DISPLAY DEVICE

Abstract

Embodiments of the present disclosure relate to a display device. By including a first electrode layer arranged on a passivation layer having at least one hole in an emission region and located in a region other than that containing the at least one hole, or by including a first electrode layer comprising an upper electrode layer and a lower electrode layer located beneath the upper electrode layer, it is possible to create a display device that can improve light extraction efficiency.

Description

[0001] This application claims priority to Korean Patent Application No. 10-2023-0157500, filed on November 14, 2023. Background area

[0002] Embodiments of the present disclosure relate to a display device. Description of the state of the art

[0003] An organic light-emitting display device is a self-luminous display device and, unlike a liquid crystal display, can be manufactured in a lighter and thinner form because no separate light source is required.

[0004] The organic light-emitting display device not only offers advantages in terms of power consumption due to low-power driving, but also has excellent color reproduction, response speed, viewing angle, and contrast ratio. Therefore, the organic light-emitting display device is being researched as a next-generation display device.

[0005] Light emitted from the light-emitting layer of the organic light-emitting display device passes through various components of the organic light-emitting display device and exits the organic light-emitting display device.

[0006] However, in the light emitted from the light-emitting layer, there is included light that does not exit the organic light-emitting display device and is trapped inside the organic light-emitting display device, which causes a problem in the light extraction efficiency of the organic light-emitting display device.

[0007] In order to improve the light extraction efficiency of such an organic light-emitting display device, a method of forming a microlens array (MLA) in the overcoat layer of the organic light-emitting display device has been proposed.

[0008] However, despite forming the microlens array (MLA) in the overcoat layer of the organic light-emitting display device, there is a problem that much light is trapped inside the organic light-emitting display device and therefore the amount of light extracted to the outside is not large.

[0009] Therefore, there is a need for an organic light-emitting display device that can improve the luminous efficiency and light extraction efficiency. Short summary

[0010] Therefore, there is a need to provide a display device that can improve the light extraction efficiency.

[0011] There is also a need to provide a display device that can return light that is to be extinguished internally to the low-power driver.

[0012] Each of the above-mentioned problems, or a problem that will become apparent to those skilled in the art from the present description, is solved by the features of the independent claims. Further aspects of the display device are specified in the respective dependent claims.

[0013] According to one aspect of the present disclosure, a display device comprises: a substrate having an emitting region and a non-emissive region; a cladding layer disposed on the substrate; a passivation layer disposed on the cladding layer and having at least one hole in the emitting region; a first electrode layer disposed on an upper surface of the passivation layer and located in a region different from the at least one hole; a light-emitting layer disposed on the first electrode layer and covering the cladding layer and the passivation layer in the at least one hole; and a second electrode layer disposed on the light-emitting layer.

[0014] According to another aspect of the present disclosure, a display device comprises: a substrate having an emitting region and a non-emissive region; a cladding layer disposed on the substrate; a first electrode layer disposed on the cladding layer, having at least one hole in the emitting region, and comprising an upper electrode layer and a lower electrode layer disposed below the upper electrode layer; a light-emitting layer disposed on the first electrode layer and covering the cladding layer and the first electrode layer in the at least one hole; and a second electrode layer disposed on the light-emitting layer.

[0015] According to another aspect of the present disclosure, a display device comprises: a substrate; a coating layer disposed on the substrate; a passivation layer disposed on the coating layer and having at least one hole exposing a partial upper surface of the coating layer; a first electrode layer disposed on an upper surface of the passivation layer and exposing the at least one hole; a light-emitting layer disposed on the first electrode layer and in the at least one hole; and a second electrode layer disposed on the light-emitting layer.

[0016] The display devices according to the above aspects may further comprise one or more of the following features:

[0017] The thickness of the passivation layer can be greater than the thickness of the first electrode layer. The "thickness" dimension can be understood as the dimension perpendicular to the substrate.

[0018] The display device may further include an interconnection pattern disposed on the substrate. The display device may further include a contact portion extending through the passivation layer and the overlay layer. In the contact portion, the first electrode layer and the interconnection pattern may be electrically connected to each other. The display device may further include a bank layer disposed on the first electrode layer. The bank layer may fill the contact portion.

[0019] The light-emitting layer and / or the second electrode layer can be arranged in the contact section according to the shape of the contact section. Alternatively or additionally, the light-emitting layer and / or the second electrode layer can be arranged according to the shape of the first electrode layer. In particular, the light-emitting layer and / or the second electrode layer can be arranged in the contact section according to the shape of the first electrode layer.

[0020] The coating layer may be formed from at least two layers. The coating layer may comprise at least two layers.

[0021] The overcoat layer may have at least one concave portion. The concave portion may be formed of a flat portion and an inclined portion surrounding the flat portion. The concave portion may have an inclined portion defining a periphery of the concave portion. The concave portion may surround the first electrode layer in the contact portion. The overcoat layer may have a groove at least partially surrounding the first electrode. The groove may define the at least one concave portion. The groove may have an inclined sidewall. The groove may have a substantially V-shaped profile. The passivation layer or the lower electrode layer may cover the inclined portion or the inclined sidewall. The passivation layer or the lower electrode layer may overlap at least a portion of the flat portion.

