Stamp for transferring LED, method for transferring LED using stamp, and display device

Abstract

Embodiments disclose a stamp for transferring a light emitting element, a method of transferring a light emitting element using the same, and a display device. The stamp includes: a stamp substrate; a non-overlapping stamp pattern region defined on the stamp substrate, and an overlapping stamp pattern region adjacent to an outer periphery of the non-overlapping stamp pattern region; a plurality of first pickup transfer patterns disposed in the non-overlapping stamp pattern area; and a plurality of second pickup transfer patterns disposed in different rows in the overlapping stamp pattern region with the non-overlapping stamp pattern region therebetween.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority and the benefit of Korean Patent Application No. 10 - 2023 - 0188362, filed on December 21, 2023, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a display device, and more particularly to a stamp for transferring light - emitting elements (LEDs), a method of transferring light - emitting elements using the stamp, and a display device. Background Art

[0004] Technological advancements have led to the development of display devices incorporating self - emitting elements. Display devices incorporating self - emitting elements can be an organic light - emitting display device including an organic material as a light - emitting layer and a micro - LED display device using micro - light - emitting elements.

[0005] Micro - light - emitting elements are extremely small light - emitting elements having a size of several tens of μm or less. Using such micro - light - emitting elements as pixels enables miniaturization of the device and reduces the weight of the device. However, the size of the light - emitting elements is very small and a large number of light - emitting elements must be formed, which results in high manufacturing costs and time consumption. Summary of the Invention

[0006] To manufacture a display device incorporating micro - light - emitting elements, micro - light - emitting elements can be crystallized on a substrate such as sapphire or silicon, and then the crystallized micro - light - emitting elements can be transferred to a substrate having a driving circuit. In the process of transferring micro - light - emitting elements, a method of stamping a plurality of micro - light - emitting elements that have been picked up on a stamp can be used to stamp a plurality of micro - light - emitting elements on a panel substrate formed with a driving circuit.

[0007] However, due to differences in the transfer process capabilities of the respective transfer regions of the stamp, stamp ghosting appears at the stamp boundary portion or on the stamp surface.

[0008] Therefore, the stamp ghosting caused by repeatedly transferring a plurality of micro - light - emitting elements on a substrate using a stamp can be visible, which increases the defect rate of the micro - light - emitting elements and thus reduces the yield of the display device.

[0009] To solve the above problems, an object of the present application is to provide a stamp for transferring light - emitting elements, a method of transferring light - emitting elements using the stamp, and a display device that can improve the visibility of stamp ghosting in a panel, reduce the defect rate of micro - LED transfer using a stamp, and thus improve the yield.

[0010] The problems to be solved by the present application are not limited to those mentioned above, and those skilled in the art will clearly understand other problems not mentioned from the following description.

[0011] A stamper for transferring light-emitting elements according to an embodiment of the present application includes: a stamper substrate; a non-overlapping stamper pattern area defined on the stamper substrate, and an overlapping stamper pattern area adjacent to the outer periphery of the non-overlapping stamper pattern area; a plurality of first pick-up transfer patterns provided in the non-overlapping stamper pattern area; and a plurality of second pick-up transfer patterns provided in different rows in the overlapping stamper pattern area with the non-overlapping stamper pattern area therebetween.

[0012] A method of transferring light-emitting elements using a stamper, the method including: preparing a substrate having a plurality of transfer areas divided into non-overlapping transfer areas and overlapping transfer areas; preparing a stamper including a plurality of first pick-up transfer patterns configured to transfer a plurality of first light-emitting elements to the non-overlapping transfer areas of the substrate, and a plurality of second pick-up transfer patterns configured to transfer a plurality of second light-emitting elements to the overlapping transfer areas of the substrate; and performing a plurality of transfer processes using the stamper to transfer the plurality of first light-emitting elements picked up on the plurality of first pick-up transfer patterns to the non-overlapping transfer areas of the substrate, and transfer the plurality of second light-emitting elements picked up on the plurality of second pick-up transfer patterns to the overlapping transfer areas.

[0013] A display device includes: a substrate having a plurality of transfer areas; a non-overlapping transfer area and an overlapping transfer area defined in each of the plurality of transfer areas; a plurality of bank patterns provided in the non-overlapping transfer area and the overlapping transfer area of the substrate; a plurality of first electrodes provided on the plurality of bank patterns; a plurality of light-emitting elements provided on the plurality of first electrodes; and a second electrode provided on the plurality of light-emitting elements, wherein the light-emitting elements provided in the overlapping transfer area include light-emitting elements overlapping the bank patterns on the first electrodes and light-emitting elements having a portion not overlapping the bank patterns on the first electrodes.

[0014] According to the present application, when transferring a plurality of light-emitting elements using a stamper, by defining an overlapping transfer area in a plurality of transfer areas defined on a substrate and offsetting process capability differences between stamper transfer processes in the overlapping transfer area, the visibility of stamper ghosting can be improved.

[0015] According to the present application, when using a stamp to transfer a plurality of light-emitting elements, process capability differences between stamp transfer processes in an overlapping transfer region can be minimized to reduce the stamp ghost defect rate during panel image inspections such as AP inspections and module inspections, thereby improving the yield of the manufacturing process.

[0016] The effects of the present application are not limited to the effects mentioned above, and those skilled in the art will clearly understand other effects not mentioned from the following description and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By describing exemplary embodiments of the present disclosure in detail with reference to the accompanying drawings, the above and other objects, features, and advantages of the present disclosure will become more apparent to those of ordinary skill in the art. In the drawings:

[0018] Figure 1 is a view illustrating a display device according to an embodiment of the present application;

[0019] Figure 2 is Figure 1 an enlarged view of region A of

[0020] Figure 3 is a view illustrating a partial region of a pixel;

[0021] Figure 4 is Figure 3 a cross-sectional view taken along line I-I' in

[0022] Figure 5 is Figure 3 a cross-sectional view taken along line II-II' in

[0023] Figure 6 is Figure 5 an enlarged view of region B of

[0024] Figure 7A and Figure 7B are perspective views illustrating a process of picking up and transferring light-emitting elements using a light-emitting element transfer stamp according to an embodiment of the present application;

[0025] Figure 8A and Figure 8B are perspective views illustrating a first transfer process and a second transfer process using a light-emitting element transfer stamp according to an embodiment of the present application;

[0026] Figure 9 is a plan view illustrating a light-emitting element transfer stamp according to an embodiment of the present application;

[0027] Figure 10 is Figure 9 a cross-sectional view taken along line III-III' in

[0028] Figure 11 is a plan view of a substrate having a transfer region defined thereon according to an embodiment of the present application;

[0029] Figure 12 is Figure 11 an enlarged view of region C in

[0030] Figure 13 is a cross-sectional view taken along line IV-IV in Figure 11 ;

[0031] Figure 14 is a cross-sectional view taken along line V-V' in Figure 13 ;

[0032] Figure 15 is a cross-sectional view taken along line VI-VI' in Figure 13 ; and

[0033] Figure 16A and Figure 16B are diagrams showing whether stamper ghosting is visible during the process of transferring a plurality of light-emitting elements using a stamper according to an embodiment of the present application when an overlapping transfer region is employed and when an overlapping transfer region is not employed. DETAILED DESCRIPTION

[0034] The advantages and features of the present application and the methods for achieving these advantages and features will become apparent from the embodiments described with reference to the accompanying drawings. However, the present application is not limited to the following embodiments, but may be implemented in different forms; on the contrary, the present embodiments are provided to make the disclosure of the present application complete and enable those skilled in the art to fully understand the scope of the present application, and the present application is only defined within the scope of the appended claims.

[0035] The shapes, sizes, ratios, angles, numbers, etc. of the elements shown in the drawings for illustrating the embodiments of the present application are merely illustrative and are not intended to be restrictive. In addition, when describing the present application, detailed descriptions of well-known technologies may be omitted so as not to obscure the essence of the present disclosure.

[0036] Terms such as "comprising", "having", and "constituting" used herein generally intend to allow the addition of other components, unless these terms are used with the term "only". Unless otherwise specifically stated, the reference to a component of a singular noun includes the plural of that noun.

[0037] When interpreting a component, even if not explicitly stated, it is also interpreted as including a margin of error.

[0038] When describing a positional relationship, for example, if the positional relationship between two components is described as "above", "over", "under", and "adjacent to", one or more other components may be provided between the two components unless "immediately" or "directly" is used.

[0039] When referring to an element or layer being on another element or layer, this includes any intervening layer or other element directly on top of or between the other elements.

[0040] In addition, first, second, etc. are used to describe various components, but these components are not limited by these terms. These terms are only used to distinguish one component from another. Thus, within the technical spirit of the present disclosure, the first component mentioned below may be the second component.

[0041] The same reference numerals may refer to the same components throughout the application.

[0042] The dimensions and thicknesses of each structure shown in the drawings are shown for illustrative purposes only and need not be limited to the dimensions and thicknesses of the structures shown herein.

[0043] Each of the features of the various embodiments described herein may be combined or combined with each other, in whole or in part, and may be interlocked and operated in various ways technically, and each of these embodiments may be performed independently or in combination with each other.

[0044] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the drawings.

[0045] A display device according to an embodiment of the present application includes: a display panel having a display area or screen on which an image is displayed; and a pixel driving circuit that drives pixels of the display panel. The display area includes a pixel area in which pixels are arranged. The pixel area includes a plurality of light-emitting areas. A light-emitting element is provided in each light-emitting area. The pixel driving circuit may be built into the display panel.

