting diode. Specifically, the light-emitting element 300 may be an inorganic light-emitting diode having a micron or nanometer size and made of an inorganic material. When an electric field is formed between two electrodes facing each other in a specific direction, the inorganic light-emitting diode may be aligned between the two electrodes having polarity. The light-emitting element 300 may be aligned between the two electrodes by the electric field generated between the electrodes.

[0054] The light-emitting element 300 may have a shape extending in one direction. The light-emitting element 300 may have a shape such as a rod, a wire, a tube, etc. In an embodiment, the light-emitting element 300 may have a cylindrical or rod shape. However, the shape of the light-emitting element 300 is not limited thereto, and the light-emitting element 300 may have a polygonal column shape such as a cube, a cuboid, and a hexagonal prism, or may have various shapes such as a shape extending in one direction and having a partially inclined outer surface. A plurality of semiconductors included in the light-emitting element 300 to be described later may have a structure in which they are arranged or stacked in sequence along one direction.

[0055] The light-emitting element 300 may include a semiconductor layer doped with impurities of any conduction type (e.g., p-type or n-type). The semiconductor layer may emit light in a specific wavelength band by receiving an electric signal applied from an external power source.

[0056] The light-emitting element 300 according to one embodiment may emit light in a specific wavelength band. In an embodiment, the active layer 360 may emit blue light having a central wavelength band in the range from 450 nm to 495 nm. However, it should be understood that the central wavelength band of the blue light is not limited to the above range, but includes all wavelength ranges that can be considered blue in the related art. In addition, the light emitted from the active layer 360 of the light-emitting element 300 is not limited thereto, and may be green light having a central wavelength band in the range from 495 nm to 570 nm, or red light having a central wavelength band in the range from 620 nm to 750 nm. Hereinafter, the description will be made on the assumption that the light-emitting element 300 emits blue light, for example.

[0057] Refer to Figure 1 and Figure 2 , the light-emitting element 300 according to one embodiment may include a first semiconductor layer 310, a second semiconductor layer 320, an active layer 360, a first electrode layer 371, a second electrode layer 372, and an insulating film 380.

[0058] For example, the first semiconductor layer 310 may be an n-type semiconductor having a first conduction type. For example, when the light-emitting element 300 emits light in a blue wavelength band, the first semiconductor layer 310 may include having the chemical formula Al x Ga y In1-x-y A semiconductor material of N(0≤x≤1, 0≤y≤1, 0≤x + y≤1). For example, it can be any one or more of n-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The first semiconductor layer 310 can be doped with a first conductive dopant. For example, the first conductive dopant can be Si, Ge, Se, Sn, etc. In an embodiment, the first semiconductor layer 310 can be n-GaN doped with n-type Si. The length of the first semiconductor layer 310 can have a range of 1.5 μm to 5 μm, but is not limited thereto.

[0059] The second semiconductor layer 320 is disposed on the active layer 360 to be described later. As a non-limiting example, the second semiconductor layer 320 can be a p-type semiconductor having a second conductive type. For example, when the light-emitting element 300 emits light in the blue or green wavelength band, the second semiconductor layer 320 can include a chemical formula Al x Ga y In 1-x-y A semiconductor material of N(0≤x≤1, 0≤y≤1, 0≤x + y≤1). For example, it can be any one or more of p-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The second semiconductor layer 320 can be doped with a second conductive dopant. For example, the second conductive dopant can be Mg, Zn, Ca, Ba, etc. In an embodiment, the second semiconductor layer 320 can be p-GaN doped with p-type Mg. The length of the second semiconductor layer 320 can have a range of 0.05 μm to 0.10 μm, but is not limited thereto.

[0060] Meanwhile, although the first semiconductor layer 310 and the second semiconductor layer 320 are shown as a single layer in the drawings, the present disclosure is not limited thereto. According to some embodiments, depending on the material of the active layer 360, the first semiconductor layer 310 and the second semiconductor layer 320 can also include a greater number of layers such as a cladding layer or a tensile strain barrier reduction (TSBR) layer. A description thereof will be given later with reference to other drawings.

[0061] The active layer 360 is disposed between the first semiconductor layer 310 and the second semiconductor layer 320. The active layer 360 may include a material having a single quantum well structure or a multi-quantum well structure. When the active layer 360 includes a material having a multi-quantum well structure, a plurality of quantum layers and well layers may be alternately stacked. The active layer 360 may emit light by coupling electron-hole pairs according to an electrical signal applied via the first semiconductor layer 310 and the second semiconductor layer 320. For example, when the active layer 360 emits light in the blue wavelength band, it may include a material such as AlGaN or AlGaInN. In particular, when the active layer 360 has a structure in which quantum layers and well layers are alternately stacked into a multi-quantum well structure, the quantum layer may include a material such as AlGaN or AlGaInN, and the well layer may include a material such as GaN or AlInN. In an embodiment, as described above, the active layer 360 includes AlGaInN as the quantum layer and includes AlInN as the well layer, and the active layer 360 may emit blue light having a central wavelength band of 450 nm to 495 nm.

[0062] However, the present disclosure is not limited thereto, and the active layer 360 may have a structure in which a semiconductor material having a large energy band gap and a semiconductor material having a small band gap energy are alternately stacked, and may include other group III-V semiconductor materials according to the wavelength band of the emitted light. The light emitted from the active layer 360 is not limited to light in the blue wavelength band, and in some cases, the active layer 360 may also emit light in the red or green wavelength band. The length of the active layer 360 may have a range of 0.05 μm to 0.10 μm, but is not limited thereto.

[0063] Meanwhile, the light emitted from the active layer 360 may be emitted to the outer surface and both end faces of the light-emitting element 300 in the longitudinal direction. The directivity of the light emitted from the active layer 360 is not limited to one direction.

[0064] The electrode layer 370 may be an ohmic contact electrode. However, the present disclosure is not limited thereto, and the electrode layer 370 may be a Schottky contact electrode. The electrode layer 370 includes a first electrode layer 371 and a second electrode layer 372. The first electrode layer 371 is disposed on the bottom surface of the first semiconductor layer 310, and the second electrode layer 372 is disposed on the top surface of the second semiconductor layer 320.

[0065] When the light-emitting element 300 is in a display device 10 according to an embodiment as described later (see Figure 20)When the middle electrode is connected to the electrode or the contact electrode, the electrode layer 370 can reduce the resistance between the light-emitting element 300 and the electrode or the contact electrode. The electrode layer 370 may include a conductive metal. For example, the electrode layer 370 may include at least one of aluminum (Al), titanium (Ti), indium (In), gold (Au), silver (Ag), indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO). In addition, the electrode layer 370 may include an n-type or p-type doped semiconductor material. The electrode layer 370 may include the same material or different materials, but is not limited thereto.

[0066] The insulating film 380 is disposed to surround the outer surfaces of the semiconductor structure and the electrode layer 370 described above, wherein the semiconductor structure includes a first semiconductor layer 310, a second semiconductor layer 320, and an active layer 360. In an embodiment, the insulating film 380 may be disposed to surround at least the outer surface of the active layer 360 and extend along the extending direction of the light-emitting element 300. The insulating film 380 may function as a protective member. For example, the insulating film 380 may be formed to surround the side surfaces of the member to expose both ends of the light-emitting element 300 in the longitudinal direction.

[0067] In the drawings, although the insulating film 380 is shown as extending in the length direction of the light-emitting element 300 to cover the side surfaces in the range from the first electrode layer 371 to the second electrode layer 372, the present disclosure is not limited thereto. The insulating film 380 may only cover the outer surface of the portion of the semiconductor structure including the active layer 360, or may only cover a part of the outer surfaces of the first electrode layer 371 and the second electrode layer 372 to partially expose the outer surface of each electrode layer 370. However, here, since the insulating film 380 is formed to surround the first electrode layer 371 and the second electrode layer 372 after the formation of the first electrode layer 371 and the second electrode layer 372 in the manufacturing process of the light-emitting element 300 to be described later, the insulating film 380 according to an embodiment may be provided to surround the outer side surfaces of the first electrode layer 371 and the second electrode layer 372 of the light-emitting element 300.

[0068] In addition, in some embodiments, the insulating film 380 may be formed to have a partially rounded portion in a region adjacent to at least one end of the light-emitting element 300, for example, in a region surrounding the first electrode layer 371. The partially rounded portion may be formed as the insulating film 380 is partially etched during the manufacturing process of the light-emitting element 300. A detailed description thereof will be given later with reference to other drawings.

[0069] The thickness of the insulating film 380 may range from 10 nm to 1.0 μm, but is not limited thereto. Preferably, the thickness of the insulating film 380 may be about 40 nm.

[0070] The insulating film 380 may include a material having insulating properties, such as silicon oxide (SiO x ), silicon nitride (SiN x ), silicon oxynitride (SiO x N y ), aluminum nitride (AlN), aluminum oxide (Al2O3), etc. Thus, an electrical short circuit that may occur when the active layer 360 is in direct contact with the electrode (electrical signals are transmitted to the light-emitting element 300 through the electrode) can be prevented. In addition, since the insulating film 380 protects the outer surface of the light-emitting element 300 including the active layer 360, a reduction in light-emitting efficiency can be prevented.

[0071] In addition, in some embodiments, the insulating film 380 may have a surface-treated outer surface. When manufacturing the display device 10, the light-emitting element 300 may be aligned by being ejected in a state of being dispersed in a predetermined ink onto the electrode. Here, the surface of the insulating film 380 may be treated to be hydrophobic or hydrophilic so as to keep the light-emitting element 300 in a dispersed state without aggregating with other adjacent light-emitting elements 300 in the ink.

[0072] The light-emitting element 300 may have a length h of 1 μm to 10 μm, or 2 μm to 6 μm, preferably 3 μm to 5 μm. In addition, the diameter of the light-emitting element 300 may be in the range of 300 nm to 700 nm, and the aspect ratio of the light-emitting element 300 may be 1.2 to 100. However, the present disclosure is not limited thereto, and the plurality of light-emitting elements 300 included in the display device 10 may have different diameters according to the composition of the active layer 360. Preferably, the diameter of the light-emitting element 300 may be about 500 nm.

[0073] The light-emitting element 300 may be manufactured by epitaxial growth to grow a semiconductor crystal. The light-emitting element 300 may be manufactured by sequentially growing a first semiconductor layer 310, an active layer 360, and a second semiconductor layer 320 on a bottom substrate. However, here, since the first semiconductor layer 310 does not grow on the first electrode layer 371 provided on its bottom surface, the first electrode layer 371 may be formed on the bottom surface of the first semiconductor layer 310 after the semiconductor structure is grown. According to one embodiment, a manufacturing method for the light-emitting element 300 may include the following processes: forming a semiconductor structure, separating the semiconductor structure from the bottom substrate, and forming the first electrode layer 371. The light-emitting element 300 may be manufactured by performing at least two separation processes of separating the grown semiconductor structure from the bottom substrate.

[0074] Hereinafter, a method for manufacturing the light-emitting element 300 according to one embodiment will be described.

[0075] Figure 3is a flowchart showing a method of manufacturing a light-emitting element according to an embodiment. Figures 4 to 14 is a schematic diagram showing a method of manufacturing a light-emitting element according to an embodiment.

[0076] A method of manufacturing a light-emitting element 300 according to an embodiment may include: a first separation step of separating a semiconductor structure 3000 (see Figure 5 ) formed on a bottom substrate 2000 (see Figure 5 ); an etching step of forming a first electrode material layer on one surface of the semiconductor structure 3000 and etching the first electrode material layer in one direction; and a second separation step of separating a semiconductor rod ROD (see Figure 6 ) including a plurality of semiconductor layers 310 and 320, an active layer 360, an electrode layer 370, and an insulating film 380 from a support layer 5200 (see Figure 13 ). The light-emitting element 300 having a structure in which a plurality of layers are stacked on one another may be manufactured by sequentially stacking a first semiconductor layer 310, an active layer 360, a second semiconductor layer 320, and the like. However, here, the order of stacking the plurality of layers may be different from the foregoing example, and the first electrode layer 371 provided on the bottom surface of the first semiconductor layer 310 may be formed later than the second electrode layer 372. A method of manufacturing a light-emitting element 300 according to an embodiment may include: a first separation step of forming and separating a semiconductor structure 3000; an etching step of etching the semiconductor structure 3000; and a second separation step of separating the semiconductor rod ROD formed through these processes.

[0077] As Figure 3 shown, a method of manufacturing a light-emitting element 300 according to an embodiment includes: preparing a semiconductor structure formed on a bottom substrate (S100); forming a support layer on the semiconductor structure and separating the semiconductor structure from the bottom substrate (S200); forming a first electrode layer on the separation surface of the semiconductor structure (S300); etching the semiconductor structure to form a semiconductor crystal (step S400); and forming an insulating film surrounding the semiconductor crystal and separating the semiconductor crystal from the support layer (S500).

