KR20190069355A - Pixel Structure And Display Apparatus Including The Same - Google Patents

Abstract

Disclosed is a pixel structure and a display device including the same. According to one embodiment of the present invention, a micro LED electrode assembly can comprise: a base substrate; a first electrode part disposed on the base substrate; a second electrode part having a circular shape extending in a circumferential direction around the first electrode part; and a plurality of LED elements, each of which is connected to the first electrode part and the second electrode part, and wherein each is radially disposed in a different direction. Therefore, an objective of the present invention is to provide the pixel structure and the display device including the same, capable of preventing abnormal misalignment of a micro LED element by aligning and connecting independently manufactured nano-sized micro LED element between two different electrodes.

Description

[0001] The present invention relates to a pixel structure and a display device including the pixel structure,

Embodiments of the present invention relate to a pixel structure and a display device including the pixel structure.

LED devices have high light conversion efficiency, very low energy consumption, and are semi-permanent and environmentally friendly. Accordingly, LED devices are used in many fields such as traffic lights, mobile phones, automobile headlights, outdoor display boards, LCD backlights (BLUs), and indoor and outdoor lighting.

In order to utilize the LED element in illumination, display, etc., it is necessary to connect the LED element and the electrode capable of applying power to the LED element, The arrangement relationship of the electrodes has been studied variously.

The arrangement of the LED element and the electrode can be classified into a method of directly growing the LED element on the electrode and a method of independently growing the LED element separately and then arranging the LED element on the electrode. In the case of the latter method, a conventional three-dimensional LED element can be connected to the electrode by erecting the three-dimensional LED element. However, when the LED element is very small in nano unit, it is difficult to make the LED element stand upright on the electrode.

Korean Registered Patent Publication No. KR 10-1244926 (Mar. 13, 2013)

Embodiments of the present invention are directed to a pixel structure and a display device including the pixel structure that can prevent abnormal misalignment of an ultra-small LED element by aligning and connecting independently manufactured nano-sized miniature LED elements between two different electrodes to provide.

According to one aspect of the present invention, there is provided a semiconductor device comprising: a base substrate; A first electrode unit disposed on the base substrate; A second electrode part having a circular shape extending in a circumferential direction about the first electrode part; And a plurality of LED elements connected to the first electrode portion and the second electrode portion, each of the plurality of LED elements being radially arranged along a different direction.

According to an embodiment, one end of each of the plurality of LED elements may be positioned on the first electrode portion and the other end may be positioned on the second electrode portion.

According to an embodiment, one end of each of the plurality of LED elements may be directly connected to the first electrode unit, and the other end may be directly connected to the second electrode unit.

According to an embodiment of the present invention, two LED elements adjacent to each other among the plurality of LED elements are arranged in a first direction and in a second direction intersecting the first direction, and the first direction and the second direction Can achieve an acute angle.

According to an embodiment, imaginary lines extending from different directions in which each of the plurality of LED elements is disposed may meet at a virtual contact point, and the virtual contact point may be located within the first electrode portion.

According to one embodiment, the second electrode unit may have an annular shape having a closed curve.

According to an embodiment, the first electrode portion may have a circular shape and be positioned at the center of the second electrode portion.

According to one embodiment, the driving transistor is electrically connected to the first electrode unit. And a power supply line electrically connected to the second electrode unit.

According to an exemplary embodiment, the first and second electrode units may include a plurality of electrode lines connecting the plurality of second electrode units.

According to an embodiment, the distance between the first electrode part and the second electrode part may be 1 μm or more and 7 μm or less.

According to an embodiment, the second electrode portion includes a first sub-electrode portion and a second sub-electrode portion in a semicircular shape, and the first sub-electrode portion and the second sub-electrode portion may be separated from each other and spaced apart from each other .

According to an embodiment, a driving transistor electrically connected to the first electrode unit is provided. And a power supply line electrically connected to the first sub-electrode unit and the second sub-electrode unit, respectively.

According to one embodiment, the first electrode unit and the second electrode unit are provided in plurality, and the first electrode line connects the plurality of first sub-electrode units. And a second electrode line connecting the plurality of second sub-electrode units.

According to an embodiment, the first distance between the first sub-electrode part and the first electrode part and the second distance between the second sub-electrode part and the first electrode part may be different from each other.

According to one embodiment, the first spacing distance and the second spacing distance may be 1 μm or more and 7 μm or less.

According to an embodiment, one end of each of the plurality of LED elements may be positioned on the first electrode portion and the other end may be positioned on the first sub-electrode portion or the second sub-electrode portion.

According to one embodiment, one end of each of the plurality of LED elements may be directly connected to the first electrode unit, and the other end may be directly connected to the first sub-electrode unit or the second sub-electrode unit.

According to another aspect of the present invention, a driving circuit connected to the pixel structure may be included.

As described above, the pixel structure according to the embodiments of the present invention can be manufactured by arranging and connecting the independently manufactured nanosize-sized microfabricated LED elements between two different electrodes so that the microfabricated LED element is bonded to the micro- One-to-one correspondence can be overcome.

In addition, even when a very small LED element of a conventional shape is used, the alignment between the ultra-small LED element and the electrode is maintained, thereby minimizing the defective rate of the pixel structure.

In addition, it is possible to concentrically arrange and connect the miniature LED elements in a desired mounting area including different electrodes.

