Mask metal film, mask metal film support template, mask support template and manufacturing method thereof

Abstract

The present invention relates to a mask metal film, a mask metal film support template and a manufacturing method thereof. The mask metal film of the present invention is used to manufacture a mask for forming OLED pixels, and at least comprises a central portion of a metal film (sheet) manufactured by a rolling process, and at least one surface comprises a circular defect or an elliptical defect with a ratio of x-axis length to y-axis length of 1:1 to 3:1.

Description

Technical Field

[0001] The present invention relates to a mask metal film, a mask metal film support template, a mask support template and a manufacturing method thereof. More specifically, the present invention relates to a mask metal film, a mask metal film support template, a mask support template and a manufacturing method thereof, which can form a fine mask pattern on a mask, prevent the mask from being deformed and can be stably supported and moved, and can accurately align the masks on a frame. Background Art

[0002] As a technology for forming pixels in the OLED manufacturing process, the FMM (Fine Metal Mask) method is mainly used. In this method, a metal mask (Shadow Mask) in the form of a thin film is closely attached to a substrate and an organic substance is deposited at a desired position.

[0003] The existing mask manufacturing method is manufactured by preparing a metal sheet used as a mask, performing patterning after PR coating on the metal sheet, or after PR coating for forming a pattern, etching to manufacture a mask with a pattern. In ultra-high-definition OLEDs, the existing QHD picture quality is 500-600PPI (pixel per inch), and the pixel size reaches about 30-50μm, while 4K UHD and 8K UHD have higher resolutions of ~860PPI, ~1600PPI, etc. Therefore, it is necessary to develop a technology that can accurately adjust the size of the mask pattern.

[0004] In addition, in the existing OLED manufacturing process, after the mask is manufactured into a strip shape, a plate shape, etc., the mask is welded and fixed to the OLED pixel deposition frame and used. In order to manufacture large-area OLEDs, multiple masks can be fixed to the OLED pixel deposition frame, and in the process of fixing them to the frame, each mask is stretched to make it flat. Adjusting the stretching force to make the entire part of the mask flat is a very difficult task. In the process of fixing multiple masks to a frame, there is still a problem of poor alignment between masks and between mask units. In addition, in the process of welding the mask to the frame, the thickness of the mask film is too thin and the area is large, so there is a problem of the mask sagging or twisting due to the load.

[0005] In this way, considering the pixel size of ultra-high-definition OLED, the alignment error between each unit needs to be reduced to about several μm. If the error exceeds this, the product will be defective, so the yield may be extremely low. Therefore, it is necessary to develop a technology that can prevent deformation such as sagging or twisting of the mask and make the alignment accurate, as well as a technology to fix the mask to the frame. Summary of the invention

[0006] Technical issues

[0007] Therefore, the present invention is proposed to solve the various problems of the prior art as described above, and its object is to provide a mask metal film capable of forming a fine mask pattern on a mask, a mask metal film support template, a mask support template and a manufacturing method thereof.

[0008] Another object of the present invention is to provide a method for manufacturing a frame-integrated mask that can prevent deformation such as sagging or twisting of the mask and accurately align the mask.

[0009] Technical Solution

[0010] The above-mentioned purpose of the present invention is achieved by a mask metal film supporting template, which is used to support the mask metal film used in manufacturing a mask for forming OLED pixels and correspond it to a frame. The template includes: a template; a temporary bonding portion formed on the template; and a mask metal film, which is bonded to the template by clamping the temporary bonding portion. The mask metal film includes at least a central portion of a metal film manufactured by a rolling process, and at least one surface includes a circular defect or an elliptical defect with a ratio of x-axis length:y-axis length of 1:1 to 3:1.

[0011] The mask metal film may be in a state where no particles exist in the circular or elliptical defects.

[0012] The angle that the side surface of the defect of the mask metal film may form with the xy plane is 0° to 30°.

[0013] The width of the defect of the mask metal film may be less than 30 μm (exceeding 0).

[0014] The x-axis may be parallel to the rolling direction.

[0015] By performing a surface defect removal process and a thickness reduction process on at least one side of the metal film manufactured by the rolling process, the mask metal film may have a thickness of 5 μm to 20 μm.

[0016] A surface defect removal process is performed on 2.5% to 12.5% ​​of the initial baseline thickness of the mask metal film, so that the defect morphology, i.e., the ratio of the x-axis length: the y-axis length, changes from k:l to m:n, wherein k and l are positive numbers, k is a number greater than 1, m and n are positive numbers, and k / l>m / n can be satisfied.

[0017] The surface defect removal process may be performed by any one of lapping, polishing, and buffing, and the thickness reduction process may be performed by wet etching.

[0018] The mask metal film includes a mask unit region as a region for forming a mask pattern and a dummy region around the mask unit region, and a portion of the dummy region corresponding to the soldering portion may have a thickness greater than at least a thickness of a remaining region.

[0019] Based on the thickness of the mask metal film manufactured by the rolling process, when the upper surface is 0% and the lower surface is 100%, the central portion may use at least a portion corresponding to 10% to 90% of the thickness of the mask metal film.

[0020] In addition, the above-mentioned purpose of the present invention is achieved by a method for manufacturing a mask support template, wherein the template is used to support a mask for forming OLED pixels and correspond it to a frame, and the method includes the following steps: (a) bonding a mask metal film manufactured by a rolling process to a template having a temporary bonding portion formed on one side; (b) removing surface defects and reducing the thickness on the first side of the mask metal film; (c) reducing the thickness on the first side of the mask metal film by etching.

[0021] Step (a) may include the following steps: (a1) forming an insulating portion on the second surface, which is the opposite side of the first surface of the mask metal film; (a2) bonding the mask metal film to the upper surface of the template by clamping the insulating portion on a template having a temporary bonding portion formed on one side.

[0022] The method may further include the following steps: (d) separating the mask metal film from the template; (e) bonding the first side of the mask metal film to a second template having a temporary bonding portion formed on one side; (f) removing surface defects and reducing the thickness on the second side, which is the opposite side of the first side of the mask metal film; and (g) reducing the thickness of the second side of the mask metal film by etching.

[0023] The thickness reduction in step (b) may be performed to 2.5% to 12.5% ​​of the initial reference thickness of the mask metal film.

[0024] Step (b) can be performed by any one of lapping, polishing and buffing.

[0025] The thickness reduction in step (c) may be performed by a greater amount than the thickness reduction in step (b).

[0026] Step (c) may be performed by wet etching.

[0027] After step (c), the thickness of the mask metal film may be 5 μm to 20 μm.

[0028] After step (b), the defect morphology on the first surface, i.e., the ratio of the x-axis length: the y-axis length, changes from k:l to m:n, wherein k and l are positive numbers, k is a number greater than 1, m and n are positive numbers, and k / l>m / n is satisfied.

[0029] After step (b), particles included in defects on the first face may be removed.

[0030] After step (b), an insulating portion is formed on a region remaining except for the mask unit portion of the mask metal film or on a solder portion region of the mask metal film, and step (c) is performed on a region where the insulating portion is not formed.

[0031] In addition, the above-mentioned purpose of the present invention is achieved by a method for manufacturing a mask support template, wherein the mask support template is used to support a mask for forming OLED pixels and correspond it to a frame, the method comprising the following steps: (a) bonding a mask metal film manufactured by a rolling process to a template having a temporary bonding portion formed on one side; (b) removing surface defects and reducing the thickness on the first side of the mask metal film; (c) reducing the thickness on the first side of the mask metal film by etching; and (d) manufacturing a mask by forming a mask pattern on the mask metal film.

