TWI770929B - Mask metal sheet and template for supporting mask metal sheet and template for supporting mask and producing method thereof - Google Patents

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 according to the present invention is used for manufacturing a mask for OLED pixel formation, and is characterized in that it includes at least a central portion of a metal sheet manufactured by a rolling process, and at least one surface includes a circle or a Axis length: y-axis length ratio is 1:1 to 3:1 for elliptical defects.

Description

Mask metal film, mask metal film support template, mask support template and manufacturing method thereof Field of Invention

The present invention relates to a mask metal film, a mask metal film supporting template, a mask supporting template and a manufacturing method thereof. More specifically, it relates to a method for forming a fine mask pattern on a mask, so that the mask can be supported and moved stably without deformation, and can accurately align the masks on the frame. A mask metal film, a mask metal film support template, a mask support template and a manufacturing method thereof.

Background of the Invention

As a technology for forming pixels in the OLED manufacturing process, the FMM (Fine Metal Mask) method is mainly used, which attaches a metal mask (Shadow Mask) in the form of a thin film to the substrate and is required to deposition of organic matter on the site.

A conventional mask manufacturing method is produced by preparing a metal sheet used as a mask, performing patterning after PR coating on the metal sheet, or performing PR coating to form a pattern, and then manufacturing by etching Mask with pattern. In ultra-high-definition OLED, the existing QHD picture quality is 500-600PPI (pixel per inch, pixels per inch), and the pixel size reaches about 30-50μm, while 4KUHD and 8KUHD high-definition have higher ~860PPI, ~ 1600PPI and other resolutions. Therefore, there is a need to develop a technique capable of precisely adjusting the size of the mask pattern.

In addition, in the existing OLED manufacturing process, after the mask is manufactured into a strip shape, a plate shape, etc., Solder the mask to the OLED pixel deposition frame and use. To fabricate large area OLEDs, a plurality of masks can be fastened to the OLED pixel deposition frame, during which each mask is stretched to make it flat. Adjusting the stretching force to flatten the entire portion of the mask is a very difficult task. In the process of fixing a plurality of masks on a frame, there is still a problem of poor alignment between masks and between mask units. In addition, in the process of welding and fixing the mask to the frame, the thickness of the mask film is too thin and the area is large, so there is a problem that the mask sags or twists due to the load.

In this way, considering the pixel size of ultra-high-definition OLEDs, it is necessary to reduce the alignment error between each unit to about a few μm. Exceeding this error will lead to defective products, so the yield may be extremely low. Therefore, it is necessary to develop a technique for preventing deformation such as sagging or twisting of the mask and for accurate alignment, a technique for fixing the mask to the frame, and the like.

Therefore, the present invention has been made in order to solve various problems of the prior art as described above, and an object of the present invention is to provide a mask metal film, a mask metal film support template, and a mask support capable of forming a fine mask pattern on a mask Template and method of manufacture.

Moreover, the objective of this invention is to provide the manufacturing method of the frame-integrated mask which can prevent deformation|transformation, such as a sagging and a twist of a mask, and can align it correctly.

The above objects of the present invention are achieved by a mask metal film support template for supporting and corresponding to a frame of a mask metal film used in manufacturing a mask for OLED pixel formation, the template comprising: : a template; a temporary adhesive portion, which is formed on the template; and a mask metal film, which is bonded to the template by sandwiching the temporary adhesive portion, the mask metal film including at least the central portion of the metal film manufactured by the rolling process, At least one surface includes circular or elliptical defects with a ratio of x-axis length:y-axis length of 1:1 to 3:1.

The mask metal film may be in a state in which particles do not exist in circular or elliptical defects.

The angle that can be formed between the side surface of the defect of the mask metal film and the xy plane is 0° to 30°.

The width of the defects of the mask metal film may be less than 30 μm (over 0).

The x-axis can be parallel to the rolling direction.

The mask metal film may have a thickness of 5 μm to 20 μm 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 surface defect removal process is performed on 2.5% to 12.5% of the initial reference thickness of the mask metal film, so that the shape of the defect, that is, the ratio of the x-axis length: the y-axis length is k: l [k, l are positive numbers, and k is greater than l The number of ] becomes m:n [m, n are positive numbers], and k/l>m/n can be satisfied.

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

The mask metal film includes a mask cell region as a region for forming a mask pattern and a dummy portion region around the mask cell region, and the thickness of the portion corresponding to the welding portion in the dummy portion region may be at least greater than that of the remaining regions.

Based on the thickness of the mask metal film produced by the rolling process, when the upper surface is 0% and the lower surface is 100%, use at least 10% to 90% of the thickness of the mask metal film in the central part. part.

In addition, the above-mentioned objects of the present invention are achieved by a method for manufacturing a mask supporting template for supporting and corresponding to a mask for OLED pixel formation, the method comprising the steps of: (a) applying The mask metal film produced by the rolling process is bonded to a template with a temporary bonding portion formed on one side; (b) the surface defects are removed and the thickness is reduced on the first side of the mask metal film; (c) the mask metal film is The thickness of the first side is reduced by etching.

The step (a) may include the following steps: (a1) forming an insulating part on the opposite side of the first surface of the mask metal film, that is, on the second surface; (a2) interposing the insulating part on the template on which the temporary adhesive part is formed on one side Will The mask metal film is bonded to the upper face of the template.

It may further include the following steps: (d) separating the mask metal film from the template; (e) adhering the first side of the mask metal film to the second template with the temporary bonding portion formed on one side; (f) attaching the mask metal film to the second template. The opposite side of the first side of the mask metal film, that is, the second side, removes surface defects and reduces the thickness; (g) reduces the thickness by etching on the second side of the mask metal film.

The thickness reduction of step (b) may be performed for 2.5% to 12.5% of the initial reference thickness of the mask metal film.

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

The thickness reduction of step (c) may be performed by a greater amount than the thickness reduction of step (b).

Step (c) may be performed by wet etching.

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

After step (b), the defect morphology on the first surface, that is, the ratio of x-axis length:y-axis length is changed from k:l[k, l is a positive number, k is a number greater than l] to m:n[m , n is a positive number], and can satisfy k/l>m/n.

After step (b), particles included in the defects on the first face can be removed.

After the step (b), an insulating portion is formed on the region remaining except the mask cell portion of the mask metal film or on the solder portion region of the mask metal film, and step ( c).

In addition, the above-mentioned objects of the present invention are achieved by a method for manufacturing a mask support template for supporting and corresponding to a mask for OLED pixel formation to a frame, the method comprising the steps of: (a) applying The mask metal film produced by the rolling process is bonded to a template with a temporary bonding portion formed on one side; (b) the surface defects are removed and the thickness is reduced on the first side of the mask metal film; (c) the mask metal film is The first side of the mold metal film is reduced in thickness by etching; and (d) a mask is fabricated by forming a mask pattern on the mask metal film.

