Electroluminescent display device and method

Abstract

Disclosed is an electroluminescent display device and method. The electroluminescent display device according to an exemplary embodiment of the present invention includes a substrate including an active region having a light emitting region and a non-active region; a planarization layer disposed on the substrate; a light emitting element disposed on the planarization layer; a buffer layer disposed on the light emitting element and having a plurality of holes in a surface thereof; and a hydrogen trap layer disposed on the buffer layer. As a result, by preventing hydrogen from flowing into an oxide thin film transistor, the characteristics and reliability of the thin film transistor can be improved.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit and priority of Korean Patent Application No. 10-2021-0171910, filed in Korea on December 3, 2021, the entire contents of which are expressly incorporated herein by reference. Technical Field

[0003] This invention relates to an electroluminescent display device, and more specifically, to an electroluminescent display device and method using oxide thin-film transistors. Background Technology

[0004] Recently, as our society has entered an information-oriented era, the field of display devices for visually presenting electrical information signals has developed rapidly. Accordingly, various display devices with superior performance in terms of thinness and low power consumption are being developed.

[0005] Representative display devices include liquid crystal displays (LCDs), electrowetting displays (EWDs), and organic light-emitting diode displays (OLEDs).

[0006] Among these various display devices, electroluminescent displays, including organic light-emitting displays, are self-emissive. Unlike liquid crystal displays, which have a separate light source, they do not require a separate light source and can be manufactured to be lightweight and thin. Furthermore, electroluminescent displays offer advantages in power consumption due to their low-voltage operation, and also excel in color reproduction, response speed, viewing angle, and contrast ratio (CR). Therefore, electroluminescent displays are expected to be used in various fields.

[0007] An electroluminescent display device is constructed by using an organic material to create a light-emitting layer between two electrodes called the anode and cathode. Then, when holes from the anode are injected into the light-emitting layer and electrons from the cathode are injected into the light-emitting layer, the injected electrons and holes recombine with each other to form excitons in the light-emitting layer and emit light. Summary of the Invention

[0008] One aspect of the present invention is to provide an electroluminescent display device that blocks hydrogen from flowing into an oxide thin-film transistor.

[0009] The purpose of this invention is not limited to the above-described purpose, and other purposes not mentioned above will be clearly understood by those skilled in the art based on the following description.

[0010] An electroluminescent display device according to an exemplary embodiment of the present invention may include: a substrate, the substrate including an active region and a non-active region, the active region having a light-emitting region; a planarization layer disposed on the substrate; a light-emitting element disposed on the planarization layer; a buffer layer disposed on the light-emitting element and having a plurality of holes thereon; and a hydrogen trapping layer disposed on the buffer layer.

[0011] An electroluminescent display device according to another exemplary embodiment of the present invention may include: a planarization layer disposed on a substrate; a light-emitting element disposed on the planarization layer; a buffer layer disposed on the light-emitting element and having a plurality of holes in its surface; and a hydrogen trapping layer disposed on the buffer layer and having grooves corresponding to the holes in its surface.

[0012] The method according to the embodiment includes: forming a planarization layer on a substrate; forming a light-emitting element on the planarization layer; forming a buffer layer on the light-emitting element; forming a plurality of holes in the buffer layer; and forming a hydrogen trapping layer on the buffer layer, the hydrogen trapping layer having a plurality of grooves on its surface, each of the plurality of grooves overlapping a corresponding one of the plurality of holes.

[0013] The method described in the embodiments can be a method for manufacturing an electroluminescent display device.

[0014] Further details of the exemplary embodiments are included in the detailed description and accompanying drawings.

[0015] According to the present invention, by forming a hydrogen trap layer on the light-emitting element to block hydrogen from flowing into the oxide thin-film transistor, the characteristics and reliability of the thin-film transistor can be improved.

[0016] The effects of the present invention are not limited to those illustrated above, and include many other different effects in this application. Attached Figure Description

[0017] Figure 1 This is a block diagram of an electroluminescent display device according to a first exemplary embodiment of the present invention.

[0018] Figure 2 This is a circuit diagram of a sub-pixel of an electroluminescent display device according to a first exemplary embodiment of the present invention.

[0019] Figure 3 This is a plan view of an electroluminescent display device according to a first exemplary embodiment of the present invention.

[0020] Figure 4 It is along Figure 3 The sectional view taken from line III-III'.

[0021] Figure 5A and 5B yes Figure 4 A magnified view of part A.

[0022] Figure 6 This is a diagram illustrating the hydrogen trapping properties of aluminum.

[0023] Figures 7A to 7C This is a diagram illustrating the manufacturing process. Figure 4 A view of a portion of the display panel.

[0024] Figure 8 This is a cross-sectional view of an electroluminescent display device according to a second exemplary embodiment of the present invention.

[0025] Figure 9 yes Figure 8 A magnified view of part A.

[0026] Figure 10 This is a plan view of an electroluminescent display device according to a third exemplary embodiment of the present invention.

[0027] Figure 11 It is along Figure 10 A sectional view taken by line X-X'.

[0028] Figure 12 yes Figure 11 A magnified view of part A.

[0029] Figure 13 This is a plan view of an electroluminescent display device according to a fourth exemplary embodiment of the present invention.

[0030] Figure 14 It is along Figure 13 A sectional view taken from line XIII-XIII'.

[0031] Figure 15 yes Figure 14 A magnified view of part A. Detailed Implementation

[0032] The advantages and features of the present invention, and the methods for achieving these advantages and features, are described below with reference to the appendix. Figure 1 The exemplary embodiments described in detail will become clear. However, the invention is not limited to the exemplary embodiments disclosed herein, but will be implemented in various forms. Exemplary embodiments are provided by way of example only to enable those skilled in the art to fully understand the disclosure and scope of the invention. Therefore, the invention will be limited only by the scope of the appended claims.

[0033] The shapes, dimensions, proportions, angles, quantities, etc., shown in the accompanying drawings for the purpose of describing exemplary embodiments of the invention are merely examples, and the invention is not limited thereto. Similar reference numerals denote similar elements throughout the application. Furthermore, in the following description of the invention, detailed explanations of known related technologies may be omitted to avoid unnecessarily obscuring the subject matter of the invention. Terms such as “comprising,” “having,” and “including” as used herein are generally intended to allow for the addition of additional components, unless these terms are used in conjunction with the term “only.”

[0034] Even if not explicitly stated, the components are still interpreted as including the usual error range.

[0035] When using terms such as “on top of,” “above,” “below,” and “after” to describe the positional relationship between two parts, one or more parts may be placed between the two parts, unless these terms are used with the terms “immediately following” or “directly.”

[0036] When one element or layer is disposed "on" another element or layer, the element or layer may be disposed directly on the other element or layer or other elements or layers may be inserted between them.

[0037] Although the terms "first," "second," etc., are used to describe various components, these components are not limited by these terms. These terms are merely used to distinguish one component from other components. Therefore, within the scope of the inventive concept, the first component mentioned below can be the second component.

[0038] The same reference numerals generally denote the same elements throughout the application.

[0039] For ease of illustration, the dimensions and thickness of each component shown in the accompanying drawings are illustrated. However, the invention is not limited to the dimensions and thickness of the illustrated components.

[0040] The features of the various embodiments of the present invention may be combined or integrated with each other in part or in whole, and may be interlocked and operated in various technical ways. These embodiments may be implemented independently of each other or in association with each other.

[0041] Hereinafter, various exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

[0042] Figure 1 This is a block diagram of an electroluminescent display device according to a first exemplary embodiment of the present invention.

[0043] Reference Figure 1An electroluminescent display device 100 according to a first exemplary embodiment of the present invention may include an image processor 151, a timing controller 152, a data driver 153, a gate driver 154, and a display panel 110.

[0044] The image processor 151 can output a data signal DATA and a data enable signal DE via a data signal DATA provided from an external circuit, such as from an electroluminescent display device 100.

[0045] In addition to the data enable signal DE, the image processor 151 may also output one or more of the following: a vertical synchronization signal, a horizontal synchronization signal, and a clock signal.