[0032] In addition, the above-mentioned purpose of the present invention is achieved by a method for manufacturing a mask support template, wherein the mask support template is used to support a mask for forming OLED pixels and correspond it to a frame, the method comprising the following steps: (a) preparing a mask metal film manufactured by a rolling process; (b) removing surface defects and reducing the thickness on the first side of the mask metal film; (c) reducing the thickness by etching on the first side of the mask metal film; (d) manufacturing a mask by forming a mask pattern on the mask metal film; and (e) bonding the mask to a template having a temporary bonding portion formed on one side.

[0033] In addition, the above-mentioned purpose of the present invention is achieved by a mask metal film, which is used to manufacture a mask for forming OLED pixels, and includes at least a central portion of a metal film (sheet) manufactured by a rolling process, and at least one surface includes a defect having a circular shape or an elliptical shape with a ratio of x-axis length:y-axis length of 1:1 to 3:1.

[0034] In addition, the above-mentioned purpose of the present invention is achieved by a method for manufacturing a mask metal film, which includes the following steps: (a) preparing a mask metal film (sheet) manufactured by a rolling process; (b) removing surface defects and reducing the thickness on the first side of the mask metal film; and (c) reducing the thickness on the first side of the mask metal film by etching.

[0035] In addition, the above-mentioned purpose of the present invention is achieved by a method for manufacturing a mask metal film, wherein the frame-integrated mask is formed integrally by at least one mask and a frame for supporting the mask, wherein the method includes the following steps: (a) loading the mask support template manufactured by the described method onto a frame having at least one mask unit area so that the mask corresponds to the mask unit area of ​​the frame; (b) attaching the mask to the frame.

[0036] Beneficial Effects

[0037] According to the present invention as described above, there is an effect that a fine mask pattern can be formed on a mask.

[0038] Furthermore, according to the present invention, there is an effect that deformation such as sagging or twisting of the mask can be prevented and the mask can be accurately aligned. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 1 is a front view and a side cross-sectional view of a frame-integrated mask according to an embodiment of the present invention.

[0040] Figure 2 is a schematic diagram of a mask according to an embodiment of the present invention.

[0041] Figure 3 2 is a schematic diagram of a mask metal film and a schematic diagram of surface defects of the mask metal film according to an embodiment of the present invention.

[0042] Figure 4 FIG. 4 is a schematic diagram of a manufacturing process of a mask metal film according to an embodiment of the present invention.

[0043] Figure 5 is a schematic diagram of a process of manufacturing a mask metal film on a mask support template according to an embodiment of the present invention.

[0044] Figure 6 FIG. 4 is a schematic diagram of a process of forming a mask by bonding a mask metal film on a template to manufacture a mask support template according to an embodiment of the present invention.

[0045] Figure 7 2 is a schematic diagram of a state in which a template is loaded onto a frame so that the mask corresponds to a unit area of ​​the frame according to an embodiment of the present invention.

[0046] Figure 8 FIG. 2 is a schematic diagram of a process of separating the mask from the template after attaching the mask to the frame according to an embodiment of the present invention.

[0047] Fig. 9 is a schematic diagram of a state where a mask is attached to a unit region of a frame according to an embodiment of the present invention.

[0048] Fig.10Surface photographs of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention.

[0049] Fig.11 Surface optical microscope photographs of a defective sample of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention.

[0050] Fig.12 The following are surface AFM (Atomic Force Microscope) photos of a defective sample of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention.

[0051] Figures 13 to 16 The optical microscope photographs at various magnifications are taken on a defective sample of a mask metal film before and after a surface defect removal process according to an experimental example.

[0052] Reference numerals:

[0053] 40, 45: Support substrate 41, 46: Adhesive

[0054] 50: Template 51: Laser through hole

[0055] 55: Temporary bonding part 100: Mask

[0056] 110, 110', 110": mask film, mask metal film

[0057] 111': first surface of the mask metal film 112': second surface of the mask metal film

[0058] 113': first surface layer of the mask metal film

[0059] 114': second surface layer of the mask metal film

[0060] 115': center portion of the mask metal film 116': upper layer portion of the mask metal film

[0061] 117 ′: lower layer of the mask metal film 200: frame

[0062] 210: Edge frame portion 220: Mask unit sheet portion

[0063] 221: Edge sheet portion 223: First grid sheet portion

[0064] 225: Second grid sheet section 1000: OLED pixel deposition device

[0065] C: Cell, mask cell CR: mask cell region

[0066] DM: dummy part, mask dummy part L: laser

[0067] P: Mask pattern PS1: Surface defect removal process

[0068] PS2: Thickness reduction process WB: Welding beads

[0069] WP: Welding Department DETAILED DESCRIPTION

[0070] Below, the present invention is described in detail with reference to the accompanying drawings, which are used to illustrate examples of specific embodiments that can be implemented as the present invention. These embodiments are described in detail so that those skilled in the art can fully implement the present invention. Various embodiments of the present invention should be understood to be different from each other but not mutually exclusive. For example, the specific shapes, structures and characteristics recorded herein can be implemented as other embodiments without exceeding the spirit and scope of the present invention. In addition, the position or arrangement of individual components in each disclosed embodiment should be understood to be changeable without exceeding the spirit and scope of the present invention. Therefore, the following detailed description is not intended to limit the present invention. As long as it can be properly explained, the scope of the present invention is limited only by the attached claims and all scopes equivalent thereto. Similar figure marks in the drawings refer to the same or similar functions in various aspects. For convenience, length, area, thickness, etc. and their forms can also be exaggerated.

[0071] Figure 1 is a front view of a frame-integrated mask according to an embodiment of the present invention. Figure 1 (a)] and side cross-sectional view [ Figure 1 (b)].

[0072] Below, this specification briefly describes the structure of the frame-integrated mask, but the structure and manufacturing process of the frame-integrated mask can be understood as introducing the entire content of Korean Invention Patent Application No. 2018-0016186.

[0073] The existing rod-shaped mask has the following problem. Since multiple mask units are included in one mask, even if the tensile force applied to each axis of the rod-shaped mask is finely adjusted, the alignment between the mask units will be poor. An example of this is that the distances between the patterns of the units are different or the patterns P are not aligned. The long rod-shaped mask is easy to sag or twist due to the load. In order to make all the units in a flat state, it is a very difficult task to adjust the tensile force while observing the alignment state between the units through a microscope. The present invention can prevent the mask 100 formed integrally with the frame 200 from deformation such as sagging or twisting and can accurately align it with the frame 200.

[0074] Reference Figure 1, the frame-integrated mask may include a plurality of masks 100 and a frame 200. In other words, the plurality of masks 100 are attached to the frame 200. Below, for the sake of convenience, a quadrangular mask 100 is used as an example for explanation, but before the mask 100 is attached to the frame 200, it may be a strip-shaped mask with protrusions on both sides for clamping, and the protrusions may be removed after being attached to the frame 200.

[0075] A plurality of mask patterns P are formed on each mask 100, and one cell C may be formed on one mask 100. One mask cell C may correspond to one display of a smartphone or the like.

[0076] The mask 100 may also be made of materials such as invar, super invar, nickel (Ni), nickel-cobalt (Ni-Co), etc. The mask 100 may be made of a metal sheet produced by a rolling process or electroforming.

[0077] The frame 200 may be formed in a form of attaching a plurality of masks 100. Considering thermal deformation, the frame 200 is preferably formed of a material such as Invar, Super Invar, nickel, nickel-cobalt, etc. having the same thermal expansion coefficient as the mask. The frame 200 may include an edge frame portion 210 having a substantially quadrangular shape or a square frame shape. The interior of the edge frame portion 210 may be hollow.

[0078] In addition, the frame 200 has a plurality of mask unit regions CR, and may include a mask unit sheet portion 220 connected to the edge frame portion 210. The mask unit sheet portion 220 may be composed of an edge sheet portion 221, a first grid sheet portion 223, and a second grid sheet portion 225. The edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 are portions divided on the same sheet, and they are integrated with each other.