Furthermore, the above objects of the present invention are achieved by a method of manufacturing a mask supporting template for supporting and corresponding to a frame for OLED pixel formation masks, the method comprising the following ccc(a) preparation for rolling (b) remove the ccc trap on the first side of the mask metal film and reduce the thickness; (c) reduce the thickness by etching on the first side of the mask metal film; (d) A mask is fabricated by forming a mask pattern on a cc-mold metal film; and (e) adhering the mask to a template having a side-ccc portion formed thereon.

In addition, the above-mentioned object of the present invention is achieved by a mask metal film, which is used to manufacture a mask for OLED ccc, at least including the central portion of the metal sheet manufactured by a rolling process, and the ccc surface includes a Circular or elliptical defects c with a ratio of x-axis length:y-axis length from 1:1 to 3:1

In addition, the above-mentioned objects of the present invention are achieved by a method for manufacturing a mask metal film, the method including the ccc steps: (a) preparing a mask metal film (sheet) manufactured by a rolling process; removing surface defects and reducing the thickness on the first side of the mask gold ccc; and (c) reducing the thickness through the ccc on the first side of the mask metal film.

Furthermore, the above objects of the present invention are achieved by a method for manufacturing a mask metal film, the frame ccc mask is integrally formed with at least one mask and a frame for supporting the mask, wherein the method includes the ccc step: (a ) loading a mask support template manufactured by the described method onto a frame having at least one mask ccc domain so that the mask corresponds to the mask cell area of the frame; (b) attaching the mask to the frame ccc

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

Further, according to the present invention, there is an effect that deformation such as sagging or twisting of the mask can be prevented and it can be accurately aligned.

40,45: Support substrate

41,46: Adhesive

50: Template (template)

51: Laser through hole

55: Temporary bonding part

100: Mask

110, 110', 110": mask film, mask metal film

111': The first side of the mask metal film

112': the second side of the mask metal film

113': The first surface layer of the mask metal film

114': the second side surface layer of the mask metal film

115': Central portion of the mask metal film

116': upper layer part of the mask metal film

117': Lower portion of the mask metal film

200: Frame

210: Edge Frame Department

220: Mask Unit Sheet Department

221: Edge Sheet Section

223: First grid sheet section

225: Second Grid Sheet Section

1000: OLED pixel deposition device

C: unit, mask unit

CR: Mask Cell Region

DM: dummy part, mask dummy part

L: Laser

P: mask pattern

PS1: Surface Defect Removal Process

PS2: Thickness reduction process

WB: Weld Beads

WP: Welding Department

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

FIG. 2 is a schematic diagram of a mask according to an embodiment of the present invention.

3 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.

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

5 is a schematic diagram of a process of fabricating a mask metal film on a mask support template according to an embodiment of the present invention.

6 is a schematic diagram of a process of forming a mask by adhering a mask metal film on a template to fabricate a mask support template according to an embodiment of the present invention.

7 is a schematic diagram of a state in which a template is loaded on a frame so that a mask corresponds to a unit area of the frame according to an embodiment of the present invention.

8 is a schematic diagram of the process of separating the mask from the template after attaching the mask to the frame, according to an embodiment of the present invention.

FIG. 9 is a schematic diagram of a state of attaching a mask to a cell region of a frame according to an embodiment of the present invention.

10 is a surface photograph before and after a surface defect removal process of a mask metal film according to an experimental example of the present invention.

11 is a surface optical microscope photograph before and after a surface defect removal process is performed on a defect sample of a mask metal film according to an experimental example of the present invention.

12 is a surface AFM (Atomic Force Microscope, atomic force microscope) photograph of a defect sample of a mask metal film before and after a surface defect removal process according to an experimental example of the present invention.

FIGS. 13 to 16 show the surface defect removal of the defect sample of the mask metal film according to an experimental example. Optical microscope photos of each magnification before and after the removal process.

Detailed ways

In the following, the present invention will be described in detail with reference to the accompanying drawings, which serve to illustrate examples of specific embodiments in which the invention may be practiced. These embodiments are described in detail to enable those skilled in the art to fully practice the present invention. The various embodiments of the present invention should be understood to be mutually different but not mutually exclusive. For example, the specific shapes, structures, and characteristics described herein may enable one embodiment to be implemented into other embodiments without departing from the spirit and scope of the present invention. In addition, it should be understood that the position or arrangement of the individual constituent elements in each disclosed embodiment may be changed without departing from the spirit and scope of the present invention. Therefore, the following detailed description is not intended to limit the present invention, and the scope of the present invention is limited only by the scope of the appended claims and all equivalents thereof as long as it is properly described. Similar reference numerals in the drawings refer to the same or similar functions in various aspects, and for the sake of convenience, the length, area, thickness, etc. and their forms may also be exaggerated.

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

Hereinafter, this specification will briefly describe the structure of the frame-integrated mask, but the structure and manufacturing process of the frame-integrated mask can be understood as incorporating the entire contents of Korean Invention Patent Application No. 2018-0016186.

The conventional rod-shaped mask has a problem that, since a plurality of mask units are included in one mask, even if the tensile force applied to each axis of the rod-shaped mask is fine-tuned, the alignment between the mask units may be caused. Exactly. This is an example where the distances between the patterns of the cells are different from each other or the patterns P are uneven. The long rod-shaped mask tends to sag or twist due to the load. In order to make all the cells flat, it is very difficult to observe the alignment state of each cell through a microscope while adjusting the tensile force. The present invention can prevent the mask 100 integrated with the frame 200 from being deformed such as sagging or twisting, and can accurately align the mask 100 with the frame 200 allow.

Referring to FIG. 1 , the frame-integrated mask may include a plurality of masks 100 and a frame 200 . In other words, it is a form in which the plurality of masks 100 are attached to the frame 200, respectively. In the following, for convenience of description, the square mask 100 is used as an example, but before the mask 100 is attached to the frame 200, it may be a strip-shaped mask with protrusions for clamping on both sides and attached to the frame. The protrusions can be removed after 200.

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 unit C can correspond to one display of a smartphone or the like.

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

The frame 200 may be formed in the form of attaching a plurality of masks 100 . In consideration of thermal deformation, the frame 200 is preferably formed of Invar, super Invar, nickel, nickel-cobalt, etc., which have the same thermal expansion coefficient as the mask. The frame 200 may include a substantially quadrangular, box-shaped edge frame portion 210 . The inside of the edge frame part 210 may be hollow.

In addition, the frame 200 is provided with 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 and 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 refer to respective portions divided on the same sheet, and these are integrally formed with each other.