[0022] The thickness of the lower electrode layer may be smaller than the thickness of the upper electrode layer.

[0023] The etching rate of the lower electrode layer can be higher than the etching rate of the upper electrode layer.

[0024] The upper electrode layer may be made of indium tin oxide (ITO). The lower electrode layer may be made of at least one transparent conductive oxide having an etching rate higher than that of ITO. The lower electrode layer may be made of a translucent metal.

[0025] The display device may further comprise an interconnection pattern arranged on the substrate. The display device may further comprise a contact portion extending through the overlay layer. In the contact portion, the first electrode layer and the interconnection pattern may be electrically connected to each other. In the contact portion, the lower electrode layer and the interconnection pattern may be electrically connected to each other. The display device may further comprise a bank layer arranged on the first electrode layer, in particular on the upper electrode layer. The bank layer may fill the contact portion.

[0026] According to aspects of the present disclosure, it is possible to provide a display device that can improve light extraction efficiency.

[0027] According to aspects of the present disclosure, it is possible to provide a display device capable of returning light to be extinguished internally for low-power driving. Brief description of the drawings Fig. 1 is a diagram showing the schematic system configuration of a display device according to aspects of the present disclosure. Fig. 2 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to an aspect of the present disclosure. Fig. 3 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another aspect of the present disclosure. Fig. 4 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another aspect of the present disclosure. Fig. 5 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another aspect of the present disclosure. Fig. 6 is an enlarged view of area A of Fig. 5. Fig. 7 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another aspect of the present disclosure. Fig. 8 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another aspect of the present disclosure. Detailed description

[0028] In the following description of examples or embodiments of the disclosure, reference is made to the accompanying drawings, in which, for illustrative purposes, specific examples or embodiments that may be implemented are shown, and in which the same reference numbers and characters may be used to refer to the same or similar components even though they are shown in different accompanying drawings. Furthermore, in the following description of examples or embodiments of the disclosure, detailed descriptions of well-known functions and components included herein are omitted when it is determined that the description may tend to obscure the subject matter in some embodiments of the disclosure.As used herein, terms such as "comprise," "comprise," "contain," "consist of," and "constructed of" are generally intended to allow for the addition of other components unless the terms are used with the term "only." As used herein, singular forms are intended to include plural forms unless the context clearly indicates otherwise.

[0029] Terms such as "first," "second," "A," "B," "(A)," or "(B)" may be used herein to describe elements of the disclosure. Each of these terms is not used to define the nature, order, sequence, or number of elements, etc., but merely serves to distinguish the corresponding element from other elements.

[0030] When it is mentioned that a first element is "connected or coupled", "contacts or overlaps", etc., with a second element, this should be interpreted to mean that the first element may not only be "directly connected or coupled" or "directly contact or overlap" the second element, but also that a third element may be "interposed" between the first and second elements, or that the first and second elements may be "connected or coupled", "contact or overlap", etc., via a fourth element. The second element may be included in at least one of two or more elements that are "connected or coupled", "contact or overlap", etc.

[0031] When time-relationship terms such as "after," "subsequent," "next," "before," and the like are used to describe processes or operations of elements or configurations or sequences or steps in methods of operation, processing, or manufacturing, these terms may be used to describe non-consecutive or non-sequential processes or operations unless the term "direct" or "immediate" is used together with them.

[0032] Furthermore, when mentioning dimensions, relative sizes, etc., it should be considered that numerical values ​​for elements or characteristics, or corresponding information (e.g., level, range, etc.), include a range of tolerance or error that may be caused by various factors (e.g., process factors, internal or external shocks, noise, etc.), even if no relevant description is provided. Furthermore, the term "may" includes all meanings of the term "can."

[0033] In the following, various embodiments are described in detail with reference to the accompanying drawings.

[0034] Fig. 1 is a diagram showing the schematic system configuration of a display device according to embodiments of the present disclosure.

[0035] With reference to Fig. 1, the driving system of the display device 100 according to embodiments of the present disclosure may include a display panel 110 and a display driving circuit for driving the display panel 110.

[0036] The display panel 110 may include a display area DA in which an image is displayed and a non-display area NDA in which no image is displayed.

[0037] The display panel 110 may include a plurality of sub-pixels SP arranged on a substrate 200 to display an image.

[0038] The substrate 200 may have an emitting region and a non-emitting region.

[0039] The display panel 110 may include a plurality of signal wirings arranged on the substrate 200.

[0040] For example, the plurality of signal wirings may include data lines DL, gate lines GL, drive voltage lines, etc.

[0041] Each of the plurality of data lines DL may be arranged to run in a first direction (in one example, a column direction or in another example, a row direction), and each of the plurality of gate lines GL may be arranged to run in a second direction (in one example, a row direction or in another example, a column direction) that is orthogonal to the first direction.

