Display device and method for manufacturing a display device

Abstract

A display device and a method for manufacturing a display device including a first sub-pixel, a second sub-pixel, and a third sub-pixel are provided. The display device includes: a substrate; and the first to third sub-pixels disposed on the substrate. The first sub-pixel includes: a first anode electrode disposed on the substrate; and a hole transport layer, a red light-emitting material layer, a green light-emitting material layer, a blue light-emitting material layer, and an electron transport layer sequentially stacked on the first anode electrode. The second sub-pixel includes: a second anode electrode disposed on the substrate; and a hole transport layer, a green light-emitting material layer, a blue light-emitting material layer, and an electron transport layer sequentially stacked on the second anode electrode. The third sub-pixel includes: a third anode electrode disposed on the substrate; and a hole transport layer, a blue light-emitting material layer, and an electron transport layer sequentially stacked on the third anode electrode.

Description

Technical Field

[0001] The present invention relates to a display device and a method for manufacturing the display device. Background Technology

[0002] Compared to liquid crystal displays (LCDs), self-emissive organic light-emitting diodes (OLEDs) offer wider viewing angles and higher contrast ratios, and do not require a separate backlight, enabling lightweight and thin displays with advantages in power consumption. Furthermore, OLEDs can operate at low DC voltages, have fast response times, and, most notably, low manufacturing costs.

[0003] Recently, head-mounted display devices have been developed for realizing virtual reality (VR) or augmented reality (AR). Summary of the Invention

[0004] To improve the stereoscopic visual effect, realism, and immersion of images achieved in head-mounted displays, these devices require display panels for displaying high-resolution images.

[0005] To achieve high-resolution display panels, organic light-emitting display panels with a new structure have been developed, in which organic light-emitting elements are formed on a silicon substrate.

[0006] Traditionally, fine metal masks (FMMs) have been used to deposit different organic light-emitting materials that emit different colors in red, green, and blue subpixels. However, the use of FMMs has limitations in improving the resolution of organic light-emitting display panels.

[0007] Therefore, alternative solutions have been proposed, in which, to achieve high-resolution organic light-emitting display panels, white-light-emitting organic light-emitting elements are co-located in red, green, and blue sub-pixels. These white-light-emitting organic light-emitting elements have a cascaded structure, comprising two or more light-emitting stacks emitting different colors of light. A problem exists: the power consumption of high-resolution display panels including cascaded organic light-emitting elements increases.

[0008] The technical objective of this disclosure is to provide a display device that can provide users with high-resolution images and reduce power consumption.

[0009] The technical objective of this disclosure is to provide a method for manufacturing a high-resolution display device having red, green, and blue light-emitting elements without using a fine metal mask (FMM).

[0010] The purposes of this disclosure are not limited to those mentioned above. Other purposes and advantages not mentioned in this disclosure may be understood based on the following description and may be more clearly understood based on embodiments of this disclosure. Furthermore, it will be readily understood that the purposes and advantages of this disclosure may be achieved using the means or combinations thereof shown in the claims.

[0011] One aspect of this disclosure provides a display device comprising: a substrate; and a first sub-pixel, a second sub-pixel, and a third sub-pixel disposed on the substrate, wherein the first sub-pixel comprises: a first anode electrode disposed on the substrate; and a hole transport layer, a red light-emitting material layer, a green light-emitting material layer, a blue light-emitting material layer, and an electron transport layer sequentially stacked on the first anode electrode; wherein the second sub-pixel comprises: a second anode electrode disposed on the substrate; and a hole transport layer, a green light-emitting material layer, a blue light-emitting material layer, and an electron transport layer sequentially stacked on the second anode electrode; wherein the third sub-pixel comprises: a third anode electrode disposed on the substrate; and a hole transport layer, a blue light-emitting material layer, and an electron transport layer sequentially stacked on the third anode electrode.

[0012] Another aspect of this disclosure provides a method for manufacturing a display device including a first sub-pixel, a second sub-pixel, and a third sub-pixel. The method includes: providing a backplane substrate including a first anode electrode disposed in the first sub-pixel, a second anode electrode disposed in the second sub-pixel, and a third anode electrode disposed in the third sub-pixel; depositing a hole transport layer on the first anode electrode to the third anode electrode in the first sub-pixel to the third sub-pixel; depositing a red light-emitting material layer on the hole transport layer in the first sub-pixel to the third sub-pixel; removing the red light-emitting material layer from each of the second sub-pixel and the third sub-pixel; depositing a green light-emitting material layer in the first sub-pixel to the third sub-pixel; removing the green light-emitting material layer from the third sub-pixel; and depositing a blue light-emitting material layer in the first sub-pixel to the third sub-pixel.

[0013] According to embodiments of the present disclosure, a display device is implemented having a red light-emitting element, a green light-emitting element, and a blue light-emitting element, wherein a red light-emitting material layer, a green light-emitting material layer, and a blue light-emitting material layer are stacked in a first sub-pixel; a green light-emitting material layer and a blue light-emitting material layer are stacked in a second sub-pixel; and a blue light-emitting material layer is disposed in a third sub-pixel, and energy is allowed to be transferred from the blue light-emitting material layer to the green light-emitting material layer and from the green light-emitting material layer to the red light-emitting material layer, thereby providing a high-resolution image and reducing power consumption.

[0014] According to embodiments of this disclosure, a high-resolution display device having red, green, and blue light-emitting elements is manufactured without using a fine metal mask (FMM) by the following steps: depositing a red light-emitting material layer in a first sub-pixel to a third sub-pixel, and subsequently removing the red light-emitting material layer from the second and third sub-pixels; depositing a green light-emitting material layer in the first and third sub-pixels; then removing the green light-emitting material layer from the third sub-pixel; and then depositing a blue light-emitting material layer in the first and third sub-pixels.

[0015] The effects of this disclosure are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art based on the following description.

[0016] In addition to the effects described above, the specific effects of this disclosure will also be described below, along with the specific details of the implementation methods for carrying out this disclosure. Attached Figure Description

[0017] Figure 1 This is a schematic plan view of a display device according to an embodiment of the present disclosure.

[0018] Figure 2 It is along Figure 1 The cross-sectional view taken from line II-II.

[0019] Figure 3 The stacking structure of each sub-pixel in a display device according to an embodiment of the present disclosure is schematically shown.

[0020] Figures 4A to 4G A method for manufacturing a display device according to an embodiment of the present disclosure is illustrated schematically.

[0021] Figures 5A to 5C The energy levels of a sub-pixel of a display device according to an embodiment of the present disclosure are shown.

[0022] Figures 6A to 6C The composite distribution of each sub-pixel in the sub-pixels of a display device according to an embodiment of the present disclosure is shown.

[0023] Figure 7 The stacking structure of each sub-pixel in a display device according to an embodiment of the present disclosure is schematically shown.

[0024] Figure 8 The stacking structure of each sub-pixel in a display device according to an embodiment of the present disclosure is schematically shown. Detailed Implementation

[0025] The advantages and features of this disclosure, as well as the methods for achieving these advantages and features, will be discussed later in the appendix. Figure 1 The embodiments described in detail below will become apparent. However, this disclosure is not limited to the embodiments disclosed below, but can be implemented in various different forms. Therefore, these embodiments are described merely to complete this disclosure and to fully inform those skilled in the art of the scope of this disclosure.

[0026] For the sake of brevity and clarity, the elements in the accompanying drawings are not necessarily drawn to scale. The same reference numerals in different drawings denote the same or similar elements and therefore perform similar functions. Furthermore, for the sake of simplicity, descriptions and details of well-known steps and elements have been omitted. In addition, numerous specific details are set forth in the following detailed description of this disclosure to provide a thorough understanding of it. However, it will be understood that this disclosure can be practiced without these specific details. In other instances, well-known methods, processes, components, and circuits have not been described in detail to avoid unnecessarily obscuring aspects of this disclosure. Examples of various embodiments are further shown and described below. It will be understood that the description herein is not intended to limit the claims to the specific embodiments described. Rather, the description herein is intended to cover alternatives, modifications, and equivalents that may be included within the spirit and scope of this disclosure as defined by the appended claims.