1 is a perspective view of a pixel structure according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the pixel structure shown in FIG. 1 taken along line AA '. FIG.
3 is a perspective view of an ultra-small LED device according to an embodiment of the present invention.
4A is a perspective view of a pixel structure according to an embodiment of the present invention. 4B is a schematic diagram of a pixel structure according to an embodiment of the present invention. 4C is a perspective view of a pixel structure according to an embodiment of the present invention. 4D is a schematic diagram of a pixel structure according to an embodiment of the present invention.
5A is a perspective view of a pixel structure according to another embodiment of the present invention.
5B is a cross-sectional view of the pixel structure taken along line BB 'of the pixel structure shown in FIG. 5A.
6A is a perspective view of a pixel structure according to another embodiment of the present invention. 6B is a schematic diagram of a pixel structure according to another embodiment of the present invention. 6C is a perspective view of a pixel structure according to another embodiment of the present invention. 6D is a schematic diagram of a pixel structure according to another embodiment of the present invention.
7 is a conceptual view of a display device according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention and methods of achieving them will be apparent with reference to the embodiments described in detail below with reference to the drawings. However, the present invention is not limited to the embodiments described below, but may be implemented in various forms.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or corresponding components throughout the drawings, and a duplicate description thereof will be omitted .

In the following embodiments, the terms first, second, etc. are used for the purpose of distinguishing one element from another element, rather than limiting.

In the following examples, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

In the following embodiments, terms such as inclusive or possessive are intended to mean that a feature, or element, described in the specification is present, and does not preclude the possibility that one or more other features or elements may be added.

In the drawings, components may be exaggerated or reduced in size for convenience of explanation. For example, the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, and thus the present invention is not necessarily limited to those shown in the drawings.

1 is a perspective view of a pixel structure according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the pixel structure shown in FIG. 1 taken along the line A-A '. 3 is a perspective view of an ultra-small LED device according to an embodiment of the present invention.

1 to 3, a pixel structure 1 according to an embodiment of the present invention includes a base substrate 10, a first electrode portion 21 disposed on the top of the base substrate 10, A micro-LED element 40, and a solvent 50. The micro- The plurality of pixel structures 1 may be arranged in a display area of a display device 1000 (see FIG. 7) to be described later.

The base substrate 10 is a substrate on which the first and second electrode portions 21 and 22 can be arranged and is made of any one of a glass substrate, a quartz substrate, a sapphire substrate, a plastic substrate, and a flexible polymer film However, the present invention is not limited thereto. The area of the base substrate 10 according to one example is determined by the area of the first and second electrode portions 21 and 22 that can be disposed on the base substrate 10 and the area of the first and second The size of the micro LED element 40 disposed between the electrode portions 21 and 22 and the number of the micro LED elements 40 can be varied.

On the base substrate 10, a buffer layer 601 may be further included. The buffer layer 601 prevents impurity ions from diffusing on the upper surface of the base substrate 10, prevents penetration of moisture or outside air, and can flatten the surface. In some embodiments, the buffer layer 601 is formed of an inorganic material such as silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, aluminum nitride, titanium oxide or titanium nitride, or an organic material such as polyimide, polyester, Or a laminate thereof. The buffer layer 601 is not an essential component and may not be provided if necessary. The buffer layer 601 may be formed by various deposition methods such as plasma enhanced chemical vapor deposition (PECVD), atmospheric pressure CVD (APCVD), and low pressure CVD (LPCVD).

The first thin film transistor TFT1 is composed of a first active layer 611, a first gate electrode 612, a first drain electrode 613, and a first source electrode 614. A first gate insulating layer 602 may be interposed between the first gate electrode 612 and the first active layer 611 for insulation therebetween. The first gate electrode 612 is formed to overlap with a portion of the first active layer 611 on the first gate insulating film 602. The first thin film transistor TFT1 may be a driving thin film transistor which is disposed under the very small LED element 40 and drives the ultra-small LED element 40. [

The second thin film transistor TFT2 is composed of a second active layer 621, a second gate electrode 622, a second drain electrode 623 and a second source electrode 624. A first gate insulating layer 602 for insulating therebetween may be interposed between the second gate electrode 622 and the second active layer 621. The second gate electrode 622 is formed to overlap with a portion of the second active layer 621 on the first gate insulating film 602.

The first active layer 611 and the second active layer 621 may be provided on the buffer layer 601. The first active layer 611 and the second active layer 621 may be formed of an inorganic semiconductor such as amorphous silicon or polysilicon or an organic semiconductor. In some embodiments, the first active layer 611 may be formed of an oxide semiconductor. For example, the oxide semiconductor may be a Group 12, 13, or Group 14 metal such as Zn, In, Ga, Cd, Ge, ≪ / RTI > elements and combinations thereof.

A first gate insulating layer 602 is provided on the buffer layer 601 to cover the first active layer 611 and the second active layer 621. A second gate insulating layer 603 is formed to cover the first gate electrode 612 and the second gate electrode 622.

The first gate electrode 612 and the second gate electrode 622 may be formed of a single layer or a multilayer film of Au, Ag, Cu, Ni, Pt, Pd, Al, : W and the like.

The first gate insulating film 602 and the second gate insulating film 603 may include an inorganic film such as silicon oxide, silicon nitride, or metal oxide, and these may be formed as a single layer or may be formed as a multi-layer.

