Light emitting element and display device including the same

Abstract

Provided are a light-emitting element and a display device including the light-emitting element. The light-emitting element includes: a first conductive semiconductor doped with a first polarity; a second conductive semiconductor doped with a second polarity opposite to the first polarity; an active layer disposed between the first conductive semiconductor and the second conductive semiconductor; and an insulating film, the insulating film at least surrounding a side of the active layer, wherein the insulating film includes an insulating coating film and at least one light conversion particle disposed on at least a portion of the insulating coating film.

Description

Technical Field

[0001] The present invention relates to a light emitting element and a display device including the light emitting element. Background Art

[0002] As multimedia develops, display devices become more and more important. In response to the development, various types of display devices, such as organic light emitting diode (OLED) display devices, liquid crystal display (LCD) devices, and the like, are being used.

[0003] The device for displaying an image of the display device includes a display panel such as an OLED panel or an LCD panel. Among the above panels, the light-emitting display panel may include a light-emitting element. For example, the LED includes an OLED using an organic material as a fluorescent material and an inorganic LED using an inorganic material as a fluorescent material.

[0004] Compared to OLED, inorganic LEDs using inorganic semiconductors as fluorescent materials have durability in high temperature environments and have the advantage of high efficiency of blue light. In addition, even in the manufacturing process that has been pointed out as a limitation of conventional inorganic LED elements, a transfer method using dielectrophoresis (DEP) has been developed. Therefore, research on inorganic LEDs having excellent durability and excellent efficiency compared to OLED is being conducted. Summary of the invention

[0005] Technical issues

[0006] The present invention is directed to a light emitting element comprising a semiconductor crystal and an insulating film surrounding the semiconductor crystal, wherein the insulating film comprises an insulating coating film and scattering particles arranged on the insulating coating film to provide the light emitting element from which emitted light travels in one direction.

[0007] In addition, the present invention is directed to providing a display device including a light emitting element and having improved top emission efficiency using the light emitting element disposed horizontally.

[0008] It should be noted that the objects of the present invention are not limited to the above objects, and other objects of the present invention will be apparent to those skilled in the art through the following description.

[0009] Technical Solution

[0010] According to an embodiment, a light-emitting element includes: a first conductive semiconductor doped with a first polarity; a second conductive semiconductor doped with a second polarity opposite to the first polarity; an active layer arranged between the first conductive semiconductor and the second conductive semiconductor; and an insulating film, the insulating film at least surrounding the side surface of the active layer, wherein the insulating film includes an insulating coating film and at least one light conversion particle arranged on at least a portion of the insulating coating film.

[0011] The first conductive type semiconductor, the active layer, and the second conductive type semiconductor may be arranged in a first direction, and the active layer emits light.

[0012] The light emitted from the active layer may include first emitted light propagating in a first direction toward both ends of the light emitting element and second emitted light propagating in a second direction different from the first direction.

[0013] At least a portion of the second emitted light may be incident on at least one light conversion particle and emitted from the active layer in a direction perpendicular to the first direction.

[0014] In the light emitting element, an amount of light emitted in a direction perpendicular to the first direction may be greater than an amount of light emitted in the first direction.

[0015] The at least one light conversion particle may include at least one of first light conversion particles that scatter incident light emitted from the active layer and second light conversion particles that amplify the intensity of the incident light.

[0016] The first light conversion particles may include silicon nitride (Si 3 N 4 ), silicon dioxide (SiO 2 ), aluminum oxide (Al 2 O 3 ), hafnium oxide (HfO 2 ), yttrium oxide (Y 2 O 3 ) and titanium dioxide (TiO 2 ) at least one of.

[0017] The diameter of the first light conversion particles may be in the range of 100 nm to 2000 nm.

[0018] The second light conversion particles may include at least one of gold (Au), silver (Ag), copper (Cu), and aluminum (Al).

[0019] The diameter of the second light conversion particles may be in the range of 10 nm to 300 nm.

[0020] The light emitting element may further include a particle region defined as a region in which at least one light conversion particle is disposed on the insulating coating film, wherein the particle region may be disposed on the insulating coating film to overlap at least the active layer.

[0021] The particle region may have a shape extending in the first direction.

[0022] A ratio of an area of ​​the particle region to an area of ​​an outer surface of the insulating coating film may be in a range of 0.5 to 0.6.

[0023] The light emitting element may have a length in the range of 4 μm to 7 μm and an aspect ratio in the range of 1.2 to 100.

[0024] According to another embodiment, a display device includes: a base layer; a first electrode and a second electrode, the first electrode and the second electrode being separated from each other along a first direction on the base layer; and at least one light-emitting element arranged between the first electrode and the second electrode, wherein the at least one light-emitting element includes a semiconductor crystal and an insulating film, the semiconductor crystal has a shape extending in the first direction and is configured to emit light within a specific wavelength range, the insulating film is configured to surround a side surface of the semiconductor crystal, and the insulating film includes an insulating coating film and at least one light-conversion particle arranged on at least a portion of the insulating coating film.

[0025] At least some of the light emitted from the semiconductor crystal may be incident on at least one light converting particle and emitted in a direction different from the first direction.

[0026] In at least one light emitting element, an amount of light emitted in a direction perpendicular to the first direction may be greater than an amount of light emitted in the first direction.

[0027] The at least one light conversion particle may include at least one of first light conversion particles that scatter incident light and second light conversion particles that amplify the intensity of the incident light.

[0028] The at least one light emitting element may include a first light emitting element and a second light emitting element; and the first light emitting element and the second light emitting element may have different separation distances from the base layer in a second direction perpendicular to the base layer.

[0029] The display device may further include: a first contact electrode in contact with the first electrode and one end of the at least one light emitting element; and a second contact electrode in contact with the second electrode and the other end of the at least one light emitting element.

[0030] Details of other embodiments are included in the detailed description and accompanying drawings.

[0031] Beneficial Effects

[0032] The light-emitting element according to the embodiment includes light conversion particles, so that the light emitted from the active layer cannot be reflected from the insulating coating film and can be emitted to the outside through the light conversion particles. The light conversion particles can scatter the light incident from the active layer or amplify the intensity of the incident light to increase the amount of light emitted from the light-emitting element in one direction.

[0033] In addition, the display device according to the embodiment may include a light emitting element in which the amount of light emitted in a direction perpendicular to the extension direction can be increased. Therefore, the display device includes a light emitting element arranged in a horizontal direction, and thus the top emission efficiency can be improved.

[0034] The effects according to the embodiments are not limited to the contents exemplified above, and more various effects are included in the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram showing a light emitting element according to an embodiment.

[0036] Figure 2 yes Figure 1 An enlarged view of part A of FIG.

[0037] Figure 3 is a cross-sectional view showing a light emitting element according to an embodiment.

[0038] Figure 4 is a schematic diagram illustrating a propagation direction of light emitted from a light emitting element according to an embodiment.

[0039] Figure 5 yes Figure 4 An enlarged view of part B.

[0040] Figure 6 is an enlarged view showing the outer surface of a light emitting element according to another embodiment.

[0041] Figure 7 It is shown from Figure 6 Schematic diagram of the propagation of light emitted by a light-emitting element.

[0042] Figures 8 to 10 FIG. 1 is a schematic diagram showing that a light emitting element is disposed on a substrate according to an embodiment.

[0043] Fig.11 is a plan view showing a display device according to an embodiment.

[0044] Fig.12 is along Fig.11 A cross-sectional view taken along line II-II'.

[0045] Fig.13 is a schematic cross-sectional view showing a display device according to another embodiment.

[0046] Fig.14 is a schematic diagram showing a light emitting element according to another embodiment. DETAILED DESCRIPTION

[0047] 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 present invention may be implemented in different forms and should not be construed as being limited to the embodiments set forth herein. Instead, 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.

[0048] 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 refer to the same components.

[0049] 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 element. 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.

[0050] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0051] Figure 1 is a schematic diagram showing a light emitting element according to an embodiment.

[0052] The light emitting element 300 may be a light emitting diode (LED), specifically, the light emitting element 300 may be an inorganic LED having a micrometer unit size or a nanometer unit size and made of an inorganic material. In the case where the light emitting element 300 is an inorganic LED, when an electric field is formed in a specific direction between two electrodes opposite to each other, the inorganic LED may be disposed between two electrodes each having polarity. The light emitting element 300 may receive a predetermined electrical signal from the connected electrodes to emit light within a specific wavelength range.

[0053] The light emitting element 300 may include a semiconductor crystal doped with impurities of any conductivity type (eg, p-type or n-type). The semiconductor crystal may receive an electrical signal applied from an external power source and emit light within a specific wavelength range.