[0027] The shapes, sizes, ratios, angles, numbers, etc. disclosed in the accompanying drawings illustrating embodiments of this disclosure are illustrative and are not limited thereto.

[0028] The terminology used herein is intended only to describe the purpose of particular embodiments and is not intended to limit the scope of this disclosure. As used herein, unless the context explicitly indicates otherwise, the singular constructs “a” and “an” are intended to include the plural constructs as well. It will also be understood that the terms “comprising,” “including,” “containing,” and “comprise” as used in this disclosure specify the presence of the stated features, integers, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, operations, elements, components, and / or portions thereof. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one” preceding the list of components may modify the entire list of components without modifying individual components within the list. Errors or tolerances may be present in the interpretation of numerical values, even when no explicit description of errors or tolerances is provided.

[0029] Furthermore, it will be understood that when a first element or layer is referred to as existing "on" a second element or layer, the first element may be directly disposed on the second element or may be indirectly disposed on the second element, wherein a third element or layer is disposed between the first element or layer and the second element or layer. It will be understood that when an element or layer is referred to as being "connected to" or "coupled to" another element or layer, it may be directly connected to or coupled to the other element or layer, or one or more intermediate elements or layers may exist therein. Additionally, it will be understood that when an element or layer is referred to as being "between" two elements or layers, it may be the only element or layer between the two elements or layers, or one or more intermediate elements or layers may exist.

[0030] Furthermore, as used herein, when a layer, membrane, region, plate, etc., is disposed "above" or "top" of another layer, membrane, region, plate, etc., the former can directly contact the latter, or the other layer, membrane, region, plate, etc., can be disposed between the former and the latter. As used herein, when a layer, membrane, region, plate, etc., is directly disposed "above" or "top" of another layer, membrane, region, plate, etc., the former directly contacts the latter, while the other layer, membrane, region, plate, etc., is not disposed between the former and the latter. Furthermore, as used herein, when a layer, membrane, region, plate, etc., is disposed "below" or "underneath" of another layer, membrane, region, plate, etc., the former can directly contact the latter, or the other layer, membrane, region, plate, etc., can be disposed between the former and the latter. As used herein, when a layer, membrane, region, plate, etc., is directly disposed "below" or "underneath" of another layer, membrane, region, plate, etc., the former directly contacts the latter, while the other layer, membrane, region, plate, etc., is not disposed between the former and the latter.

[0031] In descriptions of temporal relationships, such as "after," "following," or "before," another event may occur in between unless it is indicated that it is "directly after," "directly following," or "directly before."

[0032] When a particular implementation can be implemented differently, the functions or operations specified in a specific block can occur in a different order than that specified in the flowchart. For example, two consecutive blocks can actually be executed substantially simultaneously, or the two blocks can be executed in reverse order depending on the functions or operations involved.

[0033] It will be understood that although the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers, and / or periods, these elements, components, regions, layers, and / or periods should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, and / or period from another element, component, region, layer, and / or period. Therefore, without departing from the spirit and scope of this disclosure, a first element, component, region, layer, or period as described below may be referred to as a second element, component, region, layer, or period.

[0034] When implementation methods can be different, the functions or operations specified within a specific block can be executed in a different order than that specified in the flowchart. For example, two consecutive blocks can be executed substantially simultaneously, or the blocks can be executed in reverse order based on their associated functions or operations.

[0035] Features of the various embodiments of this disclosure can be combined with each other in part or in whole, and can be technically related to or operable on each other. Embodiments can be implemented independently of each other, or can be implemented together in an associated relationship.

[0036] When interpreting numerical values, unless there is a separate, explicit description, the value is interpreted to include a range of error.

[0037] Unless otherwise defined, all terms used herein, including technical and scientific terms, shall have the same meaning as commonly understood by one of ordinary skill in the art to which the inventive concept pertains. It will be further understood that terms such as those defined in common dictionaries shall be interpreted as having a meaning consistent with their meaning in the context of the relevant field, and shall not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0038] As used herein, terms such as “implementation,” “example,” and “aspect” should not be construed as making any aspect or design described superior or advantageous to other aspects or designs.

[0039] Furthermore, the term "or" means "inclusive or," not "exclusive or." That is, unless otherwise stated or explicitly stated in the context, the expression "x uses either a or b" means any of the natural inclusive permutations.

[0040] The terms used in the following description have been selected to be general and common in the relevant art. However, depending on the development and / or changes in technology, conventions, preferences of those skilled in the art, etc., other terms may exist besides these. Therefore, the terms used in the following description should not be construed as limiting the technical concept, but should be understood as examples of terms used to describe implementation methods.

[0041] Furthermore, in specific cases, the terminology may be arbitrarily chosen by the applicant, and in such cases, its detailed meaning will be described in the corresponding descriptive paragraphs herein. Therefore, the terminology used in the following description should be understood not only based on the name of the term, but also on its meaning and its context throughout the specific embodiments.

[0042] In a description of signal flow, for example, when a signal is delivered from node A to node B, this can include cases where the signal is transmitted from node A to node B via another node, unless the phrases "immediately transmitted" or "directly transmitted" are used.

[0043] Throughout this disclosure, unless otherwise stated, “A and / or B” means A, B or A and B, and unless otherwise stated, “C to D” means C (inclusive) to D (inclusive).

[0044] "At least one" should be understood as any combination including one or more of the listed components. For example, at least one of the first, second, and third components means not only the first, second, or third component, but also all combinations of two or more of the first, second, and third components.

[0045] In the following description, embodiments of the present disclosure will be illustrated using the accompanying drawings. For ease of explanation, the scale of each component shown in the drawings differs from its actual scale, and therefore, the present disclosure is not limited to the scales shown in the drawings.

[0046] As used herein, the first direction, second direction, and third direction, or the X-axis direction, Y-axis direction, and Z-axis direction, should not be interpreted merely as having a geometric relationship between each other in which the first direction, second direction, and third direction are perpendicular to each other or the X-axis direction, Y-axis direction, and Z-axis direction are perpendicular to each other, but can be interpreted as having a relationship between each other in which the first direction, second direction, and third direction are at 90 degrees to each other within the range where the configuration of this disclosure can be functionally operational. Intersecting at angles other than 0.5 or the X-axis, Y-axis and Z-axis directions intersecting each other at 90 degrees ( ). The geometric relationship between objects that intersect at angles other than those mentioned above.

[0047] In the following description, the display device according to embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0048] Figure 1 This is a schematic plan view of a display device according to an embodiment of the present disclosure. Figure 2 It is along Figure 1 The cross-sectional view taken from line II-II.

[0049] Reference Figure 1 and Figure 2 A display device according to embodiments of the present disclosure may include: a substrate SUB, a transistor TR, first to third insulating layers INS1, INS2 and INS3, first to third reflective electrodes RE1, RE2 and RE3, a first contact electrode CE1 and a second contact electrode CE2, a first contact via VA1 and a second contact via VA2, a first anode electrode to a third anode electrode AN1, AN2 and AN3, a dam layer BN, a red emitting layer REML, a green emitting layer GEML, a blue emitting layer BEML, a cathode electrode CT, and an encapsulation layer ENC. Figure 2 The substrate SUB, transistor TR, first to third insulating layers INS1, INS2 and INS3, first to third reflective electrodes RE1, RE2 and RE3, first contact electrode CE1 and second contact electrode CE2, first contact via VA1 and second contact via VA2, first to third anode electrodes AN1, AN2 and AN3, and dam layer BN can constitute the backplane substrate BPN.

[0050] The display device according to the embodiments of this disclosure can be implemented in a so-called top-emitting manner, wherein light emitted from the light-emitting layer is emitted in an upward direction away from the substrate.

[0051] The substrate SUB can be made of a semiconductor material such as silicon (Si). The substrate SUB can be a semiconductor substrate.

