WO2020118874A1

WO2020118874A1 - Method for preparing display

Info

Publication number: WO2020118874A1
Application number: PCT/CN2019/072834
Authority: WO
Inventors: 顾宇
Original assignee: 武汉华星光电半导体显示技术有限公司
Priority date: 2018-12-13
Filing date: 2019-01-23
Publication date: 2020-06-18
Also published as: CN109599507A

Abstract

A method for preparing a display, comprising the following steps: a pixel definition layer (2) preparation step, a through hole (21) setting step, a first functional layer (3) preparation step, a pixel organic layer (4) preparation step, a second functional layer (5) preparation step and an electrode layer (6) preparation step. The technical effect lies in that a high-pixel-density display can be prepared without using a precise mask plate, which saves on costs, and has a simple and easy manufacturing process. A vapor deposition sulfur layer is easier to operate than a precise mask plate, thereby greatly reducing cleaning and maintenance costs.

Description

Display preparation method

Technical field

The present invention relates to the field of displays, and in particular to a method for preparing displays.

Background technique

Organic light-emitting device (organic light-emitting device, OLED) due to its ability to actively emit light, can work at low temperatures, light-emitting response speed, wide viewing angle, high efficiency, can be made flexible display device, driving voltage and low energy consumption, etc. The advantages have attracted the attention of many display manufacturers around the world and are considered the next generation of display technology.

With the rapid development of new display technologies, OLED displays have been given more expectations, such as a wider color gamut, higher contrast, lower energy consumption, and higher resolution.

The traditional RGB sub-pixel arrangement is shown in Figures 1 and 2. The three sub-pixels of the red, green and blue primary colors are used for arrangement. Figure 1 shows the arrangement of the sub-pixels side by side, and Figure 2 shows the arrangement of the sub-pixels pentile. Compared with the side-by-side arrangement, the large material area reduces the difficulty of the process and reduces the cost, but the clarity will also be reduced.

In the current mainstream OLED production process, multiple sets of FMM (Fine-Metal-Mask, precision mask) are required to complete the preparation of full-color displays. The production, transportation, cleaning, and maintenance costs of FMM are relatively high. At the same time, the production method of high-resolution FMM is only mastered by a few manufacturers and has limited production capacity. Therefore, it is necessary to develop new high-resolution display manufacturing technology.

The technical difficulty of the existing high-PPI FMM is that in order to reduce the shadow effect of the mask, an ultra-thin mask is required. It is very difficult to make holes in such a thin metal sheet and ensure that the openings and the pixel area of the substrate can be accurately aligned even after the mask is opened.

technical problem

The purpose of the present invention is to solve the problem that the manufacturing, transportation, cleaning and maintenance of precision mask plates are relatively high in the existing OLED production process. Opening holes in ultra-thin mask plates and ensuring that the mask plates are still opened It can make technical problems such as the difficulty of accurately aligning the opening and the pixel area of the substrate.

Technical solution

The present invention provides a method for manufacturing a display, including the following steps: S1 pixel definition layer preparation step, providing a substrate on which a pixel definition layer is coated, including more than two pixel unit areas; S2 through hole setting Step, the pixel definition layer in each pixel unit area is provided with three through holes, namely a first through hole, a second through hole and a third through hole; S3 the first functional layer preparation step, on the pixel definition layer A first functional layer is evaporated; S4 pixel organic layer preparation step, three sub-pixel organic layers are prepared in sequence, corresponding to three through holes; S5 second functional layer preparation step, vapor deposition on the pixel functional layer A second functional layer; and an S6 electrode layer preparation step, an electrode layer is evaporated on the upper surface of the second functional layer.

Further, the pixel organic layer preparation step includes, in order: S41 a first sub-pixel organic layer preparation step to prepare a first sub-pixel organic layer; S42 a second sub-pixel organic layer preparation step to prepare a second sub-pixel organic layer; And S43 a third sub-pixel organic layer preparation step to prepare a third sub-pixel organic layer.

