CN111628108B - Packaging structure, display panel, preparation method of display panel and display device - Google Patents

Abstract

The application discloses a packaging structure, a display panel, a preparation method of the display panel and a display device, wherein the packaging structure comprises a first inorganic layer, a second inorganic layer, an organic layer and a third inorganic layer which are sequentially stacked; the first inorganic layer comprises a plurality of bulges arranged at intervals, and the bulges are used for enabling one side of the second inorganic layer, which is deviated from the first inorganic layer, to form a concave-convex structure. Above-mentioned scheme, one side that deviates from first inorganic layer at the inorganic layer of second forms concave-convex structure, this concave-convex structure is equivalent to and carries out roughening treatment to the inorganic layer of second, the leveling performance that forms the organic solution on organic layer is relevant with the inorganic layer surface structure of second, the inorganic layer surface roughness of second, then the leveling performance of organic solution is just high, higher leveling performance makes organic solution can fill whole inorganic layer of second, avoided because of the regional organic solution disappearance of inorganic layer portion of second, the display brightness inequality (MURA) that causes, and the poor problem of later stage reliability.

Description

Packaging structure, display panel, preparation method of display panel and display device

Technical Field

The invention relates to the technical field of display, in particular to a packaging structure, a display panel, a preparation method of the display panel and a display device.

Background

An OLED (Organic Light Emitting Diode) refers to a Display device made of Organic semiconductor materials and Light Emitting materials, which emit Light when current flows through the Display device, and has advantages of large viewing angle, low power consumption, and the like compared with an LCD (Liquid Crystal Display).

The water-oxygen environment affects the optical performance and lifetime of the light-emitting material, so the light-emitting material needs to be packaged by a packaging structure to isolate the light-emitting material from water and oxygen. The commonly used packaging structure comprises an inorganic layer and an organic layer which are alternately arranged, and when the organic layer is formed on the inorganic layer, the organic solution in a part of the area is lost due to the limitation of the leveling property of the organic solution for forming the organic layer, so that the problem of uneven display brightness (MURA) exists.

Disclosure of Invention

The application is expected to provide a package structure, a display panel, a manufacturing method thereof and a display device, which are at least used for solving the problem of uneven display brightness in the prior art.

In a first aspect, the present invention provides a package structure, including a first inorganic layer, a second inorganic layer, an organic layer, and a third inorganic layer, which are sequentially stacked;

the first inorganic layer comprises a plurality of bulges arranged at intervals, and the bulges are used for enabling one side of the second inorganic layer, which is deviated from the first inorganic layer, to form a concave-convex structure.

As an implementation, the plurality of protrusions are uniformly arranged.

As an implementation manner, the protrusion is at least any one of a rectangular protrusion, a regular polygonal protrusion, a triangular protrusion, and a cross-shaped protrusion.

As an implementation manner, the arrangement density of the protrusions is 3% -30%.

As an implementation manner, the material of the first inorganic layer and the second inorganic layer is at least any one of SiNx, siOx, siON, and AlOx.

As an implementation manner, the material of the organic layer is at least any one of acrylic acid, polyacrylate, and polystyrene.

In a second aspect, the present invention provides a display panel, including a display substrate, where the display substrate includes a substrate, a thin film transistor layer, and a functional layer that are sequentially stacked, and the functional layer includes a first electrode layer, a pixel definition layer, a light emitting layer, and a second electrode layer;

the packaging structure is arranged on the second electrode layer and used for packaging the functional layer.

In a third aspect, the present invention provides a display device, including the display panel.

In a fourth aspect, the present invention provides a method for manufacturing the display panel, including:

sequentially forming a thin film transistor layer and a functional layer on a substrate, wherein the functional layer comprises a first electrode layer, a pixel definition layer, a light emitting layer and a second electrode layer;

forming a first inorganic layer on the second electrode layer, wherein the first inorganic layer comprises a plurality of bulges arranged at intervals;

forming a second inorganic layer on the first inorganic layer, wherein the plurality of protrusions are used for enabling one side of the second inorganic layer, which is far away from the first inorganic layer, to form a concave-convex structure;

forming an organic layer on the second inorganic layer;

a third inorganic layer is formed on the organic layer.