[0046] Figure 1 is a diagram illustrating a display device according to an embodiment of the present application.

[0047] Figure 2 is Figure 1 an enlarged view of region A in Figure 3 is a diagram illustrating a partial area of a pixel.

[0048] Refer to Figure 1 and Figure 2, the display device 10 according to an embodiment of the present application includes a display panel on which an input image is visually reproduced. The display panel may include a display area 12 for displaying an image and a non-display area 14 for not displaying an image. In the non-display area 14, various wirings and driving circuits may be installed, and pad portions PAD for connecting integrated circuits, printed circuits, etc. may be provided.

[0049] The plurality of light-emitting elements 100 provided in the display area 12 to form pixels PXL may be micro inorganic light-emitting elements. The inorganic light-emitting elements may be grown on a silicon wafer and then attached to the display panel through a transfer process.

[0050] The transfer process of the light-emitting elements 100 may be performed for each pre-divided area. Although Figure 1 FIG. illustrates that the display area 12 is divided into twelve transfer areas 16, but the size of the transfer area or the number of divisions of the transfer area is not limited thereto. The transfer process may be performed sequentially or simultaneously in the first transfer area 16 to the twelfth transfer area 16. The blue light-emitting elements 100, green light-emitting elements 100, and red light-emitting elements 100 may be sequentially transferred to the transfer area 16.

[0051] In the non-display area 14, a data driving circuit or a gate driving circuit may be provided, and wirings for providing control signals for controlling the driving circuits may be provided. Here, the control signals may include various timing signals, and the control signals may be received through the pad portions PAD. The various timing signals include a clock signal, an input data enable signal, and a synchronization signal.

[0052] The pixel PXL may be driven by a pixel driving circuit. The pixel driving circuit may receive a driving voltage, an image signal (digital signal), a synchronization signal synchronized with the image signal, etc., and may output an anode voltage and a cathode voltage of the light-emitting element 100 to drive a plurality of pixels. The driving voltage may be a high-potential voltage EVDD. The cathode voltage may be a low-potential voltage EVSS commonly applied to the pixels. The anode voltage may be a voltage corresponding to the pixel data value of the image signal. The pixel driving circuit may be provided in the non-display area 14 or may be provided below the display area 12.

[0053] Each pixel PXL may include a plurality of sub-pixels having different colors. For example, the plurality of pixels may include a red sub-pixel provided with a light-emitting element 100 that emits light of a red wavelength, a green sub-pixel provided with a light-emitting element 100 that emits light of a green wavelength, and a blue sub-pixel provided with a light-emitting element 100 that emits light of a blue wavelength. The plurality of pixels may further include a white sub-pixel.

[0054] Referring to Figure 2 and Figure 3, a plurality of pixels PXL may be continuously arranged along a first direction (X-axis direction) and a second direction (Y-axis direction). A plurality of sub-pixels of the same color may be provided within the pixels of the display area 12. For example, each of the plurality of sub-pixels may include: a first red sub-pixel in which a first red light-emitting element 100R that emits light of a red wavelength is provided; a second red sub-pixel in which a second red light-emitting element 100R' that emits light of a red wavelength is provided; a first green sub-pixel in which a first green light-emitting element 100G that emits light of a green wavelength is provided; a second green sub-pixel in which a second green light-emitting element 100G' that emits light of a green wavelength is provided; a first blue sub-pixel in which a first blue light-emitting element 100B that emits light of a blue wavelength is provided; and a second blue sub-pixel in which a second blue light-emitting element 100B' that emits light of a blue wavelength is provided. The first red light-emitting element 100R, the first green light-emitting element 100G, and the first blue light-emitting element 100B may be regarded as main light-emitting elements. The second red light-emitting element 100R', the second green light-emitting element 100G', and the second blue light-emitting element 100B' may be regarded as sub-light-emitting elements.

[0055] A sub-pixel may include at least one or more light-emitting elements, and in the case where one light-emitting element becomes defective, the brightness of another light-emitting element may be increased to adjust the brightness of the sub-pixel. However, the embodiment is not necessarily limited thereto, and a sub-pixel may include only one light-emitting element.

[0056] A plurality of first electrodes 102 may be respectively provided on the lower portions of the light-emitting elements 100, and the plurality of first electrodes 102 may be selectively connected to a plurality of signal wirings TL1 to TL6 through the extension portions 102a. A high-potential voltage may be applied to the pixel driving circuit through the signal wirings TL1 to TL6. During the electrode patterning process, the signal wirings TL1 to TL6 and the first electrodes 102 may be formed as an integrated electrode pattern.

[0057] For example, the first signal wiring TL1 may be connected to the anode electrode of the first red sub-pixel, and the second signal wiring TL2 may be connected to the anode electrode of the second red sub-pixel. The third signal wiring TL3 may be connected to the anode electrode of the first green sub-pixel, and the fourth signal wiring TL4 may be connected to the anode electrode of the second green sub-pixel. The fifth signal wiring TL5 may be connected to the anode electrode of the first blue sub-pixel, and the sixth signal wiring TL6 may be connected to the anode electrode of the second blue sub-pixel. When a sub-pixel includes only one light-emitting element, the number of the signal wirings TL may be reduced by half.

[0058] The second electrode 104 may be a cathode electrode provided for each row and applying a cathode voltage to the light-emitting elements 100 arranged continuously in the first direction (X-axis direction). A plurality of second electrodes 104 may be separated from each other in the second direction (Y-axis direction). The plurality of second electrodes 104 may be connected to the cathode voltage through the contact electrodes 106. Each of the plurality of second electrodes 104 may be electrically connected to the contact electrode 106. However, the embodiment is not necessarily limited thereto, and the second electrode 104 may be configured as one electrode layer without being divided into a plurality of electrodes, and the second electrode 104 may be used as a common electrode.

[0059] Figure 4 is a cross-sectional view taken along Figure 3 line I-I' in Figure 5 is a cross-sectional view taken along Figure 3 line II-II' in Figure 6 is Figure 5 an enlarged view of region B in

[0060] Referring to Figures 4 to 6 , a display device according to an embodiment of the present application includes: a plurality of first electrodes 102 and contact electrodes 106 provided on a substrate 200, a plurality of light-emitting elements 100 provided on the plurality of first electrodes 102, and a first optical layer 136 provided between the plurality of light-emitting elements 100. The display device further includes a second electrode 104 provided on the first optical layer 136.

[0061] The substrate 200 may be made of flexible plastic. For example, the substrate 200 may be manufactured as a single-layer substrate or a multi-layer substrate of a material selected from, but not limited to, polyimide, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyethersulfone, polyarylate, polysulfone, and cycloolefin copolymer. For example, the substrate 200 may be a ceramic substrate or a glass substrate.

[0062] The pixel driving circuit 201 may be provided in the display area 12 on the substrate 200. The pixel driving circuit 201 may include a plurality of thin film transistors using amorphous silicon semiconductors, polysilicon semiconductors, or oxide semiconductors.

[0063] The pixel driving circuit 201 may include at least one driving thin film transistor, at least one switching thin film transistor, and at least one storage capacitor. When the pixel driving circuit 201 includes a plurality of thin film transistors, it may be formed on the substrate 200 through a thin film transistor (TFT) manufacturing process. In an embodiment, the pixel driving circuit 201 may be a collective term for a plurality of thin film transistors electrically connected to the light-emitting element 100.

[0064] The pixel driving circuit 201 can be a driver fabricated using a metal-oxide-semiconductor field-effect transistor (MOSFET) manufacturing process on a single-crystalline semiconductor substrate 200. The driver can include a plurality of pixel driving circuits for driving a plurality of sub-pixels. When the pixel driving circuit 201 is implemented as a driver, an adhesive layer can be provided on the substrate 200, and then the driver can be mounted on the adhesive layer through a transfer process.

[0065] A buffer layer 202 covering the pixel driving circuit 201 can be provided on the substrate 200. The buffer layer 202 can be made of an organic insulating material, for example, photosensitive acrylic or photosensitive polyimide, but is not limited thereto.

[0066] An insulating layer 204 can be provided on the buffer layer 202. The insulating layer 204 can be made of an organic insulating material, for example, photosensitive acrylic or photosensitive polyimide, but is not limited thereto. Connection wirings RT1 and RT2 can be provided on the buffer layer 202. The connection wirings RT1 and RT2 can be connected as corresponding signal wirings TL1 to TL6, or can be connected to the signal wirings TL1 to TL6. The connection wirings RT1 and RT2 can include a plurality of wiring patterns provided in different layers with one or more insulating layers interposed therebetween. The wiring patterns provided in different layers can be electrically connected through contact holes penetrating the insulating layer.

[0067] A plurality of bank patterns 112 can be provided on the insulating layer 204. At least one light-emitting element 100 can be provided on each bank pattern 112.

[0068] The bank pattern 112 can be formed of an organic insulating material such as photosensitive acrylic or photosensitive polyimide, but is not limited thereto. During the transfer process of the light-emitting element 100, the bank pattern 112 can guide the position where the light-emitting element 100 is to be attached. The bank pattern 112 can be omitted.

[0069] A solder pattern 118 can be provided on the first electrode 102. The solder pattern 118 can be made of indium (In), tin (Sn), or an alloy thereof, but is not limited thereto.