[0054] Reference Figure 1 According to an embodiment, the light emitting element 300 may include a first conductive semiconductor 310, a second conductive semiconductor 320, an active layer 330, and an insulating film 380. In addition, according to an embodiment, the light emitting element 300 may further include at least one conductive electrode layer 370. Figure 13. The light emitting element 300 is shown as including one conductive electrode layer 370, but the present invention is not limited thereto. In some cases, the light emitting element 300 may include a greater number of conductive electrode layers 370, or the conductive electrode layer 370 may be omitted. Even when the number of the conductive electrode layers 370 is changed or another structure is further included, the description of the light emitting element 300 to be performed below may be similarly applied.

[0055] In addition, in the present disclosure, the terms "first", "second", etc. are used to refer to corresponding components, but these terms are used to simply distinguish components from each other and do not necessarily refer to corresponding components. That is, components defined as first, second, etc. are not necessarily limited to specific structures or positions, and in some cases, other numbers may be assigned to components. Therefore, the numbers assigned to each component may be described through the accompanying drawings and the following description, and the first component mentioned below may be the second component within the technical concept of the present invention.

[0056] The light emitting element 300 may have a shape extending in one direction. The light emitting element 300 may have a shape of a nanorod, a nanowire, a nanotube, etc. In an embodiment, the light emitting element 300 may be a cylindrical shape or a rod shape. However, the shape of the light emitting element 300 is not limited thereto, and may have various shapes such as a regular hexahedron shape, a rectangular parallelepiped shape, a hexagonal column shape, etc. A plurality of semiconductors included in the light emitting element 300, which will be described below, may have a structure in which the semiconductors are sequentially arranged or stacked in one direction.

[0057] The light emitting element 300 according to one embodiment can emit light within a specific wavelength range. In an example, the active layer 330 can emit blue light with a central wavelength range ranging from 450nm to 495nm. However, the central wavelength range of blue light is not limited to the above range, and it should be understood that the central wavelength range includes all wavelength ranges that can be identified as blue in the art. In addition, the light emitted from the active layer 330 of the light emitting element 300 is not limited thereto, and the light can be green light with a central wavelength range ranging from 495nm to 570nm or red light with a central wavelength range ranging from 620nm to 750nm.

[0058] For reference Figure 1 The light emitting element 300 is described in detail. The first conductive semiconductor 310 may be, for example, an n-type semiconductor having a first conductive type. For example, when the light emitting element 300 emits light in a blue wavelength range, the first conductive semiconductor 310 may include an n-type semiconductor having a first conductive type. x Al y Ga 1-x-yN (0≤x≤1, 0≤y≤1, and 0≤x+y≤1) semiconductor material. For example, the semiconductor material may be one or more of InAlGaN, GaN, AlGaN, InGaN, AlN and InN doped with n-type. The first conductive semiconductor 310 may be doped with a first conductive dopant. For example, the first conductive dopant may be Si, Ge, Sn, etc. In an example, the first conductive semiconductor 310 may be n-GaN doped with n-type Si. The length of the first conductive semiconductor 310 may be in the range of 1.5μm to 5μm, but the present invention is not limited thereto.

[0059] The second conductive type semiconductor 320 is disposed on the active layer 330 to be described below. For example, the second conductive type semiconductor 320 may be a p-type semiconductor having a second conductive type. For example, when the light emitting element 300 emits light in a blue or green wavelength range, the second conductive type semiconductor 320 may include a semiconductor having an In x Al y Ga 1-x-y N (0≤x≤1, 0≤y≤1, and 0≤x+y≤1) semiconductor material. For example, the semiconductor material may be one or more of InAlGaN, GaN, AlGaN, InGaN, AlN and InN doped with p-type. The second conductive type semiconductor 320 may be doped with a second conductive type dopant. For example, the second conductive type dopant may be Mg, Zn, Ca, Se, Ba, etc. In an example, the second conductive type semiconductor 320 may be p-GaN doped with p-type Mg. The length of the second conductive type semiconductor 320 may be in the range of 0.08μm to 0.25μm, but the present invention is not limited thereto.

[0060] Meanwhile, in the drawings, although each of the first conductive type semiconductor 310 and the second conductive type semiconductor 320 is shown as being formed of one layer, the present invention is not limited thereto. In some cases, each of the first conductive type semiconductor 310 and the second conductive type semiconductor 320 may further include a greater number of layers, such as a cladding layer or a tensile strain barrier reduction (TSBR) layer, depending on the material of the active layer 330.

[0061] The active layer 330 is disposed between the first conductive type semiconductor 310 and the second conductive type semiconductor 320. The active layer 330 may include a material having a single quantum well structure or a multi-quantum well structure. When the active layer 330 includes a material having a multi-quantum well structure, the active layer 330 may have a structure in which a plurality of quantum layers and a plurality of well layers are alternately stacked. In response to an electrical signal applied through the first conductive type semiconductor 310 and the second conductive type semiconductor 320, the active layer 330 may emit light due to the recombination of electron-hole pairs. For example, when the active layer 330 emits light in the blue wavelength range, the active layer 330 may include materials such as AlGaN, AlInGaN, etc. Specifically, when the active layer 330 has a multi-quantum well structure in which quantum layers and well layers are alternately stacked, the quantum layers may include materials such as AlGaN or AlInGaN, and the well layers may include materials such as GaN or AlInN. In the example, the active layer 330 includes AlGaInN as a quantum layer and AlInN as a well layer. As described above, the active layer 330 may emit blue light having a central wavelength ranging from 450 nm to 495 nm.

[0062] However, the present invention is not limited thereto, and the active layer 330 may have a structure in which a semiconductor material having a large band gap energy and a semiconductor material having a small band gap energy are alternately stacked, or include different III-group to VI-group semiconductor materials according to the wavelength range of the emitted light. The active layer 330 is not limited to emitting light in the blue wavelength range, and in some cases, the active layer 330 may emit light in the red or green wavelength range. The length of the active layer 330 may be in the range of 0.05 μm to 0.25 μm, but the present invention is not limited thereto.

[0063] In addition, light emitted from the active layer 330 may be emitted to the outer surface of the light emitting element 300 in the longitudinal direction and both side surfaces of the light emitting element 300. Directivity of light emitted from the active layer 330 is not limited to one direction.

[0064] The conductive electrode layer 370 may be an ohmic contact electrode. However, the present invention is not limited thereto, and the conductive electrode layer 370 may be a Schottky contact electrode. The conductive electrode layer 370 may include a conductive metal. For example, the conductive 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 conductive electrode layer 370 may include a semiconductor material doped with n-type or p-type. The conductive electrode layer 370 may include the same material or different materials, but the present invention is not limited thereto.

[0065] The insulating film 380 is provided to surround the outer surface of the plurality of semiconductors described above. In an example, the insulating film 380 may be provided to surround at least the outer surface of the active layer 330, and may extend in one direction along which the light emitting element 300 extends. The insulating film 380 may function as a protective member. As an example, the insulating film 380 may be formed to surround the side surface of the member and expose both ends of the light emitting element 300 in the longitudinal direction.

[0066] In the drawings, the insulating film 380 is shown to be formed to extend in the longitudinal direction of the light emitting element 300 to cover from the first conductive type semiconductor 310 to the conductive electrode layer 370, but the present invention is not limited thereto. The insulating film 380 covers only the outer surfaces of some semiconductor layers including at least the active layer 330, or covers only a portion of the outer surface of the conductive electrode layer 370 so that a portion of the outer surface of the conductive electrode layer 370 may be exposed.

[0067] The thickness of the insulating film 380 may be in the range of 10 nm to 1.0 μm, but the present invention is not limited thereto. Preferably, the thickness of the insulating film 380 may be 40 nm.

[0068] According to one embodiment, in order to transmit light emitted from active layer 330 of light emitting element 300 without reflecting from insulating film 380 , insulating film 380 may include insulating coating film 381 and light conversion particles 385 disposed on at least a portion of insulating coating film 381 .

[0069] Figure 2 yes Figure 1 An enlarged view of part A of FIG. Figure 3 is a cross-sectional view showing a light emitting element according to an embodiment.

[0070] Reference Figures 1 to 3 The insulating coating film 381 is formed to surround the plurality of semiconductors. The insulating coating film 381 is provided to surround the outer surface of the light emitting element 300 including the active layer 330 .

[0071] The insulating coating film 381 may include a material having an insulating property, for example, silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon oxynitride (SiO x N y ), aluminum nitride (AlN), aluminum oxide (Al 2 O 3 ), hafnium oxide (HfO 2 ), yttrium oxide (Y 2 O 3 ), titanium dioxide (TiO 2) etc. Therefore, it is possible to prevent an electrical short circuit that may occur when the active layer 330 is in direct contact with an electrode through which an electrical signal is transmitted to the light emitting element 300, thereby preventing degradation of luminous efficiency. In addition, the insulating coating film 381 includes a transparent material, so that light emitted from the active layer 330 can pass through the insulating coating film 381.