[0052] For example, a first sub-pixel SP1, a second sub-pixel SP2, and a third sub-pixel SP3 are arranged along the X direction on the substrate SUB. The first sub-pixel SP1 can emit red light, the second sub-pixel SP2 can emit green light, and the third sub-pixel SP3 can emit blue light. The arrangement order and orientation of the sub-pixels SP1, SP2, and SP3 can be changed.

[0053] A driving circuit, including various circuit lines, transistors (TRs), and capacitors, is disposed on the substrate SUB and in each of the sub-pixels SP1, SP2, and SP3. The circuit lines may include gate lines, data lines, power lines, and reference lines, and the transistors (TRs) may include switching transistors, driving transistors, and sensing transistors. For example, the transistors (TRs) can be formed on the substrate SUB using a CMOS process.

[0054] The first insulating layer INS1 can be disposed on the substrate SUB. The first insulating layer INS1 can be made of inorganic insulating material or organic insulating material. The first insulating layer INS1 can cover transistors TR, various circuit lines, capacitors, etc. disposed on the substrate SUB.

[0055] The first reflective electrode RE1 and the first contact electrode CE1 can be disposed on the first insulating layer INS1. The first reflective electrode RE1 can be disposed in the first sub-pixel SP1, and the first contact electrode CE1 can be disposed in the second sub-pixel SP2 and the third sub-pixel SP3, respectively.

[0056] The first contact via VA1 can be configured to extend through the first insulating layer INS1. The first contact via VA1 can be provided in each of, for example, the first contact region to the third contact regions CA1, CA2 and CA3.

[0057] In the first sub-pixel SP1, the first reflective electrode RE1 can be connected to the transistor TR via a first contact via VA1 extending through the first insulating layer INS1. In each of the second sub-pixel SP2 and the third sub-pixel SP3, the first contact electrode CE1 can be connected to the transistor TR via a first contact via VA1 extending through the first insulating layer INS1. In the first contact area CA1 of the first sub-pixel SP1, the first reflective electrode RE1 can be connected to the transistor TR via a first contact via VA1 extending through the first insulating layer INS1. In the second contact area CA2 of the second sub-pixel SP2, the first contact electrode CE1 can be connected to the transistor TR via a first contact via VA1 extending through the first insulating layer INS1. In the third contact area CA3 of the third sub-pixel SP3, the first contact electrode CE1 can be connected to the transistor TR via a first contact via VA1 extending through the first insulating layer INS1.

[0058] In the implementation, in the first sub-pixel SP1, the first reflective electrode RE1 and the first contact via VA1 can be integrally formed or integrally integrated with each other. In the second sub-pixel SP2, the first contact electrode CE1 and the first contact via VA1 can be integrally formed or integrally integrated with each other. In the third sub-pixel SP3, the first contact electrode CE1 and the first contact via VA1 can be integrally formed or integrally integrated with each other.

[0059] The first reflective electrode RE1 and the first contact electrode CE1 can be made of a metallic material with high reflectivity, such as silver (Ag), silver alloy, aluminum (Al), or aluminum alloy. The first contact via VA1 can include a metallic material.

[0060] The second insulating layer INS2 can be disposed on the first insulating layer INS1, and the second insulating layer INS2 can cover the first reflective electrode RE1 and the first contact electrode CE1.

[0061] The second insulating layer INS2 can be made of inorganic or organic insulating materials.

[0062] The second reflective electrode RE2 and the second contact electrode CE2 can be disposed on the second insulating layer INS2. The second reflective electrode RE2 can be disposed in the second sub-pixel SP2, and the second contact electrode CE2 can be disposed in the first sub-pixel SP1 and the third sub-pixel SP3 respectively.

[0063] The second contact via VA2 can be configured to extend through the second insulating layer INS2. Each of the second contact vias VA2 can be located in, for example, each of the first contact region to the third contact region CA1, CA2 and CA3.

[0064] In the first contact area CA1 of the first sub-pixel SP1, the second contact electrode CE2 can be connected to the first reflective electrode RE1 via a second contact via VA2 extending through the second insulating layer INS2. In the second contact area CA2 of the second sub-pixel SP2, the second reflective electrode RE2 can be connected to the first contact electrode CE1 via a second contact via VA2 extending through the second insulating layer INS2. In the third contact area CA3 of the third sub-pixel SP3, the second contact electrode CE2 can be connected to the first contact electrode CE1 via a second contact via VA2 extending through the second insulating layer INS2.

[0065] The second reflective electrode RE2 and the second contact electrode CE2 can be made of a metallic material with high reflectivity, such as silver (Ag), silver alloy, aluminum (Al), or aluminum alloy. The second contact via VA2 can include a metallic material.

[0066] In the implementation, in the first sub-pixel SP1, the second contact electrode CE2 and the second contact via VA2 can be integrally formed or integrally integrated with each other. In the second sub-pixel SP2, the second reflective electrode RE2 and the second contact via VA2 can be integrally formed or integrally integrated with each other. In the third sub-pixel SP3, the second contact electrode CE2 and the second contact via VA2 can be integrally formed or integrally integrated with each other.

[0067] The third insulating layer INS3 can be disposed on the second insulating layer INS2, and the third insulating layer INS3 can cover the second reflective electrode RE2 and the second contact electrode CE2.

[0068] The third insulating layer INS3 can be made of inorganic or organic insulating materials.

[0069] The first anode electrode AN1, the second anode electrode AN2, the third reflective electrode RE3, and the third anode electrode AN3 can be disposed on the third insulating layer INS3. The first anode electrode AN1 can be disposed in the first sub-pixel SP1, the second anode electrode AN2 can be disposed in the second sub-pixel SP2, and the third reflective electrode RE3 and the third anode electrode AN3 can be disposed in the third sub-pixel SP3.

[0070] In the third sub-pixel SP3, the third reflective electrode RE3 and the third anode electrode AN3 can be in contact with each other.

[0071] The third contact via VA3 can be configured to extend through the third insulating layer INS3. In one example, each of the third contact vias VA3 can be located in each of the first contact region to the third contact regions CA1, CA2 and CA3.

[0072] In the first contact area CA1 of the first sub-pixel SP1, the first anode electrode AN1 can be connected to the second contact electrode CE2 via a third contact via VA3 extending through the third insulating layer INS3. In the second contact area CA2 of the second sub-pixel SP2, the second anode electrode AN2 can be connected to the second reflective electrode RE2 via a third contact via VA3 extending through the third insulating layer INS3. In the third contact area CA3 of the third sub-pixel SP3, the third reflective electrode RE3 can be connected to the second contact electrode CE2 via a third contact via VA3 extending through the third insulating layer INS3.

[0073] In this embodiment, in addition to bringing the third reflective electrode RE3 and the third anode electrode AN3 into contact with each other, an additional insulating layer may be provided on the third reflective electrode RE3, and the first anode electrode to the third anode electrode AN1, AN2 and AN3 may be disposed on this insulating layer. In this case, the third reflective electrode RE3 and the third anode electrode AN3 may be connected to each other via additional contact vias.

[0074] The third reflective electrode RE3 can be made of a highly reflective metallic material such as silver (Ag), silver alloy, aluminum (Al), or aluminum alloy. The third contact via VA3 can include a metallic material. Each of the first to third anode electrodes AN1, AN2, and AN3 can be made of a transparent conductive material such as ITO and IZO, which are capable of transmitting light through them.

[0075] Each of the first to third anode electrodes AN1, AN2 and AN3 can be electrically connected to the source or drain of a driving transistor disposed on the substrate SUB.

[0076] A dam BN is disposed on the third insulating layer INS3 to cover the edge regions of each of the first to third anode electrodes AN1, AN2, and AN3. A portion of the upper surface of the first anode electrode AN1, exposed but not covered by the dam BN, can be a first light-emitting region EA1. A portion of the upper surface of the second anode electrode AN2, exposed but not covered by the dam BN, can be a second light-emitting region EA2. A portion of the upper surface of the third anode electrode AN3, exposed but not covered by the dam BN, can be a third light-emitting region EA3.