[0046] The timing controller 152 receives the data signal DATA along with the data enable signal DE or a drive signal including the vertical sync signal, horizontal sync signal, and clock signal from the image processor 151. The timing controller 152 may output a gate timing control signal GDC for controlling the operating timing of the gate driver 154 and a data timing control signal DDC for controlling the operating timing of the data driver 153 based on the drive signal.

[0047] Data driver 153 samples and latches the data signal DATA provided by timing controller 152 in response to the data timing control signal DDC provided by timing controller 152, and converts the data signal DATA into a gamma reference voltage to output a gamma reference voltage. Data driver 153 can output the data signal DATA via data lines DL1 to DLn.

[0048] The gate driver 154 can output a gate signal while shifting the level of the gate voltage in response to the gate timing control signal GDC provided from the timing controller 152. The gate driver 154 can output the gate signal via gate lines GL1 to GLm.

[0049] The display panel 110 can display an image while the sub-pixels P emit light in response to data signals DATA and gate signals provided from the data driver 153 and the gate driver 154. (Refer to...) Figure 2 as well as Figure 5A and Figure 5B Describe the specific structure of subpixel P in detail.

[0050] Figure 2 It is a circuit diagram of a sub-pixel included in an electroluminescent display device according to a first exemplary embodiment of the present invention.

[0051] Reference Figure 2According to the first exemplary embodiment of the present invention, the sub-pixels of the electroluminescent display device 100 may include a switching transistor ST, a driving transistor DT, a compensation circuit 135, and a light-emitting element 130.

[0052] The light-emitting element 130 can operate according to the drive current generated by the drive transistor DT to emit light.

[0053] The switching transistor ST can perform a switching operation to store a data signal provided via data line 117 in response to a gate signal provided via gate line 116 as a data voltage in a capacitor.

[0054] The drive transistor DT can operate in response to the data voltage stored in the capacitor so that a constant drive current flows between the high-potential power line VDD and the low-potential power line GND.

[0055] The compensation circuit 135 is a circuit used to compensate for the threshold voltage, etc., of the driving transistor DT, and the compensation circuit 135 may include one or more thin-film transistors and a capacitor. The construction of the compensation circuit 135 may be changed depending on the compensation method.

[0056] Examples Figure 2 The sub-pixel shown is configured as a 2T1C structure having two transistors and one capacitor, including a switching transistor ST, a driving transistor DT, a capacitor, and a light-emitting element 130. However, when a compensation circuit 135 is added, the sub-pixel can have various structures, such as 3T1C, 4T2C, 5T2C, 6T1C, 6T2C, 7T1C, and 7T2C structures.

[0057] Figure 3 This is a plan view of an electroluminescent display device according to a first exemplary embodiment of the present invention.

[0058] Figure 4 It is along Figure 3 The sectional view taken from line III-III'.

[0059] Figure 5A and 5B yes Figure 4 A magnified view of part A.

[0060] Figure 4 The example illustrates a scenario where a touch unit or touch circuit is included in the display panel 110, but the invention is not limited thereto.

[0061] Figure 5A yes Figure 4 An enlarged sectional view of part A. Figure 5B It is shown Figure 5A A plan view of the upper surface.

[0062] Reference Figure 3 An electroluminescent display device 100 according to a first exemplary embodiment of the present invention may include a display panel 110, a flexible film, and a printed circuit board.

[0063] Display panel 110 is a panel used to display images to the user.

[0064] The display panel 110 may include display elements for displaying images, driving elements for driving the display elements, and lines for transmitting various signals to the display elements and driving elements. The display elements may be implemented differently depending on the type of the display panel 110. For example, when the display panel 110 is an organic light-emitting display panel, the display elements are organic light-emitting elements that include an anode, an organic light-emitting layer, and a cathode.

[0065] In the following description, it is assumed that the display panel 110 is an organic light-emitting display panel, but the display panel 110 is not limited to organic light-emitting display panels.

[0066] The display panel 110 may include an active area AA and an passive area NA.

[0067] The active area AA is the area on the display panel 110 where the image is displayed.

[0068] Multiple sub-pixels belonging to multiple pixels and circuitry for driving the multiple sub-pixels can be disposed in an active region AA. Multiple sub-pixels belong to the active region AA, and corresponding display elements can be disposed in each of the multiple sub-pixels. A group of multiple sub-pixels (e.g., four sub-pixels) can constitute one pixel among the multiple pixels. For example, a corresponding organic light-emitting element including an anode, an organic light-emitting layer, and a cathode can be disposed in each of the multiple sub-pixels, but the invention is not limited thereto. Furthermore, the circuitry for driving the multiple sub-pixels can include driving elements, lines, etc. For example, the circuitry can include thin-film transistors, storage capacitors, gate lines, data lines, etc., but the invention is not limited thereto.

[0069] The non-active region (NA) is the area in which no image is displayed.

[0070] Figure 3 The diagram illustrates the non-active region NA adjacent to and surrounding the four sides of the rectangular active region AA, but the shapes and arrangements of the active region AA and the non-active region NA are not limited to these. Figure 3 The example shown.

[0071] The active area AA and the passive area NA can have shapes suitable for designing electronic devices on which the electroluminescent display device 100 is mounted. For example, another example shape of the active area AA can be pentagonal, hexagonal, circular, or elliptical.

[0072] Various lines and circuits for driving the organic light-emitting elements in the active region AA can be arranged in the non-active region NA. For example, in the non-active region NA, driver integrated circuits (ICs) such as gate driver ICs and data driver ICs or link lines for transmitting signals to multiple sub-pixels and circuits in the active region AA can be provided, but the present invention is not limited thereto.

[0073] at the same time, Figure 3 The left and right sides can be defined as the gate pad portions on which the gate driver IC is disposed. Figure 3 The lower side can be defined as the data pad portion for connecting the flexible membrane, but the present invention is not limited thereto.

[0074] Electroluminescent display devices may include various additional components for generating various signals or driving pixels in the active area AA. Additional components for driving pixels may include inverter circuits, multiplexers, electrostatic discharge (ESD) circuits, etc. Electroluminescent display devices may also include additional components associated with functions other than driving pixels. For example, an electroluminescent display device may include additional components providing touch sensing functionality, user authentication functionality (e.g., fingerprint recognition), multi-level pressure sensing functionality, haptic feedback functionality, etc. These additional components may be located in the non-active area NA and / or in external circuitry connected to a connection interface.

[0075] Although not shown, the flexible film is used to provide signals to multiple sub-pixels and circuits in the active area AA, and can be electrically connected to the display panel 110. The flexible film can be disposed at one end of the non-active area NA of the display panel 110, and provides power supply voltage, data voltage, etc. to multiple sub-pixels and circuits in the active area AA. For example, a driver IC such as a data driver IC can be disposed on the flexible film.

[0076] A printed circuit board (PCB) can be disposed at a corresponding end of the flexible film and connected to the flexible film. The PCB is a component that provides signals to the driver IC. The PCB can provide various signals to the driver IC, such as drive signals and data signals.

[0077] Meanwhile, the superior characteristics of the display panel are ensured by using oxide thin-film transistors with high mobility and low off-current.

[0078] However, when SiOx or SiNx is deposited as a protective layer primarily used in oxide thin-film transistors (TFTs), hydrogen from the protective layer can flow into the TFT. Hydrogen can ion-bond with oxygen in the TFT to act as a shallow donor, or it can enter oxygen vacancies that serve as electron trap centers. This increases the difficulty of controlling the on-state voltage (Von) and off-state voltage (Voff) of the TFT.

[0079] Therefore, one feature of the present invention is that hydrogen is prevented from flowing into the thin-film transistor by utilizing the hydrogen trapping properties of aluminum.

[0080] Therefore, a feature of the first exemplary embodiment of the present invention is that a hydrogen trapping layer 150 is formed on the light-emitting element to prevent hydrogen from flowing into the oxide thin-film transistor. This improves the characteristics and reliability of the thin-film transistor.

[0081] Reference Figure 4 as well as Figure 5A and 5B The substrate 111 may include an active region AA and a non-active region NA that is adjacent to and located outside the active region AA.