[0078] A method of manufacturing a light-emitting element 300 according to an embodiment will be described in detail. First, as Figure 4 shown, a bottom substrate 2000 is prepared. The bottom substrate 2000 includes a base substrate 2100, a buffer material layer 2200 formed on the base substrate 2100, and a separation layer 2300 formed on the buffer material layer 2200. The bottom substrate 2000 may have a structure in which the base substrate 2100, the buffer material layer 2200, and the separation layer 2300 are sequentially stacked.

[0079] The base substrate 2100 may include a transparent substrate such as a sapphire (Al2O3) substrate and a glass substrate. However, the present disclosure is not limited thereto, and the base substrate 2100 may be formed of a conductive substrate such as GaN, SiC, ZnO, Si, GaP, and GaAs. The following description is for the case where the base substrate 2100 is a sapphire (Al2O3) substrate. Although not limited, the base substrate 2100 may have a thickness, for example, in the range of 400 μm to 1500 μm.

[0080] A semiconductor structure is formed on the underlying substrate 2000. The semiconductor structure grown by an epitaxial method may be formed by growing a seed crystal. Here, one of electron beam deposition, physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma laser deposition (PLD), dual-type thermal evaporation, sputtering, and metalorganic chemical vapor deposition (MOCVD) may be used, and preferably metalorganic chemical vapor deposition (MOCVD) is used to form the semiconductor structure. However, the present disclosure is not limited thereto.

[0081] Generally, the precursor material for forming the semiconductor structure may be selected within a generally selectable range to form the target material without any limitation. For example, the precursor material may be a metal precursor including an alkyl group such as a methyl group or an ethyl group. Examples of the precursor material may include, but are not limited to, trimethylgallium (Ga(CH3)3), trimethylaluminum (Al(CH3)3), and triethyl phosphate ((C2H5)3PO4). Hereinafter, without describing the method and processing conditions for forming the semiconductor structure, the processing sequence of the method for manufacturing the light-emitting element 300 and the layered structure of the light-emitting element 300 will be described in detail.

[0082] A buffer material layer 2200 is formed on the base substrate 2100. Although one buffer material layer 2200 is shown deposited in the drawings, the present disclosure is not limited thereto, and a plurality of layers may be formed. The buffer material layer 2200 may be provided to reduce the lattice constant difference between the first semiconductor layer 3100 (see Figure 5 ) and the base substrate 2100.

[0083] For example, the buffer material layer 2200 may include an undoped semiconductor and may be a material that includes substantially the same material as the first semiconductor layer 3100 and is neither n-type doped nor p-type doped. In an embodiment, the buffer material layer 2200 may be, but is not limited to, at least one of undoped InAlGaN, GaN, AlGaN, InGaN, AlN, and InN. The buffer material layer 2200 may also be omitted depending on the base substrate 2100. An example of forming the buffer material layer 2200 including an undoped semiconductor on the base substrate 2100 will be described below.

[0084] The separation layer 2300 may be disposed on the buffer material layer 2200. The separation layer 2300 may include a material that enables the crystal of the first semiconductor layer 3100 to grow smoothly. The separation layer 2300 may include at least one of an insulating material and a conductive material. As an example, the separation layer 2300 may include silicon oxide (SiO x ), silicon nitride (SiN x ), silicon oxynitride (SiO x N y ) etc. as the insulating material, and may include ITO, IZO, IGO, ZnO, graphene, graphene oxide etc. as the conductive material. However, it is not limited thereto.

[0085] The separation layer 2300 may be removed in a process to be described later, and thus, the semiconductor structure 3000 formed on the separation layer 2300 may be separated from the underlying substrate 2000. The removal of the separation layer 2300 may be accomplished by a chemical lift-off (CLO) method, and thus, the bottom surface of the first semiconductor layer 3100 may be flat, the same as the surface of the separation layer 2300.

[0086] Next, as shown in Figure 5 , a semiconductor structure 3000 is formed on the underlying substrate 2000. The semiconductor structure 3000 includes a first semiconductor layer 3100, an active layer 3600, a second semiconductor layer 3200, and a second electrode material layer 3720, and the semiconductor structure 3000 may be formed on the separation layer 2300. The plurality of material layers included in the semiconductor structure 3000 may be formed by performing a typical process as described above, and the plurality of layers included in the semiconductor structure 3000 may correspond to the corresponding layers included in the light-emitting element 300 according to an embodiment. That is, the plurality of material layers may include the same materials as the first semiconductor layer 310, the active layer 360, the second semiconductor layer 320, and the second electrode layer 372 of the light-emitting element 300. However, here, Figure 5 the semiconductor structure 3000 may not have a layer corresponding to the first electrode layer 371 of the light-emitting element 300.

[0087] According to an embodiment, the first electrode layer 371 of the light-emitting element 300 may be formed after exposing one surface of the first semiconductor layer 3100 by performing a first separation step of separating the semiconductor structure 3000 from the underlying substrate 2000.

[0088] Then, a first separation step of separating the semiconductor structure 3000 from the underlying substrate 2000 is performed, and a first electrode material layer 3710 is formed on one surface of the first semiconductor layer 3100 separated from the underlying substrate 2000 (see Figure 8)。According to one embodiment, forming the first electrode material layer 3710 may include: a process of forming an adhesive layer 5100 and a support layer 5200 on the semiconductor structure 3000; and a process of removing the separation layer 2300 of the underlying substrate 2000 to separate the semiconductor structure 3000 from the underlying substrate 2000 and form the first electrode material layer 3710 on one surface of the first semiconductor layer 3100.

[0089] Referring to Figure 6 , an adhesive layer 5100 and a support layer 5200 are formed on the semiconductor structure 3000. The adhesive layer 5100 is formed on the top surface of the semiconductor structure 3000, that is, on top of the second electrode material layer 3720, and the support layer 5200 is formed on the top surface of the adhesive layer 5100. When the semiconductor structure 3000 is separated in a subsequent process, the support layer 5200 can serve to support the semiconductor structure 3000. The adhesive layer 5100 can fix the semiconductor structure 3000 to the support layer 5200. As will be described later, the semiconductor structure 3000 can be formed as semiconductor rods ROD on the adhesive layer 5100, and the semiconductor rods ROD can be formed as light-emitting elements 300 as they are separated from the adhesive layer 5100 physically or chemically.

[0090] The support layer 5200 can perform the same functions as the base substrate 2100 in an etching step and a second separation step, where the etching step and the second separation step are performed after the first separation step. The support layer 5200 can include a material having a higher strength than the adhesive layer 5100, and in some embodiments, the support layer 5200 can be implemented by but not limited to a thermal release tape (TRT), polyethylene terephthalate (PET), a plastic film, etc. However, the present disclosure is not limited thereto.

[0091] The adhesive layer 5100 can be used to fix the semiconductor structure 3000 or the semiconductor rods ROD to the support layer 5200. The adhesive layer 5100 can include an organic material having an adhesive strength, and in some embodiments, the adhesive layer 5100 can include at least one of polymethyl methacrylate (PMMA), photoresist (PR), and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). However, it is not limited thereto.

[0092] The first separation step can be performed after the adhesive layer 5100 and the support layer 5200 provided on the semiconductor structure 3000 are formed, and then the etching step and the second separation step can be performed.

[0093] As Figure 7As depicted, a first separation step of removing the separation layer 2300 to separate the semiconductor structure 3000 from the underlying substrate 2000 is performed. The removal of the separation layer 2300 can be accomplished by a chemical lift-off (CLO) method. In some embodiments, the separation layer 2300 can be removed by a wet etching process using a separation etchant (e.g., buffered oxide etchant (BOE) or hydrofluoric acid (HF)), but is not limited thereto.

[0094] The semiconductor structure 3000 can be separated from the underlying substrate 2000 as the separation layer 2300 is removed and can be formed on the support layer 5200 with an adhesive layer 5100 therebetween. In the separated semiconductor structure 3000, the second electrode material layer 3720, the second semiconductor layer 3200, the active layer 3600, and the first semiconductor layer 3100 are arranged in sequence from the top surface of the support layer 5200, and one surface of the first semiconductor layer 3100, i.e., the separation surface of the first semiconductor layer 3100 separated from the underlying substrate 2000, can be exposed.

[0095] Subsequently, as Figure 8 shown, a first electrode material layer 3710 is formed on the separation surface (which is one surface of the first semiconductor layer 3100 of the semiconductor structure 3000). The first electrode material layer 3710 can be formed in the same manner as the aforementioned second electrode material layer 3720. The first electrode material layer 3710 can correspond to the first electrode layer 371 of the light-emitting element 300 and can include the same material as the first electrode layer 371. The light-emitting element 300 can be manufactured by sequentially stacking multiple layers including the semiconductor layers 3100 and 3200 and the active layer 3600 by an epitaxial growth method starting from the first semiconductor layer 3100. However, here, the first electrode layer 371 provided on the bottom surface of the first semiconductor layer 3100 can be formed after separating the semiconductor structure 3000 from the underlying substrate 2000 after forming the second electrode material layer 3720. That is, the method of manufacturing the light-emitting element 300 according to one embodiment can include: sequentially forming multiple layers stacked from the first semiconductor layer 3100; and forming the first electrode layer 371 after forming the second electrode layer 372.

[0096] Thereafter, the semiconductor crystal 3000' is formed by etching the semiconductor structure 3000 having the first electrode material layer 3710 thereon in a direction perpendicular to the support layer 5200 (see Figure 11)。The light-emitting element 300 may have a shape extending in one direction, and the semiconductor structure 3000 may be etched in the one direction to form the semiconductor crystal 3000'. Forming the semiconductor crystal 3000' may include typical etching processes. In some embodiments, forming the semiconductor crystal 3000' may include: forming an etching mask layer 1600 and an etching pattern layer 1700 on the semiconductor structure 3000 (see Figure 9 ); etching the semiconductor structure 3000 according to the pattern of the etching pattern layer 1700; and removing the etching mask layer 1600 and the etching pattern layer 1700.

[0097] Referring to Figure 9 , an etching mask layer 1600 is formed on the first electrode material layer 3710, and an etching pattern layer 1700 is formed on the etching mask layer 1600. The etching mask layer 1600 may be used as a mask for successively etching multiple layers of the semiconductor structure 3000. The etching mask layer 1600 may include a first etching mask layer 1610 containing an insulating material and a second etching mask layer 1620 containing a metal.

[0098] The first etching mask layer 1610 may include an oxide or a nitride as the insulating material. Examples of the insulating material may include silicon oxide (SiO x ), silicon nitride (SiN x ), and silicon oxynitride (SiO x N y ). The first etching mask layer 1610 may have a thickness in the range of 0.5 μm to 1.5 μm, but is not limited thereto.

[0099] The second etching mask layer 1620 is disposed on the first etching mask layer 1610. For example, the second etching mask layer 1620 may be a hard mask layer. The second etching mask layer 1620 may include a material capable of acting as a mask for successive etching of the semiconductor structure 3000. For example, it may include a metal such as but not limited to chromium (Cr). The second etching mask layer 1620 may have a thickness in the range of 30 nm to 150 nm, but is not limited thereto.

[0100] The etching pattern layer 1700 may be disposed on the etching mask layer 1600. The etching pattern layer 1700 includes one or more patterns spaced apart from each other and may be used as a mask for successive etching of the semiconductor structure 3000. The etching pattern layer 1700 may include a polymer, polystyrene spheres, silica spheres, etc., but the material of the etching pattern layer 1700 is not particularly limited as long as the material is suitable for forming a pattern.

[0101] For example, in the case where the etch pattern layer 1700 includes a polymer, a conventional method of forming a pattern using the polymer can be employed. For example, methods such as photolithography, electron beam lithography, and nanoimprint lithography can be used to form the etch pattern layer 1700 including the polymer.

[0102] In an embodiment, the etch pattern layer 1700 can be formed by nanoimprint lithography, and the nano pattern of the etch pattern layer 1700 can include a nanoimprint resin. The resin can include a fluorinated monomer, an acrylate monomer, dipentaerythritol hexaacrylate, dipropylene glycol diacrylate, poly(ethylene glycol) phenyl ether acrylate, butylated hydroxytoluene (BHT), 1-hydroxycyclohexyl phenyl ketone (Irgacure 184), etc., but is not limited thereto.

