Patent Description:
Light-emitting diodes (LEDs) are elements that convert electrical signals into a form of light such as infrared rays, visible light, or the like using the characteristics of compound semiconductors, and the LEDs are used in home appliances, remote controllers, electronic boards, various types of automation devices, and the like and an application range of the LEDs is gradually expanding.

Furthermore, attempts to apply LEDs to a display device are expanding. For example, attempts to use the LEDs as a backlight of a display device or to directly implement a self-emissive display device by miniaturizing the LEDs into units of fine pixels capable of displaying an image are expanding.

Accordingly, in order to reduce the size of the LEDs and secure sufficient brightness to be used in various types of devices, a structure in which several LEDs may be integrated is required.

<CIT> relates to an ultra-small LED electrode assembly.

<CIT> relates to a pixel structure, a display device including such a pixel structure and method of manufacturing such a pixel structure.

<CIT> relates to a display apparatus and method of manufacturing such a display apparatus.

Walls are formed around a light-emitting diode and a reflective electrode is formed on the wall to reflect light emitted from a side surface of the light-emitting diode forward, thereby increasing light emission efficiency of the light-emitting diode.

However, a process of manufacturing a light-emitting device may be complicated due to the formation of the walls, the formation of the reflective electrodes, and the like.

Accordingly, the present invention is directed to providing a light-emitting device that is allowed to be manufactured through a more simplified process.

Further, the present invention is also directed to providing a light-emitting device with improved light emission efficiency.

The scope of the present invention is not limited to the above-described objects and other unmentioned objects may be clearly understood by those skilled in the art from the following descriptions.

According to an embodiment of the present disclosure, a light-emitting device comprises a substrate, a first electrode which is disposed on the substrate, includes holes, and has inclined surfaces formed along peripheries of the holes, second electrodes which are disposed on the substrate and each disposed in one of the holes of the first electrode and light-emitting elements which are disposed between the first electrode and the second electrodes and electrically connected to the first electrode and the second electrodes.

The light-emitting device may further comprise a transistor electrically connected to the first electrode and a power line electrically connected to the second electrodes.

The power line may be disposed below the substrate, and each of the second electrodes may be electrically connected to the power line through a through-hole which passes through the substrate to expose the power line.

The first electrode includes a first metal bonding layer, a metal conductive layer disposed on the first metal bonding layer, and a second metal bonding layer disposed on the metal conductive layer, the metal conductive layer has a thickness which is greater than a thickness of the first metal bonding layer and greater than a thickness of the second metal bonding layer, and the inclined surfaces are formed on the metal conductive layer.

The metal conductive layer may include a reflective material, and light emitted from the light-emitting elements may be reflected by the metal conductive layer.

An inclination angle formed by the inclined surface based on the substrate may be less than <NUM> degrees and greater than <NUM> degrees.

A first taper angle of an inner sidewall of the metal conductive layer may be different from a second taper angle of an outer sidewall of the metal conductive layer, and the inner sidewall of the metal conductive layer may be adjacent to the second electrode.

The inner sidewall of the metal conductive layer may be formed through a process different from a process of forming the outer sidewall of the metal conductive layer.

The light-emitting device may further comprise a first pixel wall disposed on the first electrode, wherein the first pixel wall may include bank holes corresponding to the holes.

The light-emitting device may further comprise a second pixel wall disposed on each of the second electrodes.

Each of the second electrodes may include a central portion, a first peripheral portion which is spaced apart from the central portion, extends along an edge of the central portion, and has both end portions spaced apart from each other, and a first connection portion configured to connect the central portion to the first peripheral portion, and the first electrode may include a main body portion including the holes, a second peripheral portion which extends along the edge of the central portion between the central portion and the first peripheral portion and has both end portions with the first connection portion interposed therebetween, and a second connection portion which crosses the end portions of the first peripheral portion to connect the second peripheral portion to the main body portion.

The central portion may have a circular planar shape, and each of the first peripheral portion and the second peripheral portion may have a ring shape in which a portion is cut in a top view.

The light-emitting device may further comprise a first insulating layer disposed below the light-emitting elements between the first electrode and the second electrodes, an organic insulating layer configured to cover the light-emitting elements and expose both end portions of each of the light-emitting elements, a first contact electrode which is electrically connected to the first electrode, is disposed on the organic insulating layer, and is in contact with a first end portion of each of the light-emitting elements, and a second contact electrode which is electrically connected to the second electrodes, is disposed on the organic insulating layer, and is in contact with a second end portion of each of the light-emitting elements.

The first contact electrode and the second contact electrode may face each other and be disposed to be spaced apart from each other, and the light-emitting device may further comprise a second insulating layer which covers the first contact electrode and the second contact electrode and be disposed in a region in which the first contact electrode is spaced apart from the second contact electrode.

The first contact electrode and the second contact electrode may be disposed to be substantially coplanar.

Each of the light-emitting elements may have a cylindrical shape, and a portion of a lower surface of each of the light-emitting elements may be in direct contact with the first insulating layer.

According to an embodiment not forming part of the invention as claimed, a method of manufacturing a light-emitting device comprises forming an electrode layer on a substrate, patterning the electrode layer and forming first pixel electrodes disposed independently of each other and unseparated electrode patterns surrounding the first pixel electrodes, arranging light-emitting elements on the unseparated electrode patterns and the first pixel electrodes, forming an electric field between the unseparated electrode patterns and the first pixel electrodes and aligning the light-emitting elements and patterning the unseparated electrode patterns and forming a second pixel electrode surrounding at least one of the first pixel electrodes.

The unseparated electrode patterns may have a mesh structure.

The forming of the first pixel electrodes and the unseparated electrode patterns may include forming a first insulating layer which is disposed on the first pixel electrodes and the unseparated electrode patterns and disposed between the first pixel electrodes and the unseparated electrode patterns, and the light-emitting elements may be disposed on the first insulating layer.

The forming of the first pixel electrodes and the unseparated electrode patterns may further include forming a first pixel wall on the first insulating layer, and the first pixel wall may overlap the unseparated electrode pattern and surround each of the first pixel electrodes in a top view.

The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

According to embodiments of the present invention, a light-emitting device includes a first electrode and a second electrode which function as an integrated reflective electrode, and thus the light-emitting device can be manufactured through a more simplified process.

Further, the first electrode is disposed to surround the second electrode and a light-emitting element is disposed between the first electrode and the second electrode, and thus an arrangement area of a region in which the light-emitting element is disposed can be increased and light emission efficiency can be improved.

According to embodiments not forming part of the invention as claimed, in a method of manufacturing a light-emitting device, an electric field is formed using an unseparated electrode pattern before a first electrode is patterned, and thus alignment efficiency of a light-emitting element can be improved.

Effects according to the embodiments of the present invention are not limited by the content exemplified above and more various effects are included in the specification.

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. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

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. The same reference numbers indicate the same components throughout the specification.

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 instance, a first element discussed below could be termed a second element without departing from the teachings of the present invention. Similarly, the second element could also be termed the first element.

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings.

<FIG> is a plan view of a light-emitting device according to an embodiment.

Referring to <FIG>, a light-emitting device <NUM> may include a first pixel PX1, a second pixel PX2, and a third pixel PX3. The first pixel PX1, the second pixel PX2, and the third pixel PX3 may be repeatedly arranged in a first direction D1.

Each of the first pixel PX1, the second pixel PX2, and the third pixel PX3 may be a light-emitting unit of a minimum unit that emits light. When the light-emitting device <NUM> displays an image, each of the first pixel PX1, the second pixel PX2, and the third pixel PX3 may be a light-emitting unit of a minimum unit that displays a color included in the image. The first pixel PX1, the second pixel PX2, and the third pixel PX3 may emit pieces of light with different colors. For example, the first pixel PX1 may emit light with a first color (e.g., red), the second pixel PX2 may emit light with a second color (e.g., green), and the third pixel PX3 may emit light with a third color (e.g., blue). Colors may be realized through a combination of the colors emitted by the first pixel PX1, the second pixel PX2, and the third pixel PX3. The first pixel PX1, the second pixel PX2, and the third pixel PX3 will be described below with reference to <FIG>.

The first pixel PX1, the second pixel PX2, and the third pixel PX3 may be substantially the same except for colors of the pieces of emitted light. Hereinafter, common characteristics of the first pixel PX1, the second pixel PX2, and the third pixel PX3 will be described based on the first pixel PX1, and overlapping descriptions will not be repeated.

The first pixel PX1 includes a first electrode <NUM> (or a pixel electrode), second electrodes <NUM> (or common electrodes), and light-emitting elements <NUM>, which are formed on a circuit board <NUM> (or a substrate). The circuit board <NUM> is included in the light-emitting device <NUM>.

The circuit board <NUM> (or the substrate) may include a transistor (not illustrated) that supplies a current to the first pixel PX1 and a power electrode <NUM>. The circuit board <NUM> will be described below with reference to <FIG>.

The first electrode <NUM> is disposed on the circuit board <NUM>. The first electrode <NUM> may have a rectangular shape, in which a length in the first direction D1 is smaller than a length in a second direction D2, but the above shape is an example, and the present disclosure is not limited thereto.

The first electrode <NUM> includes a plurality of holes. For example, the first electrode <NUM> may include a first hole HOL1, a second hole HOL2, and a third hole HOL3 which are arranged in the second direction D2, but the present invention is not limited thereto. For example, the first electrode <NUM> may include two holes, or four or more holes.

Hereinafter, an example in which the first electrode <NUM> includes the first hole HOL1, the second hole HOL2, and the third hole HOL3 will be described.

Each of the first hole HOL1, the second hole HOL2, and the third hole HOL3 may form a closed loop in a plan view and may not be connected to the outside.

As illustrated in <FIG>, each of the first hole HOL1, the second hole HOL2, and the third hole HOL3 may have a circular planar shape. However, the above shape is exemplary and the present invention is not limited thereto. Each of the first hole HOL1, the second hole HOL2, and the third hole HOL3 is not limited in a shape as long as the shape can provide a space in which the second electrode <NUM> is disposed. For example each of the first hole HOL1, the second hole HOL2, and the third hole HOL3 may have a planar shape such as an elliptical shape, a polygonal shape of a rectangular shape or more.

The second electrode <NUM> is disposed on the circuit board <NUM>. A plurality of second electrodes <NUM> is provided, for example, three second electrodes <NUM> are provided to correspond to the first to third holes HOL1, HOL2, and HOL3. Each of the second electrodes <NUM> is positioned in one of the first to third holes HOL1, HOL2, and HOL3. The second electrodes <NUM> may be surrounded by the first electrode <NUM>.

The light-emitting elements <NUM> are disposed between the first electrode <NUM> and the second electrodes <NUM> on the circuit board <NUM> and are electrically connected to the first electrode <NUM> and the second electrodes <NUM>. For example, the light-emitting elements <NUM> may be repeatedly arranged along an edge of the second electrode <NUM> in the first hole HOL1 of the first electrode <NUM>. The light-emitting elements <NUM> may be arranged irregularly (or at non-regular intervals), but the present invention is not limited thereto. For example, the light-emitting elements <NUM> may be repeatedly arranged at regular intervals (or at an isometric angle based on an area center of the second electrode <NUM>).