[0082] Thin-film transistor 120, light-emitting element 130, and encapsulation layer (not shown) may be formed in the active region AA of substrate 111.

[0083] The substrate 111 is used to support and protect the components of the electroluminescent display device disposed thereon.

[0084] Recently, flexible substrates 111 can use flexible materials with flexible properties, such as plastics.

[0085] The flexible substrate 111 may be in the form of a film comprising one of the following: polyester-based polymers, silicone-based polymers, acrylic polymers, polyolefin-based polymers, and copolymers thereof.

[0086] The touch sensor 119 can be disposed on the substrate 111.

[0087] The buffer layer 115a may be disposed on the substrate 111 on which the touch sensor 119 is disposed.

[0088] The buffer layer 115a can be formed in a structure in which a single insulating layer or multiple insulating layers are stacked sequentially to block impurities, including moisture and oxygen, from flowing in from the substrate 111. That is, the buffer layer 115a can be formed from a single layer or multiple layers of an inorganic insulating material such as silicon oxide (SiOx), silicon nitride (SiNx), or aluminum oxide (AlOx). Depending on the type of thin-film transistor 120, the buffer layer 115a may be omitted in some embodiments.

[0089] The buffer layer 115a may include a contact hole that exposes a portion of the touch sensor 119.

[0090] The light blocking layer 125 can be disposed on the buffer layer 115a.

[0091] The light-blocking layer 125 may be formed of a metal material with light-blocking function in order to block external light from being introduced into the semiconductor layer 124.

[0092] The light-blocking layer 125 can be formed as a single layer or multilayer structure of any opaque metal or alloy thereof, such as aluminum (Al), chromium (Cr), tungsten (W), titanium (Ti), nickel (Ni), neodymium (Nd), molybdenum (Mo) and copper (Cu).

[0093] The first capacitor electrode 126 and the data line 117 can be disposed on the buffer layer 115a.

[0094] In addition, a first touch electrode 129 electrically connected to the touch sensor 119 may be disposed on the buffer layer 115a.

[0095] The first insulating layer 115b may be disposed on the light blocking layer 125, the first capacitor electrode 126, the data line 117, and the first touch electrode 129.

[0096] In this case, the first insulating layer 115b may include a contact hole that exposes a portion of the first touch electrode 129 and the light blocking layer 125.

[0097] The first insulating layer 115b may be formed from a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx).

[0098] The thin-film transistor 120 may be disposed on the first insulating layer 115b. In this case, the thin-film transistor 120 may include a gate 121, a source 122, a drain 123, and a semiconductor layer 124.

[0099] Semiconductor layer 124 can be formed of oxide semiconductor. Oxide semiconductor has excellent mobility and uniformity characteristics. At this point, the oxide semiconductor can be a quaternary metal oxide, such as a material based on indium gallium tin zinc oxide (InSnGaZnO); a ternary metal oxide, such as a material based on indium gallium zinc oxide (InGaZnO), a material based on indium tin zinc oxide (InSnZnO), a material based on indium aluminum zinc oxide (InAlZnO), a material based on tin gallium zinc oxide (SnGaZnO), a material based on aluminum gallium zinc oxide (AlGaZnO), and a material based on tin aluminum zinc oxide (SnAlZnO); or a binary metal oxide, such as a material based on indium zinc oxide (InZnO), a material based on tin zinc oxide (SnZnO), a material based on aluminum zinc oxide (AlZnO), a material based on zinc magnesium oxide (ZnMgO), a material based on tin magnesium oxide (SnMgO), a material based on indium magnesium oxide (InMgO), and a material based on indium gallium oxide (InGaO); or a monometallic metal oxide, such as a material based on indium oxide (InO), a material based on tin oxide (SnO), and a material based on zinc oxide (ZnO). The composition ratio of each element is not restricted.

[0100] The semiconductor layer 124 may include a source region having p-type or n-type impurities, a drain region, and a channel region located between the source region and the drain region, and may further include a low-concentration doped region located between the source region and the drain region adjacent to the channel region.

[0101] The source and drain regions are regions doped with a high concentration of impurities and can be connected to the source 122 and drain 123 of the thin-film transistor 120, respectively.

[0102] As impurity ions, either p-type or n-type impurities can be used. P-type impurities can be one of boron (B), aluminum (Al), gallium (Ga), and indium (In), while n-type impurities can be one of phosphorus (P), arsenic (As), and antimony (Sb).

[0103] The channel region can be doped with n-type or p-type impurities depending on the NMOS or PMOS transistor structure.

[0104] The second insulating layer 115c is a gate insulating layer composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx), and can be disposed above the semiconductor layer 124 so that the current flowing through the semiconductor layer 124 does not flow into the gate 121. Silicon oxide has weaker ductility than metals, but better ductility than silicon nitrides, and can therefore be formed into a single layer or multiple layers depending on its properties.

[0105] The gate 121 serves as a switch to turn the thin-film transistor 120 on or off based on an electrical signal transmitted from the outside via the gate line, and may be composed of a single layer or multiple layers of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), or their alloys. However, the present invention is not limited thereto.

[0106] In this case, the source 122 and the drain 123 may be composed of a single layer or multiple layers of conductive metals such as aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu) or their alloys, but the present invention is not limited thereto.

[0107] One side of the drain 123 can be electrically connected to the semiconductor layer 124, and the other side of the drain 123 can be electrically connected to the light blocking layer 125.

[0108] The second capacitor electrode 136 formed by the semiconductor layer 124 may be disposed on the first insulating layer 115b above the first capacitor electrode 126.

[0109] The second capacitor electrode 136 and the first capacitor electrode 126 can form a first storage capacitor with a first insulating layer 115b inserted between them.

[0110] Meanwhile, the second touch electrode 139, which is electrically connected to the first touch electrode 129, can be disposed on the first insulating layer 115b of the non-active region NA.

[0111] In addition, the first pad electrode 128 may be disposed on the first insulating layer 115b of the non-active region NA.

[0112] The passivation layer 115d may be disposed on the thin-film transistor 120 and the second touch electrode 139. The passivation layer 115d may be formed of an inorganic insulating layer such as silicon oxide (SiOx) or silicon nitride (SiNx).

[0113] The passivation layer 115d can be used to prevent unnecessary electrical connections between components disposed above and below it, and to prevent contamination or damage from the outside. Depending on the construction and characteristics of the thin-film transistor 120 and the light-emitting element 130, the passivation layer 115d may be omitted.

[0114] The structure of the thin-film transistor 120 can be classified into inverted staggered structures and coplanar structures based on the position of the components constituting the thin-film transistor 120. For example, in a thin-film transistor with an inverted staggered structure, the gate may be located on the side opposite to the source and drain relative to the semiconductor layer. Figure 4As shown, in a thin-film transistor 120 with a coplanar structure, the gate 121 may be located on the same side as the source 122 and the drain 123 relative to the semiconductor 124.

[0115] although Figure 4 A thin-film transistor 120 with a coplanar structure is shown, but an electroluminescent display device according to a first exemplary embodiment of the present invention may include thin-film transistors with an anti-interlaced structure.

[0116] For ease of illustration, only the driving thin-film transistor 120, which may be included among the various thin-film transistors in the electroluminescent display device, is shown, but other switching thin-film transistors and compensation circuitry may also be included in the electroluminescent display device.

[0117] The switching thin-film transistor can transmit a signal from the data line 117 to the gate 121 of the driving thin-film transistor 120 when a signal is applied from the gate line. The driving thin-film transistor 120 can transmit current via the power line according to the signal received from the switching thin-film transistor to the anode 131, and the emission of light can be controlled by the current transmitted to the anode 131.

[0118] A planarization layer 115e may be disposed on the thin-film transistor 120 to protect the thin-film transistor 120 and alleviate the step caused by the thin-film transistor 120, and reduce the parasitic capacitance generated between the thin-film transistor 120, the gate line, the data line 117 and the light-emitting element 130.

[0119] The planarization layer 115e may be formed from one or more materials selected from acrylic resin, epoxy resin, phenolic resin, polyamide resin, polyimide resin, unsaturated polyester resin, polystyrene resin, polyphenylene sulfide resin and phenylcyclobutene, but the present invention is not limited thereto.