[0042] The display drive circuit may include a data drive circuit 120, a gate drive circuit 130, and a controller 140.

[0043] The controller 140 can control the data drive circuit 120 and the gate drive circuit 130.

[0044] The data drive circuit 120 can output data signals corresponding to an image signal to the plurality of data lines DL.

[0045] The gate drive circuit 130 can generate gate signals and output the gate signals to the plurality of gate lines GL.

[0046] The controller 140 may convert image data input from an external host 150 to match a data signal format used in the data drive circuit 120, and may supply the converted image data Data to the data drive circuit 120. The controller 140 may also supply a data control signal DCS to the data drive circuit 120 and a gate control signal GCS to the gate drive circuit 130.

[0047] The data drive circuit 120 may include at least one integrated source drive circuit.

[0048] For example, each source drive integrated circuit may be connected to the display panel 110 in a tape-automated bonding (TAB) process, connected to the bond pads of the display panel 110 in a chip-on-glass (COG) or chip-on-panel (COP) process, or connected to the display panel 110 by implementation in a chip-on-film (COF) process.

[0049] The gate drive circuit 130 may be connected to the display panel 110 in a tape-automated bonding (TAB) method, connected to the bonding pads of the display panel 110 in a COG method or COP method, or formed in the non-display area NDA of the display panel 110 in a gate-in-panel (GIP) type.

[0050] With reference to Fig. 1, in the display device 100 according to the embodiments of the present disclosure, each sub-pixel SP may include a light-emitting element ED and a pixel driving circuit SPC for driving the light-emitting element ED.

[0051] The pixel drive circuit SPC may include a drive transistor DRT, a scan transistor SCT and a storage capacitor Cst.

[0052] The drive transistor DRT can drive the light-emitting element ED by controlling the current flowing to the light-emitting element ED.

[0053] The sampling transistor SCT can transmit a data voltage Vdata to a second node N2, which is the gate node of the driving transistor DRT.

[0054] The storage capacitor Cst may be designed to maintain a voltage for a predetermined period of time.

[0055] The light-emitting element ED may include a first electrode layer 250, a second electrode layer 280 and a light-emitting layer 270.

[0056] The light-emitting layer 270 is located between the first electrode layer 250 and the second electrode layer 280.

[0057] The first electrode layer 250 may be a pixel electrode involved in the formation of the light-emitting element ED of each sub-pixel SP and may be electrically connected to a first node N1 of the drive transistor DRT.

[0058] The second electrode layer 280 may be a common electrode involved in the formation of the light-emitting elements ED of all sub-pixels SP, and a ground voltage EVSS may be applied thereto.

[0059] For example, the light-emitting element ED can be an organic light-emitting diode (OLED), an inorganic light-emitting diode (LED) or a light-emitting quantum dot (QD) element.

[0060] When the display device 100 according to the embodiments of the present disclosure is an OLED display, each sub-pixel SP may include an organic light-emitting diode (OLED) as a light-emitting element.

[0061] When the display device 100 according to embodiments of the present disclosure is a quantum dot (QD) light-emitting element, each sub-pixel SP may include a quantum dot (QD) light-emitting element.

[0062] When the display device 100 according to the embodiments of the present disclosure is a micro-LED display, each sub-pixel SP may include, as a light-emitting element, a micro-light emitting diode (micro-LED) that emits light itself and is made of an inorganic material.

[0063] The drive transistor DRT as a transistor for driving the light-emitting element ED may include the first node N1, the second node N2 and a third node N3.

[0064] The first node N1 may be a source or drain node and may be electrically connected to the first electrode layer 250 of the light-emitting element ED.

[0065] The second node N2 may be the gate node and may be electrically connected to a source or drain node of the sampling transistor SCT.

[0066] The third node N3 may be a drain or source node and may be electrically connected to a drive voltage line DVL that supplies a drive voltage EVDD.

[0067] In this document, it is described as an example that the first node N1 is a source node and the third node N3 is a drain node.

[0068] The sampling transistor SCT can switch the connection between a data line DL and the second node N2 of the driving transistor DRT.

[0069] In response to a scanning signal SCAN supplied from a scanning line SCL as a kind of gate line GL, the scanning transistor SCT can control the connection between the second node N2 of the driving transistor DRT and a corresponding data line DL among the plurality of data lines DL.

[0070] The storage capacitor Cst may be formed between the first node N1 and the second node N2 of the drive transistor DRT.

[0071] The Fig. The structure of the subpixel SP shown in Figure 1 is merely an example for explanation purposes and may further comprise at least one transistor or at least one capacitor.

[0072] Respective ones of the plurality of sub-pixels SP may have the same structure and some of the plurality of sub-pixels SP may have a different structure.

[0073] The drive transistor DRT and the sense transistor SCT can each be an n-type transistor or a p-type transistor.

[0074] The display device 100 according to embodiments of the present disclosure may have a top emission structure or a bottom emission structure.

[0075] In the following, the lower emission structure is described as an example in this document.

[0076] For example, in the case of the bottom emission structure, the first electrode layer 250 may be a conductive material that is transparent or semitransparent to light, and the second electrode layer 280 may be reflective metal.