The second electrode <NUM> may be electrically connected to the power electrode <NUM>.

The power electrode <NUM> may be disposed inside the circuit board <NUM>, may extend in the second direction D2, and may be connected to the second electrodes <NUM>. In the circuit board <NUM>, contact holes 319_2 (or fifth contact holes) which pass through an upper surface of the circuit board <NUM> to expose the power electrode <NUM> may be formed, and the second electrodes <NUM> may be electrically connected to the power electrode <NUM> through the contact holes 319_2 (or the fifth contact holes).

As described with reference to <FIG>, the first electrode <NUM> includes the first to third holes HOL1, HOL2, and HOL3, each of the second electrodes <NUM> is disposed in one of the first to third holes HOL1, HOL2, and HOL3, and the light-emitting elements <NUM> may be repeatedly disposed along the edges of the second electrodes <NUM> in the first to third holes HOL1, HOL2, and HOL3. In this case, an arrangement area (or an arrangement space) in which the light-emitting elements <NUM> are disposed between the first electrode <NUM> and the second electrodes <NUM> may be greater than an arrangement area (i.e., an area of a region in which the light-emitting elements are disposed) in which light-emitting elements are disposed between electrodes having a linear form, more light-emitting elements <NUM> may be disposed, and thus maximum luminance of the light-emitting device <NUM> may be improved.

Meanwhile, in <FIG>, the power electrode <NUM> is illustrated as extending in the second direction D2 (e.g., in a column direction) and crossing each of the first to third pixels PX1, PX2, and PX3, but the above configuration is exemplary and the power electrode <NUM> is not limited thereto. For example, the power electrode <NUM> may extend in a row direction or may be arranged in the form of a mesh.

<FIG> is a cross-sectional view illustrating an example of the light-emitting device taken along line I-I' of <FIG>.

Referring to <FIG>, the light-emitting device <NUM> may include a circuit board <NUM> (or a circuit element layer) and a light-emitting element layer <NUM>. The circuit board <NUM> includes a substrate <NUM>, a first transistor <NUM> (or a first thin film transistor, a first switching element), and a second transistor <NUM> (or a second thin film transistor, a second switching element). The transistors <NUM> and <NUM> may include active layers <NUM> and <NUM>, gate electrodes <NUM> and <NUM>, source electrodes <NUM> and <NUM>, and drain electrodes <NUM> and <NUM>, respectively. The light-emitting element layer <NUM> may include a first electrode <NUM>, a second electrode <NUM>, and a light-emitting element <NUM>. The transistors <NUM> and <NUM>, the first electrode <NUM>, the second electrode <NUM>, and the light-emitting element <NUM> described above may constitute a pixel circuit. A specific example of the pixel circuit is illustrated in <FIG>.

<FIG> is a circuit diagram of one pixel of a light-emitting device according to an embodiment.

Referring to <FIG>, a pixel circuit may include a first transistor TR1 (<NUM> in <FIG>), a second transistor TR2 (<NUM> in <FIG>), a capacitor Cst, and a light-emitting diode (LED).

The first transistor TR1 may be a driving transistor, and the second transistor TR2 may be a switching transistor. <FIG> illustrates a case in which both of the first transistor TR1 and the second transistor TR2 are p-channel metal-oxide-semiconductor (PMOS) transistors, but any one or both of the first transistor TR1 and the second transistor TR2 may be n-channel metal-oxide-semiconductor (NMOS) transistors.

A source electrode (<NUM> in <FIG>) of the first transistor TR1 is connected to a first power line ELVDDL and a drain electrode (<NUM> in <FIG>) is connected to an anode electrode (the first electrode <NUM> in <FIG>) of an organic light-emitting diode (OLED). A source electrode (<NUM> in <FIG>) of the second transistor TR2 is connected to a data line DL, and a drain electrode (<NUM> in <FIG>) is connected to a gate electrode (<NUM> in <FIG>) of the first transistor TR1. The capacitor Cst is connected between the gate electrode and the source electrode of the first transistor TR1. A cathode electrode (the second electrode <NUM> in <FIG>) of the LED receives a second power voltage ELVSS. The second power voltage ELVSS may be a voltage lower than a first power voltage ELVDD provided from the first power line ELVDDL.

The second transistor TR2 may output a data signal applied to the data line DL in response to a scan signal applied to a scan line SL. The capacitor Cst may charge a voltage corresponding to the data signal received from the second transistor TR2. The first transistor TR1 may control a driving current flowing through the LED to correspond to an amount of charge stored in the capacitor Cst. An equivalent circuit diagram of <FIG> is only one embodiment, and the pixel circuit may include a larger number (e.g., seven) of transistors and capacitors.

Referring to <FIG> again, the circuit board <NUM> may include the substrate <NUM>, a buffer layer <NUM>, a semiconductor layer, a first insulating layer <NUM>, a first conductive layer, a second insulating layer <NUM>, a second conductive layer, a third insulating layer <NUM>, a third conductive layer, and a fourth insulating layer <NUM>.

The substrate <NUM> may be an insulating substrate. The substrate <NUM> may be made of an insulating material such as glass, quartz, a polymer resin, or the like. The polymer material may include polyethersulphone (PES), polyacrylate (PA), polyarylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyallylate, polyimide (PI), polycarbonate (PC), cellulose triacetate (CAT), cellulose acetate propionate (CAP), or a combination thereof. The substrate <NUM> may be a rigid substrate but may be a flexible substrate which is capable of being bent, folded, rolled, or the like.

The buffer layer <NUM> may be disposed on the substrate <NUM>. The buffer layer <NUM> may prevent the diffusion of impurity ions, prevent the penetration of moisture or external air, and perform a surface planarization function. The buffer layer <NUM> may include silicon nitride, silicon oxide, silicon oxynitride, or the like.

The semiconductor layer may be disposed on the buffer layer <NUM>. The semiconductor layer may include a first active layer <NUM> of the first transistor <NUM>, a second active layer <NUM> of the second transistor <NUM>, and an auxiliary layer <NUM>. The semiconductor layer may include polycrystalline silicon, single crystalline silicon, oxide semiconductor, or the like.

The first insulating layer <NUM> may be disposed on the semiconductor layer. The first insulating layer <NUM> may cover the semiconductor layer. The first insulating layer <NUM> may function as a gate insulating film of a transistor. The first insulating layer <NUM> may include silicon oxide, silicon nitride, silicon oxynitride, aluminium oxide, tantalum oxide, hafnium oxide, zirconium oxide, titanium oxide, or the like. The above materials may be used alone or in combination with each other.

The first conductive layer may be disposed on the first insulating layer <NUM>. The first conductive layer may include a first gate electrode <NUM> disposed on the first active layer <NUM> of the first transistor <NUM> with the first insulating layer <NUM> interposed therebetween, a second gate electrode <NUM> disposed on the second active layer <NUM> of the second transistor <NUM>, and a power line <NUM> disposed on the auxiliary layer <NUM>. The first conductive layer may include one or more metals selected from among molybdenum (Mo), aluminium (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu). The first conductive layer may be a single film or a multilayered film.

The second insulating layer <NUM> may be disposed on the first conductive layer. The second insulating layer <NUM> may be made of an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, hafnium oxide, aluminium oxide, titanium oxide, tantalum oxide, zinc oxide, or the like.

The second conductive layer may be disposed on the second insulating layer <NUM>. The second conductive layer may include a capacitor electrode <NUM> disposed on the first gate electrode <NUM> with the second insulating layer interposed therebetween. The capacitor electrode <NUM> may form a storage capacitor (e.g., a capacitor that stores or maintains an electrical signal) together with the first gate electrode <NUM>.

The second conductive layer, similar to the first conductive layer, may include one or more metals selected from among molybdenum (Mo), aluminium (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu).

The third insulating layer <NUM> may be disposed on the second conductive layer. The third insulating layer <NUM> may be an interlayer insulating film. Further, the third insulating layer <NUM> may perform a surface planarization function. The third insulating layer <NUM> may include an organic insulating material such as a polyacrylate resin, an epoxy resin, a phenolic resin, a polyamide resin, a polyimide resin, an unsaturated polyester resin, a polyphenylene ether resin, a polyphenylene sulfide resin, benzocyclobutene (BCB), or the like.

The third conductive layer may be disposed on the third insulating layer <NUM>. The third conductive layer may include a first drain electrode <NUM> and a first source electrode <NUM> of the first transistor <NUM>, a second drain electrode <NUM> and a second source electrode <NUM> of the second transistor <NUM>, and the power electrode <NUM> disposed above the power line <NUM>.

Each of the first source electrode <NUM> and the first drain electrode <NUM> may be electrically connected to the first active layer <NUM> through a first contact hole <NUM> passing through the third insulating layer <NUM>, the second insulating layer <NUM>, and the first insulating layer <NUM>. Each of the second source electrode <NUM> and the second drain electrode <NUM> may be electrically connected to the second active layer <NUM> through a second contact hole <NUM> passing through the third insulating layer <NUM>, the second insulating layer <NUM>, and the first insulating layer <NUM>. The power electrode <NUM> may be electrically connected to the power line <NUM> through a third contact hole <NUM> passing through the third insulating layer <NUM> and the second insulating layer <NUM>.

The third conductive layer may include one or more metals selected from among aluminium (Al), molybdenum (Mo), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu). The third conductive layer may be a single film or a multilayered film. For example, the third conductive layer may be formed in a stacked structure of Ti/Al/Ti, Mo/Al/Mo, Mo/AlGe/Mo, Ti/Cu, or the like.

The fourth insulating layer <NUM> may be disposed on the third conductive layer. The fourth insulating layer <NUM> may be made of an organic insulating material such as a polyacrylate resin, an epoxy resin, a phenolic resin, a polyamide resin, a polyimide resin, an unsaturated polyester resin, a polyphenylene ether resin, a polyphenylene sulfide resin, BCB, or the like. A surface of the fourth insulating layer <NUM> may be flat.

Hereinafter, the light-emitting element layer <NUM> will be described.

The first electrode <NUM> and the second electrode <NUM> may be disposed on the fourth insulating layer <NUM>. The first electrode <NUM> may be electrically connected to the first drain electrode <NUM> of the first transistor <NUM> through a fourth contact hole 319_1 passing through the fourth insulating layer <NUM>. The second electrode <NUM> may be disposed to be spaced apart from the first electrode <NUM> and may be electrically connected to the power electrode <NUM> through a fifth contact hole 319_2 passing through the fourth insulating layer <NUM>.

The first electrode <NUM> and the second electrode <NUM> may include one or more metals selected from among aluminium (Al), molybdenum (Mo), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu). The first electrode <NUM> is a multilayered film and the second electrode <NUM> may be a single film or a multilayered film. For example, the first electrode <NUM> and the second electrode <NUM> may be formed in a stacked structure of Ti/Al/Ti, Mo/Al/Mo, Mo/AlGe/Mo, Ti/Cu, or the like.

