Light-emitting devices

Abstract

A light emitting device (LED) is disclosed, comprising: a first semiconductor layer; a second semiconductor layer facing the first semiconductor layer; an insulating layer arranged to at least partially surround the outer surfaces of the first semiconductor layer and the second semiconductor layer; and a first ligand and a second ligand, the first ligand being bound to the surface of the insulating layer and the second ligand being bound to the first ligand.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2020-0003880 filed on January 10, 2020, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0002] One or more embodiments of the present disclosure are directed to a light emitting device and a display apparatus including the same. Background Art

[0003] Light emitting devices (LEDs) have high light conversion efficiency and very low energy consumption, and are semi-permanent and environmentally friendly. In order to use LEDs for lighting devices or display devices, the LEDs are combined between a pair of electrodes that can apply power to the LEDs. The methods of combining LEDs to electrodes can be classified into methods such as growing LEDs directly on a pair of electrodes and growing LEDs separately and aligning the LEDs on the electrodes. In the latter case, when the LEDs are nano-scale or micro-scale, it is difficult to align the LEDs on the electrodes. Summary of the invention

[0004] One or more embodiments include a display device in which a first ligand is bonded to a surface of an independently manufactured nanoscale or microscale light emitting device (LED), and a second ligand is bonded to the first ligand, thereby improving the dispersibility of the LED in the ink composition and improving the ratio of the LED alignment between a pair of electrodes. However, this feature is only an example, and the scope of the disclosure is not limited thereto.

[0005] Additional aspects of the embodiments will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented disclosed embodiments.

[0006] According to one or more embodiments, a light emitting device (LED) includes: a first semiconductor layer; a second semiconductor layer facing the first semiconductor layer; an insulating layer arranged to at least partially surround an outer surface of the first semiconductor layer and an outer surface of the second semiconductor layer; and a first ligand and a second ligand, the first ligand being bound to a surface of the insulating layer and the second ligand being bound to the first ligand.

[0007] The first ligand may be derived from a compound represented by formula 1:

[0008] Formula 1

[0009] A 1 -R 1 -A 2

[0010] Among them, in formula 1,

[0011] A 1 is selected from alkylsiloxane groups, alkylphosphonic acid groups, catechol groups, alkylcatechol groups, carboxylic acid groups, thiol groups and amine groups,

[0012] A 2 is selected from a halogen group, a vinyl group, an acetylene group, a thiol group, an azido group, an oxirane group, an amine group, an amino group, a carboxylic acid group, a hydroxyl group, an alcohol group, an ether group, an ester group, and a ketone group, and

[0013] R 1 The alkylene group is selected from an alkylene group, a cyclohexylene group, a phenylene group, a methyleneoxy group, an ether group and an amide group, wherein the alkylene group, the ether group and the amide group all have 1 to 25 carbon atoms.

[0014] The first ligand may be derived from a compound represented by one selected from Formula 2-1 to Formula 2-36:

[0015]

[0016]

[0017] Here, n can be an integer from 1 to 12.

[0018] The first ligand may have a weight average molecular weight in the range of about 150 Daltons to about 500 Daltons.

[0019] The second ligand may be derived from a compound represented by one selected from Formula 3-1 to Formula 3-3:

[0020]

[0021] Among them, R 2 It can be selected from hydrogen, deuterium, hydroxyl, substituted or unsubstituted C 1 -C 60 Alkyl, substituted or unsubstituted C 2 -C 60 Alkenyl, substituted or unsubstituted C 2 -C 60 Alkynyl, substituted or unsubstituted C 1 -C 60 Alkoxy and substituted or unsubstituted C 1 -C 60 Alkyl ether group,

[0022] R 3 It can be selected from hydrogen, deuterium, hydroxyl, substituted or unsubstituted C 1 -C 60 Alkyl, substituted or unsubstituted C 2 -C 60 Alkenyl, substituted or unsubstituted C 2-C 60 Alkynyl, substituted or unsubstituted C 1 -C 60 Alkoxy and substituted or unsubstituted C 1 -C 60 an alkyl ether group, and

[0023] n can be an integer from 2 to 300.

[0024] The second ligand may include a polymer compound and may have a weight average molecular weight in the range of about 1,000 Daltons to about 90,000 Daltons.

[0025] The first ligand and the second ligand may be bonded to each other through a condensation reaction or a polymerization reaction.

[0026] The first ligand and the second ligand may be different from each other.

[0027] The LED may further include: an active layer disposed between the first semiconductor layer and the second semiconductor layer; and an electrode layer disposed on the second semiconductor layer.

[0028] The insulating layer may be arranged to at least partially surround (or completely surround) an outer surface of the first semiconductor layer, an outer surface of the second semiconductor layer, an outer surface of the active layer, and an outer surface of the electrode layer.

[0029] One end of the first semiconductor layer and one end of the electrode layer may be exposed without being covered by the insulating layer.

[0030] The insulating layer may include silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon oxynitride (SiO x N y ), aluminum nitride (AlN) and aluminum oxide (Al 2 O 3 ) is selected from at least one material.

[0031] The diameter of the LED may be in the range of about 0.1 μm to about 0.9 μm.

[0032] The length of the LED may be in the range of about 0.5 μm to about 9 μm.

[0033] The aspect ratio of the LED may be in the range of about 5 to about 10.

[0034] According to one or more embodiments, a display device includes: a substrate including a display area and a non-display area arranged around the display area; a first electrode and a second electrode, spaced apart from each other in the display area; and an LED, arranged between the first electrode and the second electrode, wherein the LED may include a first semiconductor layer, a second semiconductor layer, an active layer, an electrode layer and an insulating layer, wherein a first ligand is bound to a surface of the LED, and a second ligand is bound to the first ligand.

[0035] The first ligand may be bound to the insulating layer of the LED.

[0036] The first ligand may have a weight average molecular weight in the range of about 150 Daltons to about 500 Daltons.

[0037] The second ligand may include a polymer compound and may have a weight average molecular weight in the range of about 1,000 Daltons to about 90,000 Daltons.