Further, the first sub-pixel organic layer preparation step includes: S411 first sulfur layer preparation step, using a mask to block the first through hole and its surrounding area, and steaming on the first functional layer The first sulfur layer is plated and the mask is removed; S412 the first pixel organic layer preparation step, a first pixel organic layer material is evaporated on the upper surface of the first functional layer to obtain a first pixel organic layer ; And S413 the first heating step, heating the substrate, so that the first sulfur layer is evaporated or sublimed, the first pixel organic layer above the first sulfur layer is stripped, and the remaining first pixel organic layer is the first A sub-pixel organic layer.

Further, the second sub-pixel organic layer preparation step includes: S421 second sulfur layer preparation step, using a mask to block the second through hole and its surrounding area, in the first sub-pixel organic layer And a second sulfur layer is vapor-deposited on the first functional layer to remove the mask plate; S422 second pixel organic layer preparation step, a second pixel organic layer is vapor-deposited on the upper surface of the first functional layer Material to obtain a second pixel organic layer; and S423 the second heating step, heating the substrate so that the second sulfur layer evaporates or sublimes, the second pixel organic layer above the second sulfur layer is peeled off, remaining The second pixel organic layer is the second sub-pixel organic layer.

Further, the step of preparing the third sub-pixel organic layer includes: a step of preparing a third sulfur layer of S431, a third mask is used to block the third through hole and its surrounding area, and the first sub-pixel organic layer and A third sulfur layer is vapor-deposited on the second sub-pixel organic layer to remove the mask; S432 third pixel organic layer preparation step, a third pixel organic layer is vapor-deposited on the upper surface of the first functional layer Layer material to obtain a third pixel organic layer; and a third heating step of S433, heating the substrate so that the third sulfur layer is evaporated or sublimed, and the third pixel organic layer above the third sulfur layer is stripped, The remaining third organic layer is the third sub-pixel organic layer.

Further, the first sub-pixel organic layer, the second sub-pixel organic layer and the third sub-pixel organic layer in the same pixel unit area are connected in sequence.

Further, the first sub-pixel organic layer, the second sub-pixel organic layer, and the third sub-pixel organic layer are one of a green organic layer, a blue organic layer, and a red organic layer and are different from each other.

Further, the first functional layer includes at least one of a hole injection layer and a hole transport layer.

Further, the second functional layer includes at least one of a hole blocking layer, an electron transport layer, and an electron injection layer.

Further, the electrode layer includes a light extraction layer.

Beneficial effect

The technical effect of the present invention is to replace the original precision masks with different sizes and shapes of through holes by ordinary masks with large through holes, without using precision masks, a high pixel density display can be prepared, and the manufacturing process is reduced The difficulty and cost savings. Taking advantage of sulfur's volatile and sublimable characteristics, the organic layer material above the sulfur layer covered area is stripped away, leaving the sub-pixel organic layer not covered by the sulfur layer, achieving the purpose of high pixel density display. Aperture ordinary mask is easier to operate than precision mask, and it greatly reduces cleaning and maintenance costs.

BRIEF DESCRIPTION

1 is an arrangement diagram of a conventional RGB sub-pixel in the prior art;

2 is an arrangement diagram of another conventional RGB sub-pixel in the prior art;

3 is a flowchart of a method for manufacturing a display according to an embodiment of the invention;

4 is a schematic structural diagram of a display after the step of setting a through hole according to an embodiment of the present invention;

5 is a schematic structural diagram of a display after the first functional layer preparation step according to an embodiment of the present invention;

6 is a flowchart of steps for preparing a pixel organic layer according to an embodiment of the invention;

7 is a flowchart of steps for preparing a first sub-pixel organic layer according to an embodiment of the invention;

8 is a schematic structural diagram of a display after the first sulfur layer preparation step according to an embodiment of the present invention;

9 is a schematic structural diagram of a display after a step of preparing a first pixel organic layer according to an embodiment of the present invention;

