KR20190108028A - Metal shadow mask and preparation method thereof - Google Patents

Abstract

The present invention relates to a metal shadow mask and a production method thereof. The production method comprises the following steps of: providing a top plate: serve performing several cyclic processes of coating, exposure, development and electroforming to obtain the metal shadow mask having different aperture sizes on opposite sides; and having a stepped deposition angle of the metal shadow mask through change in the aperture size. The present invention solves a problem in that deposition of the prior art is not uniform and deposition shadow is easily generated by introducing the deposition angle into the metal shadow mask through a layer-by-layer electroforming method.

Description

Metal shadow mask and its manufacturing method {METAL SHADOW MASK AND PREPARATION METHOD THEREOF}

TECHNICAL FIELD The present invention relates to the field of organic light emitting diode display technology, and more particularly, to a metal shadow mask and a method of manufacturing the same.

Organic light-emitting diode (OLED) display devices are manufactured using organic semiconductor materials and are thin film light emitting devices driven by a direct current voltage. OLED display devices have become the mainstream of next-generation display technology with the advantages of slim, light, high contrast, and wide vision.

The light emitting principle of the OLED display device is that when the current is coated through the organic light emitting material, that is, the organic light emitting material coating emits light. Currently in the manufacturing field of the OLED industry, a method of shadow mask deposition for single deposition is generally used, in which the organic material particles adhere to the substrate through the openings of the shadow mask from each angle. However, in the normal deposition process, the openings distributed in the shadow mask are tapered, and when the particles face the opening obliquely, some particles are covered by the opening walls and cannot reach the substrate, resulting in the lack of obliquely entering particles. Thus, the deposition of the substrate is not uniform, so that a shadowing effect may occur, and the brightness of the product is reduced, thereby affecting the display characteristics of the OLED element.

Currently, in the shadowing effect, the manufacturing of shadow masks for OLEDs is generally made by using a double-sided etched metal coil material, but this method cannot accurately control the uniformity of the opening size. Shadow masks have an inverse taper angle at the contact surface openings of indium tin oxide (ITO), creating a rectangular area, which affects the deposition quality.

An object of the present invention is to provide a metal shadow mask and a method of manufacturing the same, to solve the problem that the shadow effect is easily generated when the glass substrate is deposited.

In order to solve the above problems, the present invention provides a method for producing a metal shadow mask, comprising the steps of: providing a base plate; Installing a photosensitive film on the mother plate; Exposing and developing the photoresist to form a plurality of first structures on the mother plate; Forming a first layer metal layer on the mother plate; Removing the plurality of first structures to form a plurality of first openings corresponding to the plurality of first structures in the first layer metal layer; Forming the photosensitive film on the first layer metal layer; Exposing and developing to form a plurality of second structures corresponding to the plurality of first openings in the photosensitive film, wherein the size of the second structure is larger than the size of the first openings; Forming a second layer metal layer on the first layer metal layer and combining the first layer metal layer with a metal shadow mask; And removing the plurality of second structures to form a plurality of second openings corresponding to the plurality of first openings in the second layer metal layer.

The present invention also provides a metal shadow mask manufactured through the above manufacturing method.

Compared with the prior art, the present invention includes the following technical effects.

The metal shadow mask and its manufacturing method provided by this invention introduce | transduce a deposition angle into an electroplating metal shadow mask through the method of layered precast metal plating, and form a stepped perforated structure, By controlling the thickness of the one-layer metal layer to 1 to 2 um, the deposition shadow can be reduced or eliminated. In addition, upon deposition, the loss of organic material particles incident on the glass substrate can be reduced, thereby improving deposition uniformity and reducing the brightness of the product.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings described herein constitute part of the present invention as an additional understanding of the present invention, and exemplary embodiments of the present invention and the description thereof are intended to interpret the present invention and do not limit the present invention. In the drawing,
1 is a method flow diagram of an embodiment of the present invention.
Figure 2 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
3 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
Figure 4 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
5 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
6 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
7 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
8 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
9 is a side view corresponding to different manufacturing steps in the embodiment of the present invention.
10 is a cross-sectional view of a metal shadow mask of an embodiment of the invention.