[0038] The display device may further include a first contact electrode coupled to the first electrode and a second contact electrode coupled to the second electrode, wherein the LED may be disposed between the first contact electrode and the second contact electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and other aspects and features of certain disclosed embodiments will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0040] Figure 1 is a schematic perspective view of a display device according to an embodiment;

[0041] Figure 2 is a schematic plan view of a display device according to an embodiment;

[0042] Figure 3 It is shown Figure 1 A plan view of an example of pixels in a display area of ​​;

[0043] Figure 4 It is shown Figure 1 A plan view of an example of pixels in a display area of ​​;

[0044] Figure 5 is a schematic perspective view of a light emitting device (LED) according to an embodiment;

[0045] Figure 6 is a schematic cross-sectional view of a display device according to an embodiment; and

[0046] Figure 7 is a schematic perspective view of an LED according to an embodiment. DETAILED DESCRIPTION

[0047] Now will refer to embodiment in more detail, the example of embodiment is shown in the accompanying drawings, wherein the same reference numerals refer to the same element from time to time. In this regard, the embodiment provided can have different forms, and should not be construed as being limited to the description set forth herein. Therefore, the embodiment is only described below by reference to the accompanying drawings to explain the aspects of the embodiments of this specification. As used herein, the term "and / or" includes any combination and all combinations of one or more of the related listed items. Throughout this disclosure, the statement "at least one (kind / person) of a, b and c" represents only a, only b, only c, a and b both, a and c both, b and c both, a, b and c all or its variant.

[0048] Hereinafter, the embodiments will be described in more detail with reference to the accompanying drawings. When describing the embodiments with reference to the accompanying drawings, the same or corresponding elements are denoted by the same reference numerals, and a redundant description thereof will not be repeated.

[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. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0050] It will be understood that terms such as "comprising", "including" and "having" used herein indicate the presence of stated features or elements, but do not exclude the presence or addition of one or more other features or elements. It will be understood that when a layer, region or element is referred to as being "on" another layer, region or element, the layer, region or element may be "directly on" the other layer, region or element, or may be "indirectly on" the other layer, region or element with one or more intermediate layers, regions or elements therebetween.

[0051] For the convenience of description, the size of the components in the drawings may be exaggerated. In other words, since the size and thickness of the elements in the drawings may be arbitrarily shown for the convenience of description, the following embodiments are not limited thereto.

[0052] In the following examples, the x-axis, y-axis, and z-axis are not limited to the three axes of the rectangular coordinate system and can be interpreted in a broader sense. For example, the x-axis, y-axis, and z-axis can be perpendicular to each other, or can represent different directions that are not perpendicular to each other.

[0053] When a certain embodiment can be implemented differently, the set or specific process order can be performed differently from the described order. For example, two consecutively described processes can be performed substantially simultaneously or in the reverse order of the described order.

[0054] Figure 1 is a schematic perspective view of a display device 1 according to the embodiment.

[0055] Reference Figure 1 , the display device 1 may include a display area DA and a non-display area NDA arranged around the display area DA. For example, the non-display area NDA may surround the display area DA. The display device 1 may provide an image, for example, in a third direction (z direction) by using light emitted from a plurality of pixels P arranged in the display area DA, and the non-display area NDA may be an area in which an image is not displayed, or an area not designed to provide an image.

[0056] exist Figure 1 1 shows a display device 1 including a flat display surface, but the embodiment is not limited thereto. In an embodiment, the display device 1 may include a three-dimensional display surface, a curved display surface, or a flexible display surface that can be flat or curved.

[0057] When the display device 1 includes a three-dimensional display surface, the display device 1 may include a plurality of display areas indicating different directions. For example, the display device 1 may include a polygonal columnar display surface. In an embodiment, when the display device 1 includes a curved display surface, the display device 1 may be implemented in various suitable forms (such as a flexible display device, a foldable display device, or a rollable display device).

[0058] Figure 1 A display device 1 applicable to a mobile phone terminal is shown. In some embodiments, an electronic module, a camera module, and / or a power module, etc. mounted on a mainboard may be arranged in a bracket or a housing together with the display device 1 to constitute a mobile phone terminal. The display device 1 according to the embodiment may be applied to large electronic devices such as televisions and monitors, and small and medium-sized electronic devices such as tablet computers, car navigation systems, game consoles, and smart watches.

[0059] Figure 1 A case is shown in which the display area DA of the display device 1 is rectangular, but the present disclosure is not limited thereto. For example, the shape of the display area DA may be circular, elliptical, or a polygon such as a triangle or a pentagon.

[0060] Figure 2 is a schematic plan view of a display device 1 according to the embodiment.

[0061] Reference Figure 2 , the display device 1 may include a plurality of pixels P arranged in a display area DA. The pixels P may each include a light emitting device (LED) ( Figure 5 175) display element. The pixels P can each receive an LED ( Figure 5175) emits, for example, red light, green light, blue light or white light. The term "pixel P" as used herein may be understood as a pixel that emits one selected from the red light, green light, blue light and white light as described above.

[0062] The pixels P may each be electrically coupled to an external circuit disposed in the non-display area NDA. The first scan driving circuit 101, the first emission driving circuit 102, the second scan driving circuit 103, the terminal 104, the data driving circuit 105, the first power line 106, and the second power line 107 may be disposed in the non-display area NDA.

[0063] The first scan driving circuit 101 may provide a scan signal to the pixel P through the scan line SL. The first emission driving circuit 102 may provide an emission control signal to the pixel P through the emission control line EL. The second scan driving circuit 103 may be arranged in parallel with the first scan driving circuit 101, and the display area DA is between the second scan driving circuit 103 and the first scan driving circuit 101. Some pixels P arranged in the display area DA may be electrically coupled to the first scan driving circuit 101, and other pixels P arranged in the display area DA may be electrically coupled to the second scan driving circuit 103. In an embodiment, the second emission driving circuit may be arranged in parallel with the first emission driving circuit 102, and the display area DA is between the second emission driving circuit and the first emission driving circuit 102.

[0064] The first emission driving circuit 102 may be arranged in the non-display area NDA and may be spaced apart from the first scan driving circuit 101 in a first direction (x direction). In an embodiment, the first emission driving circuit 102 may be alternately arranged with the first scan driving circuit 101 in a second direction (y direction) crossing (e.g., intersecting) the first direction (x direction).

[0065] The terminal 104 may be arranged on one side of the substrate 100. The terminal 104 may be exposed without being covered by an insulating layer and thus electrically coupled to a printed circuit board (PCB) PCB. The terminal PCB-P of the PCB PCB may be electrically coupled to the terminal 104 of the display device 1. The PCB PCB may transmit a signal or power of the controller to the display device 1. The control signal generated by the controller may be transmitted to the first scan driving circuit 101, the first emission driving circuit 102, and the second scan driving circuit 103 through the PCB PCB. The controller may provide a first power supply voltage (ELVDD) and a second power supply voltage (ELVSS) to the first power supply line 106 and the second power supply line 107 through the first connection line 108 and the second connection line 109, respectively. The first power supply voltage (ELVDD) may be provided to the pixel P through the driving voltage line PL coupled to the first power supply line 106, and the second power supply voltage (ELVSS) may be provided to the counter electrode of the pixel P coupled to the second power supply line 107.

