A Micro OLED display structure and preparation method thereof

Abstract

The present invention discloses a Micro OLED display structure and a preparation method thereof, comprising a driving backplane, on which an anode and a hole transport functional layer are arranged, characterized in that: a flat layer is arranged on the hole transport functional layer, a gap pattern opposite to the anode is arranged on the flat layer, and a mesoporous light-emitting layer is arranged in the gap pattern. The Micro OLED display structure and the preparation method thereof of the present invention have a simple structure, can effectively reduce the occurrence of optical crosstalk, improve the overall display effect, and have strong practicality and good application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of display screens, and more specifically, relates to a Micro OLED display structure and a preparation method thereof. Background Art

[0002] With the advancement and development of science and technology, people have higher demands in the pursuit of display experience. In addition, wearable display devices make the method path feasible in the physical sense. The advent of the 5G era will solve the problem of data transmission. Therefore, in recent years, Micro OLED (Organic Light Emitting Display) has been called the dark horse of the next generation of display technology. It has been widely used in military markets such as machine-worn helmets, gun sights, night vision goggles, etc., and with the application of new technologies such as AR / VR and autonomous driving, Micro OLED microdisplays will usher in explosive growth.

[0003] In OLED displays, the light source is not surface light, but emits light in all directions. If the distance between two pixels is too close, the colors will crosstalk in the eyes of the observer, thus affecting the overall display effect. In the field of mobile phone displays, it is also possible to set a black matrix to limit light in other directions, but in Micro OLED displays, due to the limitations of materials and equipment, there is currently no good way to solve the problem of optical crosstalk at high resolution. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the prior art and to provide a Micro OLED display structure with a simple structure and capable of effectively reducing the occurrence of optical crosstalk, and a preparation method thereof.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: the provided Micro OLED display structure includes a driving backplane, on which an anode and a hole transport functional layer are arranged, and it is characterized in that: a flat layer is arranged on the hole transport functional layer, a gap pattern opposite to the anode is arranged on the flat layer, and a mesoporous light-emitting layer is arranged in the gap pattern.

[0006] In order to make the above technical solution more detailed and specific, the present invention also provides the following further preferred technical solutions to obtain satisfactory practical effects:

[0007] The mesoporous light-emitting layer is provided with a plurality of vertical holes which are arranged at intervals and pass through from top to bottom.

[0008] The thickness of the flat layer is consistent with the thickness of the mesoporous light-emitting layer.

[0009] The area of ​​the planar layer gap pattern is 10% larger than the metal area of ​​the anode.

[0010] An electron transport functional layer and a cathode are arranged on the flat layer and the mesoporous light-emitting layer.

[0011] A thin film packaging layer is provided on the electron transport functional layer and the cathode.

[0012] A color film layer is arranged on the thin film encapsulation layer, and a cover glass is arranged on the color film layer.

[0013] The preparation method of the Micro OLED display structure comprises the following steps: step 1: preparing a mesoporous layer; step 2: transferring the mesoporous layer prepared in step 1 to a hole transport functional layer to prepare the Micro OLED display structure.

[0014] A flat layer is coated on a glass substrate using a spin coating method; the flat layer is patterned using photolithography and dry etching, and a portion whose size matches the anode is removed; the patterned flat layer is immersed in glycerol, and Pluronic F127-TiO2 single micelles are added, and the pore size of the binary mesoporous material is controlled by adjusting the viscosity of glycerol.

[0015] On the driving backplane, a metal anode is prepared by photolithography and dry etching methods; a hole transport functional layer is prepared by evaporation; in an N2 environment, the mesoporous layer prepared in step one is transferred to the hole transport functional layer by nanoimprinting; the required light-emitting layer material is dropped into the mesoporous material by inkjet printing to form a mesoporous light-emitting layer; an electron transport functional layer and a cathode are prepared by evaporation; a thin film encapsulation layer is prepared on the electron transport functional layer and the cathode by ALD and CVD; a color film layer is prepared on the thin film encapsulation layer; and a glass cover is prepared on the color film layer.

[0016] Compared with the prior art, the present invention has the following advantages: the Micro OLED display structure and the preparation method thereof of the present invention have a simple structure, can effectively reduce the occurrence of optical crosstalk, improve the overall display effect, and have strong practicality and good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following is a brief description of the contents and symbols in the drawings of this specification:

[0018] Figure 1 This is a cross-sectional schematic diagram of the novel Micro OLED display structure of the present invention;

[0019] Figure 2 This is a schematic diagram of the preparation process of the mesoporous layer of the present invention;

[0020] Figure 3 It is a schematic cross-sectional view of the mesoporous light-emitting layer of the present invention.

[0021] Marked in the figure are: 1. driving backplane, 2. anode, 3. hole transport functional layer, 4. mesoporous light-emitting layer, 5. flat layer, 6. electron transport functional layer and cathode, 7. thin film encapsulation layer, 8. color film layer, 9. cover glass, 10. glass substrate. DETAILED DESCRIPTION

[0022] The specific implementation modes of the present invention will be further explained in detail below through the description of embodiments with reference to the accompanying drawings.