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 part 220 is thinner than that of the edge frame part 210 , it is thicker than the mask 100 and may be about 0.1 mm to 1 mm thick. The width of the first grid sheet portion 223 and the second grid sheet portion 225 may be about 1-5 mm.

In the flat sheet, a plurality of mask cell 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 .

The mask 200 includes a plurality of mask cell regions CR, and each mask 100 may be attached so that each mask cell C corresponds to each mask cell region CR, respectively. The mask unit C corresponds to the mask unit region CR of the frame 200, and part or all of the dummy portion may be attached to the frame 200 (mask unit sheet portion 220). Therefore, the mask 100 and the frame 200 may form an integral structure. .

FIG. 2 is a schematic diagram of a mask 100 according to an embodiment of the present invention.

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

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 is provided with a plurality of mask unit regions CR ( CR11 - CR56 ), it may also be provided with a plurality of masks 100 having a mask unit corresponding to each mask unit region CR ( CR11 - CR56 ) C(C11-C56). In addition, a plurality of templates 50 for supporting a plurality of masks 100 described later may be provided, respectively.

3 is a schematic diagram (a) of a mask metal film and a schematic diagram of surface defects of the mask metal film [(b), (c)] according to an embodiment of the present invention.

In order to manufacture the above-described mask 100 in FIG. 2 , a process of forming the mask pattern P on the mask metal film 110 needs to be performed. The mask pattern P may be formed by etching or the like. In order to achieve high-resolution OLEDs 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 or less.

Since the mask pattern P needs to be formed finely, the shape and direction of grains in the mask metal film 110 ′ should also be considered when performing etching. The etching rate differs depending on the directionality of the crystal grains, and if the uneven crystal grains are etched, it may be difficult to generate the mask pattern P of the desired width, even with a thickness of several μm . Errors can also affect high-resolution implementations.

Referring to FIG. 3( a ), in general, for a metal sheet produced by rolling, the surface, that is, the upper and lower surfaces, is compared with the central portion of the metal film, and the shape and direction of the crystal grains etc. there are differences. From the upper surface 111 ″ of the mask metal film 110 ″ to a portion 116 ″ (upper layer portion 116 ″) of a predetermined thickness and from the top surface 112 ″ to a portion 117 ″ (lower layer portion 117 ″) of a predetermined thickness with the exception of the upper layer portion 116 ″ The crystal grain characteristics are different from those of the portion corresponding to the central portion 115" other than the lower layer portion 117". The upper layer portion 116 ″ and the lower layer portion 117 ″ have irregular shapes in which the crystal grains are long aligned in the rolling direction by rolling. The crystal grains on the central portion 115" have substantially no directionality and have a spherical shape. Therefore, in order to prevent etching errors caused by different crystal grain shapes, it is preferable to consider the upper portion 116" and the lower portion 117" of the mask metal film 110". A thickness reduction process is performed, and the mask 100 is manufactured using the mask metal film 110 including the central portion 115 ″. If only the central portion 115 ″ where the crystal grains are irregular and uniform is etched and the mask pattern P is formed, the mask pattern P can be finely controlled. The advantage of the die pattern P width.

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%, at least a part of 10% to 90% of the thickness of the central portion 115 ″ can be used . To put it another way, the thickness reduction by the surface defect removal process PS1 and the thickness reduction process PS2 described later can be performed in about 10% to 90% of the overall thickness of the mask metal film 110″, and the processes PS1 and PS2 are performed on both sides. In this case, the thickness of each surface can be reduced by about 5% to 45%. However, it is not necessarily limited to this. At least a part of the thickness reduction degree in each process PS1 and PS2 can be changed.

Further, as shown in (a) of FIG. 3 , when the thickness reduction process of the mask metal film 110 ″ is performed, the defects existing on the surface can also be mainly considered.

Referring to (b) of FIG. 3 , the surface of the mask metal film 110 ′ has rolling scratches, dimples, and other scratch defects SD1 generated by pressing the metal film during rolling, and scratch defects such as SiO ₂ , Al Oxides such as ₂ O ₃ and particle defects of foreign substances SD2. These defects SD1 and SD2 still generate defects in the central portion 115 ″ after the thickness reduction process of the mask metal film 110 ′.

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

Therefore, a feature of the present invention is to manufacture the mask metal film 110 by performing a thickness reduction process after removing these surface defects SD1 and SD2. Since the thickness reduction process is performed on the planarized surface after the surface defects SD1 and SD2 are removed, the surface still has the advantage of being in a homogenized and planarized state after the thickness reduction.

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

Referring to (a) of FIG. 4 , a mask metal film 110' manufactured through a rolling process may be prepared. Surface defects SD1 and SD2 may exist on one side 111' (first side) or both sides 111' and 112' (first side and second side) of the mask metal film 110'. In the present invention, the surface defect removal and thickness reduction process can be performed only on one side 111 ′, or the surface defect removal and thickness reduction process can be performed on one side 111 ′, and then the surface defect removal and thickness reduction process can be performed on the remaining other side 112 ′ in sequence. craft. However, for the convenience of description, the case where the surface defects SD1 and SD2 are removed on both sides 111 ′ and 112 ′ at the same time and the thicknesses are reduced on both sides at the same time are illustrated below.

Next, a surface defect removal process PS1 may be performed on the surfaces 111', 112' of the mask metal film 110'. The surface defect removal process PS1 is a process for removing the scratch defect SD1 and the particle defect SD2 described in FIG. 3 .

The surface defect removal process PS1 can be performed by any one of the methods of lapping, polishing, and buffing which can be finely surface-treated. The thickness of the mask metal film 110' can also be reduced through the surface defect removal process PS1. However, it is preferable to perform it on 2.5% to 12.5% of the initial reference thickness of the mask metal film. As an example, the thickness of the mask metal film 110 ′ with a thickness of about 40 μm can be reduced by about 1˜5 μm through the surface defect removal process PS1 . This is because the surface defects SD1 and SD2 have predetermined depths, and the surface defect removal process PS1 makes at least the curvature of the depths flatter. The flatter the surface, the prevention of transfer problems based on surface morphology when performing the etching process described in Figure 3(c). In addition, the thickness reduction speed of the surface defect removal process PS1 is slower than that of the etching thickness reduction process PS2 to be described later, which is beneficial to process efficiency when processing a relatively thin thickness.

Then, referring to (b) of FIG. 4 , after the surface defect removal process PS1 , the surface layers 113 ′, 114 ′ of a predetermined thickness may be reduced and removed from the surfaces 111 ′, 112 ′. After the surface of the mask metal film 110'a is subjected to the surface defect removal process PS1, the defects are reduced and the surface becomes more flat. As described later in FIG. 11 , the depth of the scratch defect SD1 is reduced, the planar shape is changed from a laterally elongated shape to a nearly circular shape, and the particle defect SD2 may be removed.