[0077] Fig. 2 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to an embodiment of the present disclosure.

[0078] With reference to Fig. 2, a connection pattern 210 electrically connected to a transistor may be arranged on a substrate 200.

[0079] For example, the connection pattern 210 may electrically connect the drive transistor DRT and the light-emitting element ED, but is not limited thereto.

[0080] A buffer layer 220 may be disposed on the substrate 200, covering the interconnection pattern 210.

[0081] A color filter layer 230 may be arranged on the buffer layer 220.

[0082] In addition, an overcoat layer 240 may be disposed on the buffer layer 220, covering the color filter layer 230.

[0083] The coating layer 240 may be a single layer or a multi-layer, but in Fig. 2, the display device in which the coating layer 240 consists of two layers is described as an example.

[0084] When the overcoat layer 240 consists of two layers, the overcoat layer 240 may include a first overcoat layer 241 disposed on the buffer layer 220 and covering the color filter layer 230, and a second overcoat layer 242 disposed on the first overcoat layer 241.

[0085] The first coating layer 241 and the second coating layer 242 may be made of different materials to improve the light extraction efficiency.

[0086] For example, the first cladding layer 241 and the second cladding layer 242 may be designed to have different refractive indices to improve the light extraction efficiency.

[0087] However, the embodiment of the present disclosure is not limited thereto, and the first coating layer 241 and the second coating layer 242 may be made of substantially the same material.

[0088] In the present disclosure, taking into account minute differences due to an error in a process, substantially equal may mean the same degree.

[0089] With reference to Fig. 2, the display device according to the first embodiment of the present disclosure may include a passivation layer 300 disposed on the cladding layer 240 and having at least one hole H in an emission region, a first electrode layer 250 disposed on the upper surface of the passivation layer 300 and located in a region other than the at least one hole H, a light-emitting layer 270 disposed on the first electrode layer 250 and covering the cladding layer 240 and the passivation layer 300 in the hole H, and a second electrode layer 280 disposed on the light-emitting layer 270.

[0090] The first electrode layer 250 may include a conductive material that is transparent or semitransparent to light.

[0091] For example, the first electrode layer 250 may contain at least one type of transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide, and tin oxide, or may contain translucent metal such as magnesium, silver, and a magnesium-silver alloy.

[0092] The light-emitting layer 270 of the light-emitting element ED may be formed by a deposition or coating method having a directional effect.

[0093] For example, the light-emitting layer 270 may be formed by physical vapor deposition (PVD).

[0094] The light-emitting layer 270 may include a red organic light-emitting layer disposed in a red sub-pixel (R), a green organic light-emitting layer disposed in a green sub-pixel (G), and a blue organic light-emitting layer disposed in a blue sub-pixel (B).

[0095] The second electrode layer 280 may contain reflective metal.

[0096] Fig. 2 shows a configuration in which the second electrode layer 280 is a single layer. However, the embodiment of the present disclosure is not limited thereto, and the second electrode layer 280 may be composed of a multilayer.

[0097] For example, if the second electrode layer 280 consists of a multilayer, at least one layer may contain reflective metal.

[0098] The second electrode layer 280 may include, for example, aluminum, neodymium, nickel, titanium, tantalum, copper, silver, and / or an aluminum alloy, but the embodiment of the present disclosure is not limited thereto.

[0099] In the display device according to the first embodiment of the present disclosure, since the first electrode layer 250 is located on the upper surface of the passivation layer 300 and is located in the region other than the at least one hole H, it is possible to prevent a reduction in the thickness of the second electrode layer 280.

[0100] The passivation layer 300 may use, but is not limited to, an oxide or nitride-based material.

[0101] When the thickness of the passivation layer 300 is greater than the thickness of the first electrode layer 250, it is possible to prevent a reduction in the thickness of the second electrode layer 280 and improve the light extraction efficiency.

[0102] The thickness of the passivation layer 300 can be 100 nm to 1000 nm.

[0103] In this way, by adjusting the thickness of the passivation layer 300, the depth of the hole H can be adjusted.

[0104] The first embodiment of the present disclosure may further include a contact portion CNT passing through the passivation layer 300 and the overlay layer 240.

[0105] In the contact portion CNT, the first electrode layer 250 and the connection pattern 210 arranged on the substrate 200 may be electrically connected.

[0106] A bank layer 260 disposed on the first electrode layer 250 and filling the contact portion CNT may be further included.

[0107] Fig. 3 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another embodiment of the present disclosure.

[0108] Details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the bank layer 260, the light-emitting layer 270, the second electrode layer 280, the passivation layer 300, the hole H and the contact portion CNT of Fig. 3 may be substantially the same as the details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the bank layer 260, the light-emitting layer 270, the second electrode layer 280, the passivation layer 300, the hole H, and the contact portion CNT described above with reference to Fig. 2 are described.