[0070] A plurality of light-emitting elements 100 can be mounted on the corresponding solder patterns 118. One pixel can include light-emitting elements 100 of three colors. For example, the light-emitting element 100 can include a red light-emitting element, a green light-emitting element, or a blue light-emitting element. Two light-emitting elements can be mounted in each sub-pixel.

[0071] The first optical layer 136 may cover the plurality of light-emitting elements 100 and the plurality of bank patterns 112. Accordingly, the first optical layer 136 may cover between the plurality of light-emitting elements 100 and between the plurality of bank patterns 112. The first optical layer 136 may extend in a first direction X and may be separated in a second direction Y and separated between pixel rows.

[0072] The first optical layer 136 may include an organic insulating material in which fine metal particles such as titanium dioxide particles are dispersed. Light emitted from the plurality of light-emitting elements 100 may be scattered by the fine metal particles dispersed in the first optical layer 136 and exit to the outside.

[0073] A second electrode 104 may be provided on the plurality of light-emitting elements 100. The second electrode 104 may be commonly connected to the plurality of pixels PXL. The second electrode 104 may be a thin electrode through which light can pass. The second electrode 104 may be made of a transparent electrode material such as indium tin oxide (ITO), but is not necessarily limited thereto.

[0074] The second electrode 104 may extend in a first direction (X-axis direction) and may be separated in a second direction (Y-axis direction). In a plane, each of the plurality of second electrodes 104 may overlap the first optical layer 136 and may cover the plane outside the first optical layer 136.

[0075] The second optical layer 127 may be an organic insulating material on the second electrode 104. The second optical layer 127 may include the same material as the first optical layer 136 (e.g., silicone). However, embodiments are not necessarily limited thereto, and the first optical layer 136 and the second optical layer 127 may be formed of the same material or different materials.

[0076] The second optical layer 127 may cover a portion above the second electrode 104. That is, the first optical layer 136 and the second optical layer 127 may be used as a planarization layer. As a result, since there are no steps in the plane on which the black matrix 128 is formed, the pattern of the black matrix 128 on the second electrode 104 and the second optical layer 127 can be easily formed. However, embodiments are not necessarily limited thereto, and the top surfaces of the second optical layer 127 and the second electrode 104 may have different heights.

[0077] The black matrix 128 may be an organic insulating material to which a black pigment is added. The second electrode 104 may be in contact with the contact electrode 106 below the black matrix 128. Transmission holes 154 through which light emitted from the light-emitting elements 100 exits to the outside may be formed between the patterns of the black matrix 128. The problem of light mixing emitted from adjacent light-emitting elements 100 due to the first optical layer 136 can be improved by the black matrix 128.

[0078] The cover layer 156 may be an organic insulating material that covers the black matrix 128 and the second electrode 104. The contact electrode 106 may be electrically connected to the first connection wiring RT1 disposed thereunder, and the first connection wiring RT1 may be connected to the pixel driving circuit 201. Accordingly, the cathode voltage may be applied to the second electrode 104 through the contact electrode 106. The first electrode 102 may be electrically connected to the second connection wiring RT2. This will be discussed later.

[0079] The contact electrode 106 and the signal wirings TL1 to TL6 may be disposed on the same plane. The pixel driving circuit 201 may be disposed under the contact electrode 106 and the signal wirings TL1 to TL6. When the pixel driving circuit 201 is a driver, a plurality of drivers may be provided in the display panel.

[0080] The passivation layer 120 may expose the contact electrode 106 such that the contact electrode 106 and the second electrode 104 are electrically connected to each other. In addition, the passivation layer 120 may insulate the signal wirings TL2 to TL5 from the second electrode 104.

[0081] Referring Figure 6 , the extension portion 102a of the first electrode 102 may extend to one side 150 of the bank pattern 112 and be disposed on the insulating layer 204, and may be electrically connected to the connection wiring RT2.

[0082] The first electrode 102, the extension portion 102a, the signal wiring TL, and / or the connection wirings RT1 and RT2 may include a single layer or multiple layers of metals selected from titanium (Ti), molybdenum (Mo), and aluminum (Al).

[0083] The first layer ML1 and the third layer ML3 may include titanium (Ti) or molybdenum (Mo). The second layer ML2 may include aluminum (Al). The fourth layer ML4 may include a transparent conductive oxide layer such as indium tin oxide (ITO) or indium zinc oxide (IZO) that has good adhesion, corrosion resistance, and acid resistance to the solder pattern 118.

[0084] The first layer ML1, the second layer ML2, the third layer ML3, and the fourth layer ML4 may be sequentially deposited and then patterned by performing a photolithography process and an etching process.

[0085] The passivation layer 120 may include an open hole 120a that is disposed on the first electrode 102 and the signal wiring TL and exposes the solder pattern 118.

[0086] The light-emitting element 10 may include a first-conductive-type semiconductor layer 140, an active layer 142 disposed on the first-conductive-type semiconductor layer 140, and a second-conductive-type semiconductor layer 144 disposed on the active layer 142. The first driving electrode 146 may be disposed on the lower portion of the first-conductive-type semiconductor layer 140 and the second driving electrode 148 may be disposed on the upper portion of the second-conductive-type semiconductor layer 144.

[0087] The light-emitting element 100 may be formed on a silicon wafer by using a method such as metalorganic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), hydride vapor phase epitaxy (HVPE), or sputtering.

[0088] The first-conductive-type semiconductor layer 140 may be implemented with a compound semiconductor such as a group III-V or II-VI compound semiconductor, and may be doped with a first dopant. The first-conductive-type semiconductor layer 140 may be formed of one or more of semiconductor materials having an empirical formula of Al x1 In y1 Ga (1-x1-y1) N (0 ≤ x1 ≤ 1, 0 ≤ y1 ≤ 1, 0 ≤ x1 + y1 ≤ 1), InAlGaN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP, but is not limited thereto. When the first dopant is an n-type dopant such as Si, Ge, Sn, Se, or Te, the first-conductive-type semiconductor layer 140 may be an n-type nitride semiconductor layer. However, when the first dopant is a p-type dopant, the first-conductive-type semiconductor layer 140 may be a p-type nitride semiconductor layer.

[0089] The active layer 142 is a layer where electrons (or holes) injected through the first-conductive-type semiconductor layer 140 and holes (or electrons) injected through the second-conductive-type semiconductor layer 144 meet. When electrons and holes recombine, the active layer 142 may transition to a lower energy level and may generate light having a corresponding wavelength.

[0090] The active layer 142 may have any one of a single-well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, or a quantum wire structure, but the structure of the active layer 142 is not limited thereto. The active layer 142 may generate light in the visible band. For example, the active layer 142 may output light in any one of the blue, green, and red bands.

[0091] The second-conductivity-type semiconductor layer 144 may be disposed on the active layer 142. The second-conductivity-type semiconductor layer 144 may be implemented with a compound semiconductor such as a group III-V or II-VI compound, and the second-conductivity-type semiconductor layer 144 may be doped with a second dopant. The second-conductive semiconductor layer 144 may be formed of a semiconductor material selected from those having the empirical formula In x2 Al y2 Ga 1-x2-y2 N (0 ≤ x2 ≤ 1, 0 ≤ y2 ≤ 1, 0 ≤ x2 + y2 ≤ 1) or materials such as AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, the second-conductivity-type semiconductor layer 144 doped with the second dopant may be a p-type nitride semiconductor layer. When the second dopant is an n-type dopant, the second-conductivity-type semiconductor layer 144 may be an n-type nitride semiconductor layer.

[0092] Although in the embodiments the light-emitting element has been described as a vertical structure having driving electrodes 146 and 148 disposed on the upper and lower portions of the light-emitting structure, in addition to the vertical structure, the light-emitting element may also have a lateral structure or a flip-chip structure.

[0093] Hereinafter, a process of transferring a plurality of light-emitting elements constituting a display device to a substrate using a stamper for transferring a light-emitting element according to an embodiment of the present application will be described with reference to Figure 7A and Figure 7B FIGs.

[0094] Figure 7A and Figure 7B are perspective views illustrating a process of picking up and transferring a light-emitting element using a light-emitting element transfer stamper according to an embodiment of the present application.

[0095] Referring to Figure 7A and Figure 7B , in order to transfer a plurality of light-emitting elements constituting a display device, a growth substrate 300 having a plurality of light-emitting elements 100, a light-emitting element transfer stamper 400 for picking up and transferring the plurality of light-emitting elements 100, and a substrate 200 on which the plurality of light-emitting elements 100 are transferred to form a display panel may be provided.

[0096] The growth substrate 300 can be used as a substrate for growing the light-emitting element 100, which is an LED chip, and can be made of silicon (Si), sapphire (Al2O3), silicon carbide (SiC), gallium arsenide (GaAs), gallium nitride (GaN), gallium phosphide (GaP), indium phosphide (InP), zinc oxide (ZnO), spinel (MgAl2O4), magnesium oxide (MgO), lithium metaaluminate (LiAlO2), aluminum nitride (AlN), and lithium gallate (LiGaO2), but is not limited thereto.

[0097] On the growth substrate 300, a plurality of micro light-emitting elements 100 can be grown.

[0098] Each light-emitting element 100 is a semiconductor device that emits light energy of various wavelengths by applying an electrical signal using the characteristics of a compound semiconductor. The light-emitting element 100 can be set to have a thickness as small as a few micrometers.