In an embodiment, the first electrode <NUM> and the second electrode <NUM> may include a reflective material (or a material having high reflectivity) having a reflective property of reflecting light. Here, the reflective material may include at least one selected from the group consisting of silver (Ag), magnesium (Mg), chromium (Cr), gold (Au), platinum (Pt), nickel (Ni), copper (Cu), tungsten (W), aluminium (Al), aluminium-lithium (Al-Li), magnesium-indium (Mg-In), and magnesium-silver (Mg-Ag). In this case, the first electrode <NUM> and the second electrode <NUM> may function as reflective walls that reflect light emitted from a side surface of the light-emitting element <NUM>.

In an embodiment, at least one of a thickness of the first electrode <NUM> and a thickness of the second electrode <NUM> may be greater than a thickness of the light-emitting element <NUM>.

The thickness of the first electrode <NUM> and the thickness of the second electrode <NUM> may be determined by positions in a thickness direction of the light-emitting element <NUM>, an angle at which light is emitted from the light-emitting element <NUM>, separation distances from the light-emitting element <NUM>, or the like, but the thickness of the first electrode <NUM> and the thickness of the second electrode <NUM> may be substantially greater than the thickness (e.g., <NUM>,<NUM>Å) of the light-emitting element <NUM>. For example, the thickness of the first electrode <NUM> may be <NUM>,<NUM>Å or more, <NUM>,<NUM>Å or more, or <NUM>,<NUM>Å or more, or may be <NUM>,<NUM>Å. Furthermore, the thickness of the first electrode <NUM> and the thickness of the second electrode <NUM> may be greater than a length (or a maximum length, for example, <NUM>,<NUM>Å) of the light-emitting element <NUM>. For example, the thickness of the first electrode <NUM> may be <NUM>,<NUM>Å or more. The thickness of the first electrode <NUM> and the thickness of the second electrode <NUM> may be smaller than <NUM>,<NUM>Å.

According to the invention, the first electrode <NUM> has inclined sidewalls, and the second electrode <NUM> may have inclined sidewalls or a tapered cross-sectional shape.

An inner sidewall 332_S1 (or a first inclined surface) of the first electrode <NUM> adjacent to the light-emitting element <NUM> forms an acute angle with the fourth insulating layer <NUM>. Similarly, an outer sidewall 342_S1 (or an inclined surface) of the second electrode <NUM> adjacent to the light-emitting element <NUM> may form an acute angle with the fourth insulating layer <NUM>. That is, the inner sidewall 332_S1 of the first electrode <NUM> which is positioned adjacent to the light-emitting element <NUM> is formed to be inclined, and the outer sidewall 342_S1 of the second electrode <NUM> which is positioned adjacent to the light-emitting element <NUM> may be formed to be inclined. In this case, the light emitted from the side surface of the light-emitting element <NUM> may be substantially reflected upward by the inner sidewall 332_S1 of the first electrode <NUM> and the outer sidewall 342_S1 of the second electrode <NUM>. Further, an outer sidewall 332_S2 (or a second inclined surface) of the first electrode <NUM> may also form an acute angle with the fourth insulating layer <NUM> or may be formed to be inclined.

In some embodiments, a first inclination angle Θ1 (or a first taper angle) of the inner sidewall 332_S1 (or the first inclined surface) of the first electrode <NUM> may be <NUM> degrees or less, in a range of <NUM> degrees to <NUM> degrees, or in a range of <NUM> degrees to <NUM> degrees. In this case, the light emitted from the side surface of the light-emitting element <NUM> may be substantially reflected upward in a region occupied by the first pixel PX1 illustrated in <FIG>. Similarly, an inclination angle of the outer sidewall 342_S1 of the second electrode <NUM> may be identical or similar to the first inclination angle Θ1. As will be described below, the inner sidewall 332_S1 of the first electrode <NUM> and the outer sidewall 342_S1 of the second electrode <NUM> may be formed through the same process (e.g., a patterning process, a masking process, or an etching process), and thus the first inclined surface of the first electrode <NUM> may be substantially the same as the inclined surface of the second electrode <NUM>.

In an embodiment, the first inclination angle Θ1 of the inner sidewall 332_S1 of the first electrode <NUM> may be different from a second inclination angle Θ2 (or a second taper angle) of the outer sidewall 332_S2 of the first electrode <NUM>. Here, the outer sidewall 332_S2 of the first electrode <NUM> may be a side surface formed along an outer edge of the first electrode <NUM>, may be spaced apart from the second electrode <NUM>, and may be adjacent to or may face a first electrode of another pixel (e.g., the second pixel PX2).

As will be described with reference to <FIG>, the outer sidewall 332_S2 of the first electrode <NUM> may be formed through a process (or at a different time point) different from a process (or a time point) in which the inner sidewall 332_S1 of the first electrode <NUM> is formed, and the outer sidewall 332_S2 of the first electrode <NUM> does not need to function as a reflective wall that reflects light in a specific direction. Accordingly, the second inclination angle Θ2 of the outer sidewall 332_S2 of the first electrode <NUM> may be different from the first inclination angle Θ1 of the inner sidewall 332_S1 of the first electrode <NUM>. For example, the second inclination angle Θ2 of the outer sidewall 332_S2 of the first electrode <NUM> may be greater than the first inclination angle Θ1 of the inner sidewall 332_S1 of the first electrode <NUM>.

However, the above configuration is exemplary and the present invention is not limited thereto. For example, the second inclination angle Θ2 of the outer sidewall 332_S2 of the first electrode <NUM> may be smaller than the first inclination angle Θ1 of the inner sidewall 332_S1 of the first electrode <NUM>, and the second inclination angle Θ2 of the outer sidewall 332_S2 of the first electrode <NUM> may be identical to the first inclination angle Θ1 of the inner sidewall 332_S1 of the first electrode <NUM>.

According to the invention, the first electrode <NUM> and the second electrode <NUM> may include first metal bonding layers <NUM> and <NUM>, metal conductive layers <NUM> and <NUM>, and second metal bonding layers <NUM> and <NUM>, respectively. Based on the first electrode <NUM>, the first metal bonding layer <NUM> is disposed on the circuit board <NUM> (or the fourth insulating layer <NUM>) and may have low contact resistance with respect to a lower conductive layer (e.g., the first drain electrode <NUM>, the power electrode <NUM>). The metal conductive layer <NUM> is disposed on the first metal bonding layer <NUM> and may have relatively high electrical conductivity (or conductivity). The second metal bonding layer <NUM> is disposed on the metal conductive layer <NUM> and may have relatively high bonding force with a fifth insulating layer <NUM> to be described below.

The metal conductive layer <NUM> has a thickness which is greater than a thickness of the first metal bonding layer <NUM> and greater than a thickness of the second metal bonding layer <NUM>. The inclined inner sidewall 332_S1 and the inclined outer sidewall 332_S2 (or the first inclined surface and the second inclined surface) of the first electrode <NUM> are formed on the metal conductive layer <NUM>. Similarly, the inclined outer sidewall 342_S1 of the second electrode <NUM> may be formed on the metal conductive layer <NUM>.

As the metal conductive layer <NUM> has a relatively large thickness, the first electrode <NUM> may be formed relatively thick, and thus a resistance value of the first electrode <NUM> may be relatively small. Therefore, a drop (e.g., IR drop) of an electrical signal (e.g., a data signal corresponding to an image or a power source V used for an arrangement of the light-emitting elements <NUM> to be described below) due to the first electrode <NUM> may be reduced, and alignment efficiency of the light-emitting elements <NUM> may be improved.

Referring to <FIG> again, the fifth insulating layer <NUM> may be disposed on some regions of the first electrode <NUM> and the second electrode <NUM>. The fifth insulating layer <NUM> may be disposed in a space between the first electrode <NUM> and the second electrode <NUM>. For example, the fifth insulating layer <NUM> may include a first insulating pattern <NUM>, a second insulating pattern <NUM>, and a third insulating pattern <NUM>.

The first insulating pattern <NUM> may form closed loops along peripheries (or the edges of the second electrodes <NUM>) of the holes HOL1, HOL2, and HOL3 of the first electrode <NUM> in a top view, and may have, for example, a ring shape in a top view. The second insulating pattern <NUM> may be disposed on the first electrode <NUM> and the third insulating pattern <NUM> may be disposed on the second electrode <NUM>.

The first insulating pattern <NUM> may be disposed between the light-emitting element <NUM> and the fourth insulating layer <NUM>. A lower surface of the first insulating pattern <NUM> may be in contact with the fourth insulating layer <NUM> and the light-emitting element <NUM> may be disposed on an upper surface of the first insulating pattern <NUM>. The first insulating pattern <NUM> may be in contact with the first electrode <NUM> and the second electrode <NUM> at both side surfaces, may physically separate the first electrode <NUM> from the second electrode <NUM>, and may prevent the first electrode <NUM> and the second electrode <NUM> from being in direct contact with each other. That is, the first insulating pattern <NUM> may prevent the first electrode <NUM> and the second electrode <NUM> from being directly electrically connected to each other on the same plane.

The fifth insulating layer <NUM> (or the first insulating pattern <NUM>) may overlap some regions of the first electrode <NUM> and the second electrode <NUM>, for example, portions of the inclined surfaces of the first electrode <NUM> and the second electrode <NUM>, which are formed in a direction in which the first electrode <NUM> and the second electrode <NUM> face each other. For example, both end portions of the first insulating pattern <NUM> may cover the inclined surfaces formed in the direction in which the first electrode <NUM> and the second electrode <NUM> face each other. The first insulating pattern <NUM> may protect the regions overlapping the first electrode <NUM> and the second electrode <NUM> and, at the same time, may electrically insulate the first electrode <NUM> from the second electrode <NUM>. Further, the first semiconductor layer <NUM> and the second semiconductor layer <NUM> of the light-emitting element <NUM> to be described below may be prevented from being in direct contact with other base materials so that the light-emitting element <NUM> may be prevented from being damaged.

In <FIG>, the first insulating pattern <NUM> is illustrated as extending longer than the light-emitting element <NUM>, but the present invention is not limited thereto. For example, the first insulating pattern <NUM> may have a length similar to a length of the light-emitting element <NUM>, and both side surfaces of the first insulating pattern <NUM> may be aligned with both side surfaces of the light-emitting element <NUM>.

The first electrode <NUM> and the second electrode <NUM> may be disposed to be spaced a predetermined interval from each other, and the interval may be smaller than or equal to the length of the light-emitting element <NUM>. In this case, electrical contact between the first and second electrodes <NUM> and <NUM> and the light-emitting element <NUM> may be made smoothly.

Pixel walls <NUM> and <NUM> may be formed on the fifth insulating layer <NUM>. The pixel walls <NUM> and <NUM> may define boundaries between the pixels PX1, PX2, and PX3. Further, the pixel walls <NUM> and <NUM> may define a region in which a light-emitting element solution S (i.e., a solution including the light-emitting element <NUM>), which will be described in <FIG>, is disposed using an inkjet printing method or the like.