[0120] A planarization layer or buffer layer may be further disposed on the planarization layer 115e.

[0121] The buffer layer can be formed by multiple layers of silicon oxide (SiOx) and protects the components disposed on the planarization layer 115e. Depending on the structure and characteristics of the thin-film transistor 120 and the light-emitting element 130, the buffer layer may be omitted.

[0122] When a planarization layer is additionally disposed on planarization layer 115e, anode 131 can be electrically connected to thin-film transistor 120 via intermediate electrode.

[0123] Meanwhile, the planarization layer 115e above the second capacitor electrode 136 can be removed to form an anode hole, but the present invention is not limited thereto.

[0124] The insulating layer below the passivation layer 115d may be configured to extend to the end of the substrate 111 in the non-active region NA, and the passivation layer 115d may be configured to extend to a portion of the non-active region NA, but the invention is not limited thereto. Furthermore, the planarization layer 115e may be configured to extend to a portion of the non-active region NA and may expose a portion of the passivation layer 115d, but the invention is not limited thereto.

[0125] The side surface of the planarization layer 115e, which extends to a portion of the non-active region NA, may be inclined, but the invention is not limited thereto.

[0126] A light-emitting element 130, including an anode 131, a light-emitting unit or structure 132, and a cathode 133, can be disposed on a planarization layer 115e.

[0127] Anode 131 can be disposed on planarization layer 115e.

[0128] The anode 131 is an electrode used to provide holes to the light-emitting unit 132 and can be connected to the thin-film transistor 120 via a contact hole in the planarization layer 115e.

[0129] The anode 131 may be formed from indium tin oxide (ITO), indium zinc oxide (IZO), or other materials that are transparent conductive materials, but the present invention is not limited thereto.

[0130] For example, a first exemplary embodiment of the present invention may be a bottom-emitting type that emits light to the lower part where the anode 131 is provided, but the present invention is not limited thereto.

[0131] One side of the anode 131 may extend to the anode hole, and a second capacitor may be formed therebetween with a passivation layer 115d inserted between it and the second capacitor electrode 136 below it, but the present invention is not limited thereto.

[0132] The second pad electrode 118 can be disposed on the first pad electrode 128 in the non-active region NA and can be electrically connected to the first pad electrode 128.

[0133] The embankment 115f can be set on the anode 131 and the planarization layer 115e.

[0134] The embankment 115f provided on the anode 131 and the planarization layer 115e may have openings where the corresponding sub-pixels are located. These openings belong to the areas where light emission occurs, namely the light emission area EA.

[0135] After photoresist is formed on the anode 131, the embankment 115f can be formed through a photolithography process. Photoresist refers to a photosensitive resin whose solubility in a developer changes due to the action of light, and specific patterns can be obtained by exposing and developing the photoresist. Photoresist can be divided into positive photoresist and negative photoresist. In this case, positive photoresist refers to photoresist whose solubility in the developer increases due to exposure, and when positive photoresist is developed, a pattern is obtained where the exposed portion is removed. Negative photoresist refers to photoresist whose solubility in the developer decreases due to exposure, and when negative photoresist is developed, a pattern is obtained where the unexposed portion is removed.

[0136] The light-emitting unit 132 of the light-emitting element 130 can be formed by using a fine metal mask (FMM) as a deposition mask.

[0137] In addition, to prevent damage that may result from contact with the deposition mask set on the dike 115f and to maintain a constant distance between the dike 115f and the deposition mask, a spacer formed of one of the following transparent organic materials, namely benzocyclobutene, photoacrylic, and polyimide, may be provided on the dike 115f.

[0138] The dam 115f may include an opening that exposes a portion of the anode 131 by removing a portion of the dam 115f in the light-emitting area.

[0139] The embankment 115f may be configured to extend into a portion of the non-active NA and may be inclined along the inclined side surface of the planarization layer 115e, but the invention is not limited thereto.

[0140] Meanwhile, a portion of the embankment 115f adjacent to the inclined side surface of the embankment 115f can be removed to expose the passivation layer 115d.

[0141] The light-emitting unit 132 can be disposed between the anode 131 and the cathode 133.

[0142] The light-emitting unit 132 for emitting light may include at least one layer of a hole injection layer (HIL), a hole transport layer (HTL), a light-emitting layer, an electron transport layer (ETL), and an electron injection layer (EIL), and some components may be omitted depending on the structure or characteristics of the electroluminescent display device. Here, an electroluminescent layer and an inorganic light-emitting layer may also be used as the light-emitting layer.

[0143] A hole injection layer is disposed on the anode 131 and is used to facilitate hole injection.

[0144] The hole transport layer is disposed on the hole injection layer and is used to smoothly transport holes to the light-emitting layer.

[0145] The light-emitting layer is disposed on the hole transport layer and includes a material capable of emitting light of a specific color, thereby emitting light of a specific color. Furthermore, phosphorescent or fluorescent materials can be used to form the light-emitting material.

[0146] An electron injection layer may be further disposed on the electron transport layer. The electron injection layer is an organic layer that promotes the injection of electrons from the cathode 133, and may be omitted depending on the structure and characteristics of the electroluminescent display device.

[0147] Meanwhile, by further providing an electron blocking layer or hole blocking layer at a position adjacent to the light-emitting layer to block the flow of electrons or holes, it is possible to prevent electrons from migrating from the light-emitting layer and passing through the adjacent hole transport layer when injected into the light-emitting layer, or to prevent holes from migrating from the light-emitting layer and passing through the adjacent electron transport layer when injected into the light-emitting layer, thereby improving the luminous efficiency.

[0148] The light-emitting unit 132 may be configured to extend into a portion of the non-active region NA and may be inclined along the inclined side surface of the embankment 115f, but the invention is not limited thereto.

[0149] The light-emitting unit 132 may be tilted along the inclined side surface of the embankment 115f, but the present invention is not limited thereto.

[0150] A cathode 133 is disposed on the light-emitting unit 132 and is used to provide electrons to the light-emitting unit 132. Since the cathode 133 provides electrons, it can be formed of a metallic material such as magnesium or a silver-magnesium alloy, which is a conductive material with a low work function, but the present invention is not limited thereto.

[0151] The cathode 133 may be configured to extend into a portion of the non-active region NA to cover the light-emitting unit 132, but the invention is not limited thereto.

[0152] The cathode 133 may be tilted along the inclined side surface of the light-emitting unit 132, but the present invention is not limited thereto.

[0153] The buffer layer 140 can be disposed on the cathode 133.

[0154] Multiple holes 145 may be formed in the surface of the buffer layer 140.

[0155] Multiple pores 145 formed in the surface of the buffer layer 140 can be used as seeds, in which defects are generated and grow in the hydrogen trapping layer 150 deposited on the buffer layer 140.

[0156] Since the light-emitting unit 132 is easily damaged by external heat or chemicals, multiple holes 145 can be formed in the surface of the buffer layer 140 using a laser.

[0157] When multiple holes 145 are formed in the surface of the buffer layer 140 by laser etching, they may have a circular shape when viewed from above, but the invention is not limited thereto.

[0158] In order not to damage the cathode 133 and the light-emitting unit 132, the buffer layer 140 may be formed to have a thickness of at least 1 μm.

[0159] The buffer layer 140 may be formed of an insulating material that does not allow hydrogen to pass through, has excellent adhesion to the hydrogen trapping layer 150 and the aluminum of the cathode 133, and may include, for example, aluminum oxide. Thus, the buffer layer 140 can prevent hydrogen trapped in the hydrogen trapping layer 150 above it from flowing into the oxide thin-film transistor 120 below it.

[0160] The buffer layer 140 may be configured to extend into a portion of the non-active region NA to cover the cathode 133, but the invention is not limited thereto. The buffer layer 140 may be inclined along the inclined side surface of the cathode 133 or may have an inclination along the inclined side surface of the cathode 133, but the invention is not limited thereto. It should be understood that "coverage" includes the meaning of complete coverage and partial coverage.