[0066] The data driving circuit 105 may be electrically coupled to the data line DL. A data signal of the data driving circuit 105 may be provided to the pixel P through the connection line 110 coupled to the terminal 104 and the data line DL coupled to the connection line 110.

[0067] Figure 2 The data driving circuit 105 is shown to be arranged on the PCB PCB, but in an embodiment, the data driving circuit 105 may be arranged on the substrate 100. For example, the data driving circuit 105 may be arranged between the terminal 104 and the first power line 106.

[0068] The first power line 106 may include a first sub-line 111 and a second sub-line 112 extending in parallel in a first direction (x direction) with the display area DA between the first sub-line 111 and the second sub-line 112. The second power line 107 may at least partially surround the display area DA in a ring shape having one side opening.

[0069] Figure 3 It is shown Figure 1 A plan view of an example of a pixel P in a display area DA, Figure 4 It is shown Figure 1 A plan view of an example of a pixel P in a display area DA, Figure 5 is a schematic perspective view of an LED according to an embodiment.

[0070] Reference Figure 3, the pixels P may each include a first sub-pixel PX1, a second sub-pixel PX2, and a third sub-pixel PX3. The first sub-pixel PX1 may emit a first light, the second sub-pixel PX2 may emit a second light, and the third sub-pixel PX3 may emit a third light. The first light may be red light, the second light may be green light, and the third light may be blue light, but the embodiment is not limited thereto. For example, the first sub-pixel PX1, the second sub-pixel PX2, and the third sub-pixel PX3 may emit light of the same (e.g., substantially the same) color. In addition, Figure 3 It is shown that the pixel P includes three sub-pixels, but the embodiment is not limited thereto.

[0071] The first subpixel PX1, the second subpixel PX2, and the third subpixel PX3 may include an emission area EMA and a non-emission area. The first subpixel PX1 may include a first emission area EMA1, the second subpixel PX2 may include a second emission area EMA2, and the third subpixel PX3 may include a third emission area EMA3. The emission area EMA may be defined as an area in which the LED 175 is arranged to emit light of a set or specific wavelength. The non-emission area may be defined as an area other than the emission area EMA. The non-emission area may be an area in which the LED 175 is not arranged and the light emitted from the LED 175 does not reach, and therefore does not emit light.

[0072] The first subpixel PX1 , the second subpixel PX2 , and the third subpixel PX3 may each include a first electrode 171 , a second electrode 173 , a contact electrode 174 , and an LED 175 .

[0073] The first electrode 171 may be a pixel electrode separated for each of the first subpixel PX1, the second subpixel PX2, and the third subpixel PX3 (e.g., divided into pixel electrodes corresponding to each of the first subpixel PX1, the second subpixel PX2, and the third subpixel PX3), and the second electrode 173 may be a common electrode commonly coupled to the first subpixel PX1, the second subpixel PX2, and the third subpixel PX3. In some embodiments, the first electrode 171 may be an anode electrode of the LED 175, and the second electrode 173 may be a cathode electrode of the LED 175.

[0074] The first electrode 171 and the second electrode 173 may respectively include electrode trunk portions 171S and 173S extending in the first direction (x direction) and one or more electrode branch portions 171B and 173B branched from the electrode trunk portions 171S and 173S and extending in the second direction (y direction).

[0075] The first electrode 171 may include a first electrode trunk portion 171S extending in the first direction (x direction) and at least one first electrode branch portion 171B branched from the first electrode trunk portion 171S and extending in the second direction (y direction).

[0076] The first electrode trunk 171S of one sub-pixel may be electrically separated from the first electrode trunk 171S of another sub-pixel adjacent in the first direction (x direction). The first electrode trunk 171S of one sub-pixel may be spaced apart from the first electrode trunk 171S of another sub-pixel adjacent in the first direction (x direction). The first electrode trunk 171S may be coupled to the thin film transistor through the first electrode contact hole CNTD.

[0077] The first electrode branch portions 171B may be arranged to be spaced apart from the second electrode trunk portion 173S in the second direction (y direction). The first electrode branch portions 171B may be arranged to be spaced apart from the second electrode branch portions 173B in the first direction (x direction).

[0078] The second electrode 173 may include a second electrode trunk portion 173S extending in the first direction (x direction) and second electrode branch portions 173B branched from the second electrode trunk portion 173S and extending in the second direction (y direction).

[0079] The second electrode trunk 173S of one subpixel may be connected to the second electrode trunk 173S of another subpixel adjacent in the first direction (x direction). The second electrode trunk 173S may be arranged to cross the first subpixel PX1, the second subpixel PX2, and the third subpixel PX3 in the first direction (x direction).

[0080] The second electrode branch portion 173B may be arranged to be spaced apart from the first electrode trunk portion 171S in the second direction (y direction). The second electrode branch portion 173B may be arranged to be spaced apart from the first electrode branch portion 171B in the first direction (x direction). The second electrode branch portion 173B may be arranged between the first electrode branch portions 171B in the first direction (x direction).

[0081] Figure 3 The first electrode branch portion 171B and the second electrode branch portion 173B are shown to extend in the second direction (y direction), but the embodiment is not limited thereto. For example, the first electrode branch portion 171B and the second electrode branch portion 173B may each have a partially bent or curved shape, and one electrode may be arranged to surround the other electrode, such as Figure 4 as shown in . Figure 4The following case is shown: wherein the second electrode 173 has a circular shape, the first electrode 171 is arranged to surround the second electrode 173, the annular hole HOL is formed between the first electrode 171 and the second electrode 173, and the second electrode 173 receives a cathode voltage through the second electrode contact hole CNTS. For example, the first electrode branch portion 171B and the second electrode branch portion 173B may each be formed in any suitable shape as long as at least a portion thereof is spaced apart to face each other to form a space for accommodating the LED 175 to be arranged.

[0082] The LED 175 may be arranged between the first electrode 171 and the second electrode 173. One end of the LED 175 may be electrically coupled to the first electrode 171, and the other end of the LED 175 may be electrically coupled to the second electrode 173. A plurality of LEDs 175 may be arranged to be spaced apart from each other. The LEDs 175 may be aligned substantially parallel to each other.