An interlayer insulating film 604 is formed on the second gate insulating film 603. The interlayer insulating film 604 may be formed of an inorganic film such as silicon oxide, silicon nitride, or the like. The interlayer insulating film 604 may include an organic film.

A first drain electrode 613 and a first source electrode 614 are formed on the interlayer insulating film 604. Each of the first drain electrode 613 and the first source electrode 614 is in contact with the first active layer 611 through a contact hole. A second drain electrode 623 and a second source electrode 624 are formed on the interlayer insulating film 604 and the second drain electrode 623 and the second source electrode 624 are formed through a contact hole 2 active layer 621, respectively. The first drain electrode 613, the second drain electrode 623, the first source electrode 614 and the second source electrode 621 may include a metal, an alloy, a metal nitride, a conductive metal oxide, a transparent conductive material, or the like .

The structure of the thin film transistor (TFT) is not limited to this, and various structures of the thin film transistor are applicable. For example, the thin film transistor (TFT) is formed in a top gate structure, but the first gate electrode 612 may be formed in a bottom gate structure disposed under the first active layer 611.

The planarizing film 605 covers the thin film transistors TFT1 and TFT2 and is provided on the interlayer insulating film 604. [ The planarizing film 605 may serve to eliminate the planarization of the film and to planarize the film to increase the luminous efficiency of the ultra-small LED element 40 to be formed thereon. The planarization layer 605 may have a through hole exposing a portion of the first drain electrode 613.

The planarizing film 605 may be formed of an insulator. For example, the planarization layer 605 may be formed of a single layer or a plurality of layers of an inorganic material, an organic material, or an organic / inorganic composite, and may be formed by various deposition methods. In some embodiments, the planarization layer 605 is formed of a material selected from the group consisting of polyacrylates resin, epoxy resin, phenolic resin, polyamides resin, polyimides rein, The resin may be formed of at least one of unsaturated polyesters resin, polyphenylenethers resin, polyphenylenesulfides resin, and benzocyclobutene (BCB). have.

However, the embodiment according to the present disclosure is not limited to the above-described structure, and either the planarizing film 604 or the interlayer insulating film 605 may be omitted in some cases.

The first electrode portion 21 is an electrode portion disposed on the interlayer insulating layer 605 and electrically connected to the ultra-small LED element 40. For example, the first electrode portions 21 may be formed in a plurality of locations, and the plurality of first electrode portions 21 may be spaced apart from each other at an upper portion of the interlayer insulating film 605 with a predetermined gap therebetween have.

In addition, the first electrode unit 21 may be electrically connected to the first drain electrode 613 to receive power. At this time, the first drain electrode 613 may be connected to the first electrode unit 21 using a through hole exposing a part of the first drain electrode 613. [

The first electrode unit 21 may include at least one metal material selected from the group consisting of aluminum, titanium, indium, gold, and silver, or indium tin oxide (ITO), ZnO: Al, and CNT- and a transparent polymer material such as polymethylmethacrylate (PMMA). When the first electrode unit 21 includes two or more kinds of materials, the first electrode unit 21 according to an exemplary embodiment may be formed by stacking two or more kinds of materials.

The second electrode portion 22 is an electrode portion disposed on the interlayer insulating layer 605 and electrically connected to the ultra-small LED element 40. As an example, the second electrode portion 22 may have a circular shape extending along the circumferential direction about the first electrode portion 21. The first electrode unit 21 and the second electrode unit 22 may be spaced apart from each other by a predetermined distance, for example, a first distance D ₁ .

The plurality of second electrode portions 22 may be provided at a predetermined distance from the upper portion of the base substrate 10 so as to be spaced apart from each other Respectively. In addition, the plurality of second electrode units 22 may be connected to each other using the electrode lines 220 according to one embodiment. At this time, the power supply line 630 can be electrically connected to the second electrode unit 22 using the through-hole, so that the plurality of second electrode units 22 can supply power of the same voltage from the power supply line 630 Can be supplied. As an example, a planarization film 640 for planarizing the surface may be disposed under the power supply line 630. However, the planarizing film 640 is not an essential component, and may not be provided if necessary.

In addition, the second electrode unit 22 according to one embodiment may be formed of one or more metal materials selected from the group consisting of aluminum, titanium, indium, gold, and silver, or indium tin oxide (ITO), ZnO: Al and CNT- and a transparent polymer material such as polymethylmethacrylate (PMMA). When the second electrode portion 22 includes two or more kinds of materials, the second electrode portion 22 according to an exemplary embodiment may be formed by stacking two or more kinds of materials. As an example, the materials included in the first electrode portion 21 and the second electrode portion 22 may be the same or different.

The ultra-small LED element 40 is a light emitting element through which light can be emitted, and can be formed into various shapes such as a cylinder, a rectangular parallelepiped, and the like according to an example. 3, the micro-LED device 40 according to an exemplary embodiment includes a first electrode layer 410, a second electrode layer 420, a first semiconductor layer 430, a second semiconductor layer 440, 1 and the second semiconductor layer 430 and 440, respectively. The first electrode layer 410, the first semiconductor layer 420, the active layer 450, the second semiconductor layer 440 and the second electrode layer 420 are sequentially formed in the longitudinal direction of the ultra-small light emitting device 40 . ≪ / RTI > In addition, as an example, the length T of the ultra-small LED element 40 may be 2 탆 to 5 탆, but the present disclosure is not limited thereto.