Then, referring to (c) of FIG. 4 , a thickness reduction process PS2 may be performed. The thickness reduction of the thickness reduction process PS2 may be greater than the thickness reduction amount of the surface defect removal process PS1. In order to be able to rapidly reduce the thicker thickness, the thickness reduction process PS2 may be performed by etching, especially by wet etching. Since the surface defects SD1, SD2 of the mask metal film 110'a are removed, thickness reduction can be performed along a homogeneous surface.

The thickness reduction process PS2 may be performed for the portions 116', 117' corresponding to the predetermined thickness. The portions 116' and 117' correspond to the upper layer portion 116" and the lower layer portion 117" of the rolled Invar alloy described in (a) of FIG. 3, and are relatively irregular compared to the central portion 115'. grains. As an example, the thickness of the mask metal film 110 ′ with a thickness of about 40 μm can be reduced by about 15-34 μm.

Then, referring to (d) of FIG. 4 , portions 116 ′, 117 ′ corresponding to a predetermined thickness may be reduced and removed after the thickness reduction process PS2 is performed. After the thickness reduction, the final thickness of the mask metal film 110 may be about 5 μm to 20 μm .

In addition, the surface defect removal process PS1 and the thickness reduction process PS2 can at least only be used for The masking of the metal film 110' is performed for the portion C of the masking unit [see Fig. 2]. That is, by performing the surface defect removal process PS1 and the thickness reduction process PS2 only for the portion of the mask unit C where the mask pattern P is to be formed, the fine mask pattern P can be formed in the subsequent process. In other words, in order to make the mask 100 described later well adhere to the frame 200 by welding [see FIG. 7 ], the welding portion WP may be formed at least thicker than the mask unit C. FIG. For this reason, the surface defect removal process PS1 and the thickness reduction process PS2 may be performed only on the portion other than the welded portion WP (or at least a part of the dummy portion DM).

After the surface defect removal process PS1, insulating parts such as photoresist (not shown) are formed on other parts of the mask unit C than the mask unit C, and the thickness reduction process PS2 is performed on the mask unit C part, so as to be connected with the mask unit C part. , Welding part WP [or dummy part DM] can produce thickness difference and form step difference. Thus, the thickness of the other parts except the mask unit C part or the welding part WP part may be about 5 μm to 20 μm , and the welding part WP or the dummy part DM part may have a thicker thickness.

Since the mask metal film 110 of the present invention includes the central portion 115 ′ of the rolled metal film, the grain shape is regular, and since the mask metal film 110 has a homogeneous surface and no defects on the surface, in the process for forming the mask pattern P, it has The effect of precision etching process can be carried out.

5 is a schematic diagram of a process of fabricating a mask metal film on a mask support template according to an embodiment of the present invention.

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 the template 50 described later in FIG. 6 , and can be replaced by the template 50 . It is possible to form the mask pattern P immediately after forming the mask metal film 110 on the template 50 to manufacture the mask 100, and to move the template 50 supporting the mask 100 to the frame 200 and immediately manufacture the frame-integrated mask. advantage.

5(a), the lower surface 112' of the mask metal film 110' (the second surface, that is, the opposite surface of the first surface 111') can be bonded to the support substrate 40 by using the bonding portion 41. The adhesive portion 41 can be made of the same material as the temporary adhesive portion 55 described later, or a material that has a certain adhesive force and can be separated afterward. can be used without restriction.

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 portion 116' may be reduced and removed.

The state of the support substrate 40, the bonding portion 41, and the mask metal film 110'b can be directly replaced by step (b) of FIG. 6 to be described later. At this time, the support substrate 45 may correspond to the template 50 , and the adhesive portion 45 may correspond to a temporary adhesive portion 55 to be described later. Even if surface defects are removed on one side but not both sides of the mask metal film 110' and a thickness reduction process is performed, the defect 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 direction of the first surface from which surface defects are removed. The case where the process is performed on both sides will be further explained by (b) to (d) of FIG. 5 .

Then, referring to FIG. 5( b ), another supporting substrate 45 is prepared, and then the upper surface (first surface) of the mask metal film 110 ′b can be adhered to the supporting substrate 45 by using the adhesive portion 46 . The support substrate 45 and the adhesive portion 45 may be the same as the support substrate 40 and the adhesive portion 41 . In addition, the support substrate 45 may correspond to the template 50 described later, and the adhesive portion 45 may correspond to the temporary adhesive portion 55 described later. In this case, the steps (b) to (d) of FIG. 5 can also be replaced by the step (b) of FIG. 6 .

Then, referring to (c) of FIG. 5 , after the mask metal film 110 ′b is bonded to the support substrate 45 , the support substrate 40 may be separated. Next, a surface defect removal process PS1 and a thickness reduction process PS2 may be performed on the second surface 112". After the surface defect removal process PS1, the surface layer 114' of the mask metal film 110" may be After PS2, the lower layer portion 117' may be reduced and removed.

Then, referring to (d) of FIG. 5 , the fabrication of the mask metal film 110 can 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 .

In addition, in FIGS. 4 and 5 , it is assumed that the mask metal film 110 is made by a rolling process, and even in the case of a mask metal film made by other processes such as electroforming, the surface portion and the center Part of the die may also have feature differences, so the same process PS1 and PS2 can be used.

6 is a schematic diagram of a process of forming a mask 100 by adhering a mask metal film 110 on a template 50 to fabricate a mask support template according to an embodiment of the present invention.

(a) of FIG. 6, a template 50 (template) can be provided. The template 50 is a medium to which the mask 100 is attached and moves the mask 100 in a state of supporting the mask 100 . The center portion 50 a may correspond to the mask unit C of the mask metal film 110 , and the edge portion 50 b may correspond to the dummy portion DM of the mask metal film 110 . In order to be able to support the mask metal film 110 as a whole, the template 50 has a flat shape with an area larger than or equal to the mask metal film 110 .

The template 50 preferably uses a transparent material in order to facilitate vision observation during the process of aligning and adhering the mask 100 to the frame 200 . In addition, in the case of a transparent material, the laser can be penetrated. As the transparent material, glass, silica, heat-resistant glass, quartz, alumina (Al2O3), borosilicate glass, zirconia and the like can be used. As an example, the template 50 may use BOROFLOAT® 33 material in borosilicate glass having excellent heat resistance, chemical durability, mechanical strength, transparency, and the like. In addition, the thermal expansion coefficient of BOROFLOAT® 33 is about 3.3, and the difference between the thermal expansion coefficient of the invar mask metal film 110 and the thermal expansion coefficient of the Invar mask metal film 110 is small, which has the advantage of easy control of the mask metal film 110 .