[0099] A plurality of light-emitting elements 100 are arranged side by side in one direction on the growth substrate 300. The interval between adjacent light-emitting elements 100 is set to the minimum interval possible in the process. That is, in order to reduce the manufacturing cost of the growth substrate 300, it is desirable to integrate as many light-emitting elements 100 as possible in a smaller growth substrate 300.

[0100] The light-emitting element transfer stamper 400 serves as a transfer device for transferring a plurality of light-emitting elements 100 from the growth substrate 300 to the substrate 200. The light-emitting element transfer stamper 400 selectively picks up the light-emitting elements 100 from the growth substrate 300. The light-emitting element transfer stamper 400 selectively picks up the light-emitting elements 100 at predetermined positions and transfers them to the corresponding pixels on the substrate 200.

[0101] The substrate 200 is a substrate constituting a display device and has a plurality of pixels arranged thereon. The area where the plurality of pixels are arranged can be defined as an effective area. At least one light-emitting element 100 is finally assigned to each pixel. Signal wirings and electrodes for applying a driving signal to the light-emitting element 100 can be arranged on the substrate 200. When implemented by an AM (active matrix) method, the substrate 200 for the panel can further include thin film transistors assigned to each pixel.

[0102] Refer to Figure 7B , the light-emitting elements 100 transferred to adjacent pixels are arranged to be separated by a regular interval. Considering display characteristics, element arrangement, etc., the interval between adjacent light-emitting elements 100 among the light-emitting elements 100 transferred to the substrate 200 can be appropriately selected.

[0103] The substrate 200 can be set to have a relatively larger size than the light-emitting element transfer stamper 400.

[0104] More specifically, the active area 220 of the substrate 200 may be set to have an area larger than the area of the light-emitting element transfer stamp 400. In this case, in order to transfer the light-emitting elements 100 to all the pixels arranged in the active area 220, as Figure 7B shown, it is necessary to repeatedly perform a plurality of pick-up / transfer operations according to the area difference between the active area 220 and the light-emitting element transfer stamp 400.

[0105] In addition, the light-emitting element transfer processes such as the first transfer process T1 to the fourth transfer process T4 and the sixth transfer process T6 to the ninth transfer process T9 using the light-emitting element transfer stamp 400 may be performed not only on the active area 220 but also on the virtual area 230 of the substrate 200, that is, the non-driven display area.

[0106] Hereinafter, with reference to Figure 8A and Figure 8B a process of transferring a plurality of light-emitting elements to a substrate using a light-emitting element transfer stamp according to an embodiment of the present application will be described.

[0107] In this embodiment, the plurality of light-emitting elements 100 are described as including a plurality of first and second light-emitting elements 100a, 100a', 100b, and 100b'.

[0108] The plurality of first and second light-emitting elements 100a, 100a', 100b, and 100b' have the same shape and are only intended to distinguish between the light-emitting elements to be disposed in the non-overlapping transfer area 240 and the overlapping transfer area 250 of the substrate 200. That is, the plurality of first light-emitting elements 100a and 100a' refer to the light-emitting elements transferred to the non-overlapping transfer area (see Figure 11 240 in) of the substrate 200, and the plurality of second light-emitting elements 100b and 100b' refer to the light-emitting elements transferred to the overlapping transfer area (see Figure 11 250 in).

[0109] Figure 8A and Figure 8B are perspective views illustrating the first transfer process and the second transfer process using a light-emitting element transfer stamp according to an embodiment of the present application.

[0110] Referring to Figure 8A , a plurality of transfer areas such as the first transfer area TA1 to the ninth transfer area TA9 may be defined on the substrate 200. Although this embodiment describes an example in which the first transfer area TA1 to the ninth transfer area TA9 are defined on the substrate 200, an example in which a certain number of transfer areas selected from the first transfer area to the sixteenth transfer area are defined may also be described. However, the embodiment is not necessarily limited thereto.

[0111] Embodiments of the present application can be described by examples in which first transfer processes T1 to ninth transfer processes T9 are performed corresponding to first transfer regions TA1 to ninth transfer regions TA9.

[0112] In other words, corresponding to the first transfer region TA1 to the ninth transfer region TA9 divided on the substrate 200, the transfer processes T1 to T9 of the light-emitting elements using a single stamper 400 are performed one to nine times.

[0113] In this case, when the transfer process of the light-emitting elements is performed nine times, the transfer process can be performed such that during adjacent transfer processes, a part of each of the first transfer region TA1 to the ninth transfer region TA9 overlaps with each other.

[0114] In a state where the stamper 400 on which a plurality of light-emitting elements 100 are picked up is set corresponding to the first transfer region TA1 of the substrate 200, the first transfer process T1 is performed to transfer a plurality of first light-emitting elements 100a and second light-emitting elements 100b to the first transfer region TA1 of the substrate 200.

[0115] In this case, the first transfer region TA1 on the substrate 200 includes an active region 220 as a display driving region and a virtual region 230 as a display non-driving region.

[0116] Therefore, when the first transfer process T1 is performed, among the plurality of first light-emitting elements 100a and second light-emitting elements 100b picked up on the stamper 400, a plurality of first light-emitting elements 100a can be transferred to the first transfer region TA1 within the active region 220, and a plurality of second light-emitting elements 100b can be transferred to the virtual region 230 as a display non-driving region and partial regions of the second transfer region TA2 and the fourth transfer region TA4, that is, regions corresponding to the overlapping transfer regions.

[0117] Refer to Figure 8B , in the case where the stamper 400 is set corresponding to the second transfer region TA2 of the substrate 200, the second transfer process T2 is performed to transfer a plurality of first light-emitting elements 100a and second light-emitting elements 100b to the second transfer region TA2 of the substrate 200.

[0118] In this case, the second transfer region TA2 on the substrate 200 includes an active region 220 as a display driving region and a virtual region 230 as a display non-driving region.

[0119] Therefore, when the second transfer process T2 is performed, among the multiple first light-emitting elements 100a' and second light-emitting elements 100b' picked up on the stamper 400, the multiple first light-emitting elements 100a' can be transferred to the second transfer area TA2 within the active area 220, and the multiple second light-emitting elements 100b' can be transferred to the virtual area 230 as the non-driven display area, and partial areas of the first transfer area TA1, the third transfer area TA3, and the fifth transfer area TA5.

[0120] In other words, the second transfer process T2 is performed while overlapping with a part of the first transfer area TA1 where the light-emitting elements were transferred during the first transfer process T1. In other words, during the second transfer process T2, the multiple second light-emitting elements 100b' can be transferred to the overlapping area 250 of the first transfer area TA1 and the second transfer area TA2.

[0121] In this way, by continuously performing the first transfer process T1 to the ninth transfer process T9, the multiple first light-emitting elements 100a and 100a' and the second light-emitting elements 100b and 100b' are transferred to the first transfer area TA1 to the ninth transfer area TA9 of the substrate 200.

[0122] During the first transfer process T1 to the ninth transfer process T9, overlapping transfer areas ( Figure 11 such as 250 therein) are formed between adjacent transfer areas, and the multiple second light-emitting elements 100b and 100b' are transferred and disposed in these overlapping transfer areas 250.

[0123] In addition, while performing the first transfer process T1 to the fourth transfer process T4 and the sixth transfer process T6 to the ninth transfer process T9 except for the fifth transfer process T5, the multiple second light-emitting elements 100b and 100b' can also be transferred and disposed in the virtual area 230 of the substrate 200. The multiple second light-emitting elements 100b and 100b' transferred to the virtual area 230 are not used for display driving.

[0124] In addition, during the first transfer process T1 to the ninth transfer process T9 using the stamper 400, the multiple second light-emitting elements 100b and 100b' are transferred and disposed in the overlapping transfer area 250, that is, they are transmitted and disposed without overlapping each other.

[0125] The stamper 400 can have an area that is a certain size larger than each of the transfer areas TA1 to TA9 of the substrate 200, such as the overlapping transfer area 250.

[0126] In this manner, since the first transfer process T1 to the ninth transfer process T9 using the stamper 400 are performed such that a plurality of second light-emitting elements 100b and 100b' are transferred and disposed in the overlapping transfer region 250, the process capability differences between the transfer processes using the stamper 400 can be offset.

[0127] Accordingly, by the transfer processes using the stamper 400, a plurality of second light-emitting elements 100b and 100b' can be transferred to the overlapping transfer region 250 of the substrate 200 in an overlapping manner, thereby reducing the smear visibility caused by the process capability differences of the respective stampers.

[0128] Hereinafter, reference will be made to Figure 9 and Figure 10 to describe a stamper structure for transferring light-emitting elements according to an embodiment of the present disclosure.

[0129] Figure 9 is a plan view illustrating a light-emitting element transfer stamper according to an embodiment of the present application. Figure 10 is a cross-sectional view taken along line III-III' in Figure 9 above.

[0130] Referring to Figure 9 , a light-emitting element transfer stamper 400 according to an embodiment of the present application includes: a non-overlapping stamper pattern region 420 defined in a central portion of the upper surface of the stamper substrate 410, and an overlapping stamper pattern region 430 adjacent to the outer periphery of the non-overlapping stamper pattern region 420.

[0131] A plurality of first pick-up transfer patterns 440a may be disposed at regular intervals in the non-overlapping stamper pattern region 420 along a first direction as a horizontal direction X and a second direction as a vertical direction Y, and a plurality of second pick-up transfer patterns 440b may be disposed in the overlapping stamper pattern region 430.

