An OLED display device and a manufacturing method thereof

Abstract

The application relates to the technical field of nanophotonics, in particular to an OLED display device and a manufacturing method thereof, which comprises an OLED substrate, a total reflection mirror layer located above the OLED substrate, wherein the total reflection mirror layer comprises a super surface structure, and the super surface structure is a cylindrical array nano structure; a flat layer located above the total reflection mirror layer; an anode located above the flat layer; a light-emitting layer located above the anode; a cathode located above the light-emitting layer; and a cover layer located above the cathode. The OLED display device improves the light-emitting efficiency, improves the color purity of displayed three-color light, enhances the resolution, and improves the user experience.

Description

Technical Field

[0001] This invention relates to the field of nanophotonics technology, and more particularly to an OLED display device and its manufacturing method. Background Technology

[0002] In the era of full-screen displays in electronic devices such as mobile phones, OLED (Organic Light-Emitting Diode) displays have been widely used and extensively researched. Currently, in existing OLED displays, white light is often used to illuminate the red, green, and blue light-emitting layers, causing the OLED display to emit red, green, and blue light. This results in the low luminous efficiency of existing OLED displays. Summary of the Invention

[0003] This application provides an OLED display device and its manufacturing method, which solves the technical problem of low luminous efficiency in existing OLED display devices and achieves technical effects such as improving luminous efficiency, improving the color purity of the displayed three colors, enhancing resolution, and improving user experience.

[0004] In a first aspect, embodiments of the present invention provide an OLED display device, comprising:

[0005] OLED substrate;

[0006] A total reflection mirror layer located on the OLED substrate, wherein the total reflection mirror layer includes a metasurface structure, and the metasurface structure is a cylindrical array nanostructure;

[0007] A flat layer located above the total reflection mirror layer;

[0008] The anode is located above the planar layer;

[0009] A light-emitting layer located above the anode;

[0010] The cathode located above the light-emitting layer;

[0011] A capping layer located above the cathode.

[0012] Preferably, the total reflection mirror layer further includes an aluminum thin film, which is located on the OLED substrate, and the metasurface structure is located on the aluminum thin film.

[0013] Preferably, the cylindrical array nanostructure exhibits a modulated phase of surface plasmon resonance.

[0014] Preferably, the cylindrical array nanostructure comprises multiple cylindrical arrays arranged periodically, and each of the multiple cylindrical arrays is a square array.

[0015] Preferably, each cylindrical array comprises a plurality of cylinders, the diameter of which ranges from 60 nanometers to 100 nanometers.

[0016] Preferably, the height of the cylinder is in the range of 40 nanometers to 60 nanometers.

[0017] Preferably, in each cylindrical array, the distance between the centers of adjacent cylinders ranges from 175 nanometers to 185 nanometers.

[0018] Preferably, the anode is made of tin-doped indium oxide.

[0019] Based on the same inventive concept, in a second aspect, the present invention also provides a method for manufacturing an OLED display device, comprising:

[0020] A total reflection mirror layer is formed on an OLED substrate, wherein the total reflection mirror layer includes a metasurface structure, and the metasurface structure is a cylindrical array nanostructure.

[0021] A planarization layer is formed on the total reflection mirror layer;

[0022] An anode is formed on the flat layer;

[0023] A light-emitting layer is formed on the anode;

[0024] A cathode is formed on the light-emitting layer;

[0025] A capping layer is formed on the cathode.

[0026] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0027] In this embodiment of the invention, a total internal reflection mirror layer is formed on an OLED substrate. The total internal reflection mirror layer includes a metasurface structure, which is a cylindrical array nanostructure, to achieve a modulated phase of surface plasmon resonance. Next, a planarization layer, an anode, a light-emitting layer, a cathode, and a capping layer are sequentially formed on the metasurface structure. The OLED display device of this embodiment is compatible with conventional semiconductor processes and has a simple manufacturing process. Compared with conventional color-filtered white OLEDs, the OLED display device of this embodiment provides a higher luminous efficiency, higher color purity, and higher resolution. Therefore, the OLED display device of this embodiment improves luminous efficiency, enhances the color purity of the displayed three colors, and improves resolution. Attached Figure Description

[0028] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0029] Figure 1 A schematic diagram of the structure of an OLED display device according to an embodiment of the present invention is shown;

[0030] Figure 2 A top view of the metasurface structure in an embodiment of the present invention is shown;

[0031] Figure 3 A schematic diagram of the structure of the OLED base and aluminum film in an embodiment of the present invention is shown;

[0032] Figure 4 A schematic diagram of the PMMA photoresist located on an aluminum film in an embodiment of the present invention is shown.