[0079] The thickness of the edge frame portion 210 may be greater than that of the mask unit sheet portion 220, and may be formed with a thickness of several mm to several tens of cm. Although the thickness of the mask unit sheet portion 220 is thinner than that of the edge frame portion 210, it is thicker than the mask 100, and may be approximately 0.1 mm to 1 mm. The width of the first grid sheet portion 223 and the second grid sheet portion 225 may be approximately 1-5 mm.

[0080] In the planar sheet, a plurality of mask unit regions CR (CR11-CR56) may be provided in addition to the regions occupied by the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225.

[0081] The mask 200 has a plurality of mask unit regions CR, and each mask 100 can be attached in a manner that each mask unit C corresponds to each mask unit region CR. The mask unit C corresponds to the mask unit region CR of the frame 200, and part or all of the dummy portion can be attached to the frame 200 (mask unit sheet portion 220). Therefore, the mask 100 and the frame 200 can form an integrated structure.

[0082] Figure 2 is a schematic diagram of a mask 100 according to an embodiment of the present invention.

[0083] The mask 100 may include a mask unit C formed with a plurality of mask patterns P and a dummy portion DM around the mask unit C. The mask 100 may be manufactured using a metal sheet produced by a rolling process, electroforming, etc., and one unit C may be formed in the mask 100. The dummy portion DM corresponds to a portion of the mask film 110 [mask metal film 110] other than the unit C, and may include only the mask film 110, or include the mask film 110 formed with a predetermined dummy portion pattern similar to the mask pattern P. The dummy portion DM corresponds to an edge of the mask 100, and a portion or all of the dummy portion DM may be attached to the frame 200 [mask unit sheet portion 220].

[0084] The width of the mask pattern P may be less than 40 μm, and the thickness of the mask 100 may be about 5-20 μm. Since the frame 200 has a plurality of mask unit regions CR (CR11-CR56), it may also have a plurality of masks 100, wherein the mask 100 has a mask unit C (C11-C56) corresponding to each mask unit region CR (CR11-CR56). In addition, a plurality of templates 50 may be provided for respectively supporting the plurality of masks 100 described later.

[0085] Figure 3 1 and 2 are schematic diagrams of a mask metal film (a) and surface defects of the mask metal film [(b), (c)] according to an embodiment of the present invention.

[0086] In order to Figure 2 In manufacturing the mask 100, a process of forming a mask pattern P is required on the mask metal film 110. The mask pattern P can be formed by etching or the like. In order to realize an OLED with a high resolution above UHD, the width of the mask pattern P should be less than 40 μm, and considering that the mask pattern P has a tapered shape and an inclined shape, the thickness of the mask metal film used should also be thinner than 20 μm.

[0087] Since the mask pattern P needs to be finely formed, the shape and direction of the grains in the mask metal film 110' should also be considered when performing etching. The etching rate will be different depending on the directionality of the grains. If uneven grains are etched, it may be difficult to generate a mask pattern P of the desired width. Even an error of several μm will affect the implementation of high resolution.

[0088] Reference Figure 3 (a), generally speaking, for a metal film (sheet) generated by rolling, the surface, i.e., the upper surface and the lower surface, have differences in the morphology and direction of the grains compared with the central portion of the metal film. The portion 116" (upper portion 116") from the upper surface 111" of the mask metal film 110" to the predetermined thickness and the portion 117" (lower portion 117") from the lower surface 112" to the predetermined thickness have different grain characteristics compared with the portion corresponding to the central portion 115" excluding the upper portion 116" and the lower portion 117". The upper portion 116" and the lower portion 117" are rolled so that the grains are arranged long in the rolling direction and have an irregular shape. The grains on the central portion 115" are generally non-directional and have a spherical morphology. Therefore, in order to prevent etching errors caused by different grain morphologies, it is preferable to consider performing a thickness reduction process on the upper portion 116" and the lower portion 117" of the mask metal film 110", and using the mask metal film 110 including the central portion 115" to manufacture the mask 100. If only the central portion 115" where the grains are irregular and uniform is etched and a mask pattern P is formed, there is an advantage in that the width of the mask pattern P can be finely controlled.

[0089] According to an embodiment of the present invention, based on the thickness of the mask metal film 110", when the upper surface is 0% and the lower surface is 100%, the central portion 115" can use at least a portion of 10% to 90% of the thickness portion. To put it another way, the thickness reduction produced by the surface defect removal process PS1 and the thickness reduction process PS2 described later can be carried out in about 10% to 90% of the overall thickness of the mask metal film 110", and when processes PS1 and PS2 are performed on both sides, the thickness of each surface can be reduced by about 5% to 45%. However, it is not necessarily limited to this. If the central portion 115" uses at least a portion of 10% to 90% of the thickness portion based on the thickness of the mask metal film 110", the degree of thickness reduction in each process PS1 and PS2 can be changed.

[0090] Furthermore, if Figure 3 As shown in (a), when performing the thickness reduction process of the mask metal film 110", defects existing on the surface can also be focused on.

[0091] Reference Figure 3 (b), the surface of the mask metal film 110' has scratch defects SD1 such as rolling scratches and dimples caused by pressing the metal film during the rolling process, and particle defects SD2 such as oxides and foreign substances such as SiO2 and Al2O3. These defects SD1 and SD2 will still be generated in the central portion 115" after the thickness reduction process of the mask metal film 110'.

[0092] like Figure 3 As shown in (c), when the thickness reduction process is performed by etching WE, a problem of etching according to the morphology of the scratch defect SD1 (SD1->SD1'->SD1") may occur. In addition, the particle defect SD2 may cause a problem of masking the etching WE or changing the etching ratio and only etching the periphery of the particle defect SD2 (SD2->SD2'->SD2"->SD2"'). In other words, the surface morphology of the scratch defect SD1 and the particle defect SD2 may be transferred to the central portion 115" as it is.

[0093] Therefore, the present invention is characterized in that after removing these surface defects SD1 and SD2, a thickness reduction process is performed to manufacture the mask metal film 110. Since the thickness reduction process is performed on the surface after removing the surface defects SD1 and SD2 and flattening, the surface still has the advantage of being homogenized and flattened after the thickness reduction.

[0094] Figure 4 FIG. 4 is a schematic diagram of a manufacturing process of a mask metal film according to an embodiment of the present invention.

[0095] Reference Figure 4 (a), a mask metal film 110' manufactured by a rolling process can be prepared. Surface defects SD1 and SD2 may exist on one side 111' (first side) or both sides 111', 112' (first side, second side) of the mask metal film 110'. The present invention may perform surface defect removal and thickness reduction processes on only one side 111', or may perform surface defect removal and thickness reduction processes on one side 111', and then perform surface defect removal and thickness reduction processes on the remaining other side 112' in sequence. However, for the sake of convenience of explanation, the following diagram illustrates the situation in which surface defects SD1 and SD2 are removed from both sides 111', 112' at the same time and the thickness is reduced on both sides at the same time.

[0096] Next, the surface defect removal process PS1 may be performed on the surfaces 111' and 112' of the mask metal film 110'. The surface defect removal process PS1 is to remove Figure 3 The process for the scratch defect SD1 and the particle defect SD2 described in .

[0097] The surface defect removal process PS1 can be performed by any of the methods of lapping, polishing, and buffing that can be used for fine surface treatment. The thickness of the mask metal film 110' can also be reduced by the surface defect removal process PS1. However, it is preferably performed on 2.5% to 12.5% ​​of the initial baseline thickness of the mask metal film. As an example, the thickness of the mask metal film 110' with a thickness of about 40μm can be reduced by about 1 to 5μm by the surface defect removal process PS1. This is because the surface defects SD1 and SD2 have a predetermined depth and the surface defect removal process PS1 at least makes the depth curve flatter. The flatter the surface, the smoother the surface will be during the process. Figure 3 The etching process described in (c) can prevent the problem of transfer based on surface morphology. In addition, the surface defect removal process PS1 has a slower thickness reduction speed than the etching thickness reduction process PS2 described later, so it is beneficial to process efficiency when processing relatively thin thickness.