The first and second electrode layers 410 and 420 may be ohmic contact electrodes. However, the first and second electrode layers 410 and 420 are not limited thereto, and may be a Schottky contact electrode. The first and second electrode layers 410 and 420 may include a conductive metal. For example, the first and second electrode layers 410 and 420 may include one or more metal materials selected from the group consisting of aluminum, titanium, indium, gold, and silver. As an example, the materials included in the first and second electrode layers 410 and 420 may be identical to each other. As another example, the materials contained in the first and second electrode layers 410 and 420 may be different.

The first semiconductor layer 430 according to one embodiment may include, for example, an n-type semiconductor layer. For example, when the ultra-small LED element 40 is a blue light emitting element, the n-type semiconductor layer may be formed of InxAlyGa1-x-yN (0? X? 1, 0? Y? 1, 0? X + Any one or more of a semiconductor material having a composition formula such as InAlGaN, GaN, AlGaN, InGaN, AlN, InN and the like may be selected and doped with a first conductive dopant (e.g., Si, Ge, Sn or the like) But is not limited thereto. In addition, the ultra-small LED element 40 is not limited to a blue light emitting element, and may include another type III-V semiconductor material as an n-type semiconductor layer when light emission colors are different. However, the present disclosure is not limited thereto, and the first electrode layer 410 as an ohmic contact electrode may not be an essential structure. In this case, the first semiconductor layer 430 may be connected to the first electrode unit 21.

The second semiconductor layer 440 according to one embodiment may include, for example, a p-type semiconductor layer. As an example, if a tiny LED element 40 is a blue light emitting device, the p-type semiconductor layer is _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0 ≤y≤1, 0≤x (e.g., Mg) may be doped. However, the second conductive dopant (e.g., Mg) may be doped, but the second conductive dopant may be doped, for example, InAlGaN, GaN, AlGaN, InGaN, AlN, InN, The disclosure is not limited thereto. However, the present disclosure is not limited thereto, and the second electrode layer 420 as an ohmic contact electrode may not be an essential structure. In this case, the second semiconductor layer 440 may be connected to the second electrode portion 22.

The active layer 450 is disposed between the first and second semiconductor layers 430 and 440, and may be formed of, for example, a single or multiple quantum well structure. As an example, a cladding layer (not shown) doped with a conductive dopant may be disposed on the top and / or bottom of the active layer 450, and the cladding layer doped with the conductive dopant may be implemented as an AlGaN layer or an InAlGaN layer have. In addition, materials such as AlGaN and AlInGaN may be used as the active layer 450. When an electric field is applied to the active layer 450, light is generated due to the combination of electron-hole pairs, and the position of the active layer 450 can be variously changed depending on the type of the LED. In addition, the ultra-small LED element 40 is not limited to the blue light emitting device, and other types of III-V semiconductor materials may be included in the active layer 450 when the light emitting colors are different. Although the present invention describes that the first and second semiconductor layers 430 and 440 and the active layer 450 may be included in the ultra-small LED element 40, the present disclosure is not limited thereto. As an example, the ultra-small LED element 40 may further include an additional phosphor layer, an active layer, a semiconductor layer, and / or an electrode layer on top and bottom of the first and second semiconductor layers 430 and 440.

In addition, the ultra miniature LED device 40 according to an exemplary embodiment of the present invention may further include an insulating layer 470 covering an outer surface of the active layer 450. The insulating layer 470 may cover the side surface of the active layer 450 and may be formed when the active layer 450 contacts the first electrode portion 21 or the second electrode portion 22 An electrical short circuit can be prevented. In addition, the insulating film 470 can protect the outer surface of the ultra-small LED element 40 including the active layer 450, thereby preventing a decrease in luminous efficiency.

The solvent 50 is a moving medium for smoothly dispersing and moving the ultrasmall sized LED element 40 according to an embodiment of the present invention. The solvent 50 does not cause physical and chemical damage to the ultraminiature LED element 40, And can be used without limitation as long as the solvent is easy to remove. As one example, the solvent 50 may be any one or more of acetone, water, alcohol, and toluene, but the present disclosure is not limited thereto.

The solvent 50 according to one embodiment of the present invention may be introduced at a predetermined weight ratio to the micro LED device 40 according to an embodiment. The amount of the solvent 50 is excessively large so that the ultra miniature LED element 40 does not reach the desired first and second electrode portions 21 and 22, The number of the ultra-small LED elements 40 mounted on the target mounting region in the first and second electrode portions 21 and 22 can be reduced. Further, when the solvent 50 in a range smaller than a predetermined weight ratio is introduced, there may be a problem in the individual movement and alignment of the ultra-small LED elements 40.

A predetermined power can be applied to the first and second electrode units 21 and 22 using the first drain electrode 613 and the power source wiring 630. [ For example, the first drain electrode 613 may be connected to the first electrode unit 21 to apply power, the power supply line 630 may be connected to the second electrode unit 22 to apply power, Accordingly, an electric field E can be formed between the first and second electrode portions 21 and 22. At this time, an AC power source having a predetermined amplitude and period may be applied to the first and second electrode units 21 and 22, or a power source having a predetermined amplitude and period may be applied by repeatedly applying the DC power source . Hereinafter, the self-alignment of the ultra-small LED element 40 by the electric field E formed by applying a predetermined power source to the first and second electrode portions 21 and 22 will be described in more detail.