[0103] Thereafter, as Figure 10 and Figure 11 shown in, the semiconductor structure 3000 is etched according to the etch pattern layer 1700 to form a semiconductor crystal 3000'. A method of manufacturing a light-emitting element 300 according to one embodiment can include: etching the semiconductor structure 3000 starting from the bottom surface (corresponding to the Figures 8 to 10 upper surface in) of the first electrode material layer 3710 in a direction perpendicular to the support layer 5200. Since the semiconductor crystal 3000' is formed by etching the semiconductor structure 3000 having the first electrode material layer 3710 thereon in this one direction, the insulating coating film 3800 (see Figure 12 ) formed to surround the outer surface of the semiconductor crystal 3000' described later can also be formed on the outer surface of the first electrode layer 371. Therefore, the insulating film 380 of the light-emitting element 300 can also be formed on the outer side surface of the first electrode layer 371.

[0104] Meanwhile, the light-emitting element 300 can be formed by etching the semiconductor structure 3000 in a direction opposite to the direction in which the first electrode material layer 3710, the first semiconductor layer 3100, and the active layer 3600 are sequentially arranged. In some embodiments, the diameter of the semiconductor crystal 3000' can vary depending on the direction in which the semiconductor structure 3000 is etched. That is, referring to Figure 8 , when the semiconductor structure 3000 is etched from the bottom surface of the first electrode material layer 3710 in a direction perpendicular to the support layer 5200, the diameter of the semiconductor crystal 3000' can increase as it proceeds toward the second electrode material layer 3720 located on the lower side. A description thereof will be given later with reference to other drawings.

[0105] Forming the semiconductor crystal 3000' may include: a first etching step of forming a first etching hole h1 by etching the etching mask layer 1600 and the first electrode material layer 3710 in a direction perpendicular to the support layer 5200 along the gaps between the patterns of the etching pattern layer 1700; a step of removing the etching pattern layer 1700; a second etching step of forming a second etching hole h2 by etching a plurality of layers from the first semiconductor layer 3100 to the second electrode material layer 3720 along the first etching hole h1; and a step of removing the etching mask layer 1600.

[0106] Etching of the semiconductor structure 3000 can be achieved by typical methods. For example, the etching process can be performed using dry etching, wet etching, reactive ion etching (RIE), inductively coupled plasma reactive ion etching (ICP-RIE), etc. Dry etching may be suitable for vertical etching because it can achieve anisotropic etching. In the case of using the foregoing etching techniques, Cl2 or O2 can be used as the etchant. However, it is not limited thereto.

[0107] In some embodiments, a combination of dry etching and wet etching can be used to etch the semiconductor structure 3000. For example, dry etching can be performed in the depth direction, and then wet etching can be performed for anisotropic etching such that the etched sidewalls are placed in a plane perpendicular to the surface.

[0108] Referring to Figure 10 and Figure 11 , the first etching step of etching the etching mask layer 1600 and the first electrode material layer 3710 along the gaps between the patterns of the etching pattern layer 1700 to form the first etching hole h1 is performed. The first etching hole h1 is formed as the etching pattern layer 1700, the etching mask layer 1600, and the first electrode material layer 3710 are removed. The first etching hole h1 exposes the separation surface of the first semiconductor layer 3100 therethrough. Next, the second etching step of etching a plurality of layers from the first semiconductor layer 3100 to the second electrode material layer 3720 along the first etching hole h1 to form the second etching hole h2 is performed. In the drawings, although the first etching step and the second etching step are shown as separate processes, the present disclosure is not limited thereto. The first etching step and the second etching step can be continuously performed in a single process. The semiconductor crystal 3000' formed by etching the semiconductor structure 3000 may include, in the same manner as the light-emitting element 300 according to one embodiment, a first electrode layer 371, a first semiconductor layer 310, an active layer 360, a second semiconductor layer 320, and a second electrode layer 372.

[0109] Then, the semiconductor crystal 3000' is formed by removing the etching mask layer 1600 and the etching pattern layer 1700. The removal of the etching mask layer 1600 or the etching pattern layer 1700 can be achieved by typical processes. For example, the process can be reactive ion etching (RIE), inductively coupled plasma reactive ion etching (ICP-RIE), etc. However, the present disclosure is not limited thereto.

[0110] Thereafter, a semiconductor rod ROD is formed by forming an insulating film 380 that partially surrounds the outer surface of the semiconductor crystal 3000'.

[0111] Referring Figure 12 and Figure 13 , the insulating film 380 can be formed by forming an insulating coating film 3800 around the outer surface of the semiconductor crystal 3000', and then partially removing the insulating coating film 3800 so that the bottom surface of the first electrode layer 371 (corresponding to Figures 12 to 13 the upper surface in

[0112] is exposed. Since the insulating coating film 3800 is formed on the outer surface of the semiconductor crystal 3000' having the first electrode layer 371, the insulating film 380 of the light-emitting element 300 can also be formed on the outer side surface of the first electrode layer 371.

[0113] An insulating coating film 3800 may also be formed on the side and bottom surfaces of the semiconductor crystal 3000' and on the bonding layer 5100 exposed in the region between the semiconductor crystals 3000'. The insulating coating film 3800 may be partially removed such that the bottom surface of the first electrode layer 371 is exposed. The partial removal of the insulating coating film 3800 may be achieved by etchback or dry etching, which is an anisotropic etching. In the drawings, the bottom surface of the insulating coating film 3800 is removed to expose the first electrode layer 371, and the bottom surface of the insulating film 380 is shown to be flat. However, the present disclosure is not limited thereto. In some embodiments, the insulating film 380 may be formed to have a partially curved outer surface in the region where it surrounds the first electrode layer 371. During the partial removal of the insulating coating film 3800, the side surface as well as the bottom surface of the insulating coating film 3800 may be partially removed such that an insulating film 380 surrounding a plurality of layers with a partially etched end face may be formed. In particular, as the bottom surface of the insulating coating film 3800 is removed, in the light-emitting element 300, the outer surface of the insulating film 380 adjacent to the first electrode layer 371 may be partially removed. The description thereof may refer to other embodiments.

[0114] Finally, a second separation step of separating the semiconductor rod ROD as shown in Figure 14 is performed to obtain the light-emitting element 300. The second separation step may be achieved by physically separating the semiconductor rod ROD from the bonding layer 5100 or by chemically removing the bonding layer 5100. The drawings show an example in which the semiconductor rod ROD is physically removed from the bonding layer 5100 such that the bonding layer 5100 remains on the support layer 5200. However, it is not limited thereto, and the semiconductor rod ROD may be separated from the support layer 5200 by removing the bonding layer 5100. The detailed description thereof will be omitted.

[0115] Through the above process, a light-emitting element 300 according to one embodiment may be manufactured. The method of manufacturing the light-emitting element 300 may include: a first separation step of separating the semiconductor structure 3000 from the underlying substrate 2000; and a second separation step of separating the semiconductor rod ROD from the bonding layer 5100. The plurality of layers of the light-emitting element 300 may be sequentially formed starting from the first semiconductor layer 3100 along its stacking direction, and the first electrode layer 371 may be formed after the first separation step. In order to form the light-emitting element 300 extending in one direction, the semiconductor structure 3000 may be etched from the bottom surface of the first electrode material layer 3710 in the one direction to form the semiconductor crystal 3000'. Further, since the process of etching the semiconductor structure 3000 in the one direction is performed after the first electrode material layer 3710 is formed, the insulating film 380 of the light-emitting element 300 according to one embodiment may also be formed on the outer side surface of the first electrode layer 371.

[0116] In the following, a light-emitting element 300 according to other embodiments will be described.

[0117] Figure 15 is a cross-sectional view of a light-emitting element according to another embodiment. Figure 16 is Figure 15 a partial enlarged view of part Q of

[0118] Referring to Figure 15 and Figure 16 and according to an embodiment, at at least one end of the light-emitting element 300_1, an insulating film 380_1 surrounding the outer surface of the light-emitting element 300_1 may have a shape including a partially curved end face. Figure 15 The light-emitting element 300_1 of Figure 1 differs from the light-emitting element 300 of Figure 1 in that the end face of the insulating film 380_1 has a curved shape. Except for this difference, the layout and structure of the first electrode layer 371_1, the first semiconductor layer 310_1, the active layer 360_1, etc. are the same as those shown in

[0119] According to an embodiment, the insulating film 380_1 may include a first surface 380S_1 extending in one direction to form the outer surface of the light-emitting element 300_1, and a second surface 380C1_1 and a third surface 380C2_1 that connect the end faces of the light-emitting element 300_1 (i.e., the end faces of the first electrode layer 371_1 and the second electrode layer 372_1) to the first surface 380S_1, respectively. The second surface 380C1_1 may have a partially curved shape. That is, the thickness of the first region surrounding the side surface of the active layer 360_1 of the insulating film 380_1 may be greater than the thickness of the second region surrounding the side surface of the first electrode layer 371_1.

[0120] The light-emitting element 300_1 may have a first end face that is the bottom surface of the first electrode layer 371_1 and a second end face that is the top surface of the second electrode layer 372_1. The first end face may be the surface exposed as the insulating coating film 3800 is partially removed during the manufacturing process of the light-emitting element 300_1, and the second end face may be the surface that comes into contact with the adhesive layer 5100 in the first separation step. The insulating film 380_1 may include a first surface 380S_1 that extends in one direction to form the outer surface of the light-emitting element 300_1. Depending on the shape of the light-emitting element 300_1, the first surface 380S_1 may have a curved or flat shape. Here, as shown in the drawings, the first surface 380S_1 may be formed as a flat surface in a cross-sectional view. The insulating film 380_1 may include a second surface 380C1_1 that connects the first surface 380S_1 and the first end face of the light-emitting element 300_1, and a third surface 380C2_1 that connects the first surface 380S_1 and the second end face of the light-emitting element 300_1. The second surface 380C1_1 may be the surface positioned adjacent to the first electrode layer 371_1 of the light-emitting element 300_1, and the third surface 380C2_1 may be the surface positioned adjacent to the second electrode layer 372_1. According to one embodiment, at least a portion of the second surface 380C1_1 of the insulating film 380_1 may be curved, and the third surface 380C2_1 of the insulating film 380_1 may be formed as a flat surface. The third surface 380C2_1 may be at the same level as the top surface of the second electrode layer 372_1.

[0121] As described above, since the method of manufacturing the light-emitting element 300 includes the step of forming the semiconductor crystal 3000' by etching the semiconductor structure 3000 in the direction from the first electrode layer 371 toward the second electrode layer 372, the region where the insulating coating film 3800 is removed to form the insulating film 380 may be the region where the first electrode layer 371 is provided. The insulating film 380 of the light-emitting element 300 may be formed by a process of partially removing the insulating coating film 3800 to expose the end face of the first electrode layer 371. As Figure 13 depicted, the process of partially removing the insulating coating film 3800 may be achieved by performing etching in a direction perpendicular to the support layer 5200 or the adhesive layer 5100. Therefore, at least one side end face of the insulating film 380 of the light-emitting element 300 may be partially removed by the process of partially removing the insulating coating film 3800.

[0122] Correspondingly, in Figure 15In the process of manufacturing the light-emitting element 300_1, the insulating coating film 3800 is partially removed to expose the first end face where the first electrode layer 371_1 is located. As the material for forming the insulating film 380_1 is partially removed, the thus-formed insulating film 380_1 can be given a partially curved second surface 380C1_1. At the same time, the insulating coating film 3800 is not removed at the second end face where the second electrode layer 372_1 is located, and the insulating coating film 3800 is separated from the adhesive layer 5100. Therefore, the insulating film 380_1 can be given a third surface 380C2_1 that is a flat surface. This structure can be obtained by etching the semiconductor structure 3000 in one direction from the bottom surface of the first electrode material layer 3710 downward in the process of manufacturing the light-emitting element 300_1, and performing a process of partially removing the insulating coating film 3800 to expose the bottom surface of the first electrode layer 371_1.

[0123] In addition, according to one embodiment, the distance between the curved second surface 380C1_1 of the insulating film 380_1 and the active layer 360_1 can be greater than the distance between the flat third surface 380C2_1 of the insulating film 380_1 and the active layer 360_1. The second surface 380C1_1 can be positioned adjacent to the bottom surface of the first semiconductor layer 310_1 where the first electrode layer 371_1 is located. The third surface 380C2_1 can be positioned adjacent to the top surface of the second semiconductor layer 320_1 where the second electrode layer 372_1 is located. In the light-emitting element 300_1, since the distance dd1 between the active layer 360_1 and the first electrode layer 371_1 (i.e., the length dd1 of the first semiconductor layer 310_1) is greater than the distance dd2 between the active layer 360_1 and the second electrode layer 372_1 (i.e., the length dd2 of the second semiconductor layer 320_1), therefore, the distance between the active layer 360_1 and the second surface 380C1_1 can be greater than the distance between the active layer 360_1 and the third surface 380C2_1. Therefore, among the surfaces of the insulating film 380_1 of the light-emitting element 300_1, the second surface 380C1_1 having a partially curved outer surface can be positioned farther from the active layer 360_1 than the flat third surface 380C2_1. However, the present disclosure is not limited thereto. In some cases, the second surface 380C1_1 can be positioned closer to the active layer 360_1 than the third surface 380C2_1.