Above-mentioned scheme, through setting up first inorganic layer below the inorganic layer of second, and first inorganic layer comprises a plurality of archs that the interval set up, make one side that the inorganic layer of second deviates from first inorganic layer form concave-convex structure, this concave-convex structure is equivalent to and carries out roughening treatment to the inorganic layer of second, the leveling performance of the organic solution that forms the organic layer is relevant with the inorganic layer surface structure of second, the inorganic layer surface roughness of second, then the leveling performance of organic solution is just high, higher leveling performance makes organic solution can pave whole inorganic layer of second, avoided because of the regional organic solution of inorganic layer part of second lacks, the problem of the display luminance inequality (MURA) that causes.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

fig. 1 is a schematic structural diagram of a package structure according to an embodiment of the present invention;

FIG. 2 is a schematic view of the arrangement of the projections;

FIG. 3 is another schematic view of the arrangement of the protrusions;

FIG. 4 is a schematic view of the arrangement of bumps of another structure;

FIG. 5 is a schematic structural diagram of a display panel according to an embodiment of the present invention

Fig. 6 is a flowchart illustrating a process of manufacturing a display panel according to an embodiment of the present invention.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.

It should be noted that, in the present application, the embodiments and features of the embodiments may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

As shown in fig. 1, the present invention according to an embodiment of the present invention provides an encapsulation structure, which includes a first inorganic layer 1, a second inorganic layer 2, an organic layer 4, and a third inorganic layer 5, which are sequentially stacked; the first inorganic layer 1 includes a plurality of protrusions 6 disposed at intervals, and the plurality of protrusions 6 are used to form the concave-convex structure 3 on a side of the second inorganic layer 2 away from the first inorganic layer 1.

Generally, the organic layer 4 has high water-oxygen barrier properties.

For example, but not limited to, the first inorganic layer 1, the second inorganic layer 2, and the third inorganic layer 5 may each have a thickness of 0.5 micrometers or less, and the organic layer 4 may have a thickness of 5 to 10 micrometers. In order to make the concave-convex structure 3 more obvious on the side of the second inorganic layer 2 away from the first inorganic layer 1, the thickness of the first inorganic layer 1 may be larger than that of the second inorganic layer 2.

Above-mentioned scheme, through set up first inorganic layer 1 below second inorganic layer 2, and first inorganic layer 1 comprises a plurality of archs 6 that the interval set up, make one side that second inorganic layer 2 deviates from first inorganic layer 1 form concave-convex structure 3, this concave-convex structure 3 is equivalent to and carries out roughening treatment to second inorganic layer 2, the levelling performance of the organic solution that forms organic layer 4 is relevant with second inorganic layer 2 surface structure, second inorganic layer 2 surface is coarse, then the levelling performance of organic solution is just high, higher levelling performance makes organic solution can fill whole second inorganic layer 2, avoided because of the deletion of second inorganic layer 2 partial region organic solution, the display luminance inequality (MURA) that causes, and the poor problem of later stage reliability.

As an implementation manner, in order to ensure the leveling property of the organic solution, the plurality of protrusions 6 are uniformly arranged, so that the concave-convex structures 3 are also uniformly arranged. For example, but not limited to, a plurality of protrusions 6 are arranged in a matrix.

As an implementable manner, the projection 6 is at least any one of a rectangular projection 6, a regular polygonal projection 6, a triangular projection 6, and a cross-shaped projection 6. In the same package structure, one kind of the bump 6 structure may be adopted, or two or more kinds of the bump 6 structures may be adopted. As shown in fig. 2 and 3, a rectangular projection 6 is used in this example. The arrangement density of the rectangular protrusions 6 can be different, and the included angle between the edge of the rectangular protrusion 6 and the edge of the second inorganic layer can also be different, for example, a certain included angle is formed between the edge of the rectangular protrusion 6 and the edge of the second inorganic layer in fig. 2, the size of the included angle can be determined according to actual conditions, and for example, in fig. 3, the edge of the rectangular protrusion 6 is parallel to the edge of the second inorganic layer. In other examples, a regular polygonal protrusion 6, a triangular protrusion 6, or a cross-shaped protrusion 6 may also be employed, as shown in fig. 4. Or a part of the area is provided with rectangular bulges 6, the other part of the area is provided with regular polygonal bulges 6, and the other part is provided with cross-shaped bulges 6.

As an implementation manner, in order to ensure the leveling property of the organic solution, the arrangement density of the protrusions 6 is 3% to 30%. The arrangement density here can be understood as a ratio of the plurality of projections 6 to the area of the second inorganic layer 2.

As an implementation manner, the material of the first inorganic layer 1 and the second inorganic layer 2 is at least any one of SiNx, siOx, siON, and AlOx. In general, the materials of the first inorganic layer 1 and the second inorganic layer 2 may be the same or different. The first inorganic layer 1 and the second inorganic layer 2 are preferably of a single-layer structure.