[0109] With reference to Fig. 3, the coating layer 240 of the display device according to the second embodiment of the present disclosure may include at least one concave part 400 consisting of a flat portion FLT and an inclined portion SLO surrounding the flat portion FLT.

[0110] The passivation layer 300 may cover the inclined portion SLO and overlap at least a portion of the flat portion FLT.

[0111] A region where the passivation layer 300 does not overlap the flat portion FLT may overlap the light-emitting layer 270.

[0112] Since the overcoat layer 240 includes the concave part 400, when forming the passivation layer 300 and the light-emitting layer 270, the passivation layer 300 and the light-emitting layer 270 can be formed according to the shape of the concave part 400.

[0113] Since the overcoat layer 240 includes the concave part 400 and the passivation layer 300 has the hole H, when forming the second electrode layer 280, the second electrode layer 280 can be formed according to the shapes of the concave part 400 and the hole H. Therefore, it is possible to prevent a reduction in the thickness of the second electrode layer 280 and improve the light extraction efficiency.

[0114] Fig. 4 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another embodiment of the present disclosure.

[0115] Details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the light-emitting layer 270, the second electrode layer 280, the passivation layer 300, the hole H and the contact portion CNT of Fig. 4 may be substantially the same as the details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the light-emitting layer 270, the second electrode layer 280, the passivation layer 300, the hole H, and the contact portion CNT described above with reference to Fig. 2 are described.

[0116] With reference to Fig. 4, in the display device according to the third embodiment of the present disclosure, the light-emitting layer 270 and the second electrode layer 280 may be arranged in the contact portion CNT according to the shape of the contact portion CNT.

[0117] Accordingly, it is possible to perform the function of the light-emitting element ED even in the contact portion CNT.

[0118] Since the second electrode layer 280 is formed according to the shape of the contact portion CNT, light to be extinguished internally can be returned and extracted to the outside.

[0119] In other words, the second electrode layer 280 can perform the function of a microlens array (MLA).

[0120] However, the embodiment of the present disclosure is not limited thereto, and a microlens array (MLA) may be formed on the cladding layer 240 to improve the light extraction efficiency.

[0121] The microlens array (MLA) formed on the overcoat layer 240 may contain reflective metal, like the second electrode layer 280.

[0122] In order to increase the area of ​​the second electrode layer 280 and thereby improve the light extraction efficiency, it is preferable that the coating layer 240 be formed to consist of at least two layers.

[0123] Fig. 5 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another embodiment of the present disclosure.

[0124] With reference to Fig. 5, a connection pattern 210 electrically connected to a transistor may be arranged on a substrate 200.

[0125] For example, the connection pattern 210 may electrically connect the drive transistor DRT and the light-emitting element ED, but is not limited thereto.

[0126] A buffer layer 220 may be disposed on the substrate 200, covering the interconnection pattern 210.

[0127] A color filter layer 230 may be arranged on the buffer layer 220.

[0128] In addition, an overcoat layer 240 may be disposed on the buffer layer 220, covering the color filter layer 230.

[0129] The coating layer 240 may be a single layer or a multi-layer, but in Fig. 5, the display device in which the coating layer 240 consists of two layers is described as an example.

[0130] When the overcoat layer 240 consists of two layers, the overcoat layer 240 may include a first overcoat layer 241 disposed on the buffer layer 220 and covering the color filter layer 230, and a second overcoat layer 242 disposed on the first overcoat layer 241.

[0131] The first coating layer 241 and the second coating layer 242 may be made of different materials to improve the light extraction efficiency.

[0132] For example, the first cladding layer 241 and the second cladding layer 242 may be designed to have different refractive indices to improve the light extraction efficiency.

[0133] However, the embodiment of the present disclosure is not limited thereto, and the first coating layer 241 and the second coating layer 242 may be made of substantially the same material.

[0134] With reference to Fig. 5, the display device according to the fourth embodiment of the present disclosure may include a first electrode layer 250 disposed on the cladding layer 240 and having at least one hole H in an emission region, a light-emitting layer 270 disposed on the first electrode layer 250 and covering the cladding layer 240 and the first electrode layer 250 in the hole H, and a second electrode layer 280 disposed on the light-emitting layer 270.

[0135] The first electrode layer 250 may comprise a conductive material that is transparent or semitransparent to light.

[0136] For example, the first electrode layer 250 may contain at least one type of transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide, and tin oxide, or may contain translucent metal such as magnesium, silver, and a magnesium-silver alloy.

[0137] The first electrode layer 250 may include an upper electrode layer 251 and a lower electrode layer 252 located below the upper electrode layer 251.

[0138] The thickness of the lower electrode layer 252 may be smaller than the thickness of the upper electrode layer 251.

[0139] When the thickness of the lower electrode layer 252 is smaller than the thickness of the upper electrode layer 251, when forming the second electrode layer 280 according to the shape of the hole H, the thickness of the second electrode layer 280 can be prevented from being reduced.

[0140] The lower electrode layer 252 can be formed using a material whose etching rate is greater than the etching rate of the upper electrode layer 251.