[0161] A hydrogen trap layer 150 may be disposed on a buffer layer 140 in which a plurality of holes 145 are formed.

[0162] The hydrogen trapping layer 150 may be formed of an aluminum layer with dislocations and point defects to enhance the hydrogen trapping characteristics between the cathode 133 and the encapsulation layer.

[0163] Hydrogen atoms adsorbed through transfer between aluminum atoms can diffuse and be trapped in trap sites, such as dislocations, grain boundaries, and oxygen vacancies, where the energy determines the most stable position.

[0164] Figure 6 This is a diagram illustrating the hydrogen trapping properties of aluminum.

[0165] Reference Figure 6 a) represents an interstitial site, b) represents a surface, and c) represents a subsurface. Additionally, d) represents a grain boundary, e) represents a dislocation, and f) represents an oxygen vacancy.

[0166] Oxygen atoms of size 1.06 Å diffuse between aluminum atoms of size approximately 2.86 Å and are trapped in trap positions a) to e) based on energy as the most stable position.

[0167] However, in general, aluminum has the characteristic of not forming hydrogen trap sites well during deposition and aluminum is deposited with high quality.

[0168] Therefore, a feature of the first exemplary embodiment of the present invention is that a hydrogen trapping layer 150 is formed on a buffer layer 140 in which a plurality of holes 145 are formed to generate and grow defects, thereby increasing hydrogen trapping sites such as misalignments and point defects in the hydrogen trapping layer 150 in the direction perpendicular to the holes 145. Thus, by preventing hydrogen from flowing into the oxide thin-film transistor 120, the characteristics and reliability of the thin-film transistor 120 can be improved.

[0169] In other words, in the process of forming a thin film on a substrate, particles reach its surface and then move along the surface of the substrate using the energy retained in their atoms, thereby performing surface diffusion. Subsequently, chemical bonds are formed between the atoms through interaction with atoms on the surface, thereby forming a first atomic layer. In this way, all the atoms on the surface combine with the deposited atoms, thereby forming the first atomic layer. The above steps can then be repeated to form second and subsequent atomic layers.

[0170] Simultaneously, when defects such as holes 145 are formed in the surface of the buffer layer 140, if the deposition continues while atomic layers are formed inside the holes 145 according to the thin film formation process, the atomic layers formed on the corresponding surfaces of the buffer layer 140 (including inside the holes 145) meet each other. These atoms break away from the existing regular atomic arrangement and recombine with each other, thereby depositing a hydrogen trap layer 150, causing these atoms to twist, that is, to generate and grow defects in the upward direction (L) (see...). Figure 5A ).

[0171] When a defect, such as hole 145, is formed at the location of the defect in the surface of the buffer layer 140, the surface of the buffer layer 140, i.e., its upper surface, may have an uneven shape. For example... Figure 5A As shown, the lower surface of the hydrogen trapping layer 150 is formed along the upper surface of the buffer layer 140, which has an uneven shape, and the upper surface of the hydrogen trapping layer 150 may have a shape including multiple recesses. Multiple recesses may be formed at locations corresponding to the holes 145. For example... Figure 5B As shown, when multiple recesses, i.e. grooves 155, are formed in the upper surface of the hydrogen trap layer 150, the number of hydrogen trap locations, such as misalignments and point defects, increases.

[0172] The hydrogen trap layer 150 may be configured to extend into a portion of the non-active region NA to cover the buffer layer 140, but the invention is not limited thereto. It should be understood that "coverage" includes both complete and partial coverage.

[0173] The hydrogen trap layer 150 may be inclined along the inclined side surface of the buffer layer 140 or have an inclined portion along the inclined side surface of the buffer layer 140, but the present invention is not limited thereto.

[0174] Meanwhile, although not shown, an encapsulation layer may be configured on the upper part of the hydrogen trap layer 150 to prevent the light-emitting element 130 and thin-film transistor 120, which are components of the electroluminescent display device, from being oxidized or damaged by moisture, oxygen or impurities flowing in from the outside.

[0175] The encapsulation layer may consist of multiple layers and may include a first inorganic material layer, a second inorganic material layer, and an organic material layer, but the present invention is not limited thereto.

[0176] Figures 7A to 7C This is a diagram illustrating the manufacturing process. Figure 4 A view of a portion of the display panel.

[0177] Figures 7A to 7C Only shown in Figure 4 The process of forming a buffer layer 140 and a hydrogen trapping layer 150 during the manufacturing process of the display panel is taken as an example.

[0178] Reference Figure 7A The buffer layer 140 of the present invention can be formed on the cathode 133.

[0179] The buffer layer 140 may be deposited on the entire surface of the cathode 133 to cover the cathode 133, and in order not to damage the cathode 133 and the light-emitting unit 132 below it, the buffer layer 140 may be formed to have a thickness of at least 1 μm.

[0180] The buffer layer 140 may be formed to extend into a portion of the non-active region NA to cover the cathode 133, but the invention is not limited thereto. The buffer layer 140 may be inclined along the inclined side surface of the cathode 133, but the invention is not limited thereto.

[0181] The buffer layer 140 may be formed of an insulating material that does not allow hydrogen to pass through, has excellent adhesion to the aluminum of the hydrogen trapping layer 150 and the cathode 133, and may be formed, for example, of aluminum oxide.

[0182] Then, refer to Figure 7B Multiple holes 145 can be formed on the surface of the buffer layer 140 by irradiating the buffer layer 140 with a laser.

[0183] In other words, since the light-emitting unit 132 is easily damaged by external heat or chemicals, a laser can be used to form multiple holes 145 in the surface of the buffer layer 140.

[0184] Multiple holes 145 can be formed perpendicular to the laser direction and can be formed in a checkerboard shape when viewed from above or on a plane. In this case, for example, the distance between the holes 145 is equal in width and length, and can be 0.5 μm or less, and their vertical distance can be 0.5 μm or less. It should be understood that "checkerboard shape" includes an array having multiple rows of holes 145. Multiple rows can extend in a first direction and can be arranged in a second direction perpendicular to the first direction. In some embodiments, the holes 145 in adjacent rows are aligned along the second direction. In some embodiments, the holes 145 in adjacent rows are not aligned along the second direction, but are offset or misaligned from each other, for example. Other arrangements may also be included in some embodiments. For example, the multiple rows of holes 145 can be arranged in a wavy or S-shaped pattern along the first direction, or can be arranged in a zigzag pattern along the first direction. In some embodiments, the holes 145 are arranged non-periodicly or randomly, that is, with a non-uniform distance for separating corresponding adjacent pairs of holes 145. The non-uniform distance can be greater than a selected distance to avoid the merging of adjacent holes 145 and thus degrade performance. It should be recognized that, in order to achieve the technical advantage of increasing the number of hydrogen trap locations in the hydrogen trap layer 150, a wide range of the number of holes 145 will be in line with the technical advantage, and many arrangement types of holes 145 will be in line with the technical advantage.

[0185] When a plurality of holes 145 are formed in the surface of the buffer layer 140 by laser etching, each of the plurality of holes 145 may have a circular shape when viewed from above, but the invention is not limited thereto. For example, each of the plurality of holes 145 may have an elliptical shape, and the shapes of the plurality of holes 145 may be slightly different from each other.

[0186] In the case of the first exemplary embodiment of the present invention, a plurality of holes 145 may be formed in the entire surface of the buffer layer 140, but the present invention is not limited thereto.

[0187] Then, refer to Figure 7C The hydrogen trap layer 150 can be formed on a buffer layer 140 in which a plurality of pores 145 are formed.

[0188] The hydrogen trap layer 150 may be deposited on the entire surface of the buffer layer 140 to cover the buffer layer 140 underneath, and may be set to have a thickness greater than or equal to the vertical length of the hole 145, i.e., 0.5 μm or greater.

[0189] The hydrogen trap layer 150 may be configured to extend into a portion of the non-active region NA to cover the buffer layer 140, but the invention is not limited thereto.

[0190] The hydrogen trap layer 150 may be tilted along the inclined side surface of the buffer layer 140, but the invention is not limited thereto.