[0033] Figure 5 This diagram illustrates a structural schematic of exposing a cylindrical array on PMMA photoresist in an embodiment of the present invention.

[0034] Figure 6 A schematic diagram of aluminum evaporation in a cylindrical array is shown in an embodiment of the present invention;

[0035] Figure 7 A schematic diagram of the structure for forming a metasurface structure is shown in an embodiment of the present invention;

[0036] Figure 8 A flowchart illustrating the steps of a method for manufacturing an OLED display device according to an embodiment of the present invention is shown. Detailed Implementation

[0037] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0038] Example 1

[0039] The first embodiment of the present invention provides an OLED (Organic Light-Emitting Diode) display device, such as... Figure 1 As shown, it includes:

[0040] OLED substrate 110;

[0041] A total reflection mirror layer 120 is located on the OLED substrate 110, wherein the total reflection mirror layer 120 includes a metasurface structure 122, and the metasurface structure 122 is a cylindrical array nanostructure.

[0042] A planarization layer 130 located above the total reflection mirror layer 120;

[0043] Anode 140 located above the planarization layer 130;

[0044] The light-emitting layer 150 is located above the anode 140;

[0045] Cathode 160 located above the light-emitting layer 150;

[0046] A capping layer 170 is located above the cathode 160.

[0047] The OLED substrate 110 is made of materials including, but not limited to, silicon oxide. The total reflection mirror layer 120 also includes an aluminum thin film 121, which is located on the OLED substrate 110, and the metasurface structure 122 is located on the aluminum thin film 121.

[0048] Specifically, the metasurface structure 122 is a cylindrical array nanostructure, which forms the modulated phase of surface plasmon resonance. The cylindrical array nanostructure comprises multiple nanoscale cylindrical arrays arranged periodically, each of which is a square array. Each cylindrical array includes multiple cylinders, wherein the diameter of the cylinders ranges from 60 nanometers to 100 nanometers, and the height of the cylinders ranges from 40 nanometers to 60 nanometers. In each cylindrical array, the distance between the centers of two adjacent cylinders ranges from 175 nanometers to 185 nanometers, preferably 180 nanometers. Figure 2 In this context, P represents the distance between the centers of two adjacent cylinders.

[0049] by Figure 2 For example, Figure 2 This is a top view of metasurface structure 122, which is a cylindrical array nanostructure. Figure 2 There are four cylindrical arrays, all of which are square arrays. These four cylindrical arrays are denoted as cylindrical array A, cylindrical array B1, cylindrical array B2, and cylindrical array C, respectively. Figure 2As can be seen, A consists of 16 cylinders, and C consists of 16 cylinders; however, the cylinders in A and C have different diameters. B1 and B2 each consist of 9 cylinders, and the cylinders in B1 and B2 have the same diameter. In each of these four cylindrical arrays, the distance between the centers of two adjacent cylinders is 180 nanometers.

[0050] In addition, the metasurface structure 122 can be multiple Figure 2 The resulting structure, namely metasurface structure 122, can also be composed of multiple Figure 2 The structure shown is assembled from the above structures. Thus, metasurface structure 122 is based on... Figure 2 The structure shown is formed by a periodic arrangement. Therefore, the metasurface structure 122 forms a modulated phase of surface plasmon resonance.

[0051] In this embodiment, the planarization layer 130 located above the total reflection mirror layer 120 is made of a transparent dielectric material with a refractive index of approximately 1.5, such as PMMA photoresist. The thickness of the planarization layer 130 ranges from 15 nanometers to 25 nanometers, preferably 20 nanometers. The refractive index of the planarization layer 130 ranges from 1.4 to 1.6. The function of the planarization layer 130 is to fill the metasurface structure 122, which is formed as a convex cylinder, and to stabilize the anode 140 on the metasurface structure 122.