In addition, in order not to generate an air gap between the interface with the mask metal film 110 (or the mask 100 ), the surface of the template 50 in contact with the mask metal film 110 may be a mirror surface. Taking this into consideration, the surface roughness (Ra) of one side of the template 50 may be 100 nm or less. In order to realize the template 50 having a surface roughness (Ra) of 100 nm or less, a wafer may be used for the template 50 . The surface roughness (Ra) of a 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 the template 50 . The surface roughness (Ra) of the stencil 50 is nano-scale so that there is no or almost no air gap, and solder beads (WB) are easily generated by laser welding, so the alignment error of the mask pattern P may not be affected.

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

The positions and the number of the laser passing holes 51 do not necessarily correspond to the positions and the number of the welding portions WP. For example, only part of the laser passing holes 51 may be irradiated with the laser beam L to perform welding. In addition, the part of the laser passing hole 51 that does not correspond to the welding part WP can 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 light L, the laser passing hole 51 may not be formed.

One side of the template 50 may form a temporary bonding portion 55 . Before the mask 100 is attached to the frame 200 , the temporary adhesive portion 55 may temporarily attach the mask 100 (or the mask metal film 110 ′) to one side of the template 50 and support it on the template 50 .

The temporary adhesive part 55 may use a heat-based detachable adhesive or an adhesive sheet, a UV-irradiated-based detachable adhesive or an adhesive sheet.

As an example, liquid wax may be used for the temporary adhesive portion 55 . As the liquid wax, the same wax used in the polishing step of the semiconductor wafer and the like can be used, and the type thereof is not particularly limited. As a resin component mainly used for controlling adhesion, impact resistance, etc. related to holding force, the liquid wax may include substances and solvents such as acrylic acid, vinyl acetate, nylon, and various polymers. As an example, the temporary adhesive portion 55 may use SKYLIQUIDABR-4016 including Acrylonitrile butadiene rubber (ABR) as a resin component and n-propanol as a solvent component. Liquid wax is formed on the temporary adhesive portion 55 using a spin coating method.

The temporary adhesive part 55, which is a liquid wax, decreases in viscosity at a temperature higher than 85° C. to 100° C., and increases in viscosity at a temperature lower than 85° C., and a part is cured into a solid, so that the mask metal film can be cured. 110' is fixedly bonded to the template 50.

Next, referring to (b) of FIG. 6 , the mask metal film 110 may be bonded on the template 50 . The liquid wax may be heated to above 85° C., and the mask metal film 110 is brought into contact with the template 50 , and then the mask metal film 110 and the template 50 are passed between rollers for bonding.

According to one embodiment, the template 50 is baked at about 120° C. for 60 seconds to vaporize the solvent of the temporary bonding portion 55 , and then the mask metal film lamination process can be performed immediately. Lamination is performed by loading the mask metal film 110 on the template 50 with the temporary adhesive portion 55 formed on one side and passing it between an upper roll at about 100°C and a lower roll at about 0°C. As a result, the mask metal film 110' can be brought into contact with the template 50 by interposing the temporary adhesive portion 55 therebetween.

As yet another example, thermal release tape may be used for the temporary adhesive portion 55 . The thermal release tape is a base film with a PET film or the like arranged in the middle, a thermal release adhesive is arranged on both sides of the base film, and a release film/release film can be arranged on the outer contour of the adhesive layer. Here, the separation temperatures of the adhesive layers arranged on both sides of the base film may be different from each other.

According to an embodiment, in the state where the separation film/release film is removed, the lower surface of the thermal release tape [the lower second adhesive layer of the base film] is adhered to the template 50, and the upper surface of the thermal release tape [the upper part of the base film] The first adhesive layer] may be adhered on the mask metal film 110'. The separation temperatures of the first adhesive layer and the second adhesive layer are different from each other. Therefore, in FIG. 16 to be described later, when the template 50 is separated from the mask 100, the mask 100 can be separated from the template as the first adhesive layer is heated. 50 and the temporary adhesive portion 55 are separated.

In addition, the mask metal film 110 in which the processes PS1, PS2 of FIG. 4 are performed on one side or both sides may be used. Alternatively, (b) of FIG. 6 may be replaced with a state after the processes PS1 and PS2 are performed on one side after the mask metal film 110' is adhered to the support substrate 40 (corresponding to the template 50) in step (a) of FIG. 5 . In addition, (b) of FIG. 6 may be replaced by processes PS1 and PS2 on one side after bonding the mask metal film 110 ′ to the support substrate 40 (corresponding to the template) as shown in (a) to (d) of FIG. 5 , The state after the processes PS1 and P2 are performed on the other side after the mask metal film 110'b is bonded to the support substrate 45 (corresponding to the second).

In addition, the thickness reduction process PS2 of FIG. 4 and FIG. 5 can only be performed for the part C of the mask unit. After the surface defect removal process PS1, an insulating portion (not shown) such as photoresist is formed only in the region corresponding to the welding portion WP of the mask metal film 110 ′, or the mask metal film 110 ′ is adhered and supported on the template 50 In the above state, only an insulating portion (not shown) such as photoresist is formed in the region corresponding to the welding portion WP of the mask metal film 110', and then the process PS2 is performed on the part C of the mask unit, so that the welding portion WP is relatively smaller. A thick thickness is formed and a step is formed 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 in a defect-free state.

In addition, an insulating portion (not shown) such as photoresist may be further formed on the lower surface of the mask metal film 110 , and the insulating portion may be sandwiched between the mask metal film 110 and the temporary bonding portion 55 for bonding. . In step (c) of FIG. 6 , in order to prevent the etchant from penetrating into the interface between the mask metal film 110 and the temporary bonding portion 55 to damage the temporary bonding portion 55/template 50 and generate an etching error of the mask pattern P, further forming Insulation part. In order to have strong durability to the etching solution, the insulating portion may include at least one of a curable negative-type photoresist, an epoxy-containing negative-type photoresist. As an example, preferably, by using epoxy-based SU-8 photoresist, the baking of the black matrix photoresist on the temporary bonding portion 55, the baking of the insulating portion 25 (refer to (c of FIG. 6) )) and other processes to cure together.

Then, referring to (c) of FIG. 6 , the patterned insulating portion 25 may be formed on the mask metal film 110 . The insulating portion 25 can be formed of a photoresist material by a printing method or the like.

Next, the mask metal film 110 may be etched. Dry etching, wet etching, etc. may be used without limitation, and as a result of the etching, portions of the mask metal film 110 exposed by the blank spaces 26 between the insulating portions 25 may be etched away. The etched portion of the mask metal film 110 forms the mask pattern P, so that the mask 100 in which the plurality of mask patterns P are formed can be manufactured.

At this time, since the mask metal film 110 is in a state in which surface defects have been removed, etching can be performed in a desired pattern form in the etching process. The fine mask pattern P can be formed, and thus has the effect of being able to manufacture the mask 100 that can be used in a high-resolution OLED pixel process.