4A is a perspective view of a pixel structure according to an embodiment of the present invention before a voltage is applied to the first and second electrode units. 4B is a schematic diagram of a pixel structure according to an embodiment of the present invention. 4C is a perspective view of a pixel structure according to an exemplary embodiment of the present invention, after voltage is applied to the first and second electrode units. 4D is a schematic diagram of a pixel structure according to an embodiment of the present invention.

The ultra miniature LED device 40 according to the embodiment of the present invention can be formed in a very small size of nano unit so that the ultra miniature LED device 40 can be physically or directly attached to the first and second electrode parts 21, There may be difficulty connecting. Referring to FIG. 4A, the ultra-small LED device 40 according to an exemplary embodiment of the present invention may be injected into the first and second electrode portions 21 and 22 in a solution state mixed with the solvent 50. At this time, when power is not supplied to the first and second electrode units 21 and 22, the ultra-small LED element 40 floats in the solution and flows only in the outer portions of the first and second electrode units 21 and 22 Or disposed adjacent to each other. In addition, when the ultra-small LED element 40 is formed into a cylindrical shape according to an embodiment, the ultra-small LED element 40 can be rotationally moved on the first and second electrode portions 21 and 22 by the shape characteristics, Accordingly, the miniature LED device 40 may not be connected to the first and second electrode units 21 and 22 at the same time by the self-aligning method.

Referring to FIGS. 2 and 4B, the first and second electrode units 21 and 22 according to the exemplary embodiment of the present invention can be supplied with different voltages, A predetermined electric field E may be formed between the electrodes 21 and 22. As described above, the first and second electrode units 21 and 22 may be provided with an AC power source or a DC power source having a predetermined voltage and period through the first drain electrode 613 and the power source wiring 630, A first electric field E ₁ of a radial shape corresponding to a potential difference between the first and second electrode portions 21 and 22 is formed between the first and second electrode portions 21 and 22 . At this time, the intensity of the first electric field E ₁ may be proportional to the potential difference between the first and second electrode units 21 and 22, and the first distance between the first and second electrode units 21 and 22 D ₁ ). The first difference distance D ₁ between the first and second electrode portions 21 and 22 is 1 μm or more and 7 μm or less and the voltage difference applied to the first and second electrode portions 21 and 22 is But the present disclosure is not limited thereto.

4C and 4D, when power is supplied to the first and second electrode units 21 and 22, the ultra-small LED device 40 according to an embodiment of the present invention includes the first and second electrode units 21 and 22, It can be self-aligned between 21 and 22, the first electric field first and second electrodes (21, 22) by induction of (E ₁₎ defined by the potential difference. The first electric field E ₁ in the radiation direction, that is, the radiation direction centering on the first electrode unit 21 can be formed by the potential difference between the first and second electrode units 21 and 22 , The charge can be asymmetrically induced in the ultra-small LED element 40 by the induction of the first electric field E ₁ . Accordingly, the ultra-small LED element 40 can be self-aligned between the first and second electrode portions 21, 22 along the direction of the first electric field E ₁ . At this time, the connection portions of the ultra-small LED elements 40, for example, the first and second electrode layers 410 and 420 may be disposed so as to be in contact with the first and second electrode portions 21 and 22 at the same time, Accordingly, the ultra miniature LED device 40 can be electrically connected to the first and second electrode units 21 and 22. The ultra-small LED element 40 according to one example is provided between the first and second electrode portions 21 and 22 by induction of an electric field E formed by a potential difference between the first and second electrode portions 21 and 22 As the intensity of the electric field E increases, the number of the ultra-small LED elements 40 connected to the first and second electrode units 21 and 22 can be increased. The intensity of the electric field E may be proportional to the potential difference between the first and second electrode units 21 and 22 and may be inversely proportional to the separation distance D ₁ between the first and second electrode units 21 and 22 can do.

Thereafter, although not shown, the first and second electrode portions 21 and 22, in which the ultra-miniaturized LED element 40 is substantially mounted to form each pixel region in which the ultra-small LED element 40 is substantially mounted, An insulation process for insulating the remaining region except the region may be performed. Accordingly, the pixel structure 1 including the plurality of first and second electrode portions 21 and 22 may include a plurality of pixel regions.

A display device including a plurality of ultra-small LED elements 40 is classified into a passive matrix type display device and an active matrix type display device according to a method of driving the ultra-small LED element 40. [ As an example, when the display device is sphere-shaped in an active matrix form, the pixel structure 1 includes a first transistor TFT1 as a driving transistor for controlling the amount of current supplied to the ultra-small LED element 40, And a second transistor (TFT2) as a switching transistor for transmitting a data voltage to the first transistor (TFT1). In recent years, an active matrix type display device which selects and lights every unit pixel from the viewpoints of resolution, contrast, and operation speed has been the mainstream, but the present invention is not limited thereto. Passive matrix type display devices, The electrode arrangement of the disclosure may be used.

