Deposition mask, manufacturing method thereof, and deposition mask assembly including deposition mask

Abstract

Provided are a deposition mask manufactured by complexly applying an etching method and a plating method, a manufacturing method thereof, and a deposition mask assembly including the deposition mask. The method for manufacturing a deposition mask includes the steps of: forming a resist on a first surface and a second surface of a metal plate; leaving a plurality of first resist patterns on the second surface; forming a plating layer on the remaining part except for the part in which the first resist patterns remain; leaving a plurality of second resist patterns on the first surface; etching the remaining part except for the part in which the second resist patterns remain; and peeling off the first resist patterns and the second resist patterns.

Description

Deposition mask and method for manufacturing the same, and deposition mask assembly including the deposition mask

[0001] The present invention relates to a deposition mask used in OLED organic material deposition, a method for manufacturing the same, and a deposition mask assembly including the deposition mask.

[0002] When manufacturing a deposition mask, photoresist is applied to both sides of a metal plate manufactured through a rolling process, and holes penetrating the metal plate can be formed by etching. A deposition mask manufactured in this manner may include a number of penetration holes and a number of inclusions unevenly distributed on the surface or interior of the metal plate.

[0003] When metal plates are manufactured by rolling, defects such as scratches and dents can occur in the metal plate. Furthermore, these defects can also be caused by inclusions within the metal plate. When forming through holes in a metal plate, if these defects exist in the boundary area of ​​the etching process, they can cause overetching defects during the hole etching process, resulting in an uneven size of the through hole.

[0004] The technical problem to be solved by the present invention is to provide a deposition mask manufactured by applying a composite etching method and a plating method, a manufacturing method thereof, and a deposition mask assembly including the deposition mask.

[0005] The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0006] An aspect of a deposition mask manufacturing method of the present invention for achieving the above technical task comprises: forming a resist on a first surface and a second surface of a metal plate; leaving a plurality of first resist patterns on the second surface; forming a plating layer on a portion remaining except for a portion where the first resist patterns remain; leaving a plurality of second resist patterns on the first surface; etching a portion remaining except for a portion where the second resist patterns remain; and peeling off the first resist pattern and the second resist pattern.

[0007] One side of the deposition mask of the present invention for achieving the above technical task is manufactured by the above deposition mask manufacturing method.

[0008] Another aspect of the deposition mask of the present invention for achieving the above technical task comprises: a metal plate defining a first surface and a second surface; at least one first groove penetrating the first surface and the second surface; and a plating layer including a second groove corresponding to the first groove on the second surface, wherein the second surface includes groove-shaped defects, and some of the defects are filled with the plating layer.

[0009] One aspect of the deposition mask assembly of the present invention for achieving the above technical task includes: a frame; a deposition mask disposed on the frame and manufactured according to the deposition mask manufacturing method; and a support for fixing the deposition mask to the frame.

[0010] Specific details of other embodiments are included in the detailed description and drawings.

[0011] According to the present invention, the following effects can be obtained by combining the advantages of a rolled substrate and a plated substrate and manufacturing a deposition mask by applying a mixed etching process and a plating process.

[0012] First, by using a rolled base material as a core, the coefficient of thermal expansion (CTE) and rigidity can be maintained, and by performing plating with the same composition on the pore surface, defects caused by inclusions and surface defects, which are problems of the rolled base material, can be suppressed.

[0013] Second, the etching method can achieve a low and uniform step height (SH), high hole size uniformity, and small corner-R (CR) value.

[0014] Third, it is suitable for manufacturing high-resolution organic light-emitting displays of 500ppi or more.

[0015] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

[0016] Figure 1 is an exemplary diagram illustrating the structure of a deposition mask.

[0017] Figure 2 is an exemplary diagram illustrating components formed in an effective area within a metal plate.

[0018] Figure 3 is an exemplary diagram illustrating a defect formed on the surface of a metal plate.

[0019] Figure 4 is a first example diagram for explaining a problem caused by a defect formed on the surface of a metal plate.

[0020] Figure 5 is a second example diagram for explaining a problem caused by a defect formed on the surface of a metal plate.

[0021] Figure 6 is an exemplary diagram illustrating a method for solving a defect problem formed on the surface of a metal plate.

[0022] Figure 7 is a flowchart sequentially explaining a method for manufacturing a deposition mask.

[0023] Figure 8 is an exemplary diagram for explaining a resist application process among deposition mask manufacturing methods.

[0024] Figure 9 is an exemplary diagram for explaining the exposure process and the first development process among the deposition mask manufacturing methods.

[0025] Figure 10 is an exemplary diagram for explaining a plating process among deposition mask manufacturing methods.

[0026] Figure 11 is an exemplary diagram illustrating a protective layer formation process among deposition mask manufacturing methods.

[0027] Figure 12 is a first exemplary diagram for explaining the second development process among the deposition mask manufacturing methods.

[0028] Figure 13a is a second exemplary diagram for explaining the second development process in the deposition mask manufacturing method.

[0029] Figure 13b is a third exemplary diagram for explaining the second development process among the deposition mask manufacturing methods.

[0030] Figure 13c is a fourth exemplary diagram for explaining the second development process among the deposition mask manufacturing methods.

[0031] Figure 14 is a first example diagram for explaining an etching process among deposition mask manufacturing methods.

[0032] Figure 15 is a second example diagram for explaining an etching process among deposition mask manufacturing methods.

[0033] Figure 16 is a third example diagram for explaining an etching process among deposition mask manufacturing methods.

[0034] Figure 17 is a fourth example diagram for explaining an etching process among deposition mask manufacturing methods.

[0035] Figure 18 is an exemplary diagram illustrating a peeling process among deposition mask manufacturing methods.

[0036] FIG. 19 is a first exemplary drawing illustrating a deposition mask assembly including a deposition mask.