[0141] For example, the upper electrode layer 251 can be made of ITO and the lower electrode layer 252 can be made of at least one material selected from transparent conductive oxide or transparent metal with an etching rate higher than that of ITO.

[0142] The lower electrode layer 252 is preferably made of IZO.

[0143] Since the lower electrode layer 252 is formed using a material whose etching rate is greater than the etching rate of the upper electrode layer 251, in an etching step, the lower electrode layer 252 can be etched more strongly than the upper electrode layer 251 to form an undercut UC.

[0144] By forming the undercut UC, it is possible to prevent a reduction in the thickness of the second electrode layer 280 when forming the second electrode layer 280.

[0145] The light-emitting layer 270 of the light-emitting element ED may be formed by a deposition or coating method having a directional effect.

[0146] For example, the light-emitting layer 270 may be formed by physical vapor deposition (PVD).

[0147] The light-emitting layer 270 may include a red organic light-emitting layer disposed in a red sub-pixel (R), a green organic light-emitting layer disposed in a green sub-pixel (G), and a blue organic light-emitting layer disposed in a blue sub-pixel (B).

[0148] The second electrode layer 280 may contain reflective metal.

[0149] Fig. 5 shows a configuration in which the second electrode layer 280 is a single layer. However, the embodiment of the present disclosure is not limited to this, and the second electrode layer 280 may be composed of a multilayer.

[0150] For example, if the second electrode layer 280 is comprised of a multilayer, at least one layer may contain reflective metal.

[0151] The second electrode layer 280 may include, for example, aluminum, neodymium, nickel, titanium, tantalum, copper, silver, and / or an aluminum alloy, but the embodiment of the present disclosure is not limited thereto.

[0152] Fig. 6 is an enlarged view of area A of Fig. 5.

[0153] With reference to Fig. 6, as described above, the lower electrode layer 252 may be arranged below the upper electrode layer 251.

[0154] In addition, as described above, since the lower electrode layer 252 is formed using a material whose etching rate is greater than the etching rate of the upper electrode layer 251, in one etching step, the lower electrode layer 252 can be etched more than the upper electrode layer 251 to form the undercut UC.

[0155] With reference to Fig. 6, when the second electrode layer 280 is formed according to the shape of the hole H, a recess is formed by a taper angle α around the hole H, and a step D is formed.

[0156] The height of the undercut UC can be adjusted by adjusting the thickness of the lower electrode layer 252, and the taper angle a and the height of the step D can be adjusted by adjusting the height of the undercut UC.

[0157] The preferred thickness of the lower electrode layer 252 is 100 nm to 500 nm.

[0158] The fourth embodiment of the present disclosure may further include a contact portion CNT passing through the overlay layer 240.

[0159] In the contact portion CNT, the first electrode layer 250 and the connection pattern 210 arranged on the substrate 200 may be electrically connected.

[0160] A bank layer 260 disposed on the first electrode layer 250 and filling the contact portion CNT may additionally be included.

[0161] Fig. 7 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another embodiment of the present disclosure.

[0162] Details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the upper electrode layer 251, the lower electrode layer 252, the bank layer 260, the light-emitting layer 270, the second electrode layer 280, the hole H and the contact portion CNT of Fig. 7 may be substantially the same as the details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the upper electrode layer 251, the lower electrode layer 252, the bank layer 260, the light-emitting layer 270, the second electrode layer 280, the hole H, and the contact portion CNT described above with reference to Fig. 5 are described.

[0163] With reference to Fig. 7, the coating layer 240 of the display device according to the fifth embodiment of the present disclosure may include at least one concave part 400 consisting of a flat portion FLT and an inclined portion SLO surrounding the flat portion FLT.

[0164] The lower electrode layer 252 may cover the inclined portion SLO and overlap at least a portion of the flat portion FLT.

[0165] A region where the lower electrode layer 252 does not overlap the flat portion FLT may overlap the light-emitting layer 270.

[0166] Since the coating layer 240 includes the concave part 400, when forming the light-emitting layer 270, the light-emitting layer 270 can be formed according to the shape of the concave part 400.

[0167] Since the overcoat layer 240 includes the concave part 400 and the first electrode layer 250 has the hole H, when forming the second electrode layer 280, the second electrode layer 280 can be formed according to the shapes of the concave part 400 and the hole H. Therefore, it is possible to prevent a reduction in the thickness of the second electrode layer 280 and improve the light extraction efficiency.

[0168] Fig. 8 is a cross-sectional view of an example of a pixel structure arranged in the display panel of a display device according to another embodiment of the present disclosure.

[0169] Details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the upper electrode layer 251, the lower electrode layer 252, the light-emitting layer 270, the second electrode layer 280, the hole H and the contact portion CNT of Fig. 8 may be substantially the same as the details regarding the substrate 200, the connection pattern 210, the buffer layer 220, the color filter layer 230, the overcoat layer 240, the first electrode layer 250, the upper electrode layer 251, the lower electrode layer 252, the light-emitting layer 270, the second electrode layer 280, the hole H, and the contact portion CNT described above with reference to Fig. 5 are described.