[0124] Figure 17 is a cross-sectional view of a light-emitting element according to still another embodiment.

[0125] Referring to Figure 17, according to an embodiment, the diameter of the light-emitting element 300_2 can increase as it travels from one end towards the other end. That is, in the light-emitting element 300_2, the second semiconductor layer 320_2 can have a diameter W2 that is larger than the diameter W1 of the first semiconductor layer 310_2. Figure 17 The light-emitting element 300_2 of Figure 1 differs from the light-emitting element 300 of Figure 1 in that its diameter varies according to position. Except for this difference, the layout and structure of the first electrode layer 371_2, the first semiconductor layer 310_2, the active layer 360_2, the insulating film 380_2, etc. are the same as those described in

[0126] According to one embodiment, the diameter of the light-emitting element 300_2 can increase as it travels from the first end where the first electrode layer 371_2 is located towards the second end where the second electrode layer 372_2 is located. During the manufacturing process of the light-emitting element 300_2, the process of etching the semiconductor structure 3000 in one direction can be performed in the downward direction from the top surface of the first electrode material layer 3710. Therefore, the upper part of the semiconductor structure 3000 where the first electrode material layer 3710 is located can be etched more than the lower part of the semiconductor structure 3000. That is, the semiconductor crystal 3000' formed by etching the semiconductor structure 3000 is formed such that the first electrode layer 371_2 is etched more than the second electrode layer 372_2, and the diameter of the semiconductor crystal 3000' can decrease as it travels from the second electrode layer 372_2 to the first electrode layer 371_2.

[0127] As shown in the drawings, the diameter of the light-emitting element 300_2 increases as it travels from the first electrode layer 371_2 to the second electrode layer 372_2, and the light-emitting element 300_2 can have a shape in which the outer surface is inclined with respect to a direction in which the light-emitting element 300_2 extends. In some embodiments, the diameter W1 measured at the bottom surface of the first semiconductor layer 310_2 where the first electrode layer 371_2 is located can be smaller than the diameter W2 measured at the top surface of the second semiconductor layer 320_2 where the second electrode layer 372_2 is located.

[0128] Meanwhile, different from Figure 1 the light-emitting element 300, the light-emitting element 300' according to an embodiment (see Figure 18 ) can include a larger number of semiconductor layers, and the active layer 360' (see Figure 18 ) can include different elements and emit light of a color different from blue.

[0129] Figure 18 is a schematic diagram showing a light-emitting element according to another embodiment.Figure 19 is a cross-sectional view of a light-emitting element taken along line III-III' Figure 18 as shown in the figure below.

[0130] Referring to Figure 18 and Figure 19 , the light-emitting element 300' according to the embodiment may further include a third semiconductor layer 330' disposed between the first semiconductor layer 310' and the active layer 360', and a fourth semiconductor layer 340' and a fifth semiconductor layer 350' disposed between the active layer 360' and the second semiconductor layer 320'. Figure 18 and Figure 19 The light-emitting element 300' shown in Figure 1 and Figure 2 differs from the embodiment shown in Figure 1 in that: a plurality of semiconductor layers 330', 340' and 350' are further provided, and the active layer 360' includes different elements. Except for this difference, the layout and structure of the first electrode layer 371', the second electrode layer 372' and the insulating film 380' may be substantially the same as those described in

[0131] As described above, Figure 1 and Figure 2 the active layer 360 of the light-emitting element 300 shown in Figure 18 and Figure 19 may include nitrogen (N) and may emit blue or green light. At the same time,

[0132] Specifically, if the first semiconductor layer 310' is an n-type semiconductor layer and the light-emitting element 300' emits red light, the first semiconductor layer 310' may include indium having the chemical formula In x Al y Ga 1-x-yA semiconductor material of P(0≤x≤1, 0≤y≤1, 0≤x + y≤1). For example, the first semiconductor layer 310' can be any one or more of InAlGaP, GaP, AlGaP, InGaP, AlP, and InP doped with n-type. The first semiconductor layer 310' can be doped with a first conductive dopant. For example, the first conductive dopant can be Si, Ge, Sn, etc. In an embodiment, the first semiconductor layer 310' can be n-AlGaInP doped with n-type Si. The length of the first semiconductor layer 310' can range from 1.5 μm to 5 μm, but is not limited thereto.

[0133] If the second semiconductor layer 320' is a p-type semiconductor layer and the light-emitting element 300' emits red light, the second semiconductor layer 320' can include a semiconductor material of In x Al y Ga 1-x-y P(0≤x≤1, 0≤y≤1, 0≤x + y≤1). For example, the second semiconductor layer 320' can be any one or more of InAlGaP, GaP, AlGaNP, InGaP, AlP, and InP doped with p-type. The second semiconductor layer 320' can be doped with a second conductive dopant. For example, the second conductive dopant can be Mg, Zn, Ca, Se, Ba, etc. In an embodiment, the second semiconductor layer 320' can be p-GaP doped with p-type Mg. The length of the second semiconductor layer 320' can range from 0.08 μm to 0.25 μm, but is not limited thereto.

[0134] The active layer 360' can be disposed between the first semiconductor layer 310' and the second semiconductor layer 320'. Similar to Figure 1 the active layer 360, Figure 18 and Figure 19 the active layer 360' can also include a material having a single quantum well structure or a multi-quantum well structure and emitting light in a specific wavelength band. For example, when the active layer 360' emits light in the red wavelength band, the active layer 360' can include materials such as AlGaP, AlInGaP, etc. In particular, when the active layer 360' has a structure in which quantum layers and well layers are alternately stacked into a multi-quantum well structure, the quantum layers can include materials such as AlGaP or AlInGaP, and the well layers can include materials such as GaP or AlInP. In an embodiment, the active layer 360' can include AlGaInP as the quantum layer and AlInP as the well layer to emit red light having a central wavelength band of 620 nm to 750 nm.

[0135] Figure 18 and Figure 19The light-emitting element 300' may include a cladding layer disposed adjacent to the active layer 360'. As shown in the drawings, the third semiconductor layer 330' and the fourth semiconductor layer 340' respectively disposed below and above the active layer 360' between the first semiconductor layer 310' and the second semiconductor layer 320' may be cladding layers.

[0136] The third semiconductor layer 330' may be disposed between the first semiconductor layer 310' and the active layer 360'. The third semiconductor layer 330' may be an n-type semiconductor in the same manner as the first semiconductor layer 310'. For example, the third semiconductor layer 330' may include a semiconductor material represented by the chemical formula In x Al y Ga 1-x-y P (0≤x≤1, 0≤y≤1, 0≤x + y≤1). In an embodiment, the first semiconductor layer 310' may be n-AlGaInP, and the third semiconductor layer 330' may be n-AlInP. However, it is not limited thereto.

[0137] The fourth semiconductor layer 340' may be disposed between the active layer 360' and the second semiconductor layer 320'. The fourth semiconductor layer 340' may be an n-type semiconductor in the same manner as the second semiconductor layer 320'. For example, the fourth semiconductor layer 340' may include a semiconductor material represented by the chemical formula In x Al y Ga 1-x-y P (0≤x≤1, 0≤y≤1, 0≤x + y≤1). In an embodiment, the second semiconductor layer 320' may be p-GaP, and the fourth semiconductor layer 340' may be p-AlInP.

[0138] The fifth semiconductor layer 350' may be disposed between the fourth semiconductor layer 340' and the second semiconductor layer 320'. The fifth semiconductor layer 350' may be a p-type doped semiconductor in the same manner as the second semiconductor layer 320' and the fourth semiconductor layer 340'. In some embodiments, the fifth semiconductor layer 350' may function to reduce the lattice constant difference between the fourth semiconductor layer 340' and the second semiconductor layer 320'. That is, the fifth semiconductor layer 350' may be a tensile strain barrier reduction (TSBR) layer. For example, the fifth semiconductor layer 350' may include p-GaInP, p-AlInP, p-AlGaInP, etc., but is not limited thereto.

[0139] The first electrode layer 371' and the second electrode layer 372' may be in contact with Figure 1In the light-emitting element 300, they are identically provided on the first semiconductor layer 310' and the second semiconductor layer 320' respectively. The first electrode layer 371' may be provided on the bottom surface of the first semiconductor layer 310', and the second electrode layer 372' may be provided on the top surface of the second semiconductor layer 320'. Figure 18 and Figure 19 The light-emitting element 300' can be manufactured in substantially the same manner as Figure 1 the light-emitting element 300. That is, in order to manufacture Figure 18 and Figure 19 the light-emitting element 300', after forming the semiconductor structure 3000 including a plurality of semiconductor layers and the active layer 360', the semiconductor structure 3000 can be separated from the bottom substrate 2000, and the first electrode layer 371' can be formed on the exposed separation surface of the first semiconductor layer 310'. In the light-emitting element 300' having a shape extending in one direction, the semiconductor structure 3000 can be etched in the direction from the first electrode layer 371' toward the second electrode layer 372'. Its detailed description will be omitted because it is the same as the above.

[0140] Meanwhile, according to one embodiment, the display device 10 may include the above-described light-emitting element 300 to display light in a specific wavelength band. In some embodiments, the display device 10 may include Figure 1 the light-emitting element 300 to display blue light or green light, or may include Figure 18 the light-emitting element 300' to display red light.

[0141] Figure 20 is a schematic plan view of a display device according to one embodiment.

[0142] Referring to Figure 20 , the display device 10 displays a moving image or a still image. The display device 10 may refer to any electronic device providing a display screen. Examples of the display device 10 may include a television, a laptop computer, a monitor, a billboard, an Internet of Things device, a mobile phone, a smart phone, a tablet personal computer (PC), an electronic watch, a smart watch, a watch phone, a head-mounted display, a mobile communication terminal, an electronic notebook, an e-book, a portable multimedia player (PMP), a navigation device, a game console, a digital camera, a portable video camera, etc. that provide a display screen.

[0143] The display device 10 includes a display panel providing a display screen. Examples of the display panel may include an LED display panel, an organic light-emitting display panel, a quantum dot light-emitting display panel, a plasma display panel, and a field emission display panel. In the following description, the case where an LED display panel is used as the display panel will be illustrated, but the present disclosure is not limited thereto, and other display panels can be applied within the same scope of the technical spirit.

[0144] Various modifications can be made to the shape of the display device 10. For example, the display device 10 can have a shape such as a rectangular shape extended in the horizontal direction, a rectangular shape extended in the vertical direction, a square shape, a quadrilateral shape with rounded corners (vertices), other polygonal shapes, and a circular shape. The shape of the display area DA of the display device 10 can also be similar to the overall shape of the display device 10. In Figure 20 FIG., a display device 10 and a display area DA having a rectangular shape extended in the horizontal direction are shown.

[0145] The display device 10 can include a display area DA and a non-display area NDA. The display area DA is an area where a screen can be displayed, and the non-display area NDA is an area where no screen is displayed. The display area DA can also be referred to as an effective area, and the non-display area NDA can also be referred to as a non-effective area.

[0146] The display area DA can substantially occupy the center of the display device 10. The display area DA can include a plurality of pixels PX. The plurality of pixels PX can be arranged in a matrix. In a plan view, the shape of each pixel PX can be rectangular or square. However, the present disclosure is not limited thereto, and it can be a rhombus shape in which each side is inclined with respect to the first direction DR1. Each of the pixels PX can include one or more light-emitting elements 300 that emit light in a specific wavelength band to display a specific color.

[0147] Figure 21 is a schematic plan view of a pixel of a display device according to one embodiment.

[0148] Referring to Figure 21 , each of the pixels PX can include a first sub-pixel PX1, a second sub-pixel PX2, and a third sub-pixel PX3 (collectively referred to as PXn). The first sub-pixel PX1 can emit light of a first color, the second sub-pixel PX2 can emit light of a second color, and the third sub-pixel PX3 can emit light of a third color. The first color can be blue, the second color can be green, and the third color can be red, but they are not limited thereto. All the sub-pixels PXn can emit light of the same color. In addition, although Figure 21 FIG. shows that the pixel PX includes three sub-pixels PXn, the present disclosure is not limited thereto, and the pixel PX can include a larger number of sub-pixels PXn.