[0072] The light conversion particles 385 are disposed on the insulating coating film 381. A plurality of light conversion particles 385 may be disposed to be spaced apart from each other, thereby forming a layer that partially covers the insulating coating film 381. The light conversion particles 385 may be completely disposed on the insulating coating film 381, but the present invention is not limited thereto, and the light conversion particles 385 may be disposed only on a partial area. In an example, the light conversion particles 385 are disposed on the insulating coating film 381, and the area in which the light conversion particles 385 are disposed may overlap at least the active layer 330. A detailed description thereof will be given below.

[0073] The light conversion particles 385 may be arranged to be attached, adsorbed or bonded to the insulating coating film 381. A physical bond or a chemical bond may be formed between the light conversion particles 385 and the insulating coating film 381, and the type of bond is not particularly limited. As an example, the light conversion particles 385 may be physically adsorbed to the insulating coating film 381. The shape of the light conversion particles 385 may be a spherical shape or an elliptical shape. However, the shape of the light conversion particles 385 is not particularly limited, and although a spherical light conversion particle 385 is shown in the drawings, the present invention is not limited thereto.

[0074] like Figure 3 As shown in FIG. 1 , in the light emitting element 300, semiconductor crystals (e.g., first conductive type semiconductor 310, second conductive type semiconductor 320, and active layer 330) may be disposed in one direction DL (hereinafter, referred to as “extension direction”) along which the light emitting element 300 extends, and an insulating coating film 381 may be formed to surround the first conductive type semiconductor 310, the second conductive type semiconductor 320, and the active layer 330. When a predetermined electrical signal is transmitted from both ends of the light emitting element 300, the active layer 330 may emit light within a specific wavelength range.

[0075] The light emitted from the active layer 330 may propagate in all directions without directivity. For example, the light emitted from the active layer 330 may include a second emission light EL2 parallel to the extension direction DL of the light emitting element 300 and a first emission light EL1 not parallel to the extension direction DL. The first emission light EL1 is emitted from the active layer 330 to propagate toward the side surface SA of the light emitting element 300, and the second emission light EL2 propagates toward both ends (e.g., the first end EA1 and the second end EA2) of the light emitting element 300 in one direction DL.

[0076] In the drawings, the first emission light EL1 is shown as including light propagating in a direction perpendicular to one direction DL and light propagating in a diagonal direction, and the present invention is not limited thereto. In the following description, it is understood that the second emission light EL2 includes light propagating toward both ends EA1 and EA2 of the light emitting element 300 in a direction substantially the same as the extension direction DL, and the first emission light EL1 is light including light propagating toward the side surface SA of the light emitting element 300 in addition to the second emission light EL2.

[0077] The light emitting element 300 may include an insulating coating film 381 surrounding at least the active layer 330, and the first emission light EL1 emitted from the active layer 330 may propagate to the insulating coating film 381 of the light emitting element 300. As described above, the insulating coating film 381 may include a transparent material, and may include an insulating material to have a predetermined refractive index. The first emission light EL1 may be incident on the insulating coating film 381, may not be emitted from the interface between the insulating coating film 381 and the outside, and may be reflected again. Therefore, a situation may occur in which the reflected first emission light EL1 propagates toward an area (e.g., the first end EA1 and the second end EA2) in which the insulating coating film 381 is not formed and is emitted in the same direction as the second emission light EL2.

[0078] As described below, the light emitting element 300 may be disposed on a target substrate, and the extension direction DL may be disposed parallel to a surface of the target substrate. That is, the light emitting element 300 may be disposed in a direction horizontal to the target substrate. The light emitted from the light emitting element 300 may be emitted from the side surface SA of the light emitting element 300 to propagate toward the upper portion of a surface of the target substrate. However, as described above, when the first emission light EL1 propagating toward the side surface SA of the light emitting element 300 is reflected from the insulating coating film 381 and emitted in the same direction as the second emission light EL2, the top emission efficiency of the horizontally disposed light emitting element 300 may be reduced.

[0079] According to one embodiment, the insulating film 380 of the light emitting element 300 may include light conversion particles 385 disposed on the insulating coating film 381, and the light conversion particles 385 may emit light (e.g., first emission light EL1) emitted from the active layer 330 to propagate toward the insulating coating film 381 to the outside of the light emitting element 300. That is, the light conversion particles 385 may provide an optical path so that light incident on the side surface SA of the light emitting element 300 is emitted as is without being reflected from the insulating coating film 381.

[0080] Figure 4 is a schematic diagram illustrating a propagation direction of light emitted from a light emitting element according to an embodiment.

[0081] Figure 5 yes Figure 4 An enlarged view of part B.

[0082] Reference Figure 2 , Figure 4 and Figure 5 In an example, the light emitting element 300 may be disposed between the electrodes 21 and 22 on the target substrate SUB. The first electrode 21 and the second electrode 22 may be disposed on the target substrate SUB. The first electrode 21 and the second electrode 22 are separated in a direction parallel to one surface of the target substrate SUB, and the light emitting element 300 is disposed so that the extension direction DL is parallel to one surface of the target substrate SUB. Both ends of the light emitting element 300 are disposed on the first electrode 21 and the second electrode 22, respectively.

[0083] However, the present invention is not limited thereto, and the arrangement structure of the light emitting element 300 may be changed. Both ends of the light emitting element 300 may be connected to at least one of the first electrode 21 and the second electrode 22, and may receive a predetermined electrical signal to emit light.

[0084] like Figure 4 and Figure 5 As shown in FIG, light emitted from the active layer 330 of the light emitting element 300 may be emitted toward both ends EA1 and EA2 of the light emitting element 300 and the insulating coating film 381 of the side surface SA. The second emission light EL2 emitted toward both ends EA1 and EA2 of the light emitting element 300 may be lost without propagating toward the upper portion of the target substrate SUB.

[0085] On the other hand, the first emission light EL1 propagating toward the side surface SA (i.e., the insulating coating film 381) of the light emitting element 300 may be emitted from the light emitting element 300, and may propagate toward the upper surface of the target substrate SUB to be displayed to the outside. When the amount of the first emission light EL1 emitted from the light emitting element 300 to the side surface SA increases, the top emission efficiency of the light emitting element 300 disposed on the target substrate SUB may be improved.

[0086] For reference Figure 5 In detail, the active layer 330 emits the second emission light EL2 in the extension direction DL of the light emitting element 300, and emits the first emission light EL1 in a direction perpendicular to the extension direction DL or in a direction inclined to the extension direction DL. The second emission light EL2 propagates in the extension direction DL to be emitted to the two ends EA1 and EA2 of the light emitting element 300.

[0087] Some of the first emission light EL1 is incident on the light conversion particles 385 through the insulating coating film 381, and the remaining first emission light EL1 is reflected from the interface between the insulating coating film 381 and the outside. The light incident on the light conversion particles 385 is emitted from the light emitting element 300 through the light conversion particles 385 ( Figure 5 EL1′ in FIG. 1 ), the light reflected from the insulating coating film 381 is emitted in the extending direction DL of the light emitting element 300 ( Figure 5 EL1 in the “EL2”).

[0088] The light emitted from the light emitting element 300 may be emitted to both end portions EA1 and EA2 in the same direction as the extending direction DL. Figure 5 EL1″ and EL2 in the extension direction DL), and can be emitted in a direction different from the extension direction DL, for example, emitted to the side surface SA in a direction perpendicular to the extension direction DL ( Figure 5 As described above, in the light emitting element 300, the extension direction DL is set in a direction parallel to the target substrate SUB, and the light emitted to the side surface SA of the light emitting element 300 can be visually identified in the direction facing the target substrate SUB. That is, when the amount of light emitted from the active layer 330 to the side surface SA of the light emitting element 300 instead of the two end portions EA1 and EA2 increases, the top emission efficiency of the target substrate SUB can be improved.

[0089] The light emitting element 300 according to one embodiment includes the light conversion particles 385 disposed on the insulating coating film 381, and thus the amount of light emitted to the side surface SA of the light emitting element 300 can be increased. Specifically, among the light incident on the insulating coating film 381, the light reflected from the interface between the insulating coating film 381 and the outside can be reduced ( Figure 5 ”) and can increase the amount of light emitted by the light conversion particles 385 ( Figure 5 The amount of light emitted to the side surface SA of the light emitting element 300 can be increased, and the top emission efficiency of the light emitting element 300 disposed on the target substrate SUB can be improved.