[0170] With reference to Fig. 8, in the display device according to the sixth embodiment of the present disclosure, the light-emitting layer 270 and the second electrode layer 280 may be arranged in the contact portion CNT according to the shape of the contact portion CNT.

[0171] Accordingly, it is possible to perform the function of the light-emitting element ED even in the contact portion CNT.

[0172] Since the second electrode layer 280 is formed according to the shape of the contact portion CNT, light to be extinguished internally can be returned and extracted to the outside.

[0173] In order to increase the area of ​​the second electrode layer 280 and thereby improve the light extraction efficiency, it is preferable to form the coating layer 240 to consist of at least two layers.

[0174] A brief description of the aspects of the present disclosure described above is as follows.

[0175] A display device according to a first aspect of the present disclosure comprises a substrate having an emitting region and a non-emissive region; a cladding layer disposed on the substrate; a passivation layer disposed on the cladding layer and having at least one hole in the emitting region; a first electrode layer disposed on an upper surface of the passivation layer and located in a region other than the at least one hole; a light-emitting layer disposed on the first electrode layer and covering the cladding layer and the passivation layer in the at least one hole; and a second electrode layer disposed on the light-emitting layer.

[0176] In the display device according to the first aspect of the present disclosure, a thickness of the passivation layer may be greater than a thickness of the first electrode layer.

[0177] In the display device according to the first aspect of the present disclosure, the display device may further comprise: a contact portion passing through the passivation layer and the overcoat layer, wherein the first electrode layer and a connection pattern disposed on the substrate are electrically connected in the contact portion; and a bank layer disposed on the first electrode layer and filling the contact portion.

[0178] In the display device according to the first aspect of the present disclosure, the display device may further include a contact portion passing through the passivation layer and the overcoat layer, the first electrode layer and a connection pattern arranged on the substrate are electrically connected in the contact portion, and the light-emitting layer and the second electrode layer may be arranged in the contact portion according to a shape of the first electrode layer.

[0179] In the display device according to the first aspect of the present disclosure, the coating layer may be formed of at least two layers.

[0180] In the display device according to the first aspect of the present disclosure, the coating layer may include at least one concave portion that consists of a flat section and an inclined section surrounding the flat section, and the passivation layer may cover the inclined section and overlap at least a partial area of the flat section.

[0181] In the display device according to the first aspect of the present disclosure, the display device may further include: a contact section that passes through the passivation layer and the coating layer, wherein the first electrode layer and a connection pattern arranged on the substrate are electrically connected in the contact section; and a bank layer that is arranged on the first electrode layer and fills the contact section.

[0182] A display device according to a second aspect of the present disclosure comprises a substrate having an emitting region and a non-emissive region; a cladding layer disposed on the substrate; a first electrode layer disposed on the cladding layer, having at least one hole in the emitting region, and comprising an upper electrode layer and a lower electrode layer located below the upper electrode layer; a light-emitting layer disposed on the first electrode layer and covering the cladding layer and the first electrode layer in the at least one hole; and a second electrode layer disposed on the light-emitting layer.

[0183] In the display device according to the second aspect of the present disclosure, a thickness of the lower electrode layer may be smaller than a thickness of the upper electrode layer.

[0184] In the display device according to the second aspect of the present disclosure, an etching rate of the lower electrode layer may be higher than an etching rate of the upper electrode layer.

[0185] In the display device according to the second aspect of the present disclosure, the upper electrode layer may contain indium tin oxide, ITO, and the lower electrode layer may contain at least one material selected from transparent conductive oxides or translucent metals having a higher etching rate than ITO.

[0186] In the display device according to the second aspect of the present disclosure, the display device may further include: a contact portion passing through the overcoat layer, and the first electrode layer and a connection pattern disposed on the substrate are electrically connected in the contact portion; and a bank layer disposed on the first electrode layer and filling the contact portion.

[0187] In the display device according to the second aspect of the present disclosure, the display device may further include a contact portion passing through the overcoat layer, the first electrode layer and a connection pattern disposed on the substrate are electrically connected in the contact portion, and the light-emitting layer and the second electrode layer may be disposed in the contact portion according to a shape of the first electrode layer.

[0188] In the display device according to the second aspect of the present disclosure, the coating layer may be formed of at least two layers.

[0189] In the display device according to the second aspect of the present disclosure, the coating layer may include at least one concave part formed by a flat portion and an inclined portion surrounding the flat portion, and the lower electrode layer may cover the inclined portion and overlap at least a portion of the flat portion.

[0190] In the display device according to the second aspect of the present disclosure, the display device may further comprise: a contact portion passing through the overcoat layer, wherein the first electrode layer and a connection pattern disposed on the substrate are electrically connected in the contact portion; and a bank layer disposed on the first electrode layer and filling the contact portion.

[0191] A display device according to a third aspect of the present disclosure comprises a substrate; a coating layer disposed on the substrate; a passivation layer disposed on the coating layer and having at least one hole exposing a partial upper surface of the coating layer; a first electrode layer disposed on an upper surface of the passivation layer and exposing the at least one hole; a light-emitting layer disposed on the first electrode layer and in the at least one hole; and a second electrode layer disposed on the light-emitting layer.