[0083] The LED 175 may have a rod shape, a wire shape, a tube shape, etc. For example, Figure 5 As shown in , LED 175 may have a cylindrical shape or a rod shape. However, the shape of LED 175 is not limited thereto, and LED 175 may have a polygonal columnar shape such as a cube shape, a rectangular parallelepiped shape, or a hexagonal columnar shape, or may extend in one direction to form a partially inclined outer surface. The length of LED 175 may be in the range of about 0.5 μm to about 9 μm or about 1 μm to about 6 μm, for example, in the range of about 3 μm to about 5 μm. In addition, the diameter of LED 175 may be in the range of about 0.1 μm to about 0.9 μm, and the aspect ratio of LED 175 may be in the range of about 5 to about 10.

[0084] The LED 175 of the first subpixel PX1 may emit a first light, the LED 175 of the second subpixel PX2 may emit a second light, and the LED 175 of the third subpixel PX3 may emit a third light. The first light may be red light having a central wavelength band in the range of about 620 nm to about 752 nm, the second light may be green light having a central wavelength band in the range of about 495 nm to about 570 nm, and the third light may be blue light having a central wavelength band in the range of about 450 nm to about 495 nm. In some embodiments, the LED 175 of the first subpixel PX1, the LED 175 of the second subpixel PX2, and the LED 175 of the third subpixel PX3 may emit light of substantially the same (e.g., approximately the same) color.

[0085] The contact electrode 174 may include a first contact electrode 174a and a second contact electrode 174b. The first contact electrode 174a and the second contact electrode 174b may each have a shape extending in the second direction (y direction).

[0086] The first contact electrode 174a may be disposed on the first electrode branch 171B and coupled to the first electrode branch 171B. The first contact electrode 174a may contact (e.g., physically contact) one end of the LED 175. The first contact electrode 174a may be disposed between the first electrode branch 171B and the LED 175. Thus, the LED 175 may be electrically coupled to the first electrode 171 through the first contact electrode 174a.

[0087] The second contact electrode 174b may be disposed on the second electrode branch 173B and coupled to the second electrode branch 173B. The second contact electrode 174b may contact (e.g., physically contact) the other end of the LED 175. The second contact electrode 174b may be disposed between the second electrode branch 173B and the LED 175. Thus, the LED 175 may be electrically coupled to the second electrode 173 through the second contact electrode 174b.

[0088] The width of the first contact electrode 174a (or the length of the first contact electrode 174a in the first direction (x direction)) may be greater than the width of the first electrode branch 171B (or the length of the first electrode branch 171B in the first direction (x direction)), and the width of the second contact electrode 174b (or the length of the second contact electrode 174b in the first direction (x direction)) may be greater than the width of the second electrode branch 173B (or the length of the second electrode branch 173B in the first direction (x direction)).

[0089] An outer bank 430 may be disposed between the first subpixel PX1, the second subpixel PX2, and the third subpixel PX3. The outer bank 430 may extend in the second direction (y direction). The length of each of the first subpixel PX1, the second subpixel PX2, and the third subpixel PX3 in the first direction (x direction) may be defined as a distance between the outer banks 430.

[0090] Reference Figure 5 , the LED 175 may include a first semiconductor layer 175a, a second semiconductor layer 175b, an active layer 175c, an electrode layer 175d, and an insulating layer 175e.

[0091] The first semiconductor layer 175a may be, for example, an n-type semiconductor having a first conductivity type. The first semiconductor layer 175a may be one or more selected from n-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. For example, when the LED 175 emits light in a blue wavelength band, the first semiconductor layer 175a may include a semiconductor having the formula Al x Ga y In 1-x-y The first semiconductor layer 175a may be doped with a first conductive type dopant such as Si, Ge, and / or Sn. For example, the first semiconductor layer 175a may be n-GaN doped with n-type Si.

[0092] The second semiconductor layer 175b may be, for example, a p-type semiconductor having a second conductivity type, and may be one or more selected from p-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. For example, when the LED 175 emits light in a green wavelength band, the second semiconductor layer 175b may include a p-type semiconductor having a formula of AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. x Ga y In 1-x-y The second semiconductor layer 175b may be doped with a second conductive type dopant such as Mg, Zn, Ca, Se, or Ba. In an embodiment, the second semiconductor layer 175b may be p-GaN doped with p-type Mg.

[0093] The active layer 175c may be arranged between the first semiconductor layer 175a and the second semiconductor layer 175b. The active layer 175c may include a material having a single quantum well structure or a multi-quantum well structure. When the active layer 175c includes a material having a multi-quantum well structure, a plurality of quantum layers and a plurality of well layers may be alternately stacked. In some embodiments, the active layer 175c 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, and may include different Group 3 to Group 5 semiconductor materials according to the wavelength band of the emitted light.

[0094] The active layer 175c can emit light by recombination of electron-hole pairs according to an electrical signal applied through the first semiconductor layer 175a and the second semiconductor layer 175b. The light emitted by the active layer 175c is not limited to light in a blue wavelength band, and the active layer 175c can emit light in a red wavelength band or a green wavelength band. For example, when the active layer 175c emits light in a blue wavelength band, the active layer 175c may include materials such as AlGaN and / or AlGaInN. In some embodiments, when the active layer 175c has a structure in which quantum layers and well layers are alternately stacked in a multi-quantum well structure, the quantum layers may include materials such as AlGaN and / or AlGaInN, and the well layers may include materials such as GaN and / or AlInN. For example, when the active layer 175c includes AlGaInN as a quantum layer and AlInN as a well layer, the active layer 175c may emit blue light having a central wavelength band in the range of about 450nm to about 495nm.

[0095] The light from the active layer 175c may be emitted from both sides as well as the longitudinal outer surface of the LED 175. For example, the direction of the light emitted by the active layer 175c is not limited to one direction.

[0096] The electrode layer 175d may be an ohmic contact electrode or a Schottky contact electrode (e.g., an electrode formed by a junction of a semiconductor and a metal). The LED 175 may include at least one electrode layer 175d. When the LED 175 is electrically coupled to the first electrode 171 or the second electrode 173, the electrode layer 175d may reduce the resistance between the LED 175 and the first electrode 171 or the second electrode 173. The electrode layer 175d may include a conductive metal or metal oxide material, such as at least one selected from 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 175d may include an n-type or p-type doped semiconductor material.