[0037] FIG. 20 is a second exemplary drawing illustrating a deposition mask assembly including a deposition mask.

[0038] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. Identical components in the drawings are designated by the same reference numerals, and redundant descriptions thereof will be omitted.

[0039] Fig. 1 is an exemplary diagram for explaining the structure of a deposition mask. In Fig. 1, a first direction (D1) and a second direction (D2) form a plane in a horizontal direction. For example, the first direction (D1) may be a front-back direction, and the second direction (D2) may be a left-right direction. Alternatively, the first direction (D1) may be a left-right direction, and the second direction (D2) may be a front-back direction. A third direction (D3) is a height direction, and is a direction perpendicular to a plane formed by the first direction (D1) and the second direction (D2). The third direction (D3) may be an up-down direction.

[0040] The deposition mask (100) is also called a metal mask, and has a structure in which a through hole penetrating the metal plate (110) is formed for each of an effective area (120) and an ineffective area (130). The deposition mask (100) can deposit an organic material on a display panel (e.g., an OLED panel) applied to an organic light-emitting display, for example, an OLED (Organic Light Emitting Diodes) using the through hole. The deposition mask (100) can deposit various types of organic materials, such as red (R), green (G), and blue (B), on the panel using the through hole in a vacuum atmosphere, and accordingly, an RGB pattern formed on the panel can function as a pixel in the organic light-emitting display.

[0041] The metal plate (110) may be formed of an iron alloy containing iron and nickel, such as Invar. Additives such as aluminum and silicon may be added to remove impurities during the melting process for manufacturing the base material of the metal plate (110). The metal plate (110) may further include other components in addition to iron, nickel, and cobalt. The metal plate (110) may be manufactured through a rolling process and annealing process.

[0042] A plurality of effective areas (120) and ineffective areas (130) may be provided on the metal plate (110). The effective area (120) may be arranged in the central area of ​​the metal plate (110), and the ineffective area (130) may be arranged on the outer side of the metal plate (110) relative to the effective area (120). For example, four effective areas (210a, 210b, 210c, 210d) and four ineffective areas (220a, 220b, 230a, 230b) may be provided on the metal plate (110). Four valid areas (210a, 210b, 210c, 210d) may be arranged in the central area of ​​the metal plate (110), and two ineffective areas (220a, 230a) and two other ineffective areas (220b, 230b) may be arranged on either side thereof. However, the present invention is not limited thereto, and it is also possible for any one of the valid areas (120) and the ineffective areas (130) to be provided singly on the metal plate (110). Alternatively, it is also possible for both the valid areas (120) and the ineffective areas (130) to be provided singly on the metal plate (110).

[0043] When multiple effective areas (120) are provided on the metal plate (110), two adjacent effective areas may be spaced apart. For example, a spaced area may be formed between a first effective area (210a) and a second effective area (210b). A spaced area may be formed between a second effective area (210b) and a third effective area (210c). A spaced area may be formed between a third effective area (210c) and a fourth effective area (210d). The spaced area between two adjacent effective areas may be included in an ineffective area (130).

[0044] The effective area (120) is also called a cell region, and as illustrated in FIG. 2, a first groove (310), a second groove (320), etc. may be formed within the effective area (120). FIG. 2 is an exemplary diagram illustrating components formed within the effective area within a metal plate. The following description refers to FIG. 2.

[0045] A first groove (310) and a second groove (320) having different sizes may be formed on both sides of the metal plate (110), respectively. The first groove (310) may be formed by penetrating the first surface (110a) and the second surface (110b) of the metal plate (110). The first groove (310) may be a concave portion formed concavely in a direction from the first surface (110a) to the second surface (110b). The first surface (110a) may be either the upper surface or the lower surface of the metal plate (110). The second surface (110b) may be a surface different from the first surface (110a). The second surface (110b) may be another one of the upper surface and the lower surface of the metal plate (110).

[0046] The second groove (320) may be formed on the second surface (110b) of the metal plate (110). The second groove (320) may be connected to the first groove (310). The first groove (310) and the second groove (320) may be formed as through holes (330) in the metal plate (110) and may serve to pass an organic material in the direction in which the display panel is positioned so that the organic material may be deposited on the display panel.

[0047] The second groove (320) can be formed using a resist pattern and a plating layer (PL) formed on the second surface (110b). The second groove (320) can have a constant width in the depth direction (D3). The width (W2) of the second groove (320) can be smaller than the width (W1) of the first groove (310) on the first surface (110a) and can be the same as the width (W2) of the first groove (310) on the second surface (110b). The depth (H2) of the second groove (320) can be smaller than the depth (H1) of the first groove (310). The first groove (310) can be a large hole, and the second groove (320) can be a small hole.

[0048] The second surface (110b) on which the second groove (320) is formed may include a number of defects. As previously described, the metal plate (110) may be manufactured by rolling, and its surface or interior may include a number of inclusions. Here, the inclusions refer to particles or components other than iron, nickel, and cobalt contained in the metal plate (110). Therefore, during the process of manufacturing the metal plate (110), a number of defects such as scratches and dents may occur on the second surface (110b).

[0049] Referring to FIG. 3, three types of defects (410a, 410b, 410c), including a first defect (410a), a second defect (410b), and a third defect (410c), may occur on the second surface (110b). The first defect (410a) refers to a defect that occurs below the area (420a) where the second groove (320) is formed. The second defect (410b) refers to a defect that occurs within the area (420b) where the second groove (320) is not formed. The third defect (410c) refers to a defect that occurs across both the area (420a) where the second groove (320) is formed and the area (420b) where the second groove (320) is not formed. FIG. 3 is an exemplary diagram for explaining defects formed on the surface of a metal plate.