As described above, the pixel structure 1 according to an embodiment of the present invention includes the nano-structure formed by using the electric field E radially formed between the first and second electrode portions 21 and 22, The micro LED element 40 is aligned and connected between the first and second electrode portions 21 and 22 so that the micro LED element 40 is connected to the first and second electrode portions 21 , 22) in a one-to-one correspondence. In addition, even if a conventional cylindrical LED element 40 is used, alignment between the LED element 40 and the first and second electrode portions 21 and 22 is maintained, thereby minimizing the defective rate of the pixel structure 1 can do. In addition, the ultra-small LED elements 40 can be intensively arranged and connected to a desired mounting region including the first and second electrode portions 21 and 22, which are different from each other

5A is a perspective view of a pixel structure according to another embodiment of the present invention. 5B is a cross-sectional view of the pixel structure taken along line B-B 'of the pixel structure shown in FIG. 5A. 5A and 5B, a pixel structure 1 according to another embodiment of the present invention includes a first electrode unit 21, a second-electrode unit 22- The second electrode unit 22 including the second electrode unit 22-2 and the first electrode unit 21 and the second electrode unit 22-1 and the second electrode unit 22-2, A plurality of very small LED elements 40 disposed between the electrode portions 22-2 and a solvent 50 in which a plurality of very small LED elements 40 are mixed. The description of the same configuration described in the above embodiment is omitted for the sake of convenience.

The second electrode unit 22 may include a second-first electrode unit 22-1 and a second-second electrode unit 22-2 that are spaced apart from each other. The 2-1 electrode unit 22-1 and the 2-2 electrode unit 22-2 are disposed on the interlayer insulating film 605 and are electrically connected to the ultra miniature LED device 40. [ to be. As one example, each of the second-first electrode portion 22-1 and the second-electrode portion 22-2 may be a semicircular shape extending along the circumferential direction about the first electrode portion 21 have.

Also, the second-1 electrode unit 22-1 and the second -2 electrode unit 22-2 according to an embodiment may be provided in a plurality, and the plurality of second-1 electrode units 22-1 And the second -2 electrode unit 22-2 may be spaced apart from each other with a predetermined gap therebetween at an upper portion of the interlayer insulating film 605. [ Also, the plurality of second-1 electrode units 22-1 according to an embodiment may be connected to each other using the first electrode line 220-1. 5B, the power wiring 630 may be electrically connected to each of the second-first electrode unit 22-1 and the second-electrode unit 22-2 through a through-hole, The power of the first voltage is supplied to the plurality of second-first electrode units 22-1, and the power of the second voltage is supplied to the plurality of second-second electrode units 22-2 . At this time, the magnitudes of the first voltage and the second voltage may be different.

In addition, the second-first electrode unit 22-1 and the second-electrode unit 22-2 according to an embodiment may be formed of one or more metal materials selected from the group consisting of aluminum, titanium, indium, gold, Or a transparent material selected from the group consisting of indium tin oxide (ITO), ZnO: Al, and CNT-conductive polymer composite. In the case where two or more kinds of substances are included in the second-first electrode portion 22-1 and the second-second electrode portion 22-2, the second-first electrode portion 22-1 and the second- The 2-2 electrode portion 22-2 may be formed by stacking two or more kinds of materials. As an example, the second-first electrode portion 22-1 and the second-second electrode portion 22-2 may include the same material as well as different materials.

FIG. 6A is a perspective view of a pixel structure according to another embodiment of the present invention before a voltage is applied to the first and second electrode units. FIG. 6B is a schematic diagram of a pixel structure according to another embodiment of the present invention. 6C is a perspective view of a pixel structure according to another embodiment of the present invention after a voltage is applied to the first and second electrode portions. 6D is a schematic diagram of a pixel structure according to another embodiment of the present invention.

4A to 4D, the pixel structure 1 according to an embodiment of the present invention includes an electric field E radially formed between the first and second electrode portions 21 and 22 The miniature LED device 40 of the nano unit size, which is independently manufactured, can be aligned and connected between the first and second electrode parts 21 and 22, which are different from each other. Therefore, when the first electric field E ₁ is radially formed between the first and second electrode portions 21 and 22 as shown in FIG. 4C, a gap is formed between the first and second electrode portions 21 and 22 The miniature LED device 40 may be aligned between the first and second electrode units 21 and 22 while the same voltage is applied to the plurality of second electrode units 22, A separate electric field E can not be formed between the first and second electrode portions 22 and 22. Thus, the ultra-small LED element 40 disposed between the plurality of second electrode portions 22 is disposed outside Or may be disposed adjacent to each other.

Referring to FIG. 6A, a first electrode unit 21 and a 2-1 electrode unit 22-1 (see FIG. 6A) are formed in a solution state in which a very small LED element 40 according to an embodiment of the present invention is mixed with a solvent 50 And the second -2 electrode unit 22-2. At this time, when power is not supplied to the first electrode unit 21, the 2-1 electrode unit 22-1 and the second -2 electrode unit 22-2, the ultra-small LED element 40 And may be disposed only on the outer portion of the first electrode portion 21 and the 2-1 electrode portion 22-1 and the second electrode portion 22-2, or adjacent to each other. Referring to FIG. 6B, power is applied to the first electrode unit 21, the second-first electrode unit 22-1, and the second-electrode unit 22-2 according to an embodiment of the present invention. The first electrode unit 21 and the second electrode unit 22-1, the first electrode unit 21 and the second electrode unit 22-2, and the second electrode unit 22-1, A predetermined electric field E may be formed between the electrode portion 22-1 and the second -2 electrode portion 22-2. For example, the first electrode unit 21, the second electrode unit 22-1, and the second electrode unit 22-2 may be provided with an AC power source The first electrode unit 21 and the second electrode unit 22-2 are provided between the first electrode unit 21 and the second electrode unit 22-1, 2) the first-first electric field according to the potential difference (E ₁₁₎ is comprising: a first electrode portion 21 and the 2-2 electrode portion 22-2 has a first electrode portion 21 is formed between the second -2 electric field E ₁₂ is formed in accordance with the potential difference between the first-second electrode unit 22-2 and the second-first electrode unit 22-2, A second electric field E ₂ may be formed according to a potential difference between the second-first electrode unit 22-1 and the second-second electrode unit 22-2.