[0090] Meanwhile, as described above, the light conversion particles 385 providing a moving path for light emitted from the active layer 330 can scatter the incident light, change its path, or amplify its intensity. In an example, the light conversion particles 385 can be first light conversion particles 385a containing a dielectric material or second light conversion particles 385b containing precious metal particles.

[0091] Reference Figure 2 and Figure 5, the light conversion particles 385 may include first light conversion particles 385a to provide an optical path for light emitted from the active layer 330 and scatter the light at the same time. The first light conversion particles 385a may include a dielectric material to scatter light incident from the insulating coating film 381. That is, the first light conversion particles 385a may be scattering particles including a dielectric material.

[0092] As shown in the drawing, the first emission light EL1 incident on the first light conversion particle 385a may be scattered and emitted in all directions regardless of the propagation path ( Figure 5 However, in order to increase the amount of light emitted to the side surface SA of the light emitting element 300, that is, the amount of light emitted in a direction perpendicular to the extension direction DL, the first light conversion particles 385a can scatter a larger amount of light in the same direction as the propagation direction of the incident light. In other words, the first light conversion particles 385a can include a material that causes Mie scattering.

[0093] In an example, the first light conversion particles 385a may include a dielectric material having a refractive index of 1.5 or greater. For example, the first light conversion particles 385a may include silicon nitride (Si 3 N 4 ), silicon dioxide (SiO 2 ), aluminum oxide (Al 2 O 3 ), hafnium oxide (HfO 2 ), yttrium oxide (Y 2 O 3 ) and titanium dioxide (TiO 2 ). In addition, the first light conversion particle 385a may have a diameter dp1 in the range of 100 nm to 2000 nm. However, the present invention is not limited thereto.

[0094] In addition, similar to the first light conversion particles 385a, the light conversion particles 385 can scatter the incident light to control the propagation direction of the emitted light. Unlike the first light conversion particles 385a, the light conversion particles 385 can amplify the intensity of the incident light.

[0095] According to one embodiment, the light conversion particles 385 may include second light conversion particles 385 b to provide an optical path for light emitted from the active layer 330 and simultaneously amplify the intensity of the light.

[0096] Figure 6 is an enlarged view showing the outer surface of a light emitting element according to another embodiment. Figure 7 It is shown from Figure 6 Schematic diagram of the propagation of light emitted by a light-emitting element.

[0097] Reference Figure 6and Figure 7 , the light emitting element 300 includes a second light conversion particle 385b, and a plurality of the second light conversion particles 385b may be disposed on the insulating coating film 381. Similar to the first light conversion particles 385a, the second light conversion particles 385b may be physically or chemically bonded to the insulating coating film 381. For example, the second light conversion particles 385b may be adsorbed and disposed on the insulating coating film 381.

[0098] The second light conversion particles 385b can amplify the intensity of light incident through the insulating coating film 381. For example, the second light conversion particles 385b can include precious metal particles with a small particle size to generate surface plasmon resonance (SPR) with the incident light. In the precious metal particles having a diameter smaller than the wavelength of the incident light, the plasma electrons can cause a resonance phenomenon with the incident light. The intensity of the light resonating with the plasma electrons can be amplified, and the light efficiency can be improved. That is, the second light conversion particles 385b can be plasma particles.

[0099] like Figure 7 As shown in FIG. 3 , the second light conversion particles 385b disposed on the insulating coating film 381 can amplify the intensity of the first emission light EL1 incident from the active layer 330. The light ( Figure 7 The intensity of the EL1′) is amplified due to the SPR. When the light emitting element 300 includes the second light conversion particles 385b, the intensity of the light emitted from the side surface SA may be increased.

[0100] In an example, the second light conversion particles 385b may include at least one of Au, Ag, copper (Cu), and Al, and the diameter dp2 may be in the range of 10 nm to 300 nm. However, the present invention is not limited thereto.

[0101] The light emitting element 300 according to one embodiment may include at least one of the first light conversion particles 385a and the second light conversion particles 385b to increase the amount and intensity of light emitted to the side surface SA of the light emitting element 300. Therefore, the light emitting element 300 disposed parallel to the target substrate SUB in the extension direction DL is included, so that the top emission efficiency of the target substrate SUB can be improved.

[0102] In addition, the light conversion particles 385 may be disposed on at least a portion of the insulating coating film 381 to cover at least a region overlapping the active layer 330. In the light emitting element 300 according to one embodiment, the particle region PA, which is a region where the light conversion particles 385 are disposed on the insulating coating film 381, may be disposed to partially cover the insulating coating film 381 and to cover at least the active layer 330.

[0103] Refer again Figure 3, a particle area PA as a region in which the light conversion particles 385 are disposed may be defined on the insulating coating film 381 of the light emitting element 300. The light conversion particles 385 may completely cover the outer surface of the insulating coating film 381, but as shown in the drawings, the light conversion particles 385 are not disposed in some regions of the insulating coating film 381, so that the insulating coating film 381 may be exposed. In order for the first emission light EL1 emitted from the active layer 330 and propagating toward the insulating coating film 381 to be emitted through the light conversion particles 385 without being reflected, the particle area PA may be disposed adjacent to the active layer 330. In an example, the particle area PA may be disposed to overlap at least the active layer 330, and may have a shape extending in the extension direction DL of the light emitting element 300.

[0104] In addition, according to one embodiment, among the outer surface of the insulating coating film 381, the area in which the particle area PA is provided may be greater than half of the outer surface. The ratio of the particle area PA to the outer surface of the insulating coating film 381 may be in the range of 0.5 to 0.6. The particle area PA is provided to overlap at least with the active layer 330, and the area in which the particle area PA is provided may occupy 50% or more of the outer surface of the insulating coating film 381, preferably, 50% or more and 60% or less.

[0105] Meanwhile, although the particle area PA is shown as being continuously formed on the insulating coating film 381, the present invention is not limited thereto. A plurality of light conversion particles 385 may be disposed to be separated from each other on the insulating coating film 381, so that one or more particle areas PA may be defined to be separated from each other. However, the particle area PA according to one embodiment at least overlaps the active layer 330, and the sum of the areas occupied by the particle areas PA separated from each other may be 50% or more of the outer surface of the insulating coating film 381.

[0106] The method of providing the light conversion particles 385 on the insulating coating film 381 is not particularly limited. In an example, the light conversion particles 385 may be formed by immersing the semiconductor crystal on which the insulating coating film 381 is formed in a solution in which the light conversion particles 385 are dispersed or in a solution in which the precursors of the light conversion particles 385 are dissolved. For example, the light conversion particles 385 may be provided on the insulating coating film 381 by immersing the insulating coating film 381 in a sol-gel solution containing a precursor, an ink in which a precursor is dissolved, or a solution containing the light conversion particles 385. However, the present invention is not limited thereto.

[0107] Meanwhile, in some embodiments, the outer surface of the insulating coating film 381 of the insulating film 380 may be further surface-treated with other materials. When manufacturing the display device 1, the light-emitting element 300 may be injected onto the electrode in a state dispersed in a predetermined ink for arrangement. Here, in order to keep the light-emitting element 300 dispersed in the ink without agglomerating with other adjacent light-emitting elements 300, the outer surface of the insulating coating film 381 may be hydrophobic or hydrophilic.

[0108] Meanwhile, the light emitting element 300 may have a length l ranging from 1 μm to 10 μm, 4 μm to 7 μm, or 2 μm to 5 μm, and preferably, a length l of about 4 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 in the range of 1.2 to 100. However, the present invention is not limited thereto, and the plurality of light emitting elements 300 included in the display device 1 may have different diameters according to the difference in the composition of the active layer 330. Preferably, the diameter of the light emitting element 300 may be about 500 nm.

[0109] As described above, the light emitting element 300 includes the light conversion particles 385 disposed on the insulating coating film 381. The light emitting element 300 has a shape extending in one direction, and the light emitted from the light emitting element 300 may propagate in a direction parallel to the extension direction DL and in a direction different from the extension direction DL. Here, the light emitted from the active layer 330 is incident on the light conversion particles 385 disposed on the insulating coating film 381, and the light conversion particles 385 may emit the light to the side surface SA of the light emitting element 300 or amplify the intensity of the light. In the light emitting element 300 according to one embodiment, the amount of light emitted in a direction different from or perpendicular to the extension direction DL may be increased.

[0110] In the light emitting element 300 according to one embodiment, the amount of light emitted to the side surface SA increases, so that even when the light emitting element 300 is arranged in a direction parallel to the target substrate SUB, the top emission efficiency can be high. Figure 4 Differently, the arrangement structure of the light emitting element 300 between the electrodes 21 and 22 on the target substrate SUB may be changed.