[0077] The dam BN can be made of inorganic insulating materials. In an embodiment, the dam BN can be made of organic insulating materials.

[0078] Different light-emitting layers in different sub-pixels can be configured to emit different colors of light. The first sub-pixel SP1 can emit red light, the second sub-pixel SP2 can emit green light, and the third sub-pixel SP3 can emit blue light.

[0079] The hole transport layer (HTL) can be jointly disposed in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. The hole transport layer (HTL) can be disposed on the first anode electrode to the third anode electrode AN1, AN2, and AN3, as well as on the embankment BN.

[0080] Hole transport layer (HTL) can be an inorganic hole transport layer. HTLs can be made of inorganic materials. Inorganic materials can include Ni derivatives, Cu derivatives, carbon-based materials, etc. Ni derivatives can include NiO. x Nickel sulfide carbon (NiSC) and copper-doped NiO x Cu derivatives may include copper iodide (CuI), CuO, Cu₂O, and CuO. x Materials include CuS, CuCrO2, CuGaO2, CuAlO2, Cu3SbS4, CuFeO2, CuSCN, Cu2ZnSnS4, CuBaSnS4, and CuInSe2. Carbon-based materials can include carbon, graphene oxide, reduced graphene oxide, and carbon nanotubes. Hole transport layers (HTLs) can include MoO2, MoO3, and VOCs. x V2O x WO x MoS2, Bi2S3, TeO x Bi2O3, Sb2O3, CoO x CrO x MnS, etc. To ensure a smooth supply of holes to the luminescent material layer, the hole mobility of the hole transport layer (HTL) is preferably 1 × 10⁻⁶. -3 cm 2 / V·sec or greater. Hole transport layers (HTLs) can also be made of copper phthalocyanine (CuPc).

[0081] A red emitting material layer REML can be disposed on the hole transport layer HTL in the first sub-pixel SP1. A green emitting material layer GEML can be disposed together in the first sub-pixel SP1 and the second sub-pixel SP2. The green emitting material layer GEML can be disposed on the red emitting material layer REML in the first sub-pixel SP1 and on the hole transport layer HTL in the second sub-pixel SP2. A blue emitting material layer BEML can be disposed together in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. In each of the first sub-pixel SP1 and the second sub-pixel SP2, the blue emitting material layer BEML can be disposed on the green emitting material layer REML, and in the third sub-pixel SP3, it can be disposed on the hole transport layer HTL. Each of the red emitting material layer REML, the green emitting material layer REML, and the blue emitting material layer BEML can be made of an organic material.

[0082] The following will refer to Figure 3 Describes the light-emitting stacking of the first subpixel to the third subpixel SP1, SP2 and SP3.

[0083] The electron transport layer (ETL) can be jointly disposed in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. The ETL can be disposed on the blue emitting material layer BEML. The ETL can be made of organic materials. The ETL can be made of carbazole, oxadiazole, triazole, phenanthroline, benzoxazole, benzothiazole, etc. However, the embodiments of this disclosure are not limited thereto.

[0084] The cathode electrode CT can be disposed on the electron transport layer ETL. Alternatively, the cathode electrode CT can be disposed together in the first to third sub-pixels SP1, SP2, and SP3.

[0085] The cathode electrode CT can be made of a semi-transparent conductive material. It can also be made of metallic materials such as alloys of magnesium (Mg) and silver (Ag), or magnesium (Mg) or silver (Ag). The cathode electrode CT can be formed in the form of a thin film with a thickness of several nanometers to tens of nanometers. Therefore, due to the repeated reflection and re-reflection of light between the cathode electrode CT and the first to third reflective electrodes RE1, RE2, and RE3, a microcavity effect can be obtained in the first to third sub-pixels SP1, SP2, and SP3.

[0086] According to embodiments of this disclosure, since all of the following can be configured to be different from each other, the first spacing between the first reflective electrode RE1 and the cathode electrode CT in the first sub-pixel SP1, the second spacing between the second reflective electrode RE2 and the cathode electrode CT in the second sub-pixel SP2, and the third spacing between the third reflective electrode RE3 and the cathode electrode CT in the third sub-pixel SP3, the light extraction efficiency and color purity of different colors of light (e.g., red, green, and blue light) in the first to third sub-pixels SP1, SP2, and SP3 can be improved due to the microcavity effect.

[0087] The encapsulation layer ENC can be placed on the cathode electrode CT. Figure 2 The encapsulation layer ENC protects the red luminescent material layer (REML), green luminescent material layer (GEML), and blue luminescent material layer (BEML) from external moisture. The encapsulation layer ENC may comprise inorganic and organic encapsulation layers alternately stacked on top of each other. The inorganic encapsulation layer may be made from aluminum oxide (Al₂O₃). x O y ), silicon oxide (SiO) x ), silicon nitride (SiN) x It is made from one of the following: silicon nitride oxide (SiON), etc.

[0088] Figure 3 The stacking structure of each sub-pixel in a display device according to an embodiment of the present disclosure is schematically shown.

[0089] Reference Figure 3 The light-emitting stack ST disposed in the first sub-pixel SP1 may include: a first reflective electrode RE1, a first anode electrode AN1 disposed on the first reflective electrode RE1, a second insulating layer INS2 and a third insulating layer INS3 disposed between the first reflective electrode RE1 and the first anode electrode AN1, a hole transport layer HTL disposed on the first anode electrode AN1, a red light-emitting material layer REML, a green light-emitting material layer GEML and a blue light-emitting material layer BEML stacked sequentially on the hole transport layer HTL, an electron transport layer ETL disposed on the blue light-emitting material layer BEML, and a cathode electrode CT disposed on the electron transport layer ETL.

[0090] The red luminescent material layer (REML) may include a red substrate and red dopant. The green luminescent material layer (GEML) may include a green substrate and green dopant. The blue luminescent material layer (BEML) may include a blue substrate and blue dopant.

[0091] The process of generating red light in the first sub-pixel SP1 will be described. In the first sub-pixel SP1, energy can be transferred from the blue emitting material layer BEML to the green emitting material layer GEML, and energy can be transferred from the green emitting material layer GMEL to the red emitting material layer REML.

[0092] When excitons are generated in the red host, the red host releases energy. The red dopant can absorb the energy released from the red host, and luminescence can occur due to the recombination of electrons and holes in the red dopant.

[0093] When excitons are generated in the green host, the green host releases energy. The green dopant absorbs the energy released from the green host and then releases energy again. The red host absorbs the energy released from the green dopant again and then re-emits energy. The red dopant can absorb the energy released from the red host, and due to the recombination of electrons and holes in the red dopant, luminescence can occur.

[0094] When excitons are generated in the blue host, the blue host releases energy. This energy is absorbed by the blue dopant, which in turn releases energy again. The green host absorbs the energy released from the blue dopant and then releases energy again. The green dopant absorbs the energy released from the green host and then releases energy again. The red host absorbs the energy released from the green dopant and then releases energy again. The red dopant can absorb the energy released from the red host, and due to the recombination of electrons and holes within the red dopant, luminescence can occur.

[0095] The energy transfer described above requires the following conditions.

[0096] The emission spectrum of the blue dopant and the absorption spectrum of the green host can at least partially overlap. The long-wavelength edge of the emission spectrum of the blue dopant can have a wavelength longer than the short-wavelength edge of the absorption spectrum of the green host. The emission spectrum of the green dopant and the absorption spectrum of the red host can at least partially overlap. The long-wavelength edge of the emission spectrum of the green dopant can have a wavelength longer than the short-wavelength edge of the absorption spectrum of the red host.