[0023] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0024] The Micro OLED display structure of the present invention is as follows: Figure 1 As shown in the figure, it includes a driving backplane 1, an anode 2 and a hole transport functional layer 3 are arranged on the driving backplane 1, a flat layer 5 is arranged on the hole transport functional layer 3, a gap pattern opposite to the anode 2 is arranged on the flat layer 5, and a mesoporous light-emitting layer 4 is arranged in the gap pattern; an electron transport functional layer and a cathode 6 are arranged on the flat layer 5 and the mesoporous light-emitting layer 4. The present invention greatly reduces the occurrence of optical crosstalk by arranging the mesoporous light-emitting layer 4 between the hole transport functional layer 3 and the electron transport functional layer to limit the light emission direction of the OLED.

[0025] In the present invention, Figure 3 As shown in , the mesoporous light-emitting layer 4 is provided with a plurality of vertical holes arranged at intervals and penetrating from top to bottom, so as to ensure that the light is emitted in a vertical direction and reduce the occurrence of optical crosstalk.

[0026] In the present invention, Figure 1 , 2 As shown in FIG. 1 , the thickness of the planar layer 5 is consistent with the thickness of the mesoporous light-emitting layer 4. The area of ​​the gap pattern of the planar layer 5 is 10% larger than the metal area of ​​the anode 2.

[0027] In the present invention, Figure 1 As shown in FIG. 1 , a thin film encapsulation layer 7 is provided on the electron transport functional layer and the cathode 6. A color film layer 8 is provided on the thin film encapsulation layer 7, and a cover glass 9 is provided on the color film layer 8.

[0028] In the present invention, the preparation method of the Micro OLED display structure includes the following steps: step 1: preparing a mesoporous layer, such as Figure 2As shown in ; Step 2: Transfer the mesoporous layer prepared in step 1 to the hole transport functional layer 3 to prepare a Micro OLED display structure.

[0029] In the present invention, step one: prepare a mesoporous layer; apply a flat layer 5 on a glass substrate 10 by spin coating; pattern the flat layer 5 by photolithography and dry etching, and remove a portion whose size matches the anode 2; soak the patterned flat layer in glycerol, and add Pluronic F127-TiO2 single micelles, and control the pore size of the two-dimensional mesoporous material by adjusting the viscosity of glycerol, preferably with a diameter of 100 nm, and dry the prepared one for use.

[0030] On the driving backplane 1, a metal anode 2 is prepared by photolithography and dry etching methods; a hole transport functional layer 3 is prepared by evaporation; in an N2 environment, the mesoporous layer prepared in step one is transferred to the hole transport functional layer 3 by nanoimprinting; the required light-emitting layer material is dropped into the mesoporous material by inkjet printing to form a mesoporous light-emitting layer; an electron transport functional layer and a cathode 6 are prepared by evaporation; a thin film encapsulation layer 7 is prepared on the electron transport functional layer and the cathode by ALD and CVD; a color film layer 8 is prepared on the thin film encapsulation layer 7; and a glass cover plate 9 is prepared on the color film layer 8.

[0031] Pluronic F127-TiO2 single micelle is a core-shell structure formed by wrapping the TiO2 material with Pluronic F127. At the same time, since Pluronic F127 can be dissolved in glycerol, when added to glycerol, the Pluronic F127 material on the periphery will be dissolved, leaving only the TiO2 material. In addition, the difference in glycerol viscosity can affect the chain curling degree of the Pluronic F127 material, that is, affect the distance between two adjacent TiO2 materials, thereby controlling the pore size of the mesoporous material.

[0032] Preparation method of Pluronic F127-TiO2 single micelles:

[0033] Pluronic F127 material can be purchased from the major chemical material portal website. In this experiment, it was purchased from SigmaAldrich, CAS number: 9003-11-6, MDL number: MFCD00082049, PubChem chemical substance number: 24897874.

[0034] Preparation method of Pluronic F127-TiO2 single micelle: Prepare A and B liquids, A liquid is composed of 17ml butyl titanate and 36ml anhydrous ethanol; B liquid is composed of 36ml anhydrous ethanol, 2.58g Pluronic F127, 1.5ml glacial acetic acid, and then 4mol / L hydrochloric acid is used to adjust the pH of B liquid to about 5. A liquid is added drop by drop to B liquid, and B liquid is vigorously stirred with a magnetic bar. During the dropping process, B liquid is always clear. After the dropwise addition is completed, continue stirring at 80°C for 20 minutes, let stand for 2 hours, and Pluronic F127-TiO2 single micelles can be obtained. By adjusting the viscosity of glycerol, the viscosity range is 150-300m.Pa.s, the pore size of the mesoporous material is controlled, and the diameter is preferably 100nm. The prepared material is dried for use.