A first pixel wall <NUM> may be disposed on the second insulating pattern <NUM>, and a second pixel wall <NUM> may be disposed on the third insulating pattern <NUM>. The second pixel wall <NUM> may be omitted. In <FIG>, the first pixel wall <NUM> is illustrated as being disposed to overlap the second insulating pattern <NUM>, but the present invention is not limited thereto. For example, the first pixel wall <NUM> may be disposed to overlap an outer side surface of the first electrode <NUM>.

The light-emitting element <NUM> is disposed between the first electrode <NUM> and the second electrode <NUM>. The light-emitting element <NUM> may emit light having a different color according to a material of an active material layer. When different types of light-emitting elements are arranged in the pixels PX1, PX2, and PX3, the pixels PX1, PX2, and PX3 may emit pieces of light having different colors. For example, the light-emitting element <NUM> emits light in a blue, green, or red wavelength band so that the pixels PX1, PX2, and PX3 may emit blue, green, and red light, respectively. However, the present invention is not limited thereto. In some cases, the light-emitting elements <NUM> may all emit light in the same color wavelength band so that the pixels PX1, PX2, and PX3 may be implemented to emit light having the same color (e.g., blue). Further, light-emitting elements that emit pieces of light having different color wavelength bands may be disposed in one pixel (e.g., the first pixel PX1) to emit the pieces of light having different colors (e.g., white).

The light-emitting element <NUM> may be an LED. The light-emitting element <NUM> may have a nanostructure having a size of a nano unit. The light-emitting element <NUM> may be an inorganic light-emitting diode made of an inorganic material. When the light-emitting element <NUM> is an inorganic light-emitting diode, a light-emitting material having an inorganic crystalline structure may be disposed between two electrodes facing each other, and when an electric field is formed in a specific direction on the light-emitting material, the inorganic light-emitting diodes may be arranged between the two electrodes having a specific polarity. An arrangement of the light-emitting elements <NUM> will be described below with reference to <FIG>.

A sixth insulating layer <NUM> may be disposed on the light-emitting element <NUM> to protect the light-emitting element <NUM> and fix the light-emitting element <NUM> between the first electrode <NUM> and the second electrode <NUM>. The sixth insulating layer <NUM> may also be disposed on an outer surface of the light-emitting element <NUM> to fix the light-emitting element <NUM>. The sixth insulating layer <NUM> may be disposed in some regions of the outer surface of the light-emitting element <NUM> so that both side surfaces of the light-emitting element <NUM> may be exposed.

The sixth insulating layer <NUM> may include an insulating inorganic material. When the sixth insulating layer <NUM> is formed through a masking process, a defect (a seam) of an inorganic material crystal may be generated in the upper surface and an outer circumferential surface of the light-emitting element <NUM> and in a region adjacent to the light-emitting element <NUM>. When a defect is generated in a region in which the light-emitting element <NUM> and the inorganic material layer are in contact with each other, the inorganic material layer may be excessively etched due to the defect during a subsequent masking process or, in some cases, the materials that are in contact with each other may be separated. Further, a gap may be formed between the light-emitting element <NUM> and the fourth insulating layer <NUM>. Furthermore, when the inorganic material layer is deposited, the sixth insulating layer <NUM> may be non-uniformly formed on the light-emitting element <NUM> due to low step-coverage. Further, even in the case in which a first contact electrode <NUM> and a second contact electrode <NUM> are formed, when the step-coverage is low, the contact electrode material may be cut and the light-emitting element <NUM> may be electrically disconnected.

Accordingly, a seventh insulating layer <NUM> may be disposed on the sixth insulating layer <NUM>. A cross section of the seventh insulating layer <NUM> may be disposed on a cross section of the sixth insulating layer <NUM>, and the seventh insulating layer <NUM> may be disposed to cover at least a portion of an outer surface of the sixth insulating layer <NUM>.

The seventh insulating layer <NUM> may fill a defect (a seam) that may be formed in the inorganic material layer such as the sixth insulating layer <NUM> or a gap that may be formed below the light-emitting element <NUM>. Accordingly, the low step-coverage of the sixth insulating layer <NUM> may be eliminated and the disconnection of the contact electrode material may be prevented. Further, the sixth insulating layer <NUM> may be planarized by the seventh insulating layer <NUM>. When an upper surface of the sixth insulating layer <NUM> is planarized by the seventh insulating layer <NUM>, a subsequent process of forming the first contact electrode <NUM> and the second contact electrode <NUM> may be performed relatively smoothly.

A length of the seventh insulating layer <NUM> may be smaller than a length of the light-emitting element <NUM> and, in this case, the light-emitting element <NUM> and the seventh insulating layer <NUM> may be stacked in a stepped manner.

The first contact electrode <NUM> and the second contact electrode <NUM> may be disposed on the seventh insulating layer <NUM>. The first contact electrode <NUM> may be disposed on the first electrode <NUM> and may overlap at least a portion of the seventh insulating layer <NUM>. The second contact electrode <NUM> may be disposed on the second electrode <NUM>, may be disposed to be spaced apart from the first contact electrode <NUM>, and may be in contact with at least a portion of the seventh insulating layer <NUM>.

The first contact electrode <NUM> and the second contact electrode <NUM> may be electrically connected to the first electrode <NUM> and the second electrode <NUM> which are partially exposed by the fifth insulating layer <NUM> (or the second insulating pattern <NUM>, the third insulating pattern <NUM>), respectively. The first contact electrode <NUM> and the second contact electrode <NUM> may be disposed on upper surfaces (i.e., upper surfaces exposed by the second insulating pattern <NUM> and the third insulating pattern <NUM>) of the first electrode <NUM> and the second electrode <NUM>, respectively. The first contact electrode <NUM> and the second contact electrode <NUM> may be in contact with the upper surfaces (and/or the side surface, the inclined surface) of the first electrode <NUM> and the second electrode <NUM>, respectively. The first contact electrode <NUM> and the second contact electrode <NUM> may be in contact with the first semiconductor layer <NUM> and the second semiconductor layer <NUM> of the light-emitting element <NUM>, respectively. Accordingly, the first contact electrode <NUM> and the second contact electrode <NUM> may transmit signals applied to the first electrode <NUM> and the second electrode <NUM> to the light-emitting element <NUM>, respectively.

The first contact electrode <NUM> may be disposed on the first electrode <NUM> to cover the first electrode <NUM>, and a lower surface of the first contact electrode <NUM> may be in partial contact with the light-emitting element <NUM> and the seventh insulating layer <NUM>. One end portion of the first contact electrode <NUM> in a direction in which the second electrode <NUM> is disposed may be disposed on the seventh insulating layer <NUM>. The second contact electrode <NUM> may be disposed on the second electrode <NUM> to cover the second electrode <NUM>, and a lower surface of the second contact electrode <NUM> may be in partial contact with the light-emitting element <NUM>, the seventh insulating layer <NUM>, and an eighth insulating layer <NUM>. One end portion of the second contact electrode <NUM> in a direction in which the first electrode <NUM> is disposed may be disposed on the eighth insulating layer <NUM>.

The first contact electrode <NUM> and the second contact electrode <NUM> may be disposed on the seventh insulating layer <NUM> or the eighth insulating layer <NUM> to be spaced apart from each other. That is, the first contact electrode <NUM> and the second contact electrode <NUM> may be in contact with the light-emitting element <NUM> together with the seventh insulating layer <NUM> or the eighth insulating layer <NUM>, but may not be connected by being spaced apart from each other on the seventh insulating layer <NUM>. The first contact electrode <NUM> and the second contact electrode <NUM> may be physically spaced apart from each other and thus different voltages may be applied thereto. For example, an electrical signal (e.g., a driving voltage), which is applied from the first transistor <NUM> to the first electrode <NUM>, may be applied to the first contact electrode <NUM> connected to the first electrode <NUM> through the fourth contact hole 319_1 passing through the fourth insulating layer <NUM>, and a power voltage, which is applied from the power line <NUM> and the power electrode <NUM> to the second electrode <NUM>, may be applied to the second contact electrode <NUM> connected to the second electrode <NUM> through the fifth contact hole 319_2 passing through the fourth insulating layer <NUM>. However, the present invention is not limited thereto.

The first contact electrode <NUM> and the second contact electrode <NUM> may include a conductive material. For example, the first contact electrode <NUM> and the second contact electrode <NUM> may include indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), aluminium (Al), or the like. However, the present invention is not limited thereto.

The first contact electrode <NUM> and the second contact electrode <NUM> may be disposed on the first electrode <NUM> and the second electrode <NUM> in substantially the same pattern so as to be in contact with the first electrode <NUM> and the second electrode <NUM>.

The eighth insulating layer <NUM> may be disposed above the first contact electrode <NUM>, may physically separate the first contact electrode <NUM> from the second contact electrode <NUM>, and may prevent the first contact electrode <NUM> and the second contact electrode <NUM> from being in direct contact with each other. The eighth insulating layer <NUM> may be disposed to cover the first contact electrode <NUM> and may be disposed so as not to overlap a region of the light-emitting element <NUM> so that the light-emitting element <NUM> may be connected to the second contact electrode <NUM>. On an upper surface of the seventh insulating layer <NUM>, the eighth insulating layer <NUM> may be in partial contact with the first contact electrode <NUM> and the seventh insulating layer <NUM>. The eighth insulating layer <NUM> may be disposed on the upper surface of the seventh insulating layer <NUM> to cover one end portion of the first contact electrode <NUM>. Accordingly, the eighth insulating layer <NUM> may protect the first contact electrode <NUM> and, at the same time, may prevent the first contact electrode <NUM> from being in direct contact with the second contact electrode <NUM>.

One end portion of the eighth insulating layer <NUM> in the direction in which the second electrode <NUM> is disposed may be disposed to cover the seventh insulating layer <NUM> and may be aligned with one side surface of the sixth insulating layer <NUM>.

The eighth insulating layer <NUM> may be omitted. Accordingly, the first contact electrode <NUM> and the second contact electrode <NUM> may be disposed to be substantially coplanar, and the first contact electrode <NUM> and the second contact electrode <NUM> may be physically separated from each other by a passivation layer <NUM> to be described below and may not be directly connected to each other.

The passivation layer <NUM> may be formed above the eighth insulating layer <NUM> and the second contact electrode <NUM> and may function to protect the members disposed on the fourth insulating layer <NUM> from an external environment. When the first contact electrode <NUM> and the second contact electrode <NUM> are exposed, since a disconnection problem of the contact electrode material may occur due to damage to the electrodes, the first contact electrode <NUM> and the second contact electrode <NUM> may be covered with the passivation layer <NUM>. That is, the passivation layer <NUM> may be disposed to cover the first electrode <NUM>, the second electrode <NUM>, the light-emitting element <NUM>, and the like. Further, when the eighth insulating layer <NUM> is omitted, the passivation layer <NUM> may be formed above the first contact electrode <NUM> and the second contact electrode <NUM>. In this case, the passivation layer <NUM> may electrically insulate the first contact electrode <NUM> from the second contact electrode <NUM>.