DETAILED DESCRIPTION Hereinafter, the embodiments of the present invention will be described in detail with reference to the accompanying drawings and examples, whereby the present invention fully understands and implements how the present invention solves technical problems and achieves technical effects by using technical solutions. Do it.

Any word in the specification and claims refers to a particular member. One skilled in the art understands that in hardware manufacturing, the same elements may be referred to by different names. The specification and claims do not distinguish members by differences in names, and in principle, members are classified by functional differences. “Included” in the entire specification and in the claims is to be understood as an open term, “including but not limited to”. “Alternatively” refers to an acceptable error range, and the person skilled in the art solves the technical problem within a certain error range, and achieves the technical effect. In addition, the word “coupling” or “electrically connected” includes any direct or indirect electrical coupling means. Thus, when the sentence states that the first device is coupled to the second device, the first device is electrically electrically coupled to the second device, or via the other device or coupling means, the second device. Refers to electrically indirectly coupled to. The following description of the specification is a preferred embodiment of the present invention, which is still intended to explain the general principles of the present invention and does not limit the scope of the present invention. The protection scope of the invention is based on what is set forth in the claims.

It should be further explained that not only include such an element as a process, method, product or system of elements, but is also clearly defined by encompassing non-exclusive inclusion of the term “inclusive”, “inclusive” or other form of change. It may also include other elements not explicitly listed, or further include elements unique to such processes, methods, goods or systems. In the absence of further limitations, the elements of the definition of “comprise one” do not exclude the inclusion of a separate identical element present in the process, method, product or system of the element. .

Example

As shown in FIG. 1, in one embodiment of the present invention, a method of manufacturing a metal shadow mask includes the following steps.

Step S101: Provide the mother bed. The clean platen of the pretreatment process, or the platen with an acidic and alkaline detergent prior to this step, then rinsed with deionized water and then dried to prepare for use.

Step S103: Install a photosensitive film on the mother plate. Mainly pressing the photosensitive film 20 to the base plate 10 at a constant pressure with a roller of a constant temperature, so that the surface of the photosensitive film 20 and the base plate 10 is sufficiently bonded (shown in Figure 2).

Step S105: Exposure and development cause the photosensitive film to form a plurality of first structures on the mother plate. 2 and 3, in the above step, the photosensitive film 20 is coated with the base plate 10 so that the photosensitive film 20 forms a first layer pattern according to the exposure pattern; Next, the base plate 10 after exposure to a constant temperature is baked, and the exposed photosensitive film 20 is sufficiently reacted; Thereafter, the exposed base plate 10 is developed so that the photosensitive film 20 forms a plurality of first structures 30 (that is, a dry thin film after the photosensitive film is exposed and developed) on the surface of the base plate 10, First structures 30 are arranged spaced apart from each other.

Here, the base plate 10 having a plurality of first structures 30 may be hard-baked or UV solidification may be selectively performed. After development, the base plate 10 is baked at a relatively high temperature and then, The first structure 30 is more firm and the adhesion to the surface of the base plate 10 is stronger.

Step S107: A first layer metal layer is formed on the mother plate. As shown in FIG. 4, the base plate 10 having a plurality of first structures 30 is electroplated to form a layer at a position where the first structure 30 is not provided on the surface of the base plate 10. The metal layer 40 is deposited to form the first layer metal layer 40 of the metal shadow mask, and the thickness H1 of the metal layer 40 is approximately 1 to 5 um, for example, 1 to 2 um. In this step, the base plate 10 having a plurality of first structures 30 is left in the electroplating plating solution, and the electrode plate 10 is subjected to an electrodeposition process under an appropriate temperature. For example, the mother plate 10 is left in the electroplating plating solution having a pH value of 2 to 3.5, and the electroplating process is performed under a temperature of 40 to 60 ° C. In some embodiments of the present invention, the plating of the electroplating base plate may proceed the electroplating process at a temperature of 50 ℃ in the electroplating plating solution pH value 3. It also controls the current of the iron anode and nickel anode, respectively, via a rectifier, for example a double rectifier, where the current supply scheme can proceed using a direct current with a current value of 4 A / dm ² . Therefore, in the above step, an iron nickel alloy layer having a thickness of 1 to 5 um can be obtained, and the thickness is uniformly controlled in the range of 0.1 to 0.5 um.

