WO2020056809A1

WO2020056809A1 - Woled back plate and preparation method therefor

Info

Publication number: WO2020056809A1
Application number: PCT/CN2018/109625
Authority: WO
Inventors: 唐甲; 任章淳
Original assignee: 深圳市华星光电半导体显示技术有限公司
Priority date: 2018-09-21
Filing date: 2018-10-10
Publication date: 2020-03-26
Also published as: CN109346502A

Abstract

Provided in the present application are a WOLED back plate and a preparation method therefor. The WOLED back plate comprises: a bottom-layer thin-film transistor layer, a color film, a flat layer and an anode that are sequentially arranged on a substrate, wherein the color film comprises sub-color film units that are arranged at intervals, the flat layer is provided with a groove at a position corresponding to an interval between the two adjacent sub-color film units, and the anode is arranged corresponding to the sub-color film units; and a pixel definition layer, wherein same is arranged at a position, corresponding to the groove, on the flat layer, and the pixel definition layer is made of a light-absorbing material.

Description

WOLED back plate and preparation method thereof

Technical field

The present application relates to the field of display technology, and in particular, to a WOLED backplane and a method for preparing the same.

Background technique

With the continuous improvement of the backplane resolution, the number of pixels and the spacing between sub-pixels continue to decrease. For bottom emission WOLED (COA) light, light needs to pass through the flat layer and R / G / B color film. The flat layer is generally a highly penetrating organic material, and the multi-directionality of light propagation often causes pixels that do not need to emit light to emit light due to adjacent pixels emitting light, which appears as light leakage.

Therefore, the prior art has defects and urgently needs improvement.

technical problem

The present application provides a WOLED backplane and a method for manufacturing the same, which can solve the problem of light leakage caused by pixels.

Technical solutions

To solve the above problems, the technical solutions provided in this application are as follows:

The present application provides a method for preparing a WOLED backplane. The method includes the following steps:

Step S10, providing a substrate having a bottom thin film transistor layer formed thereon, and forming a patterned color film on the bottom thin film transistor layer, the color film including sub color film units corresponding to the sub pixels in a spaced distribution;

Step S20: forming a flat layer on the color film, and patterning the flat layer to form a groove corresponding to a spaced position between two adjacent sub color film units;

Step S30: forming a patterned anode corresponding to the sub-color film unit on the flat layer;

In step S40, a patterned pixel definition layer is formed at the position of the groove, and the pixel definition layer defines a pixel area, wherein a material of the pixel definition layer is a light-absorbing material.

In the method for preparing a WOLED backplane of the present application, the sub-color film unit includes a red color film unit, a green color film unit, and a blue color film unit.

In the method for manufacturing a WOLED backplane of the present application, the flat layer includes a completely reserved area and a partially reserved area, and the flat layer corresponding to the completely reserved area is completely completed in the patterning process in step S20. Occlusion, and half-exposing the flat layer corresponding to the partially reserved area.

In the method for preparing a WOLED backplane of the present application, the completely reserved area of the flat layer corresponds to the sub color film unit, and the partially reserved area corresponds to a space position between two adjacent sub color film units. .

In the method for preparing a WOLED back sheet of the present application, after the step S40, the method further includes the following steps:

Step S50: forming an organic light emitting layer in the pixel region;

In step S60, a cathode layer is formed on the organic light emitting layer.

To solve the above problems, this application also provides a WOLED backplane, including:

Substrate

A bottom thin film transistor layer is prepared on the substrate;

A color film prepared on the underlying thin film transistor layer, the color film including sub-color film units spaced apart from each other; and

A flat layer prepared on the color film and provided with a groove at a position corresponding to an interval between two adjacent color film units;

An anode, which is prepared on the flat layer corresponding to the sub-color film unit array, and the anode is located at a position between the flat layer corresponding to two adjacent grooves, and the grooves are exposed;

A pixel definition layer, prepared on the flat layer corresponding to the position of the groove, and defining a pixel area;

The material of the pixel definition layer is a light absorbing material.

In the WOLED backplane of the present application, the groove and the sub-color film unit are separated by the flat layer.

