CN108987431B

CN108987431B - Pixel structure and manufacturing method thereof

Info

Publication number: CN108987431B
Application number: CN201711396055.9A
Authority: CN
Inventors: 陈亚文
Original assignee: Guangdong Juhua Printing Display Technology Co Ltd
Current assignee: Guangdong Juhua Printing Display Technology Co Ltd
Priority date: 2017-12-21
Filing date: 2017-12-21
Publication date: 2021-07-20
Anticipated expiration: 2037-12-21
Also published as: CN108987431A

Abstract

The invention relates to a pixel structure and a manufacturing method thereof. The pixel structure includes: a substrate; a pixel defining layer laminated over the substrate; the pixel defining layer comprises a first pixel bank, a second pixel bank and a plurality of pixel cavities which are formed by the first pixel bank and the second pixel bank and correspond to sub-pixels one by one; the pixel cavities on two sides of the first pixel bank are used for arranging sub-pixels with the same color, and the pixel cavities on two sides of the second pixel bank are used for arranging sub-pixels with different colors; the surface of the first pixel bank is provided with a first lyophilic pixel defining layer. The pixel structure can realize high-resolution printing, avoid leakage current among functional layers and optimize the display effect.

Description

Pixel structure and manufacturing method thereof

Technical Field

The invention relates to the technical field of display, in particular to a pixel structure and a manufacturing method thereof.

Background

Organic electroluminescent diodes (OLEDs) and quantum dot light emitting diodes (QLEDs) are two major directions of research in display devices today. The Organic Light Emitting Diode (OLED) has the advantages of self luminescence, fast reaction, wide visual angle, high brightness, lightness, thinness and the like, and the quantum dot light emitting diode (QLED) has the advantages of high light color purity, high light emitting quantum efficiency, easy adjustment of light emitting color, long service life and the like. The solution processing method for manufacturing the OLED and the QLED display is an important direction for the development of future display technology due to the advantages of low cost, high productivity, easy realization of large size and the like. Among them, printing technology is considered to be the most effective way to achieve low cost and large area full color display of OLEDs as well as QLEDs.

In the printing process, sub-pixels with the same color of adjacent pixels are gathered together through optimization of a pixel arrangement structure, and then the deposition area of ink can be enlarged through optimization of a pixel bank structure, so that the preparation of a high-resolution display is realized. However, with this structure, the functional layers of the sub-pixels in the same ink deposition region are all integrated, which easily causes a lateral leakage current, and further affects the display contrast and display effect of the entire display panel.

Disclosure of Invention

Based on this, it is necessary to provide a pixel structure. The pixel structure can realize high-resolution printing, avoid leakage current among functional layers and optimize the display effect.

A pixel structure, comprising:

a substrate;

a pixel defining layer laminated over the substrate; the pixel defining layer comprises a first pixel bank, a second pixel bank and a plurality of pixel cavities which are formed by the first pixel bank and the second pixel bank and correspond to sub-pixels one by one;

the pixel cavities on two sides of the first pixel bank are used for arranging sub-pixels with the same color, and the pixel cavities on two sides of the second pixel bank are used for arranging sub-pixels with different colors;

the surface of the first pixel bank is provided with a first lyophilic pixel defining layer.

In one embodiment, the surface of the second pixel bank in contact with the functional layer of the sub-pixel is provided with a second lyophilic pixel defining layer. Therefore, the functional layer ink can be ensured to spread on the electrode layer, and the short circuit phenomenon caused by retraction when the ink is dried is prevented.

In one embodiment, the second pixel bank is made of a lyophobic material. The second pixel bank is made of lyophobic materials, so that the ink can be prevented from overflowing to other adjacent ink deposition areas during printing to cause color mixing.

In one embodiment, the thickness of the second pixel bank is 800-; the thickness of the functional layer of the sub-pixel is 100-500 nm. The thicknesses of the second pixel bank and the functional layer (namely the height covered by the second lyophilic pixel defining layer on the second pixel bank) are reasonably set, so that ink in an ink deposition area can not overflow to other adjacent ink deposition areas in the printing process while the ink in the functional layer is well spread.

In one embodiment, the first lyophilic pixel defining layer and/or the second lyophilic pixel defining layer has a thickness of 50-200 nm.

In one embodiment, the thickness of the first pixel bank is 800-.

In one embodiment, the first pixel bank is composed of a lyophobic material.