[0050] In the case of the first defect (410a), it occurs in the area (420a) where the second groove (320) is formed, and can be removed when forming the first groove (310). Referring to FIG. 4, the first defect (410a) may not change the size of the through hole (330) (W3). On the other hand, in the case of the third defect (410c), it occurs across the area (420a) where the second groove (320) is formed and the area (420b) where the second groove (320) is not formed, and a part of the third defect (410c) may not be removed when forming the first groove (310). Referring to FIG. 5, the third defect (410c) may change the size of the through hole (330) (W3 → W4 (>W3)). FIG. 4 is a first exemplary diagram for explaining a problem caused by a defect formed on the surface of a metal plate. Figure 5 is a second example diagram for explaining a problem caused by a defect formed on the surface of a metal plate.

[0051] Referring to FIG. 6, in order to solve the problem of defects formed on the second surface (110b) of the metal plate (110), a plating layer (430) may be formed on the second surface (110b). The plating layer (430) may be formed on the remaining area of ​​the second surface (110b) except for the area where the resist pattern (440a, 440b) is formed. That is, the plating layer (430) may not be formed on the area (420a) where the second groove (320) is formed, but may be formed on the area (420b) where the second groove (320) is not formed. The plating layer (430) may fill up the defects (410b, 410c) formed on the second surface (110b) with the plating portions (450a, 450b). The plating portion (450b) can partially fill the defect (410c), but can also completely fill the defect (410c). When the plating portions (450a, 450b) fill the defects (410b, 410c), the size of the through hole (330) formed in the metal plate (110) can be prevented from becoming uneven. Fig. 6 is an exemplary diagram illustrating a method for solving the problem of defects formed on the surface of the metal plate.

[0052] Since the defects (410a, 410b, 410c) generated during the process of manufacturing the metal plate (110) are randomly distributed over the entire area of ​​the metal plate (110), it is impossible to avoid the problematic defects (410b, 410c) and form a plurality of through holes (330) with a uniform size in the metal plate (110). If the sizes of the plurality of through holes (330) formed in the metal plate (110) are not uniform, the deposition mask (100) may become a defective product, and when the deposition mask (100) is mass-produced, the yield may decrease. Therefore, in the present invention, the problematic defects (410b, 410c) are filled with the plating portions (450a, 450b) using the plating layer (430), thereby allowing the sizes of the plurality of through holes (330) to be formed uniformly.

[0053] Meanwhile, the plating layer (430) may not be formed on the entire surface of the metal plate (110). The through holes used for organic material deposition in the deposition mask (100) are formed in the effective area (120) and are not formed in the non-effective area (130). Therefore, the plating layer (430) may be formed only in the effective area (120) of the metal plate (110) and may not be formed in the non-effective area (130) of the metal plate (110). In this case, defects (410b, 410c) existing in the effective area (120) may be filled with the plating portion (450a, 450b), and defects (410b, 410c) existing in the non-effective area (120) may not be filled with the plating portion (450a, 450b).

[0054] This is explained again with reference to Figure 1.

[0055] The non-effective area (130) is positioned in an area surrounding the effective area (120), and unlike the effective area (120), a through hole (330) is not formed. The non-effective area (130) may include a clamping area (220a, 220b) and a tension compensation area (230a, 230b).

[0056] The clamping region (220a, 220b) is a portion that is fastened to a clamp when the deposition mask (100) is tensioned and fastened to the mask frame. The clamping regions (220a, 220b) may be formed at each end of the metal plate (110) in the longitudinal direction (D1). The mask frame will be described later.

[0057] Although not shown in FIG. 1, the ineffective area (130) may further include a bonding area. The bonding area refers to a portion to be welded to the mask frame. The clamp may be fastened to the metal plate (110) through the clamping areas (220a, 220b) and may apply a tensile force in both ends of the metal plate (110). The metal plate (110) may be welded to the mask frame through the bonding area while the tensile force is applied in this manner. The bonding area may be provided between the clamping areas (220a, 220b) and the tension compensation areas (230a, 230b), but is not necessarily limited thereto. The clamping areas (220a, 220b) and the bonding area may be removed through a cutting process before the deposition mask (100) is utilized in an organic material deposition process.

[0058] The tensile compensation area (230a, 230b) is an area where a tensile compensation pattern is formed. When welding the mask frame while applying tensile force to the deposition mask (100), the tensile force may also affect the through hole (330) within the effective area (120). Therefore, in order to minimize the influence of the tensile force and prevent damage to the through hole (330), it is necessary to form a tensile compensation pattern in the ineffective area (130) to alleviate the tensile force affecting the through hole (330). The tensile compensation pattern may be formed by including a plurality of grooves.

[0059] The tension compensation region (230a, 230b) may be formed between the effective region (120) and the clamping region (220a, 220b). That is, the first tension compensation region (230a) may be formed between the first effective region (210a) and the first clamping region (220a). In addition, the second tension compensation region (230b) may be formed between the fourth effective region (210d) and the second clamping region (220b).

[0060] However, the present invention is not limited thereto, and the tension compensation regions (230a, 230b) may also be formed in a separation region between two adjacent effective regions. For example, the tension compensation regions (230a, 230b) may be formed in at least one of the separation regions among the separation region between the first effective region (210a) and the second effective region (210b), the separation region between the second effective region (210b) and the third effective region (210c), and the separation region between the third effective region (210c) and the fourth effective region (210d).

[0061] Hereinafter, a method for manufacturing a deposition mask (100) in which problematic defects (410b, 410c) are filled with plating portions (450a, 450b) will be described. Fig. 7 is a flowchart for sequentially explaining a method for manufacturing a deposition mask.

[0062] First, a metal plate (110) is prepared. The metal plate (110) may be prepared from an iron alloy containing iron and nickel. For example, the metal plate (110) may be prepared from Invar. The metal plate (110) may have a thickness of 10 μm to 50 μm. Preferably, the metal plate (110) may have a thickness of 15 μm to 30 μm.