10 is a schematic structural diagram of a display during the first heating step according to an embodiment of the present invention;

11 is a schematic structural diagram of a display after the first heating step according to an embodiment of the present invention;

12 is a flowchart of steps for preparing a second sub-pixel organic layer according to an embodiment of the invention;

13 is a schematic structural diagram of a display after the second sulfur layer preparation step according to an embodiment of the present invention;

14 is a schematic diagram of the display structure after the step of preparing the second pixel organic layer according to the embodiment of the present invention;

15 is a schematic structural diagram of a display during a second heating step according to an embodiment of the present invention;

16 is a schematic structural diagram of a display after a second heating step according to an embodiment of the present invention;

17 is a flowchart of steps for preparing a third sub-pixel organic layer according to an embodiment of the present invention;

18 is a schematic structural diagram of a display after the third sulfur layer preparation step according to an embodiment of the present invention;

19 is a schematic structural diagram of a display after a step of preparing a third pixel organic layer according to an embodiment of the present invention;

20 is a schematic structural diagram of a display during a third heating step according to an embodiment of the present invention;

21 is a schematic structural diagram of a display after a third heating step according to an embodiment of the present invention;

22 is a schematic diagram of the display structure after the step of preparing the second functional layer according to the embodiment of the present invention;

23 is a schematic structural diagram of the display after the preparation is completed according to an embodiment of the present invention.

Some components are identified as follows

100, B sub-pixel; 200, G sub-pixel; 300, R sub-pixel;

1. Substrate;

2. Pixel definition layer; 21, through hole; 211, first through hole; 212, second through hole; 213, third through hole;

3. The first functional layer;

4. Pixel organic layer; 41, first sub-pixel organic layer; 42, second sub-pixel organic layer; 43, third sub-pixel organic layer; 401, first sulfur layer; 402, second sulfur layer; 403, third Sulfur layer

5. The second functional layer;

6. Electrode layer.

Best Mode of the Invention

The following describes the preferred embodiments of the present invention in detail in conjunction with the accompanying drawings of the specification to fully introduce the technical content of the present invention to those skilled in the art, to exemplify that the present invention can be implemented, so that the technical content disclosed by the present invention is more clear and makes the present Those skilled in the art can more easily understand how to implement the present invention. However, the present invention can be embodied by many different forms of embodiments. The protection scope of the present invention is not limited to the embodiments mentioned in the text, and the description of the embodiments below is not intended to limit the scope of the present invention.

Directional terms mentioned in the present invention, such as "up", "down", "front", "rear", "left", "right", "inner", "outer", "side", etc. The directions in the figures and the direction words used herein are used to explain and explain the present invention, rather than to limit the protection scope of the present invention.

In the drawings, components with the same structure are denoted by the same numerals, and components with similar structures or functions are denoted by similar numerals. In addition, for ease of understanding and description, the size and thickness of each component shown in the drawings are arbitrarily shown, and the present invention does not limit the size and thickness of each component.

When certain components are described as "on" another component, the component may be directly placed on the other component; there may also be an intermediate component, which is placed on the intermediate component , And the intermediate component is placed on another component. When a component is described as "installed to" or "connected to" another component, the two can be understood to be "installed" or "connected" directly, or a component "installed to" or "connected to" through an intermediate component Another component.

As shown in FIG. 3, the present invention provides a method for manufacturing a display, which specifically includes steps S1 to S6.

S1 The step of preparing the pixel definition layer, providing the substrate 1, coating a layer of pixel definition layer material on the surface of the substrate 1 to obtain the pixel definition layer 2, including more than two pixel unit regions.

In the step of setting S2 through holes, the pixel defining layer 2 in each pixel unit area is provided with three through holes 21, namely a first through hole 211, a second through hole 212, and a third through hole 213, the first through hole 211, The second through hole 212 and the third through hole 213 penetrate through the pixel definition layer 2 and are attached to the upper surface of the substrate 1. In this embodiment, the first through hole 211, the second through hole 212, and the third through hole 213 It is one of R, G, and B pixel vias, which are different from each other (see Figure 4).