Then, referring to (d) of FIG. 6 , the manufacture of the template 50 supporting the mask 100 can be completed by removing the insulating portion 25 .

In addition, instead of the steps (b) and (c) of FIG. 6 , 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 temporary bonding interposed therebetween. portion 55 so that the template 50 for supporting the mask 100d can be fabricated.

7 is a schematic diagram of a state in which the template 50 is loaded on the frame 200 and the mask 100 is mapped to the unit region CR of the frame 200 according to an embodiment of the present invention. FIG. 7 enumerates the method of corresponding/attaching one mask 100 to the unit region CR, and a process of simultaneously corresponding multiple masks 100 to all the unit regions CR and attaching the masks 100 to the frame 200 is also possible. At this time, there may be a plurality of templates 50 supporting the plurality of masks 100, respectively.

Template 50 can be transferred by vacuum chuck 90 . The surface opposite to the surface to which the template 50 of the mask 100 is adhered can be sucked and transferred by the vacuum chuck 90 . After the vacuum chuck 90 sucks the template 50 and turns it over, the process of transferring the template 50 to the frame 200 will not affect the bonding state and alignment state of the mask 100 .

Next, referring to FIG. 7 , the mask 100 may be corresponding to one mask unit region CR of the frame 200 . The mask 100 can be made to correspond to the mask unit region CR by loading the template 50 to the frame 200 [or the mask unit sheet portion 220]. Whether the mask 100 corresponds to the mask cell region CR can be observed through a microscope while controlling the position of the template 50/vacuum chuck 90 . Since the template 50 presses the mask 100 , the mask 100 can be tightly attached to the frame 200 .

In addition, the lower part of the frame 200 may be further arranged with a lower support body 70 . The lower supporter 70 may press the reverse side of the mask cell 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 without be disrupted.

Next, the mask 100 is irradiated with the laser L and attached to the frame 200 based on laser welding. Solder beads WB are generated on the welding portion WP of the mask welded by the laser, and the solder beads WB may have Same material as mask 100/frame 200 and integrally connected with them.

8 is a schematic diagram of the process of separating the mask from the template after attaching the mask to the frame, according to an embodiment of the present invention.

Referring to FIG. 8 , after the mask 100 is attached to the frame 200 , the mask 100 and the template 50 may be debonded. The separation of the mask 100 from the template 50 may be performed by at least any one of heating ET, chemical treatment CM, application of ultrasonic waves US, and application of ultraviolet rays UV to the temporary adhesive portion 55 . Since the mask 100 remains attached to the frame 200, only the template 50 can be lifted. As an example, if thermal ET at a temperature higher than 85° C. to 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 mask 100 may be separated from the template 50 by immersing the temporary bond 55 in a chemical such as IPA, acetone, ethanol, etc. to dissolve, remove, etc. the temporary bond 55 . As another example, the adhesive force between the mask 100 and the template 50 is weakened by applying ultrasonic waves US or ultraviolet UV, so that the mask 100 and the template 50 can be separated.

FIG. 9 is a schematic diagram of a state in which the mask 100 is attached to the frame 200 according to an embodiment of the present invention. A state in which all the masks 100 are attached to the cell region CR of the frame 200 is illustrated in FIG. 14 . 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.

The template 50 is separated from the mask 100 by the vacuum chuck 90 , and the first insulating portion 23 remains on the mask 100 . If the first insulating portion 23 is a curable photoresist, it is difficult to be removed 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 may be applied. A process of removing only the first insulating portion 23 by applying atmospheric pressure plasma or vacuum plasma PS or ultraviolet UV after loading the frame-integrated masks 100 and 200 in another chamber (not shown) may be performed.

FIG. 9 is a state of attaching the mask 100 to the frame 200 according to an embodiment of the present invention Schematic.

Referring to FIG. 9 , one mask 100 may be adhered 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 adhered 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 The mask unit sheet portion 220 and the mask unit region CR are deformed. Therefore, the mask 100 should be adhered to the mask unit sheet portion 220 in a state where no tensile force is applied to the mask 100 . In the present invention, only by attaching the mask 100 on the template 50 and loading the template 50 on the frame 200, the process of the mask 100 corresponding to the mask unit region CR of the frame 200 can be completed, and this process does not apply any tension to the mask 100. stretch.

Since it is only necessary to correspond to one cell C of the mask 100 and confirm the alignment state, the present invention can significantly shorten the time compared with the existing method that simultaneously corresponds to a plurality of cells C (C1-C6) and needs to confirm all the alignment states manufacturing time.

In addition, in (b) of FIG. 6 , as described above, when the mask metal film 110 is adhered to the template 50 through the lamination process, a temperature of about 100° C. is applied to the mask metal film 110 . Based on this, the mask metal film 110 is adhered to the template 50 in a state where a partial tensile force is applied. 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 be shrunk by a certain amount.

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 plurality of masks 100 exert tensions that shrink in opposite directions, the tensions cancel each other out, Therefore, deformation of the mask unit sheet portion 220 does not occur. For example, on the first grid sheet portion 223 between the mask 100 attached to the CR11 cell region and the mask 100 attached to the CR12 cell region, the mask 100 attached to the CR11 cell region acts in the right direction. The tension and the tension acting in the left direction of the mask 100 attached to the CR12 unit area can cancel each other out. Accordingly, deformation of the frame 200 (or the mask unit sheet portion 220 ) due to tension is minimized, thereby having an advantage of minimizing the alignment error of the mask 100 (or, the mask pattern P).

Next, through an experimental example to understand the surface defect removal process PS1 detailed in FIG. 4 to remove surface defects SD1 and SD2.

10 is a surface photograph before and after a surface defect removal process of a mask metal film according to an experimental example of the present invention. (a) and (c) and (b) and (d) of FIG. 10 are used to show before and after the process in the same region.

According to an experimental example, the surface defect removal process PS1 was performed on a rolled Invar metal film with a thickness of 40 μm by buffing with a thickness of 2 μm .

As can be seen from (a) and (b) of FIG. 10 , the surface of the mask metal film has scratch defects SD1 such as rolling scratches generated when the metal film is pressed during the rolling process. Considering that the rolling direction is the x-axis direction, it can be confirmed that (a) is an elongated scratch defect SD1 of 100 μm or more, (b) is a 10 μm or more elongated scratch defect SD1 and scratch defect SD1. Particle defects SD2 of oxides such as SiO ₂ and Al ₂ O ₃ and foreign substances are formed therein.

Referring to (c) of FIG. 10 , it can be confirmed that the scratch defect SD1 has been removed. Although it is an elongated scratch defect SD1 of 100 μm or more, since the depth of the defect is less than 2 μm , the defect can be removed.