[0111] Figures 8 to 10 FIG. 1 is a schematic diagram showing that a light emitting element is disposed on a substrate according to an embodiment.

[0112] The light emitting element 300 may be disposed on the target substrate SUB such that the extension direction DL is parallel to the target substrate SUB. Figure 4Different from the above, the light emitting element 300 may not be disposed on the electrodes 21 and 22, but may be disposed between the electrodes 21 and 22. Figure 4 difference.

[0113] Reference Figure 8 According to one embodiment, the light emitting element 300 is disposed between the first electrode 21 and the second electrode 22, so that the first end EA1 of the light emitting element 300 can contact the side surface of the first electrode 21, and the second end EA2 of the light emitting element 300 can contact the side surface of the second electrode 22. The distance between the first electrode 21 and the second electrode 22 can be the same as the length l of the light emitting element 300 measured in the extension direction DL. Figure 4 In the embodiment, the side surfaces of both ends of the light emitting element 300 are in contact with the upper surfaces of the first electrode 21 and the second electrode 22, but in Figure 8 There is a difference in which the first end portion EA1 and the second end portion EA2 are in contact with the side surfaces of the first electrode 21 and the second electrode 22 .

[0114] As described above, since the light emitting element 300 includes the light conversion particles 385, the amount of light emitted to the side surface SA can be greater than the amount of light emitted in the extension direction DL. That is, the light emitting element 300 disposed between the first electrode 21 and the second electrode 22 can emit light to the side surface SA, so that the light can propagate toward the upper portion of the target substrate SUB. Even when the two end portions EA1 and EA2 of the light emitting element 300 are in contact with the electrodes 21 and 22, respectively, and the emission of light is blocked or hindered, the light emitting element 300 can emit a sufficient amount of light to the upper portion of the target substrate SUB through the side surface SA.

[0115] Alternatively, the light emitting element 300 may be provided as a plurality of light emitting elements 300 between the first electrode 21 and the second electrode 22. Each light emitting element 300 may emit a sufficient amount of light toward the side surface SA, and the plurality of light emitting elements 300 may be provided between the first electrode 21 and the second electrode 22 in a direction perpendicular to one surface of the target substrate SUB.

[0116] Reference Fig. 9 According to one embodiment, the light emitting element 300 includes a first light emitting element 301 and a second light emitting element 302, and the first light emitting element 301 and the second light emitting element 302 may have different separation distances from one surface of the target substrate SUB. Fig. 9 As shown in FIG. 1 , both end portions EA1 and EA2 of the first light emitting element 301 and the second light emitting element 302 may be in contact with the side surfaces of the first electrode 21 and the second electrode 22, respectively. Figure 8 Different, exist Fig. 9The light emitting element 300 is disposed between the first electrode 21 and the second electrode 22 to have a difference in separation from the target substrate SUB. In addition, the first light emitting element 301 and the second light emitting element 302 may have different separation distances from the target substrate SUB.

[0117] The first light emitting element 301 and the second light emitting element 302 are arranged in a direction perpendicular to one surface of the target substrate SUB, for example, to be separated from the upper surface of the target substrate SUB. The distance h1 between the first light emitting element 301 and the target substrate SUB may be smaller than the distance h2 between the second light emitting element 302 and the target substrate SUB. That is, in the drawings, the first light emitting element 301 may be located below the second light emitting element 302.

[0118] A large number of light emitting elements 300 are disposed in a narrow region between the first electrode 21 and the second electrode 22, so that the amount of light emitted from the side surface SA of the light emitting element 300 can be further increased. That is, the first light emitting element 301 and the second light emitting element 302 constituting a plurality of layers are disposed between the electrodes 21 and 22, so that the amount of light emitted per unit area of ​​the target substrate SUB can be increased.

[0119] Meanwhile, according to one embodiment, the light emitting element 300 may be disposed between the first electrode 21 and the second electrode 22 , the first electrode 21 and the second electrode 22 being separated by the light emitting element 300 , and the contact electrode 26 may be further disposed between the light emitting element 300 and the first electrode 21 and the second electrode 22 .

[0120] Reference Fig.10 , the light emitting element 300 may be disposed between the first electrode 21 and the second electrode 22, and both end portions EA1 and EA2 may be disposed to be separated from the electrodes 21 and 22, respectively. The contact electrode 26 is further disposed to contact the light emitting element 300 and the electrodes 21 and 22 in a region where the light emitting element 300 and the electrodes 21 and 22 are separated from each other.

[0121] Specifically, the contact electrode 26 includes a first contact electrode 26a in contact with the first end EA1 of the light emitting element 300 and the first electrode 21 and a second contact electrode 26b in contact with the second end EA2 of the light emitting element 300 and the second electrode 22. Figure 8 and Fig. 9 Different, in Fig.10, the light emitting element 300 may not be in direct contact with the electrodes 21 and 22, but may be connected to the electrodes 21 and 22 through the contact electrode 26. Although not shown in the drawings, when the length of the light emitting element 300 measured in the extension direction DL is equal to the distance between the electrodes 21 and 22, at least one end of the light emitting element 300 may not be connected to the electrode 21 or 22. In order to prevent this, the distance between the first electrode 21 and the second electrode 22 may be greater than the length l of the light emitting element 300, and the light emitting element 300 may be connected to the electrodes 21 and 22 through the contact electrode 26.

[0122] In addition, in the example, each of the electrodes 21 and 22 may include a material having a high reflectivity. As shown in the drawings, the second emission light EL2 may be emitted from both ends EA1 and EA2 of the light emitting element 300 to propagate toward the electrodes 21 and 22. When each of the electrodes 21 and 22 includes a material having a high reflectivity, the second emission light EL2 emitted in the extension direction DL of the light emitting element 300 may be reflected in an upward direction from the target substrate SUB. Therefore, the top emission efficiency of the light emitting element 300 disposed on the target substrate SUB may be further improved.

[0123] The light emitting element 300 may emit light within a specific wavelength range, for example, blue light, and the display device 1 according to one embodiment may include at least one light emitting element 300 to display light of a specific color.

[0124] Fig.11 is a plan view showing a display device including a light emitting element manufactured by a method according to an embodiment.

[0125] Reference Fig.11 , the display device 1 may include a plurality of pixels PX. Each of the pixels PX may include one or more light emitting elements 300 that emit light within a specific wavelength range to display a specific color.

[0126] Each of the plurality of pixels PX may include a first sub-pixel PX1, a second sub-pixel PX2, and a third sub-pixel PX3. The first sub-pixel PX1 may emit light of a first color, the second sub-pixel PX2 may emit light of a second color, and the third sub-pixel PX3 may emit light of a third color. The first color may be red, the second color may be green, and the third color may be blue, but the present invention is not limited thereto, and each sub-pixel PXn (e.g., PX1, PX2, or PX3) may emit light of the same color. In addition, although each pixel PX Fig.11 1 and 2 are shown as including three sub-pixels, but the present invention is not limited thereto, and each pixel PX may include a greater number of sub-pixels.

[0127] Each sub-pixel PXn of the display device 1 may include an area defined as an emission area and a non-emission area. The emission area is defined as an area in which the light emitting element 300 included in the display device 1 is disposed to emit light within a specific wavelength range. The non-emission area is an area other than the emission area, and may be defined as an area in which the light emitting element 300 is not disposed and light is not emitted therefrom.

[0128] The sub-pixel PXn of the display device 1 may include a plurality of banks 40 , a plurality of electrodes 21 and 22 , and a light emitting element 300 .

[0129] The plurality of electrodes 21 and 22 may be electrically connected to the light emitting element 300 and may receive a predetermined voltage to cause the light emitting element 300 to emit light. In addition, at least a portion of each of the electrodes 21 and 22 may be used to form an electric field in the subpixel PXn to align the light emitting element 300.

[0130] Specifically, the plurality of electrodes 21 and 22 may include a first electrode 21 and a second electrode 22. In an example, the first electrode 21 may be a pixel electrode separated for each sub-pixel PXn, and the second electrode 22 may be a common electrode commonly connected along each sub-pixel PXn. One of the first electrode 21 and the second electrode 22 may be an anode electrode of the light emitting element 300, and the other may be a cathode electrode of the light emitting element 300. However, the present invention is not limited thereto, and the opposite of the above may be possible.

[0131] The first and second electrodes 21 and 22 may include electrode trunk portions 21S and 22S disposed to extend in a first direction D1 , and electrode branch portions 21B and 22B branched and extended from the electrode trunk portions 21S and 22S, respectively, in a second direction D2 crossing the first direction D1 .

[0132] The first electrode 21 may include a first electrode trunk portion 21S disposed to extend in the first direction D1 and at least one first electrode branch portion 21B branched from the first electrode trunk portion 21S to extend in the second direction D2 .