[0098] Then, refer to Figure 4 (b), after the surface defect removal process PS1, the surface layers 113', 114' of a predetermined thickness can be reduced and removed from the surfaces 111', 112'. After the surface defect removal process PS1, the surface of the mask metal film 110'a has fewer defects and the surface becomes flatter. Fig.11 As described above, the depth of the scratch defect SD1 may be reduced, the plane shape may be changed from a lateral long strip to a nearly circular shape, and the particle defect SD2 may be removed.

[0099] Then, refer to Figure 4 (c), a thickness reduction process PS2 is performed. The thickness reduction of the thickness reduction process PS2 may be greater than the thickness reduction of the surface defect removal process PS1. In order to quickly reduce the thickness to a greater extent, the thickness reduction process PS2 may be performed by etching, in particular, by wet etching. Since the surface defects SD1 and SD2 of the mask metal film 110'a are removed, the thickness reduction may be performed along a homogeneous surface.

[0100] The thickness reduction process PS2 may be performed on the portions 116' and 117' corresponding to the predetermined thickness. Figure 3 The upper portion 116'' and the lower portion 117'' of the rolled Invar alloy described in (a) correspond to each other, and the portion has relatively irregular grains compared to the central portion 115'. As an example, the thickness of the mask metal film 110' with a thickness of about 40 μm can be reduced by about 15 to 34 μm.

[0101] Then, refer to Figure 4(d), after the thickness reduction process PS2 is performed, the portions 116' and 117' corresponding to the predetermined thickness may be reduced and removed. After the thickness reduction, the final thickness of the mask metal film 110 may be about 5 μm to 20 μm.

[0102] In addition, the surface defect removal process PS1 and the thickness reduction process PS2 may at least only be performed on the mask unit C portion of the mask metal film 110' [refer to Figure 2 ] is performed. That is, by performing the surface defect removal process PS1 and the thickness reduction process PS2 only on the mask unit C portion where the mask pattern P is to be formed, a fine mask pattern P can be formed in the subsequent process. In other words, in order to make the mask 100 described later well attached to the frame 200 based on welding [refer to Figure 7 ], the welding part WP may be formed with a thickness at least greater than the mask unit C. To this end, the surface defect removal process PS1 and the thickness reduction process PS2 may be performed only on the portion other than the welding part WP (or at least a portion of the dummy portion DM).

[0103] After the surface defect removal process PS1, an insulating portion such as a photoresist (not shown) is formed on the other portions except the mask unit C portion, and the mask unit C portion is subjected to a thickness reduction process PS2, so that a thickness difference can be generated with the mask unit C portion and the welding portion WP [or the dummy portion DM] and a step difference can be formed. Thus, the thickness of the other portions except the mask unit C portion or the welding portion WP portion can be about 5 μm to 20 μm, and the welding portion WP or the dummy portion DM portion can have a thicker thickness.

[0104] The mask metal film 110 of the present invention includes the central portion 115 ′ of the rolled metal film and thus has a regular grain morphology and a homogeneous surface without defects, so that in the process for forming the mask pattern P, a precision etching process can be performed.

[0105] Figure 5 is a schematic diagram of a process of manufacturing a mask metal film on a mask support template according to an embodiment of the present invention.

[0106] As an example, the surface defect removal process PS1 and the thickness reduction process PS2 of the mask metal film 110 may be performed on the support substrates 40 and 45. The support substrates 40 and 45 correspond to Figure 6 The template 50 described later can be replaced by the template 50. The advantages are that the mask pattern P can be formed immediately after the mask metal film 110 is formed on the template 50 to manufacture the mask 100, and the template 50 supporting the mask 100 can be moved onto the frame 200 to manufacture a frame-integrated mask immediately.

[0107] Reference Figure 5(a), the lower surface 112' (the second surface, i.e., the reverse surface of the first surface 111') of the mask metal film 110' can be bonded to the support substrate 40 by using the bonding portion 41. The bonding portion 41 can be made of the same material as the temporary bonding portion 55 described later, or any material having a certain adhesive force and being separable afterwards can be used without limitation.

[0108] After the mask metal film 110' is bonded to the support substrate 40, a surface defect removal process PS1 and a thickness reduction process PS2 may be performed on the upper surface 111' (first surface). After the surface defect removal process PS1, the surface layer 113' of the mask metal film 110" may be reduced and removed, and after the thickness reduction process PS2, the upper layer 116' may be reduced and removed.

[0109] The state of the support substrate 40, the adhesive portion 41 and the mask metal film 110'b can be directly determined by the following method. Figure 6 In this case, the support substrate 45 may correspond to the template 50, and the adhesive portion 45 may correspond to the temporary adhesive portion 55 described later. Even if the surface defects are removed and the thickness reduction process is performed on one side of the mask metal film 110' instead of both sides, the defective portion can be prevented from being transferred based on etching when the mask pattern P is formed. This is because the etching process flow for forming the mask pattern P is performed along the first side direction where the surface defects are removed. Figure 5 (b) to (d) further illustrate the situation where the process is performed on both sides.

[0110] Then, refer to Figure 5 (b), another support substrate 45 is prepared, and then the upper surface (first surface) of the mask metal film 110'b can be bonded to the support substrate 45 by using the bonding portion 46. The support substrate 45 and the bonding portion 45 can be the same as the support substrate 40 and the bonding portion 41. In addition, the support substrate 45 can correspond to the template 50 described later, and the bonding portion 45 can correspond to the temporary bonding portion 55 described later. In this case, Figure 5 Steps (b) to (d) can also be done by Figure 6 Step (b) is replaced.

[0111] Then, refer to Figure 5 (c), after the mask metal film 110'b is bonded to the support substrate 45, the support substrate 40 can be separated. Then, the surface defect removal process PS1 and the thickness reduction process PS2 are performed on the second surface 112". After the surface defect removal process PS1, the surface layer 114' of the mask metal film 110" can be reduced and removed, and after the thickness reduction process PS2, the lower layer 117' can be reduced and removed.

[0112] Then, refer to Figure 5(d) The manufacturing of the mask metal film 110 may be completed. The mask metal film 110 includes a central portion 115', and the thickness of the mask metal film 110 may be about 5 μm to 20 μm.

[0113] In addition, Figure 4 and Figure 5 It is assumed that the mask metal film 110 is made by a rolling process and is described here. Even in the case of a mask metal film manufactured by other processes such as electroforming, there may be characteristic differences between the grains in the surface part and the central part, so the same processes PS1 and PS2 can be used.

[0114] Figure 6 FIG. 1 is a schematic diagram of a process of forming a mask 100 by bonding a mask metal film 110 to a template 50 to manufacture a mask support template according to an embodiment of the present invention.

[0115] Figure 6 (a) A template 50 may be provided. The template 50 is a medium having the mask 100 attached to one side thereof and supporting the mask 100 to move the mask 100. The central portion 50a may correspond to the mask unit C of the mask metal film 110, and the edge portion 50b may correspond to the dummy portion DM of the mask metal film 110. In order to support the mask metal film 110 as a whole, the template 50 is a flat shape having an area greater than or equal to that of the mask metal film 110.

[0116] In order to facilitate visual observation during the process of aligning and bonding the mask 100 to the frame 200, the template 50 is preferably made of a transparent material. In addition, when the material is transparent, the laser can also pass through. As the transparent material, materials such as glass, silica, heat-resistant glass, quartz, aluminum oxide (Al2O3), borosilicate glass, and zirconium oxide can be used. As an example, the template 50 can be made of borosilicate glass, which has excellent heat resistance, chemical durability, mechanical strength, transparency, etc. 33 materials. In addition, The thermal expansion coefficient of 33 is about 3.3, which is slightly different from the thermal expansion coefficient of the invar alloy mask metal film 110 , and has the advantage of being easy to control the mask metal film 110 .