Here, the components of the electroplating solution are nickel sulfate 40-80 g / L, ferrous sulfate 20-40 g / L, antioxidant 1-2 g / L, positive active agent 10-20 g / L and complexing agent 0.2-0.4 g / L. An iron nickel alloy layer having an iron content of 40% to 70% may be obtained through the electroplating process. In other embodiments of the present invention, the electroplating plating solution may further comprise a pH buffer of 30-45 g / L and / or a complex stabilizer of 2-10 g / L, wherein the use of the composite stabilizer may be in the form of an iron nickel alloy layer. The brightness can reach level 2 brightness.

Through the electroplating process, it is possible to plate the thin side (first layer metal layer) of <2um uniform thickness on the mother plate, thereby obtaining a result of optimizing up to <10% in terms of uniformity. On this basis, it is possible to realize the stepped structure of the small deposition shadows required for OLED deposition in multiple gold shadow masks in conjunction with subsequent manufacturing processes.

Step S109: Remove the plurality of first structures to form a plurality of first openings corresponding to the plurality of first structures in the first layer metal layer. 4 and 5, the base plate 10 having a plurality of first structures 30 after the main electroplating is placed in the film removing groove and the film removing process is performed, and the patterning plate 10 is not patterned. Clean the photoresist. That is, by removing the plurality of first structures 30 from the mother plate, a plurality of first openings 41 are formed in the first layer metal layer 40. The position and shape of the plurality of first openings 41 and the position and shape of the plurality of first structures 30 match each other.

Then, before proceeding to the next step, the washing and drying process for the base plate 10 after the film is removed selectively proceeds, for example, washed clean with deionized water, the base plate 10 can be dried have.

Step S111: A photosensitive film is formed on the first layer metal layer. As illustrated in FIG. 6, the photosensitive film 20 is pressed onto the metal layer 40 at a constant pressure by using the roller 10 having the first layer metal layer 40 provided thereon with a roller of a constant temperature, and the photosensitive film 20 and The surface of the metal layer 40 is sufficiently bonded.

Step S113: by exposure and development, a plurality of second structures corresponding to the plurality of first openings are formed in the photosensitive film, and the size of the second structure is larger than the size of the first opening. In operation, the photosensitive film is formed to form a second layer pattern in accordance with the exposure pattern with respect to the mother plate exposure on which the photosensitive film is pressed. Subsequently, the mother plate after exposing at constant temperature is baked, and the exposed photosensitive film is sufficiently reacted. Then, as shown in Figs. 6 and 7, the substrate 10 after exposure is developed to dry after exposing and developing a plurality of second structures 50 (that is, photosensitive film 20) on the photosensitive film 20. Thin film). The plurality of second structures 50 correspond to the plurality of first openings 41 one by one, the size of the second structure 50 is slightly larger than the size of the first opening 41, and the first openings 41 may be formed. It shields and the 1st layer metal layer 40 covers the 1st opening 41 and the periphery which adjoin each other.

After this step, a hard baking or UV solidification process may be selectively performed on the base plate 10, and the developed base plate 10 is baked at a relatively high temperature, so that the plurality of second structures 50 are more robust. And the adhesion is further strengthened.

Step S115: A second layer metal layer is formed on the first layer metal layer, and is combined with the first layer metal layer with a metal shadow mask. As shown in FIG. 8, the base plate 10 having the plurality of second structures 50 is electroplated to form a layer at a position where the second structure 50 is not provided in the first layer metal layer 40. The metal layer 60 is deposited to form the second layer metal layer 60 of the metal shadow mask, and the thickness H2 of the metal layer 60 is thicker than the thickness H1 of the first layer metal layer 40, and both The thickness ratio of can reach 1: 5 to 1:25, 1:10, 1:15 or 1:20. For example, when the thickness H1 of the first layer metal layer 40 is 1 um, the thickness H2 of the second layer metal layer 60 may be between 5 and 25 um, for example, 5 um, 15 um, or 25 um. . When the thickness H1 of the first layer metal layer 40 is 2 μm, the thickness H2 of the second layer metal layer 60 may include 10 μm, 20 μm, or 25 μm, but is not limited thereto.