[0097] The insulating layer 175e may be arranged to at least partially surround (or completely surround) the outer surfaces of the first semiconductor layer 175a, the second semiconductor layer 175b, the active layer 175c, and the electrode layer 175d. The insulating layer 175e is used to protect the first semiconductor layer 175a, the second semiconductor layer 175b, the active layer 175c, and the electrode layer 175d. The insulating layer 175e may be formed to expose both ends of the LED 175 in the longitudinal direction. For example, one end of the first semiconductor layer 175a and one end of the electrode layer 175d may be exposed without being covered by the insulating layer 175e. The insulating layer 175e may only cover the outer surface of a portion of the first semiconductor layer 175a located at the active layer 175c and a portion of the second semiconductor layer 175b located at the active layer 175c, or may only cover the outer surface of a portion of the electrode layer 175d.

[0098] The insulating layer 175e may include a material having an insulating property, such as silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon oxynitride (SiO x N y ), aluminum nitride (AlN), aluminum oxide (Al 2 O 3 ) etc. An electrical short circuit that may occur when the active layer 175c is in direct contact (e.g., physical contact) with the first electrode 171 and the second electrode 173 through which an electrical signal is transmitted to the LED 175 can be prevented or the possibility or degree of such a short circuit can be reduced. In addition, because the insulating layer 175e protects the outer surface of the LED 175 including the active layer 175c, a reduction in luminous efficiency can be prevented or reduced.

[0099] Figure 6 is a schematic cross-sectional view of a display device according to an embodiment. For example, Figure 6 Along with Figure 3 The cross sections taken by the lines II-I' and II-II' correspond.

[0100] Reference Figure 6 , a display layer including a first buffer layer BF1 , a thin film transistor layer TFTL, an LED layer EML, and an encapsulation layer TFE may be disposed on the substrate SUB.

[0101] The first buffer layer BF1 may be formed on one surface of the substrate SUB. The first buffer layer BF1 may be formed on one surface of the substrate SUB to protect the thin film transistor 120 of the display layer and the LED layer EML from moisture that penetrates through the substrate SUB that is easily permeated with moisture. The first buffer layer BF1 may include a plurality of inorganic layers alternately stacked. For example, the first buffer layer BF1 may be a multilayer in which one or more inorganic layers selected from silicon nitride layers, silicon oxynitride layers, silicon oxide layers, titanium oxide layers, and aluminum oxide layers are alternately stacked. The first buffer layer BF1 may be omitted.

[0102] The thin film transistor layer TFTL may include a thin film transistor 120 , a first insulating layer 130 , an interlayer insulating layer 140 , a protective layer 150 , and a planarization layer 160 .

[0103] The thin film transistor 120 may be located on the first buffer layer BF1 , and may include an active layer 121 , a gate electrode 122 , a source electrode 123 , and a drain electrode 124 . Figure 6 A top gate structure is shown in which the gate electrode 122 of the thin film transistor 120 is located above the active layer 121, but the gate structure is not limited thereto. For example, the thin film transistor 120 may be formed as a bottom gate structure in which the gate electrode 122 is located below the active layer 121 or a double gate structure in which the gate electrode 122 is located above and below the active layer 121.

[0104] The active layer 121 may be arranged on the first buffer layer BF1. The active layer 121 may include an oxide semiconductor and / or a silicon semiconductor. When the active layer 121 includes an oxide semiconductor, the active layer 121 may include, for example, at least one oxide selected from indium (In), gallium (Ga), tin (Sn), zirconium (Zr), vanadium (V), hafnium (Hf), cadmium (Cd), germanium (Ge), chromium (Cr), titanium (Ti) and zinc (Zn). For example, the active layer 121 may be InSnZnO (ITZO) and / or InGaZnO (IGZO), etc. When the active layer 121 includes a silicon semiconductor, the active layer 121 may include, for example, amorphous silicon (α-Si) and / or low temperature polycrystalline silicon (LTPS) obtained by crystallizing amorphous silicon (α-Si).

[0105] The light blocking layer may be arranged on the first buffer layer BF1. The light blocking layer may be arranged to correspond to the thin film transistor 120. The light blocking layer may prevent the gate electrode 122, the source electrode 123, and the drain electrode 124 of the thin film transistor 120 from being visually recognized from the outside, or may reduce its visibility from the outside. A voltage may be applied to the light blocking layer. For example, the light blocking layer may be coupled to the source electrode 123 or the drain electrode 124 of the thin film transistor 120. Because the light blocking layer is supplied with a voltage related to the potential of the source electrode 123 or the drain electrode 124 of the thin film transistor 120, the thin film transistor 120 of the display device 1 may be stabilized. In an embodiment, the light blocking layer may be coupled to a separate line without being coupled to the source electrode 123 or the drain electrode 124 of the thin film transistor 120.

[0106] The first insulating layer 130 may be disposed on the active layer 121. The first insulating layer 130 may include silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) and zinc oxide (ZnO 2 ). The first insulating layer 130 may be a single layer or multiple layers including the above inorganic insulating materials.

[0107] The gate electrode 122 and the gate line may be disposed on the first insulating layer 130. The gate electrode 122 may overlap the active layer 121 and may be disposed on the first insulating layer 130. The gate electrode 122 and the gate line may each be a single layer or a multilayer including at least one metal selected from aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), and copper (Cu).

[0108] The first interlayer insulating layer 141 may be disposed on the gate electrode 122. The first interlayer insulating layer 141 may include silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2) and zinc oxide (ZnO 2 ) The first interlayer insulating layer 141 may be a single layer or multiple layers including the above-mentioned inorganic insulating materials.

[0109] The storage capacitor may be arranged on the first insulating layer 130. The storage capacitor may include a lower electrode and an upper electrode. The storage capacitor may overlap with the thin film transistor 120. The lower electrode of the storage capacitor may be arranged integrally with the gate electrode 122 of the thin film transistor 120. In an embodiment, the storage capacitor may not overlap with the thin film transistor 120, and the lower electrode may be an independent element separated from the gate electrode 122 of the thin film transistor 120.

[0110] The second interlayer insulating layer 142 may be disposed on the first interlayer insulating layer 141. The second interlayer insulating layer 142 may include silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) and zinc oxide (ZnO 2 The second interlayer insulating layer 142 may be a single layer or multiple layers including the above-mentioned inorganic insulating materials.

[0111] The source electrode 123 and the drain electrode 124 may be arranged on the second interlayer insulating layer 142. The source electrode 123 and the drain electrode 124 may each be coupled to the active layer 121 through a contact hole passing through the first insulating layer 130 and the interlayer insulating layer 140. The source electrode 123 and the drain electrode 124 may each include a conductive material including molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), etc., and may each be a single layer or a multilayer including the above materials. For example, the source electrode 123 and the drain electrode 124 may each have a multilayer structure of Ti / Al / Ti.