In the pixel structure of the present invention, the substrate may be a glass substrate or a flexible substrate, and may have thereon a TFT driving array for driving a light emitting device. The electrode is arranged on the substrate and can be a conductive film layer. When the display panel is a bottom emission type panel, the conductive film layer is a transparent conductive film layer, such as a conductive metal oxide of ITO, IZO, or the like, or a high-conductivity organic conductive material of graphene, a conductive polymer, or the like; when the display panel is a top emission type panel, the conductive film layer is a reflective conductive film layer, such as a highly conductive metal film of Al, Ag, or an alloy thereof.

The invention also provides a manufacturing method of the pixel structure, which comprises the following steps:

obtaining the substrate;

depositing the pixel defining layer on the substrate; the pixel defining layer comprises a first pixel bank, a second pixel bank and a plurality of pixel cavities which are formed by the first pixel bank and the second pixel bank and correspond to sub-pixels one by one; the pixel cavities on two sides of the first pixel bank are used for arranging sub-pixels with the same color, and the pixel cavities on two sides of the second pixel bank are used for arranging sub-pixels with different colors;

and forming the first lyophilic pixel defining layer on the surface of the first pixel bank.

In one embodiment, the method further comprises the following steps: and forming the second lyophilic pixel defining layer on the surface of the second pixel bank, which is in contact with the functional layer of the sub-pixel.

The invention also provides a display panel which comprises the pixel structure or the pixel structure manufactured by the manufacturing method.

The invention also provides a display device comprising the display panel.

Compared with the prior art, the invention has the following beneficial effects:

according to the pixel structure, the first lyophilic pixel defining layer is arranged on the surface of the first pixel bank, ink in the pixel cavity with the same pixel color can be spread by using lyophilic property without reducing the height of the pixel defining bank, the deposition area of the ink is enlarged, the high resolution of the pixel structure is ensured, meanwhile, the first pixel bank has the same height as the second pixel bank, the phenomenon that the organic functional layer generates transverse leakage current in the area due to the fact that the height of the pixel defining layer in the ink deposition area is small is avoided, and the display effect is optimized.

Furthermore, a second lyophilic pixel defining layer is arranged on the surface, in contact with the functional layer of the sub-pixel, of the second pixel bank, so that spreading of ink of the functional layer on the electrode layer can be guaranteed, and the phenomenon of short circuit caused by retraction when the ink is dry is prevented.

Drawings

FIG. 1 is a schematic diagram of a pixel structure according to an embodiment of the invention;

FIG. 2 is a top view of the pixel structure shown in FIG. 1;

FIG. 3 is a flow chart of a process for fabricating the pixel structure shown in FIG. 1;

fig. 4 is a schematic structural diagram of step S1 in the method for manufacturing the pixel structure shown in fig. 1;

fig. 5 is a schematic structural diagram of step S3 in the method for manufacturing the pixel structure shown in fig. 1.

Detailed Description

The following describes the pixel structure and the manufacturing method thereof in detail with reference to specific embodiments.

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Examples

A pixel structure of the present embodiment, as shown in fig. 1 and 2, includes:

a substrate 100;

a pixel defining layer 200 laminated on the substrate 100; the pixel defining layer 200 comprises a first pixel bank300 and a second pixel bank400, and a plurality of pixel cavities which are surrounded by the first pixel bank300 and the second pixel bank400 and correspond to sub-pixels one by one; the pixel cavities on two sides of the first pixel bank300 are used for arranging sub-pixels with the same color, and the pixel cavities on two sides of the second pixel bank400 are used for arranging sub-pixels with different colors;

the surface of the first pixel bank300 is provided with a first lyophilic pixel defining layer 202. It is understood that, in other embodiments, the entire first pixel bank300 may be made of lyophilic material, so that the surface thereof has lyophilic property.

According to the pixel structure, the first lyophilic pixel defining layer 202 is arranged on the surface of the first pixel bank300, the spreading of ink in a pixel cavity with the same pixel color can be realized by utilizing lyophilic property without reducing the height of the pixel defining layer at the position, the deposition area of the ink is enlarged, the high resolution of the pixel structure is ensured, meanwhile, the first pixel bank300 has the same height as the second pixel bank400, the phenomenon that the organic functional layer generates transverse leakage current in the area due to the fact that the height of the pixel defining layer in the ink deposition area is small is avoided, and the display effect is optimized.