As an implementable manner, the material of the organic layer 4 is at least any one of acrylic acid, polyacrylate, polystyrene.

In a second aspect, as shown in fig. 5, the present invention provides a display panel, which includes a display substrate 7, wherein the display substrate 7 is, for example, but not limited to, an OLED display substrate. The display substrate 7 comprises a substrate, a thin film transistor layer and a functional layer which are sequentially stacked, wherein the functional layer comprises a first electrode layer, a pixel definition layer, a light emitting layer and a second electrode layer; the packaging structure is arranged on the second electrode layer and is used for packaging the functional layer, in other words, the packaging layer is used for packaging each light-emitting device in the light-emitting layer so as to enable each light-emitting device to be isolated from water and oxygen.

In the display substrate 7, the second electrode layer is directly arranged on the pixel defining layer, so that the arrangement of the shelf cushion layer on the pixel defining layer is eliminated, and the first inorganic layer 1 is used for replacing the shelf cushion layer, so that the concave-convex structure 3 is formed on one side of the second inorganic layer 2, which is far away from the first inorganic layer 1, or the arrangement density of the shelf cushions in the shelf cushion layer is reduced. For example, the display substrate 7 includes a substrate, a thin film transistor layer formed on the substrate, a planarization layer formed on the thin film transistor layer, a first electrode layer formed on the planarization layer, the first electrode layer serving as a cathode, a pixel defining layer formed on the first electrode layer, a light emitting device formed in an opening of the pixel defining layer, a second electrode layer formed on the pixel defining layer, the second electrode layer serving as an anode, and typically an ito layer. The first inorganic layer 1, the second inorganic layer 2, the organic layer 4, and the third inorganic layer 5 of the above-described package structure are sequentially formed on the second electrode layer.

In addition to the effect of the above-mentioned package structure, the display substrate 7 has the advantage that the first inorganic layer 1 is formed on the display substrate 7, which replaces the shelf cushion layer in the existing OLED display substrate, thereby avoiding the problem that the organic shelf cushion layer in the shelf cushion layer is scratched by the components such as the mask in the process of preparing the light emitting device. In addition, the display substrate 7 may also have a shelf cushion layer, but since the first inorganic layer 1 in the package structure enables the side of the second inorganic layer 2 away from the first inorganic layer 1 to form the concave-convex structure 3, and the shelf cushion layer is not needed to form the concave-convex structure 3 on the side of the second inorganic layer 2 away from the first inorganic layer 1, the shelf cushion layer is mainly used for supporting the mask plate in the evaporation process of the light emitting device, so that the density of the organic shelf cushion in the shelf cushion layer can be reduced, and the probability of being scratched by the mask plate is also reduced along with the reduction of the density of the organic shelf cushion.

In a third aspect, the present invention provides a display device, including the display panel.

Examples of the display device include, but are not limited to, any products or components having a display function such as a desktop computer, a tablet computer, a notebook computer, a mobile phone, a PDA (Personal Digital Assistant), a GPS (Global Positioning System), a vehicle-mounted display, a projection display, a video camera, a Digital camera, an electronic watch, a calculator, an electronic instrument, a meter, a liquid crystal panel, electronic paper, a television, a display, a Digital photo frame, and a navigator, and products or components having a display function such as a public display and a pseudo-display can be applied.

In a fourth aspect, as shown in fig. 6, the present invention provides a method for manufacturing the display panel, including:

s1: sequentially forming a thin film transistor layer and a functional layer on a substrate, wherein the functional layer comprises a first electrode layer, a pixel definition layer, a light emitting layer and a second electrode layer;

the thin-film transistor layer and the functional layer sequentially formed here may be formed by directly forming the functional layer on the thin-film transistor layer, or may be formed by further forming other layer structures between the thin-film transistor layer and the functional layer, such as, but not limited to, a planarization layer.

The existing preparation process of the display panel is as follows: the method includes the steps of forming a thin film transistor layer on a substrate, forming a planarization layer on the thin film transistor layer, forming a first electrode layer on the planarization layer, forming a pixel definition layer on the first electrode layer, forming a shelf layer on the pixel definition layer, forming a light emitting device in an opening of the pixel definition layer, and forming a second electrode layer on the pixel definition layer. Generally, the underlying layer is an organic layer, which is formed before the light emitting device, and when the light emitting device is formed by evaporation, the underlying layer is easily scratched by a member such as a mask.