In an embodiment, each of the fifth insulating layer <NUM>, the sixth insulating layer <NUM>, the eighth insulating layer <NUM>, and the passivation layer <NUM> may include an inorganic insulating material. For example, the fifth insulating layer <NUM>, the sixth insulating layer <NUM>, the eighth insulating layer <NUM>, and the passivation layer <NUM> may include a material such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), aluminium oxide (Al<NUM>O<NUM>), aluminium nitride (AlN), or the like. The fifth insulating layer <NUM>, the sixth insulating layer <NUM>, the eighth insulating layer <NUM>, and the passivation layer <NUM> may be made of the same material but may be made of different materials. In addition, various materials that impart insulation may be applied to the fifth insulating layer <NUM>, the sixth insulating layer <NUM>, the eighth insulating layer <NUM>, and the passivation layer <NUM>.

Meanwhile, the fifth insulating layer <NUM>, the eighth insulating layer <NUM>, and the passivation layer <NUM> may further include an organic insulating material like the seventh insulating layer <NUM>. However, the present invention is not limited thereto. Any material may be used as the organic insulating material included in the seventh insulating layer <NUM> without any particular limitation as long as the material is within a range that does not affect the characteristics of the light-emitting element solution S. For example, the organic insulating material may include at least one selected from the group consisting of an epoxy resin, a cardo resin, a polyimide resin, an acrylic resin, a siloxane resin, and a silsesquioxane resin, but the present invention is not limited thereto.

As described with reference to <FIG>, the light-emitting device <NUM> includes the first electrode <NUM> and the second electrode <NUM>, which are made of a reflective material and have thick and inclined surfaces, and includes the light-emitting element <NUM> disposed between the first electrode <NUM> and the second electrode <NUM>. That is, the first electrode <NUM> and the second electrode <NUM> may be formed as an integrated reflective electrode instead of including separate walls, electrodes, reflective electrodes and the like, and thus a manufacturing process of the light-emitting device <NUM> may be more simplified.

Further, the first electrode <NUM> and the second electrode <NUM> may be formed to be relatively thick so that resistance values thereof may be relatively reduced. Accordingly, the drop of the electrical signal (e.g., the power for aligning the light-emitting elements <NUM> or the data signal for displaying the image) applied to the first electrode <NUM> and the second electrode <NUM> may be prevented and the light emission efficiency (or the alignment efficiency of the light-emitting element <NUM>) and display quality of the light-emitting device <NUM> may be improved.

<FIG> is a view illustrating an example of the light-emitting element included in the light-emitting device of <FIG>.

Referring to <FIG>, a light-emitting element <NUM> may include semiconductor layers <NUM> and <NUM> and an active material layer <NUM> disposed between the semiconductor layers <NUM> and <NUM>. Further, the light-emitting element <NUM> may further include an insulating material layer <NUM>. Electrical signals applied from the first electrode <NUM> and the second electrode <NUM> may be transmitted to the active material layer <NUM> through the semiconductor layers <NUM> and <NUM> to emit light.

A first semiconductor layer <NUM> may be an N-type semiconductor layer. For example, when the light-emitting element <NUM> emits light in a blue wavelength band, the first semiconductor layer <NUM> may be a semiconductor material having a chemical formula of InxAlyGa<NUM>-x-yN (<NUM>≤x≤<NUM>, <NUM>≤y≤<NUM>, <NUM>≤x+y≤<NUM>). For example, the first semiconductor layer <NUM> may be any one or more of N-type doped InAlGaN, GaN, AlGaN, InGaN, AlN, and InN. The first semiconductor layer <NUM> may be doped with a first conductive dopant, and the first conductive dopant may be, for example, Si, Ge, Sn, or the like. The first semiconductor layer <NUM> may have a length in a range of <NUM> to <NUM>, but the present invention is not limited thereto.

A second semiconductor layer <NUM> may be a P-type semiconductor layer. For example, when the light-emitting element <NUM> emits light in a blue wavelength band, the second semiconductor layer <NUM> may be a semiconductor material having a chemical formula of InxAlyGa<NUM>-x-yN (<NUM>≤x≤<NUM>, <NUM>≤y≤<NUM>, <NUM>≤x+y≤<NUM>). For example, the second semiconductor layer <NUM> may be any one or more of P-type doped InAlGaN, GaN, AlGaN, InGaN, AlN, and InN. The second semiconductor layer <NUM> may be doped with a second conductive dopant and the second conductive dopant may be, for example, Mg, Zn, Ca, Se, Ba, or the like. The second semiconductor layer <NUM> may have a length in a range of <NUM> to <NUM>, but the present invention is not limited thereto.

The active material layer <NUM> may be disposed between the first semiconductor layer <NUM> and the second semiconductor layer <NUM> and may include a material having a single or multiple quantum well structure. However, the present invention is not limited thereto, and the active material layer <NUM> may have a structure in which a semiconductor material having a high band gap energy and a semiconductor material having a low band gap energy are alternately stacked.

The active material layer <NUM> may emit light by combination of an electron-hole pair according to the electrical signals applied through the first semiconductor layer <NUM> and the second semiconductor layer <NUM>. For example, when the active material layer <NUM> emits light in a blue wavelength band, the active material layer <NUM> may include a material such as AlGaN, AlInGaN, or the like, and may include other group III to group V semiconductor materials according to the wavelength band of the emitted light. Accordingly, the light emitted from the active material layer <NUM> is not limited to the light in the blue wavelength band and, in some cases, light in a red or green wavelength band may be emitted. The active material layer <NUM> may have a length in a range of <NUM> to <NUM>, but the present invention is not limited thereto.

The light emitted from the active material layer <NUM> may be emitted not only to an outer surface of the light-emitting element <NUM> in a longitudinal direction, but also to both side surfaces. That is, the light emitted from the active material layer <NUM> is not limited in directionality to one direction.

The insulating material layer <NUM> may be formed at the outer side of the light-emitting element <NUM> to protect the light-emitting element <NUM>. For example, the insulating material layer <NUM> may be formed to surround the side surface of the light-emitting element <NUM> and may not be formed on both end portions of the light-emitting element <NUM> in the longitudinal direction, for example, both end portions of the first semiconductor layer <NUM> and the second semiconductor layer <NUM>. However, the present invention is not limited thereto. The insulating material layer <NUM> may include material having insulating properties, for example, silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), aluminium nitride (AlN), aluminium oxide (Al<NUM>O<NUM>), and the like. Accordingly, an electrical short that may occur when the active material layer <NUM> is brought into direct contact with the first electrode <NUM> or the second electrode <NUM> may be prevented. Further, since the insulating material layer <NUM> protects the outer surface of the light-emitting element <NUM> as well as the active material layer <NUM>, a decrease in light emission efficiency may be prevented.

The insulating material layer <NUM> may have a thickness in a range of <NUM> to <NUM>, but the present invention is not limited thereto.

The light-emitting element <NUM> may have a cylindrical shape. However, the shape of the light-emitting element <NUM> is not limited thereto, and the light-emitting element <NUM> may have various shapes such as a cubic shape, a rectangular parallelepiped shape, a hexagonal column shape, and the like. The light-emitting element <NUM> may have a length in a range of <NUM> to <NUM> or a range of <NUM> to <NUM>, and preferably, may have a length of about <NUM>. Further, the light-emitting element <NUM> may have a diameter in a range of <NUM> to <NUM>, and preferably, may have a thickness of about <NUM>.

In some embodiments, the light-emitting element <NUM> may further include an electrode layer on at least one of both side surfaces on which the first semiconductor layer <NUM> and the second semiconductor layer <NUM> are disposed. In this case, the insulating material layer <NUM> may be formed to extend in a longitudinal direction so as to cover the electrode layer. However, the present invention is not limited thereto, and the insulating material layer <NUM> may cover only the first semiconductor layer <NUM>, the active material layer <NUM>, and the second semiconductor layer <NUM> or may cover only a portion of an outer surface of the electrode layer so that some portions of the outer surface of the electrode layer may be exposed.

The electrode layer may be an ohmic contact electrode. However, the present invention is not limited thereto, and the electrode layer may be a Schottky contact electrode. The electrode layer may include a conductive metal. For example, the electrode layer may include at least one of aluminium (Al), titanium (Ti), indium (In), gold (Au), and silver(Ag).

<FIG> are views illustrating a method of manufacturing the light-emitting device of <FIG>.

First, referring to <FIG>, <FIG>, and <FIG>, a circuit board <NUM> is provided. In <FIG>, only a fourth insulating layer <NUM> of the circuit board <NUM> is illustrated but, for convenience of description, a substrate <NUM>, transistors <NUM> and <NUM>, a power line <NUM>, and the like are omitted, and the configuration of the circuit board <NUM> described with reference to <FIG> may be applied to a configuration of the circuit board <NUM> in <FIG> without change.

Subsequently, an unseparated mother electrode <NUM> is formed on the circuit board <NUM>. The mother electrode <NUM> is an entire unseparated electrode formed over an entirety of one surface of the circuit board <NUM> and is an electrode which will be separated by patterning thereafter to become a plurality of first electrodes and a plurality of second electrodes. A plurality of fourth contact holes (319_1 in <FIG>) and a plurality of fifth contact holes (319_2 in <FIG>) are already formed in the circuit board <NUM> so that the mother electrode <NUM> may be electrically connected to a first drain electrode <NUM> of a first transistor <NUM> and a power electrode <NUM> through the fourth contact holes 319_1 and the fifth contact holes 319_2.

The mother electrode <NUM> includes a first metal bonding layer <NUM>, a metal conductive layer <NUM>, and a second metal bonding layer <NUM>. Here, the first metal bonding layer <NUM>, the metal conductive layer <NUM>, and the second metal bonding layer <NUM> are substantially the same as the first metal bonding layer <NUM>, the metal conductive layer <NUM>, and the second metal bonding layer <NUM> described with reference to <FIG>, respectively.

Subsequently, as illustrated in <FIG>, the mother electrode <NUM> is patterned to form a plurality of second electrodes <NUM> and an unseparated electrode pattern <NUM>. The unseparated electrode pattern <NUM> is a residual electrode pattern remaining after a plurality of second electrodes <NUM> are formed from the mother electrode <NUM>, and is an electrode pattern which will be separated to become a plurality of first electrodes <NUM>. <FIG> is a plan view corresponding to <FIG>. As illustrated in <FIG>, the unseparated electrode pattern <NUM> has a shape of one electrode pattern which surrounds the second electrode <NUM> and is disposed over the circuit board <NUM> (i.e., which is not divided for each of pixels PX1, PX2, and PX3). In an embodiment, the unseparated electrode pattern <NUM> may have a mesh structure.

That is, among the first and second electrodes <NUM> and <NUM> described with reference to <FIG> and <FIG>, only the second electrode <NUM> (and the unseparated electrode pattern <NUM>) required for alignment of the light-emitting elements <NUM> may be preferentially patterned or formed.