[0117] In addition, in order to prevent an air gap from being generated between the interface with the mask metal film 110 (or mask 100), the side of the template 50 that contacts the mask metal film 110 may be a mirror surface. Taking this into account, the surface roughness Ra of one side of the template 50 may be less than 100 nm. In order to achieve a template 50 with a surface roughness Ra of less than 100 nm, a wafer may be used for the template 50. The surface roughness Ra of the wafer is about 10 nm. There are a large number of products on the market and a large number of surface treatment processes, so it can be used as a template 50. The surface roughness Ra of the template 50 is at the nanometer level, so there is no or almost no air gap, and weld beads WB are easily generated by laser welding, so the alignment error of the mask pattern P may not be affected.

[0118] In order to allow the laser L irradiated from the upper part of the template 50 to reach the welding part WP (the area where welding is performed) of the mask 100, a laser through hole 51 may be formed on the template 50. The laser through hole 51 may be formed on the template 50 in a manner corresponding to the position and number of the welding part WP. Since a plurality of welding parts WP are arranged at predetermined intervals on the edge or dummy part DM of the mask 100, a plurality of laser through holes 51 may be formed at predetermined intervals corresponding thereto. As an example, since a plurality of welding parts WP are arranged at predetermined intervals on the dummy part DM on both sides (left / right) of the mask 100, a plurality of laser through holes 51 may be formed at predetermined intervals on both sides (left / right) of the template 50.

[0119] The position and number of the laser through holes 51 do not necessarily correspond to the position and number of the welding part WP. For example, the laser L may be irradiated only to a part of the laser through holes 51 to perform welding. In addition, the part of the laser through holes 51 that does not correspond to the welding part WP may also be used as an alignment mark when aligning the mask 100 and the template 50. If the material of the template 50 is transparent to the laser L, the laser through holes 51 may not be formed.

[0120] A temporary adhesive part 55 may be formed on one side of the template 50. Before the mask 100 is attached to the frame 200, the temporary adhesive part 55 allows the mask 100 (or the mask metal film 110') to be temporarily attached to one side of the template 50 and supported on the template 50.

[0121] The temporary adhesive portion 55 may use an adhesive or adhesive sheet that is removable by heating, or an adhesive or adhesive sheet that is removable by irradiating UV.

[0122] As an example, the temporary bonding portion 55 can use liquid wax. Liquid wax can use the same wax used in the polishing step of semiconductor wafers, etc., and its type is not particularly limited. As a resin component mainly used to control the adhesion, impact resistance, etc. related to the retention force, liquid wax may include substances and solvents such as acrylic acid, vinyl acetate, nylon and various polymers. As an example, the temporary bonding portion 55 can use SKYLIQUIDABR-4016 including acrylonitrile butadiene rubber (ABR, Acrylonitrile butadiene rubber) as a resin component and n-propyl alcohol as a solvent component. Liquid wax is formed on the temporary bonding portion 55 using a spin coating method.

[0123] The temporary adhesive part 55 as liquid wax has a lower viscosity at a temperature higher than 85° C. to 100° C., and increases viscosity at a temperature lower than 85° C., and is partially cured into a solid, thereby fixing and bonding the mask metal film 110 ′ to the template 50 .

[0124] Secondly, refer to Figure 6 (b), the mask metal film 110 may be bonded to the template 50. The liquid wax may be heated to above 85°C, and the mask metal film 110 may be brought into contact with the template 50, and then the mask metal film 110 and the template 50 may be passed between rollers for bonding.

[0125] According to one embodiment, the template 50 is baked at about 120° C. for 60 seconds to vaporize the solvent of the temporary adhesive portion 55, and then the mask metal film lamination process can be performed immediately. The lamination is performed by loading the mask metal film 110 on the template 50 having the temporary adhesive portion 55 formed on one side and passing it between an upper roller at about 100° C. and a lower roller at about 0° C. As a result, the mask metal film 110' can be in contact with the template 50 by sandwiching the temporary adhesive portion 55.

[0126] As another example, the temporary adhesive portion 55 may use a thermal release tape. The thermal release tape is a base film with a PET film or the like arranged in the middle, and thermally separable adhesive layers (thermal release adhesive) are arranged on both sides of the base film, and a separation film / release film may be arranged on the outer contour of the adhesive layer. The separation temperatures of the adhesive layers arranged on both sides of the base film may be different from each other.

[0127] According to one embodiment, when the separation film / release film is removed, the lower surface of the thermal separation tape [the lower second adhesive layer of the base film] is bonded to the template 50, and the upper surface of the thermal separation tape [the upper first adhesive layer of the base film] can be bonded to the mask metal film 110'. The separation temperatures of the first adhesive layer and the second adhesive layer are different from each other, so in the following description Fig.16 In the embodiment, when the template 50 is separated from the mask 100 , the mask 100 can be separated from the template 50 and the temporary adhesive portion 55 by heating the first adhesive layer.

[0128] Alternatively, you can use the Figure 4 The mask metal film 110 of the processes PS1 and PS2. Or, Figure 6 (b) can be replaced by Figure 5 The state after the mask metal film 110' is bonded to the support substrate 40 (corresponding to the template 50) in step (a) and processes PS1 and PS2 are performed on one side. In addition, Figure 6 (b) can be replaced by Figure 5 (a) to (d) are the states in which the mask metal film 110' is bonded to the supporting substrate 40 (corresponding to the template) and processes PS1 and PS2 are performed on one side, and the mask metal film 110'b is bonded to the supporting substrate 45 (corresponding to the second) and processes PS1 and PS2 are performed on the other side.

[0129] In addition, the Figure 4 , Figure 5 The thickness reduction process PS2 can only be performed on the mask unit C portion. After the surface defect removal process PS1, an insulating portion such as a photoresist is formed only in the area corresponding to the welding portion WP of the mask metal film 110' (not shown), or, after the mask metal film 110' is bonded and supported on the template 50, an insulating portion such as a photoresist is formed only in the area corresponding to the welding portion WP of the mask metal film 110' (not shown), the process PS2 is performed on the mask unit C portion, so that the welding portion WP is formed with a thicker thickness and forms a step difference with the mask unit C portion, and at the same time, the surface of the mask unit C portion where the mask pattern P is to be formed can be made into a defect-free state.

[0130] In addition, the lower surface of the mask metal film 110 may further form an insulating portion such as a photoresist (not shown), or the insulating portion may be sandwiched between the mask metal film 110 and the temporary bonding portion 55 for bonding. Figure 6In step (c), in order to prevent the etching liquid from penetrating into the interface between the mask metal film 110 and the temporary bonding part 55 to damage the temporary bonding part 55 / template 50 and generate etching errors of the mask pattern P, an insulating part is further formed. In order to have strong durability against the etching liquid, the insulating part may include at least one of a curable negative photoresist and a negative photoresist containing epoxy resin. As an example, preferably, by using SU-8 photoresist based on epoxy resin, a black matrix photoresist (black matrix) is formed during the baking of the temporary bonding part 55 and the baking of the insulating part 25 (refer to Figure 6 (c)) and other processes are solidified together.

[0131] Then, refer to Figure 6 (c) , the patterned insulating portion 25 may be formed on the mask metal film 110. The insulating portion 25 may be formed of a photoresist material by a printing method or the like.

[0132] Next, the mask metal film 110 may be etched. Dry etching, wet etching, or the like may be used without limitation, and as a result of the etching, the portion of the mask metal film 110 exposed by the empty space 26 between the insulating portions 25 may be etched away. The etched portion of the mask metal film 110 forms a mask pattern P, and thus a mask 100 having a plurality of mask patterns P formed therein may be manufactured.