[0191] When viewed in cross-section, the "V"-shaped groove 155 may correspond to the hole 145 formed in the surface of the hydrogen trap layer 150 below it (or the groove 155 formed in the surface of the hydrogen trap layer 150 corresponding to the hole 145 has a "V"-shaped cross-section), but the invention is not limited thereto. It should be understood that the "V" shape includes the meaning of a shape having a transition from shorter at the top to narrower at the bottom. For example, in Figure 5A In this design, the groove 155 is wider along the vertical axis when it is farther from the buffer layer 140 and narrower when it is closer to the buffer layer 140. While still maintaining the "V" shape, the sidewalls of the groove 155 can be straight, curved, or a combination thereof, as shown in the figure.

[0192] Meanwhile, in this invention, multiple holes can be formed on the entire surface of the buffer layer, excluding the light-emitting area, as shown in the reference. Figure 8 and 9 This will be described in detail.

[0193] Figure 8 This is a cross-sectional view of an electroluminescent display device according to a second exemplary embodiment of the present invention.

[0194] Figure 9 yes Figure 8 A magnified view of part A.

[0195] Figure 8 and 9 The second exemplary implementation is the same as described above. Figures 3 to 5A The only difference from the first exemplary embodiment of 5B is the location of the plurality of holes 245 formed in the buffer layer 1240; the other constructions are substantially the same, and therefore repeated descriptions will be omitted. The same reference numerals are used for the same components.

[0196] Figure 8 The illustration shows a case where a touch unit is included in the display panel 210, but the invention is not limited thereto.

[0197] Figure 9 yes Figure 8 An enlarged sectional view of part A.

[0198] Reference Figure 8 and 9 The light-emitting element 130, including an anode 131, a light-emitting unit 132, and a cathode 133, can be disposed on the planarization layer 115e.

[0199] The anode 131 may be formed from indium tin oxide (ITO), indium zinc oxide (IZO), or other materials that are transparent conductive materials, but the present invention is not limited thereto.

[0200] For example, a second exemplary embodiment of the present invention may be a bottom-emitting type that emits light toward the lower part where the anode 131 is provided, but the present invention is not limited thereto.

[0201] The embankment 115f can be set on the anode 131 and the planarization layer 115e.

[0202] The embankment 115f provided on the anode 131 and the planarization layer 115e may have an opening where the corresponding sub-pixel is located. The opening belongs to the area where light emission occurs, i.e., the light emission area EA.

[0203] The embankment 115f may be configured to extend into a portion of the non-active region NA and may be inclined along the inclined side surface of the planarization layer 115e, but the invention is not limited thereto.

[0204] Meanwhile, a portion of the embankment 115f adjacent to the inclined side surface of the embankment 115f can be removed to expose the passivation layer 115d.

[0205] The light-emitting unit 132 can be disposed between the anode 131 and the cathode 133.

[0206] The light-emitting unit 132 may be configured to extend into a portion of the non-active region NA and may be inclined along the inclined side surface of the embankment 115f, but the invention is not limited thereto.

[0207] The light-emitting unit 132 may be tilted along the inclined side surface of the embankment 115f, but the present invention is not limited thereto.

[0208] A cathode 133 is disposed on the light-emitting unit 132 and is used to provide electrons to the light-emitting unit 132. Since the cathode 133 needs to provide electrons, it can be formed of a metallic material such as magnesium or a silver-magnesium alloy, which is a conductive material with a low work function, but the present invention is not limited thereto.

[0209] In the case of bottom-emitting type, the metallic material constituting the cathode 133 may include a material with excellent reflectivity, but the present invention is not limited thereto.

[0210] The cathode 133 may be configured to extend into a portion of the non-active region NA to cover the light-emitting unit 132, but the invention is not limited thereto.

[0211] The cathode 133 may be tilted along the inclined side surface of the light-emitting unit 132, but the present invention is not limited thereto.

[0212] According to a second exemplary embodiment of the present invention, the buffer layer 240 may be disposed on the cathode 133.

[0213] Multiple holes 245 may be formed in the surface of the buffer layer 240, excluding the light-emitting area EA. It should be understood that "excluding the light-emitting area EA" is not limited to excluding only the light-emitting area EA. Figure 9 As shown, the light-emitting area EA can extend between the sidewalls of the embankment 115f. In some embodiments, for example due to process variations, when the location of one or more holes 145 of the buffer layer 240 extends slightly beyond the sidewall of the embankment 115f, the area other than the light-emitting area EA may slightly overlap with the light-emitting area EA. In some embodiments, for example when the location of one or more holes 145 of the buffer layer 240 does not extend all the way to the sidewall of the embankment 115f, the area other than the light-emitting area EA may not include an area slightly larger than the light-emitting area EA.

[0214] When forming holes 245 in the buffer layer 240 using a laser, laser etching is performed on the remaining surface of the buffer layer 240, except for the light-emitting area EA, rather than on the entire surface of the buffer layer 240, to prevent non-light emission due to damage to the light-emitting unit 132, which is susceptible to external impact. In this case, non-light emission is prevented, thereby improving yield and display quality.

[0215] When multiple holes 245 are formed in the surface of the buffer layer 240 by laser etching, they may have a circular shape when viewed from above, but the invention is not limited thereto.

[0216] In order not to damage the cathode 133 and the light-emitting unit 132, the buffer layer 240 may be formed to have a thickness of at least 1 μm.

[0217] The buffer layer 240 may be formed of an insulating material that does not allow hydrogen to pass through, has excellent adhesion to the aluminum of the hydrogen trapping layer 150 and the cathode 133, and may be formed, for example, of aluminum oxide. Thus, the buffer layer 240 can prevent hydrogen trapped in the hydrogen trapping layer 150 above it from flowing into the oxide thin-film transistor 120 below it.

[0218] The buffer layer 240 may be configured to extend into a portion of the non-active region NA to cover the cathode 133, but the invention is not limited thereto. The buffer layer 240 may be inclined along the inclined side surface of the cathode 133, but the invention is not limited thereto.

[0219] The hydrogen trap layer 250 can be disposed on the buffer layer 240 in which a plurality of holes 245 are formed.

[0220] The hydrogen trapping layer 250 may be formed of an aluminum layer with dislocations and point defects to enhance the hydrogen trapping characteristics between the cathode 133 and the encapsulation layer.

[0221] The hydrogen trap layer 250 may be configured to extend into a portion of the non-active region NA to cover the buffer layer 240, but the invention is not limited thereto.

[0222] The hydrogen trap layer 250 may be tilted along the inclined side surface of the buffer layer 240, but the invention is not limited thereto.

[0223] When viewed in cross-section, a "V"-shaped groove 255 may correspond to a hole 245 formed in the surface of the hydrogen trap layer 250 below it, but the invention is not limited thereto.

[0224] Meanwhile, in this invention, the buffer layer may be formed only in the area other than the light-emitting area, referring to... Figures 10 to 12 This will be described in detail.

[0225] Figure 10 This is a plan view of an electroluminescent display device according to a third exemplary embodiment of the present invention.

[0226] Figure 11 It is along Figure 10 A sectional view taken by line X-X'.

[0227] Figure 12 yes Figure 11 A magnified view of part A.

[0228] Figures 10 to 12 The third exemplary implementation is the same as described above. Figure 8 and 9 The second exemplary embodiment differs only in the location where the buffer layer 340 is formed; the rest of the construction is substantially the same, and therefore repeated descriptions will be omitted. The same reference numerals are used for the same components.

[0229] Figure 11 The illustration shows a case where a touch unit is included in the display panel 310, but the invention is not limited thereto.

[0230] Figure 12 yes Figure 11 An enlarged sectional view of part A.

[0231] Reference Figures 10 to 12 In the electroluminescent display device 300 according to the third exemplary embodiment of the present invention, the buffer layer 340 according to the third exemplary embodiment of the present invention may be disposed on the cathode 133.