In the present application, the second electrode layer is formed on the pixel defining layer, and the rest layer is not formed, but instead, the first inorganic layer 1 is formed on the second electrode layer.

Specifically, the display substrate 7 may be, but is not limited to, an OLED display substrate, and is formed by a process including forming a thin-film transistor layer on a substrate, forming a planarization layer on the thin-film transistor layer, forming a first electrode layer on the planarization layer, forming a pixel defining layer on the first electrode layer, forming light emitting devices in openings of the pixel defining layer, each of which may be collectively referred to as a light emitting layer, and forming a second electrode layer on the pixel defining layer. The light emitting device may include, for example, but not limited to, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer.

S2: forming a first inorganic layer 1 on the second electrode layer, the first inorganic layer 1 including a plurality of protrusions 6 disposed at intervals;

an inorganic thin film may be formed by chemical vapor deposition, and the inorganic thin film may be patterned to form the first inorganic layer 1 having a plurality of protrusions 6 disposed at intervals.

S3: forming a second inorganic layer 2 on the first inorganic layer 1, wherein the plurality of protrusions 6 are used for forming a concave-convex structure 3 on the side, away from the first inorganic layer 1, of the second inorganic layer 2;

an inorganic thin film may be formed on the first inorganic layer 1 by chemical vapor deposition, and the inorganic thin film serves as the second inorganic layer 2.

S4: forming an organic layer 4 on the second inorganic layer 2;

an organic solution is coated on the second inorganic layer 2 and dried to form an organic layer 4.

S5: a third inorganic layer 5 is formed on the organic layer 4.

An inorganic film is formed on the organic layer 4 by chemical vapor deposition, and the inorganic film is used as a third inorganic layer 5.

It will be understood that any orientation or positional relationship indicated above with respect to the terms "central," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc., is based on the orientation or positional relationship shown in the drawings and is for convenience in describing and simplifying the invention, and does not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and is therefore not to be considered limiting of the invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by those skilled in the art that the scope of the invention herein disclosed is not limited to the particular combination of features described above, but also encompasses other arrangements formed by any combination of the above features or their equivalents without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims (9)

1. An encapsulation structure comprises a first area corresponding to a display area of a display panel and a second area corresponding to a non-display area of the display panel; the organic light-emitting diode is characterized by comprising a first inorganic layer, a second inorganic layer, an organic layer and a third inorganic layer which are sequentially stacked;

the first inorganic layer comprises a plurality of bulges which are arranged at intervals, and the bulges are used for enabling one side of the second inorganic layer, which is far away from the first inorganic layer, to form a concave-convex structure;

the plurality of protrusions are distributed at least in the first region in a discrete manner, so that the organic solution forming the organic layer spreads over the entire second inorganic layer.

2. The package structure of claim 1, wherein the plurality of bumps are uniformly arranged.

3. The package structure according to claim 1, wherein the protrusion is at least any one of a regular polygonal protrusion, a triangular protrusion, and a cross-shaped protrusion.

4. The package structure according to claim 1, wherein the arrangement density of the bumps is 3% to 30%.

5. The package structure according to any one of claims 1 to 4, wherein the material of the first inorganic layer and the second inorganic layer is at least any one of SiNx, siOx, siON, alOx.

6. The encapsulation structure according to any one of claims 1 to 4, wherein the material of the organic layer is at least any one of acrylic acid, polyacrylate, polystyrene.

7. A display panel comprises a display substrate, and is characterized in that the display substrate comprises a substrate, a thin film transistor layer and a functional layer which are sequentially stacked, wherein the functional layer comprises a first electrode layer, a pixel definition layer, a light emitting layer and a second electrode layer;

further comprising an encapsulation structure according to any of claims 1 to 6, said encapsulation structure being arranged on said second electrode layer for encapsulating said functional layer.

8. A display device characterized by comprising the display panel according to claim 7.

9. A method for manufacturing a display panel according to claim 7, comprising:

sequentially forming a thin film transistor layer and a functional layer on a substrate, wherein the functional layer comprises a first electrode layer, a pixel definition layer, a light emitting layer and a second electrode layer;

forming a first inorganic layer on the second electrode layer, wherein the first inorganic layer comprises a plurality of bulges arranged at intervals;

forming a second inorganic layer on the first inorganic layer, wherein the plurality of protrusions are used for enabling one side of the second inorganic layer, which is far away from the first inorganic layer, to form a concave-convex structure;

forming an organic layer on the second inorganic layer;

a third inorganic layer is formed on the organic layer.

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