[0035] Use inkjet printing to drop the required luminescent layer materials into the mesoporous material to form a mesoporous luminescent layer. Common red light materials include: rhodamine dyes, DCM, DCT, DCJT, DCJTB, DCJTI and TPBD, etc., green light materials include: coumarin dye Coumarin6, quinacridone (QA), coronene, aniline (naphthalimide), etc., blue light materials include: N-aromatic benzimidazoles; 1,2,4-triazole derivatives (TAZ); 1,3-4-oxadiazole derivatives OXD-(P-NMe2); distyrylarylene; BPVBi, etc.

[0036] Specific preparation method:

[0037] Step 1: Preparation method of mesoporous layer

[0038] The flat layer 5 is coated on the glass substrate by spin coating. The material may be, but is not limited to, PDMS polydimethylsiloxane (polyimide, polymethacrylate, ethylene oxide may also be selected). The thickness may be 50 to 100 nm, preferably 100 nm, and may be adjusted according to the thickness of the OLED light-emitting layer to be consistent with the thickness of the OLED light-emitting layer.

[0039] The flat layer 5 is patterned by photolithography + dry etching, and the size of the removed part matches the anode, preferably 8um×4um, which can be adjusted according to the size of the anode and needs to be 10% larger than the anode metal area.

[0040] The patterned flat layer 5 is immersed in glycerol, and self-assembled Pluronic F127-TiO2 single micelles are added. The pore size of the two-dimensional mesoporous material is controlled by adjusting the viscosity of glycerol, and the diameter is preferably 100 nm. The prepared material is dried for later use.

[0041] Step 2: Preparation method of Micro OLED light-emitting device.

[0042] On the driving backplane 1, a metal anode 2 is prepared by photolithography + dry etching method; a hole transport functional layer 3 is prepared by evaporation; in an N2 environment, nanoimprinting is used to transfer the material prepared in step one to the hole transport functional layer 3; inkjet printing is used to drop the required light-emitting layer material into the mesoporous material to form a mesoporous light-emitting layer 4; an electron transport functional layer and a cathode 6 are prepared by evaporation; ALD and CVD are used to prepare a thin film encapsulation layer 7 on the electron transport functional layer and the cathode; a color film layer 8 is prepared on the thin film encapsulation layer 7; and a glass cover plate 9 is prepared on the color film layer 8.

[0043] The Micro OLED display structure and preparation method thereof of the present invention have a simple structure, can effectively reduce the occurrence of optical crosstalk, and improve the overall display effect, and have strong practicality and good application prospects.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] The present invention is described above by way of example in conjunction with the accompanying drawings, but the present invention is not limited to the above manner. As long as various non-substantial improvements made using the method concept and technical solution of the present invention or direct applications to other occasions are made, they all fall within the protection scope of the present invention.

Claims

1. A Micro OLED display structure, comprising a driving backplane, on which an anode and a hole transport functional layer are provided, characterized in that: A flat layer is provided on the hole transport functional layer, a gap pattern opposite to the anode is provided on the flat layer, and a mesoporous light-emitting layer is provided in the gap pattern; a plurality of vertical holes arranged at intervals and penetrating from top to bottom are provided on the mesoporous light-emitting layer; the thickness of the flat layer is consistent with the thickness of the mesoporous light-emitting layer; The area of ​​the flat layer gap pattern is 10% larger than the metal area of ​​the anode; an electron transport functional layer and a cathode are arranged on the flat layer and the mesoporous light-emitting layer.

2. The Micro OLED display structure according to claim 1, characterized in that: A thin film packaging layer is provided on the electron transport functional layer and the cathode.

3. The Micro OLED display structure according to claim 2, characterized in that: A color film layer is arranged on the thin film encapsulation layer, and a cover glass is arranged on the color film layer.

4. The method for preparing a Micro OLED display structure according to any one of claims 1 to 3, characterized in that: Step 1: prepare a mesoporous layer; Step 2: transfer the mesoporous layer prepared in step 1 to the hole transport functional layer to prepare a MicroOLED display structure.

5. The method for preparing a Micro OLED display structure according to claim 4, characterized in that: A flat layer is coated on a glass substrate using a spin coating method; the flat layer is patterned using photolithography and dry etching, and a portion whose size matches the anode is removed; the patterned flat layer is immersed in glycerol, and Pluronic F127-TiO2 single micelles are added, and the pore size of the binary mesoporous material is controlled by adjusting the viscosity of glycerol.

6. The method for preparing a Micro OLED display structure according to claim 5, characterized in that: On the driving backplane, a metal anode is prepared by photolithography and dry etching; a hole transport functional layer is prepared by evaporation; in an N2 environment, the mesoporous layer prepared in step one is transferred to the hole transport functional layer by nanoimprinting; the required light-emitting layer material is dropped into the mesoporous material by inkjet printing to form a mesoporous light-emitting layer; an electron transport functional layer and a cathode are prepared by evaporation; a thin film encapsulation layer is prepared on the electron transport functional layer and the cathode by ALD and CVD; a color film layer is prepared on the thin film encapsulation layer; and a glass cover is prepared on the color film layer.

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