[0149] Meanwhile, in the present disclosure, although "first", "second", etc. are used to refer to individual components, they are used only to simply distinguish the components and do not necessarily limit the components. That is, the components defined as "first", "second", etc. do not have to be limited to a specific structure or position, and in some cases, other reference numerals may be assigned. Therefore, the reference numerals assigned to the respective components can be explained by the drawings and the following description, and the first component mentioned below can be the second component within the technical idea of the present disclosure.

[0150] Each sub-pixel PXn of the display device 10 may include a region defined as an emission region EMA. The first sub-pixel PX1 may include a first emission region EMA1, the second sub-pixel PX2 may include a second emission region EMA2, and the third sub-pixel PX3 may include a third emission region EMA3. The emission region EMA may be defined as a region in which the light-emitting elements 300 included in the display device 10 are arranged to emit light in a specific wavelength band. The light-emitting element 300 includes an active layer 360, and the active layer 360 may emit light in a specific wavelength band without directionality. That is, the light emitted from the active layer 360 of the light-emitting element 300 may be irradiated in the lateral direction of the light-emitting element 300 and in the directions at both ends of the light-emitting element 300. The emission region EMA of each sub-pixel PXn may include a region adjacent to the light-emitting element 300 irradiated by the light emitted from the light-emitting element 300, including the region where the light-emitting element 300 is provided. In addition, without being limited thereto, the emission region EMA may further include a region where the light emitted from the light-emitting element 300 is reflected or refracted by another member and then emitted. A plurality of light-emitting elements 300 may be provided in each sub-pixel PXn, and the emission region EMA may be formed to include the region where the light-emitting element 300 is provided and the region adjacent thereto.

[0151] Although not shown in the drawings, each sub-pixel PXn of the display device 10 may include a non-emission region defined as a region other than the emission region EMA. The non-emission region may be defined as a region where no light-emitting element 300 is provided and a region that does not emit light because the light emitted from the light-emitting element 300 does not reach it. Each sub-pixel PXn of the display device 10 may include a plurality of electrodes 210 and 220, a light-emitting element 300, a plurality of banks 410, 420, and 430 (see Figure 21 and Figure 22 ) and at least one insulating layer 510, 520, or 550 (see Figure 22 ).

[0152] The electrodes 210 and 220 can be electrically connected to the light-emitting element 300 and can receive a preset voltage applied thereto to cause the light-emitting element 300 to emit light in a specific wavelength band. In addition, at least a part of each of the electrodes 210 and 220 can be used to form an electric field within the sub-pixel PXn to align the light-emitting element 300.

[0153] The plurality of electrodes 210 and 220 can include a first electrode 210 and a second electrode 220. In an embodiment, the first electrode 210 can be a pixel electrode separated for each sub-pixel PXn, and the second electrode 220 can be a common electrode connected along the respective sub-pixels PXn to be shared by the sub-pixels PXn. One of the first electrode 210 and the second electrode 220 can be an anode electrode of the light-emitting element 300, and the other can be a cathode electrode of the light-emitting element 300. However, the present disclosure is not limited thereto, and the opposite case is also possible.

[0154] The first electrode 210 and the second electrode 220 can include respective electrode bars 210S and 220S arranged to extend in a first direction DR1 and at least one corresponding electrode branch 210B and 220B extending from the respective electrode bars 210S and 220S in a second direction DR2 intersecting the first direction DR1.

[0155] The first electrode 210 can include a first electrode bar 210S extending in the first direction DR1 and at least one first electrode branch 210B branching from the first electrode bar 210S and extending in the second direction DR2.

[0156] The first electrode bar 210S of any one pixel PX can be arranged such that both ends of the respective first electrode bars 210S terminate at a gap between the respective sub-pixels PXn, and each first electrode bar 210S is arranged on substantially the same straight line as the first electrode bars 210S of the sub-pixels PXn adjacent thereto in the same row (e.g., in the first direction DR1). Since the first electrode bars 210S provided in the respective sub-pixels PXn are arranged such that both ends thereof are spaced apart from each other, different electrical signals can be applied to the first electrode branches 210B, and thus the first electrode branches 210B can be driven individually.

[0157] The first electrode branch 210B can branch from at least a part of the first electrode bar 210S and extend in the second direction DR2, and can terminate while being spaced apart from the second electrode bar 220S arranged to face the first electrode bar 210S.

[0158] The second electrode 220 may include a second electrode bar 220S that extends in a first direction DR1 and is arranged to face the first electrode bar 210S while being spaced apart from the first electrode bar 210S in a second direction DR2, and a second electrode branch 220B that branches from the second electrode bar 220S and extends in the second direction DR2. The second electrode bar 220S may be connected at the other end to the second electrode bar 220S of another sub-pixel PXn adjacent to it in the first direction DR1. That is, unlike the first electrode bar 210S, the second electrode bar 220S may extend across each sub-pixel PXn in the first direction DR1. The second electrode bar 220S that extends across each sub-pixel PXn may be connected to the outside of the display area DA where each pixel PX or sub-pixel PXn is arranged, or to an extension portion that extends from the non-display area NDA in one direction.

[0159] The second electrode branch 220B may be arranged to face the first electrode branch 210B with a gap therebetween, and may terminate while being spaced apart from the first electrode bar 210S. The second electrode branch 220B may be connected to the second electrode bar 220S, and one end of the second electrode branch 220B in the extending direction may be arranged within the sub-pixel PXn while being spaced apart from the first electrode bar 210S.

[0160] In the drawings, two first electrode branches 210B are shown arranged in each sub-pixel PXn, and one second electrode branch 220B is arranged between the two first electrode branches 210B. However, the layout of the first electrode branch 210B and the second electrode branch 220B may not be limited to this. In addition, the first electrode 210 and the second electrode 220 do not have to have a shape that extends in one direction, and they may have various layouts. For example, the first electrode 210 and the second electrode 220 may have a partially curved or bent shape, and one electrode may be arranged to surround the other electrode. The layout and shape of the first electrode 210 and the second electrode 220 may not be particularly limited as long as at least some portions of the first electrode 210 and the second electrode 220 face each other and there is a gap therebetween so as to create a space where the light-emitting element 300 can be arranged.

[0161] In addition, the first electrode 210 and the second electrode 220 may be respectively connected to the circuit element layer PAL of the display device 10 (see Figure 22) Electrical connection. In the drawings, a first electrode contact hole CNTD is shown formed at each first electrode bar 210S of each sub-pixel PXn, while only one second electrode contact hole CNTS is formed at a single second electrode bar 220S extending across the respective sub-pixels PXn. However, the present disclosure is not limited thereto, and if necessary, a second electrode contact hole CNTS may also be formed for each sub-pixel PXn.

[0162] The plurality of banks 410, 420, and 430 may include an external bank 430 disposed at the boundary between the sub-pixels PXn and internal banks 410 and 420 disposed adjacent to the center of each sub-pixel PXn below the electrodes 210 and 220. Although the plurality of internal banks 410 and 420 are not shown in the drawings, a first internal bank 410 and a second internal bank 420 may be respectively disposed below the first electrode branch 210B and the second electrode branch 220B. A description thereof will be given later with reference to other drawings.

[0163] The external bank 430 may be disposed at the boundary between the sub-pixels PXn. The first electrode bars 210S may terminate such that their respective ends are spaced apart from each other and the external bank 430 is located between the ends. Each external bank 430 may extend in the second direction DR2 to be disposed at the boundary between adjacent sub-pixels PXn arranged in the first direction DR1. However, the present disclosure is not limited thereto, and the external bank 430 may extend in the first direction DR1 to be disposed at the boundary between adjacent sub-pixels PXn arranged in the second direction DR2. The external bank 430 may include the same material as the internal banks 410 and 420, and these external bank 430 and internal banks 410 and 420 may be formed simultaneously in one process.

[0164] The plurality of light-emitting elements 300 may be disposed between the first electrode 210 and the second electrode 220. As shown in the drawings, the light-emitting elements 300 may be disposed between the first electrode branch 210B and the second electrode branch 220B. At least some of the plurality of light-emitting elements 300 may be electrically connected to the first electrode 210 at one end thereof and to the second electrode 220 at the other end thereof. Each light-emitting element 300 may be disposed such that its two ends are respectively located on the first electrode branch 210B and the second electrode branch 220B, but is not limited thereto. In some cases, the light-emitting element 300 may be disposed between the first electrode 210 and the second electrode 220 so that the two ends of the light-emitting element 300 do not overlap with the first electrode 210 and the second electrode 220.

[0165] A plurality of light-emitting elements 300 may be arranged substantially parallel to each other while being spaced apart from each other between the electrodes 210 and 220. The spacing between the light-emitting elements 300 is not particularly limited. In some cases, a plurality of light-emitting elements 300 may be arranged adjacent to each other to form a group, and other plurality of light-emitting elements 300 may be arranged to form another group while being spaced apart from each other by a certain distance. That is, the light-emitting elements 300 may be arranged at different densities, but they may still be aligned in one direction. In addition, in an embodiment, the light-emitting element 300 may have a shape extending in one direction, and the extending direction of the electrodes (e.g., the first electrode branch 210B and the second electrode branch 220B) may be substantially perpendicular to the extending direction of the light-emitting element 300. However, the present disclosure is not limited thereto, and the light-emitting element 300 may be disposed diagonally with respect to the extending direction of the first electrode branch 210B and the second electrode branch 220B instead of being perpendicular thereto.

[0166] Meanwhile, the light-emitting element 300 according to an embodiment may have an active layer 360 including different materials, and thus may emit light in different wavelength bands to the outside. The display device 10 according to an embodiment may include the light-emitting elements 300 that emit light in different wavelength bands. The display device 10 may include a first light-emitting element 301 disposed in the first sub-pixel PX1, a second light-emitting element 302 disposed in the second sub-pixel PX2, and a third light-emitting element 303 disposed in the third sub-pixel PX3.

[0167] The first light-emitting element 301 and the second light-emitting element 302 may have the same structure as the Figure 1 light-emitting element 300. The first light-emitting element 301 may include an active layer 360 that emits first light L1 having a first wavelength as a central wavelength band, and the second light-emitting element 302 may include an active layer 360 that emits second light L2 having a second wavelength as a central wavelength band. Accordingly, the first light L1 may be irradiated from the first sub-pixel PX1, and the second light L2 may be irradiated from the second sub-pixel PX2. The third light-emitting element 303 may be the same as Figure 17The light-emitting element 300' also includes an active layer 360' that emits third light L3 having a third wavelength as a central wavelength band, in the same way. Different from the first light-emitting element 301 and the second light-emitting element 302, the third light-emitting element 303 may further include a third semiconductor layer 330', a fourth semiconductor layer 340', and a fifth semiconductor layer 350'. The third light L3 may be irradiated from the third sub-pixel PX3. In some embodiments, the display device 10 may include light-emitting elements including active layers 360 that emit lights of different colors, such as the first light-emitting element 301, the second light-emitting element 302, and the third light-emitting element 303. Each of the first light-emitting element 301, the second light-emitting element 302, and the third light-emitting element 303 may include active layers 360 and 360' that respectively emit first light L1, second light L2, and third light L3.

[0168] In some embodiments, the first light L1 may be blue light having a central wavelength band of 450 nm to 495 nm, the second light L2 may be green light having a central wavelength band of 495 nm to 570 nm, and the third light L3 may be red light having a central wavelength band of 620 nm to 750 nm. However, the present disclosure is not limited thereto. The first light L1, the second light L2, and the third light L3 may have different colors, or may have the same color, but their central wavelength bands may be different from the ranges specified above.

[0169] In addition, although not shown in the drawings, the display device 10 may include a first insulating layer 510 that covers at least a part of the first electrode 210 and at least a part of the second electrode 220 (see Figure 22 ).

[0170] The first insulating layer 510 may be provided in each sub-pixel PXn of the display device 10. The first insulating layer 510 may be provided to substantially completely cover each sub-pixel PXn, and may extend to other adjacent sub-pixels PXn. The first insulating layer 510 may be provided to cover at least a part of the first electrode 210 and at least a part of the second electrode 220. Although not shown in Figure 22 , the first insulating layer 510 may be provided to expose some regions of the first electrode 210 and the second electrode 220, specifically, some regions of the first electrode branch 210B and the second electrode branch 220B.

[0171] In addition to the first insulating layer 510, the display device 10 may further include a circuit element layer PAL, a second insulating layer 520 (see Figure 22 ) and a passivation layer 550 (also referred to as an insulating layer 550) (see Figure 22), wherein the circuit element layer PAL is disposed below the electrodes 210 and 220, and the second insulating layer 520 is disposed to cover at least some portions of the electrodes 210 and 220 and the light emitting element 300. Hereinafter, with reference to Figure 22 The structure of the display device 10 will be described in detail.