S3 The first functional layer preparation step, using a common mask with a large opening to evaporate the first functional layer 3 on the pixel definition layer 2, the first functional layer 3 includes at least one of a hole injection layer and a hole transport layer Species (see Figure 5).

As shown in FIG. 6, the S4 pixel organic layer preparation step sequentially prepares three sub-pixel organic layers, including the S41 first sub-pixel organic layer preparation step to prepare the first sub-pixel organic layer; S42 the second sub-pixel organic layer preparation step , Preparing a second sub-pixel organic layer; and S43 preparing a third sub-pixel organic layer, preparing a third sub-pixel organic layer.

As shown in FIG. 7, the step of preparing the organic layer of the first sub-pixel in S41 specifically includes steps S411 to S413.

S411 The first sulfur layer preparation step, a first mask layer is used to block the first through hole 211 and its surrounding area, and the first sulfur layer 401 is vapor-deposited on the first functional layer 3, without considering the shadow effect, only covering the second sulfur layer The first functional layer 3 above the through hole 212 and the third through hole 213 need not cover the first functional layer 3 above the first through hole 211 (see FIG. 8 ).

S412: Step of preparing the first pixel organic layer, using a common mask with a large opening to vapor-deposit a first pixel organic layer material on the upper surface of the first functional layer 3 to obtain a first pixel organic layer (see FIG. 9).

S413 In the first heating step, the entire surface of the substrate 1 is heated to evaporate or sublimate the sulfur layer, and at the same time, the organic layer of the first pixel attached to the first sulfur layer 401 is peeled off (refer to FIG. 10) The first pixel organic layer is the first sub-pixel organic layer 41 (see FIG. 11).

As shown in FIG. 12, step S42 of preparing the second sub-pixel organic layer specifically includes steps S421-S423.

S421 The second sulfur layer preparation step, using a common mask plate with a large opening to evaporate the second sulfur layer 402 on the first sub-pixel organic layer and the first functional layer 3, without considering the shadow effect, only covering the The first sub-pixel organic layer and the first functional layer 3 above the third through hole 213 need not cover the first functional layer 3 above the second through hole 212 (see FIG. 13 ).

S422 Step of preparing the second pixel organic layer, using a common mask with a large opening to vapor-deposit a second pixel organic layer material on the upper surfaces of the first sub-pixel organic layer 41 and the first functional layer 3 to obtain a second pixel organic layer Layer (see Figure 14).

S423 In the second heating step, the entire surface of the substrate 1 is heated, so that the second sulfur layer 402 evaporates or sublimes, and at the same time, the organic layer of the second pixel attached to the second sulfur layer 402 is peeled off (see FIG. 15), leaving The second pixel organic layer is the second sub-pixel organic layer 42 (see FIG. 16).

As shown in FIG. 17, the step of preparing the organic layer of the third sub-pixel in S43 specifically includes steps S431 to S433.

S431: a third sulfur layer preparation step, using a mask to block the third through hole 213 and its surrounding area, and depositing a third sulfur layer 403 on the first sub-pixel organic layer 41 and the second sub-pixel organic layer 42, Regardless of the shadow effect, only the first sub-pixel organic layer 41 and the second sub-pixel organic layer 42 are covered, and the first functional layer 3 of the third through hole 213 is not covered (see FIG. 18 ).

S432 The third pixel organic layer preparation step, using a common mask with a large opening to vapor-deposit an upper surface of the first functional layer 3 not covered by the third sulfur layer 403 above the third sulfur layer 403 and the third through hole 213 With the third pixel organic layer material, a third pixel organic layer is obtained (see FIG. 19).

S433 The third heating step is to heat the entire surface of the substrate 1 to evaporate or sublimate the third sulfur layer 403, and at the same time, the organic layer of the third pixel attached to the third sulfur layer 403 is peeled off (see FIG. 20) and exposed The first sub-pixel organic layer 41 and the second sub-pixel organic layer 42, and the remaining third pixel organic layer is the third sub-pixel organic layer 43 (see FIG. 21 ).