[0063] Once the metal plate (110) is prepared, surface treatment is performed on the metal plate (110) (S510). When surface treatment is performed on the metal plate (110), both surfaces of the metal plate (110) may be surface treated. However, the present invention is not limited thereto, and surface treatment of only one surface of the metal plate (110) is also possible. For example, only the second surface (110b) on which the plating portions (450a, 450b) are formed may be surface treated.

[0064] When surface treating a metal plate (110), the metal plate (110) can be surface treated using a soft etching method. Using a soft etching method, contamination, impurities, or foreign substances distributed on the surface of the metal plate (110) can be removed, and plating adhesion can be improved. When using a soft etching method, the thickness of the plating layer (430) can be adjusted taking into account the thickness of the metal plate (110).

[0065] When surface treating a metal plate (110), the metal plate (110) may be surface treated using a chemical treatment method. When using a chemical treatment method, the entire surface or a portion of the metal plate (110) may be etched. When the metal plate (110) is a rolled substrate, the etching may be performed so that the thickness of the etched portion is 10 nm to 20 μm.

[0066] After surface treatment of the metal plate (110), resist is applied to both sides (110a, 110b) of the metal plate (110) (S520). Referring to Fig. 8, the resist (610a, 610b) may be a photosensitive resin material and may be a dry film resist (DFR). Alternatively, the resist (610a, 610b) may be a coating type photo resist. The resist (610a, 610b) formed on both sides (110a, 110b) of the metal plate (110) may be a negative resist. Fig. 8 is an exemplary diagram for explaining a resist application process in a method for manufacturing a deposition mask.

[0067] In the present invention, a film-type resist can be applied to both surfaces (110a, 110b) of a metal plate (110). However, the present invention is not limited thereto, and it is also possible to apply a liquid-type resist to both surfaces (110a, 110b) of the metal plate (110). When the liquid-type resist is applied to both surfaces (110a, 110b) of the metal plate (110), the liquid-type resist can partially cover the defects (410b, 410c) generated on the second surface (110b). The liquid-type resist can only cover the edge portions of the defects (410b, 410c) due to the tension of an air trap. On the other hand, when a film-type resist is applied to both surfaces (110a, 110b) of a metal plate (110), the film-type resist can completely cover the defects (410b, 410c) that have occurred on the second surface (110b). Therefore, the use of a film-type resist is advantageous in filling the defects that have occurred on the surface of the metal plate (110) and in securing straightness related to the defect filling.

[0068] When a film-type resist is applied to both surfaces (110a, 110b) of a metal plate (110), a protective film (615a, 615b) may be attached to each resist (610a, 610b). The first protective film (615a) and the second protective film (615b) serve to protect each resist (610a, 610b), and in the case of the first protective film (615a), the first surface (110a) where a large hole is to be formed may be protected in the step of forming a small hole. In the present invention, a separate protective layer forming process for protecting the large hole can be omitted in the step of forming the small hole through the first protective film (615a), and thus, the effect of reducing the number of processes can be obtained. For the convenience of explanation, the illustration of the protective films (615a, 615b) is omitted below.

[0069] This is explained again with reference to Figure 7.

[0070] After forming resists (610a, 610b) on both surfaces (110a, 110b) of a metal plate (110), an exposure process is performed on both surfaces (110a, 110b) of the metal plate (110) (S530). Next, a first development process is performed on the second surface (110b) of the metal plate (110) (S540). As described above, the second surface (110b) refers to the surface of the metal plate (110) on which the second groove (320) is formed. Specifically, the second protective film (615b) is removed on the second surface (110b), and then the first development process is performed on the corresponding resist (610b).

[0071] When the exposure process (S530) and the first development process (S540) are sequentially performed, a plurality of resist patterns remain in the portion where the second groove (320) is to be formed on the second surface (110b). Referring to FIG. 9, a first DFR pattern (620a) and a second DFR pattern (620b) may remain on the second surface (110b). A first defect (410a) may be formed adjacent to the first DFR pattern (620a). A third defect (410c) may be formed adjacent to the second DFR pattern (620b). A second defect (410b) may be formed in an area that is not adjacent to the first DFR pattern (620a) and the second DFR pattern (620b). FIG. 9 is an exemplary diagram for explaining the exposure process and the first development process in a method for manufacturing a deposition mask.

[0072] This is explained again with reference to Figure 7.

[0073] After performing the first development process (S540) on the second surface (110b), a plating layer (430) is formed on the second surface (110b) (S550). Referring to FIG. 10, the plating layer (430) may be formed on the remaining portion of the second surface (110b) except for the portion where the first DFR pattern (620a) and the second DFR pattern (620b) remain. The first plating portion (450a) may be filled in the entirety of the second defect (410b) based on the plating layer (430). The second plating portion (450b) may be filled in at least a portion of the third defect (410b) based on the plating layer (430). FIG. 10 is an exemplary diagram for explaining a plating process among methods for manufacturing a deposition mask.

[0074] The plating layer (430) may be formed on the second surface (110b) using an additive method. However, the present invention is not limited thereto, and the plating layer (430) may also be formed on the second surface (110b) using a subtractive method. The thickness of the plating layer (430) may be 4 μm or less, and accordingly, the step height (SH) may be 4 μm or less. Here, the step height refers to the depth (H2) of the second groove (320). Preferably, the thickness of the plating layer (430) may be 3 μm or less. The defect filling rate on the second surface (110b) by the plating layer (430) may be 50% or more and 100% or less. In addition, when depositing an organic material on a display panel, in order to secure the uniformity and shape quality of the deposited organic material, the boundary of the plating filling portion within the defect corresponding to the boundary of the second groove (320) may be ±1.5 ㎛ or less based on the boundary of the second groove (320).