[0133] Both ends of the first electrode trunk 21S of any one pixel may be separated to terminate between sub-pixels PXn, and disposed substantially collinearly with the first electrode trunk 21S of adjacent sub-pixels PXn in the same row (e.g., adjacent in the first direction D1). Therefore, the first electrode trunk 21S disposed in the corresponding sub-pixel PXn may apply different electrical signals to the corresponding first electrode branch portions 21B, and the first electrode branch portions 21B may each be driven separately.

[0134] The first electrode branch portion 21B branches from at least a portion of the first electrode trunk portion 21S and is disposed to extend in the second direction D2. The first electrode branch portion 21B may terminate in a state separated from the second electrode trunk portion 22S disposed opposite to the first electrode trunk portion 21S.

[0135] The second electrode 22 may include a second electrode trunk 22S and a second electrode branch 22B, the second electrode trunk 22S extending in the first direction D1 and arranged to be separated from and opposite to the first electrode trunk 21S, and the second electrode branch 22B branching from the second electrode trunk 22S and arranged to extend in the second direction D2. However, both ends of the second electrode trunk 22S may extend to a plurality of adjacent sub-pixels PXn in the first direction D1. Therefore, both ends of the second electrode trunk 22S of any pixel may be connected to the second electrode trunk 22S of an adjacent pixel PX between pixels PX.

[0136] The second electrode branch portion 22B may be separated from and opposite to the first electrode branch portion 21B, and terminate in a state of being separated from the first electrode trunk portion 21S. That is, one end of the second electrode branch portion 22B may be connected to the second electrode trunk portion 22S, and the other end of the second electrode branch portion 22B may be disposed in the subpixel PXn in a state of being separated from the first electrode trunk portion 21S.

[0137] In the drawings, it is shown that two first electrode branch portions 21B are provided, and the second electrode branch portion 22B is shown to be provided between the two first electrode branch portions 21B, but the present invention is not limited thereto.

[0138] A plurality of dikes 40 (see Fig.12 ) may include a third bank 43 disposed at a boundary between sub-pixels PXn and first and second banks 41 and 42 disposed respectively under the electrodes 21 and 22. Although the first and second banks 41 and 42 are not shown in the drawings, the first and second banks 41 and 42 may be disposed respectively under the first and second electrode branch portions 21B and 22B.

[0139] The third bank 43 may be disposed at a boundary between sub-pixels PXn. Ends of the plurality of first electrode trunks 21S may be separated from each other based on the third bank 43 to terminate. The third bank 43 may extend along the second direction D2 and may be disposed at a boundary between sub-pixels PXn disposed along the first direction D1. However, the present invention is not limited thereto, and the third bank 43 may extend in the first direction D1 and may be disposed at a boundary between sub-pixels PXn disposed along the second direction D2. The third bank 43 may include the same material as the first bank 41 and the second bank 42, and may be formed in substantially the same process.

[0140] Although not shown in the drawings, the first insulating layer 51 may be provided in each sub-pixel PXn to completely cover each sub-pixel PXn including the first electrode branch portion 21B and the second electrode branch portion 22B. The first insulating layer 51 may protect each of the electrodes 21 and 22 and simultaneously insulate the electrodes 21 and 22 from each other so as not to directly contact each other.

[0141] A plurality of light emitting elements 300 may be disposed between the first electrode branch 21B and the second electrode branch 22B. One end of at least some of the plurality of light emitting elements 300 may be electrically connected to the first electrode branch 21B, and the other end of at least some of the light emitting elements 300 may be electrically connected to the second electrode branch 22B.

[0142] The plurality of light emitting elements 300 may be separated from each other in the second direction D2 and arranged substantially parallel to each other. The separation distance between the light emitting elements 300 is not particularly limited. In some cases, the plurality of light emitting elements 300 may be arranged adjacent to each other to form a group, and another plurality of light emitting elements 300 may be grouped in a state separated by a certain interval, may have a non-uniform density, and may be oriented in one direction to be arranged.

[0143] As described above, the light emitting element 300 may include the light conversion particles 385 disposed on the insulating coating film 381 and emit light toward the upper portion of the display device 1. That is, the display device 1 may include Figure 1 The light emitting element 300 can thus improve the top emission efficiency.

[0144] The contact electrode 26 may be disposed on the first electrode branch 21B and the second electrode branch 22B. However, the contact electrode 26 may be substantially disposed on the first insulating layer 51, and at least a portion of the contact electrode 26 may be in contact with or electrically connected to the first electrode branch 21B and the second electrode branch 22B.

[0145] A plurality of contact electrodes 26 may be provided to extend in the second direction D2 and to be separated from each other in the first direction D1. The contact electrode 26 may contact at least one end of the light emitting element 300, and the contact electrode 26 may contact the first electrode 21 or the second electrode 22 to receive an electrical signal. Therefore, the contact electrode 26 may transmit an electrical signal transmitted from each of the electrodes 21 and 22 to the light emitting element 300.

[0146] The contact electrode 26 may include a first contact electrode 26a and a second contact electrode 26b. The first contact electrode 26a may be disposed on the first electrode branch 21B to contact one end of the light emitting element 300, and the second contact electrode 26b may be disposed on the second electrode branch 22B to contact the other end of the light emitting element 300.

[0147] The first electrode trunk 21S and the second electrode trunk 22S may be electrically connected to the circuit element layer of the display device 1 through corresponding contact holes (e.g., the first electrode contact hole CNTD and the second electrode contact hole CNTS). In the drawings, one second electrode contact hole CNTS is shown as being formed in the second electrode trunk 22S of a plurality of sub-pixels PXn. However, the present invention is not limited thereto, and in some cases, the second electrode contact hole CNTS may be formed in each sub-pixel PXn.

[0148] In addition, although not shown in the drawings, the display device 1 may include a second insulating layer 52 (see FIG. 5 ) disposed to cover at least a portion of each of the electrodes 21 and 22 and the light emitting element 300. Fig.12 ) and passivation layer 55 (see Fig.12 ). The following will refer to Fig.12 Describe the arrangement and structure between the above components.

[0149] Fig.12 is along Fig.11 A partial cross-sectional view taken along line II-II'.

[0150] Fig.12 A cross-sectional view of the first subpixel PX1 is shown, and may be similarly applied to another pixel PX or another subpixel PXn. Fig.12 A cross section across one end and the other end of any light emitting element 300 is shown.

[0151] In addition, despite the Fig.12 Although not shown in the figure, the display device 1 may further include a circuit element layer located below the electrodes 21 and 22. The circuit element layer may include a plurality of semiconductor layers and a plurality of conductive patterns, and may include at least one transistor and a power supply line. However, a detailed description thereof will be omitted below.

[0152] Reference Fig.12 , the display device 1 may include a via layer 20, electrodes 21 and 22 disposed on the via layer 20, and a light emitting element 300. A circuit element layer (not shown) may be further disposed under the via layer 20. The via layer 20 may include an organic insulating material and perform a surface planarization function.

[0153] A plurality of banks 41, 42, and 43 are disposed on the via layer 20. The plurality of banks 41, 42, and 43 may be disposed to be separated from each other in each sub-pixel PXn. The plurality of banks 41, 42, and 43 may include a first bank 41 and a second bank 42 disposed adjacent to a central portion of the sub-pixel PXn, and a third bank 43 disposed at a boundary between the sub-pixels PXn.

[0154] When the ink (I) is ejected using an inkjet printing device during the manufacture of the display device 1, the third bank 43 may perform a function of blocking the ink (I) from crossing the boundary of the sub-pixel PXn. In addition, when the display device 1 further includes another member, the other member may be disposed on the third bank 43, and the third bank 43 may perform a function of supporting the other member. However, the present invention is not limited thereto.

[0155] The first bank 41 and the second bank 42 are disposed to be separated from each other and to face each other. The first electrode 21 may be disposed on the first bank 41, and the second electrode 22 may be disposed on the second bank 42. Fig.11 and Fig.12 It can be understood that the first electrode branch portion 21B is disposed on the first bank 41 , and the second electrode branch portion 22B is disposed on the second bank 42 .

[0156] As described above, the first bank 41, the second bank 42, and the third bank 43 may be formed in substantially the same process. Therefore, the banks 41, 42, and 43 may constitute a single grid pattern. Each of the plurality of banks 41, 42, and 43 may include polyimide (PI).

[0157] Each of the plurality of banks 41, 42, and 43 may have a structure in which at least a portion protrudes from the via layer 20. The banks 41, 42, and 43 may protrude upward based on a plane on which the light emitting element 300 is disposed, and at least a portion of each protrusion may have a slope. The shape of each of the banks 41, 42, and 43 having a protruding structure is not particularly limited. As shown in the drawings, the first bank 41 and the second bank 42 protrude to the same height, and the third bank 43 may have a shape that protrudes to a higher position.