Step S117: Remove the plurality of second structures to form a plurality of second openings corresponding to the plurality of first openings in the second layer metal layer. 8 and 9, in the step, the base plate 10 having the plurality of second structures 50 after the electroplating is placed in a film removing groove, and the film removing process is performed. The photoresist of the substrate is cleanly controlled, the plurality of second structures 50 are removed from the mother plate 10, and the plurality of second openings 61 are formed in the second layer metal layer 60, thereby opening different metal layers and different openings. Obtain a metal shadow mask 70 having a size. Here, the positions of the plurality of second openings 61 correspond to the plurality of first openings 41 one by one, and also communicate with the plurality of first openings 41. It should be explained that, through the above manufacturing process, the center shift amount of the center of the second opening 61 and the corresponding center shift amount of the first opening 41 can be controlled to be about 0.5 um to 1 um. By precisely symmetry of the center point positions of the openings between the layers, the bonding between the layers and the layers is more precise, ensuring the precision of the position of the openings, and is advantageous for the manufacture of the metal shadow mask 70 of small openings.

After the film removing process, the washing and drying process may be selectively performed on the mother plate 10 after the film is removed. Finally, the metal shadow mask 70 is again removed from the mother plate 10 and fixed (shown in FIG. 10).

9 and 10, in an embodiment of the present invention, the metal shadow mask 70 manufactured through the process includes a first layer metal layer 40 and a second layer metal layer 60. The constituent materials of the first layer metal layer 40 and the second layer metal layer 60 include, but are not limited to, nickel alloys, nickel-cobalt alloys, and iron nickel alloys. The first layer metal layer 40 has a plurality of first openings 41, which are arranged spaced apart from each other and also penetrate the first layer metal layer 40. The second layer metal layer 60 has a plurality of second openings 61, and positions of the plurality of second openings 61 correspond to the plurality of first openings 41 one by one, and in the horizontal direction, respectively. The size (diameter) of the second opening 61 of the first opening 41 is larger than the size (diameter) of each of the first openings 41, and the first and second openings 41 and 2 through which the metal shadow mask 70 communicates with each other ( 61) The staircase structure should be formed inside. In the above structure, due to the difference in size of the apertures, the first layer metal layer 40 is adjacent to the first opening 41 at the same side of the corresponding first opening 41 and the second opening 61. There is a width difference ΔW between the side edges and one side edge of the second layer metal layer 60 adjacent to the second opening 61. In addition, the sidewalls of the first layer metal layer 40 adjacent to the first opening 41 and the sidewalls of the second layer metal layer 60 adjacent to the second opening 61 and the metal shadow mask 70 may be formed. A narrow angle θ is provided between the surfaces (that is, the surfaces of the first or second layer metal layers 40 and 60), and the angle of the narrow angle θ can be any angle larger than 0 ° and smaller than 90 °. Preferably, the angle is a narrow angle [theta] of 30 to 60 degrees. Here, the angular size of the narrow angle θ can be correspondingly adjusted through the width difference ΔW, and when deposited, the organic material particles have a relatively preferred angle of incidence, thereby reducing or eliminating the shading effect.

In addition, since the deposition shadow is influenced by the deposition angle, the deposition shadow is directly proportional to the vertical distance of the glass substrate and the break point of the deposition material, and thus, for the first layer metal layer in contact with the glass substrate, the thickness is 1 It can be controlled to between 5um, for example 1um or 2um, it can effectively reduce the generation of the shadow effect.

Although the above description has described a number of preferred embodiments of the present invention, the above contents are for the purpose of understanding the present invention and do not limit the form disclosed in the text, and should not be regarded as an exclusion of other embodiments, and various other combinations and corrections. And it can be applied to the environment, it can be modified through the skills or knowledge of the prison or related fields within the scope of the invention of the text. Modifications and changes in the art without departing from the spirit and scope of the present invention all fall within the scope of the appended claims.