[0132] In a state where a plurality of light-emitting elements have been picked up from the growth substrate, the plurality of first pick-up transfer patterns 440a for picking up and transferring the plurality of light-emitting elements may be disposed corresponding to the non-overlapping transfer region ( Figure 11 240 in Figure 11 ) of the substrate (

[0133] 200 in

[0134] The overlapping stamp pattern regions 430 may include: a first overlapping stamp pattern region 430a and a second overlapping stamp pattern region 430b that are disposed relative to each other in a first direction as the horizontal direction X with a non-overlapping stamp pattern region 420 therebetween; and a third overlapping stamp pattern region 430c and a fourth overlapping stamp pattern region 430d that are disposed relative to each other in a second direction as the vertical direction Y with a non-overlapping stamp pattern region 420 therebetween.

[0135] A plurality of second pick-up transfer patterns 440b provided in the first overlapping stamp pattern region 430a may be asymmetric with a plurality of second pick-up transfer patterns 440b provided in the second overlapping stamp pattern region 430b on the opposite side with a non-overlapping stamp pattern region 420 therebetween, and may have a different number or the same number as that thereof.

[0136] A plurality of second pick-up transfer patterns 440b provided in the third overlapping stamp pattern region 430c may be asymmetric with a plurality of second pick-up transfer patterns 440b provided in the fourth overlapping stamp pattern region 430d on the opposite side with a non-overlapping stamp pattern region 420 therebetween, and may have a different number or the same number as that thereof.

[0137] In other words, even when performing the first transfer process to the ninth transfer process by using the stamp 400, during the transfer process, a plurality of second light-emitting elements ( Figure 13 100b and 100b' in) picked up on a plurality of second pick-up transfer patterns 440b provided in the first overlapping stamp pattern region 430a to the fourth overlapping stamp pattern region 430d may be transferred and disposed at desired transfer positions without overlapping with each other within the overlapping transfer region 250 of the substrate.

[0138] Referring to Figure 10 , the light-emitting element transfer stamp 400 according to the present application includes a stamp substrate 410 and a plurality of pick-up transfer patterns 440 formed at regular intervals on the upper surface of the stamp substrate 410.

[0139] The plurality of pick-up transfer patterns 440 include a plurality of first pick-up transfer patterns 440a provided on the non-overlapping stamp pattern region 420 of the stamp substrate 410 and a plurality of second pick-up transfer patterns 440b provided in the overlapping stamp pattern region 430.

[0140] The number of the plurality of second pick-up transfer patterns 440b provided in the overlapping stamp pattern region 430 may be in the range of 1% to 10% of the total number of the plurality of first pick-up transfer patterns 440a and the plurality of second pick-up transfer patterns 440b provided on the stamp substrate 410.

[0141] The impression substrate 410 can be used as a transfer device for transferring the light-emitting element 100 from the growth substrate ( Figure 7A in 300) to the substrate ( Figure 7B in 200).

[0142] A quartz substrate, a sapphire substrate, or a silicon substrate can be used as the impression substrate 210. However, the embodiments are not limited thereto.

[0143] A plurality of first pick-up transfer patterns 440a and second pick-up transfer patterns 440b are used to pick up the light-emitting element using a material having surface adhesion characteristics, and the applied flexible viscoelastic material allows picking up light-emitting elements having various shapes, structures, and sizes without a conventional complex spring structure.

[0144] The plurality of first pick-up transfer patterns 440a and second pick-up transfer patterns 440b may have a rectangular, circular, or polygonal structure, but are not limited thereto.

[0145] The material of the plurality of first pick-up transfer patterns 440a and second pick-up transfer patterns 440b can be PDMS, PAC, urethane, acrylic, or epoxy resin. However, the embodiments are not limited thereto. The plurality of first pick-up transfer patterns 440a and second pick-up transfer patterns 440b can have any thickness.

[0146] The plurality of first pick-up transfer patterns 440a and second pick-up transfer patterns 440b can undergo thermal expansion and deformation due to the heat applied from the back surface of the impression substrate 410, resulting in the deformation of their surface shape into a convex shape protruding in the vertical direction of the impression substrate 210, i.e., a rounded shape, which is beneficial for picking up the light-emitting element.

[0147] The mechanism head for bonding the light-emitting element transfer impression 400 is not limited to a vacuum head, an electrostatic head, etc.

[0148] The light-emitting element transfer impression 400 according to the present application has a predetermined adhesion (or adsorption) characteristic such that it can selectively pick up the light-emitting element 100 provided at a predetermined position from the growth substrate ( Figure 7A in 300), and when the adhesion force is released, it can transfer the light-emitting element 100 to the corresponding pixel on the substrate ( Figure 7B in 200).

[0149] The release of the adhesion force of the pick-up transfer pattern 440 can be achieved using thermal or chemical characteristics. For example, a release layer can be provided between the impression substrate 410 and the light-emitting element 100, and the adhesion force can be released by irradiating the release layer with a laser.

[0150] The process of transferring a plurality of light-emitting elements according to an embodiment of the present application is described below.

[0151] Although the embodiments of the present application describe the first transfer process T1 and the second transfer process T2 by way of example, the first transfer process and the second transfer process can be equally applied to the third transfer process T3 to the ninth transfer process T9.

[0152] Figure 11 is a plan view of a substrate having a transfer region defined thereon according to an embodiment of the present application. Figure 12 is Figure 11 an enlarged view of region C in

[0153] Referring to Figure 11 , the substrate 200 for a panel on which light-emitting elements are transferred by the light-emitting element transfer stamp 400 according to an embodiment of the present application may include an effective region 220 as a display driving region and a virtual region 230 as a display non-driving region on the outer periphery of the effective region 220.

[0154] The effective region 220 may include first to ninth non-overlapping transfer regions 240 and an overlapping transfer region 250 provided outside the first to ninth non-overlapping transfer regions 240.

[0155] In the virtual region 230, during the first transfer process to the fourth transfer process and the sixth transfer process to the ninth transfer process except for the fifth transfer process, a plurality of second light-emitting elements 100b picked up by a plurality of second light-emitting element transfer patterns 440b in the first overlapping pick-up transfer regions 430a to the fourth overlapping pick-up transfer regions 430d provided in the stamp 400 may be transferred and disposed.

[0156] Referring to Figure 11 and Figure 12 , a non-overlapping transfer region 240 may be formed in the central region of the fifth transfer region TA5 on the substrate 200 by the fifth transfer process T5, and an overlapping transfer region 250 may be formed near the outer periphery of the non-overlapping transfer region 240.

[0157] That is, the overlapping transfer region 250 defined during the fifth transfer process T5 and the respective overlapping transfer regions 250 when performing the second transfer process T2, the fourth transfer process T4, the sixth transfer process T6, and the eighth transfer process T8 may have an overlapping surface with each other.

[0158] In addition, the overlapping transfer region 250 defined during the fifth transfer process T5 and the respective overlapping transfer regions 250 when performing the first transfer process T1, the third transfer process T3, the seventh transfer process T7, and the ninth transfer process T9 may have an overlapping corner with each other.

[0159] In other words, an overlapping transfer region 250 can be formed between adjacent transfer processes among the first transfer process T1 to the ninth transfer process T9. By using the stamper 400 to form the overlapping transfer region 250 on a plurality of transfer regions TA1 to TA9 defined on the substrate 200 during the first transfer process to the ninth transfer process, the process capability differences between the transfer processes in the overlapping transfer region 250 can be offset by the stamper 400 in the overlapping transfer region 250, thereby improving the visibility of the stamper ghosting.

[0160] In order to improve the visibility of the stamper ghosting by offsetting the process capability differences between the transfer processes in the overlapping transfer region 250, it is desirable to increase the area of the overlapping transfer region 250.

[0161] However, when the area of the overlapping transfer region 250 increases, the area of the virtual region 230 also increases, resulting in an increase in the number of light-emitting elements 200 provided in the virtual region 230.

[0162] Although this can improve the visibility of the stamper ghosting in the overlapping transfer region 250, it will reduce the number of light-emitting elements 100 provided in the substrate 200, which will result in a lower profit margin.

[0163] Therefore, in order to limit the number of light-emitting elements 100 provided in the virtual region 230 while appropriately maintaining the area of the overlapping transfer region 250, the number of light-emitting elements 100 transferred and provided in the overlapping transfer region 250 formed on the substrate 200 can be set within the range of 1 to 10% of the number of light-emitting elements 100 transferred and provided in the entire substrate 200.

[0164] Alternatively, the number of light-emitting elements 100 transferred and provided in the overlapping transfer region 250 of the substrate 200 can be equal to or less than the number of light-emitting elements 100 transferred to the virtual region 230 of the substrate 200.

[0165] In particular, as the area of the virtual region 230 increases, the overlapping transfer region 250 also increases, so it is necessary to effectively adjust the area of the virtual region 230, so as to improve the visibility of the stamper ghosting by using the overlapping transfer region 250 while keeping the area of the virtual region 230 as small as possible.

[0166] Therefore, by performing the first transfer process T1 using the stamper 400, a plurality of second light-emitting elements 100b can be transferred and provided in the overlapping transfer region 250, and then, by performing the second transfer process T2 using the stamper 400 used in the first transfer process T1, a plurality of second light-emitting elements 100b' can be transferred and provided in the overlapping transfer region 250.

[0167] This can cancel out the difference in the degree of luminous efficiency in the overlapping transfer region 250, resulting in reduced ghost visibility.