[0112] The protective layer 150 may be disposed on the source electrode 123 and the drain electrode 124 to insulate the thin film transistor 120. The protective layer 150 may include silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2) and zinc oxide (ZnO 2 The protective layer 150 may be a single layer or multiple layers including the above-mentioned inorganic insulating materials.

[0113] The planarization layer 160 may be disposed on the protective layer 150. The planarization layer 160 may have a flat upper surface so that an electrode disposed thereon is flatly formed. The planarization layer 160 may include an organic layer such as acrylic resin, epoxy resin, phenolic resin, polyamide resin, and / or polyimide resin.

[0114] The LED layer EML may be disposed on the thin film transistor layer TFTL and may include a first inner bank 410 , a second inner bank 420 , an outer bank 430 , a first electrode 171 , a second electrode 173 , a contact electrode 174 , an LED 175 , a second insulating layer 181 , a third insulating layer 182 , and a fourth insulating layer 183 .

[0115] The first inner bank 410, the second inner bank 420, and the outer bank 430 may be arranged on the planarization layer 160. The first inner bank 410, the second inner bank 420, and the outer bank 430 may protrude from the upper surface of the planarization layer 160. The first inner bank 410, the second inner bank 420, and the outer bank 430 may have a trapezoidal cross-sectional shape, but the embodiment is not limited thereto. The lower surfaces of the first inner bank 410, the second inner bank 420, and the outer bank 430 may contact the upper surface of the planarization layer 160 (e.g., physically contact the upper surface of the planarization layer 160), the upper surfaces of the first inner bank 410, the second inner bank 420, and the outer bank 430 may face the lower surfaces of the first inner bank 410, the second inner bank 420, and the outer bank 430, and the side surfaces of the first inner bank 410, the second inner bank 420, and the outer bank 430 may be between the upper surface and the lower surface of the first inner bank 410, the second inner bank 420, and the outer bank 430. A side surface of the first inner bank 410 , a side surface of the second inner bank 420 , and a side surface of the outer bank 430 may be inclined.

[0116] The first inner bank 410 and the second inner bank 420 may be spaced apart from each other. The first inner bank 410 and the second inner bank 420 may each include an organic layer such as acrylic resin, epoxy resin, phenolic resin, polyamide resin, and / or polyimide resin.

[0117] The first electrode branch 171B may be disposed on the first inner bank 410, and the second electrode branch 173B may be disposed on the second inner bank 420. The first electrode branch 171B may be coupled to the first electrode trunk 171S, and the first electrode trunk 171S may be coupled to the drain electrode 124 of the thin film transistor 120 through the first electrode contact hole CNTD. Therefore, the first electrode 171 may receive a voltage from the drain electrode 124 of the thin film transistor 120.

[0118] The first electrode 171 and the second electrode 173 may each include a conductive material having a high reflectivity. For example, the first electrode 171 and the second electrode 173 may each include a metal such as silver (Ag), copper (Cu) and / or aluminum (Al). Therefore, light emitted from the LED 175 and traveling to the first electrode 171 and the second electrode 173 may be reflected by the first electrode 171 and the second electrode 173 and travel over the LED 175.

[0119] The second insulating layer 181 may be arranged on the first electrode 171 and the second electrode branch 173B. The second insulating layer 181 may be arranged to cover the first electrode trunk 171S, the first electrode branch 171B arranged on the side surface of the first inner bank 410, and the second electrode branch 173B arranged on the side surface of the second inner bank 420. The first electrode branch 171B arranged on the upper surface of the first inner bank 410 and the second electrode branch 173B arranged on the upper surface of the second inner bank 420 may be exposed without being covered by the second insulating layer 181. The second insulating layer 181 may be arranged on the outer bank 430. The second insulating layer 181 may include a silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) and zinc oxide (ZnO 2 ) The second insulating layer 181 may be a single layer or multiple layers including the above inorganic insulating materials.

[0120] The LED 175 may be disposed on the second insulating layer 181 between the first inner bank 410 and the second inner bank 420 . Figure 6 A single LED 175 is shown disposed between the first inner bank 410 and the second inner bank 420 , but the embodiment is not limited thereto. 5 to 15 LEDs 175 (eg, 8 to 12 LEDs 175 ) may be disposed between the first inner bank 410 and the second inner bank 420 .

[0121] The LED layer EML according to the embodiment can be formed by applying a voltage between the first electrode 171 and the second electrode 173 formed on the substrate SUB to form an electric field, and dropping an ink composition containing LED 175 on the first electrode 171 and the second electrode 173 so that the LED 175 is aligned on the first electrode 171 and the second electrode 173 by the electric field.

[0122] The third insulating layer 182 may be disposed on the LED 175. The third insulating layer 182 may include silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) and zinc oxide (ZnO 2 The third insulating layer 182 may be a single layer or multiple layers including the above-mentioned inorganic insulating materials.

[0123] The first contact electrode 174a may be disposed on the first electrode branch 171B exposed without being covered by the second insulating layer 181 and may contact (eg, physically contact) one end of the LED 175. The first contact electrode 174a may also be disposed on the third insulating layer 182.

[0124] The fourth insulating layer 183 may be disposed on the first contact electrode 174a. The fourth insulating layer 183 may be disposed to cover the first contact electrode 174a to electrically separate the first contact electrode 174a from the second contact electrode 174b. The fourth insulating layer 183 may include silicon oxide (SiO 2 ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) and zinc oxide (ZnO 2 The fourth insulating layer 183 may be a single layer or multiple layers including the above-mentioned inorganic insulating materials.

[0125] The second contact electrode 174b may be disposed on the second electrode branch 173B exposed without being covered by the second insulating layer 181, and may contact (e.g., physically contact) the other end of the LED 175. The second contact electrode 174b may also be disposed on the third insulating layer 182 and the fourth insulating layer 183.

[0126] The encapsulation layer TFE may be arranged on the LED layer EML. The encapsulation layer TFE may include at least one inorganic encapsulation layer and at least one organic encapsulation layer. In an embodiment, the encapsulation layer TFE may include a first inorganic encapsulation layer, a second inorganic encapsulation layer, and an organic encapsulation layer arranged between the first inorganic encapsulation layer and the second inorganic encapsulation layer. The first inorganic encapsulation layer and the second inorganic encapsulation layer may each include one or more inorganic insulating materials selected from aluminum oxide, titanium oxide, tantalum oxide, hafnium oxide, zinc oxide, silicon oxide, silicon nitride, and silicon oxynitride. The organic encapsulation layer may include a polymer material. The polymer material may include acrylic resin, epoxy resin, polyimide and / or polyethylene, etc. In another embodiment, the encapsulation layer TFE may be provided as an encapsulation substrate.