In addition, referring to FIG. 10( d ), it was confirmed that the shape of the elongated scratch defect SD1 was changed to a quasi-circular shape, and the particle defect SD2 was removed. That is, the size of the scratch defect SD1 is 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 was confirmed that the shape of the elongated scratch defect SD1 became 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, uniform flatness can be maintained due to the small curvature shape of the defect. Ultimately, even if the defect morphology is transferred during the etching process, there will be no error or negligible.

The table below shows the number and size of defects before and after the surface defect removal process PS1. Defects existing in an area of 100 mm×100 mm were confirmed for 9 samples.

Referring to Table 1, it can be seen that defect removal/reduction occurred in all 9 samples after the process. Defects in samples 1, 8, and 9 were all removed. Samples 2 to 7 showed that the number of defects remained unchanged or decreased, and these defects coexisted with scratch defect SD1 and particle defect SD2, and it was confirmed that the shape of scratch defect SD1 changed from an elongated shape to a circular shape.

Referring to Table 2, it can be seen that the size of the defect is reduced. In other words, in the samples 2 to 7, it was confirmed that the size of the elongated scratch defect SD1 became small and the shape became circular.

The elongated scratch defect SD1 is a defect whose lateral length is larger than the vertical length on a plane. That is, (x-axis length): (y-axis length) is k:l (k, l is a positive number), and k may be greater than l. The defect becomes circular after the process PS1, (x-axis length): (y-axis length) is m:n (m, n is a positive number), and k/l>m/n. That is, at least the lateral length is reduced, the vertical length is increased, and the defects are reduced.

As a result, the mask metal film 110 of the present invention can have round or quasi-round defects on the surface. Alternatively, the elongated scratch defect SD1 also remains as a substantially elliptical defect as the frame becomes rounded.

Defect SD1 can change into a flatter morphology as the curvature decreases. As the defect SD1 becomes a circular shape, the curvature of the edge of the defect SD1 becomes smaller, the depth of the defect becomes smaller, and the defect SD1 becomes flat. At this time, the flattened defect is observed, and the angle formed by the side surface 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 the depth direction is aligned with the surface of the mask metal film 110 without bending. When the processes PS1 and PS2 of the mask metal film 110 are completed and the mask pattern P is formed, the side surface of the mask pattern P can be formed with an angle of about 45° to the xy plane (or the surface of the mask metal film 110 ). Inverted taper with 70° taper angle. 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 is similar to the mask pattern. Since the form of P remains, the side angle of the defect should be sufficiently smaller than the angle of the mask pattern P.

11 is a surface optical microscope photograph before and after a surface defect removal process for a defect sample of a mask metal film according to an experimental example of the present invention. Figure 11 is a photograph of four identifiable defects (#1 to #4) extracted in one sample.

Referring to FIG. 11( a ), it can be seen that #1 to #4 are all 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 also included in the scratch defect SD1.

Referring to FIG. 11( b ), it can be seen that after the process PS1 , most of the defects in #1 to #4 except for the defects indicated by the dotted circles have been removed. In #1, #3, and #4, it was confirmed that the elongated scratch defect SD1 including the particle defect SD2 was circular. In addition, after the process PS1, the depth of the color was reduced, and it was confirmed that the depth of the defect was also reduced.

12 is an AFM (Atomic Force Microscope) photograph of the surface before and after a surface defect removal process for a defect sample of a mask metal film according to an experimental example of the present invention.

Referring to FIG. 12, it can be easily found that the surface of the mask metal film becomes more homogeneous after the process PS1. Figure 12(a) shows the light and dark of the horizontal stripes, and each part of the surface shows a large height difference. On the contrary, in Figure 12(b), except for the dotted circle part, the light and dark show a gradual change, and the height of the surface part shows a relative flat Tan. In addition, after the process PS1, the color depth of the portion circled by the dotted line was reduced, and it was confirmed that the depth of the defect was also reduced.

FIGS. 13 to 16 are optical microscope photographs of each magnification before and after a surface defect removal process for a defect sample of a mask metal film according to an experimental example. FIG. 13 , FIG. 14 , FIG. 15 , and FIG. 16 are photographs of #1, #2, #3, and #4 defects observed at magnifications of 50 times, 200 times, 500 times, and 1000 times, respectively. The zigzag thick lines around the dashed circle are arbitrarily marked on the surface for the convenience of defect observation.

13, 15 and 16, it can be confirmed that the defects #1, #3 and #4 are all elongated defects. In particular, it was confirmed that the defect indicated by the dotted circle was a defect in which the particle defect SD2 was also included in the scratch defect SD1. In addition, it was confirmed that the elongated scratch defect SD1 including the particle defect SD2 became circular. After the process PS1, the color depth was reduced, and it was confirmed that the depth of the defect was also reduced.

Referring to FIG. 14 , it can be seen that defect #2 is also an elongated defect. In particular, it was confirmed that the defect indicated by the dotted circle is a defect in which the particle defect SD2 is also included in the scratch defect SD1. However, Defect #2 is shown to the extent that it was removed after process PS1. This can be understood as the case that the depth of the particle defect SD2 in the process PS1 is shallow or that the particle defect SD2 is detached and appears non-circular at the initial stage, and the defect is removed.

The following table shows the defect size after the surface defect removal process PS1 determined by FIGS. 13 to 16 .

Referring to Table 3, it can be seen that in all the four defects, the particle defect SD2 is removed after the process PS1. In addition, it can be confirmed that the length of the x-axis decreases at the rate of increase and decrease of -45.5%, -25.2%, -4.8%, and -14.8%, and the length of the y-axis decreases at the rate of increase and decrease of 45.1%, 13.2%, 36.2%, and 15.0%. Increase. From this, it can be seen that the form of the defect From slender to round.

In addition, the ratio of (x-axis length): (y-axis length) of the four defects after the process PS1 is approximately equivalent to 1.41:1, 1.30:1, 2.49:1, and 2.47:1. Defects SD1, SD20 that exceed 3:1 before the process PS1 become circular after the process PS1, or become nearly elliptical with a ratio of (x-axis length):(y-axis length) from 1:1 to 3:1 . It can be confirmed that the x-axis length or the y-axis length of the defect is less than 30 μm .

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

As described above, the present invention is illustrated and described with reference to the preferred embodiments, but the present invention is not limited to the above-described embodiments, and various modifications and changes can be made by those skilled in the art without departing from the spirit of the present invention. Such deformations and changes belong to the scope of the present invention and the appended claims.