[0133] At this time, the mask metal film 110 is in a state where surface defects have been removed, so it can be etched in a desired pattern form in the etching process. A fine mask pattern P can be formed, so there is an effect that the mask 100 that can be used in a high-resolution OLED pixel process can be manufactured.

[0134] Then, refer to Figure 6 (d) The manufacturing of the template 50 supporting the mask 100 can be completed by removing the insulating portion 25 .

[0135] In addition, replace Figure 6 In steps (b) and (c), the mask 100 having a plurality of mask patterns P formed on the mask metal film 110 is directly bonded to the template 50 with a temporary bonding portion 55 interposed therebetween, thereby manufacturing the template 50 for supporting the mask 100d.

[0136] Figure 7 1 is a schematic diagram showing a state in which the template 50 is loaded on the frame 200 and the mask 100 is aligned with the unit region CR of the frame 200 according to an embodiment of the present invention. Figure 7 , a method of corresponding / attaching one mask 100 to the unit region CR is listed, and a plurality of masks 100 may be simultaneously corresponding to all unit regions CR and the masks 100 may be attached to the frame 200. In this case, a plurality of templates 50 may be provided to support the plurality of masks 100 respectively.

[0137] The template 50 can be transferred by the vacuum suction cup 90. The vacuum suction cup 90 can be used to suck the opposite side of the template 50 to which the mask 100 is bonded and transferred. After the vacuum suction cup 90 sucks the template 50 and turns it over, the bonding state and alignment state of the mask 100 are not affected during the process of transferring the template 50 to the frame 200.

[0138] Next refer to Figure 7 , the mask 100 can be matched to a mask unit region CR of the frame 200. The mask 100 can be matched to the mask unit region CR by loading the template 50 on the frame 200 [or the mask unit sheet portion 220]. While controlling the position of the template 50 / vacuum suction cup 90, it is possible to observe through a microscope whether the mask 100 corresponds to the mask unit region CR. Since the template 50 presses the mask 100, the mask 100 can be closely attached to the frame 200.

[0139] In addition, a lower support body 70 may be further disposed below the frame 200. The lower support body 70 may press the reverse side of the mask unit region CR in contact with the mask 100. At the same time, since the lower support body 70 and the template 50 press the edge of the mask 100 and the frame 200 [or the mask unit sheet portion 220] in opposite directions to each other, the alignment state of the mask 100 can be maintained and not disturbed.

[0140] Next, laser L is irradiated to the mask 100 and the mask 100 is attached to the frame 200 by laser welding. Welding beads WB are generated on the welding part WP of the mask by laser welding, and the welding beads WB may have the same material as the mask 100 / frame 200 and be integrally connected with them.

[0141] Figure 8 FIG. 2 is a schematic diagram of a process of separating the mask from the template after attaching the mask to the frame according to an embodiment of the present invention.

[0142] Reference Figure 8After the mask 100 is attached to the frame 200, the mask 100 and the template 50 can be separated (debonding). The separation of the mask 100 and the template 50 can be performed by heating the temporary adhesive portion 55, chemically treating the temporary adhesive portion 55, applying ultrasonic waves, and applying ultraviolet rays. Since the mask 100 remains attached to the frame 200, only the template 50 can be lifted. As an example, if a heat ET higher than a temperature of 85°C-100°C is applied, the viscosity of the temporary adhesive portion 55 is reduced, and the adhesive force between the mask 100 and the template 50 is weakened, so that the mask 100 and the template 50 can be separated. As another example, the temporary adhesive portion 55 can be separated from the template 50 by immersing the temporary adhesive portion 55 in a chemical substance such as IPA, acetone, ethanol, etc., so that the temporary adhesive portion 55 is dissolved, removed, etc. As another example, the adhesive force between the mask 100 and the template 50 is weakened by applying ultrasonic waves US or ultraviolet rays UV, so that the mask 100 and the template 50 can be separated.

[0143] Fig. 9 2 is a schematic diagram of a state where the mask 100 is attached to the frame 200 according to an embodiment of the present invention. Fig.14 2 shows a state where all the masks 100 are attached to the unit region CR of the frame 200. Although the masks 100 may be attached one by one and then the templates 50 may be separated, all the masks 100 may be attached and then all the templates 50 may be separated.

[0144] The template 50 is separated from the mask 100 by the vacuum chuck 90, and the first insulating portion 23 will remain on the mask 100. If the first insulating portion 23 is a curable photoresist, it is not easy to remove it by a wet etching process. Therefore, in order to remove the first insulating portion 23 on the mask 100, at least one of plasma PS and ultraviolet UV can be applied. After loading the frame-integrated mask 100, 200 into another chamber (not shown), a process can be performed in which atmospheric pressure plasma or vacuum plasma PS or ultraviolet UV is applied to remove only the first insulating portion 23.

[0145] Fig. 9 FIG. 1 is a schematic diagram of a state where the mask 100 is attached to the frame 200 according to an embodiment of the present invention.

[0146] Reference Fig. 9, one mask 100 can be bonded to one unit region CR of the frame 200. Since the thickness of the mask unit sheet portion 220 of the frame 200 is thin, if the mask 100 is bonded to the mask unit sheet portion 220 in a state where a tensile force is applied, the tensile force remaining in the mask 100 will act on the mask unit sheet portion 220 and the mask unit region CR, thereby deforming them. Therefore, the mask 100 should be bonded to the mask unit sheet portion 220 without applying a tensile force to the mask 100. The present invention can complete the process of corresponding the mask 100 to the mask unit region CR of the frame 200 by only attaching the mask 100 to the template 50 and loading the template 50 on the frame 200, and this process does not apply any tensile force to the mask 100.

[0147] Since only one unit C of the mask 100 needs to be matched and the alignment status needs to be confirmed, the present invention can significantly shorten the manufacturing time compared with the existing method that simultaneously matches multiple units C (C1-C6) and needs to confirm all alignment statuses.

[0148] In addition, Figure 6 In (b), as described above, when the mask metal film 110 is bonded to the template 50 by the lamination process, a temperature of about 100° C. is applied to the mask metal film 110. Thus, the mask metal film 110 is bonded to the template 50 with a partial tensile force applied thereto. Then, if the mask 100 is attached to the frame 200 and the template 50 is separated from the mask 100, the mask 100 may shrink by a certain amount.

[0149] If the template 50 is separated from the mask 100 after each mask 100 is attached to the corresponding mask unit region CR, since the multiple masks 100 apply tensions that shrink in opposite directions, the tensions cancel each other out, so that no deformation occurs on the mask unit sheet portion 220. For example, on the first grid sheet portion 223 between the mask 100 attached to the CR11 unit region and the mask 100 attached to the CR12 unit region, the tension acting in the right direction of the mask 100 attached to the CR11 unit region and the tension acting in the left direction of the mask 100 attached to the CR12 unit region can cancel each other out. Therefore, the deformation of the frame 200 (or the mask unit sheet portion 220) due to the tension is minimized, thereby having the advantage of minimizing the alignment error of the mask 100 (or the mask pattern P).

[0150] Next, we will use an experimental example to understand Figure 4 The surface defect removal process PS1 described in detail in the present invention is used to remove the surface defects SD1 and SD2.

[0151] Fig.10Surface photographs of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention. Fig.10 (a) and (c) and (b) and (d) show the same area before and after the process.

[0152] According to an experimental example, a surface defect removal process PS1 is performed on a rolled Invar metal film having a thickness of 40 μm by buffing with a thickness of 2 μm.

[0153] like Fig.10 As shown in (a) and (b), the surface of the mask metal film has a scratch defect SD1 such as a rolling scratch generated when the metal film is pushed during rolling. Considering that the rolling direction is the x-axis direction, it can be confirmed that (a) is a long and thin scratch defect SD1 of more than 100 μm, (b) is a long and thin scratch defect SD1 of more than 10 μm, and a particle defect SD2 of oxides such as SiO2 and Al2O3 and foreign substances is formed in the scratch defect SD1.