[0172] Figure 22 is a cross-sectional view taken along the Figure 21 lines Xa-Xa', Xb-Xb' and Xc-Xc'.

[0173] Figure 22 Only the cross-section of the second sub-pixel PX2 is shown, but they can be applied to other pixels PX or sub-pixels PXn. Figure 22 shows a cross-section across one end and the other end of a certain light emitting element 300.

[0174] With reference to Figure 21 and Figure 22 , the display device 10 may include a circuit element layer PAL and an emission layer EML. The circuit element layer PAL may include a substrate 110, a buffer layer 115, a light blocking layer BML, a first transistor 120, a second transistor 140, etc. The emission layer EML may include a plurality of electrodes 210 and 220 disposed on the first transistor 120 and the second transistor 140, a light emitting element 300, a plurality of insulating layers 510, 520 and 550, etc.

[0175] The substrate 110 may be an insulating substrate. The substrate 110 may be made of an insulating material such as glass, quartz, or polymer resin. In addition, the substrate 110 may be a rigid substrate, but may also be a flexible substrate capable of being bent, folded, or curled.

[0176] The light blocking layer BML may be disposed on the substrate 110. The light blocking layer BML may include a first light blocking layer BML1 and a second light blocking layer BML2. The first light blocking layer BML1 may be electrically connected to a first drain electrode 123 of the first transistor 120 to be described later. The second light blocking layer BML2 may be electrically connected to a second drain electrode 143 of the second transistor 140.

[0177] The first light blocking layer BML1 and the second light blocking layer BML2 are arranged to overlap with a first active material layer 126 of the first transistor 120 and a second active material layer 146 of the second transistor 140, respectively. The first light blocking layer BML1 and the second light blocking layer BML2 may include a material that blocks light, and thus may prevent light from reaching the first active material layer 126 and the second active material layer 146. For example, the first light blocking layer BML1 and the second light blocking layer BML2 may be formed of an opaque metal material that blocks light transmission. However, the present disclosure is not limited thereto, and in some cases, the light blocking layer BML may be omitted.

[0178] The buffer layer 115 is disposed on the light-blocking layer BML and the substrate 110. The buffer layer 115 may be disposed to cover the entire surface of the substrate 110, including the light-blocking layer BML. The buffer layer 115 can prevent the diffusion of impurity ions, prevent the penetration of moisture or external air, and perform a surface planarization function. In addition, the buffer layer 115 can be used to insulate the light-blocking layer BML and the first active material layer 126 and the second active material layer 146 from each other.

[0179] The semiconductor layer is disposed on the buffer layer 115. The semiconductor layer may include a first active material layer 126 of the first transistor 120, a second active material layer 146 of the second transistor 140, and an auxiliary layer 163. The semiconductor layer may include polysilicon, single-crystalline silicon, an oxide semiconductor, and the like.

[0180] The first active material layer 126 may include a first doped region 126a, a second doped region 126b, and a first channel region 126c. The first channel region 126c may be disposed between the first doped region 126a and the second doped region 126b. The second active material layer 146 may include a third doped region 146a, a fourth doped region 146b, and a second channel region 146c. The second channel region 146c may be disposed between the third doped region 146a and the fourth doped region 146b. The first active material layer 126 and the second active material layer 146 may include polysilicon. The polysilicon may be formed by crystallizing amorphous silicon. Examples of the crystallization method may include rapid thermal annealing (RTA), solid-phase crystallization (SPC), excimer laser annealing (ELA), metal-induced lateral crystallization (MILC), and sequential lateral solidification (SLS), but are not limited thereto. As another example, the first active material layer 126 and the second active material layer 146 may include single-crystalline silicon, low-temperature polysilicon, amorphous silicon, and the like. The first doped region 126a, the second doped region 126b, the third doped region 146a, and the fourth doped region 146b may be some regions of the first active material layer 126 and the second active material layer 146 doped with impurities. However, the present disclosure is not limited thereto.

[0181] The first gate insulating film 150 is disposed on the semiconductor layer. The first gate insulating film 150 may be disposed to cover the entire surface of the buffer layer 115, including the semiconductor layer. The first gate insulating film 150 can be used as a gate insulating film for the first transistor 120 and the second transistor 140.

[0182] The first conductive layer is disposed on the first gate insulating film 150. The first conductive layer may include a first gate electrode 121 disposed on the first active material layer 126 of the first transistor 120, a second gate electrode 141 disposed on the second active material layer 146 of the second transistor 140, and a power line 161 disposed on the auxiliary layer 163 on the first gate insulating film 150. The first gate electrode 121 may overlap with the first channel region 126c of the first active material layer 126, and the second gate electrode 141 may overlap with the second channel region 146c of the second active material layer 146.

[0183] The interlayer insulating film 170 is disposed on the first conductive layer. The interlayer insulating film 170 may be used as an insulating film between layers. In addition, the interlayer insulating film 170 may include an organic insulating material and may also perform a surface planarization function.

[0184] The second conductive layer is disposed on the interlayer insulating film 170. The second conductive layer includes a first drain electrode 123 and a first source electrode 124 of the first transistor 120, a second drain electrode 143 and a second source electrode 144 of the second transistor 140, and a power electrode 162 disposed on the power line 161.

[0185] The first drain electrode 123 and the first source electrode 124 may be in contact with the first doped region 126a and the second doped region 126b of the first active material layer 126 through contact holes formed by penetrating the interlayer insulating film 170 and the first gate insulating film 150, respectively. The second drain electrode 143 and the second source electrode 144 may be in contact with the third doped region 146a and the fourth doped region 146b of the second active material layer 146 through contact holes formed by penetrating the interlayer insulating film 170 and the first gate insulating film 150, respectively. In addition, the first drain electrode 123 and the second drain electrode 143 may be electrically connected to the first light blocking layer BML1 and the second light blocking layer BML2 through other contact holes, respectively.

[0186] The via layer 200 is disposed on the second conductive layer. The via layer 200 includes an organic insulating material and may perform a surface planarization function.

[0187] A plurality of dams 410, 420, and 430, a plurality of electrodes 210 and 220, and a light emitting element 300 may be disposed on the via layer 200.

[0188] The plurality of dams 410, 420, and 430 may include internal dams 410 and 420 disposed spaced apart from each other within each sub-pixel PXn and an external dam 430 disposed at a boundary between adjacent sub-pixels PXn.

[0189] When ink in which light-emitting elements 300 are dispersed is ejected using an inkjet printing apparatus during the manufacture of the display device 10, the outer bank 430 can function to prevent the ink from crossing the boundary of the sub-pixel PXn. However, it is not limited thereto.

[0190] The plurality of inner banks 410 and 420 may include a first inner bank 410 and a second inner bank 420 provided adjacent to the center of each sub-pixel PXn.

[0191] The first inner bank 410 and the second inner bank 420 are arranged to face each other while being spaced apart from each other. The first electrode 210 may be provided on the first inner bank 410, and the second electrode 220 may be provided on the second inner bank 420. Referring to Figure 21 and Figure 22 , it can be understood that the first electrode branch 210B is provided on the first inner bank 410, and the second electrode branch 220B is provided on the second inner bank 420.

[0192] The first inner bank 410 and the second inner bank 420 may extend in the second direction DR2 within each sub-pixel PXn. Although not shown in the drawings, the first inner bank 410 and the second inner bank 420 may extend in the second direction DR2 toward the sub-pixel PXn adjacent in the second direction DR2. However, the present disclosure is not limited thereto, and the first inner bank 410 and the second inner bank 420 may be respectively provided in each of the sub-pixels PXn to form a pattern on the entire surface of the display device 10. The plurality of banks 410, 420, and 430 may include polyimide (PI), but are not limited thereto.

[0193] Each of the first inner bank 410 and the second inner bank 420 may have a structure in which at least a part thereof protrudes above the via layer 200. Each of the first inner bank 410 and the second inner bank 420 may protrude above the plane on which the light-emitting element 300 is provided, and at least a part of the protruding portion may have a slope. The shape of the protruding portions of the first inner bank 410 and the second inner bank 420 is not particularly limited.

[0194] The plurality of electrodes 210 and 220 may be respectively provided on the via layer 200 and the inner banks 410 and 420. As described above, the electrodes 210 and 220 respectively include electrode bars 210S and 220S and electrode branches 210B and 220B. Figure 21 The line Xa-Xa' of Figure 21 is a line that intersects the first electrode bar 210S, Figure 21The line Xc-Xc' is a line that intersects the second electrode bar 220S. That is, the first electrode 210 disposed in the region Xa-Xa' can be understood as the first electrode bar 210S, the first electrode 210 and the second electrode 220 disposed in the region Xb-Xb' can be respectively understood as the first electrode branch 210B and the second electrode branch 220B, and the second electrode 220 disposed in the region Xc-Xc' can be understood as the second electrode bar 220S. The first electrode bar 210S and the first electrode branch 210B can form the first electrode 210, and the second electrode bar 220S and the second electrode branch 220B can form the second electrode 220. Figure 22 Some regions of the first electrode 210 can be disposed on the via hole layer 200, and some other regions of the first electrode 210 and the second electrode 220 can be respectively disposed on the first inner dam 410 and the second inner dam 420. As described above, the first electrode bar 210S of the first electrode 210 and the second electrode bar 220S of the second electrode 220 can extend in the first direction DR1, and the first inner dam 410 and the second inner dam 420 can extend in the second direction DR2 to be disposed in the sub-pixels PXn adjacent in the second direction DR2. Although not shown in the drawings, the first electrode bar 210S of the first electrode 210 and the second electrode bar 220S of the second electrode 220 extending in the first direction DR1 can partially overlap with the first inner dam 410 and the second inner dam 420, respectively. However, the present disclosure is not limited thereto, and the first electrode bar 210S and the second electrode bar 220S may not overlap with the first inner dam 410 and the second inner dam 420, respectively. Figure 22 The via hole layer 200 can be provided with a first electrode contact hole CNTD formed through the via hole layer 200 to expose a part of the first drain electrode 123 of the first transistor 120. The first electrode 210 can be in contact with the first drain electrode 123 through the first electrode contact hole CNTD. The first electrode 210 can be electrically connected to the first drain electrode 123 of the first transistor 120 to receive a preset electrical signal therefrom. Figure 22 The second electrode bar 220S of the second electrode 220 can extend in one direction so as to be also disposed in a non-emitting region where the light emitting element 300 is not provided. The via hole layer 200 can be provided with a second electrode contact hole CNTS formed through the via hole layer 200 to expose a part of the power supply electrode 162. The second electrode 220 can be in contact with the power supply electrode 162 through the second electrode contact hole CNTS. The second electrode 220 can be electrically connected to the power supply electrode 162 to receive a preset electrical signal from the power supply electrode 162.

[0195] Some regions of the first electrode 210 and the second electrode 220 can be disposed on the via hole layer 200, and some other regions of the first electrode 210 and the second electrode 220 can be respectively disposed on the first inner dam 410 and the second inner dam 420. As described above, the first electrode bar 210S of the first electrode 210 and the second electrode bar 220S of the second electrode 220 can extend in the first direction DR1, and the first inner dam 410 and the second inner dam 420 can extend in the second direction DR2 to be disposed in the sub-pixels PXn adjacent in the second direction DR2. Although not shown in the drawings, the first electrode bar 210S of the first electrode 210 and the second electrode bar 220S of the second electrode 220 extending in the first direction DR1 can partially overlap with the first inner dam 410 and the second inner dam 420, respectively. However, the present disclosure is not limited thereto, and the first electrode bar 210S and the second electrode bar 220S may not overlap with the first inner dam 410 and the second inner dam 420, respectively.

[0196] The via hole layer 200 can be provided with a first electrode contact hole CNTD formed through the via hole layer 200 to expose a part of the first drain electrode 123 of the first transistor 120. The first electrode 210 can be in contact with the first drain electrode 123 through the first electrode contact hole CNTD. The first electrode 210 can be electrically connected to the first drain electrode 123 of the first transistor 120 to receive a preset electrical signal therefrom.

[0197] The second electrode bar 220S of the second electrode 220 can extend in one direction so as to be also disposed in a non-emitting region where the light emitting element 300 is not provided. The via hole layer 200 can be provided with a second electrode contact hole CNTS formed through the via hole layer 200 to expose a part of the power supply electrode 162. The second electrode 220 can be in contact with the power supply electrode 162 through the second electrode contact hole CNTS. The second electrode 220 can be electrically connected to the power supply electrode 162 to receive a preset electrical signal from the power supply electrode 162.