In the WOLED backplane of the present application, the groove is a grid-like structure surrounding the sub-color film unit.

In the WOLED backplane of the present application, the pixel definition layer includes an insertion portion and a spacer portion, the insertion portion is inserted into the groove, the spacer portion protrudes from the flat layer and two adjacent Pixel areas are spaced apart.

In the WOLED back sheet of the present application, the spacer portion extends to an edge portion of the anode.

In the WOLED backplane of the present application, the insertion portion and the spacer portion are designed in one piece.

Substrate

A bottom thin film transistor layer is prepared on the substrate;

The anode is prepared on the flat layer corresponding to the sub-color film unit array;

The material of the pixel definition layer is a light absorbing material.

Beneficial effect

The beneficial effect of the present application is that, compared with the existing WOLED backplane, the WOLED backplane and the preparation method thereof provided by the present application are provided with grooves on a flat layer corresponding to the space between adjacent two color film units And inserting the insertion portion of the pixel definition layer of the light absorbing material in the groove, so that the inside of the flat layer provided on the color film separates the different color film units by the light absorbing material, thereby avoiding the occurrence of different pixels Problems with light leakage or color mixing. In addition, the insertion portion is obtained by designing the pixel definition layer, so there is no need to increase the manufacturing process of the insertion portion.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly explain the embodiments or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for application. For some embodiments, for those skilled in the art, other drawings can be obtained based on these drawings without paying creative labor.

FIG. 1 is a flowchart of a method for preparing a WOLED backplane according to an embodiment of the present application; FIG.

2A ~ 2D are schematic diagrams of a manufacturing process of a WOLED back sheet provided in an embodiment of the present application;

FIG. 3 is a schematic structural diagram of a WOLED backplane provided by an embodiment of the present application.

Embodiments of the invention

The following descriptions of the embodiments are with reference to the attached drawings to illustrate specific embodiments that can be implemented by the present application. The directional terms mentioned in this application, such as [up], [down], [front], [rear], [left], [right], [in], [out], [side], etc., are for reference only. The direction of the attached schema. Therefore, the directional terms used are used to explain and understand this application, not to limit this application. In the figure, similarly structured units are denoted by the same reference numerals.

This application is directed to the existing WOLED backplane, which has the technical problem of light leakage or color mixing between adjacent pixels. This embodiment can solve this defect.

As shown in FIG. 1, it is a flowchart of a method for preparing a WOLED backplane provided by an embodiment of the present application. With reference to Figs. 2A to 2D, a schematic diagram of a manufacturing process of a WOLED backplane provided by an embodiment of the present application is shown. The method includes the following steps:

In step S10, a substrate on which an underlying thin film transistor layer is formed is provided. A patterned color film is formed on the underlying thin film transistor layer, and the color film includes sub-color film units corresponding to sub-pixels spaced apart from each other.

Specifically, as shown in FIG. 2A, an underlying thin film transistor layer 202 is formed on a substrate 201; and a patterned color film 203 is formed on the underlying thin film transistor layer 202. The color film 203 includes a sub color film unit 203A, and a gap 203B exists between two adjacent sub color film units 203A. The sub-color film unit 203A includes, but is not limited to, a red sub-color film unit, a green sub-color film unit, and a blue sub-color film unit.

In step S20, a flat layer is formed on the color film, and the flat layer is patterned to form a groove corresponding to a spaced position between two adjacent sub color film units.

2B, a flat layer 204 is formed on the color film 203, and the flat layer 204 is patterned. The flat layer 204 includes a fully reserved area 204B and a partially reserved area 204C. The completely reserved area 204B corresponds to the sub-color film unit 203A, and the partially reserved area 204C corresponds to the position 203B between two adjacent sub-color film units 203A. In the patterning process, the flat layer 204 corresponding to the completely reserved area 204B is completely blocked, and the flat layer 204 corresponding to the partially reserved area 204C is half-exposed. After patterning, a groove 204A corresponding to the position of the space 203B is formed.

In one embodiment, the groove 204A may be a grid-like structure surrounding the sub-color film unit 203A.

In step S30, a patterned anode corresponding to the sub-color film unit is formed on the flat layer.