[0232] The buffer layer 340 may be formed only in the area excluding the light-emitting area EA. Furthermore, multiple holes 345 may be formed in the surface of the buffer layer 340, specifically in the area excluding the light-emitting area EA. It should be understood that "area excluding the light-emitting area EA" is not limited to excluding only the light-emitting area EA. Figure 12As shown, the luminescent area EA can extend between the sidewalls of the embankment 115f. In some embodiments, for example due to process variations, when the sidewall of the buffer layer 340 extends slightly beyond the sidewall of the embankment 115f, the area other than the luminescent area EA may slightly overlap with the luminescent area EA. In some embodiments, for example when the sidewall of the buffer layer 340 does not extend all the way to the sidewall of the embankment 115f, the area other than the luminescent area EA may not include an area slightly larger than the luminescent area EA.

[0233] To prevent non-luminescence due to damage to the light-emitting unit 132, which is susceptible to external impact, the buffer layer 340 can be formed only in the area excluding the light-emitting region EA, after which laser etching can be performed. In this case, non-luminescence can be prevented, thereby improving yield and display quality.

[0234] In particular, when the buffer layer 340 is formed only in the area other than the light-emitting area EA, the possibility that light that has not been reflected by the cathode 133 and has passed through the buffer layer 340 of the light-emitting area EA may be absorbed by the buffer layer 340 of the light-emitting area EA, thereby reducing the light efficiency, can be eliminated.

[0235] When multiple holes 345 are formed in the surface of the buffer layer 340 by laser etching, they may have a circular shape when viewed from above, but the invention is not limited thereto.

[0236] In order not to damage the cathode 133 and the light-emitting unit 132, the buffer layer 340 may be formed to have a thickness of at least 1 μm.

[0237] The buffer layer 340 may be formed, for example, from aluminum oxide.

[0238] The buffer layer 340 may be configured to extend into a portion of the non-active region NA to cover the cathode 133, but the invention is not limited thereto. The buffer layer 340 may be inclined along the inclined side surface of the cathode 133, but the invention is not limited thereto.

[0239] The hydrogen trap layer 350 can be disposed on the buffer layer 340 in which a plurality of holes 345 are formed.

[0240] The hydrogen trap layer 350 may be formed of an aluminum layer or may include aluminum.

[0241] The hydrogen trap layer 350 may be configured to extend into a portion of the non-active region NA to cover the buffer layer 340, but the invention is not limited thereto.

[0242] The hydrogen trap layer 350 may be tilted along the inclined side surface of the buffer layer 340, but the invention is not limited thereto.

[0243] When viewed in cross-section, a "V"-shaped groove 355 may correspond to a hole 345 formed in the surface of the hydrogen trap layer 350 below it, but the invention is not limited thereto.

[0244] In particular, a feature of the third exemplary embodiment of the present invention is that the hydrogen trapping layer 350 is deposited entirely on the buffer layer 340 deposited on the cathode 133, except for the light-emitting region EA. Thus, the hydrogen trapping layer 350 with a number of trap sites is formed by the buffer layer 340 in the non-light-emitting region through a plurality of holes 345. In the light-emitting region EA, a high-quality hydrogen trapping layer 350 with reflective properties is deposited on the cathode 133, thereby improving the light efficiency of the light-emitting region EA.

[0245] Furthermore, a feature of the third exemplary embodiment of the present invention is that a groove 355 having a “V” shape may correspond to a hole 345 formed below it in the surface of the hydrogen trapping layer 350, in addition to the light-emitting region EA.

[0246] Furthermore, this invention is not limited to bottom-emitting types; it can be applied to top-emitting types where light is emitted towards the upper part where a cathode is located, as described above. Figures 13 to 15 This will be described in detail.

[0247] Figure 13 This is a plan view of an electroluminescent display device according to a fourth exemplary embodiment of the present invention.

[0248] Figure 14 It is along Figure 13 A sectional view taken from line XIII-XIII'.

[0249] Figure 15 yes Figure 14 A magnified view of part A.

[0250] Figures 13 to 15 The fourth exemplary embodiment is the same as described above. Figures 3 to 5A The only difference from the first exemplary embodiment of 5B is that a top-emitting type is used, thus changing the formation positions of the buffer layer 440 and the hydrogen trap layer 450. The other structures are essentially the same, so repeated descriptions will be omitted. The same reference numerals are used for the same components.

[0251] Figure 14 The illustration shows a scenario where a touch unit or circuitry is included in the display panel 410, but the invention is not limited thereto.

[0252] Figure 15 yes Figure 14 An enlarged sectional view of part A.

[0253] Reference Figures 13 to 15 In the electroluminescent display device 400 according to the fourth exemplary embodiment of the present invention, a light-emitting element 430 including an anode 431, a light-emitting unit or structure 432 and a cathode 433 may be disposed on a planarization layer 115e.

[0254] The anode 431 can be disposed on the planarization layer 115e.

[0255] For example, in the case of a top-emitting type that emits light toward the upper part where the cathode 433 is provided, as in the fourth exemplary embodiment of the present invention, a reflective layer may be further included so that the emitted light is reflected from the anode 431 and emitted smoothly in the direction toward the upper part where the cathode 433 is provided.

[0256] In other words, the anode 431 can be a two-layer structure consisting of a transparent conductive layer and a reflective layer formed by sequentially stacking transparent conductive materials, or a three-layer structure consisting of sequentially stacked transparent conductive layers, reflective layers, and transparent conductive layers. The reflective layer can be formed of silver (Ag) or an alloy including silver.

[0257] The embankment 115f can be set on the anode 431 and the planarization layer 115e.

[0258] The light-emitting unit 432 can be disposed between the anode 431 and the cathode 433.

[0259] The cathode 433 is disposed on the light-emitting unit 432, and in the case of top light-emitting type, the cathode 433 can be a transparent conductive oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide (ZnO) and tin oxide (TO).

[0260] According to the fourth exemplary embodiment of the present invention, the buffer layer 440 may be disposed on the cathode 433.

[0261] The buffer layer 440 may be formed only in the area excluding the light-emitting area EA. Furthermore, multiple holes 445 may be formed in the surface of the buffer layer 440, specifically in the area excluding the light-emitting area EA. It should be understood that "the area excluding the light-emitting area EA" is not limited to excluding only the light-emitting area EA. Figure 15 As shown, the luminescent region EA may extend between the sidewalls of the embankment 115f. In some embodiments, for example due to process variations, when the sidewalls of the buffer layer 440 and / or the hydrogen trap layer 450 extend slightly beyond the sidewalls of the embankment 115f, the area other than the luminescent region EA may slightly overlap with the luminescent region EA. In some embodiments, for example when the sidewalls of the buffer layer 440 and / or the hydrogen trap layer 450 do not extend all the way to the sidewalls of the embankment 115f, the area other than the luminescent region EA may not include an area slightly larger than the luminescent region EA.

[0262] To prevent non-luminescence due to damage to the light-emitting unit 432, which is susceptible to external impact, the buffer layer 440 can be formed only in the area other than the light-emitting region EA, and laser etching can be performed. In this case, non-luminescence can be prevented, thereby improving yield and display quality.

[0263] In particular, when the buffer layer 440 is formed only in the region other than the light-emitting region EA, the possibility that light that is not reflected by the cathode 433 but passes through the buffer layer 440 of the light-emitting region EA will be absorbed by the buffer layer 440 of the light-emitting region EA, thereby reducing the light efficiency, can be eliminated.

[0264] When multiple holes 445 are formed in the surface of the buffer layer 440 by laser etching, they may have a circular shape when viewed from above, but the invention is not limited thereto.

[0265] In order not to damage the cathode 433 and the light-emitting unit 432, the buffer layer 440 may be formed to have a thickness of at least 1 μm.

[0266] The buffer layer 440 may be formed, for example, from aluminum oxide.

[0267] The buffer layer 440 may be configured to extend into a portion of the non-active region NA to cover the cathode 433, but the invention is not limited thereto. The buffer layer 440 may be inclined along the inclined side surface of the cathode 433, but the invention is not limited thereto.

[0268] A hydrogen trap layer 450 may be disposed on a buffer layer 440 in which a plurality of holes 445 are formed.

[0269] The hydrogen trap layer 450 can be formed from an aluminum layer.