[0198] Some regions of the first electrode 210 and the second electrode 220, for example, the first electrode branch 210B and the second electrode branch 220B can be disposed on the first inner bank 410 and the second inner bank 420, respectively. The first electrode branch 210B of the first electrode 210 can be disposed to cover the first inner bank 410, and the second electrode branch 220B of the second electrode 220 can be disposed to cover the second inner bank 420. Since the first inner bank 410 and the second inner bank 420 are disposed at the center of each sub-pixel PXn while being spaced apart from each other, the first electrode branch 210B and the second electrode branch 220B can also be spaced apart from each other. A plurality of light-emitting elements 300 can be disposed in the region between the first electrode 210 and the second electrode 220, that is, in the space where the first electrode branch 210B and the second electrode branch 220B are disposed to face each other and have a gap therebetween.

[0199] Each of the electrodes 210 and 220 can include a transparent conductive material. For example, each of the electrodes 210 and 220 can include materials such as indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO), but is not limited thereto. In some embodiments, each of the electrodes 210 and 220 can include a conductive material having a high reflectivity. For example, each of the electrodes 210 and 220 can include a metal such as silver (Ag), copper (Cu), or aluminum (Al) as the material having a high reflectivity. In this case, the light incident on each of the electrodes 210 and 220 can be reflected to irradiate in the upward direction of each sub-pixel PXn.

[0200] In addition, each of the electrodes 210 and 220 can have a structure in which at least one transparent conductive material and at least one metal layer having a high reflectivity are stacked, or can be formed as a single layer including them. In an embodiment, each of the electrodes 210 and 220 can have a stacked structure of ITO / silver (Ag) / ITO / IZO, or can be made of an alloy including aluminum (Al), nickel (Ni), and lanthanum (La). However, it is not limited thereto.

[0201] The first insulating layer 510 is disposed on the via layer 200, the first electrode 210, and the second electrode 220. The first insulating layer 510 is disposed to partially cover the first electrode 210 and the second electrode 220. The first insulating layer 510 may be disposed to cover most of the top surfaces of the first electrode 210 and the second electrode 220 while leaving a part of the first electrode 210 and the second electrode 220 exposed. The first insulating layer 510 may be disposed such that some of the top surfaces of the first electrode 210 and the second electrode 220, for example, a part of the top surface of the first electrode branch 210B disposed on the first inner bank 410 and a part of the top surface of the second electrode branch 220B disposed on the second inner bank 420, are exposed. That is, the first insulating layer 510 may be substantially formed on the entire surface of the via layer 200, but it may have openings through which the first electrode 210 and the second electrode 220 are partially exposed. The openings of the first insulating layer 510 may be positioned to expose the relatively flat top surfaces of the first electrode 210 and the second electrode 220 therethrough.

[0202] In an embodiment, the first insulating layer 510 may be formed to have a step such that a part of its top surface is recessed between the first electrode 210 and the second electrode 220. In some embodiments, the first insulating layer 510 may include an inorganic insulating material, and the part of the top surface of the first insulating layer 510 that is disposed to cover the first electrode 210 and the second electrode 220 may be recessed due to the steps of the members disposed thereunder. The light-emitting element 300 disposed on the first insulating layer 510 between the first electrode 210 and the second electrode 220 may form an empty space with respect to the recessed top surface of the first insulating layer 510. The light-emitting element 300 may be disposed to be partially spaced apart from the top surface of the first insulating layer 510 with a gap therebetween, and the gap may be filled with a material for forming the second insulating layer 520, which will be described later.

[0203] However, the present disclosure is not limited thereto. The first insulating layer 510 may be formed to have a flat top surface such that the light-emitting element 300 is disposed thereon. The top surface may extend in one direction toward the first electrode 210 and the second electrode 220 and may terminate at the inclined side surfaces of the first electrode 210 and the second electrode 220. That is, the first insulating layer 510 may be disposed in a region where the electrodes 210 and 220 respectively overlap the inclined side surfaces of the first inner bank 410 and the second inner bank 420. The contact electrodes 261 and 262, which will be described later, may contact the exposed regions of the first electrode 210 and the second electrode 220 and may smoothly contact the ends of the light-emitting element 300 on the flat top surface of the first insulating layer 510.

[0204] The first insulating layer 510 can protect the first electrode 210 and the second electrode 220 while insulating them from each other. In addition, it is possible to prevent the light-emitting element 300 disposed on the first insulating layer 510 from being damaged by direct contact with other components. However, the shape and structure of the first insulating layer 510 are not limited thereto.

[0205] The light-emitting element 300 can be disposed on the first insulating layer 510 between the electrodes 210 and 220. For example, at least one light-emitting element 300 can be disposed on the first insulating layer 510 disposed between the electrode branches 210B and 220B. However, it is not limited thereto, and at least some of the light-emitting elements 300 in each sub-pixel PXn can be placed in an area outside the area between the electrode branches 210B and 220B. In addition, the light-emitting element 300 can be disposed such that some of its areas overlap with the electrodes 210 and 220. The light-emitting element 300 can be disposed on the facing ends of the first electrode branch 210B and the second electrode branch 220B, and can be electrically connected to the electrodes 210 and 220 via the contact electrodes 261 and 262.

[0206] As described above, the light-emitting elements 300 configured to emit lights L1, L2, and L3 having different wavelengths can be disposed in each of the sub-pixels PXn. Although the drawings only show the first sub-pixel PX1 in which the first light-emitting element 301 is disposed, the above-described structures and features can also be applied to the second sub-pixel PX2 and the third sub-pixel PX3.

[0207] In addition, the light-emitting element 300 can include a plurality of layers arranged in a direction horizontal to the via hole layer 200. The light-emitting element 300 of the display device 10 according to one embodiment can include a first semiconductor layer 310, a second semiconductor layer 320, and an active layer 360, and these layers can be sequentially arranged in a direction horizontal to the via hole layer 200. However, the present disclosure is not limited thereto. The order in which the plurality of layers of the light-emitting element 300 are arranged can be opposite to the order mentioned above. In some cases, if the light-emitting element 300 has a different structure, the plurality of layers can be arranged in a direction perpendicular to the via hole layer 200.

[0208] In addition, the light-emitting element 300 according to one embodiment can further include a first electrode layer 371 and a second electrode layer 372, which can be in contact with the second contact electrode 262 and the first contact electrode 261 to be described later, respectively. The first contact electrode 261 can be in contact with the second electrode layer 372 of the light-emitting element 300 and the first surface (e.g., Figure 16 380S_1 in Figure 15contact with the 380C2_1) in it. The second contact electrode 262 can be in contact with the first electrode layer 371 and the first surface of the insulating film 380 adjacent to the first electrode layer 371 (e.g., Figure 16 the 380S_1) and the second surface (e.g., Figure 16 contact with the 380C1_1) in it. However, the present disclosure is not limited thereto, and the display device 10 may include a light-emitting element 300 in which the first electrode layer 371 is in contact with the first contact electrode 261 and the second electrode layer 372 is in contact with the second contact electrode 262. The light-emitting element 300 according to one embodiment may have a shape extending in one direction, and the length of the first semiconductor layer 310 may be longer than the length of the second semiconductor layer 320. The first electrode layer 371 may be disposed farther from the active layer 360 than the second electrode layer 372. As previously referred to Figure 15 and Figure 16 described, the end surface of the insulating film 380_1 surrounding the first electrode layer 371_1 (where the first electrode layer 371_1 is positioned away from the active layer 360_1 of the light-emitting element 300_1) may have a partially curved shape. As Figure 22 shown, in the light-emitting element 300 disposed on the first insulating layer 510, the insulating film 380 at one end facing the first electrode 210 may be formed to have a flat end surface, while the insulating film 380 at the other end facing the second electrode 220 may be formed to have a curved end surface. However, the present disclosure is not limited thereto, and the light-emitting element 300 may be disposed such that the curved portion of the insulating film 380 faces the first electrode 210. That is, the display device 10 may further include a light-emitting element 300 disposed such that the first electrode layer 371 faces the first electrode 210.

[0209] The second insulating layer 520 may be partially disposed on the light-emitting element 300. The second insulating layer 520 may be disposed to partially surround the outer surface of the light-emitting element 300. The second insulating layer 520 may protect the light-emitting element 300 while also performing the function of fixing the light-emitting element 300 during the manufacturing process of the display device 10. In addition, in an embodiment, some of the material of the second insulating layer 520 may be disposed between the bottom surface of the light-emitting element 300 and the first insulating layer 510. As described above, the second insulating layer 520 may be formed to fill the gap formed during the manufacturing process of the display device 10 between the light-emitting element 300 and the first insulating layer 510. Therefore, the second insulating layer 520 may be formed to surround the outer surface of the light-emitting element 300. However, the present disclosure is not limited thereto.

[0210] In a plan view, the second insulating layer 520 may extend in a second direction DR2 between the first electrode branch 210B and the second electrode branch 220B. As an example, in a plan view, the second insulating layer 520 may have an island or linear shape on the via layer 200.

[0211] The contact electrodes 261 and 262 are disposed on the electrodes 210 and 220 and the second insulating layer 520. The first contact electrode 261 and the second contact electrode 262 may be disposed spaced apart from each other on the second insulating layer 520. The second insulating layer 520 may insulate the first contact electrode 261 and the second contact electrode 262 from each other so that they do not contact each other directly.

[0212] Although not shown in the drawings, in a plan view, the plurality of contact electrodes 261 and 262 may extend in the second direction DR2 and be spaced apart from each other in the first direction DR1. The contact electrodes 261 and 262 may contact at least one end of the light-emitting element 300, and the contact electrodes 261 and 262 may be electrically connected to the first electrode 210 or the second electrode 220 to receive an electrical signal. The contact electrodes 261 and 262 may include a first contact electrode 261 and a second contact electrode 262. The first contact electrode 261 may be disposed on the first electrode branch 210B to contact one end of the light-emitting element 300, and the second contact electrode 262 may be disposed on the second electrode branch 220B to contact the other end of the light-emitting element 300.

[0213] The first contact electrode 261 may contact the exposed area of the first electrode 210 on the first inner bank 410, and the second contact electrode 262 may contact the exposed area of the second electrode 220 on the second inner bank 420. The contact electrodes 261 and 262 can respectively transfer the electrical signals transmitted from the electrodes 210 and 220 to the light-emitting element 300.

[0214] The contact electrodes 261 and 262 may include a conductive material. For example, they may include ITO, IZO, ITZO, aluminum (Al), etc. However, it is not limited thereto.

[0215] The passivation layer 550 may be disposed on the first contact electrode 261, the second contact electrode 262, and the second insulating layer 520. The passivation layer 550 may serve to protect the components disposed on the via layer 200 from the external environment.

[0216] Each of the above-mentioned first insulating layer 510, second insulating layer 520, and passivation layer 550 may include an inorganic insulating material or an organic insulating material. In an embodiment, the first insulating layer 510, the second insulating layer 520, and the passivation layer 550 may include, for example, silicon oxide (SiO x ), silicon nitride (SiN x) Inorganic insulating materials such as silicon oxynitride (SiO x N y ), aluminum oxide (Al2O3), aluminum nitride (AlN), etc. The first insulating layer 510, the second insulating layer 520, and the passivation layer 550 may include organic insulating materials such as acrylic resin, epoxy resin, phenolic resin, polyamide resin, polyimide resin, unsaturated polyester resin, polyphenylene resin, polyphenylene sulfide resin, benzocyclobutene, cardo resin, silicone resin, silsesquioxane resin, polymethyl methacrylate, polycarbonate, or polycarbonate synthetic resin. However, it is not limited thereto.

[0217] Meanwhile, the display device 10 may further include a greater number of insulating layers. According to one embodiment, the display device 10 may further include a third insulating layer 530_1 (see Figure 23 ) provided to protect the first contact electrode 261.

[0218] Figure 23 is a cross-sectional view of a display device according to another embodiment.

[0219] Referring to Figure 23 , the display device 10_1 according to the embodiment may further include a third insulating layer 530_1 provided on the first contact electrode 261_1. The display device 10_1 of the present embodiment is different from the display device 10 of Figure 22 in that it further includes a third insulating layer 530_1, and at least a part of the second contact electrode 262_1 is provided on the third insulating layer 530_1. In the following description, redundant descriptions will be omitted and the focus will be on the differences.

[0220] Figure 23 The display device 10_1 of may include a third insulating layer 530_1 provided on the first contact electrode 261_1 and for electrically insulating the first contact electrode 261_1 and the second contact electrode 262_1 from each other. The third insulating layer 530_1 may be provided to cover the first contact electrode 261_1, but may also be provided so as not to overlap some regions of the light-emitting element 300, such that the light-emitting element 300 can be connected to the second contact electrode 262_1. The third insulating layer 530_1 may partially contact the first contact electrode 261_1 and the second insulating layer 520_1 on the top surface of the second insulating layer 520_1. The third insulating layer 530_1 may be provided to cover one end of the first contact electrode 261_1 on the second insulating layer 520_1. Therefore, the third insulating layer 530_1 can protect the first contact electrode 261_1 while serving to insulate the first contact electrode 261_1 from the second contact electrode 262_1.