Referring to FIGS. 6C and 6D, the ultra miniature LED device 40 according to an embodiment of the present invention includes a first 1-1 electric field (not shown) formed by a potential difference between the first and second electrode parts 21 and 22-1, Can be self-aligned between the first and second-electrode parts (21, 22-1) by induction of the first electrode (E ₁₁ ). According to an embodiment, when power having a predetermined voltage difference is supplied to the first and second -1 electrode units 21 and 22-1 as described above, the first and second -1 electrode units The first 1-1 electric field E ₁₁ may be formed between the first electrode unit 21 and the second-1 electrode unit 22-1 by a potential difference between the first electrode unit 21 and the second electrode unit 22-1. In this way, the first-first electric field (E ₁₁₎ can be asymmetric to the charge in a compact LED element 40 is induced by the induction of, a tiny LED element 40 is the first-first electric field (E ₁₁₎ And may be self-aligned between the first electrode portion 21 and the second electrode portion 22-1. At this time, the connecting portions of the ultra-small LED element 40, for example, the first and second electrode layers 410 and 420 are arranged to contact the first and second-electrode portions 21 and 22-1 simultaneously So that the ultra-small LED element 40 can be electrically connected to the first and second-electrode parts 21 and 22-1.

Further, the ultra-small LED element 40 is formed by the induction of the first-second electric field E ₁₂ formed by the potential difference between the first and second electrode portions 21 and 22-2, And can be self-aligned between the electrode portions 21 and 22-2. Formation of a first -2 electric field E ₁₂ by the first and second electrode portions 21 and 22-2 and. The matters related to the self-alignment of the ultra-small LED element 40 generated by asymmetrically inducing charge in the ultra-small LED element 40 according to the first-second electric field E ₁₂ are the first and second electrode parts 21 and 22-2 of the micro-LED device 40, description thereof will be omitted here.

According to one embodiment, as described above, the first-electric-field E ₁₁ generated by the potential difference between the first and second-electrode parts 21 and 22 - 1, the first and second electric- The first electric field E ₁₂ formed by the potential difference between the electrode portions 21 and 22-2 can be radially formed around the first electrode portion 21. Since the voltages of the power source applied to the second-first electrode unit 22-1 and the second-electrode unit 22-2 are different from each other, the first and second-electrode units 21 and 22-1, The first separation distance D ₁₁ between the first and second electrode portions 21 and 22-2 is equal to the second separation distance D ₁₂ between the first and second electrode portions 21 and 22-2, E ₁₁ ) and the first electric field E ₁₂ may be different from each other. Therefore, the first and second electric fields E ₁₁ (E ₁₁ and E ₁₂ ) formed between the first electrode unit 21 and the second-first electrode unit 22 - 1 and the second- , E ₁₂ may be formed to be uniformly formed, the first separation distances D ₁₁ and the second separation distances D ₁₂ may be formed differently. For example, when the first voltage of the power source applied to the second-electrode unit 22-1 is greater than the second voltage applied to the second-electrode unit 22-2, The distance D ₁₁ may be greater than the first distance D ₁₂ so that the first electric field E ₁ , which is the sum of the first and second electric fields E ₁₁ and E ₁₂ , Can be uniformly formed. However, the present invention is not limited to this, and the 1-1 separation distance D ₁₁ and the 1-2 separation distance D ₁₂ may be formed identically. For example, as shown in FIG. 3, when the length T of the ultra-small LED element 40 is in the range of 2 μm to 5 μm, the first separation distance D ₁₁ and the second separation distance D ₁₂ may be 1 μm or more and 7 μm or less and the first electrode unit 21 and the second electrode unit 22-1 and the first electrode unit 21 and the second electrode unit 22-2 The applied voltage difference may be 10 V or more and 50 V or less.

Further, when the ultra-small LED element 40 is disposed between the second-first and second-electrode parts 22-1 and 22-2, the ultra-small LED element 40 is arranged between the second- -2 electrode portion (22-1, 22-2), a second electric field (E _2), the 2-1 electrode portion (22-1) or the 2-2 electrode portion (22-by the induction of which is formed by the potential difference 2). According to one embodiment, when a voltage higher than that of the second-second electrode unit 22-2 is applied to the second-first electrode unit 22-1 and no voltage is applied to the first electrode unit 21, A first electric field E ₁₁ is formed between the first electrode unit 21 and the second electrode unit 22-1 and the first electrode unit 21 and the second electrode unit 22 -2), the first-second electrical field (E ₁₂₎ a second electric field towards the second-second electrode portion 22-2 is formed from the, the 2-1 electrode portion 22-1 between (E ₂₎ Can be formed. At this time, the first-first electric field (E ₁₁₎ is a first-second electrical field (E ₁₂₎ greater than, the first-second electrical field (E ₁₂₎ may be greater than the second electric field (E _2).