[0168] Figure 13 is a cross-sectional view taken along Figure 11 the line IV-IV in.

[0169] Referring to Figure 13 , by performing a first transfer process T1 and a second transfer process T2 using a stamp for transferring light-emitting elements according to an embodiment of the present application, a plurality of first light-emitting elements 100a and 100a' and a plurality of second light-emitting elements 100b and 100b' are transferred and disposed on the substrate 200.

[0170] Among the plurality of first light-emitting elements 100a and second light-emitting elements 100b, the first light-emitting element 100a is a light-emitting element that is transferred during the first transfer process T1 and disposed in the non-overlapping transfer region 240 defined in the first transfer region TA1, and the plurality of second light-emitting elements 100b are light-emitting elements that are transferred during the first transfer process T1 and disposed in the overlapping transfer region 250 of the first transfer region TA1.

[0171] In addition, among the plurality of first light-emitting elements 100a' and second light-emitting elements 100b', the first light-emitting element 100a' is a light-emitting element that is transferred during the second transfer process T2 and disposed in the non-overlapping transfer region 240 defined in the second transfer region TA2, and the plurality of second light-emitting elements 100b' are light-emitting elements that are transferred during the second transfer process and disposed in the overlapping transfer region 250 of the second transfer region TA2.

[0172] In this embodiment, the plurality of first light-emitting elements 100a and second light-emitting elements 100b that are transferred and disposed in the first transfer process T1, and the plurality of first light-emitting elements 100a' and second light-emitting elements 100b' that are transferred and disposed in the second transfer process T2 are light-emitting elements of the same type. This definition is only used to distinguish the light-emitting elements that are transferred and disposed during the first transfer process T1 and the second transfer process T2.

[0173] In addition, in this embodiment, all the light-emitting elements that are transferred and disposed during the first transfer process T to the ninth transfer process T9 have the same area and size, and the same single stamp 400 is used to pick up the light-emitting elements disposed on the growth substrate 300 and transfer them to the substrate 200.

[0174] Referring to Figure 13, through the first transfer process T1 using the stamper 400, a plurality of first light-emitting elements 100a and second light-emitting elements 100b are transferred and disposed on the first transfer region TA1 of the substrate 200.

[0175] A plurality of first light-emitting elements 100a are transferred and disposed within the non-overlapping transfer regions 240 of the substrate 200.

[0176] A plurality of first light-emitting elements 100a are arranged at regular intervals in the non-overlapping transfer regions 240 along a first direction as the horizontal direction and a second direction as the vertical direction.

[0177] A plurality of second light-emitting elements 100b are transferred and disposed within the overlapping transfer regions 250 of the substrate 200.

[0178] A plurality of second light-emitting elements 100b are arranged at regular intervals within the overlapping transfer regions 250 of the substrate 2000 and are alternately arranged along a first direction as the horizontal direction and a second direction as the vertical direction.

[0179] Continue to refer to Figure 13 , a plurality of first light-emitting elements 100a' and second light-emitting elements 100b' are transferred and disposed on the second transfer region TA2 of the substrate 200 by using the first transfer process T2 of the stamper 400.

[0180] A plurality of first light-emitting elements 100a' are transferred and disposed within the non-overlapping transfer regions 240 of the second transfer region TA2 of the substrate 200.

[0181] A plurality of first light-emitting elements 100a' are arranged at regular intervals in the non-overlapping transfer regions 240 along a first direction as the horizontal direction and a second direction as the vertical direction.

[0182] A plurality of second light-emitting elements 100b' are transferred and disposed within the overlapping transfer regions 250 of the second transfer region TA2 of the substrate 200.

[0183] Herein, the overlapping transfer region 250 refers to a shared region that is transferred by overlapping each other when the first transfer process T1 and the second transfer process T2 are performed.

[0184] A plurality of second light-emitting elements 100b' are arranged at regular intervals within the overlapping transfer regions 250 of the substrate 200 and are alternately arranged along a first direction as the horizontal direction and a second direction as the vertical direction.

[0185] In this case, a plurality of second light-emitting elements 100b transferred during the first transfer process T1 and a plurality of second light-emitting elements 100b' transferred during the second transfer process T2 are arranged at regular intervals within an overlapping transfer region 250 of a substrate 200.

[0186] In addition, the plurality of second light-emitting elements 100b and 100b' transferred to the overlapping transfer region 250 during the first transfer process T1 and the second transfer process T2 are arranged at predetermined positions that do not overlap with each other.

[0187] In addition, the plurality of second light-emitting elements 100b and 100b' may be arranged at regular intervals in the overlapping transfer region 250 along a first direction as a horizontal direction and a second direction as a vertical direction.

[0188] In addition, in addition to during the first transfer process T1 and the second transfer process T2, during the third transfer process T3 to the ninth transfer process T9, the plurality of second light-emitting elements 100b and 100b' may be arranged at regular intervals in the overlapping transfer regions 250 that overlap with each other along a first direction as a horizontal direction and a second direction as a vertical direction.

[0189] As described above, during the first transfer process to the ninth transfer process, the plurality of second light-emitting devices 100b and 100b' may be arranged in the overlapping transfer region 250 defined in each transfer region without overlapping with each other.

[0190] Figure 14 is a cross-sectional view taken along line V-V' in Figure 13 in. Figure 15 is a cross-sectional view taken along line VI-VI' in Figure 13 in.

[0191] Refer to Figure 14 and Figure 15 , in a display device according to an embodiment of the present application, a bank pattern 112 is provided on a substrate 200, and a plurality of first electrodes 102 are provided on the bank pattern 112.

[0192] A plurality of light-emitting elements 100 are provided on the plurality of first electrodes 102, and a first optical layer 136 is provided between the plurality of light-emitting elements 100.

[0193] The plurality of light-emitting elements 100 may include a plurality of first light-emitting elements 100a and 100a' and a plurality of second light-emitting elements 100b and 100b'. The plurality of first light-emitting elements 100a and 100a' and the plurality of second light-emitting elements 100b and 100b' may have the same structure, area, and size.

[0194] In the embodiments of the present application, the multiple first light-emitting elements 100a and 100a' and the multiple second light-emitting elements 100b and 100b' are defined to distinguish the light-emitting elements transferred through the first transfer process T1 to the ninth transfer process T9 and disposed on the non-overlapping transfer region 240 and the overlapping transfer region 250.

[0195] A second electrode 104 is disposed on the multiple light-emitting elements 100 and the first optical layer 136.

[0196] Then, a black matrix 128 is disposed on the second electrode 104 to overlap with the region between the multiple light-emitting elements 100.

[0197] The light emitted from the multiple light-emitting elements 100 is emitted from the region between the black matrices 128.

[0198] Refer to Figure 14 and Figure 15 During the first transfer process T1, the multiple first light-emitting elements 100a and the second light-emitting elements 100b are transferred and disposed in the non-overlapping transfer region 240 and the overlapping transfer region 250 respectively defined in the first transfer region TA1 of the substrate 200.

[0199] Refer to Figure 14 and Figure 15 The multiple first light-emitting elements 100a and 100a' transferred and disposed in the non-overlapping transfer region 240 along the first direction as the horizontal direction are set to be symmetric with respect to the multiple first light-emitting elements 100a and 100a' disposed vertically one above the other along the second direction as the vertical direction.

[0200] Refer to Figure 14 and Figure 15 During the first transfer process T1, the multiple second light-emitting elements 100b transferred and disposed in the overlapping transfer region 250 are alternately disposed along the first direction as the horizontal direction and the second direction as the vertical direction.

[0201] In addition, the multiple second light-emitting elements 100b' transferred and disposed in the overlapping transfer region 250 during the second transfer process T2 are alternately disposed along the first direction as the horizontal direction and the second direction as the vertical direction.

[0202] In other words, within the overlapping transfer region 250, the multiple second light-emitting elements 100b and 100b' are alternately disposed at regular intervals without overlapping each other.

[0203] For example, when performing the first transfer process T1, within the overlapping transfer region 250, in the first row along the first direction, three second light-emitting elements 100b are transferred and arranged at regular intervals, and in the second row, which is the next row of the first row, two second light-emitting elements 100b that are asymmetric to the three second light-emitting elements 100b in the first row are transferred and arranged, so that they do not overlap with each other.

[0204] Therefore, for each row, the multiple second light-emitting elements 100b arranged within the overlapping transfer region 250 are arranged alternately.

[0205] On the other hand, in the second transfer process T2, within the overlapping transfer region 250, in the first row along the first direction, two second light-emitting elements 100b' are transferred and arranged at regular intervals, and in the second row, which is the next row of the first row, three second light-emitting elements 100b' that are asymmetric to the two second light-emitting elements 100b' in the first row are transferred and arranged, so that they do not overlap with each other.

[0206] Therefore, the multiple second light-emitting elements 100b' arranged within the overlapping transfer region 250 are arranged alternately in each of the upper and lower rows.

[0207] In addition, during the second transfer process T2, the multiple second light-emitting elements 100b' arranged within the overlapping transfer region 250 are arranged between the multiple second light-emitting elements 100b that are transferred and arranged during the first transfer process T1.

[0208] Therefore, the multiple second light-emitting elements 100b' to be arranged within the overlapping transfer region 250 during the second transfer process T2 are arranged for each row and column to correspond to the multiple second light-emitting elements 100b arranged within the overlapping transfer region 250 during the first transfer process T1.

