Micro oled micro display device and preparation method thereof

Abstract

A Micro OLED micro display device and a preparation method thereof belong to the technical field of OLED micro display, and the Micro OLED micro display device comprises a CMOS substrate, a light-emitting functional layer is arranged on the CMOS substrate, a packaging layer and a filter layer are sequentially arranged on the light-emitting functional layer, the packaging layer comprises inorganic packaging layer I, inorganic packaging layer II and an organic layer which is outward convex between the inorganic packaging layer I and the inorganic packaging layer II, and the organic layer is arranged around the edge of the filter layer, and the Micro OLED micro display device has the beneficial effects that not only the particle around the edge of the display area can be coated, but also the problem of optical crosstalk is improved, and the reliability of the product is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of OLED display devices, in particular to a Micro OLED micro display device and a preparation method thereof. BACKGROUND

[0002] Micro OLED (Organic Light Emitting Display) is a kind of micro OLED display technology, mainly applied to special military display (gun sighting scope, single soldier combat helmet display, pilot helmet, etc.) and civil consumer electronics field (AR, VR, micro projector, aerial photography, etc.), Micro OLED has the advantages of small size, light weight, low power consumption, high contrast ratio, high resolution, etc.

[0003] In the preparation process of OLED, the edge of the mask in the evaporation process is prone to produce particle at the edge position of the display area, the existence of the particle will pierce the encapsulation film layer, provide a water oxygen invasion path, and reduce the encapsulation reliability.

[0004] As shown in Figure 1 In large-size OLEDs such as mobile phones, computers, and televisions, the TFE layer 9 is generally stacked in an inorganic-organic-inorganic manner, the inorganic layer serves to block water and oxygen, and the organic layer has a thickness of about 10 μm, which is used to cover the particle. The difference between small-size Micro OLED panels and large-size OLEDs is that the pixel area of the former is smaller, and the FMM (fine metal mask) cannot be used to prepare the light-emitting layer in the evaporation process, so the separate evaporation of R / G / B light-emitting layers cannot be realized. Generally, the realization of colorization is white light + CF (filter layer), and in this structure, if the inorganic-organic-inorganic full-area stacking encapsulation method in large-size OLEDs is used, it will result in too thick encapsulation layer in the AA area (effective display area) and too far distance between the light-emitting layer and the CF layer, which is prone to cause light leakage effect. SUMMARY

[0005] To solve the above technical problems, the present application provides a Micro OLED micro display device and a preparation method thereof, which can not only cover the particles at the edge of the display area, but also will not reduce the optical performance of the product, and can improve the reliability of the product.

[0006] In order to achieve the above object, the technical scheme adopted by the present application to solve its technical problems is: the Micro OLED micro display device comprises a CMOS substrate, a light-emitting functional layer is arranged on the CMOS substrate, a packaging layer and a light filtering layer are sequentially arranged on the light-emitting functional layer, the packaging layer comprises an inorganic packaging layer I, an inorganic packaging layer II and an organic layer protruding outwardly between the inorganic packaging layer I and the inorganic packaging layer II, and the organic layer is arranged around the edge of the light filtering layer.

[0007] The material of the inorganic packaging layer I and the inorganic packaging layer II is the same, comprises one or a combination of Al2O3, TiO2, ATO, silicon nitride, SiON and silicon oxide, the thickness of the inorganic packaging layer I is 30-1000 nm, and the thickness of the inorganic packaging layer II is 30-1000 nm.

[0008] The material of the organic layer comprises acrylic or epoxy resin, and the thickness of the organic layer is 1-10 um.

[0009] The surface of the organic layer protruding outwardly is arranged in an arc shape.

[0010] The light-emitting functional layer comprises an anode layer and a pixel definition layer arranged on the surface of the CMOS substrate, and the upper surfaces of the anode layer and the pixel definition layer sequentially cover an OLED layer comprising a light-emitting layer, a cathode layer and a CPL layer.

[0011] The CMOS substrate is provided with a barrier wall in the circumferential direction, and the organic layer is arranged between the outer edge of the pixel definition layer and the barrier wall.