As described with reference to <FIG>, the second electrode <NUM> may have a tapered shape and the unseparated electrode pattern <NUM> has a tapered shape. The second electrode <NUM> may have a taper angle of <NUM> degrees or less, and the unseparated electrode pattern <NUM> formed by patterning from the same mother electrode <NUM> may have the same taper angle as the taper angle of the second electrode <NUM>.

Subsequently, as illustrated in <FIG>, a fifth insulating layer <NUM> is formed to cover the second electrode <NUM> and the unseparated electrode pattern <NUM>.

Subsequently, referring to <FIG>, a pixel wall <NUM> is formed on the fifth insulating layer <NUM>, and the fifth insulating layer <NUM> is patterned to form a first insulating pattern <NUM>, a second insulating pattern <NUM>, and a third insulating pattern <NUM>. The patterning of the fifth insulating layer <NUM> may be performed after the pixel wall <NUM> is formed, or after the fifth insulating layer <NUM> is first patterned, the pixel wall <NUM> may be formed.

The pixel wall <NUM> may include a first pixel wall <NUM> and a second pixel wall <NUM>. The first pixel wall <NUM> may be formed on the second insulating pattern <NUM> formed on the unseparated electrode pattern <NUM>, and the second pixel wall <NUM> may be formed on the third insulating pattern <NUM> formed on the second electrode <NUM>. <FIG> is a plan view corresponding to <FIG>. As illustrated in <FIG>, the first pixel wall <NUM> may be disposed to overlap a region of the unseparated electrode pattern <NUM> in which the first electrode <NUM> is formed. That is, the first pixel wall <NUM> may be disposed in a region of each of the pixels PX1, PX2, and PX3.

In some embodiments, the first pixel wall <NUM> may also be disposed between the second electrodes <NUM> adjacent to each other in a second direction D2. That is, the first pixel wall <NUM> may be disposed along the periphery (or adjacent to the periphery) of each of the holes HOL1, HOL2, and HOL3 described with reference to <FIG>. For example, when the first pixel PX1 includes the second electrode <NUM>, the first pixel wall <NUM> may be disposed along an edge of the first pixel PX1. As another example, when the first pixel PX1 includes a plurality of second electrodes <NUM>, the first pixel wall <NUM> may partition regions in which the second electrodes <NUM> are disposed and may also be disposed between the adjacent second electrodes <NUM>.

That is, the first pixel wall <NUM> may have a planar shape that is substantially the same as or similar to the planar shape of the first electrode <NUM> described with reference to <FIG>, and may include bank holes corresponding to the holes HOL1, HOL2, and HOL3 of the first electrode <NUM>.

In this case, a light-emitting element solution S, which will be described below, may be disposed only inside the bank holes, and thus manufacturing costs of the light-emitting device <NUM> may be reduced.

Meanwhile, in <FIG>, the bank holes of the first pixel wall <NUM> are illustrated as having an octagonal planar shape, but the above configuration is exemplary and the present invention is not limited thereto. For example, the bank holes of the first pixel wall <NUM> may have a planar shape, such as a circular shape, a tetragonal shape, a hexagonal shape, an elliptical shape, a rectangular shape, or the like, in a range wider than that of the holes HOL1, HOL2, and HOL3 of the first electrode <NUM>.

Similarly, the second pixel wall <NUM> has a shape similar to the planar shape of the second electrode <NUM>, but the present invention is not limited thereto. The second pixel wall <NUM> may be omitted.

Referring to <FIG>, after the pixel walls <NUM> are formed, the light-emitting element solution S including the light-emitting element <NUM> is loaded on the circuit board <NUM>, and the light-emitting element <NUM> is disposed between the pixel walls <NUM> (or between the unseparated electrode pattern <NUM> and the second electrode <NUM>). Here, the light-emitting element solution S may have a formulation such as ink or paste, and may be any one or more of acetone, water, alcohol, and toluene. However, the present invention is not limited thereto, and any material that may be vaporized at room temperature or by heat may be used without any particular limitation.

In this case, the light-emitting element solution S may be brought into contact with the pixel walls <NUM> and may maintain a hemispherical shape due to surface tension of the light-emitting element solution S. A force may be applied to a region, in which the light-emitting element solution S is brought into contact with the pixel walls <NUM>, in a central direction of the light-emitting element solution S, and the light-emitting element solution S may not overflow from the pixel walls <NUM>. Accordingly, the light-emitting element <NUM> may be prevented from moving to another adjacent pixel.

Referring to <FIG>, after the light-emitting element <NUM> is disposed, alternating current (AC) power may be applied to the light-emitting element <NUM> and the light-emitting element <NUM> may be aligned using dielectrophoresis (DEP).

When a power source V applies power to the unseparated electrode pattern <NUM> and the second electrode <NUM>, an electric field E may be formed between the unseparated electrode pattern <NUM> and the second electrode <NUM>. Here, the power source V may be an external supply source or internal power source of the light-emitting device <NUM>. The power source V may supply AC power or direct current (DC) power having a predetermined amplitude and period. DC power may be repeatedly applied to the unseparated electrode pattern <NUM> and the second electrode <NUM> so that power having a predetermined amplitude and period may be realized.

Bipolarity is induced in the light-emitting element <NUM> under the electric field E, and the light-emitting element <NUM> is subjected to a force toward a larger or smaller inclination of the electric field E due to a DEP force. The light-emitting element <NUM> may be self-aligned between the unseparated electrode pattern <NUM> and the second electrode <NUM> due to the DEP force.

After the light-emitting element <NUM> is aligned, the light-emitting element solution S is vaporized and removed at room temperature or by heat so that the light-emitting element <NUM> may be disposed between the unseparated electrode pattern <NUM> and the second electrode <NUM>.

<FIG> is a plan view corresponding to <FIG>, and the light-emitting elements <NUM> may be arranged or aligned relatively uniformly. The unseparated electrode pattern <NUM> is not divided for each of the pixels PX1, PX2, and PX3, and has a mesh structure as a whole as illustrated in <FIG>, and thus a resistance value of the unseparated electrode pattern <NUM> may be very small compared to the first electrode <NUM> after being separated into individual electrodes. That is, a voltage drop due to the unseparated electrode pattern <NUM> may be very small. Accordingly, the power applied to align the light-emitting element <NUM> may be uniformly applied for each of the pixels PX1, PX2, and PX3, and further, may be uniformly applied for each region in the pixel (e.g., a region adjacent to each second electrode <NUM>), and a very uniform electric field E may be formed between the unseparated electrode pattern <NUM> and the second electrode <NUM>. Therefore, the light-emitting element <NUM> may be arranged relatively uniformly with a uniform direction due to the uniform electric field E so that the light emission efficiency and display quality of the light-emitting device <NUM> may be improved.

In an embodiment, the light-emitting element solution S may include at least one type of light-emitting element <NUM>. In order to align the light-emitting elements <NUM> that emit pieces of light having different colors in the pixels PX1, PX2, and PX3 of the light-emitting device <NUM>, the light-emitting element solution S may include light-emitting elements <NUM> that emit the pieces of light having various colors. Further, the light-emitting elements <NUM> that emit the pieces of light having different colors may be mixed in the light-emitting element solution S. However, the present invention is not limited thereto.

Referring to <FIG>, after the light-emitting elements <NUM> are aligned, a plurality of first electrodes <NUM> are formed by performing a patterning process on the unseparated electrode pattern <NUM>. When the patterning process of the first electrode <NUM> is performed in the same process as the process of forming the second electrode <NUM> described with reference to <FIG> and <FIG>, a second inclination angle of a second inclined surface (i.e., an outer side surface adjacent to or facing another first electrode) of the first electrode <NUM> may be substantially the same as a first inclination angle of a first inclined surface (i.e., an inner side surface adjacent to or facing a second electrode <NUM>) of the first electrode <NUM>.

However, since the first electrode <NUM> is formed at a time point different from a time point at which the second electrode <NUM> is formed, environmental factors that cannot be controlled through process equipment may vary. Accordingly, the second inclination angle of the second inclined surface of the first electrode <NUM> may be different from the first inclination angle of the first inclined surface. Further, since the second inclined surface of the first electrode <NUM> is not in direct contact with the light-emitting element <NUM> and does not function as a reflective electrode, the second inclination angle of the second inclined surface of the first electrode <NUM> may not need to be limited to a range of the first inclination angle of the first inclined surface. Furthermore, as the second inclination angle of the second inclined surface of the first electrode <NUM> decreases, separation distances between the pixels PX1, PX2, and PX3 increase and thus, as the second inclination angle of the second inclined surface of the first electrode <NUM> increases, the density of the pixels PX1, PX2, and PX3 may increase. Therefore, the second inclination angle of the second inclined surface of the first electrode <NUM> may be different from the first inclination angle of the first inclined surface and, for example, the second inclination angle of the second inclined surface of the first electrode <NUM> may be greater than the first inclination angle of the first inclined surface.

After the first electrode <NUM> is patterned, a sixth insulating layer <NUM> and a seventh insulating layer <NUM> are formed on the light-emitting element <NUM> as illustrated in <FIG>.

Thereafter, as illustrated in <FIG>, a first contact electrode <NUM> is formed on the first electrode <NUM>. The first contact electrode <NUM> is formed to cover the first electrode <NUM>, and some regions of the first contact electrode <NUM> may be in contact with the light-emitting element <NUM> and the seventh insulating layer <NUM>.

Referring to <FIG>, subsequently, an eighth insulating layer <NUM> is formed on the first contact electrode <NUM>. The eighth insulating layer <NUM> may be formed to cover the first contact electrode <NUM> and expose the second electrode <NUM>. The eighth insulating layer <NUM> may cover one end portion (i.e., one end portion in a direction in which the second electrode <NUM> is disposed) of the first contact electrode <NUM>, and may cover one side surface (i.e., one side surface in the direction in which the second electrode <NUM> is disposed) of the seventh insulating layer <NUM>.

Referring to <FIG>, subsequently, a second contact electrode <NUM> is formed on an upper surface of the second electrode <NUM>. The second contact electrode <NUM> may be in partial contact with the second electrode <NUM>, the light-emitting element <NUM>, the seventh insulating layer <NUM>, and the eighth insulating layer <NUM>. The second contact electrode <NUM> may be formed even on some regions of an upper portion of the eighth insulating layer <NUM>. By the eighth insulating layer <NUM>, the second contact electrode <NUM> may be physically separated from the first contact electrode <NUM> and the second contact electrode <NUM> may be prevented from being in direct contact with the first contact electrode <NUM>.

Thereafter, as illustrated in <FIG>, a passivation layer <NUM> may be formed to cover the eighth insulating layer <NUM> and the second contact electrode <NUM>.

The light-emitting device <NUM> may be manufactured through a series of processes described with reference to <FIG>. In the manufacturing process of the light-emitting device <NUM>, all of the first electrode <NUM> and second electrodes <NUM> having an inclined surface are formed from one mother electrode <NUM>, and thus the manufacturing process of the light-emitting device <NUM> may be simplified compared to the manufacturing process of the light-emitting device including separate walls, electrodes, reflective electrodes and the like.