Claims (24)

A mask metal film support template for supporting and corresponding to a frame of a mask metal film used in manufacturing a mask for forming an OLED pixel, wherein the template includes: a template; and a temporary adhesive portion formed on the on the template; and a mask metal film bonded to the template by sandwiching the temporary bonding portion, the mask metal film having scratch defects generated by a rolling process on at least one side At least one side of the metal film (sheet) is manufactured by sequentially performing a surface defect removal process and a thickness reduction process, and the surface defect removal process is performed by any one of lapping, polishing, and buffing. , after the surface defect removal process and the thickness reduction process, the size of the scratch defect is reduced to the ratio of the x-axis length:y-axis length of 1:1 or more and less than 3:1 [x-axis direction and The rolling direction is parallel]. The mask metal film support template according to claim 1, wherein the scratch defect does not exist in a state of particles. 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°. The mask metal film support template of claim 1, wherein the width of the scratch defect is less than 30 μm (over 0). The mask metal film supporting template of claim 1, wherein the mask metal film has a thickness of 5 μm to 20 μm . 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 reference thickness of the metal film, so that the x-axis length of the scratch defect: y The ratio of the axis length is changed from k: l [k, l are positive numbers, k is a number greater than l] to m: n [m, n are positive numbers, and satisfy k/l>m/n]. The mask metal film support template of claim 5, wherein the thickness reduction process is performed by wet etching. The mask metal film supporting template according to claim 1, wherein the mask metal film includes a mask cell region as a region for forming a mask pattern and a dummy part region around the mask cell region, the The thickness of the portion corresponding to the welded portion in the dummy portion region is at least greater than the thickness of the remaining region. 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 The metal film uses at least a part corresponding to 10% to 90% of the thickness of the metal film. A manufacturing method of a mask metal film support template for supporting a mask metal film for OLED pixel formation and corresponding to a frame, wherein the method comprises the following steps: (a) The metal film produced by the rolling process is bonded to a template with a temporary bonding portion formed on one side; (b) the surface defects are removed and the thickness is reduced on the first side of the metal film; (c) the first side of the metal film is The thickness is reduced by etching on the surface to prepare the template for bonding and supporting the mask metal film. In the step (a), at least one side of the metal film has scratch defects generated by the rolling process. In the step (b), the surface defect removal process is performed by any one of grinding, polishing, and polishing, and after the step (b) and the step (c), the scratch defects are removed. The size is reduced to a ratio of x-axis length:y-axis length of 1:1 or more and less than 3:1 [the x-axis direction is parallel to the rolling direction]. The method for manufacturing a mask metal film supporting template according to claim 10, wherein step (a) comprises the following steps: (a1) forming an insulating portion on the second side, which is the opposite side of the first side of the metal film; (a2) The metal film is bonded to the upper surface of the template by interposing the insulating portion on the template on which the temporary bonding portion is formed on one surface. The method for manufacturing a mask metal film supporting template according to claim 10, further comprising the following steps: (d) separating the mask metal film from the template; (e) separating the mask metal film Adhering the first side of the film to a second template with temporary adhesives formed on one side; (f) removing surface defects and reducing the thickness on the second side opposite to the first side of the mask metal film; (g) The thickness of the second surface of the mask metal film is reduced by etching. The method for manufacturing a mask metal film supporting template according to claim 10, wherein the thickness reduction of the step (b) is performed for 2.5% to 12.5% of the initial reference thickness of the metal film. The method for manufacturing a mask metal film support template as claimed in claim 13, wherein the thickness reduction of the step (c) is performed by an amount greater than the thickness reduction of the step (b). The method for manufacturing a mask metal film supporting template according to claim 14, wherein the step (c) is performed by wet etching. The method for manufacturing a mask metal film supporting template according to claim 14, wherein after the step (c), the thickness of the mask metal film is 5 μm to 20 μm . The method for manufacturing a mask metal film support template according to claim 10, wherein, after the step (b), the defect morphology existing on the first surface of the metal film is the length of the x-axis: the length of the y-axis The ratio is changed from k: l [k, l are positive numbers, k is a number greater than l] to m: n [m, n are positive numbers], and k/l>m/n is satisfied. The method of manufacturing a mask metal film supporting template according to claim 10, wherein after the step (b), particles included in the defects on the first surface of the metal film are removed. The method of manufacturing a mask metal film supporting template according to claim 10, wherein after the step (b), in the remaining area except the mask unit portion of the metal film or in the An insulating portion is formed on the welding portion region of the metal film, and step (c) is performed on the region where the insulating portion is not formed. The method of manufacturing a mask metal film supporting template as claimed in claim 10, wherein the method further comprises the step of: (d) manufacturing a mask by forming a mask pattern on the mask metal film. A method for manufacturing a mask support template for supporting a mask for forming an OLED pixel and corresponding to a frame, the method comprising the steps of: (a) preparing a metal film manufactured by a rolling process; (b) removing surface defects and reducing the thickness on the first side of the metal film; (c) reducing the thickness by etching on the first side of the metal film to prepare a mask metal film; (d) reducing the thickness by etching on the first side of the metal film; forming a mask pattern on the mask metal film to manufacture a mask; and (e) adhering the mask to a template with a temporary adhesive portion formed on one side, in the step (a), the metal film At least one side has scratch defects produced by the rolling process. In the step (b), the surface defect removal process is performed by any one of grinding, polishing, and polishing. In the step (b) And after the step (c), the size of the scratch defect is reduced to a ratio of x-axis length:y-axis length of 1:1 or more and less than 3:1 [x-axis direction is parallel to the rolling direction]. A mask metal film for manufacturing a mask for OLED pixel formation, wherein the mask metal film is subjected to surface defect removal by sequentially performing surface defect removal on at least one side of a metal film having scratch defects generated by a rolling process on at least one side process and thickness reduction process, the surface defect removal process is performed by any one of grinding, polishing, and polishing, and after the surface defect removal process and the thickness reduction process, the size of the scratch defect The ratio of the x-axis length:y-axis length is reduced to 1:1 or more and less than 3:1 [the x-axis direction is parallel to the rolling direction]. A manufacturing method of a mask metal film, comprising the following steps: (a) preparing a metal film produced by a rolling process; (b) removing surface defects and reducing thickness on the first side of the metal film; and (c) reducing by etching on the first side of the metal film thickness to prepare a mask metal film, in the step (a), at least one side of the metal film has scratch defects generated by a rolling process, in the step (b), the surface defects are removed The process is performed by any one of grinding, polishing, and polishing, and after the step (b) and the step (c), the size of the scratch defect is reduced to a ratio of x-axis length:y-axis length It is 1:1 or more and less than 3:1 [x-axis direction and rolling direction are parallel]. A method of manufacturing a frame-integrated mask, the frame-integrated mask is integrally formed by at least one mask and a frame for supporting the mask, wherein the method comprises the steps of: (a) applying the method of claim 21 A mask support template manufactured by the method described is loaded 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 onto the frame.

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