[0052] The anode 140 is made of indium tin-doped oxide, and its thickness ranges from 25 nm to 35 nm, preferably 30 nm. The light-emitting layer 150 is a red, green, and blue tri-color light-emitting layer, and its thickness ranges from 35 nm to 45 nm, preferably 40 nm. The cathode 160 is made of a silver-magnesium alloy, and its thickness ranges from 10 nm to 20 nm, preferably 15 nm. The capping layer 170 is made of materials including, but not limited to, glass, and its thickness ranges from 65 nm to 75 nm, preferably 70 nm. It should also be noted that the distance from the light-emitting layer 150 to the metasurface structure 122 is an integer multiple of half the wavelength of blue light, i.e., an integer multiple of 220 nm.

[0053] The principle of the OLED display device in this embodiment is as follows: the cathode 160, made of silver-magnesium alloy, can serve as a semi-transparent and semi-reflective mirror, and the semi-transparent and semi-reflective mirror layer 120 form a Fabry-Perot cavity. First, the frequency selection characteristics of the Fabry-Perot cavity, i.e., the cavity length, are used to select electromagnetic waves in the blue band. The cavity length is the distance from the light-emitting layer 150 to the metasurface structure 122. Furthermore, since the metasurface structure 122 forms a modulated phase of surface plasmon resonance, the phase of the reflected blue light wave is controlled by the metasurface structure 122, selecting green and red from the three primary colors, thus achieving red, green, and blue primary color emission. That is, by using cylindrical arrays of different periods and diameters in the metasurface structure 122, blue can be transformed into green and red. The result is that in the metasurface structure 122, the portion with the cylindrical array becomes other colors (red and green), while the portion without the elliptical cylindrical array remains blue, thus forming red, green, and blue primary color emission.

[0054] Furthermore, based on the principle of the OLED display device in this embodiment, different periodic arrangements and cylindrical arrays of different diameters result in different reflectance spectral characteristics, thus forming different colors of light. Researchers can fabricate cylindrical arrays of different periods and diameters as needed to meet the measurement requirements of wavelengths of different colors of light.

[0055] In this embodiment, the OLED display device is fabricated using a silicon oxide substrate as the OLED substrate 110. An aluminum thin film 121 is grown on the surface of the silicon oxide substrate by ion beam sputtering, as shown below... Figure 3 As shown. A 40nm thick PMMA (Poly Methyl Methacrylate) photoresist 180 is spin-coated onto the surface of the aluminum thin film 121, as shown. Figure 4 As shown.

[0056] Then, electron beam exposure is performed, with an electron beam voltage of 120 kV, a current of 200 pA, and an electron dose of 800 μC / cm. 2 Expose a cylindrical array on an electron beam photoresist, such as... Figure 5 As shown. In the cylindrical array, the distance between the centers of adjacent cylinders is 180 nanometers, and the diameter of the cylinders ranges from 60 nanometers to 100 nanometers. Then, 40 nanometers of aluminum are evaporated using an electron beam in the photoresist structure. Figure 6 The densely packed vertical stripes shown represent evaporated aluminum.

[0057] The exposed photoresist in the patterned area is removed using a wet stripping method to form a metasurface structure 122, such as... Figure 7 As shown in the figure. The wet degumming method uses acetone, anhydrous ethanol, and deionized water in sequence, and finally dries the product with N2.

[0058] After forming the metasurface structure 122, a 20-nanometer planarization layer 130 is formed on the metasurface. An anode 140, a light-emitting layer 150, a cathode 160, and a capping layer 170 are sequentially formed on the planarization layer 130.