[0097] Each of the red, green, and blue bodies can be implemented as a single body or as a hybrid body consisting of N-type and P-type bodies mixed together. When each of the red, green, and blue bodies is implemented as a hybrid body, the material of the P-type body can be included in an amount of 20 wt% or less of the total body material. The hole mobility of the P-type body can be greater than or equal to 1 × 10⁻⁶. -6 cm 2 / V·sec, and less than 1×10 -4cm 2 / V·sec. The electron mobility of the N-type host can be 1×10⁻⁶. -4 cm 2 / V·sec or greater.

[0098] The second insulating layer INS2 and the third insulating layer INS3 disposed between the first reflective electrode RE1 and the first anode electrode AN1 can serve as the cavity control layer of the first sub-pixel SP1.

[0099] Red light generated in the red luminescent material layer REML can be emitted outward through the cathode electrode CT. Due to the microcavity effect between the first reflective electrode RE1 and the cathode electrode CT, the light extraction efficiency and color purity of the red light generated from the red luminescent material layer REML can be improved.

[0100] The light-emitting stack disposed in the second sub-pixel SP2 may include: a second reflective electrode RE2, a second anode electrode AN2 disposed on the second reflective electrode RE2, a third insulating layer INS3 disposed between the second reflective electrode RE2 and the second anode electrode AN2, a hole transport layer HTL disposed on the second anode electrode AN2, a green light-emitting material layer GEML and a blue light-emitting material layer BEML sequentially deposited on the hole transport layer HTL, an electron transport layer ETL disposed on the blue light-emitting material layer BEML, and a cathode electrode CT disposed on the electron transport layer ETL.

[0101] The green luminescent material layer GEML may include a green substrate and a green dopant. The blue luminescent material layer BEML may include a blue substrate and a blue dopant. The green luminescent material layer GEML and the blue luminescent material layer BEML disposed in the second sub-pixel SP2 may be the same as those disposed in the first sub-pixel SP1.

[0102] The process of generating green light in the second sub-pixel SP2 will be described. In the second sub-pixel SP2, energy can be transferred from the blue emitting material layer BEML to the green emitting material layer GEML.

[0103] When excitons are generated in the green host, the green host releases energy. The green dopant absorbs the energy released from the green host, and luminescence occurs when electrons and holes recombine in the green dopant.

[0104] When excitons are generated in the blue host, the blue host releases energy. This energy is absorbed by the blue dopant, which in turn releases energy again. The green host then absorbs the energy released from the blue dopant and releases energy again. The green dopant absorbs the energy released from the green host, and luminescence occurs when electrons and holes recombine within the green dopant.

[0105] The third insulating layer INS3, located between the second reflective electrode RE2 and the second anode electrode AN2, can serve as the cavity control layer for the second sub-pixel SP2.

[0106] Green light generated in the green luminescent material layer GEML can be emitted outward through the cathode electrode CT. Due to the microcavity effect between the second reflective electrode RE2 and the cathode electrode CT, the light extraction efficiency and color purity of the green light generated from the green luminescent material layer GEML can be improved.

[0107] The light-emitting stack disposed in the third sub-pixel SP3 may include: a third reflective electrode RE3, a third anode electrode AN3 disposed on the third reflective electrode RE3, a hole transport layer HTL disposed on the third anode electrode AN3, a blue light-emitting material layer BEML disposed on the hole transport layer HTL, an electron transport layer ETL disposed on the blue light-emitting material layer BEML, and a cathode electrode CT disposed on the electron transport layer ETL.

[0108] The blue emitting material layer (BEML) may include a blue body and a blue dopant. The blue emitting material layer (BEML) disposed in the third sub-pixel SP3 may be the same as the blue emitting material layer (BEML) disposed in the first sub-pixel SP1 and the second sub-pixel SP2.

[0109] The process of generating blue light in the third sub-pixel SP3 will be described.

[0110] When excitons are generated in the blue host, the blue host releases energy. The blue dopant absorbs the energy released from the blue host, and luminescence occurs when electrons and holes recombine in the blue dopant.

[0111] Blue light generated in the blue luminescent material layer BEML can be emitted outward through the cathode electrode CT. Due to the microcavity effect between the third reflective electrode RE3 and the cathode electrode CT, the light extraction efficiency and color purity of the blue light generated in the blue luminescent material layer BEML can be improved.

[0112] To generate the optimal microcavity effect in each sub-pixel, the spacing between each reflective electrode and the cathode electrode CT can be adjusted according to each sub-pixel. Therefore, the spacing between the first anode electrode AN1 and the first reflective electrode RE1 can be greater than the spacing between the second anode electrode AN2 and the second reflective electrode RE2.

[0113] Figures 4A to 4G A method for manufacturing a display device according to an embodiment of the present disclosure is illustrated schematically. Figures 4A to 4G The illustration shows the materials used to manufacture, such as Figure 3 The method of the display device shown.

[0114] Reference Figure 4A A backplane substrate BPN can be fabricated comprising a first anode electrode AN1 disposed in a first sub-pixel SP1, a second anode electrode AN2 disposed in a second sub-pixel SP2, and a third anode electrode AN3 disposed in a third sub-pixel SP3. Figure 2 Then, the hole transport layer HTL and the red emitting material layer REML can be co-deposited in the first to third sub-pixels SP1, SP2, and SP3, and on the first to third anode electrodes AN1, AN2, and AN3 of the backplane substrate BPN. The hole transport layer HTL is first deposited on the backplane substrate BPN (…). Figure 2 After the first anode electrode to the third anode electrodes AN1, AN2 and AN3 are deposited, the red luminescent material layer REML can be deposited on the hole transport layer HTL.

[0115] Reference Figure 4B and Figure 4C By irradiating the second sub-pixel SP2 and the third sub-pixel SP3 with a laser, the red emitting material layer REML can be selectively removed from the second sub-pixel SP2 and the third sub-pixel SP3. Therefore, the red emitting material layer REML can be formed on the hole transport layer HTL in the first sub-pixel SP1. The wavelength of the laser can be any wavelength. In one example, a laser with wavelengths of UV (355 nm), visible light (532 nm), or infrared light (1064 nm) can be used. Alternatively, nanosecond lasers, picosecond lasers, and femtosecond lasers can be used to ensure selective thermal properties of the hole transport layer HTL and the red emitting material layer REML.

[0116] Reference Figure 4DThe green luminescent material layer GEML can be co-deposited in the first to third sub-pixels SP1, SP2, and SP3. In the second sub-pixel SP2 and the third sub-pixel SP3, the green luminescent material layer GEML can be deposited on the hole transport layer HTL, and in the first sub-pixel SP1, the green luminescent material layer GEML can be deposited on the red luminescent material layer REML.

[0117] Reference Figure 4E and Figure 4F By irradiating the third sub-pixel SP3 with a laser, the green emitting material layer GEML can be selectively removed from SP3. Therefore, the green emitting material layer GEML can be formed on the hole transport layer HTL in the second sub-pixel SP2, and the green emitting material layer GEML can be formed on the red emitting material layer REML in the first sub-pixel SP1. The wavelength of the laser can be any wavelength. In one example, a laser with wavelengths of UV (355 nm), visible light (532 nm), or infrared light (1064 nm) can be used. Alternatively, nanosecond lasers, picosecond lasers, and femtosecond lasers can be used to ensure selective thermal properties of the hole transport layer HTL and the green emitting material layer GEML.

[0118] Reference Figure 4G The blue emitting material layer BEML can be co-deposited in the first to third sub-pixels SP1, SP2 and SP3. In the third sub-pixel SP3, the blue emitting material layer BEML can be deposited on the hole transport layer HTL, and in each of the first sub-pixel SP1 and the second sub-pixel SP2, the blue emitting material layer BEML can be deposited on the green emitting material layer GEML.

[0119] Return to reference Figure 3 The electron transport layer (ETL) and the cathode electrode (CT) can be deposited sequentially in the first sub-pixel to the third sub-pixel SP1, SP2 and SP3.