[0075] The plating layer (430) may be formed using the same metal as the components constituting the metal plate (110). For example, the plating layer (430) may be formed using at least one metal selected from iron or nickel. However, the present invention is not limited thereto, and the plating layer (430) may be formed using a metal different from the components constituting the metal plate (110), as long as it is a metal that can secure bonding strength with the components constituting the metal plate (110), i.e., a metal that can have adhesion to the components constituting the metal plate (110).

[0076] When the metal plate (110) is a rolled substrate, the longitudinal coefficient of thermal expansion (CTE) of the metal plate (110) may be 1.5 ppm or less in the range of 25°C to 100°C. The coefficient of thermal expansion of the metal plate (110) including the plating layer (430) may be 2 ppm or less. The Rz and Ra of the metal plate (110) including the plating layer (430) may be 0.8 μm or less and 0.08 μm or less, respectively.

[0077] This is explained again with reference to Figure 7.

[0078] After performing the plating process (S550) to fill the second defect (410b) and the third defect (410c) with the first plating portion (450a) and the second plating portion (450b), a protective layer is formed on the plating layer (430) (S560). Referring to FIG. 11, the protective layer (630) may be formed in the form of a masking film to protect the plating layer (430) while leaving the first DFR pattern (620a) and the second DFR pattern (620b) on the second surface (110b). The protective layer (630) may cover the entire second surface (110b) including the first DFR pattern (620a) and the second DFR pattern (620b). However, the present invention is not limited thereto, and the protective layer (630) may also cover the remaining area of ​​the second surface (110b) except for the first DFR pattern (620a) and the second DFR pattern (620b). The protective layer (630) may be formed by applying a protective film to the second surface (110b). Fig. 11 is an exemplary diagram illustrating a protective layer forming process among the deposition mask manufacturing methods.

[0079] This is explained again with reference to Figure 7.

[0080] After forming a protective layer (630) on the plating layer (430), a second development process is performed on the first surface (110a) of the metal plate (110) (S570). Specifically, the first protective film (615a) is removed on the first surface (110a), and then a second development process is performed on the corresponding resist (610a). When the second development process (S570) is completed, a plurality of resist patterns remain on the first surface (110a), and the first groove (310) can be formed through a portion where the plurality of resist patterns are not formed (for example, an area between two different resist patterns). Referring to Fig. 12, a third DFR pattern (640a), a fourth DFR pattern (640b), and a fifth DFR pattern (640c) may remain on the first surface (110a) to form a first groove (310) that can be in contact with the first DFR pattern (620a) and the second DFR pattern (620b). Fig. 12 is a first exemplary diagram for explaining a second development process in a deposition mask manufacturing method.

[0081] Referring to FIG. 13a, the third DFR pattern (640a), the fourth DFR pattern (640b), and the fifth DFR pattern (640c) may be formed in a form in which the upper surface length (L1) thereof is shorter than the lower surface length (L2). However, the present invention is not limited thereto, and the third DFR pattern (640a), the fourth DFR pattern (640b), and the fifth DFR pattern (640c) may also be formed in a form in which the upper surface length (L1) thereof is the same as the lower surface length (L2) thereof, as illustrated in FIG. 13b. Alternatively, the third DFR pattern (640a), the fourth DFR pattern (640b), and the fifth DFR pattern (640c) may also be formed in a form in which the upper surface length (L1) thereof is longer than the lower surface length (L2) thereof, as illustrated in FIG. 13c. In the present invention, in order to expand the range of organic material deposition on the display panel through the through hole (330), the third DFR pattern (640a), the fourth DFR pattern (640b), and the fifth DFR pattern (640c) can be formed in a shape as illustrated in Fig. 13a. Fig. 13a is a second exemplary diagram for explaining the second development process in the deposition mask manufacturing method. Fig. 13b is a third exemplary diagram for explaining the second development process in the deposition mask manufacturing method. Fig. 13c is a fourth exemplary diagram for explaining the second development process in the deposition mask manufacturing method.

[0082] Meanwhile, it goes without saying that the two DFR patterns (620a, 620b) formed on the second surface (110b) may be formed in any one of the shapes illustrated in FIG. 13a, FIG. 13b, and FIG. 13c, similar to the three DFR patterns (640a, 640b, 640c) formed on the first surface (110a). Accordingly, the inclination of the inner wall of the second groove (320) may be 90 degrees or less with respect to the second surface (110b). Preferably, the inclination of the inner wall of the second groove (320) may be 60 to 90 degrees with respect to the second surface (110b).

[0083] This is explained again with reference to Figure 7.

[0084] After performing the second development process (S570), an etching process is performed (S580) considering the positions of the resist patterns (640a, 640b, 640c) remaining on the first surface (110a). The etching process may be performed using a photo etching method. Referring to FIG. 14, the area between the third DFR pattern (640a) and the fourth DFR pattern (640b) may be etched, and a first groove (310a) in contact with the first DFR pattern (620a) may be formed in the area. The first groove (310a) in contact with the first DFR pattern (620a) may remove the first defect (410a) from the second surface (110b) of the metal plate (110).

[0085] Similarly, the area between the fourth DFR pattern (640b) and the fifth DFR pattern (640c) can be etched, and a first groove (310b) in contact with the second DFR pattern (620b) can be formed in the area. The first groove (310b) in contact with the second DFR pattern (620b) can remove the third defect (410c) that is not filled with the second plating portion (450b) on the second surface (110b) of the metal plate (110). Fig. 14 is a first exemplary diagram for explaining an etching process in a method for manufacturing a deposition mask.