[0127] Figure 7 is a schematic perspective view of an LED 175 according to an embodiment.

[0128] Reference Figure 7 , the LED 175 according to the embodiment may include a first ligand 176 bonded to a surface of the LED 175 and a second ligand 177 bonded to the first ligand 176. For example, the LED 175 may include a first ligand 176 bonded to an insulating layer 175e of the LED 175 and a second ligand 177 bonded to the first ligand 176. Figure 7 A single first ligand 176 is shown to be bonded to the LED 175 and a single second ligand 177 is bonded to the first ligand 176, but the embodiment is not limited thereto. A plurality of first ligands 176 may be bonded to the surface of the LED 175 along the periphery of the LED 175, and a plurality of second ligands 177 may be bonded to the first ligands 176 bonded to the surface of the LED 175, respectively.

[0129] The first ligand 176 may be derived from (or selected from) a compound represented by Formula 1:

[0130] Formula 1

[0131] A 1 -R 1 -A 2

[0132] In formula 1,

[0133] A 1 is selected from alkylsiloxane groups, alkylphosphonic acid groups, catechol groups, alkylcatechol groups, carboxylic acid groups, thiol groups and amine groups,

[0134] A 2 is selected from a halogen group, a vinyl group, an acetylene group, a thiol group, an azido group, an oxirane group, an amine group, an amino group, a carboxylic acid group, a hydroxyl group, an alcohol group, an ether group, an ester group, and a ketone group, and

[0135] R 1 The alkylene group is selected from the group consisting of an alkylene group, a cyclohexylene group, a phenylene group, a methyleneoxy group, an ether group, and an amide group, wherein each of the alkylene group, the ether group, and the amide group has 1 to 25 (e.g., 1 to 12) carbon atoms. The ether group and the amide group may be divalent groups.

[0136] In an embodiment, the first ligand 176 may be derived from (or selected from) a compound represented by one selected from Formula 2-1 to Formula 2-36:

[0137]

[0138]

[0139]

[0140] n is an integer of 1-12.

[0141] In an embodiment, the first ligand 176 may have a weight average molecular weight in a range of about 150 Daltons to about 500 Daltons. For example, the first ligand 176 may be an organic monomer.

[0142] The second ligand 177 may be derived from (or selected from) a compound represented by one selected from Formula 3-1 to Formula 3-3:

[0143]

[0144]

[0145] R 2 is selected from hydrogen, deuterium, hydroxyl, substituted or unsubstituted C 1 -C 60 Alkyl, substituted or unsubstituted C 2 -C 60 Alkenyl, substituted or unsubstituted C 2 -C 60 Alkynyl, substituted or unsubstituted C 1 -C 60 Alkoxy and substituted or unsubstituted C 1 -C 60 Alkyl ether group,

[0146] R 3 is selected from hydrogen, deuterium, hydroxyl, substituted or unsubstituted C 1 -C 60 Alkyl, substituted or unsubstituted C 2 -C 60 Alkenyl, substituted or unsubstituted C 2 -C 60 Alkynyl, substituted or unsubstituted C 1-C 60 Alkoxy and substituted or unsubstituted C 1 -C 60 an alkyl ether group, and

[0147] n is an integer of 2 to 300, for example, an integer of 2 to 100.

[0148] In an embodiment, the second ligand 177 may be a polymer compound and may have a weight average molecular weight in the range of about 1,000 Daltons to about 90,000 Daltons. For example, the second ligand 177 may be a compound different from the first ligand 176 .

[0149] In an embodiment, the first ligand 176 and the second ligand 177 may be bonded to each other through a condensation reaction or a polymerization reaction. For example, as the first ligand 176 and the second ligand 177 are bonded to each other, the length of the chain may increase.

[0150] Hereinafter, an LED according to an embodiment will be described in more detail with reference to examples.

[0151] Example

[0152] An LED in which a first ligand was bonded to the surface of the LED and a second ligand was bonded to the first ligand (Example 1) and an LED in which no ligand was bonded (Comparative Examples 1 to Comparative Examples 7) were manufactured, and the degree of alignment according to the characteristics (dielectric constant and viscosity) of the solvent included in the ink composition was measured. The results are shown in Table 1 below.

[0153] Table 1

[0154]

[0155]

[0156] Referring to Table 1, it can be seen that the LED (Example 1) in which the first ligand is bound to the surface of the LED and the second ligand is bound to the first ligand has an improved degree of alignment compared to the LED (Comparative Examples 1 to Comparative Examples 7) in which no ligand is bound. The LED (Example 1) in which the first ligand is bound to the surface of the LED and the second ligand is bound to the first ligand can have a high degree of alignment even when a solvent with a low viscosity is used, the degree of polarity of the solvent can be adjusted according to the structures of the first ligand and the second ligand, and can have a high degree of alignment even when a solvent with a low dielectric constant is used.

[0157] When an ink composition including an LED is dropped onto a first electrode and a second electrode so that the LED is aligned between the first electrode and the second electrode by an electric field, since the LED has low dispersibility to the ink composition, the LED is not dispersed in the ink composition and settles downward, thereby reducing the degree of alignment in which the LED is aligned between the first electrode and the second electrode.

[0158] According to one or more embodiments, an LED may be provided in which a first ligand 176 is bonded to a surface of an LED 175 and a second ligand 177 is bonded to the first ligand 176, thereby improving the dispersibility of the LED to the ink composition and improving the ratio of the LED to be aligned between a pair of electrodes. In addition, according to one or more embodiments, a display device including the LED may be provided.

[0159] For example, the surface of the LED is first modified by using a first ligand (organic monomer) having a small steric effect, and a second ligand (organic polymer) is bonded to the first ligand by a condensation reaction, thereby increasing the chain length of the ligand. Therefore, the dispersibility of the LED to the ink composition can be improved, and the ratio of the LED alignment between a pair of electrodes can be improved.

[0160] As described above, according to one or more embodiments, a display device can be realized in which a first ligand is bonded to the surface of an independently manufactured nano-scale or micro-scale LED and a second ligand is bonded to the first ligand, thereby improving the dispersibility of the LED to the ink composition and improving the ratio of the LED to be aligned between a pair of electrodes. However, the scope of the disclosure is not limited to these effects.