[0120] In embodiments of this disclosure, a hole transport layer (HTL) made of inorganic materials can be applied, allowing the difference in thermal properties between inorganic and organic materials to be used to selectively remove the light-emitting material layer made of organic materials via laser irradiation. Furthermore, in embodiments of this disclosure, the application of an inorganic hole transport layer (HTL) reduces or prevents degradation of the HTL due to laser irradiation.

[0121] Figures 5A to 5C The energy levels of a sub-pixel of a display device according to an embodiment of the present disclosure are shown. Figures 5A to 5C It schematically shows, as Figure 3The energy levels of the light-emitting material layers of the first to third sub-pixels SP1, SP2 and SP3 of the display device shown.

[0122] Reference Figure 5A In order to make it difficult for holes injected from the hole transport layer HTL to migrate from the red emitting material layer REML to the green emitting material layer GEML in the first sub-pixel SP1, preferably, the highest occupied molecular orbital (HOMO) energy level of the red host of the red emitting material layer REML is higher than that of the green host of the green emitting material layer GEML, and the highest occupied molecular orbital (HOMO) energy level of the red dopant of the red emitting material layer REML is higher than that of the green dopant of the green emitting material layer GEML. For example, the highest occupied molecular orbital (HOMO) energy level of each of the host and dopant of the red emitting material layer REML may be 0.3 eV or more higher than that of each of the host and dopant of the green emitting material layer GEML.

[0123] To make it difficult for holes to migrate from the green emitting material layer GEML to the blue emitting material layer BEML, preferably, the highest occupied molecular orbital (HOMO) energy level of the green host of the green emitting material layer GEML is higher than that of the blue host of the blue emitting material layer BEML, and the highest occupied molecular orbital (HOMO) energy level of the green dopant of the green emitting material layer GEML is higher than that of the blue dopant of the blue emitting material layer BEML. For example, the highest occupied molecular orbital (HOMO) energy level of each of the green host and green dopant of the green emitting material layer GEML can be 0.3 eV or more higher than that of each of the blue host and blue dopant of the blue emitting material layer BEML.

[0124] To facilitate the easy migration of electrons injected from the electron transport layer (ETL) from the blue emitting material layer (BEML) to the green emitting material layer (GEML), the lowest unoccupied molecular orbital (LUMO) level of the green host of the green emitting material layer (GEML) is lower than that of the blue host of the blue emitting material layer (BEML), and the lowest unoccupied molecular orbital (LUMO) level of the green dopant of the green emitting material layer (GEML) is lower than that of the blue dopant of the blue emitting material layer (BEML). In an embodiment, the lowest unoccupied molecular orbital (LUMO) level of each of the host and dopant in the green emitting material layer (GEML) may be equal to that of each of the host and dopant in the blue emitting material layer (BEML).

[0125] To facilitate the easy migration of electrons from the green emitting material layer GEML to the red emitting material layer REML, the lowest unoccupied molecular orbital (LUMO) energy level of the red host of the red emitting material layer REML can be lower than that of the green host of the green emitting material layer GEML, and the lowest unoccupied molecular orbital (LUMO) energy level of the red dopant of the red emitting material layer REML can also be lower than that of the green dopant of the green emitting material layer GEML. In an embodiment, the lowest unoccupied molecular orbital (LUMO) energy level of each of the host and dopant in the red emitting material layer REML can be equal to that of each of the host and dopant in the green emitting material layer GEML.

[0126] Therefore, recombination of electrons and holes can mainly occur in the red luminescent material layer REML of the first sub-pixel SP1, and red light can be emitted from the luminescent stack of the first sub-pixel SP1.

[0127] Reference Figure 5BIn the second sub-pixel SP2, to make it difficult for holes injected from the hole transport layer HTL to migrate from the green emitting material layer GEML to the blue emitting material layer BEML, the highest occupied molecular orbital (HOMO) level of the green host of the green emitting material layer GEML is higher than that of the blue host of the blue emitting material layer BEML, and the highest occupied molecular orbital (HOMO) level of the green dopant of the green emitting material layer GEML is higher than that of the blue dopant of the blue emitting material layer BEML. For example, the highest occupied molecular orbital (HOMO) level of each of the green host and green dopant of the green emitting material layer GEML can be 0.3 eV or more higher than that of each of the blue host and blue dopant of the blue emitting material layer BEML.

[0128] To facilitate the easy migration of electrons from the blue emitting material layer BEML to the green emitting material layer GEML, the lowest unoccupied molecular orbital (LUMO) energy level of the green host of the green emitting material layer GEMML can be lower than that of the blue host of the blue emitting material layer BEML, and the lowest unoccupied molecular orbital (LUMO) energy level of the green dopant of the green emitting material layer GEMML can also be lower than that of the blue dopant of the blue emitting material layer BEML. In an embodiment, the lowest unoccupied molecular orbital (LUMO) energy level of each of the green host and the green dopant of the green emitting material layer GEMML can be equal to that of each of the blue host and the blue dopant of the blue emitting material layer BEML.

[0129] Therefore, recombination of electrons and holes can mainly occur in the green luminescent material layer GEML of the second sub-pixel SP2, and green light can be emitted from the luminescent stack of the second sub-pixel SP2.

[0130] Reference Figure 5C Since the blue luminescent material layer BEML is deposited only in the third sub-pixel SP3, recombination of electrons and holes can occur in the blue luminescent material layer BEML of the third sub-pixel SP3, and blue light can be emitted from the luminescent stack of the third sub-pixel SP3.

[0131] Figures 6A to 6C The composite distribution of each sub-pixel in the sub-pixels of a display device according to an embodiment of the present disclosure is shown.

[0132] Reference Figure 6AIn the first sub-pixel SP1, in addition to designing the HOMO and LUMO energy levels of each of the red emitting material layer REML, the green emitting material layer GEML, and the blue emitting material layer BEML, the electron mobility in each of these layers is designed to be higher than the hole mobility, so that electron-hole recombination can primarily occur in the red emitting material layer REML of the first sub-pixel SP1. A small amount of electron-hole recombination can also occur in the green emitting material layer GEML in the first sub-pixel SP1, but due to energy transitions, light is ultimately emitted from the red emitting material layer REML. Therefore, red light can be emitted from the emitting stack of the first sub-pixel SP1.

[0133] Reference Figure 6B In the second sub-pixel SP2, in addition to designing the HOMO and LUMO energy levels of each of the luminescent material layers GEML and BEML, the electron mobility in each of the luminescent material layers GEML and BEML can be designed to be higher than the hole mobility, so that a greater number of recombinations of electrons and holes can occur in the green luminescent material layer GEML of the second sub-pixel SP2. Therefore, green light can be emitted from the luminescent stack of the second sub-pixel SP2.

[0134] Reference Figure 6C The recombination of electrons and holes can occur in the blue emitting material layer BEML in the third sub-pixel SP3. Therefore, blue light can be emitted from the emitting stack of the third sub-pixel SP3.

[0135] According to embodiments of the present disclosure, a display device including a red light-emitting element, a green light-emitting element, and a blue light-emitting element can be provided. A red light-emitting material layer, a green light-emitting material layer, and a blue light-emitting material layer are stacked in a first sub-pixel; a green light-emitting material layer and a blue light-emitting material layer are stacked in a second sub-pixel; and a blue light-emitting material layer is disposed in a third sub-pixel. Energy is allowed to be transferred from the blue light-emitting material layer to the green light-emitting material layer and from the green light-emitting material layer to the red light-emitting material layer, thereby providing the user with a high-resolution image and reducing power consumption.

[0136] Figure 7 The stacking structure of each sub-pixel in a display device according to an embodiment of the present disclosure is schematically shown.

[0137] Reference Figure 7The light-emitting stack disposed in the first sub-pixel SP1' may include: a first reflective electrode RE1, a first anode electrode AN1 disposed on the first reflective electrode RE1, a hole transport layer HTL disposed on the first anode electrode AN1, a red light-emitting material layer REML', a green light-emitting material layer GEML' and a blue light-emitting material layer BEML sequentially deposited on the hole transport layer HTL, an electron transport layer ETL disposed on the blue light-emitting material layer BEML, and a cathode electrode CT disposed on the electron transport layer ETL.