[0154] Reference Fig.10 (c) shows that the scratch defect SD1 has been removed. Although the scratch defect SD1 is a thin and long one with a length of more than 100 μm, the defect can be removed because the depth of the defect is less than 2 μm.

[0155] In addition, refer to Fig.10 (d) It can be confirmed that the shape of the elongated scratch defect SD1 has become quasi-circular and the particle defect SD2 has been removed. That is, the size of the scratch defect SD1 has been reduced and the particle defect SD2 has been removed. However, according to the size of the particle defect SD2 placed on the scratch defect SD1, it can be confirmed that the shape of the elongated scratch defect SD1 has become very thin and quasi-circular. The depth is very shallow and has a circular diffusion shape, so even if etching for forming the mask pattern P is performed, the small curvature shape of the defect can maintain uniform flatness. Finally, even if the defect shape shifts during the etching process, no error will occur or it can be ignored.

[0156] The table below shows the number and size of defects before and after the surface defect removal process PS1. Defects were confirmed in an area of ​​100mmX100mm for 9 samples.

[0157] [Table 1]

[0158] Sample Number of defects before process Number of defects after process 1 1 0 2 3 3 3 14 8 4 15 4 5 17 10 6 7 7 7 8 8 8 1 0 9 1 0 total 67 39

[0159] [Table 2]

[0160] Defect size percentile Defect size before process (μm) Defect size after process (μm) MAX (100%) 373.3 20.9 75％ 25.6 11.1 MEDIAN (50%) 17.7 10.6 25％ 12.8 7.1 MIN(0%) 5.7 4.5 average 56.7 10.3

[0161] As shown in Table 1, defects were removed / reduced in all 9 samples after the process. All defects were removed in samples 1, 8, and 9. Samples 2 to 7 showed that the number of defects remained the same or decreased and these defects coexisted with the scratch defect SD1 and the particle defect SD2. In addition, it was confirmed that the shape of the scratch defect SD1 changed from an elongated shape to a round shape.

[0162] As can be seen from Table 2, the size of the defect is reduced. In other words, it can be confirmed that the size of the elongated scratch defect SD1 in Samples 2 to 7 is reduced and the shape is changed to a round shape.

[0163] The elongated scratch defect SD1 is a defect in which the horizontal length is greater than the vertical length on the plane. That is, the x-axis length:y-axis length is k:l (k, l are positive numbers), and k can be greater than l. After process PS1, the defect becomes circular, the x-axis length:y-axis length is m:n (m, n are positive numbers), and k / l>m / n. That is, at least the horizontal length is reduced and the vertical length is increased, resulting in a smaller defect.

[0164] Therefore, the mask metal film 110 of the present invention may have a circular or quasi-circular defect on the surface. Alternatively, the elongated scratch defect SD1 may also remain as a substantially elliptical defect as the frame becomes rounded.

[0165] The defect SD1 may become a flatter shape as the curvature decreases. As the defect SD1 becomes circular, the curvature of the edge of the defect SD1 may become smaller, and the depth of the defect may become smaller, so that it may become flat. At this time, when observing the flattened defect, the angle formed by the side of the defect and the xy plane (or the surface of the mask metal film 110) may be 0° to 30°. If the angle is 0°, it means that it is consistent with the surface of the mask metal film 110 without bending in the depth direction. When the processes PS1 and PS2 of the mask metal film 110 are completed and the mask pattern P is formed, the side of the mask pattern P may form an inverted cone with an angle of about 45° to 70° with the xy plane (or the surface of the mask metal film 110). Therefore, considering the angle of the mask pattern P, if the side angle of the defect is close to the angle of the mask pattern P, it may occur that before the mask pattern P is formed, the surface defect of the mask metal film 110 remains in a form similar to the mask pattern P, so the side angle of the defect should be sufficiently smaller than the angle of the mask pattern P.

[0166] Fig.11 Surface optical microscope photographs of a defective sample of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention. Fig.11 These are photos of four identifiable defects (#1 to #4) extracted from one sample.

[0167] Reference Fig.11As can be seen from (a), all of #1 to #4 are elongated defects. In particular, it can be confirmed that the defect indicated by the dotted circle is a defect in which the particle defect SD2 is included in the scratch defect SD1.

[0168] Reference Fig.11 As shown in (b), after process PS1, most of the defects except the defects indicated by dotted circles in #1 to #4 have been removed. In #1, #3, and #4, it can be confirmed that the elongated scratch defect SD1 including the particle defect SD2 has become round. In addition, after process PS1, it can be confirmed that the depth of the defect has also become smaller as the depth of the color has become lighter.

[0169] Fig.12 The following are surface AFM (Atomic Force Microscope) photos of a defective sample of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention.

[0170] Reference Fig.12 It can be easily found that the surface of the mask metal film becomes more homogeneous after process PS1. Fig.12 (a) shows the light and dark of the horizontal stripes. Each part of the surface shows a large height difference. On the contrary, Fig.12 In (b), except for the dotted circle, the light and dark are gradually changed, and the height of the surface is relatively flat. In addition, after the process PS1, the color depth of the dotted circle becomes lighter, and it can be confirmed that the depth of the defect is also reduced.

[0171] Figures 13 to 16 The optical microscope photographs at various magnifications are taken of a surface defect removal process of a defective sample of a mask metal film according to an experimental example before and after the process. Fig.13 , Fig.14 , Fig.15 and Fig.16 The following are photos of defects #1, #2, #3, and #4 magnified 50 times, 200 times, 500 times, and 1000 times, respectively. The zigzag thick lines around the dotted circle are randomly marked on the surface to facilitate the observation of defects.

[0172] Reference Fig.13 , 15 16, it can be confirmed that defects #1, #3, and #4 are all elongated defects. In particular, it can be confirmed that the defect represented by the dotted circle is a defect in which the scratch defect SD1 also includes the particle defect SD2. In addition, it can be confirmed that the elongated scratch defect SD1 including the particle defect SD2 has become round. After the process PS1, the color depth has become lighter, and it can be confirmed that the depth of the defect has also become smaller.

[0173] Reference Fig.14It can be seen that defect #2 is also a long and narrow defect. In particular, it can be confirmed that the defect represented by the dotted circle is a defect in which the scratch defect SD1 also contains the particle defect SD2. However, defect #2 is shown to be removed after process PS1. This can be understood as the depth of the particle defect SD2 in process PS1 is shallow or the particle defect SD2 is initially detached and presents a non-circular shape and the defect is removed.

[0174] The following table shows the Figures 13 to 16 Determined defect size after surface defect removal process PS1.

[0175] [Table 3]

[0176]

[0177]

[0178] Referring to Table 3, it can be seen that particle defects SD2 of all four defects were removed after process PS1. In addition, it can be confirmed that the x-axis length decreased at an increase and decrease rate of -45.5%, -25.2%, -4.8%, and -14.8%, and the y-axis length increased at an increase and decrease rate of 45.1%, 13.2%, 36.2%, and 15.0%. It can be seen that the shape of the defect changed from elongated to round.

[0179] In addition, the ratios of the x-axis length to the y-axis length of the four defects after process PS1 are approximately 1.41:1, 1.30:1, 2.49:1, and 2.47:1. Defects SD1 and SD20 that exceeded 3:1 before process PS1 became circular or nearly elliptical with a ratio of x-axis length to y-axis length of 1:1 to 3:1 after process PS1. It can be confirmed that the x-axis length or y-axis length of the defect is less than 30μm.

[0180] As described above, the present invention has the effect of maintaining a homogeneous surface state without defects by performing a surface defect reduction process of the mask metal film. Next, in order to maintain a homogeneous surface state after performing the thickness reduction process, a fine mask pattern P can be formed in the etching process for forming the mask pattern P.