Claims (20)

Providing a mother bed;
Installing a photosensitive film on the mother plate;
Exposing and developing the photoresist to form a plurality of first structures on the mother plate;
Forming a first layer metal layer on the mother plate;
Removing the plurality of first structures to form a plurality of first openings corresponding to the plurality of first structures in the first layer metal layer;
Installing the photosensitive film on the first layer metal layer;
Exposing and developing to form a plurality of second structures corresponding to the plurality of first openings in the photosensitive film, the size of the second structure being larger than the size of the first openings;
Forming a second layer metal layer on the first layer metal layer and combining the first layer metal layer with a metal shadow mask; And
Removing the plurality of second structures to form a plurality of second openings corresponding to the plurality of first openings in the second layer metal layer; Method of producing a metal shadow mask comprising a.
The method of claim 1,
After the exposing and developing, performing a solidification process on the plurality of first structures or the plurality of second structures; Method of producing a metal shadow mask further comprises.
The method of claim 1,
After removing the plurality of second structures, removing and fixing the metal shadow mask from the mother plate; Method of producing a metal shadow mask further comprises.
The method of claim 1,
Washing and drying the mother plate after removing the film after the step of removing the plurality of first structures or the step of removing the plurality of second structures; Method of producing a metal shadow mask further comprises.
The method of claim 1,
The thickness ratio of the first layer metal layer and the second layer metal layer is 1: 5 to 1:25 manufacturing method of the metal shadow mask.
The method of claim 1,
The center shift amount of the said 1st opening and said 2nd opening is a manufacturing method of the metal shadow mask characterized by the above-mentioned.
The method of claim 1,
And the second opening is in communication with the corresponding first opening and further forms a stepped structure inside the metal shadow mask.
The method of claim 7, wherein
A width difference is provided between one side of the first layer metal layer adjacent to the first opening and one side of the second layer metal layer adjacent to the second opening. .
The method of claim 7, wherein
A narrow angle is provided between a connection line of a side of the first layer metal layer adjacent to the first opening and a side of the side of the second layer metal layer adjacent to the second opening and a surface of the metal shadow mask. Wherein the angle is less than 90 °.
The method of claim 9,
The angle of the narrow angle is a method of manufacturing a metal shadow mask, characterized in that between 30 ° to 60 °.
The method of claim 1,
Forming the first layer metal layer on the mother plate is a method of manufacturing a metal shadow mask, characterized in that the electroplating process in the electroplating plating solution having a pH value of 2 to 3.5, the temperature of 40 ℃ to 60 ℃.
The method of claim 11,
The electroplating plating solution is 40 g / L to 80 g / L nickel sulfate, 20 g / L to 40 g / L ferrous sulfate, 1 g / L to 2 g / L of antioxidant, 10 g / L to 20 g / L of the positive electrode active agent and Method for producing a metal shadow mask, characterized in that it comprises from 0.2g / L to 0.4 g / L complexing agent.
The method of claim 12,
The electroplating plating solution is a method of manufacturing a metal shadow mask, characterized in that it further comprises 2g / L to 10 g / L of a composite stabilizer.
A metal shadow mask made according to the method of claim 1.
The method of claim 14,
And a thickness ratio of the first layer metal layer and the second layer metal layer is 1: 5 to 1:25.
The method of claim 14,
The center shadow amount of the first opening and the second opening is between 0.5um to 1um, the metal shadow mask.
The method of claim 14,
And the second opening is in communication with the corresponding first opening and also forms a stepped structure inside the metal shadow mask.
The method of claim 17,
The width of the metal shadow mask, characterized in that the width difference is provided between one side of the first layer metal layer adjacent to the first opening and the second side of the metal layer adjacent to the second opening.
The method of claim 17,
A narrow angle is provided between a connection line of a side of the first layer metal layer adjacent to the first opening and a side of the side of the second layer metal layer adjacent to the second opening and a surface of the metal shadow mask. Metal shadow mask, characterized in that the angle is less than 90 °.
The method of claim 19,
And the angle of the narrow angle is between 30 ° and 60 °.

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