[0138] and Figure 3 The display devices used in the illustrated embodiments are different. Figure 7 The display device of the embodiment may not include the second insulating layer INS2 and the third insulating layer INS3, that is, the cavity control layer between the first reflective electrode RE1 and the first anode electrode AN1 is not included in the first sub-pixel SP1'. Therefore, in order to achieve the microcavity effect in the first sub-pixel SP1', Figure 7 Each of the red luminescent material layer REML' and the green luminescent material layer GEML' in the display device can be more than Figure 3 The red luminescent material layer REML and the green luminescent material layer GEML of the display device are each thicker. Figure 7 The red luminescent material layer REML' of the display device can be compared to Figure 3 The red luminescent material layer REML of the display device is thicker than the second insulating layer INS2. Figure 7 The green luminescent material layer GEML' of the display device can be compared to Figure 3 The green luminescent material layer GEML of the display device is thicker than the third insulating layer INS3.

[0139] The red light generated in the red luminescent material layer REML' can be emitted outward through the cathode electrode CT. Due to the microcavity effect between the first reflective electrode RE1 and the cathode electrode CT, the light extraction efficiency and color purity of the red light generated in the red luminescent material layer REML' can be improved.

[0140] The light-emitting stack disposed in the second sub-pixel SP2' may include: a second reflective electrode RE2, a second anode electrode AN2 disposed on the second reflective electrode RE2, a hole transport layer HTL disposed on the second anode electrode AN2, a green light-emitting material layer GEML' and a blue light-emitting material layer BEML sequentially deposited on the hole transport layer HTL, an electron transport layer ETL disposed on the blue light-emitting material layer BEML, and a cathode electrode CT disposed on the electron transport layer ETL.

[0141] and Figure 3 The display devices used in the illustrated embodiments are different. Figure 7The display device of the embodiment may not include the third insulating layer INS3, that is, the cavity control layer between the second reflective electrode RE2 and the second anode electrode AN2 is not included in the second sub-pixel SP2'. Therefore, in order to achieve the microcavity effect in the second sub-pixel SP2', Figure 7 The green luminescent material layer GEML' of the display device can be compared to Figure 3 The green luminescent material layer GEML in the display device is thicker. Figure 7 The green luminescent material layer GEML' of the display device can be compared to Figure 3 The green luminescent material layer GEML of the display device is thicker than the third insulating layer INS3.

[0142] The green light generated in the green luminescent material layer GEML' can be emitted outward through the cathode electrode CT. Due to the microcavity effect between the first reflective electrode RE1 and the cathode electrode CT, the light extraction efficiency and color purity of the green light generated in the green luminescent material layer GEML' can be improved.

[0143] The light-emitting stack disposed in the third sub-pixel SP3 may include: a third reflective electrode RE3, a third anode electrode AN3 disposed on the third reflective electrode RE3, a hole transport layer HTL disposed on the third anode electrode AN3, a blue light-emitting material layer BEML disposed on the hole transport layer HTL, an electron transport layer ETL disposed on the blue light-emitting material layer BEML, and a cathode electrode CT disposed on the electron transport layer ETL.

[0144] Figure 7 The thickness of the blue luminescent material layer BEML in the display device can be equal to Figure 3 The thickness of the blue emitting material layer BEML. In the first sub-pixel SP1', each of the red emitting material layer REML' and the green emitting material layer GEML' can be thicker than the blue emitting material layer BEML. In the second sub-pixel SP2', the green emitting material layer GEML' can be thicker than the blue emitting material layer BEML.

[0145] According to embodiments of the present disclosure, a display device is implemented having a red light-emitting element, a green light-emitting element, and a blue light-emitting element, wherein a red light-emitting material layer, a green light-emitting material layer, and a blue light-emitting material layer are stacked in a first sub-pixel, a green light-emitting material layer and a blue light-emitting material layer are stacked in a second sub-pixel, and a blue light-emitting material layer is disposed in a third sub-pixel, and energy is allowed to be transferred from the blue light-emitting material layer to the green light-emitting material layer and from the green light-emitting material layer to the red light-emitting material layer, thereby providing a high-resolution image and reducing power consumption.

[0146] Figure 8The stacking structure of each sub-pixel of a display device according to an embodiment of the present disclosure is schematically shown.

[0147] Reference Figure 8 The light-emitting stack disposed in the first sub-pixel SP1'' includes: a first reflective electrode RE1, a first anode electrode AN1 disposed on the first reflective electrode RE1, a first hole transport layer HTL1 disposed on the first anode electrode AN1, a first red light-emitting material layer REML1, a first green light-emitting material layer GEML1 and a first blue light-emitting material layer BEML1 sequentially deposited on the first hole transport layer HTL1, a first electron transport layer ETL1 disposed on the first blue light-emitting material layer BEML1, a charge generation layer CGL disposed on the first electron transport layer ETL1, a second hole transport layer HTL2 disposed on the charge generation layer CGL, a second red light-emitting material layer REML2, a second green light-emitting material layer GEML2 and a second blue light-emitting material layer BEML2 sequentially deposited on the second hole transport layer HTL2, a second electron transport layer ETL2 disposed on the second blue light-emitting material layer BEML2, and a cathode electrode CT disposed on the second electron transport layer ETL2.

[0148] The light-emitting stack disposed in the second sub-pixel SP2'' includes: a second reflective electrode RE2, a second anode electrode AN2 disposed on the second reflective electrode RE2, a first hole transport layer HTL1 disposed on the second anode electrode AN2, a first green light-emitting material layer GEML1 and a first blue light-emitting material layer BEML1 sequentially deposited on the first hole transport layer HTL1, a first electron transport layer ETL1 disposed on the first blue light-emitting material layer BEML1, a charge generation layer CGL disposed on the first electron transport layer ETL1, a second hole transport layer HTL2 disposed on the charge generation layer CGL, a second green light-emitting material layer GEML2 and a second blue light-emitting material layer BEML2 sequentially deposited on the second hole transport layer HTL2, a second electron transport layer ETL2 disposed on the second blue light-emitting material layer BEML2, and a cathode electrode CT disposed on the second electron transport layer ETL2.

[0149] The light-emitting stack disposed in the third sub-pixel SP3'' includes: a third reflective electrode RE3, a third anode electrode AN3 disposed on the third reflective electrode RE3, a first hole transport layer HTL1 disposed on the third anode electrode AN3, a first blue light-emitting material layer BEML1 disposed on the first hole transport layer HTL1, a first electron transport layer ETL1 disposed on the first blue light-emitting material layer BEML1, a charge generation layer CGL disposed on the first electron transport layer ETL1, a second hole transport layer HTL2 disposed on the charge generation layer CGL, a second blue light-emitting material layer BEML2 disposed on the second hole transport layer HTL2, a second electron transport layer ETL2 disposed on the second blue light-emitting material layer BEML2, and a cathode electrode CT disposed on the second electron transport layer ETL2.

[0150] Each of the first hole transport layer HTL1 and the second hole transport layer HTL2 can be connected with... Figure 3 The hole transport layer HTL is the same. Each of the first red luminescent material layer REML1 and the second red luminescent material layer REML2 can be with Figure 3 The red luminescent material layer REML is the same. Each of the first green luminescent material layer GEML1 and the second green luminescent material layer GEML2 can be the same as... Figure 3 The green luminescent material layer GEML is the same. Each of the first blue luminescent material layer BEML1 and the second blue luminescent material layer BEML2 can be the same as... Figure 3 The blue luminescent material layer BEML is the same.

[0151] exist Figure 8 In this embodiment, no cavity control layer is provided between the first reflective electrode RE1 and the first anode electrode AN1 of the first sub-pixel SP1'', and between the second reflective electrode RE2 and the second anode electrode AN2 of the second sub-pixel SP2''. In another embodiment, a second insulating layer INS2 and a third insulating layer INS3 may be provided between the first reflective electrode RE1 and the first anode electrode AN1 of the first sub-pixel SP1'', and a third insulating layer INS3 may be provided between the second reflective electrode RE2 and the second anode electrode AN2 of the second sub-pixel SP2''.