Further, the light-emitting elements <NUM> are aligned in a state in which only the second electrode <NUM> is patterned, and thus the alignment efficiency of the light-emitting element <NUM> and the light emission efficiency and display quality of the light-emitting device <NUM> may be improved.

Furthermore, the pixel wall <NUM> is formed to separate not only the pixels PX1, PX2, and PX3, but also the respective second electrodes <NUM>, and thus the light-emitting solution S may be prevented from being provided to unnecessary regions and the manufacturing costs of the light-emitting device <NUM> may be reduced.

<FIG> is a cross-sectional view illustrating an example of the light-emitting device taken along line II-II' of <FIG>.

Referring to <FIG>, <FIG>, and <FIG>, a light-emitting device 10_1 may include pixels PX1, PX2, and PX3, and may include a light-emitting element layer <NUM> constituting the pixels PX1, PX2, and PX3 and a color conversion unit <NUM>.

The pixels PX1, PX2, and PX3 may emit pieces of light having different colors. For example, a first pixel PX1 may emit light having a first color L1, the second pixel PX2 may emit light having a second color L2, and the third pixel PX3 may emit light having a third color L3. However, the present invention is not limited thereto and, in some cases, adjacent pixels may emit light having the same color.

In an embodiment, a central wavelength band of the first color L1 is longer than a central wavelength band of the second color L2, and the central wavelength band of the second color L2 is longer than a central wavelength band of the third color L3. For example, the first color L1 may be a red color having a central wavelength band in a range of about <NUM> to <NUM>, the second color L2 may be a green color having a central wavelength band in a range of about <NUM> to <NUM>, and the third color L3 may be a blue color having a central wavelength band in a range of about <NUM> to <NUM>. However, the present invention is not limited thereto, and the first color L1, the second color L2, and the third color L3 are not particularly limited in a range having different central wavelength bands.

Each of the light-emitting element layer <NUM> and the color conversion unit <NUM> may include a region overlapping each of the pixels PX1, PX2, and PX3 of the light-emitting device 10_1. For convenience of description, the region in which the light-emitting element layer <NUM> overlaps the first pixel PX1 is defined as a first pixel portion, the region in which the light-emitting element layer <NUM> overlaps the second pixel PX2 is defined as a second pixel portion, and the region in which the light-emitting element layer <NUM> overlaps the third pixel PX3 is defined as a third pixel portion. Similarly, the region in which the color conversion unit <NUM> overlaps the first pixel PX1 is defined as a first pixel layer, the region in which the color conversion unit <NUM> overlaps the second pixel PX2 is defined as a second pixel layer, and the region in which the color conversion unit <NUM> overlaps the third pixel PX3 is defined as a third pixel layer.

Since the first to third pixel portions of the light-emitting element layer <NUM> are substantially the same as those of the light-emitting element layer <NUM> of the light-emitting device <NUM> described with reference to <FIG>, overlapping descriptions will not be repeated.

The light-emitting element layer <NUM> may include the light-emitting element <NUM> and emit light in a specific wavelength band so that the light may be provided to the color conversion unit <NUM>. The color conversion unit <NUM> may convert the light in the specific wavelength band provided from the light-emitting element layer <NUM> into light in another wavelength band. The color conversion unit <NUM> may include a support substrate <NUM>, a color conversion layer <NUM>, a color filter layer <NUM>, a light blocking member BM, and a planarization layer OC.

The support substrate <NUM> may support the color filter layer <NUM>, the color conversion layer <NUM>, the light blocking member BM, and the like disposed therebelow. The support substrate <NUM> may emit light provided from the light-emitting element layer <NUM> to the outside of the light-emitting device 10_1.

The support substrate <NUM> may be a transparent insulating substrate. For example, the support substrate <NUM> may include glass, quartz, or a light-transmitting plastic material, but the present invention is not limited thereto.

The light blocking member BM may be disposed below the support substrate <NUM>. The light blocking member BM may be a region in which the transmission of the light provided from the light-emitting element layer <NUM> is substantially blocked. Accordingly, the mixing of light emitted from the pixel layers may be prevented and thus color reproducibility may be improved. The light blocking member BM may be disposed in a predetermined pattern. For example, the light blocking member BM may have a lattice pattern surrounding the pixel layers.

The light blocking member BM may include a material having a high absorption rate for visible light. For example, the light blocking member BM may include a metal such as chromium, a metal nitride, a metal oxide, or a resin material colored in black, but the present invention is not limited thereto.

The color conversion layer <NUM> may convert light incident from the light-emitting element layer <NUM> into light in another wavelength band. For example, when light having a blue color L3 is incident from the light-emitting element layer <NUM>, the color conversion layer <NUM> may convert the light having the blue color L3 into light having a green color L2. However, the present invention is not limited thereto.

The color conversion layer <NUM> may be disposed between the light blocking members BM which are disposed below the support substrate <NUM> to be spaced apart from each other. However, the present invention is not limited thereto, and a portion of the color conversion layer <NUM> may be disposed to overlap at least a portion of the light blocking member BM. For example, the color conversion unit <NUM> may include first to third color conversion layers, and the first to third color conversion layers may convert the incident light into pieces of light having different colors and emit the pieces of light.

The color conversion layer <NUM> may include color conversion particles <NUM> that convert incident first light in an arbitrary wavelength band into light in a wavelength band different from that of the first light. The color conversion particles <NUM> may be a quantum dot material or a phosphor material.

In the case in which the color conversion particles <NUM> are quantum dot materials, when the first light in an arbitrary wavelength band is incident, electrons in a valence band (VB) of the quantum dot material are excited to a conduction band (CB) level. The second light in the wavelength band of the converted light may be emitted while the electrons transition back to the VB. When the color conversion particles <NUM> are quantum dot materials, the wavelength of the emitted light may be controlled by adjusting the particle size of the quantum dot materials. For example, the particle size of the quantum dot material may have a diameter in a range of about <NUM>Å to <NUM>Å, and blue light may be incident to emit red light. Further, the particle size of the quantum dot material may have a diameter in a range of about <NUM>Å to <NUM>Å, and blue light may be incident to emit green light. However, the present invention is not limited thereto.

The color conversion particles <NUM> may be dispersed in a light-transmitting resin R. Any material may be used as the light-transmitting resin R without any particular limitation as long as the material does not adsorb light incident on the color conversion layer <NUM> and does not affect light absorption and emission of the color conversion particles <NUM>. For example, the light-transmitting resin R may include an organic material such as an epoxy resin, an acrylic resin, or the like, but the present invention is not limited thereto. The color conversion layer <NUM> including the color conversion particles <NUM> may be formed using various processes such as an ink jet injection method, a photoresist (PR) method, and the like, but the present invention is not limited thereto.

The color filter layer <NUM> may be disposed between the color conversion layer <NUM> and the support substrate <NUM>. The color filter layer <NUM> may be a layer for determining a color of the light incident from the light-emitting element layer <NUM> and passing through the color conversion layer <NUM> and being finally displayed on the pixels PX1, PX2, and PX3 of the light-emitting device <NUM>.

The color filter layer <NUM> may function as a color-transmissive layer for transmitting incident light without change. However, the present invention is not limited thereto, and the color filter layer <NUM> may be a color filter or a wavelength-selective optical filter that transmits the first light in an arbitrary wavelength band but blocks the second light, the third light, or the like in other wavelength bands.

The color filter layer <NUM> may include a transparent organic film and may function as a color-transmissive layer for transmitting incident light without change. Further, in order to increase the color purity of the transmitted color, the color filter layer <NUM> may include a colorant having a color in an arbitrary wavelength band. The colorant may be dispersed in the transparent organic film of the color filter layer <NUM>. However, the present invention is not limited thereto.

The color filter layer <NUM> may include a first color filter layer <NUM>, a second color filter layer <NUM>, and a third color filter layer <NUM>. The first color filter layer <NUM>, the second color filter layer <NUM>, and the third color filter layer <NUM> may be disposed on the first to third pixel layers. Pieces of light incident on the color conversion layer <NUM> from each of the pixel portions of the light-emitting element layer <NUM> may have different colors. Accordingly, in order to control the color displayed on each of the pixels PX1, PX2, and PX3 of the light-emitting device 10_1, the color filter layer <NUM> may be selectively disposed on the pixel layers.

For example, the first color filter layer <NUM> may be disposed on the first pixel layer and may function as a color-transmissive layer for transmitting incident light without change. The second color filter layer <NUM> and the third color filter layer <NUM> may be disposed on the second pixel layer and the third pixel layer, respectively, and may function as color filters that transmit only light in a specific wavelength band and block or reflect other pieces of light. However, the present invention is not limited thereto, and all of the first color filter layer <NUM>, the second color filter layer <NUM>, and the third color filter layer <NUM> may function as color filters. For example, the first color filter layer <NUM> may transmit light having a red color L1, the second color filter layer <NUM> may transmit light having a green color L2, and the third color filter layer <NUM> may transmit light having a blue color L3.

A capping layer CL may be disposed on an outer surface of the color conversion layer <NUM> to cover and protect the color conversion particles <NUM>, the light-transmitting resin R, or the like. The capping layer CL may include an inorganic material. For example, the capping layer CL may include at least one of silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiOxNy), but the present invention is not limited thereto.

The planarization layer OC may be disposed below the color conversion layer <NUM>, the color filter layer <NUM>, the light blocking member BM, and the like. The planarization layer OC may be disposed to cover all of the members disposed below the support substrate <NUM>. Accordingly, the planarization layer OC may planarize a lower surface of the color conversion unit <NUM> to minimize a step difference caused by the members disposed below the support substrate <NUM>. Since the lower surface of the color conversion unit <NUM> is planarized by the planarization layer OC, the light-emitting device <NUM> may be manufactured by bonding with the light-emitting element layer <NUM> manufactured through a separate process.

The planarization layer OC may include an organic material. For example, the planarization layer OC may include a thermosetting resin. For example, the planarization layer OC may include at least one selected from the group consisting of a cardo resin, a polyimide resin, an acrylic resin, a siloxane resin, and a silsesquioxane resin, but the present invention is not limited thereto.

When the color conversion unit <NUM> and the light-emitting element layer <NUM> are manufactured by separate processes and bonded, the color conversion unit <NUM> and the light-emitting element layer <NUM> may be bonded by an adhesive layer PSI. The adhesive layer PSI may be disposed on an upper surface of the light-emitting element layer <NUM> and the surface planarized by the planarization layer OC of the color conversion unit <NUM>, and the light-emitting element layer <NUM> and the color conversion unit <NUM> may be coupled to each other.

Any material may be used as the adhesive layer PSI without any particular limitation as long as the material is a type of material that may bond a plurality of members to be adhered. For example, the adhesive layer PSI may be made of an optical clear adhesive (OCA), an optical clear resin (OCR), a pressure sensitive adhesive (PSA), or the like.