[0221] The side surface of the third insulating layer 530_1 on the side where the second contact electrode 262_1 is located may be aligned with one side surface of the second insulating layer 520_1. However, it is not limited thereto. In some embodiments, the third insulating layer 530_1 may include an inorganic insulating material in the same manner as the first insulating layer 510.

[0222] The first contact electrode 261_1 may be disposed between the first electrode 210_1 and the third insulating layer 530_1, and the second contact electrode 262_1 may be disposed on the third insulating layer 530_1. The second contact electrode 262_1 may be in partial contact with the first insulating layer 510_1, the second insulating layer 520_1, the third insulating layer 530_1, the second electrode 220_1, and the light-emitting element 300. One end of the second contact electrode 262_1 on the side where the first electrode 210_1 is located may be disposed on the third insulating layer 530_1.

[0223] The passivation layer 550_1 may be disposed on the third insulating layer 530_1 and the second contact electrode 262_1 to protect them. The banks 410_1 and 420_1 are similar to those of Figure 22 Those will be omitted in the following redundant description.

[0224] On the other hand, the first electrode 210 and the second electrode 220 of the display device 10 do not have to have a shape extending in one direction. The shapes of the first electrode 210 and the second electrode 220 of the display device 10 are not particularly limited as long as they are spaced apart from each other to provide a space therebetween in which the light-emitting element 300 is disposed.

[0225] Figure 24 is a plan view showing a pixel of a display device according to still another embodiment.

[0226] Referring to Figure 24 , at least some regions of the first electrode 210_2 and the second electrode 220_2 of the display device 10_2 according to the embodiment have a curved shape, and the curved region of the first electrode 210_2 may face the curved region of the second electrode 220_2 while being spaced apart from each other. The display device 10_2 according to the present embodiment is different from the display device 10 of Figure 21 in that the shapes of the first electrode 210_2 and the second electrode 220_2 are different from those of the display device 10. In the following description, redundant descriptions will be omitted and the focus will be on the differences.

[0227] Figure 24The first electrode 210_2 of the display device 10_2 may include a plurality of holes HOL. For example, as shown in the drawings, the first electrode 210_2 may include a first hole HOL1, a second hole HOL2, and a third hole HOL3 arranged in the second direction DR2. However, the embodiments are not limited thereto, and the first electrode 210_2 may include a greater number of holes HOL, a smaller number of holes HOL, or even a single hole HOL. Hereinafter, an example in which the first electrode 210_2 includes the first hole HOL1, the second hole HOL2, and the third hole HOL3 will be described.

[0228] In an embodiment, the first hole HOL1, the second hole HOL2, and the third hole HOL3 may have a circular shape in a plan view. Accordingly, the first electrode 210_2 may have a curved region formed by the holes HOL and face the second electrode 220_2 in these curved regions. However, this is merely exemplary, and the present disclosure is not limited thereto. The first hole HOL1, the second hole HOL2, and the third hole HOL3 are not particularly limited in shape as long as they can provide a space for accommodating the second electrode 220_2 therein. For example, in a plan view, the hole HOL may have an elliptical shape, a polygonal shape such as a rectangle, or the like.

[0229] The number of the second electrodes 220_2 may be plural, and the plural second electrodes 220_2 may be disposed in each sub-pixel PXn. For example, in each sub-pixel PXn, three second electrodes 220_2 may be disposed in each sub-pixel PXn corresponding to the first hole HOL1, the second hole HOL2, and the third hole HOL3 of the first electrode 210_2. The second electrodes 220_2 may be respectively disposed in the first hole HOL1, the second hole HOL2, and the third hole HOL3 surrounded by the first electrode 210_2.

[0230] In an embodiment, the hole HOL of the first electrode 210_2 may have a curved surface, and each second electrode 220_2 disposed in the corresponding hole HOL of the first electrode 210_2 may also have a curved surface and be disposed to face the first electrode 210_2 with a gap therebetween. As Figure 24 shown, the first electrode 210_2 may include a hole HOL having a circular shape in a plan view, and the second electrode 220_2 may have a circular shape in a plan view. The curved surface of the region of the first electrode 210_2 in which each hole HOL is formed may face the curved outer surface of a corresponding one of the second electrodes 220_2 with a gap therebetween. For example, the first electrode 210_2 may be disposed to surround the outer surface of the second electrode 220_2.

[0231] As described above, the light-emitting element 300 may be disposed between the first electrode 210_2 and the second electrode 220_2. The display device 10_2 according to an embodiment may include a second electrode 220_2 having a circular shape and a first electrode 210_2 disposed to surround the second electrode 220_2, and a plurality of light-emitting elements 300 may be arranged along the outer surface of the second electrode 220_2. As described above, since the light-emitting element 300 has a shape extending in one direction, the light-emitting elements 300 arranged along the curved outer surface of the second electrode 220_2 in each sub-pixel PXn may be arranged such that their extension directions point in different directions. Depending on the direction in which the extension direction of the light-emitting element 300 points, each sub-pixel PXn may have many different light-emitting directions. In the display device 10_2 according to an embodiment, by setting the first electrode 210_2 and the second electrode 220_2 to have a curved shape, the light-emitting elements 300 disposed therebetween may be oriented in different directions, and the lateral visibility of the display device 10_2 may be improved. The light-emitting elements 301_2, 302_2, and 303_2 are the same as those described above and will not be described in detail herein.

[0232] At the end of the detailed description, those skilled in the art will understand that many changes and modifications can be made to the preferred embodiments without substantially departing from the principles of the present invention. Therefore, the preferred embodiments of the present invention disclosed are used only in an illustrative and descriptive sense and not for the purpose of limitation.

Claims

1. A light-emitting element having a shape extending in one direction, comprising: A first semiconductor layer and a second semiconductor layer; An active layer disposed between the first semiconductor layer and the second semiconductor layer in the one direction; A first electrode layer disposed on the other surface of the first semiconductor layer opposite to the one surface of the first semiconductor layer facing the active layer; A second electrode layer disposed on the other surface of the second semiconductor layer opposite to the one surface of the second semiconductor layer facing the active layer; And An insulating film surrounding at least a part of the side surfaces of the first electrode layer and the second electrode layer and the side surface of the active layer, Wherein, in the insulating film, a first region surrounding the side surface of the active layer has a thickness in a direction perpendicular to the one direction greater than a thickness of a second region surrounding the side surface of the first electrode layer in a direction perpendicular to the one direction, Wherein a thickness of a third region of the insulating film adjacent to the side surface of the second electrode layer in a direction perpendicular to the one direction is greater than the thickness of the second region adjacent to the side surface of the first electrode layer of the insulating film.

2. The light-emitting element according to claim 1, wherein, The insulating film includes: A first surface extending in the one direction; A second surface connected between the first surface and an end face of the first electrode layer; and A third surface connected between the first surface and an end face of the second electrode layer.

3. The light-emitting element according to claim 2, wherein, In a plan view, at least a part of the second surface has a curved shape.

4. The light-emitting element according to claim 3, wherein, The third surface is formed as a flat surface and is located in the same plane as one surface of the second electrode layer.

5. The light-emitting element according to claim 4, wherein, A distance between the active layer and the first electrode layer is greater than a distance between the active layer and the second electrode layer.

6. The light-emitting element according to claim 4, wherein, In the plan view, a width of the one surface of the first semiconductor layer is greater than a width of the other surface of the first semiconductor layer.

7. The light-emitting element according to claim 2, wherein, The active layer emits a first light having a central wavelength band in a range from 450 nm to 495 nm.

8. The light-emitting element according to claim 2, further comprising: A third semiconductor layer disposed between the first semiconductor layer and the active layer; A fourth semiconductor layer disposed between the active layer and the second semiconductor layer; And A fifth semiconductor layer disposed between the fourth semiconductor layer and the second semiconductor layer.

9. The light-emitting element according to claim 8, wherein, The active layer emits a second light having a central wavelength band in a range from 620 nm to 750 nm.

10. A method for manufacturing a light-emitting element, comprising: Preparing a semiconductor structure formed on a bottom substrate and forming a support layer on a first surface of the semiconductor structure to separate the semiconductor structure from the bottom substrate, wherein the semiconductor structure includes a first semiconductor layer, an active layer formed on the first semiconductor layer, and a second semiconductor layer formed on the active layer; Form a first electrode layer on a second surface of the semiconductor structure separated from the underlying substrate, and etch the first electrode layer and the semiconductor structure in a first direction perpendicular to the support layer to form a semiconductor crystal; Form an insulating film around a side surface of the semiconductor crystal, wherein, in the insulating film, a first region around a side surface of the active layer has a greater thickness in a second direction perpendicular to the first direction than a second region around a side surface of the first electrode layer in the second direction, and Separate the semiconductor crystal, on which the insulating film is formed, from the support layer wherein the semiconductor structure further includes a second electrode layer formed on the second semiconductor layer, wherein the first surface is a top surface of the second electrode layer, and wherein a third region of the insulating film adjacent to a side surface of the second electrode layer has a greater thickness in a direction perpendicular to the first direction than the thickness of the second region of the insulating film adjacent to the side surface of the first electrode layer.

11. The manufacturing method according to claim 10, wherein, The underlying substrate includes a base substrate and a separation layer formed on the base substrate, and Separating the semiconductor structure includes: separating the semiconductor structure from the base substrate by removing the separation layer.

12. The manufacturing method according to claim 10, wherein The second surface of the semiconductor structure is a bottom surface of the first semiconductor layer, and Forming the semiconductor crystal includes: etching the semiconductor structure in a direction from a bottom surface of the first electrode layer to a top surface of the second electrode layer.

13. The manufacturing method according to claim 12, wherein, Forming the insulating film includes: Forming an insulating coating film around an outer surface of the semiconductor crystal; and Removing the insulating coating film to expose the bottom surface of the first electrode layer.

14. The manufacturing method according to claim 13, wherein, The insulating film includes a third surface extending in one direction, a fourth surface located between the third surface and an end surface of the first electrode layer, and a fifth surface located between the third surface and an end surface of the second electrode layer, and At least a part of the fourth surface has a curved shape.

15. A display device, including a first pixel and a second pixel, includes: A substrate; A first electrode disposed on the substrate; A second electrode disposed on the substrate and spaced apart from the first electrode; And At least one light-emitting element disposed between the first electrode and the second electrode, wherein the light-emitting element includes: A first semiconductor layer and a second semiconductor layer; An active layer disposed between the first semiconductor layer and the second semiconductor layer in a first direction; A first electrode layer disposed on another surface of the first semiconductor layer opposite to a surface of the first semiconductor layer facing the active layer; A second electrode layer disposed on another surface of the first semiconductor layer opposite to a surface of the second semiconductor layer facing the active layer; and An insulating film surrounding at least a part of side surfaces of the first electrode layer and the second electrode layer and a side surface of the active layer Among them, in the insulating film, the thickness of a first region surrounding the side surface of the active layer in a second direction perpendicular to the first direction is greater than the thickness of a second region surrounding the side surface of the first electrode layer in the second direction. Among them, the thickness of a third region of the insulating film adjacent to the side surface of the second electrode layer in a direction perpendicular to the first direction is greater than the thickness of the second region of the insulating film adjacent to the side surface of the first electrode layer.

16. The display device according to claim 15, wherein, The insulating film includes a first surface extending in the first direction, a second surface located between the first surface and the end face of the first electrode layer, and a third surface located between the first surface and the end face of the second electrode layer, and At least a part of the second surface has a curved shape.

17. The display device according to claim 16, further comprising: A first contact electrode in contact with the first electrode and the second electrode layer; And A second contact electrode in contact with the second electrode and the first electrode layer.

18. The display device according to claim 17, wherein, The light-emitting element includes: A first light-emitting element disposed in the first pixel; and A second light-emitting element disposed in the second pixel, and The active layer of the first light-emitting element emits first light having a center wavelength band in the range from 450 nm to 495 nm.

19. The display device according to claim 18, wherein, The second light-emitting element further includes a third semiconductor layer disposed between the first semiconductor layer and the active layer, a fourth semiconductor layer disposed between the active layer and the second semiconductor layer, and a fifth semiconductor layer disposed between the fourth semiconductor layer and the second semiconductor layer, and The active layer of the second light-emitting element emits second light having a center wavelength band in the range from 620 nm to 750 nm.

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