[0086] As described above, the plurality of first grooves (310a, 310b) may be formed concavely in the direction from the first surface (110a) to the second surface (110b). The plurality of first grooves (310a, 310b) may have a maximum width at the first surface (110a) and a minimum width at the second surface (110b). The example of Fig. 14 is an example in which the minimum widths of the plurality of first grooves (310a, 310b) are equal to the widths of the first DFR pattern (620a) and the second DFR pattern (620b). However, the present invention is not limited thereto, and the minimum widths of the plurality of first grooves (310a, 310b) may be formed to be larger than the widths of the first DFR pattern (620a) and the second DFR pattern (620b), as illustrated in Fig. 15. The minimum width of the plurality of first grooves (310a, 310b) may be sufficiently large to completely remove not only the first defect (410a) but also the third defect (410c). Fig. 15 is a second exemplary diagram illustrating an etching process among the deposition mask manufacturing methods.

[0087] Referring to FIG. 16, in the case of the first groove (310a) contacting the first DFR pattern (620a), one side portion (650a) contacting the second surface (110b) may be formed on the same line as the other side portion (650b). On the other hand, referring to FIG. 17, in the case of the first groove (310b) contacting the second DFR pattern (620b), one side portion (650c) contacting the second surface (110b) may not be formed on the same line as the other side portion (650d) due to the second plating portion (450b). That is, the other side portion (650d) may be formed higher than the one side portion (650c) due to the influence of the second plating portion (450b).

[0088] In the present invention, it is also possible to form the heights of one side portion (650c) and the other side portion (650d) differently as long as the required organic material deposition range is not limited for each through hole (330). Here, the difference value (DV) between the one side portion (650c) and the other side portion (650d) may not exceed a reference value. The reference value may be determined as an appropriate value as long as the organic material deposition range is not limited. The reference value may be determined in consideration of the thickness of the plating layer (430) and may be 4 μm or less. Fig. 16 is a third exemplary drawing for explaining an etching process in a method for manufacturing a deposition mask. Fig. 17 is a fourth exemplary drawing for explaining an etching process in a method for manufacturing a deposition mask.

[0089] This is explained again with reference to Figure 7.

[0090] After forming a plurality of first grooves (310a, 310b), a stripping process is performed on the first surface (110a) and the second surface (110b) (S590). Referring to FIG. 18, according to the stripping process (S590), the resist patterns (640a, 640b, 640c) remaining after the second developing process (S570), i.e., the third DFR pattern (640a), the fourth DFR pattern (640b), and the fifth DFR pattern (640c) can be removed from the first surface (110a). And, on the second surface (110b), the resist patterns (620a, 620b), that is, the first DFR pattern (620a) and the second DFR pattern (620b) and the protective layer (630) remaining after the first development process (S540) can be removed. In the present invention, the resist patterns (620a, 620b, 640a, 640b, 640c) and the protective layer (630) formed on the first surface (110a) and the second surface (110b) can be peeled off at once by the peeling process (S590). Fig. 18 is an exemplary diagram for explaining the peeling process in the method for manufacturing a deposition mask.

[0091] The deposition mask (100) manufactured according to the method described with reference to FIGS. 7 to 18 performs a coating process and an exposure process simultaneously on both sides of a metal plate (110), and then sequentially performs a development process on the small-pore surface (i.e., the second surface (110b)) and the large-pore surface (i.e., the first surface (110a)), additionally performs a plating process on the small-pore surface, and additionally performs an etching process on the large-pore surface, thereby forming a plurality of through holes (330) in the effective area (120) of the metal plate (110). The point where the large-pore surface and the small-pore surface meet may include a part filled with inclusions or defects during plating of the small-pore surface.

[0092] A groove-shaped half pattern may be formed on the second surface (110b) of the metal plate (110). The half pattern may be formed in the space between a specific through hole and another through hole. The half pattern may be formed in the space adjacent to each through hole. The depth of the half pattern may be 30% to 60% of the thickness of the metal plate (110).

[0093] When forming a through hole (330) in a metal plate (110), the longitudinal direction thereof may be processed in the same direction as the rolling direction. In addition, the width direction thereof may be processed so as to be perpendicular to the rolling direction. The metal plate (110) may have a surface contact angle of 65 degrees or less through surface treatment prior to plating. Preferably, the surface contact angle may be 45 degrees or more and 65 degrees or less.

[0094] In the present invention, a deposition mask (100) can be manufactured by applying a combination of an etching process and a plating process. When a second groove (320) is formed on a second surface (110b) of a metal plate (110) through a plating process, the second defect (410b) and the third defect (410c) are filled with a first plating portion (450a) and a second plating portion (450b) by a plating layer (430), and the first groove (310) is formed on the first surface (110a) of the metal plate (110) through an etching process, thereby manufacturing the deposition mask (100). When the deposition mask (100) is manufactured in this manner, both the second defect (410b) and the third defect (410c) generated on the second surface (110b) can be filled, and it becomes possible to form a plurality of through holes (330) with a uniform size in the deposition mask (100). Additionally, the deposition efficiency or deposition yield of the deposition mask (100) can also be improved.

[0095] Meanwhile, the first defect (410a), the second defect (410b), and the third defect (410c) may also occur on the first surface (110a). However, since the wide width of the first groove (310) is formed on the first surface (110a), the change in the size of the narrow width of the first groove (310) has no effect. Therefore, in the present invention, the second defect (410b) and the third defect (410c) can be filled with the first plating portion (450a) and the second plating portion (450b) limited to the second surface (110b).

[0096] To manufacture high-resolution organic light-emitting displays, the deposition process, which finely forms RGB pixels on the substrate, is crucial. However, a high step height during the deposition process can increase shadow distance, reducing process precision. Therefore, it is necessary to lower the step height, which can affect deposition yield.

[0097] When the blunt edge is lowered, the amount of etching on one or both sides of the metal plate (110) may increase, and the height of the through hole (330) may decrease. In addition, since the amount of metal per unit area decreases, a problem may arise in which the through hole (330) becomes defective even due to small inclusions. In other words, the defects of the through hole (330) due to the removal of inclusions may increase due to the decrease in the rigidity of the metal plate (110).