For example, when the ultra-small LED element 40 is disposed between the second-first electrode portion 22-1 and the second-second electrode portion 22-2, the second-first electrode portion 22-1 The electric charge can be asymmetrically induced in the ultra-small LED element 40 by the induction of the second electric field E ₂ formed between the first and second electrode portions 22-2 and 22-2. At this time, the ultra-small LED element 40 disposed between the 2-1 electrode portion and the 2-2 electrode portions 22-1 and 22-2 is electrically connected to the second electric field E ₂ along the direction of the second electric field E ₂ And can be moved toward the electrode portion 22-2. Subsequently, the micro LED element 40 is electrically connected to the first electrode portion and the second electrode portion by the first and second electric field E ₁₂ formed by the first and second electrode portions 21 and 22-2. Can be self-aligned between the two electrode portions 21 and 22-2.

As described above, the pixel structure 1 according to the embodiment of the present invention includes the second-first electrode portion 22-1 and the second-second electrode portion 22-2 to which different voltages are applied So that all the ultra-small LED elements 40 disposed in the pixels can be separated from each other by the first electrode portion 21 and the second electrode portion 2-1 and the second electrode portion 2-2, And can be aligned and connected between the electrode portions 22-1 and 22-2.

Fig. 7 is a conceptual view of the display device 1000 according to the embodiment.

7, a display device 1000 includes a plurality of pixel structures 1 according to the above-described embodiments, and a driving circuit connected to the plurality of pixel structures 1.

The plurality of pixel structures 1 may be disposed in the display area DA of the display device 1000. [ The driving circuit may be disposed in a non-display area disposed on the outer periphery of the display area DA of the display apparatus 1000. [ The driving circuit includes a data driving circuit (7) and a gate driving circuit (8).

The length of one side of the pixel structure 1 may be 600 μm or less. When the pixel structure 1 constitutes a subpixel, the length of one side of the pixel structure 1 may be 200 μm or less. One side of the pixel structure 1 may be a short side of the pixel structure 1. However, the size of the pixel structure 1 is not limited thereto, and may be changed according to the size of the display device 1000 and the required number of pixels.

The data driving circuit 7 includes a plurality of source drive ICs to drive the data lines DL. The gate drive circuit 8 includes at least one gate drive IC to supply a scan pulse to the gate lines GL.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. I will understand. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (18)

A base substrate;
A first electrode unit disposed on the base substrate;
A second electrode part having a circular shape extending in a circumferential direction about the first electrode part; And
A plurality of LED elements connected to the first electrode portion and the second electrode portion and arranged radially along respective different directions;
And a pixel structure. The method according to claim 1,
Wherein one end of each of the plurality of LED elements is positioned on the first electrode portion and the other end is positioned on the second electrode portion. 3. The method of claim 2,
Wherein one end of each of the plurality of LED elements is directly connected to the first electrode portion and the other end is directly connected to the second electrode portion. The method according to claim 1,
Wherein two LED elements disposed adjacent to each other among the plurality of LED elements are arranged in a first direction and a second direction intersecting the first direction, the first direction and the second direction being acute angles, Structure. The method according to claim 1,
Wherein imaginary lines extending from different directions in which each of the plurality of LED elements is disposed meet at a virtual contact point and the virtual contact point is located within the first electrode portion. The method according to claim 1,
And the second electrode portion is annularly provided with a closed curve. The method according to claim 6,
Wherein the first electrode portion has a circular shape and is located at the center of the second electrode portion. The method according to claim 1,
A driving transistor electrically connected to the first electrode unit; And
A power supply line electrically connected to the second electrode unit;
≪ / RTI > The method according to claim 1,
Wherein the first electrode portion and the second electrode portion are plurally provided, and further comprising an electrode line connecting the plurality of second electrode portions. The method according to claim 1,
Wherein a distance between the first electrode portion and the second electrode portion is 1 占 퐉 or more and 7 占 퐉 or less. The method according to claim 1,
The second electrode unit includes a first sub-electrode unit and a second sub-electrode unit having a semicircular shape,
Wherein the first sub-electrode portion and the second sub-electrode portion are separately arranged to be spaced apart from each other. 12. The method of claim 11,
A driving transistor electrically connected to the first electrode unit; And
A power supply line electrically connected to the first sub-electrode unit and the second sub-electrode unit, respectively;
≪ / RTI > 12. The method of claim 11,
Wherein the first electrode unit and the second electrode unit are provided in plurality,
A first electrode line connecting the plurality of first sub-electrode units; And
A second electrode line connecting the plurality of second sub-electrode units;
≪ / RTI > 14. The method of claim 13,
Wherein a first spacing distance between the first sub-electrode portion and the first electrode portion and a second spacing distance between the second sub-electrode portion and the first electrode portion are different from each other. 15. The method of claim 14,
Wherein the first spacing distance and the second spacing distance are 1 占 퐉 or more and 7 占 퐉 or less. 12. The method of claim 11,
Wherein one end of each of the plurality of LED elements is located on the first electrode portion and the other end is located on the first sub-electrode portion or the second sub-electrode portion. 17. The method of claim 16,
Wherein one end of each of the plurality of LED elements is directly connected to the first electrode portion and the other end is directly connected to the first sub-electrode portion or the second sub-electrode portion. 17. A pixel structure according to any one of claims 1 to 17,
And a driving circuit connected to the pixel structure.

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