[0270] A feature of the fourth exemplary embodiment of the present invention is that the hydrogen trapping layer 450 is formed only in the region other than the light-emitting region EA. That is, the hydrogen trapping layer 450 may be formed only on the buffer layer 440 other than the light-emitting region EA.

[0271] Since the hydrogen trapping layer 450 is formed of an aluminum layer, it is opaque. Therefore, it is preferable to use a bottom-emitting type when the hydrogen trapping layer 450 is deposited on the entire surface of the display panel 410. In the case of a top-emitting type where light emitted upward from the organic layer that serves as the light-emitting unit 432 is used, as in the fourth exemplary embodiment of the present invention, it is preferable to form the opaque hydrogen trapping layer 450 only in the area other than the light-emitting area EA.

[0272] The hydrogen trap layer 450 may be configured to extend into a portion of the non-active region NA to cover the buffer layer 440, but the invention is not limited thereto.

[0273] The hydrogen trap layer 450 may be tilted along the inclined side surface of the buffer layer 440, but the invention is not limited thereto.

[0274] When viewed in cross-section, a "V"-shaped groove 455 may correspond to a hole 445 formed in the surface of the hydrogen trap layer 450 below it, but the invention is not limited thereto.

[0275] Exemplary embodiments of the present invention can also be described as follows:

[0276] According to one aspect of the present invention, an electroluminescent display device is provided. The electroluminescent display device includes: a substrate, the substrate including an active region having a light-emitting region and an active region; a planarization layer disposed on the substrate; a light-emitting element disposed on the planarization layer; a buffer layer disposed on the light-emitting element and having a plurality of holes in its surface; and a hydrogen trapping layer disposed on the buffer layer.

[0277] The light-emitting element may include: an anode; a light-emitting unit disposed on the anode; and a cathode disposed on the light-emitting unit.

[0278] The electroluminescent display device may further include a thin-film transistor disposed on the substrate and electrically connected to the anode, wherein the thin-film transistor includes a semiconductor layer made of oxide semiconductor.

[0279] The plurality of holes may have a checkerboard shape on a plane, and each hole may have a circular shape.

[0280] The buffer layer may be made of aluminum oxide, and the hydrogen trapping layer may be made of aluminum.

[0281] The buffer layer may be configured to extend into a portion of the non-active region to cover the cathode.

[0282] The buffer layer may have an inclined portion along the inclined side surface of the cathode.

[0283] The plurality of holes may be disposed on the surface of the buffer layer, excluding the light-emitting area.

[0284] The buffer layer can be disposed in an area other than the light-emitting area.

[0285] The hydrogen trap layer can be disposed in a region other than the luminescent region.

[0286] The electroluminescent display device can be configured as a top-emitting type.

[0287] The hydrogen trap layer may have misaligned or point-defect hydrogen trap locations in the direction perpendicular to the pore.

[0288] The hydrogen trap layer may be configured to extend into a portion of the non-active region to cover the buffer layer.

[0289] The hydrogen trap layer may have an inclination along the inclined side surface of the buffer layer.

[0290] The hydrogen trap layer has grooves on its surface corresponding to the holes, and the grooves have a "V" shaped profile.

[0291] According to another aspect of the present invention, an electroluminescent display device is provided, comprising: a planarization layer disposed on a substrate; a light-emitting element disposed on the planarization layer; a buffer layer disposed on the light-emitting element and having a plurality of holes therein; and a hydrogen trapping layer disposed on the buffer layer and having grooves therein corresponding to the holes.

[0292] The buffer layer may be made of aluminum oxide, and the hydrogen trap layer may be made of aluminum.

[0293] The plurality of holes may be disposed on the surface of the buffer layer, excluding the light-emitting area.

[0294] The buffer layer can be disposed in an area other than the light-emitting area.

[0295] The hydrogen trap layer can be disposed in a region other than the luminescent region.

[0296] Although exemplary embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited thereto, and can be implemented in many different forms without departing from the technical concept of the present invention. Therefore, the exemplary embodiments of the present invention are provided for illustrative purposes only and are not intended to limit the technical concept of the present invention. The scope of the technical concept of the present invention is not limited thereto. Therefore, it should be understood that the above exemplary embodiments are merely illustrative in all respects and do not limit the present invention. The scope of protection of the present invention should be interpreted based on the appended claims, and all technical concepts within the equivalent scope should be interpreted as falling within the scope of the present invention.

Claims

1. An electroluminescent display device, comprising: A substrate, the substrate including an active region and a non-active region, the active region having a light-emitting region; A planarization layer disposed on the substrate; Light-emitting elements disposed on the planarization layer; A buffer layer is disposed on the light-emitting element and has a plurality of holes in its surface; as well as A hydrogen trap layer is disposed on the buffer layer. The plurality of pores in the surface of the buffer layer are configured to serve as seeds to generate and grow defects in the hydrogen trap layer.

2. The electroluminescent display device according to claim 1, wherein the light-emitting element comprises: anode; A light-emitting unit disposed on the anode; as well as The cathode is disposed on the light-emitting unit.

3. The electroluminescent display device according to claim 2 further includes a thin-film transistor disposed on the substrate and electrically connected to the anode. The thin-film transistor includes a semiconductor layer having an oxide semiconductor.

4. The electroluminescent display device according to claim 1, wherein the plurality of holes have a checkerboard shape on a plane, and each hole has a circular shape.

5. The electroluminescent display device according to claim 1, wherein the buffer layer comprises aluminum oxide and the hydrogen trapping layer comprises aluminum.

6. The electroluminescent display device of claim 2, wherein the buffer layer is configured to extend into a portion of the non-active region to cover the cathode.

7. The electroluminescent display device according to claim 6, wherein the buffer layer has an inclined portion along the inclined side surface of the cathode.

8. The electroluminescent display device according to claim 1, wherein the plurality of holes are disposed in the surface of the buffer layer in a region other than the light-emitting area.

9. The electroluminescent display device according to claim 8, wherein the buffer layer is disposed in a region other than the light-emitting region.

10. The electroluminescent display device according to claim 9, wherein the hydrogen trapping layer is disposed in a region other than the light-emitting region.

11. The electroluminescent display device according to claim 1, wherein the hydrogen trap layer has hydrogen trap positions as misalignments or point defects in a direction perpendicular to the aperture.

12. The electroluminescent display device of claim 7, wherein the hydrogen trapping layer is configured to extend into a portion of the non-active region to cover the buffer layer.

13. The electroluminescent display device of claim 12, wherein the hydrogen trapping layer has an inclination along the inclined side surface of the buffer layer.

14. The electroluminescent display device according to claim 1, wherein the hydrogen trap layer has a groove in its surface corresponding to the hole, the groove having a "V" shaped profile.

15. An electroluminescent display device, comprising: A planarization layer disposed on a substrate; Light-emitting elements disposed on the planarization layer; A buffer layer is disposed on the light-emitting element and has a plurality of holes in its surface; as well as A hydrogen trapping layer is disposed on the buffer layer and has grooves on its surface corresponding to the holes. The plurality of pores in the surface of the buffer layer are configured to serve as seeds to generate and grow defects in the hydrogen trap layer.

16. The electroluminescent display device of claim 15, wherein the buffer layer comprises aluminum oxide and the hydrogen trapping layer comprises aluminum.

17. The electroluminescent display device according to claim 15, wherein the plurality of holes are disposed in the surface of the buffer layer other than the light-emitting area.

18. The electroluminescent display device according to claim 17, wherein the buffer layer is disposed in a region other than the light-emitting region.

19. The electroluminescent display device according to claim 18, wherein the hydrogen trapping layer is disposed in a region other than the light-emitting region.

20. A method comprising: A planarization layer is formed on the substrate; A light-emitting element is formed on the planarization layer; A buffer layer is formed on the light-emitting element; Multiple holes are formed in the buffer layer; as well as A hydrogen trap layer is formed on the buffer layer, the hydrogen trap layer having a plurality of grooves on its surface, each of the plurality of grooves overlapping a corresponding one of the plurality of holes. The plurality of pores in the surface of the buffer layer are configured to serve as seeds to generate and grow defects in the hydrogen trap layer.

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