As described with reference to <FIG>, the light-emitting device 10_1 may include one type of light-emitting element <NUM> and further include the color conversion unit <NUM> that realizes the red color L1, the green color L2, and the blue color L3, and thus the light-emitting device 10_1 may be implemented as a display device that displays an image.

<FIG> is a cross-sectional view illustrating another example of the light-emitting device taken along line I-I' of <FIG>.

Referring to <FIG>, <FIG>, and <FIG>, a light-emitting device 10_2 of <FIG> is different from the light-emitting device <NUM> described with reference to <FIG> in that a fourth insulating layer 310_1 has a convex portion and a first electrode 330_1 and a second electrode 330_2 are disposed on the convex portion of the fourth insulating layer 310_1. Except for the fourth insulating layer 310_1, the first electrode 330_1, and the second electrode 330_2, the light-emitting device 10_2 is substantially the same as or similar to the light-emitting device <NUM> of <FIG>. Therefore, overlapping descriptions will not be repeated.

The convex portion may be formed in an upper surface of the fourth insulating layer 310_1. As illustrated in <FIG>, a portion of the upper surface of the fourth insulating layer 310_1 overlapping (or in contact with) a second electrode 340_1 may protrude upward as compared to other portions. For example, a portion of the upper surface of the fourth insulating layer 310_1 may protrude upward from an edge of a lower surface of the second electrode 340_1 along a closed loop which is positioned inside the second electrode 340_1 by a thickness of the second electrode 340_1. A thickness of the convex portion of the fourth insulating layer 310_1 is not limited but may be, for example, <NUM>,<NUM>Å or <NUM>,<NUM>Å or more.

Similarly, a portion of the upper surface of the fourth insulating layer 310_1 overlapping a first electrode 330_1 may protrude upward as compared to other portions. For example, a portion of the upper surface of the fourth insulating layer 310_1 may protrude upward from an edge of a lower surface of the first electrode 330_1 along a closed loop which is positioned inside the first electrode 330_1 by a thickness of the first electrode 330_1.

The first electrode 330_1 and the second electrode 340_1 may be substantially the same as the first electrode <NUM> and the second electrode <NUM> described with reference to <FIG> except for thicknesses thereof. Therefore, overlapping descriptions will not be repeated.

The convex portion is formed in the upper surface of the fourth insulating layer 310_1, and thus the thickness of the first electrode 330_1 and the thickness of the second electrode 340_1 may be relatively reduced. For example, when the thickness of the first electrode <NUM> and the thickness of the second electrode <NUM> illustrated in <FIG> is about <NUM>,<NUM>Å and the thickness of the convex portion of the fourth insulating layer 310_1 is about <NUM>,<NUM>Å, the thickness of the first electrode 330_1 and the thickness of the second electrode 340_1 illustrated in <FIG> may be about <NUM>,<NUM>Å.

The first electrode 330_1 and the second electrode 340_1 may have inclined surfaces due to the convex portion of the fourth insulating layer 310_1. Therefore, the first electrode 330_1 and the second electrode 340_1 having an inclined surface with a specific inclination angle (e.g., an angle of <NUM> degrees or less) may be more easily formed.

As described with reference to <FIG>, the convex portion may be formed in the upper surface of the fourth insulating layer 310_1 (or the circuit board <NUM>) and, in this case, the first and second electrodes 330_1 and 340_1 having a taper angle sufficient to reflect light emitted from a side surface of a light-emitting element <NUM> may be more easily formed.

<FIG> is a plan view illustrating a light-emitting device according to another embodiment. <FIG> is an enlarged view of region AA of <FIG>.

Referring to <FIG>, <FIG>, and <FIG>, a light-emitting device 10_3 may include first to third pixels PX1_1, PX2_1, and PX3_1. Since the first to third pixels PX1_1, PX2_1, and PX3_1 are substantially identical to each other, common characteristics of the first to third pixels PX1_1, PX2_1, and PX3_1 will be described based on the first pixel PX1_1.

The first pixel PX_1 is different from the first pixel PX1 described with reference to <FIG> in that the first pixel PX1_1 includes first electrodes 330_2 and second electrodes 340_2. The first electrode 330_2 and the second electrode 340_2 may be substantially the same as or similar to the first electrode <NUM> and the second electrode <NUM> described with reference to <FIG> and <FIG> except for shapes thereof. Therefore, overlapping descriptions will not be repeated.

The plurality of second electrode 340_2 may be provided, and three second electrodes 340_2 may be provided in the first pixel PX1_1, similar to the second electrode <NUM> illustrated in <FIG>. The above configuration is exemplary and the present invention is not limited thereto. For example, one second electrode 340_2, two second electrodes 340_2, or four or more second electrodes 340_2 may be included in the first pixel PX1_1.

As illustrated in <FIG>, the second electrode 340_2 may include a central portion 340a, a first peripheral portion 340b, and a first connection portion 340c.

The central portion 340a may have a circular planar shape and may have a specific area or a specific size. The central portion 340a may have an area greater than a planar area of the contact hole 319_2 described with reference to <FIG>.

The first peripheral portion 340b may be spaced apart from the central portion 340a to extend along an outer surface of the central portion 340a and may have both ends spaced apart from each other. For example, the peripheral portion 340b may have a planar shape of a reverse C shape or a ring shape in which a portion is cut.

The first connection portion 340c may connect the central portion 340a to the first peripheral portion 340b. The first connection portion 340c may extend from the central portion 340a in a specific direction (e.g., a first direction D1) to be connected to the first peripheral portion 340b.

Meanwhile, the first electrode 330_2 may have a shape corresponding to the second electrode 340_2, may be spaced apart from the second electrode 340_2, and may surround the entirety of the second electrode 340_2.

The first electrode 330_2 may include a main body portion 330a having a hole therein, a second peripheral portion 330b disposed in the hole, and a second connection portion 330c which extends from the main body portion and is connected to the second peripheral portion 330b. The second electrode 340_2 may be disposed in the hole of the main body portion 330a. The second peripheral portion 330b may be disposed between the central portion 340a and the first peripheral portion 340b of the second electrode 340_2. The second peripheral portion 330b may be spaced apart from the central portion 340a of the second electrode 330_2 to extend along the outer surface of the central portion 340a, and may have both ends spaced apart from each other with the first connection portion 340c of the second electrode 330_2 interposed therebetween. The second peripheral portion 330b may have a planar shape that is the same as or similar to the planar shape of the first peripheral portion 340b. The second connection portion 330c may extend across both ends of the first peripheral portion 340b of the second electrode 340_2, and may connect the second peripheral portion 330b to the main body portion 330a.

The first electrode 330_2 may be spaced a predetermined interval from the second electrode 340_2 along an edge of the second electrode 340_2. The light-emitting element <NUM> may be disposed between the first electrode 330_2 and the second electrode 340_2 (or in a space between the first electrode 330_2 and the second electrode 340_2).

As illustrated in <FIG>, the light-emitting device 10_3 may have a region in which the light-emitting elements formed by three concentric circles are arranged. Accordingly, the density and arrangement efficiency of the light-emitting element <NUM> may be improved, and the light emission characteristics (e.g., maximum luminance) of the light-emitting device 10_3 may be improved.

Meanwhile, in <FIG> and <FIG>, the shape of the first electrode 330_2 (or the shape of the second peripheral portion 330b), and the shape of the second electrode 340_2 (or the shape of the central portion 340a, the shape of the first peripheral portion 340b) are illustrated as having a ring shape, but the present invention is not limited thereto. For example, an outermost portion of the first peripheral portion 340b of the second electrode 340_2 may have a shape such as a polygonal shape such as a triangular shape, a rectangular shape, a hexagonal shape, an octagonal shape, or the like, or an elliptical shape. The shape of the second electrode 340_2 is not limited to a specific shape as long as the shape is an island shape that is independently disposed from other electrodes.

<FIG> is a cross-sectional view illustrating an example of the light-emitting device taken along line III-III' of <FIG>.

Referring to <FIG> and <FIG>, a light-emitting device 10_3 of <FIG> may be substantially the same as the light-emitting device <NUM> of <FIG> except for the number of light-emitting elements <NUM> included therein. Therefore, overlapping descriptions will not be repeated.

As illustrated in <FIG> and <FIG>, three light-emitting elements <NUM> may be disposed between the edge of the second electrode 340_2 and the center of an area of the second electrode 340_2.

Referring to <FIG>, from left to right, a first electrode 330_2 (or a main body portion 330a), a second electrode 340_2 (or a first peripheral portion 340b), a first electrode 330_2 (or a second peripheral portion 330b), and a second electrode 340_2 (or a central portion 340a) may be sequentially disposed, and the light-emitting elements <NUM> may be disposed between the above components.

A structure of a light-emitting portion between the main body portion 330a and the first peripheral portion 340b may be the same as a structure of the light-emitting element layer <NUM> illustrated in <FIG>, a structure of a light-emitting portion between the first peripheral portion 340b and the second peripheral portion 330b may be the same as a structure in which left and right sides of the light-emitting element layer <NUM> illustrated in <FIG> are reversed, and a structure of a light-emitting portion between the second peripheral portion 330b and the central portion 340a may be the same as a structure of the light-emitting element layer <NUM> illustrated in <FIG>.

<FIG> is a cross-sectional view illustrating another example of the light-emitting device taken along line III-III' of <FIG>.

Referring to <FIG>, the light-emitting device 10_4 of <FIG> is different from the light-emitting device 10_3 of <FIG> in that the light-emitting device 10_4 does not include a second pixel wall <NUM>.

In the light-emitting device 10_4, light-emitting elements <NUM> having relatively high density (or a large number of light-emitting elements <NUM>) are disposed over an entire pixel region (e.g., a region in which the first pixel PX1 is disposed), and thus the second pixel wall <NUM> may not be required. In this case, a light-emitting element solution S including the light-emitting elements <NUM> may be disposed in a space formed by a pixel wall <NUM> on a pixel region.

Claim 1:
A light-emitting device (<NUM>) comprising:
a substrate (<NUM>);
a first electrode (<NUM>) which is disposed on the substrate (<NUM>), includes holes (HOL1, HOL2, HOL3), and has inclined surfaces (332_S1) formed along peripheries of the holes (HOL1, HOL2, HOL3);
second electrodes (<NUM>) which are disposed on the substrate (<NUM>) and each disposed in one of the holes (HOL1, HOL2, HOL3) of the first electrode (<NUM>); and
light-emitting elements (<NUM>) which are disposed between the first electrode (<NUM>) and the second electrodes (<NUM>) and electrically connected to the first electrode (<NUM>) and the second electrodes (<NUM>),
wherein the first electrode (<NUM>) includes a first metal bonding layer (<NUM>), a metal conductive layer (<NUM>) disposed on the first metal bonding layer (<NUM>), and a second metal bonding layer (<NUM>) disposed on the metal conductive layer (<NUM>),
the metal conductive layer (<NUM>) has a thickness which is greater than a thickness of the first metal bonding layer (<NUM>) and greater than a thickness of the second metal bonding layer (<NUM>), and
the inclined surfaces (332_S1) are formed on the metal conductive layer (<NUM>).