[0209] Continuing to refer to Figure 14 and Figure 15 , the multiple first light-emitting elements 100a and 100a' and the multiple second light-emitting elements 100b and 100b' are arranged on the solder pattern 118 on the first electrode 102 in the non-overlapping transfer region 240 and the overlapping transfer region 250 of the substrate 200 to be electrically connected to the first electrode 102.

[0210] In addition, during the first transfer process T1 and the second transfer process T2, the multiple first light-emitting elements 100a and the second light-emitting elements 100b' are respectively transferred and arranged in the non-overlapping transfer region 240 and the overlapping transfer region 250 defined in the second transfer region TA1 of the substrate 200.

[0211] A plurality of first light-emitting elements 100a' and second light-emitting elements 100b' are disposed on a solder pattern 118, and the solder pattern 118 is disposed on and electrically connected to a plurality of first electrodes 102 in non-overlapping transfer regions 240 and overlapping transfer regions 250 of a substrate 200.

[0212] During a second transfer process T2, different from the first transfer process T1, the plurality of first light-emitting elements 100a' and second light-emitting elements 100b' can be transferred and disposed in a state where they are slightly offset by a separation distance d, rather than being precisely disposed on the solder pattern 118 on the first electrodes 102.

[0213] This means that in each process of transferring a stamper for picking up and transferring light-emitting elements to transfer the light-emitting elements 100 onto the substrate 200, due to differences in the transfer process capabilities of the stamper, performing multiple transfer processes using the stamper may not precisely transfer the light-emitting elements. However, due to slight offsets during the operation of the picking and transferring device, the light-emitting elements can be transferred in a state where a part of each light-emitting element disposed on the solder pattern 118 on the first electrodes 102 is slightly offset by the separation distance d.

[0214] As a result, within the overlapping transfer region 250, some of the plurality of second light-emitting elements 100b' may be disposed to partially overlap a black matrix 128, and the black matrix 128 is disposed to overlap between the light-emitting elements.

[0215] Therefore, compared with the first transfer process, a part of the light emitted from the plurality of second light-emitting elements 100b' within the overlapping transfer region 250 can be blocked by the black matrix 128, resulting in a reduction in luminous efficiency.

[0216] However, the plurality of second light-emitting elements 100b transferred and disposed in the overlapping transfer region 250 during the first transfer process T1 are disposed without offset on the solder pattern 118 on the first electrodes 102, and thus do not overlap with the black matrix 128 disposed to overlap between the plurality of second light-emitting elements 100.

[0217] Therefore, the luminous efficiency of the plurality of second light-emitting elements 100b transferred and disposed in the overlapping transfer region 250 during the first transfer process T1 is not reduced, and the same luminous efficiency as that of the plurality of first light-emitting elements 100a disposed in the non-overlapping transfer region 240 can be maintained.

[0218] As a result, due to the transfer performance difference during the first transfer process T1 and the second transfer process T2, a plurality of second light-emitting elements 100b having excellent luminous efficiency and a plurality of second light-emitting elements 100b' having reduced luminous efficiency can be transferred and cross-set in the overlapping transfer region 250. Therefore, the difference in the degree of luminous efficiency in the overlapping transfer region 250 can be offset, and thus the effect of reducing the ghost visibility at the boundary between the transfer regions can be achieved.

[0219] Figure 16A and Figure 16B are diagrams showing whether the stamp ghosting is visible when using a stamp to transfer a plurality of light-emitting elements during the process according to an embodiment of the present application, with and without an overlapping transfer region.

[0220] Referring to Figure 16A , by performing a plurality of transfer processes on a substrate using a stamp, a plurality of light-emitting elements are transferred and set in the substrate. In this case, by performing a plurality of transfer processes without an overlapping transfer region during the transfer process, a plurality of light-emitting elements are transferred and set in the substrate.

[0221] At this time, as shown in region E of Figure 16A , it can be confirmed that during adjacent transfer processes, such as during the first transfer process T1 and the second transfer process T2, the stamp ghosting is clearly visible at the boundary between the first transfer region and the second transfer region.

[0222] However, referring to Figure 16B showing an embodiment of the present application, it shows the case where a plurality of light-emitting elements are transferred and set in the substrate by performing a plurality of transfer processes using a stamp. This case represents that during the plurality of transfer processes, a plurality of light-emitting elements are transferred and set in the overlapping transfer region.

[0223] In this case, as shown in region F of Figure 16B , it can be confirmed that by forming an overlapping transfer region (250 in Figure 13 T1) and the second transfer process ( Figure 13 T2 in Figure 13 ) between the first transfer region and the second transfer region during adjacent transfer processes, the visibility at the boundary between the first transfer region and the second transfer region due to the stamp ghosting is improved.

[0224] The display device according to an embodiment of the present application can be applied to mobile devices, video phones, smart watches, watch phones, wearable devices, foldable devices, rollable devices, bendable devices, flexible devices, curved devices, sliding devices, variable devices, electronic notebooks, e-books, portable multimedia players (PMPs), personal digital assistants (PDAs), MP3 players, mobile medical devices, desktop PCs, laptop PCs, netbook computers, workstations, navigation systems, vehicle display devices, theater display devices, televisions, wallpaper devices, signage devices, gaming devices, laptop computers, monitors, cameras, camcorders, household appliances, etc. In addition, the display device according to one or more embodiments of the present application can be applied to an organic light-emitting lighting device or an inorganic light-emitting lighting device.

[0225] The stamper for transferring a light-emitting element according to various embodiments of the present disclosure can be described as follows.

[0226] The stamper for transferring a light-emitting element according to an embodiment of the present disclosure may include: a stamper substrate; a non-overlapping stamper pattern region defined on the stamper substrate, and an overlapping stamper pattern region adjacent to the outer periphery of the non-overlapping stamper pattern region; a plurality of first pick-up transfer patterns disposed in the non-overlapping stamper pattern region; and a plurality of second pick-up transfer patterns disposed in different rows in the overlapping stamper pattern region with the non-overlapping stamper pattern region therebetween.

[0227] According to an embodiment of the present disclosure, the overlapping stamper pattern region may include a first overlapping stamper pattern region and a second overlapping stamper pattern region, and a third overlapping stamper pattern region and a fourth overlapping stamper pattern region, which are disposed to face each other with the non-overlapping stamper pattern region therebetween.

[0228] According to an embodiment of the present disclosure, the plurality of second pick-up transfer patterns disposed in the first overlapping stamper pattern region and the second overlapping stamper pattern region facing each other may be located in different rows, and the plurality of second pick-up transfer patterns disposed in the third overlapping stamper pattern region and the fourth overlapping stamper pattern region facing each other may be located in different rows.

[0229] According to an embodiment of the present disclosure, the number of the plurality of second pick-up transfer patterns that can be disposed in the overlapping stamper pattern region may be different or the same.

[0230] According to an embodiment of the present disclosure, the number of the plurality of second pick-up transfer patterns provided in the overlapping imprint pattern region may be in the range of 1% to 10% of the total number of the plurality of first pick-up transfer patterns and the plurality of second pick-up transfer patterns provided in all of the overlapping imprint pattern region and the non-overlapping imprint pattern region.

[0231] A method of using an imprint transfer light-emitting element according to an embodiment of the present disclosure may include: preparing a substrate having a plurality of transfer regions divided into a non-overlapping transfer region and an overlapping transfer region; preparing an imprint including a plurality of first pick-up transfer patterns configured to transfer a plurality of first light-emitting elements to the non-overlapping transfer region of the substrate, and a plurality of second pick-up transfer patterns configured to transfer a plurality of second light-emitting elements to the overlapping transfer region of the substrate; and performing a plurality of transfer processes by using the imprint to transfer the plurality of first light-emitting elements picked up on the plurality of first pick-up transfer patterns to the non-overlapping transfer region of the substrate, and transfer the plurality of second light-emitting elements picked up on the plurality of second pick-up transfer patterns to the overlapping transfer region.

[0232] According to an embodiment of the present disclosure, the plurality of second light-emitting elements are transferred to the overlapping transfer region of each of the plurality of transfer regions by performing the transfer process at least twice.

[0233] According to an embodiment of the present disclosure, among the plurality of second light-emitting elements transferred to the overlapping transfer region of each of the plurality of transfer regions, the plurality of second light-emitting elements transferred during a first transfer process and the plurality of second light-emitting elements transferred during a second transfer process may be transferred to the overlapping transfer region without overlapping each other.

[0234] According to an embodiment of the present disclosure, the plurality of first light-emitting elements may be transferred to the non-overlapping transfer region of each of the plurality of transfer regions by a single transfer process.

[0235] According to an embodiment of the present disclosure, the overlapping transfer region of the substrate may include: a first overlapping transfer region and a second overlapping transfer region facing each other in a first direction as a horizontal direction with the non-overlapping transfer region therebetween; and a third overlapping transfer region and a fourth overlapping transfer region facing each other in a second direction as a vertical direction with the non-overlapping transfer region therebetween.

[0236] According to an embodiment of the present disclosure, the plurality of second light-emitting elements disposed in the first overlapping transfer region and the second overlapping transfer region may be located in different rows in the first direction and the second direction, and the plurality of second light-emitting elements disposed in the third overlapping transfer region and the fourth overlapping transfer region may be located in different rows in the first direction and the second direction.