[0161] [General Definition of Substituents]

[0162] As used herein, the term "C 1 -C 60 "Alkyl" refers to a linear or branched aliphatic saturated hydrocarbon monovalent group having 1 to 60 carbon atoms, and examples thereof include methyl, ethyl, propyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl and hexyl. As used herein, the term "C 1 -C 60 "Alkylene" refers to a group having a C 1 -C 60 The structure of an alkyl group is a divalent group of the same structure.

[0163] As used herein, the term "C 2 -C 60 "Alkenyl" refers to 2 -C 60The term "C" as used herein refers to a hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminal of the alkyl group, examples of which include ethenyl, propenyl, and butenyl. 2 -C 60 "Alkenylene" refers to a 2 -C 60 The structure of the alkenyl group is a divalent group of the same structure.

[0164] As used herein, the term "C 2 -C 60 "Alkynyl" refers to a C 2 -C 60 The term "C" as used herein refers to a hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminal of the alkyl group, examples of which include ethynyl and propynyl. 2 -C 60 "Alkyne" refers to a 2 -C 60 The structure of the alkynyl group is a divalent group of the same structure.

[0165] As used herein, the term "C 1 -C 60 "Alkoxy" refers to -OA 101 (Among them, A 101 C 1 -C 60 The invention further comprises a monovalent group represented by an alkyl group, and examples thereof include a methoxy group, an ethoxy group and an isopropoxy group.

[0166] The process of bonding the first ligand to the surface of the insulating layer and the process of bonding the second ligand to the first ligand are not specific processes but processes using general chemical reactions. In addition, the solvent used in the process depends on the type of ligand.

[0167] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for limiting purposes. The description of features or aspects in each embodiment should generally be considered to be applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the claims and their equivalents.

Claims

1. A light emitting device, comprising: a first semiconductor layer; a second semiconductor layer, facing the first semiconductor layer; an insulating layer arranged to at least partially surround an outer surface of the first semiconductor layer and an outer surface of the second semiconductor layer; as well as a first ligand and a second ligand, wherein the first ligand is bound to the surface of the insulating layer, and the second ligand is bound to the first ligand, Wherein, the second ligand is derived from a compound represented by one selected from Formula 3-1 to Formula 3-3: <Formula 3-1> <Formula 3-2> <Formula 3-3> ， wherein R2 is selected from hydrogen, deuterium, hydroxyl, substituted or unsubstituted C1-C 60 Alkyl, substituted or unsubstituted C2-C 60 Alkenyl, substituted or unsubstituted C2-C 60 Alkynyl, substituted or unsubstituted C1-C 60 Alkoxy and substituted or unsubstituted C1-C 60 Alkyl ether group, R3 is selected from hydrogen, deuterium, hydroxyl, substituted or unsubstituted C1-C 60 Alkyl, substituted or unsubstituted C2-C 60 Alkenyl, substituted or unsubstituted C2-C 60 Alkynyl, substituted or unsubstituted C1-C 60 Alkoxy and substituted or unsubstituted C1-C 60 an alkyl ether group, and n is an integer of 2-300.

2. The light emitting device according to claim 1, wherein: The first ligand is derived from a compound represented by formula 1: Formula 1 Among them, in formula 1, A1 is selected from alkylsiloxane groups, alkylphosphonic acid groups, catechol groups, alkylcatechol groups, carboxylic acid groups, thiol groups and amine groups, A2 is selected from the group consisting of a halogen group, a vinyl group, an acetylene group, a thiol group, an azido group, an oxirane group, an amine group, an amino group, a carboxylic acid group, a hydroxyl group, an alcohol group, an ether group, an ester group, and a ketone group, and R1 is selected from an alkylene group, a cyclohexylene group, a phenylene group, a methyleneoxy group, an ether group and an amide group, wherein the alkylene group, the ether group and the amide group all have 1 to 25 carbon atoms.

3. The light emitting device according to claim 1, wherein: The first ligand is derived from a compound represented by one selected from Formula 2-1 to Formula 2-36: <Formula 2-1> <Formula 2-2> <Formula 2-3> <Formula 2-4> <Formula 2-5> <Formula 2-6> <Formula 2-7> <Formula 2-8> <Formula 2-9> <Formula 2-10> <Formula 2-11> <Formula 2-12> <Formula 2-13> <Formula 2-14> <Formula 2-15> <Formula 2-16> <Formula 2-17> <Formula 2-18> <Formula 2-19> <Formula 2-20> <Formula 2-21> <Formula 2-22> <Formula 2-23> <Formula 2-24> <Formula 2-25> <Formula 2-26> <Formula 2-27> <Formula 2-28> <Formula 2-29> <Formula 2-30> <Formula 2-31> <Formula 2-32> <Formula 2-33> <Formula 2-34> <Formula 2-35> <Formula 2-36> Here, n is an integer from 1 to 12.

4. The light emitting device according to claim 1, wherein: The first ligand has a weight average molecular weight in the range of 150 Daltons to 500 Daltons.

5. The light emitting device according to claim 1, wherein: The second ligand includes a polymer compound and has a weight average molecular weight ranging from 1,000 Daltons to 90,000 Daltons.

6. The light emitting device according to claim 1, wherein: The first ligand and the second ligand are bonded to each other through a condensation reaction or a polymerization reaction.

7. The light emitting device according to claim 1, wherein: The first ligand and the second ligand are different from each other.

8. The light emitting device according to claim 1, further comprising: an active layer, arranged between the first semiconductor layer and the second semiconductor layer; as well as The electrode layer is arranged on the second semiconductor layer.

9. The light emitting device according to claim 8, wherein: The insulating layer is arranged to at least partially surround the outer surface of the first semiconductor layer, the outer surface of the second semiconductor layer, the outer surface of the active layer, and the outer surface of the electrode layer.

10. The light emitting device according to claim 9, wherein: One end of the first semiconductor layer and one end of the electrode layer are exposed without being covered by the insulating layer.

11. The light emitting device according to claim 1, wherein: The insulating layer includes at least one material selected from silicon oxide, silicon nitride, silicon oxynitride, aluminum nitride, and aluminum oxide.

12. The light emitting device according to claim 1, wherein: The diameter of the light emitting device is in the range of 0.1 μm to 0.9 μm.

13. The light emitting device according to claim 12, wherein: The length of the light emitting device is in the range of 0.5 μm to 9 μm.

14. The light emitting device according to claim 13, wherein: The aspect ratio of the light emitting device is in the range of 5 to 10.

Images