[0098] In the present invention, the plating layer (430) can be utilized to fill the defects that occur on the second surface (110b). Therefore, even if the etching amount in the metal plate (110) increases to lower the bump, the height of the through hole (330) can be prevented from decreasing due to the thickness of the plating layer (430). In addition, since the plating layer (430) can also fill all the inclusions that occur on the second surface (110b), the problem of the through hole (330) becoming defective due to the inclusions can also be improved. In the present invention, the influence of the inclusions can be minimized by the thickness of the plating layer (430), and a low and uniform bump can be realized. According to experimental results, the bump can be realized to 2㎛ or less, which can be reduced by 50% compared to conventional products.

[0099] When manufacturing a high-resolution organic light-emitting display having a resolution of 500 ppi or higher, the hole size uniformity of the through hole (330) needs to be increased and the CR (Corner-R) value needs to be decreased to increase deposition efficiency. However, in an etching process that performs etching with a chemical agent, increasing the hole size distribution and decreasing the CR value are limited due to the influences of the crystal grain size and orientation of the substrate, the surface condition of the substrate, the thickness distribution of the substrate, the difference in exposure resolution, and the difference in etching speed. This problem can be solved by processing the second surface (110b) of the metal plate (110) to a uniform thickness and shape using a plating process.

[0100] In the etching process, the hole size may change due to various factors such as the crystal structure of the metal plate (110), the surface condition of the metal plate (110), the etching speed, the exposure resolution, and the thickness distribution of the metal plate (110). On the other hand, in the plating process, since it is only affected by the exposure resolution, the hole size deviation can be minimized, and the hole size uniformity in the deposition mask (100) can be increased.

[0101] Furthermore, in the etching process, etching speeds can differ between straight and corner etching. Even with process design improvements, there are limits to minimizing this difference. Conversely, in the plating process, the shape of the resist pattern can be controlled, making it possible to minimize this difference in etching speeds.

[0102] In the present invention, by forming a second groove (320) by removing the remaining resist pattern after forming a plating layer (430) on the second surface (110b), the hole size uniformity of the through hole (330) can be increased and the CR (Corner-R) value can also be reduced. According to the experimental results, the hole size distribution range can be implemented to 1 ㎛ or less, preferably 0.5 ㎛ or less, which can be improved by 200% compared to the conventional product. According to the experimental results, the CR value can be reduced to 5 ㎛ or less, preferably 3.5 ㎛ or less, which can be reduced by 40% compared to the conventional product.

[0103] Next, a deposition mask assembly including a plurality of deposition masks (100) will be described. Fig. 19 is a first exemplary drawing for describing a deposition mask assembly including a deposition mask. And, Fig. 20 is a second exemplary drawing for describing a deposition mask assembly including a deposition mask.

[0104] Fig. 19 shows a plan view before the deposition mask (100) is assembled. And, Fig. 20 shows a plan view after the deposition mask (100) is assembled. Referring to Figs. 19 and 20, the deposition mask assembly (700) may be configured to include a deposition mask (100), a mask frame (710), and a support (720). In the present invention, the mask frame (710) and the support (720) may be defined as a mask support mechanism.

[0105] The deposition mask (100) can be fixed on the mask frame (710) via the support (720). The deposition mask (100) can be fixed on the mask frame (710) by welding. A plurality of deposition masks (100) can be fixed on the mask frame (710). For example, each deposition mask (100) can be installed in the longitudinal direction in the first direction (D1), and the plurality of deposition masks can be arranged in the second direction (D2).

[0106] The mask frame (710) may be configured to include a frame member composed of a plurality of parts and an opening (715) formed on the inside of the frame member. The frame member may include, for example, four parts (711, 712, 713, 714) including a first part (711), a second part (712), a third part (713), and a fourth part (714). The material constituting the mask frame (710) may be the same as the material of the metal plate (110) of the deposition mask (100). For example, the material constituting the mask frame (710) may be an iron alloy containing nickel.

[0107] The first part (711) and the second part (712) may face each other in the second direction (D2) with the opening (715) therebetween. The third part (713) and the fourth part (714) may face each other in the first direction (D1) with the opening (715) therebetween. The first part (711) and the second part (712) may extend in the first direction (D1). The third part (713) and the fourth part (714) may extend in the second direction (D2). The first part (711) and the second part (712) may be shorter in length than the third part (713) and the fourth part (714).

[0108] The ends of the support (720) may be fixed to the first part (711) and the second part (712). The ends of the deposition mask (100) may be fixed to the third part (713) and the fourth part (714). The support (720) may be longer than the deposition mask (100).

[0109] The support (720) may include a plurality of support members arranged in a first direction (D1). For example, the support (720) may include seven support members, including a first support member (721), a second support member (722), a third support member (723), a fourth support member (724), a fifth support member (725), a sixth support member (726), and a seventh support member (727). Each of the support members (721, 722, 723, 724, 725, 726, 727) may include one end that is fixed to a first portion (711) of the mask frame (710) and the other end that is fixed to a second portion (712) of the mask frame (710).

[0110] The first support member (721) can be closest to the middle position of the third part (713) and the fourth part (714) of the mask frame (710). The middle position of the third part (713) and the fourth part (714) refers to a position where the distance to the third part (713) and the distance to the fourth part (714) are equal in the first direction (D1).

[0111] The second support member (722) may be positioned closer to the third portion (713) than the first support member (721). The third support member (723) may be positioned closer to the fourth portion (714) than the first support member (721). The fourth support member (724) may be positioned closer to the third portion (713) than the second support member (722). The fifth support member (725) may be positioned closer to the fourth portion (714) than the third support member (723). The sixth support member (726) may be positioned closer to the third portion (713) than the fourth support member (724). The seventh support member (727) may be positioned closer to the fourth portion (714) than the fifth support member (725).