Further, a second lyophilic pixel defining layer 203 is disposed on a surface of the second pixel bank400 in contact with the functional layer of the sub-pixel. Therefore, the functional layer ink can be ensured to spread on the electrode layer, and the short circuit phenomenon caused by retraction when the ink is dried is prevented.

In this embodiment, the second pixel bank400 is made of a lyophobic material, and is combined with the second lyophilic pixel defining layer 203 to form a partially hydrophilic structure, so that the ink can be prevented from overflowing to other adjacent ink deposition areas during printing to cause color mixing. Specifically, the thickness of the second pixel bank400 is 800-; the thickness of the functional layer of the sub-pixel (i.e. the vertical height of the second lyophilic pixel definition layer 203 covering on the second pixel bank 400) is 100-500 nm. The ink in the ink deposition area can not overflow to other adjacent ink deposition areas in the printing process while the ink in the functional layer is well spread.

The thickness of the first lyophilic pixel defining layer 202 and the second lyophilic pixel defining layer 203 may be set to 50-200nm, thereby enabling a better functional layer ink spreading effect.

In addition, in order to facilitate the fabrication of the first pixel bank300 while forming the second pixel bank400, and to simplify the fabrication process of the device, in this embodiment, the first pixel bank300 is also configured to be made of a lyophobic material.

The manufacturing process flow chart of the pixel structure is shown in fig. 3, and includes the following steps:

s1, providing a substrate 100 having a driving circuit and a patterned pixel electrode thereon, as shown in fig. 4;

s2, depositing a lyophobic material layer on the whole surface;

s3, patterning the lyophobic material layer through a yellow light process to form a first pixel bank300 and a second pixel bank 400; as shown in fig. 5;

s4, depositing a lyophilic material layer on the whole surface;

s5, patterning the lyophilic material layer by a yellow light process, forming a first lyophilic pixel defining layer 202 on the surface of the first pixel bank300, and forming a second lyophilic pixel defining layer 203 on the surface of the second pixel bank400 in contact with the functional layer of the sub-pixel, so as to expose the other lyophobic second pixel banks 400, thereby obtaining the pixel structure, as shown in fig. 1.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A pixel structure, comprising:

a substrate;

a pixel defining layer laminated over the substrate; the pixel defining layer comprises a first pixel bank, a second pixel bank and a plurality of pixel cavities which are formed by the first pixel bank and the second pixel bank and correspond to sub-pixels one by one; the first pixel bank has the same height as the second pixel bank;

the whole surface of the first pixel bank is provided with a first lyophilic pixel defining layer;

the thickness of the second pixel bank is 800-; the thickness of the functional layer of the sub-pixel is 100-500 nm.

2. The pixel structure of claim 1, wherein the first lyophilic pixel defining layer has a thickness of 50-200 nm.

3. The pixel structure according to claim 1, wherein a surface of the second pixel bank in contact with the functional layer of the sub-pixel is provided with a second lyophilic pixel definition layer.

4. The pixel structure according to claim 3, wherein the second pixel bank is composed of a lyophobic material.

5. The pixel structure of claim 3, wherein the second lyophilic pixel definition layer has a thickness of 50-200nm, or,

the first lyophilic pixel defining layer and the second lyophilic pixel defining layer have a thickness of 50-200 nm.

6. A method of fabricating a pixel structure according to any one of claims 3 to 5, comprising the steps of:

obtaining the substrate;

depositing the pixel defining layer on the substrate; the pixel defining layer comprises a first pixel bank, a second pixel bank and a plurality of pixel cavities which are formed by the first pixel bank and the second pixel bank and correspond to sub-pixels one by one; the pixel cavities on two sides of the first pixel bank are used for arranging sub-pixels with the same color, and the pixel cavities on two sides of the second pixel bank are used for arranging sub-pixels with different colors; the first pixel bank has the same height as the second pixel bank;

forming the first lyophilic pixel defining layer on the entire surface of the first pixel bank.

7. The method of claim 6, further comprising the steps of: and forming the second lyophilic pixel defining layer on the surface of the second pixel bank, which is in contact with the functional layer of the sub-pixel.

8. A display panel comprising the pixel structure according to any one of claims 1 to 5 or the pixel structure manufactured by the manufacturing method according to any one of claims 6 to 7.

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