The first sub-pixel organic layer 41, the second sub-pixel organic layer 42, and the third sub-pixel organic layer 43 in the same pixel unit area are connected in sequence, the first sub-pixel organic layer 41, the second sub-pixel organic layer 42, and the third sub-pixel The organic layer 43 is one of a green organic layer, a blue organic layer, and a red organic layer and is different from each other, that is, the order of the preparation steps of the green organic layer, the blue organic layer, and the red organic layer may be Arbitrary exchange does not affect the final display production.

S5 The second functional layer preparation step, a second functional layer 5 is vapor-deposited on the upper surface of the pixel organic layer 4 using a common mask with a large opening, and the second functional layer 5 includes a hole blocking layer, an electron transport layer, and electrons At least one of the injection layers (see FIG. 22).

S6 electrode layer preparation step, an electrode layer 6 is vapor deposited on the upper surface of the second functional layer 5 using a common mask plate with a large opening, the electrode layer 6 is a cathode layer, including a CPL (Capping layer, light extraction layer), and finally The prepared display is shown in FIG. 23.

As shown in FIG. 23, the display includes a substrate 1, a pixel definition layer 2, a first functional layer 3, a pixel organic layer 4, a second functional layer 5, and an electrode layer 6.

The pixel definition layer 2 is provided on the upper surface of the substrate 1, three through holes 21 penetrate downwardly through the pixel definition layer 2 and are attached to the upper surface of the substrate 1; the first functional layer 3 is attached to the pixel definition layer 2 and the through holes The upper surface of 21; the pixel organic layer 4 is provided on the upper surface of the first functional layer 3; the second functional layer 5 is provided on the upper surface of the pixel organic layer 4; the electrode layer 6 is provided on the upper surface of the second functional layer 5.

The pixel organic layer 4 is divided into three parts, including: a first sub-pixel organic layer 41, a second sub-pixel organic layer 42 and a third sub-pixel organic layer 43, a first sub-pixel organic layer 41, a second sub-pixel organic layer 42 And the third sub-pixel organic layer 43 is sequentially connected and provided on the upper surface of the first functional layer 3.

The sublimation temperature of sulfur in the atmospheric atmosphere is 95°, and the sublimation temperature in vacuum is lower than 80°. However, the current display is baked at 120° for 1 hour, which will not affect the use efficiency and service life of the display. Therefore, the heating process of sulfur will not affect the performance of the display itself.

Taking advantage of sulfur's easy sublimation and evaporation characteristics, the organic layer material overlying the sulfur layer is stripped off as the sulfur sublimates and evaporates, leaving the organic layer material not covering the sulfur area to complete the evaporation of the organic material of each pixel. To achieve the purpose of high pixel density display.

At the same time, the prepared display is a display with high pixel density, without using a precision mask, the preparation process is simple and easy to operate, and the cost of manufacturing and cleaning is saved.

The display can be used as: portable wearable devices such as smart watches and other devices; mobile phones; e-books and electronic newspapers; TV sets; personal portable computers; flexible OLED displays such as foldable and rollable OLED; new and efficient OLED displays; OLED monitors; mobile tools such as in-car displays for cars, trains, etc.; control panels for mechanical equipment, etc.

The display and the preparation method thereof provided by the embodiments of the present invention have been described in detail above. It should be understood that the exemplary embodiments described herein should be considered descriptive only, to help understand the method of the present invention and its core idea, but not to limit the present invention. Descriptions of features or aspects in each exemplary embodiment should generally be considered as applicable to similar features or aspects in other exemplary embodiments. Although the present invention has been described with reference to exemplary embodiments, various changes and modifications may be suggested to those skilled in the art. The present invention is intended to cover these changes and modifications within the scope of the appended claims, and these change box modifications should also be regarded as the protection scope of the present invention.