[0237] According to an embodiment of the present disclosure, the number of the plurality of second light-emitting elements disposed in the first overlapping transfer region and the second overlapping transfer region may be different or the same, and the number of the plurality of second light-emitting elements disposed in the third overlapping transfer region and the fourth overlapping transfer region may be different or the same.

[0238] According to an embodiment of the present disclosure, the number of the plurality of second light-emitting elements disposed in the overlapping transfer region may be in the range of 1% to 10% of the total number of the plurality of first light-emitting elements and the plurality of second light-emitting elements transferred to the non-overlapping transfer region and the overlapping transfer region.

[0239] According to an embodiment of the present disclosure, when performing a plurality of transfer processes, adjacent transfer regions among the plurality of transfer regions of the substrate may share the overlapping transfer region.

[0240] According to an embodiment of the present disclosure, the number of the plurality of second light-emitting elements transferred to the overlapping transfer region may be less than or equal to the number of the plurality of second light-emitting elements transferred to the virtual region of the substrate.

[0241] A display device according to an embodiment of the present disclosure may include: a substrate having a plurality of transfer regions; a non-overlapping transfer region and an overlapping transfer region defined in each of the plurality of transfer regions; a plurality of bank patterns disposed in the non-overlapping transfer region and the overlapping transfer region of the substrate; a plurality of first electrodes disposed on the plurality of bank patterns; a plurality of light-emitting elements disposed on the plurality of first electrodes; and a second electrode disposed on the plurality of light-emitting elements, wherein the light-emitting elements disposed in the overlapping transfer region include light-emitting elements overlapping the bank patterns on the first electrodes and light-emitting elements having a portion not overlapping the bank patterns on the first electrodes.

[0242] According to an embodiment of the present disclosure, the number of the plurality of light-emitting elements disposed in the overlapping transfer region is in the range of 1% to 10% of the total number of the plurality of light-emitting elements transferred in the non-overlapping transfer region and the overlapping transfer region.

[0243] According to an embodiment of the present disclosure, each of the overlapping transfer regions of the transfer region includes a light-emitting element overlapping the bank pattern on the first electrode and a light-emitting element having a portion that does not overlap the bank pattern on the first electrode.

[0244] According to an embodiment of the present disclosure, the number of the plurality of light-emitting elements disposed in the overlapping transfer region is less than or equal to the number of the plurality of light-emitting elements transferred to the virtual region of the substrate.

[0245] According to an embodiment of the present disclosure, the display device further includes a black matrix disposed on the second electrode to overlap a region between the plurality of light-emitting elements, and the light-emitting element having a portion that does not overlap the bank pattern is disposed to partially overlap the black matrix.

[0246] The effects of the present application are not limited to the above effects, and those skilled in the art will be able to clearly understand other effects not mentioned based on the above specific embodiments.

[0247] Although the embodiments of the present disclosure have been described in more detail with reference to the accompanying drawings, the present disclosure is not necessarily limited to these embodiments, and various modifications can be made without departing from the technical concept of the present disclosure. Therefore, the embodiments disclosed in the present disclosure are not intended to limit the technical spirit of the present disclosure, but to describe it, and the scope of the technical spirit of the present disclosure is not limited to these embodiments. Therefore, it should be understood that the above embodiments are illustrative rather than restrictive in all respects.

Claims

1. A stamp for transferring a light-emitting element, comprising: Impression base; defining a non-overlapping stamp pattern region on the stamp substrate and an overlapping stamp pattern region adjacent to the periphery of the non-overlapping stamp pattern region; a plurality of first pick-up transfer patterns, the plurality of first pick-up transfer patterns being disposed in the non-overlapping stamp pattern region; as well as A plurality of second pickup transfer patterns are disposed in different rows in the overlapping stamp pattern area with the non-overlapping stamp pattern area interposed therebetween.

2. The stamp according to claim 1, wherein the overlapping stamp pattern area includes a first overlapping stamp pattern area and a second overlapping stamp pattern area, and a third overlapping stamp pattern area and a fourth overlapping stamp pattern area, which are arranged to face each other with the non-overlapping stamp pattern area interposed therebetween.

3. The stamp according to claim 2, wherein the plurality of second pick-up transfer patterns arranged in the first overlapping stamp pattern area and the second overlapping stamp pattern area facing each other are located in different rows, and the plurality of second pick-up transfer patterns arranged in the third overlapping stamp pattern area and the fourth overlapping stamp pattern area facing each other are located in different rows. 4 . The stamp according to claim 1 , wherein the plurality of second pick-up transfer patterns disposed in the overlapping stamp pattern area are different in number or the same in number.

5. The stamp according to claim 1, wherein the number of the plurality of second pick-up transfer patterns provided in the overlapping stamp pattern area is in the range of 1% to 10% of the total number of the plurality of first pick-up transfer patterns and the second pick-up transfer patterns provided in all of the overlapping stamp pattern area and the non-overlapping stamp pattern area.

6. A method for transferring a light-emitting element using a stamp, the method comprising: preparing a substrate having a plurality of transfer regions divided into non-overlapping transfer regions and overlapping transfer regions; preparing a stamp, the stamp comprising a plurality of first pick-up transfer patterns configured to transfer a plurality of first light-emitting elements to the non-overlapping transfer regions of the substrate, and a plurality of second pick-up transfer patterns configured to transfer a plurality of second light-emitting elements to the overlapping transfer regions of the substrate; as well as By performing a plurality of transfer processes using the stamp, the plurality of first light emitting elements picked up on the plurality of first pick-up transfer patterns are transferred to the non-overlapping transfer region of the substrate, and the plurality of second light emitting elements picked up on the plurality of second pick-up transfer patterns are transferred to the overlapping transfer region. 7 . The method according to claim 6 , wherein the plurality of second light emitting elements are transferred to the overlapping transfer region of each of the plurality of transfer regions by performing the transfer process at least twice.

8. The method according to claim 7, wherein: Among the plurality of second light emitting elements transferred to the overlapping transfer region of each of the plurality of transfer regions, the plurality of second light emitting elements transferred during the first transfer process and the plurality of second light emitting elements transferred during the second transfer process are transferred to the overlapping transfer region without overlapping each other. 9 . The method of claim 6 , wherein the plurality of first light emitting elements are transferred to the non-overlapping transfer regions of each of the plurality of transfer regions by a single transfer process.

10. The method of claim 8, wherein the overlapping transfer region of the substrate comprises: a first overlapping transfer region and a second overlapping transfer region disposed facing each other in a first direction being a horizontal direction with the non-overlapping transfer region interposed therebetween; and a third overlapping transfer region and a fourth overlapping transfer region disposed facing each other in a second direction as a vertical direction with the non-overlapping transfer region interposed therebetween.

11. The method according to claim 10, wherein the plurality of second light-emitting elements arranged in the first overlapping transfer region and the second overlapping transfer region are located in different rows in the first direction and the second direction, and the plurality of second light-emitting elements arranged in the third overlapping transfer region and the fourth overlapping transfer region are located in different rows in the first direction and the second direction.

12. The method according to claim 11, wherein the number of the plurality of second light-emitting elements arranged in the first overlapping transfer region and the second overlapping transfer region is different or the same, and the number of the plurality of second light-emitting elements arranged in the third overlapping transfer region and the fourth overlapping transfer region is different or the same.

13. The method of claim 6, wherein the number of the plurality of second light-emitting elements disposed in the overlapping transfer region is within a range of 1% to 10% of the total number of the plurality of first light-emitting elements and the second light-emitting elements transferred in the non-overlapping transfer region and the overlapping transfer region. 14 . The method of claim 6 , wherein when a plurality of transfer processes are performed, mutually adjacent transfer regions among a plurality of transfer regions of the substrate share the overlapped transfer region. 15 . The method of claim 6 , wherein a number of the plurality of second light emitting elements transferred to the overlapping transfer region is less than or equal to a number of the plurality of second light emitting elements transferred to the dummy region of the substrate.

16. A display device, comprising: a substrate having a plurality of transfer regions; defining non-overlapping transfer regions and overlapping transfer regions in each of the plurality of transfer regions; a plurality of bank patterns disposed in the non-overlap transfer region and the overlap transfer region of the substrate; a plurality of first electrodes, the plurality of first electrodes being disposed on the plurality of bank patterns; A plurality of light emitting elements, wherein the plurality of light emitting elements are disposed on the plurality of first electrodes; as well as a second electrode, the second electrode being disposed on the plurality of light emitting elements, The light emitting elements disposed in the overlap transfer region include a light emitting element on the first electrode that overlaps with the bank pattern and a light emitting element on the first electrode that has a portion that does not overlap with the bank pattern. 17 . The display device according to claim 16 , wherein the number of the plurality of light emitting elements disposed in the overlap transfer region is within a range of 1% to 10% of the total number of the plurality of light emitting elements transferred in the non-overlap transfer region and the overlap transfer region.

18. The display device according to claim 16, wherein a light emitting element on the first electrode overlapping with the bank pattern and a light emitting element on the first electrode having a portion not overlapping with the bank pattern are included in each of the overlapping transfer regions of the transfer region. 19 . The display device according to claim 16 , wherein the number of the plurality of light emitting elements disposed in the overlapped transfer region is less than or equal to the number of the plurality of light emitting elements transferred to the dummy region of the substrate.

20. The display device according to claim 16, further comprising a black matrix disposed on the second electrode to overlap with a region between the plurality of light emitting elements, The light emitting element having a portion that does not overlap with the bank pattern is disposed to overlap with a portion of the black matrix.

Images