[0152] According to embodiments of the present disclosure, a display device having a red light-emitting element, a green light-emitting element, and a blue light-emitting element can be provided, wherein a red light-emitting material layer, a green light-emitting material layer, and a blue light-emitting material layer are stacked in a first sub-pixel, a green light-emitting material layer and a blue light-emitting material layer are stacked in a second sub-pixel, and a blue light-emitting material layer is disposed in a third sub-pixel, and energy is allowed to be transferred from the blue light-emitting material layer to the green light-emitting material layer and from the green light-emitting material layer to the red light-emitting material layer, thereby providing the user with a high-resolution image and reducing power consumption.

[0153] While some embodiments of this disclosure have been described above with reference to the accompanying drawings, this disclosure is not limited to these embodiments and can be implemented in various different forms. Those skilled in the art to which this disclosure pertains will understand that this disclosure can be implemented in other specific forms without altering the technical concept or essential characteristics of this disclosure. Therefore, it should be understood that the embodiments described above are not limiting in any way, but rather illustrative.

Claims

1. A display device, the display device comprising: substrate; as well as The first sub-pixel, the second sub-pixel, and the third sub-pixel are disposed on the substrate. The first sub-pixel includes: A first anode electrode, the first anode electrode being disposed on the substrate; and A hole transport layer, a red light-emitting material layer, a green light-emitting material layer, a blue light-emitting material layer, and an electron transport layer are sequentially stacked on the first anode electrode. The second sub-pixel includes: A second anode electrode, the second anode electrode being disposed on the substrate; and A hole transport layer, a green light-emitting material layer, a blue light-emitting material layer, and an electron transport layer are sequentially stacked on the second anode electrode. The third sub-pixel includes: A third anode electrode, the third anode electrode being disposed on the substrate; and A hole transport layer, a blue luminescent material layer, and an electron transport layer are stacked sequentially on the third anode electrode.

2. The display device according to claim 1, wherein, The hole transport layer in each of the first to the third sub-pixels is made of inorganic material.

3. The display device according to claim 1 or 2, wherein, The display device further includes: A first reflective electrode is disposed between the first anode electrode and the substrate. The second reflective electrode is disposed between the second anode electrode and the substrate.

4. The display device according to claim 3, wherein, The distance between the first anode electrode and the first reflective electrode is greater than the distance between the second anode electrode and the second reflective electrode.

5. The display device according to claim 3, wherein, A first insulating layer and a second insulating layer are disposed between the first anode electrode and the first reflective electrode, and The second insulating layer is disposed between the second anode electrode and the second reflective electrode.

6. The display device according to claim 3, wherein, The display device further includes: A third reflective electrode is disposed between the third anode electrode and the substrate.

7. The display device according to claim 1 or 2, wherein, In the first sub-pixel, each of the red and green luminescent material layers is thicker than the blue luminescent material layer. In the second sub-pixel, the green luminescent material layer is thicker than the blue luminescent material layer.

8. The display device according to claim 1 or 2, wherein, In each of the first to the third sub-pixels, the hole transport layer is a first hole transport layer; in each of the first to the third sub-pixels, the red emitting material layer is a first red emitting material layer; in each of the first to the third sub-pixels, the green emitting material layer is a first green emitting material layer; in each of the first to the third sub-pixels, the blue emitting material layer is a first blue emitting material layer; and in each of the first to the third sub-pixels, the electron transport layer is a first electron transport layer. The first sub-pixel further includes: A charge generation layer, wherein the charge generation layer is disposed on the first electron transport layer; and A second hole transport layer, a second red luminescent material layer, a second green luminescent material layer, a second blue luminescent material layer, and a second electron transport layer are sequentially stacked on the charge generation layer of the first sub-pixel. The second sub-pixel further includes: A charge generation layer, wherein the charge generation layer is disposed on the first electron transport layer; and A second hole transport layer, a second green luminescent material layer, a second blue luminescent material layer, and a second electron transport layer are sequentially stacked on the charge generation layer of the second sub-pixel. The third sub-pixel further includes: A charge generation layer, wherein the charge generation layer is disposed on the first electron transport layer; and A second hole transport layer, a second blue luminescent material layer, and a second electron transport layer are sequentially stacked on the charge generation layer of the third sub-pixel.

9. The display device according to claim 1 or 2, wherein, The emission spectrum of the blue dopant in the blue luminescent material layer at least partially overlaps with the absorption spectrum of the green matrix in the green luminescent material layer. The emission spectrum of the green dopant in the green luminescent material layer overlaps at least partially with the absorption spectrum of the red host in the red luminescent material layer.

10. The display device according to claim 1 or 2, wherein, The highest occupied molecular orbital (HOMO) energy level of the red host in the red luminescent material layer is higher than that of the highest occupied molecular orbital (HOMO) energy level of the green host in the green luminescent material layer, and The highest occupied molecular orbital (HOMO) energy level of the green host in the green luminescent material layer is higher than that of the highest occupied molecular orbital (HOMO) energy level of the blue host in the blue luminescent material layer.

11. The display device according to claim 1 or 2, wherein, The lowest unoccupied molecular orbital (LUMO) energy level of the red host of the red luminescent material layer is lower than the lowest unoccupied molecular orbital (LUMO) energy level of the green host of the green luminescent material layer, and The lowest unoccupied molecular orbital (LUMO) energy level of the green host of the green luminescent material layer is lower than that of the lowest unoccupied molecular orbital (LUMO) energy level of the blue host of the blue luminescent material layer.

12. A method for manufacturing a display device including a first sub-pixel, a second sub-pixel, and a third sub-pixel, the method comprising: A backplane substrate is provided, the backplane substrate including a first anode electrode disposed in a first sub-pixel, a second anode electrode disposed in a second sub-pixel, and a third anode electrode disposed in a third sub-pixel; A hole transport layer is deposited on the first anode electrode to the third anode electrode in the first sub-pixel to the third sub-pixel; A red luminescent material layer is deposited on the hole transport layer in the first sub-pixel to the third sub-pixel; Remove the red luminescent material layer from each of the second and third sub-pixels; A green luminescent material layer is deposited in the first sub-pixel to the third sub-pixel; Remove the green luminescent material layer from the third sub-pixel; as well as A blue luminescent material layer is deposited in the first sub-pixel to the third sub-pixel.

13. The method according to claim 12, wherein, The hole transport layer is made of inorganic materials.

14. The method according to claim 12, wherein, The removal of the red luminescent material layer and the removal of the green luminescent material layer are each performed by laser irradiation.

15. The method according to claim 12 or 13, wherein, The emission spectrum of the blue dopant in the blue luminescent material layer at least partially overlaps with the absorption spectrum of the green matrix in the green luminescent material layer. The emission spectrum of the green dopant in the green luminescent material layer overlaps at least partially with the absorption spectrum of the red host in the red luminescent material layer.

16. The method according to claim 12 or 13, wherein, The highest occupied molecular orbital (HOMO) energy level of the red host in the red luminescent material layer is higher than that of the highest occupied molecular orbital (HOMO) energy level of the green host in the green luminescent material layer, and The highest occupied molecular orbital (HOMO) energy level of the green host in the green luminescent material layer is higher than that of the highest occupied molecular orbital (HOMO) energy level of the blue host in the blue luminescent material layer.

17. The method according to claim 12 or 13, wherein, The lowest unoccupied molecular orbital (LUMO) energy level of the red host of the red luminescent material layer is lower than the lowest unoccupied molecular orbital (LUMO) energy level of the green host of the green luminescent material layer, and The lowest unoccupied molecular orbital (LUMO) energy level of the green host of the green luminescent material layer is lower than that of the lowest unoccupied molecular orbital (LUMO) energy level of the blue host of the blue luminescent material layer.

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