Claims

A preparation method of a display includes the following steps:

S1: a pixel definition layer preparation step, providing a substrate, and coating a pixel definition layer on the substrate, including more than two pixel unit areas;

In the step of setting S2 through holes, three through holes are provided in the pixel definition layer of each pixel unit area, which are respectively a first through hole, a second through hole and a third through hole;

S3: a first functional layer preparation step, a first functional layer is evaporated on the pixel definition layer;

S4 pixel organic layer preparation step, sequentially preparing three sub-pixel organic layers, corresponding to three through holes;

S5: a second functional layer preparation step, a second functional layer is evaporated on the upper surface of the pixel functional layer; and

S6: an electrode layer preparation step, an electrode layer is evaporated on the upper surface of the second functional layer.
The method for manufacturing a display according to claim 1, wherein:

The steps for preparing the pixel organic layer include:

S41: a first sub-pixel organic layer preparation step, to prepare a first sub-pixel organic layer;

S42: preparing a second sub-pixel organic layer, preparing a second sub-pixel organic layer; and

S43: a third sub-pixel organic layer preparation step, to prepare a third sub-pixel organic layer.
The method for manufacturing a display according to claim 2, wherein:

The step of preparing the first sub-pixel organic layer includes:

S411: a first sulfur layer preparation step, a mask plate is used to block the first through hole and its surrounding area, a first sulfur layer is evaporated on the first functional layer, and the mask plate is removed;

S412: preparing a first pixel organic layer, vapor-depositing a first pixel organic layer material on the upper surface of the first functional layer to obtain a first pixel organic layer; and

S413 The first heating step, heating the substrate, so that the first sulfur layer is evaporated or sublimed, the first pixel organic layer above the first sulfur layer is stripped, and the remaining first pixel organic layer is the first sub-layer Pixel organic layer.
The method for manufacturing a display according to claim 3, wherein

The step of preparing the second sub-pixel organic layer includes:

S421: preparing a second sulfur layer, using a mask to block the second through hole and its surrounding area, and evaporating a second sulfur layer on the first sub-pixel organic layer and the first functional layer, Remove the mask plate;

S422: preparing a second pixel organic layer, vapor-depositing a second pixel organic layer material on the upper surface of the first functional layer to obtain a second pixel organic layer; and

S423 The second heating step, heating the substrate, so that the second sulfur layer is evaporated or sublimed, the second pixel organic layer above the second sulfur layer is stripped, and the remaining second pixel organic layer is the second sub-layer Pixel organic layer.
The method for manufacturing a display according to claim 4, wherein:

The step of preparing the third sub-pixel organic layer includes:

S431: a third sulfur layer preparation step, a third mask is used to block the third through hole and its surrounding area, and third sulfur is evaporated on the first sub-pixel organic layer and the second sub-pixel organic layer Layer to remove the mask;

S432: a third pixel organic layer preparation step, a third pixel organic layer material is deposited on the upper surface of the first functional layer to obtain a third pixel organic layer; and

S433 The third heating step, heating the substrate, so that the third sulfur layer is evaporated or sublimed, the third pixel organic layer above the third sulfur layer is stripped, and the remaining third organic layer is the third sub-pixel organic Floor.
The method for manufacturing a display according to claim 1, wherein:

The first sub-pixel organic layer, the second sub-pixel organic layer and the third sub-pixel organic layer in the same pixel unit area are connected in sequence.
The method for manufacturing a display according to claim 2, wherein:

The first sub-pixel organic layer, the second sub-pixel organic layer, and the third sub-pixel organic layer are one of a green organic layer, a blue organic layer, and a red organic layer and are different from each other.
The method for manufacturing a display according to claim 1, wherein:

The first functional layer includes at least one of a hole injection layer and a hole transport layer.
The method for manufacturing a display according to claim 1, wherein:

The second functional layer includes at least one of a hole blocking layer, an electron transport layer, and an electron injection layer.
The method for manufacturing a display according to claim 1, wherein:

The electrode layer includes a light extraction layer.