[0012] The barrier wall is arranged between the outer edge of the packaging layer and the outer edge of the light filtering layer, the distance between the barrier wall and the outer edge of the packaging layer is 180-220 um, the width of the barrier wall is 5-50 um, and the height of the barrier wall is 0.5-2 um.

[0013] The surface of the packaging layer is connected to the light filtering layer through an OC1 layer, and the surface of the light filtering layer sequentially covers an OC2 layer and a glass cover plate.

[0014] A preparation method of a Micro OLED micro display device comprises the following steps:

[0015] 1) an anode layer and a pixel definition layer are prepared on a CMOS substrate, and a barrier wall is prepared on the periphery of the CMOS substrate;

[0016] 2) an OLED layer is prepared by evaporation;

[0017] 3) an inorganic packaging layer I, an organic layer and an inorganic packaging layer II are sequentially prepared, so that the inorganic layer is located in the region between the barrier wall and the edge of the anode layer;

[0018] 4) subsequent yellow light and module processes are completed.

[0019] The pixel definition layer in the step 1) is prepared simultaneously with the barrier wall, and the preparation method comprises a coating-exposure-development-etching method, an inkjet printing method or a dispensing method; the method for preparing the inorganic encapsulation layer I and the inorganic encapsulation layer II in the step 3) comprises a gas deposition method of ALD and PECVD, and the method for preparing the organic layer comprises an inkjet printing method or a dispensing method; the photo-lithography process in the step 4) comprises sequentially preparing an OC1 layer, a filter layer and an OC2 layer on the inorganic encapsulation layer II, and the module process comprises bonding and cutting of a glass cover plate.

[0020] The beneficial effects of the present application are:

[0021] 1. The present application encapsulation layer comprising inorganic encapsulation layer I, inorganic encapsulation layer II and organic layer between them, two inorganic encapsulation layers cover the surface of the light-emitting layer, and the organic layer covers the periphery of the display device, which is arranged in a ring shape. This structure not only can encapsulate the edge particles, but also can improve the optical crosstalk problem and improve the reliability of the product due to the thin film layer and the close distance between the light-emitting layer and the filter layer.

[0022] 2. The present application sets the barrier wall to form a ring-shaped area between the barrier wall and the pixel definition layer, which provides a boundary for the preparation of the organic layer and ensures the accuracy of the preparation of the organic layer, effectively encapsulating the edge particles of the display device and improving the optical crosstalk problem. BRIEF DESCRIPTION OF DRAWINGS

[0023] The content expressed by each figure in the specification of the present application and the marks in the figures are briefly described as follows:

[0024] Figure 1 It is a structural schematic diagram of the existing Micro OLED micro display device;

[0025] Figure 2 It is a structural schematic diagram of the present application;

[0026] The marks in the above figures are as follows: 1. CMOS substrate, 2. light-emitting functional layer, 21. anode layer, 22. pixel definition layer, 23. OLED layer, 3. encapsulation layer, 31. inorganic encapsulation layer I, 32. inorganic encapsulation layer II, 33. organic layer, 4. barrier wall, 5. OC1 layer, 6. filter layer, 7. OC2 layer, 8. glass cover plate, 9. TFE layer. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments will be described clearly and completely in combination with the figures in the embodiments of the present application. The following embodiments are used to illustrate the present application, but not to limit the scope of the present application.

[0028] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] The specific implementation scheme of this invention is as follows: Figure 2 As shown, a Micro OLED microdisplay device includes a CMOS substrate 1, on which a light-emitting functional layer 2 is sequentially disposed. On the light-emitting functional layer 2, an encapsulation layer 3 and a filter layer 6 are sequentially disposed. The encapsulation layer 3 includes an inorganic encapsulation layer I 31, an inorganic encapsulation layer II 32, and an outwardly protruding organic layer 33 between them. The inorganic encapsulation layer I 31 and the inorganic encapsulation layer II 32 both cover the surface of the light-emitting functional layer 2. The organic layer 33 is arranged in a ring around the edge of the filter layer 6. This structure can not only cover the particles at the edge, but also improve the optical crosstalk problem and enhance the reliability of the product because the overall film layer of the display device is relatively thin and the light-emitting layer is close to the filter layer 6.