As shown in FIG. 2C, an anode metal layer is prepared on the flat layer 204. After the anode metal layer is patterned, a plurality of anodes 205 corresponding to the sub-color film unit 203A are formed, and the anodes 205 expose the grooves. 204A.

As shown in FIG. 2D, a patterned pixel definition layer 206 is formed on the anode 205. The pixel definition layer 206 uses a black light-absorbing material and is located at the position of the groove 204A. The pixel definition layer 206 defines Pixel area 207.

After the step S40, the method further includes the following steps:

Step S50: forming an organic light emitting layer in the pixel region;

In step S60, a cathode layer is formed on the organic light emitting layer.

The organic light-emitting material forming the organic light-emitting layer may be an evaporation material or a printing light-emitting material. The corresponding pixel definition layers 206 are conventional non-hydrophobic materials and hydrophobic materials, respectively.

In this embodiment, the pixel definition layer can both define the pixel area and also serve as a light-shielding column between two adjacent sub-color film units, so that the inside of the flat layer provided on the color film is light-absorbing material. Different sub-color film units are spaced apart, thereby avoiding the problem of light leakage or color mixing between different pixels.

This application also provides a WOLED backplane. As shown in FIG. 3, the WOLED backplane includes: a substrate 301; an underlying thin film transistor layer 302 prepared on the substrate 301; and a color film 303 prepared on the underlying film. On the transistor layer 302, the color film 303 includes sub-color film units 303A spaced apart from each other; a flat layer 304 is prepared on the color film 303 and corresponds to an interval between two adjacent sub-color film units 303A. A groove 304A is provided at the position of 303B; an anode 305 is prepared on the flat layer 304 corresponding to the sub-color film unit 303A; the anode 305 is located between the two flat grooves 304A corresponding to the two adjacent grooves 304A Part of the groove so that the groove 304A is exposed; a patterned pixel definition layer 306 is prepared on the flat layer 304 corresponding to the position of the groove 304A and defines a pixel area 307; wherein the pixel definition layer The material of 306 is a light absorbing material; an organic light emitting layer can be prepared in the pixel region 307, and a cathode layer is prepared on the organic light emitting layer.

The groove 304A and the sub-color film unit 303A are separated by the flat layer 304. The depth and size of the groove 304A can be designed according to actual needs. The half-tone mask process can also be used, or the ordinary mask process can be used.

The pixel definition layer 306 includes an insertion portion 306A and a spacer portion 306B. The insertion portion 306A is inserted into the groove 304A. The spacer portion 306B protrudes from the flat layer 304 and connects two adjacent pixel regions. 307 are spaced apart. The inserting portion 306A and the spacer portion 306B are integrally designed, and a portion of the spacer portion 306B that is in contact with the anode 305 extends to an edge portion of the anode 305. In this way, a gap is formed between the pixel defining layer 306 and the anode 305 to prevent light leakage. The WOLED backplane may further include other conventional film layers, such as a thin film encapsulation layer, etc., and details are not described herein again.

In an embodiment of the present application, the sub-color film unit 303A includes, but is not limited to, a red sub-color film unit, a green sub-color film unit, and a blue sub-color film unit.

The material of the pixel definition layer 306 in the present application is a material having extremely low light transmittance and can play a role of blocking light, which is not specifically limited.

In the embodiment of the present application, as shown by an arrow in the figure, light is transmitted through the anode 305 and the flat layer 304 to the sub-color film unit 303A. Since the flat layer 304 that emits light at the bottom is generally high Penetrating organic materials, and due to the multi-directional nature of light propagation, pixels that do not need to emit light often emit light due to the emission of adjacent pixels, showing light leakage or color mixing. Through the design of the pixel definition layer 306 in this application, the insertion portion 306A of the pixel definition layer 306 is located in the flat layer 304 and is located between two adjacent sub-color film units 303A. The light entering the flat layer 304 and directed to the adjacent sub-color film unit 303A is effectively blocked, so as to avoid light leakage or color mixing between adjacent pixels.