[0192] The above description has been presented to enable those skilled in the art to implement and use the technical idea of ​​the present disclosure and has been given in the context of a specific application and its requirements. Various modifications, additions, and substitutions of the described embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the scope of the present disclosure. The above description and the accompanying drawings provide an example of the technical idea of ​​the present disclosure for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the technical idea of ​​the present disclosure. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] KR 10-2023-0157500

[0001]

Claims

[1] Display device comprising: a substrate (100) having an emitting region and a non-emitting region; a coating layer (240) disposed on the substrate (100); a passivation layer (300) disposed on the overcoat layer (240) and having at least one hole (H) in the emitting region; a first electrode layer (250) disposed on an upper surface of the passivation layer (300) and located in a region other than the at least one hole (H); a light-emitting layer (270) disposed on the first electrode layer (250) and covering the overcoat layer (240) and the passivation layer (300) in the at least one hole (H); and a second electrode layer (280) disposed on the light-emitting layer (270). [2] The display device according to claim 1, wherein a thickness of the passivation layer (300) is greater than a thickness of the first electrode layer (250). [3] A display device according to claim 1 or 2, further comprising: a contact portion (CNT) extending through the passivation layer (300) and the overcoat layer (240), wherein the first electrode layer (250) and a connection pattern (210) arranged on the substrate (100) are electrically connected in the contact portion (CNT); and a bank layer (260) disposed on the first electrode layer (250) and filling the contact portion (CNT). [4] A display device according to claim 1 or 2, further comprising: a contact portion (CNT) extending through the passivation layer (300) and the overcoat layer (240), wherein the first electrode layer (250) and a connection pattern (210) arranged on the substrate (100) are electrically connected in the contact portion (CNT), wherein the light-emitting layer (270) and / or the second electrode layer (280) are arranged in the contact section (CNT) according to a shape of the first electrode layer (250). [5] A display device according to any one of the preceding claims, wherein the coating layer (240) is formed from at least two layers (241, 242). [6] Display device according to one of the preceding claims, wherein the coating layer (240) comprises at least one concave part formed by a flat portion and an inclined portion surrounding the flat portion, and the passivation layer (300) covers the inclined portion and overlaps at least a portion of the flat portion. [7] Display device comprising: a substrate (100) having an emitting region and a non-emitting region; a coating layer (240) disposed on the substrate (100); a first electrode layer (250) disposed on the overcoat layer (240), having at least one hole (H) in the emitting region, and comprising an upper electrode layer (251) and a lower electrode layer (252) located beneath the upper electrode layer (251); a light-emitting layer (270) disposed on the first electrode layer (250) and covering the overcoat layer (240) and the first electrode layer (250) in the at least one hole (H); and a second electrode layer (280) disposed on the light-emitting layer (270). [8] The display device according to claim 7, wherein a thickness of the lower electrode layer (252) is less than a thickness of the upper electrode layer (251). [9] The display device according to claim 7 or 8, wherein an etching rate of the lower electrode layer (252) is higher than an etching rate of the upper electrode layer (251). [10] A display device according to any one of claims 7 to 9, wherein the upper electrode layer (251) contains indium tin oxide, ITO, and the lower electrode layer (252) contains at least one material selected from transparent conductive oxides or translucent metal having a higher etching rate than ITO. [11] A display device according to any one of claims 7 to 10, further comprising: a contact portion (CNT) extending through the coating layer (240), wherein the first electrode layer (250) and a connection pattern (210) arranged on the substrate (100) are electrically connected in the contact portion (CNT); and a bank layer (260) disposed on the first electrode layer (250) and filling the contact portion (CNT). [12] A display device according to any one of claims 7 to 10, further comprising: a contact portion (CNT) extending through the coating layer (240), wherein the first electrode layer (250) and a connection pattern (210) arranged on the substrate (100) are electrically connected in the contact portion (CNT), wherein the light-emitting layer (270) and the second electrode layer (280) are arranged in the contact portion (CNT) according to a shape of the first electrode layer (250). [13] A display device according to any one of claims 7 to 12, wherein the coating layer (240) is formed of at least two layers (241, 242). [14] Display device according to one of claims 7 to 13, wherein the coating layer (240) comprises at least one concave part formed of a flat portion and an inclined portion surrounding the flat portion, and the lower electrode layer (252) covers the inclined portion and overlaps at least a portion of the flat portion. [15] Display device comprising: a substrate (100); a coating layer (240) disposed on the substrate (100); a passivation layer (300) disposed on the overcoat layer (240) and having at least one hole (H) exposing a partial upper surface of the overcoat layer; a first electrode layer (250) disposed on an upper surface of the passivation layer (300) and exposing the at least one hole (H); a light-emitting layer (270) arranged on the first electrode layer (250) and in the at least one hole (H); and a second electrode layer (280) disposed on the light-emitting layer (270).

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