[0031] Specifically, the inorganic encapsulation layer I 31 and inorganic encapsulation layer II 32 are made of the same material, including one or more combinations of Al2O3, TiO2, ATO, silicon nitride, SiON, and silicon oxide. The thickness of inorganic encapsulation layer I 31 is 30-1000 nm, and the thickness of inorganic encapsulation layer II 32 is 30-1000 nm. The organic layer 33 is made of acrylic or epoxy resin, and the thickness of organic layer 33 is 1-10 μm. The convex surface of organic layer 33 is set as arc shape to ensure the preparation quality of other film layers covering organic layer 33.

[0032] Specifically, the light-emitting functional layer 2 comprises an anode layer 21 and a pixel definition layer 22 arranged on the surface of the CMOS substrate 1, and the upper surfaces of the anode layer 21 and the pixel definition layer 22 are sequentially covered by an OLED layer 23 comprising a light-emitting layer, a cathode layer and a CPL layer. The CMOS substrate 1 is circumferentially provided with a barrier wall 4, and the barrier wall 4 is specifically arranged between the outer edge of the packaging layer 3 and the outer edge of the filter layer 6. The distance between the barrier wall 4 and the outer edge of the packaging layer 3 is 180-220 um, the width of the barrier wall 4 is 5-50 um, and the height of the barrier wall 4 is 0.5-2 um. The barrier wall 4 can be made of metal, inorganic material, organic material or the like. The outer edge of the pixel definition layer 22 and the barrier wall 4 form an annular area, so that the organic layer 33 is located in the annular area, thereby providing a limit for the preparation of the organic layer 33 and ensuring the accuracy of the preparation of the organic layer 33. The barrier wall 4 can effectively encapsulate the particles at the edge of the display device and improve the problem of optical crosstalk.

[0033] Specifically, the surface of the packaging layer 3 is connected to the filter layer 6 through an OC1 layer 5, and the surface of the filter layer 6 is sequentially covered by an OC2 layer 7 and a glass cover plate 8, thereby realizing the assembly and manufacturing of the display device.

[0034] The preparation method of the Micro OLED micro display device comprises the following steps:

[0035] 1) Preparing the CMOS substrate 1: preparing a CMOS driving circuit on a silicon wafer substrate to form the CMOS substrate 1;

[0036] 2) Preparing the anode layer 21, the pixel definition layer 22 and the barrier wall 4: preparing the anode layer 21 and the pixel definition layer 22 on the CMOS substrate 1 by using an existing method; while preparing the pixel definition layer 22, a circle of barrier walls 4 is prepared on the periphery of the CMOS substrate 1. The position of the barrier wall 4 is required to be within the boundary of the packaging layer 3, so that the barrier wall 4 is located between the outer edge of the packaging layer 3 and the outer edge of the filter layer 6, and the distance between the barrier wall 4 and the outer edge of the packaging layer 3 is 180-220 um. The width of the barrier wall 4 is 5-50 um, and the height of the barrier wall 4 is 0.5-2 um. The barrier wall 4 can be made of metal, inorganic material, organic material or the like. The preparation method comprises the methods of coating, exposure, development, etching, inkjet printing or dispensing.

[0037] 3) Preparing the OLED layer 23: preparing the light-emitting layer, the cathode layer and the CPL layer by using an evaporation process. The CPL layer can effectively block water and oxygen in the external environment, thereby protecting the display device from water and oxygen corrosion.

[0038] 4) Preparation of encapsulation layer 3: preparation of inorganic encapsulation layer I 31: the preparation method includes but is not limited to vapor deposition method of ALD, PECVD, the film quality is one or several combinations between Al2O3, TiO2, ATO, silicon nitride, SiON, silicon oxide film layer, the thickness is 30nm-1000nm; preparation of organic layer 33: the organic layer 33 is located between the two fences composed of the above stop wall 4 and the edge of the pixel definition layer 22, in the annular state around the display area, the preparation method includes but is not limited to inkjet printing, dispenser, the film quality is acrylic or epoxy resin organic material, the thickness is 1μm-10μm; preparation of inorganic encapsulation layer II 32: the preparation method includes but is not limited to vapor deposition method of ALD, PECVD, the film quality is one or several combinations between Al2O3, TiO2, ATO, silicon nitride, SiON, silicon oxide film layer, the thickness is 30nm-1000nm.