[0112] The plurality of support members of the support (720) may overlap with the surrounding area of ​​the deposition mask (100) when viewed in a plan view. In this case, the deposition material passing through the through hole (330) within the effective area (120) of the deposition mask (100) may be prevented from attaching to the support (720). The material constituting each support member of the support (720) may be the same as the material of the metal plate (110) of the deposition mask (100). For example, the material constituting each support member of the support (720) may be an iron alloy containing nickel.

[0113] Although embodiments of the present invention have been described with reference to the attached drawings, the present invention is not limited to the above embodiments, but can be manufactured in various different forms. Those skilled in the art to which the present invention pertains will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential characteristics of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

[0114] The present invention relates to a metal mask. The present invention can be utilized in manufacturing OLED displays.

Claims

1. A step of forming a resist on the first surface and the second surface of a metal plate; A step of leaving a plurality of first resist patterns on the second surface; A step of forming a plating layer on the remaining portion except for the portion where the first resist pattern remains; A step of leaving a plurality of second resist patterns on the first surface; A step of etching the remaining portion except for the portion where the second resist pattern remains; and A method for manufacturing a deposition mask, comprising a step of peeling off the first resist pattern and the second resist pattern.

2. In paragraph 1, The second surface includes groove-shaped defects, A method for manufacturing a deposition mask in which some of the above defects are filled with the plating layer.

3. In paragraph 1, A method for manufacturing a deposition mask, wherein a first groove is formed on the first surface by the etching, a second groove is formed on the second surface by the plating layer, and the first groove and the second groove overlap each other to form a through hole penetrating the metal plate.

4. In paragraph 3, A method for manufacturing a deposition mask, wherein the boundary surface of the plating filling portion of the defect corresponding to the boundary of the second groove is ±1.5㎛ or less based on the boundary of the second groove.

5. In paragraph 3, A method for manufacturing a deposition mask, wherein the size of the first groove is larger than the size of the second groove.

6. In paragraph 3, A method for manufacturing a deposition mask, wherein the width of a portion of the first groove that contacts the second groove is equal to or wider than the width of a portion of the second groove that contacts the first groove.

7. In paragraph 1, A method for manufacturing a deposition mask wherein the above plating layer is 1 ㎛ or more and 4 ㎛ or less.

8. In paragraph 6, A method for manufacturing a deposition mask, wherein one side of the portion in contact with the second groove in the first groove has a different height from the other side.

9. In paragraph 8, A method for manufacturing a deposition mask, wherein the height difference between the one side and the other side is 4㎛ or less.

10. In paragraph 1, A method for manufacturing a deposition mask, wherein the resist is formed on each of the first surface and the second surface, including a protective film.

11. In paragraph 1, A method for manufacturing a deposition mask, further comprising a step of simultaneously exposing the first surface and the second surface before leaving the first resist pattern.

12. In paragraph 1, The step of leaving the first resist pattern is: A step of removing a protective film on the resist formed on the second surface; and A method for manufacturing a deposition mask, comprising a step of developing a resist formed on the second surface.

13. In paragraph 1, The step of forming a plating layer on the second surface and then leaving the second resist pattern is as follows: A step of removing a protective film on the resist formed on the first surface; and A method for manufacturing a deposition mask, comprising a step of developing a resist formed on the first surface.

14. In paragraph 1, A method for manufacturing a deposition mask further comprising a step of surface treating the metal plate before applying the resist.

15. In paragraph 14, A method for manufacturing a deposition mask in which the thickness of the above plating layer varies depending on the thickness of the metal plate to be surface-treated.

16. In paragraph 1, A method for manufacturing a deposition mask further comprising a step of forming a protective layer on the plating layer.

17. In paragraph 16, A method for manufacturing a deposition mask in which the above peeling step peels the protective layer simultaneously with the first resist pattern and the second resist pattern.

18. In paragraph 1, A method for manufacturing a deposition mask, wherein the step of forming the resist comprises applying a film-type resist to the first surface and the second surface.

19. In paragraph 1, A method for manufacturing a deposition mask in which the plating layer is made of the same metal component as the metal plate.

20. In paragraph 1, A method for manufacturing a deposition mask in which one side of the second resist pattern has a different size from the other side.

21. In paragraph 20, The above surface is a surface that contacts the first surface, The above surface is the surface facing the above surface, A method for manufacturing a deposition mask in which the size of the above one side is larger than the size of the above other side.

22. In paragraph 1, The above metal plate is an invar metal of nickel and iron alloy, A method for manufacturing a deposition mask, wherein the plating layer comprises the same metal as the metal plate or another metal having adhesion to the metal plate.

23. A deposition mask manufactured by a manufacturing method according to any one of claims 1 to 22.

24. A metal plate having a first surface and a second surface defined; At least one first groove penetrating the first surface and the second surface; and A plating layer including a second groove corresponding to the first groove on the second surface, The second surface includes groove-shaped defects, Some of the above defects are filled by the deposition mask with the plating layer.

25. In paragraph 24, The above metal plate is an invar metal of nickel and iron alloy, A deposition mask in which the plating layer comprises the same metal as the metal plate or another metal having adhesion to the metal plate.

26. In paragraph 24, A deposition mask having a thickness of the metal plate of 10 ㎛ to 50 ㎛.

27. In paragraph 24, A deposition mask in which the inner wall of the second groove has an inclination of 60° to 90° with respect to the second surface.

28. In paragraph 24, The above plating layer is a deposition mask having a thickness of 1㎛ or more and 4㎛ or less.

29. Frame; A deposition mask according to any one of claims 24 to 28, disposed on the frame; and A deposition mask assembly comprising a support for securing the deposition mask to the frame.

30. In paragraph 29, The above deposition mask is a deposition mask assembly applied to manufacturing an organic light-emitting display.

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