[0158] Reflective layers 21a and 22a may be disposed on the first and second banks 41 and 42, and electrode layers 21b and 22b may be disposed on the reflective layers 21a and 22a. The reflective layers 21a and 22a and the electrode layers 21b and 22b may constitute electrodes 21 and 22, respectively.

[0159] The reflective layers 21a and 22a include a first reflective layer 21a and a second reflective layer 22a. The first reflective layer 21a may cover the first bank 41, and the second reflective layer 22a may cover the second bank 42. A portion of the reflective layers 21a and 22a is electrically connected to the circuit element layer through a contact hole passing through the via layer 20.

[0160] Each of the reflective layers 21a and 22a may include a material having high reflectivity to reflect light emitted from the light emitting element 300. For example, each of the reflective layers 21a and 22a may include a material such as Ag, Cu, ITO, IZO, or ITZO, but the present invention is not limited thereto.

[0161] The electrode layers 21b and 22b include a first electrode layer 21b and a second electrode layer 22b. The electrode layers 21b and 22b may have substantially the same pattern as that of the reflective layers 21a and 22a. The first reflective layer 21a and the first electrode layer 21b are disposed to be separated from the second reflective layer 22a and the second electrode layer 22b.

[0162] Each of the electrode layers 21b and 22b includes a transparent conductive material, so that the emission light emitted from the light emitting element 300 can be incident on the reflective layers 21a and 22a. For example, each of the electrode layers 21b and 22b may include a material such as ITO, IZO, or ITZO, but the present invention is not limited thereto.

[0163] In some embodiments, the reflective layers 21a and 22a and the electrode layers 21b and 22b may form a structure in which one or more transparent conductive layers (such as ITO, IZO or ITZO) and one or more metal layers (such as Ag or Cu) are stacked. For example, the reflective layers 21a and 22a and the electrode layers 21b and 22b may form a stacked structure of ITO / Ag / ITO / IZO.

[0164] In addition, in some embodiments, the first electrode 21 and the second electrode 22 may be formed as a single layer. That is, the reflective layers 21a and 22a and the electrode layers 21b and 22b may be formed as a single layer to transmit an electrical signal to the light emitting element 300 while reflecting light. For example, each of the first electrode 21 and the second electrode 22 may include a conductive material having a high reflectivity, and may be an alloy containing Al, nickel (Ni) and lanthanum (La). However, the present invention is not limited thereto.

[0165] The first insulating layer 51 is disposed to partially cover the first electrode 21 and the second electrode 22. The first insulating layer 51 may be disposed to cover most of the upper surfaces of the first electrode 21 and the second electrode 22, and may expose portions of the first electrode 21 and the second electrode 22. The first insulating layer 51 may be disposed to partially cover a region where the first electrode 21 is separated from the second electrode 22 and a region opposite to the region where the first electrode 21 is separated from the second electrode 22.

[0166] The first insulating layer 51 is provided to expose the relatively flat upper surfaces of the first electrode 21 and the second electrode 22, and is provided so that the electrodes 21 and 22 overlap the inclined surfaces of the first bank 41 and the second bank 42. The first insulating layer 51 forms a flat upper surface to allow the light emitting element 300 to be provided, and the flat upper surface extends in one direction toward the first electrode 21 and the second electrode 22. The extended portion of the first insulating layer 51 ends at the inclined surfaces of the first electrode 21 and the second electrode 22. Therefore, the contact electrode 26 can contact the exposed first electrode 21 and the exposed second electrode 22, and can smoothly contact the light emitting element 300 on the flat upper surface of the first insulating layer 51.

[0167] The first insulating layer 51 may protect the first electrode 21 and the second electrode 22, and simultaneously insulate the first electrode 21 from the second electrode 22. In addition, the first insulating layer 51 may prevent the light emitting element 300 disposed thereon from being damaged due to direct contact with other members.

[0168] The light emitting element 300 may be disposed on the first insulating layer 51. At least one light emitting element 300 may be disposed on the first insulating layer 51 between the first electrode 21 and the second electrode 22. The light emitting element 300 may include a plurality of layers disposed in a horizontal direction with respect to the via layer 20.

[0169] The light emitting element 300 of the display device 1 according to one embodiment may include the conductive semiconductor and the active layer as described above, and the conductive semiconductor and the active layer may be sequentially arranged on the via layer 20 in the horizontal direction. As shown in the drawings, in the light emitting element 300, the first conductive semiconductor 310, the active layer 330, the second conductive semiconductor 320 and the conductive electrode layer 370 may be sequentially arranged on the via layer 20 in the horizontal direction. However, the present invention is not limited thereto. The order of the multiple layers arranged in the light emitting element 300 may be reversed. In some cases, when the light emitting element 300 has another structure, the multiple layers may be arranged in a direction perpendicular to the via layer 20.

[0170] The second insulating layer 52 may be partially disposed on the light emitting element 300. The second insulating layer 52 may protect the light emitting element 300 and simultaneously perform a function of fixing the light emitting element 300 during a process of manufacturing the display device 1. The second insulating layer 52 may be disposed to surround the outer surface of the light emitting element 300. That is, a portion of the material of the second insulating layer 52 may be disposed between the bottom surface of the light emitting element 300 and the first insulating layer 51. When viewed in a plan view, the second insulating layer 52 may extend between the first electrode branch portion 21B and the second electrode branch portion 22B along the second direction D2 to have an island shape or a linear shape.

[0171] The contact electrode 26 is disposed on the electrodes 21 and 22 and the second insulating layer 52. The first contact electrode 26a and the second contact electrode 26b are disposed to be separated from each other on the second insulating layer 52. Therefore, the second insulating layer 52 may insulate the first contact electrode 26a from the second contact electrode 26b.

[0172] The first contact electrode 26a may be in contact with at least one end of the first electrode 21 and the light emitting element 300 exposed due to the patterning of the first insulating layer 51. The second contact electrode 26b may be in contact with at least the second electrode 22 and the other end of the light emitting element 300 exposed due to the patterning of the first insulating layer 51. The first contact electrode 26a and the second contact electrode 26b may be in contact with the side surfaces of both ends of the light emitting element 300 (for example, the first conductive semiconductor 310, the second conductive semiconductor 320, or the conductive electrode layer 370). As described above, the first insulating layer 51 forms a flat upper surface so that the contact electrode 26 can smoothly contact the side surface of the light emitting element 300.

[0173] The contact electrode 26 may include a conductive material. For example, the contact electrode 26 may include ITO, IZO, ITZO, Al, etc. However, the present invention is not limited thereto.

[0174] The passivation layer 55 may be formed on the second insulating layer 52 and the contact electrode 26 , and may serve to perform a function of protecting members disposed on the via layer 20 from an external environment.

[0175] Each of the first insulating layer 51, the second insulating layer 52, and the passivation layer 55 described above may include an inorganic insulating material or an organic insulating material. In an example, each of the first insulating layer 51 and the passivation layer 55 may include a SiO x 、SiN x 、SiO x N y 、Al 2 O 3 , aluminum nitride (AlN), etc. The second insulating layer 52 may be made of an organic insulating material including a photoresist, etc. However, the present invention is not limited thereto.

[0176] As described above, the display device 1 includes a plurality of banks 40, specifically, the first bank 41 and the second bank 42, and the electrodes 21 and 22 may be provided on the inclined surfaces of the banks 41 and 42. Among the light emitted from the light emitting element 300, the second emission light EL2 emitted in the extension direction DL of the light emitting element 300 may propagate toward the electrodes 21 and 22 formed on the inclined surfaces of the banks 41 and 42. The electrodes 21 and 22 including the reflective layers 21a and 22a may reflect the incident second emission light EL2 toward the upper portion of the light emitting element 300, and the top emission efficiency of the display device 1 may be improved.

[0177] However, the light emitting element 300 according to one embodiment may include light conversion particles 385 disposed on the insulating coating film 381 to emit the first emission light EL1 in a direction perpendicular to the extension direction DL of the light emitting element 300. When the display device 1 includes Figure 1 When the light emitting element 300 is not reflected by the inclined banks 41 and 42 to the upper portion of the light emitting element 300, the display device 1 can emit a sufficient amount of emission light toward the upper portion of the light emitting element 300 through the light conversion particles 385. That is, in the display device 1 according to another embodiment, the banks (specifically, the first bank 41 and the second bank 42) can be omitted.

[0178] Fig.13 is a cross-sectional view showing a display device according to another embodiment.