[0059] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0060] In this embodiment, a total internal reflection mirror layer is formed on an OLED substrate. This layer includes a metasurface structure, which is a cylindrical array nanostructure, to achieve a modulated phase of surface plasmon resonance. Next, a planarization layer, an anode, a light-emitting layer, a cathode, and a capping layer are sequentially formed on the metasurface structure. The OLED display device of this embodiment is compatible with conventional semiconductor processes, simplifying the manufacturing process. Compared to conventional color-filtered white OLEDs, the OLED display device of this embodiment offers significantly higher luminous efficiency, higher color purity, and higher resolution. Therefore, the OLED display device of this embodiment improves luminous efficiency, enhances the color purity of the displayed three colors, and strengthens resolution.

[0061] Example 2

[0062] Based on the same inventive concept, the second embodiment of the present invention also provides a method for manufacturing an OLED display device, such as... Figure 8 As shown, it includes:

[0063] S201, A total reflection mirror layer is formed on an OLED substrate, wherein the total reflection mirror layer includes a metasurface structure, and the metasurface structure is a cylindrical array nanostructure;

[0064] S202, A planarization layer is formed on the total reflection mirror layer;

[0065] S203, forming an anode on the planar layer;

[0066] S204, a light-emitting layer is formed on the anode;

[0067] S205, a cathode is formed on the light-emitting layer;

[0068] S206, a capping layer is formed on the cathode.

[0069] Since the manufacturing method of the OLED display device described in this embodiment is the method used to implement the OLED display device in Embodiment 1 of this application, those skilled in the art can understand the specific implementation method and various variations of the manufacturing method of the OLED display device in this embodiment based on the OLED display device described in Embodiment 1 of this application. Therefore, how the manufacturing method of this OLED display device implements the OLED display device in Embodiment 1 of this application will not be described in detail here. As long as those skilled in the art implement the method used to implement the OLED display device in Embodiment 1 of this application, they are all within the scope of protection of this application.

[0070] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0071] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0072] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An OLED display device, characterized in that, include: OLED substrate; A total reflection mirror layer is located on the OLED substrate, wherein the total reflection mirror layer includes a metasurface structure, the metasurface structure being a cylindrical array nanostructure; the cylindrical array nanostructure includes multiple cylindrical arrays, with adjacent cylindrical arrays having different numbers of cylinders and cylinder diameters; A flat layer located above the total reflection mirror layer; The anode is located above the planar layer; A light-emitting layer located above the anode; The cathode located above the light-emitting layer; A capping layer located above the cathode.

2. The OLED display device as described in claim 1, characterized in that, The total reflection mirror layer also includes an aluminum thin film, which is located on the OLED substrate, and the metasurface structure is located on the aluminum thin film.

3. The OLED display device as described in claim 1, characterized in that, The cylindrical array nanostructure exhibits a modulated phase of surface plasmon resonance.

4. The OLED display device as described in claim 1, characterized in that, The cylindrical array nanostructure comprises multiple cylindrical arrays arranged periodically, and each of the multiple cylindrical arrays is a square array.

5. The OLED display device as described in claim 4, characterized in that, Each cylindrical array comprises multiple cylinders, the diameter of which ranges from 60 nanometers to 100 nanometers.

6. The OLED display device as described in claim 5, characterized in that, The height of the cylinder ranges from 40 nanometers to 60 nanometers.

7. The OLED display device as described in claim 5, characterized in that, In each of the cylindrical arrays, the distance between the centers of adjacent cylinders ranges from 175 nanometers to 185 nanometers.

8. The OLED display device as claimed in claim 1, characterized in that, The anode material includes: tin-doped indium oxide.

9. The OLED display device as claimed in claim 1, characterized in that, The cathode is made of a silver-magnesium alloy.

10. A method for manufacturing an OLED display device, characterized in that, include: A total reflection mirror layer is formed on an OLED substrate, wherein the total reflection mirror layer includes a metasurface structure, the metasurface structure being a cylindrical array nanostructure; the cylindrical array nanostructure includes multiple cylindrical arrays, with adjacent cylindrical arrays having different numbers of cylinders and cylinder diameters; A planarization layer is formed on the total reflection mirror layer; An anode is formed on the flat layer; A light-emitting layer is formed on the anode; A cathode is formed on the light-emitting layer; A capping layer is formed on the cathode.

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