In summary, although the present application has been disclosed above with preferred embodiments, the above preferred embodiments are not intended to limit the present application. Those skilled in the art can make various modifications without departing from the spirit and scope of the present application. This modification and retouching, therefore, the scope of protection of this application shall be based on the scope defined by the claims.

Claims

A method for preparing a WOLED backplane, wherein the method includes the following steps:

Step S10, providing a substrate having a bottom thin film transistor layer formed thereon, and forming a patterned color film on the bottom thin film transistor layer, the color film including sub color film units corresponding to the sub pixels in a spaced distribution;

Step S20: forming a flat layer on the color film, and patterning the flat layer to form a groove corresponding to a spaced position between two adjacent sub color film units;

Step S30: forming a patterned anode corresponding to the sub-color film unit on the flat layer;

In step S40, a patterned pixel definition layer is formed at the position of the groove, and the pixel definition layer defines a pixel area, wherein a material of the pixel definition layer is a light-absorbing material.
The method according to claim 1, wherein the sub-color film unit comprises a red color film unit, a green color film unit, and a blue color film unit.
The manufacturing method according to claim 1, wherein the flat layer includes a fully reserved area and a partially reserved area, and the flat layer corresponding to the fully reserved area is completely completed in the patterning process in step S20. Occlusion, and half-exposing the flat layer corresponding to the partially reserved area.
The manufacturing method according to claim 3, wherein the completely reserved area of the flat layer corresponds to the sub-color film unit, and the partial reserved area corresponds to a space position between two adjacent sub-color film units. .
The method according to claim 1, wherein after the step S40, the method further comprises the following steps:

Step S50: forming an organic light emitting layer in the pixel region;

In step S60, a cathode layer is formed on the organic light emitting layer.
A WOLED backplane includes:

Substrate

A bottom thin film transistor layer is prepared on the substrate;

A color film prepared on the underlying thin film transistor layer, the color film including sub-color film units spaced apart from each other; and

A flat layer prepared on the color film and provided with a groove at a position corresponding to an interval between two adjacent color film units;

An anode, which is prepared on the flat layer corresponding to the sub-color film unit array, and the anode is located at a position between the flat layer corresponding to two adjacent grooves, and the grooves are exposed;

A pixel definition layer, prepared on the flat layer corresponding to the position of the groove, and defining a pixel area;

The material of the pixel definition layer is a light absorbing material.
The WOLED backplane according to claim 6, wherein the groove and the sub-color film unit are separated by the flat layer.
The WOLED backplane according to claim 6, wherein the groove is a grid-like structure surrounding the sub-color film unit.
The WOLED backplane according to claim 6, wherein the pixel defining layer includes an insertion portion and a spacer portion, the insertion portion is inserted into the groove, and the spacer portion projects from the flat layer and forms The two adjacent pixel regions are spaced apart.
The WOLED backplane according to claim 9, wherein the spacer portion extends to an edge portion of the anode.
The WOLED backplane according to claim 9, wherein the inserting portion and the spacer portion are integrally designed.
A WOLED backplane includes:

Substrate

A bottom thin film transistor layer is prepared on the substrate;

A color film prepared on the underlying thin film transistor layer, the color film including sub-color film units spaced apart from each other; and

A flat layer prepared on the color film and provided with a groove at a position corresponding to an interval between two adjacent color film units;

The anode is prepared on the flat layer corresponding to the sub-color film unit array;

A pixel definition layer, prepared on the flat layer corresponding to the position of the groove, and defining a pixel area;

The material of the pixel definition layer is a light absorbing material.
The WOLED backplane according to claim 12, wherein the groove and the sub-color film unit are separated by the flat layer.
The WOLED backplane according to claim 12, wherein the groove is a grid-like structure surrounding the sub-color film unit.
The WOLED backplane according to claim 12, wherein the pixel defining layer includes an insertion portion and a spacer portion, the insertion portion is inserted into the groove, and the spacer portion protrudes from the flat layer and forms a phase. The two adjacent pixel regions are spaced apart.
The WOLED backplane according to claim 15, wherein the spacer portion extends to an edge portion of the anode.
The WOLED backplane according to claim 15, wherein the inserting portion and the spacer portion are integrally designed.