[0181] As described above, the present invention lists preferred embodiments for illustration and description, but the present invention is not limited to the above embodiments, and those skilled in the art can make various modifications and changes without departing from the spirit of the present invention. Such modifications and changes all belong to the scope of the present invention and the appended claims.

Claims

1. A mask metal film support template, which is used to support a mask metal film used in manufacturing an OLED pixel formation mask and correspond it to a frame, wherein: The mask metal film support template comprises: template; a temporary adhesive portion formed on the template; and A mask metal film is bonded to the template by sandwiching a temporary bonding portion, The mask metal film is manufactured by sequentially performing surface defect removal and thickness reduction processes on at least one surface of a metal film having scratch defects generated in a rolling process. The surface defect removal process is carried out by any of the methods of grinding, polishing and lapping. After the surface defect removal process and the thickness reduction process, the size of the scratch defect is reduced to a ratio of x-axis length:y-axis length of 1:1 to 3:1, wherein the x-axis is parallel to the rolling direction.

2. The mask metal film support template according to claim 1, wherein: A state where no particles exist within a scratch defect.

3. The mask metal film support template according to claim 1, wherein: The angle formed by the side surface of the scratch defect and the xy plane is 0° to 30°.

4. The mask metal film support template according to claim 1, wherein: The width of the scratch defect is greater than 0 and less than 30 μm.

5. The mask metal film support template according to claim 1, wherein: The mask metal film has a thickness of 5 μm to 20 μm.

6. The mask metal film support template according to claim 5, wherein: The surface defect removal process is performed on 2.5% to 12.5% ​​of the base thickness of the metal film, so that the ratio of the x-axis length:y-axis length of the scratch defect changes from k:l to m:n, Among them, k and l are positive numbers, k is a number greater than 1, m and n are positive numbers, and k / l>m / n.

7. The mask metal film support template according to claim 5, wherein: The thickness reduction process is performed by wet etching.

8. The mask metal film support template according to claim 1, wherein: The mask metal film includes a mask unit region as a region for forming a mask pattern and a dummy region around the mask unit region. The thickness of a portion of the dummy portion region corresponding to the soldering portion is at least greater than the thickness of the remaining region.

9. The mask metal film support template according to claim 1, wherein: Based on the thickness of the metal film produced by the rolling process, when the upper surface is 0% and the lower surface is 100%, the mask metal film uses at least a portion corresponding to 10% to 90% of the thickness of the metal film.

10. A method for manufacturing a mask metal film support template, wherein the mask metal film support template is used to support a mask metal film for forming OLED pixels and correspond it to a frame, wherein: The method comprises the following steps: (a) bonding a metal film manufactured by a rolling process to a template having a temporary bonding portion formed on one side; (b) removing surface defects and reducing thickness on the first side of the metal film; (c) reducing the thickness of the first surface of the metal film by etching to produce a template that adheres to and supports the mask metal film, The metal film in step (a) has a scratch defect on at least one surface caused by a rolling process, The surface defect removal process in step (b) is carried out by any method of grinding, polishing or lapping. The size of the scratch defect after step (b) and step (c) is reduced to a ratio of x-axis length:y-axis length of 1:1 to 3:1, wherein the x-axis is parallel to the rolling direction.

11. The method for manufacturing a mask metal film support template according to claim 10, wherein: Step (a) comprises the following steps: (a1) forming an insulating portion on a second surface of the metal film which is the opposite surface of the first surface; (a2) A metal film is bonded to the upper surface of a template having a temporary bonding portion formed on one surface thereof by interposing an insulating portion.

12. The method for manufacturing a mask metal film support template according to claim 10, wherein: Further comprising the steps of: (d) separating the mask metal film from the template; (e) bonding the first surface of the mask metal film to a second template having a temporary bonding portion formed on one surface; (f) removing surface defects and reducing thickness on the second surface of the mask metal film, which is the reverse side of the first surface; (g) The thickness of the second surface of the mask metal film is reduced by etching.

13. The method for manufacturing a mask metal film support template according to claim 10, wherein: The thickness reduction in step (b) is performed with respect to 2.5% to 12.5% ​​of the initial base thickness of the metal film.

14. The method for manufacturing a mask metal film support template according to claim 13, wherein: The thickness reduction in step (c) is performed at a greater amount than the thickness reduction in step (b).

15. The method for manufacturing a mask metal film support template according to claim 14, wherein: Step (c) is performed by wet etching.

16. The method for manufacturing a mask metal film support template according to claim 14, wherein: After step (c), the thickness of the mask metal film is 5 μm to 20 μm.

17. The method for manufacturing a mask metal film support template according to claim 10, wherein: After step (b), the defect morphology on the first surface of the metal film, i.e., the ratio of the x-axis length: the y-axis length, changes from k:l to m:n. Among them, k and l are positive numbers, k is a number greater than 1, m and n are positive numbers, and k / l>m / n.

18. The method for manufacturing a mask metal film support template according to claim 10, wherein: After step (b), particles included in the defects on the first side of the metal film are removed.

19. The method for manufacturing a mask metal film support template according to claim 10, wherein: After step (b), an insulating portion is formed on a region remaining except for the mask unit portion of the metal film or on a soldering portion region of the metal film, and step (c) is performed on a region where the insulating portion is not formed.

20. The method for manufacturing a mask metal film support template according to claim 10, wherein: Further comprising the steps of: (d) A mask is manufactured by forming a mask pattern on a mask metal film.

21. A method for manufacturing a mask support template, wherein the mask support template is used to support a mask for forming OLED pixels and correspond it to a frame, the method comprising the following steps: (a) preparing a metal film manufactured by a rolling process; (b) removing surface defects and reducing thickness on the first side of the metal film; (c) reducing the thickness of the first surface of the metal film by etching to produce a mask metal film; (d) manufacturing a mask by forming a mask pattern on a mask metal film; as well as (e) bonding the mask to a template having a temporary bonding portion formed on one side, The metal film in step (a) has a scratch defect on at least one surface caused by a rolling process, The surface defect removal process in step (b) is carried out by any method of grinding, polishing or lapping. The size of the scratch defect after step (b) and step (c) is reduced to a ratio of x-axis length:y-axis length of 1:1 to 3:1, wherein the x-axis is parallel to the rolling direction.

22. A mask metal film for manufacturing a mask for forming OLED pixels, wherein: The mask metal film is manufactured by sequentially performing surface defect removal and thickness reduction processes on at least one surface of a metal film having scratch defects generated in a rolling process. The surface defect removal process is carried out by any of the methods of grinding, polishing and lapping. After the surface defect removal process and the thickness reduction process, the size of the scratch defect is reduced to a ratio of x-axis length:y-axis length of 1:1 to 3:1, wherein the x-axis is parallel to the rolling direction.

23. A method for manufacturing a mask metal film, comprising the following steps: (a) preparing a metal film manufactured by a rolling process; (b) removing surface defects and reducing thickness on the first side of the metal film; as well as (c) reducing the thickness of the first surface of the metal film by etching to produce a mask metal film, The metal film in step (a) has a scratch defect generated during the rolling process on at least one surface, The surface defect removal process in step (b) is carried out by any method of grinding, polishing or lapping. The size of the scratch defect after step (b) and step (c) is reduced to a ratio of x-axis length:y-axis length of 1:1 to 3:1, wherein the x-axis is parallel to the rolling direction.

24. A method for manufacturing a frame-integrated mask, wherein the frame-integrated mask is integrally formed by at least one mask and a frame for supporting the mask, wherein: The method comprises the following steps: (a) loading the mask support template manufactured by the method of claim 21 onto a frame having at least one mask unit area so that the mask corresponds to the mask unit area of ​​the frame; (b) Attach the mask to the frame.

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