[0179] Reference Fig.13 , in the display device 1, the first bank 41 and the second bank 42 may be omitted, and the first electrode 21 and the second electrode 22 may be directly disposed on the via layer 20. Fig.13 Not shown, but Fig.12 As shown in , the light conversion particles 385 may be disposed on the insulating coating film 381 of the outer surface of the light emitting element 300 , and the light emitted from the active layer 330 of the light emitting element 300 may propagate toward the upper portion based on the via layer 20 .

[0180] Therefore, with Fig.12 Unlike the display device 1 of FIG. 1 , there is an advantage in that the operation of forming the banks 41 and 42 is omitted, and the steps between the components provided on the via layer 20 can be reduced. In addition, since the top emission efficiency can be sufficiently obtained even when the light emitted from the light emitting element 300 is not reflected, the reflective layers 21a and 22a can be omitted from the electrodes 21 and 22. The description of the other components is the same as that of the above reference Fig.12 Those described are the same and thus will be omitted here.

[0181] Meanwhile, the display device 1 may further include Figure 1The structure of the light emitting element 300 is different from the structure of the light emitting element 300.

[0182] Fig.14 is a schematic diagram of a light emitting element according to another embodiment.

[0183] Reference Fig.14 , the light emitting element 300' may be formed such that a plurality of layers are not stacked in one direction, and each of the plurality of layers surrounds an outer surface of another layer. In addition to the shapes of the layers being partially different from each other, Fig.14 The light emitting element 300' and Figure 1 The light emitting element 300 is the same as that of FIG. 8 . Hereinafter, the same contents will be omitted and the differences will be described.

[0184] According to one embodiment, the first conductive type semiconductor 310 ′ may extend in one direction, and both end portions thereof may be formed to be inclined toward a central portion thereof. Fig.13 The first conductive type semiconductor 310' may have a shape in which a rod-shaped or cylindrical body and conical ends on the upper and lower parts of the body are formed. The upper end of the body may have a slope steeper than that of the lower end thereof.

[0185] The active layer 330' is provided to surround the outer surface of the body of the first conductive type semiconductor 310'. The active layer 330' may have a ring shape extending in one direction. The active layer 330' may not be formed on the upper end and the lower end of the first conductive type semiconductor 310'. That is, the active layer 330' may only contact the parallel side surfaces of the first conductive type semiconductor 310'.

[0186] The second conductive semiconductor 320' is disposed to surround the outer surface of the active layer 330' and the upper end of the first conductive semiconductor 310'. The second conductive semiconductor 320' may include a ring-shaped body extending in one direction and an upper end having a side surface formed to be inclined. That is, the second conductive semiconductor 320' may be in direct contact with the parallel side surfaces of the active layer 330' and the inclined upper end of the first conductive semiconductor 310'. However, the second conductive semiconductor 320' is not formed in the lower end of the first conductive semiconductor 310'.

[0187] The electrode material layer 370' is disposed to surround the outer surface of the second conductive semiconductor 320'. That is, the shape of the electrode material layer 370' may be substantially the same as the shape of the second conductive semiconductor 320'. That is, the electrode material layer 370' may completely contact the outer surface of the second conductive semiconductor 320'.

[0188] The insulating film 380' may be disposed to surround the outer surface of the electrode material layer 370' and the first conductive type semiconductor 310'. In addition to the electrode material layer 370', the insulating film 380' may also be in direct contact with the lower end of the first conductive type semiconductor 310' and the exposed lower ends of the active layer 330' and the second conductive type semiconductor 320'. Fig.14 As shown in , the light emitting element 300 ′ may have a length l ′ extending in one direction.

[0189] Even in Fig.14 In the light emitting element 300', the insulating film 380' also includes the insulating coating film and the light conversion particles 385', so the light emitting element 300' can emit a sufficient amount of light in a direction perpendicular to the direction along which the light emitting element 300' extends. The detailed description thereof is the same as the above description, and thus will be omitted here.

[0190] In summarizing the detailed description, it will be appreciated by those skilled in the art that many changes and modifications may be made to the preferred embodiments without departing substantially from the principles of the present invention. Therefore, the preferred embodiments of the disclosed invention are used in a general and descriptive sense only, and not for the purpose of limitation.

Claims

1. A light-emitting element, comprising: A first conductivity type semiconductor, doped with a first polarity; A second conductivity type semiconductor, doped with a second polarity opposite to the first polarity; an active layer, disposed between the first conductive type semiconductor and the second conductive type semiconductor; as well as an insulating film, the insulating film surrounding at least a side surface of the active layer, wherein the first conductive type semiconductor, the active layer, and the second conductive type semiconductor are sequentially stacked in a first direction which is an extending direction of the light emitting element, and the active layer emits light, wherein the insulating film includes an insulating coating film and at least one light conversion particle disposed on at least a portion of the insulating coating film, and the at least one light conversion particle includes a first light conversion particle that scatters incident light emitted from the active layer, wherein the first light conversion particles are configured to increase the proportion of light emitted in a direction perpendicular to the first direction, wherein, in the light emitting element, the amount of light emitted in the direction perpendicular to the first direction is greater than the amount of light emitted in the first direction, and The light emitting element has a shape of a nanorod, a nanowire or a nanotube extending in the first direction.

2. The light-emitting element according to claim 1, wherein The light emitted from the active layer includes first emission light propagating in the first direction toward both ends of the light emitting element and second emission light propagating in a second direction different from the first direction.

3. The light-emitting element according to claim 2, wherein At least a portion of the second emitted light is incident on the at least one light conversion particle and is emitted from the active layer in the direction perpendicular to the first direction.

4. The light-emitting element according to claim 1, wherein The at least one light conversion particle further includes second light conversion particles that amplify the intensity of the incident light.

5. The light emitting element according to claim 4, wherein The first light conversion particles include at least one of silicon nitride, silicon dioxide, aluminum oxide, hafnium oxide, yttrium oxide, and titanium dioxide.

6. The light-emitting element according to claim 5, wherein The diameter of the first light conversion particles is in the range of 100 nm to 2000 nm.

7. The light emitting element according to claim 4, wherein The second light conversion particles include at least one of gold, silver, copper and aluminum.

8. The light-emitting element according to claim 7, wherein The diameter of the second light conversion particles is in the range of 10 nm to 300 nm.

9. The light emitting element according to claim 1, further comprising a particle region, the particle region being defined as a region in which the at least one light conversion particle is disposed on the insulating coating film, in, The particle region is provided on the insulating coating film to overlap at least the active layer.

10. The light emitting element according to claim 9, wherein The particle region has a shape extending in the first direction.

11. The light emitting element according to claim 10, wherein A ratio of an area of ​​the particle region to an area of ​​an outer surface of the insulating coating film is in a range of 0.5 to 0.

6.

12. The light emitting element according to claim 9, wherein The light emitting element has a length in the range of 4 μm to 7 μm and an aspect ratio in the range of 1.2 to 100.

13. A display device, comprising: Base layer; a first electrode and a second electrode, the first electrode and the second electrode being separated from each other along a first direction on the base layer; as well as at least one light emitting element disposed between the first electrode and the second electrode, wherein the at least one light emitting element includes a semiconductor crystal and an insulating film, the semiconductor crystal having a shape extending in the first direction and configured to emit light within a specific wavelength range, and the insulating film being configured to surround a side surface of the semiconductor crystal, The semiconductor crystal includes a first conductive type semiconductor, an active layer, and a second conductive type semiconductor sequentially stacked in the first direction, The insulating film includes an insulating coating film and at least one light conversion particle disposed on at least a portion of the insulating coating film, and the at least one light conversion particle includes a first light conversion particle that scatters incident light emitted from the semiconductor crystal, The first light conversion particles are configured to increase the proportion of light emitted in a direction perpendicular to the first direction, In the at least one light emitting element, an amount of light emitted in the direction perpendicular to the first direction is greater than an amount of light emitted in the first direction, and The at least one light emitting element has a shape of a nanorod, a nanowire or a nanotube extending in the first direction.

14. The display device according to claim 13, wherein: At least some of the light emitted from the semiconductor crystal is incident on the at least one light converting particle and is emitted in a direction different from the first direction.

15. The display device according to claim 13, wherein: The at least one light conversion particle further includes second light conversion particles that amplify the intensity of the incident light.

16. The display device according to claim 14, wherein: The at least one light emitting element comprises a first light emitting element and a second light emitting element; and The first light emitting element and the second light emitting element have different separation distances from the base layer in a second direction perpendicular to the base layer.

17. The display device according to claim 14, further comprising: a first contact electrode in contact with the first electrode and one end of the at least one light emitting element; as well as The second contact electrode is in contact with the second electrode and the other end of the at least one light emitting element.

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