[0039] 5) Complete subsequent yellow light and module process: the yellow light process includes preparation of OC1 layer 5, filter layer 6 and OC2 layer 7 on inorganic encapsulation layer II 32 in turn, the module process includes the attachment and cutting of glass cover plate 8.

[0040] In summary, the present application is designed to include inorganic encapsulation layer I, inorganic encapsulation layer II and organic layer between them, two layers of inorganic encapsulation layer are covered on the surface of the light emitting layer, the organic layer is arranged in the annular area between the stop wall and the pixel definition layer, and is arranged in the annular shape, this structure not only can cover the edge particle, but also because the film layer is thin, the light emitting layer is close to the filter layer, the optical crosstalk problem is improved, and the reliability of the product is improved.

[0041] The above is only to illustrate some principles of the present application, and the present application is not limited to the specific structure and application range shown and described, so all possible corresponding modifications and equivalents belong to the patent scope of the present application.

Claims

1. A Micro OLED microdisplay device, characterized in that, The system includes a CMOS substrate, on which a light-emitting functional layer is disposed, and an encapsulation layer and a filter layer are disposed sequentially on the light-emitting functional layer. The encapsulation layer includes an inorganic encapsulation layer I, an inorganic encapsulation layer II, and an outwardly protruding organic layer between them. The organic layer is arranged around the edge of the filter layer. The inorganic encapsulation layer I has a thickness of 30~1000nm, the inorganic encapsulation layer II has a thickness of 30~1000nm, the organic layer has a thickness of 1~10um, and the convex surface of the organic layer is set to be arc-shaped. The light-emitting functional layer includes an anode layer and a pixel definition layer disposed on the surface of the CMOS substrate. The upper surfaces of the anode layer and the pixel definition layer are sequentially covered with an OLED layer including a light-emitting layer, a cathode layer, and a CPL layer. A barrier wall is disposed on the CMOS substrate along the circumferential direction. The organic layer is disposed between the outer edge of the pixel definition layer and the barrier wall. The barrier wall is disposed between the outer edge of the encapsulation layer and the outer edge of the filter layer. The distance between the barrier wall and the outer edge of the encapsulation layer is 180~220um. The width of the barrier wall is 5~50um and the height is 0.5~2um.

2. The Micro OLED microdisplay device according to claim 1, characterized in that: The inorganic encapsulation layer I and inorganic encapsulation layer II are made of the same material, including one or more of Al2O3, TiO2, ATO, silicon nitride, SiON, and silicon oxide.

3. The Micro OLED microdisplay device according to claim 1, characterized in that: The organic layer is made of materials including acrylic or epoxy resin.

4. The Micro OLED microdisplay device according to claim 1, characterized in that: The surface of the encapsulation layer is connected to the filter layer through the OC1 layer, and the surface of the filter layer is sequentially covered by the OC2 layer and the glass cover.

5. A method for fabricating a Micro OLED microdisplay device as described in any one of claims 1 to 4, characterized in that, Includes the following steps: 1) An anode layer and a pixel definition layer are fabricated on a CMOS substrate, and a barrier is fabricated around the CMOS substrate. 2) OLED layer fabrication by vapor deposition; 3) Prepare inorganic encapsulation layer I, organic layer and inorganic encapsulation layer II in sequence, so that the inorganic layer is located in the area between the barrier and the edge of the pixel definition layer; 4) Complete the subsequent photolithography and module manufacturing processes.

6. The method for fabricating a Micro OLED microdisplay device according to claim 5, characterized in that: In step 1), the pixel definition layer and the barrier are prepared simultaneously, and the preparation methods include coating-exposure-development-etching, inkjet printing or dispensing. In step 3), the methods for preparing inorganic encapsulation layer I and inorganic encapsulation layer II include ALD and PECVD vapor deposition, and the methods for preparing organic layers include inkjet printing or dispensing. In step 4), the photolithography process includes sequentially preparing OC1 layer, filter layer and OC2 layer on inorganic encapsulation layer II, and the module process includes bonding and cutting of glass cover.

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