Mask assembly and method of manufacturing the same

Abstract

The present invention relates to a mask assembly and a method of manufacturing the same. The method includes forming a unit mask including a mask pattern and a mesh frame including a conductive pattern disposed to correspond to the mask pattern, respectively, and disposing the unit mask and the mesh frame on a mask frame. Forming the unit mask and the mesh frame includes forming a polymer layer, a conductive layer, and a hard mask layer, forming a mask pattern layer including an etching pattern, and forming the unit mask and the mesh frame using the mask pattern layer.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2020-0181956, filed on December 23, 2020, and all benefits derived from that application, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments of the present invention relate to a mask assembly and a method of manufacturing the mask assembly. More specifically, embodiments of the present invention relate to a mask assembly having improved production yield and masking effect, and a method of manufacturing the mask assembly. Background Technology

[0004] The display panel comprises multiple pixels. Each pixel includes a driving element such as a transistor and a light-emitting element such as an organic light-emitting diode. The light-emitting element includes electrodes and a light-emitting pattern.

[0005] A light-emitting pattern is formed by patterning the light-emitting layer using a mask, and the mask pattern is defined by the mask. In recent years, technologies for materials and manufacturing methods for large-area masks have been developed to improve the production yield of display panels that include light-emitting patterns. Summary of the Invention

[0006] Embodiments of the present invention provide a mask assembly comprising a unit mask comprising a polymer material and a mesh frame comprising a conductive material.

[0007] Embodiments of the present invention provide a method for manufacturing a mask assembly.

[0008] Embodiments of the present invention provide a method for manufacturing a mask assembly. The manufacturing method includes: forming a unit mask including a plurality of mask patterns and a mesh frame including a plurality of conductive patterns respectively configured to correspond to the plurality of mask patterns; and disposing the unit mask and the mesh frame on the mask frame. Forming the unit mask and the mesh frame includes: forming a polymer layer on a substrate and forming a conductive layer on the polymer layer. Forming the unit mask and the mesh frame further includes: forming a hard mask layer on the conductive layer, and etching the hard mask layer and the conductive layer to form a mask pattern layer including etched patterns. Forming the unit mask and the mesh frame further includes: etching the polymer layer using the mask pattern layer to form the unit mask and the mesh frame.

[0009] In an embodiment, the polymer layer may include a first polymer material, the hard mask layer may include a second polymer material, and the second polymer material may be different from the first polymer material.

[0010] In an embodiment, forming the cell mask and mesh frame may further include: partially removing the mask pattern layer to form the mesh frame, and separating the substrate from the cell mask.

[0011] In an embodiment, the mask pattern layer may include a first pattern layer formed by etching a hard mask layer and a second pattern layer formed by etching a conductive layer.

[0012] In one embodiment, etching the polymer layer may be performed using a first gas that selectively etches the polymer layer within the first patterned layer and the polymer layer. In another embodiment, the first gas selectively etches the polymer layer within the first patterned layer, the second patterned layer, and the polymer layer.

[0013] In an embodiment, partially removing the mask pattern layer may include removing the first pattern layer from the mask pattern layer using a second gas that selectively etches the first pattern layer between a first pattern layer and a second pattern layer.

[0014] In an embodiment, the second gas can selectively etch the first patterned layer among the cell mask, the first patterned layer, and the second patterned layer.

[0015] In an embodiment, forming the unit mask and mesh frame may further include: coating a photoresist on a hard mask layer and patterning the photoresist to form an etch mask.

[0016] In an embodiment, the etching pattern may include a plurality of first patterns provided in a first pattern layer and a plurality of second patterns provided in a second pattern layer.

[0017] In an embodiment, forming a mask pattern layer may include: etching a hard mask layer using an etch mask to form a first pattern layer comprising a plurality of first patterns, and etching a conductive layer using the first pattern layer to form a second pattern layer comprising a plurality of second patterns.

[0018] In an embodiment, forming the unit mask and mesh frame may further include removing the etch mask after forming the first pattern layer.

[0019] In one embodiment, etching the hard mask layer may include etching the hard mask layer using gas.

[0020] In one embodiment, the gas can selectively etch the hard mask layer within the hard mask layer and the conductive layer.

[0021] In an embodiment, etching the conductive layer may be performed using an etchant that selectively etches the conductive layer among the first patterned layer, the conductive layer, and the polymer layer.

[0022] In an embodiment, forming a unit mask and a mesh frame may further include etching a plurality of second patterns after forming the unit mask to form a conductive pattern.

[0023] In an embodiment, etching a plurality of second patterns may include: etching a plurality of second patterns included in a second pattern layer using an etchant that selectively etches the second pattern layer within a first pattern layer, a second pattern layer, and a unit mask.

[0024] Embodiments of the present invention provide a mask assembly comprising a mask frame including an outer frame through which a cell opening is defined; and a cell mask disposed on the mask frame and including a plurality of mask patterns configured to correspond to the cell opening and comprising a polymer material. The mask assembly further includes a mesh frame disposed between the mask frame and the cell mask, and including a plurality of conductive patterns configured to correspond to the plurality of mask patterns respectively and comprising a conductive material. The width of each of the plurality of mask patterns decreases continuously as the distance to a corresponding conductive pattern among the plurality of conductive patterns decreases.

[0025] In an embodiment, each of the plurality of conductive patterns may include a first surface in contact with a corresponding mask pattern among the plurality of mask patterns and a second surface opposite to the first surface. The first surface may have a width equal to or less than the width of each of the plurality of mask patterns, and the second surface may have a width smaller than the width of the first surface.

[0026] In an embodiment, each of the plurality of conductive patterns may further include a side surface portion connecting the first surface and the second surface, and the side surface portion may have a curved surface shape.

[0027] In the embodiments, the mesh frame may include a metallic material or a transparent conductive oxide, and the cell mask may include polyimide.

[0028] Based on the above, since the mesh frame is positioned on the cell mask, it prevents the mask assembly from sagging due to gravity during the deposition process. Specifically, the mesh frame is formed using a hard mask layer and photoresist used to form the cell mask. Therefore, the manufacturing process of the mask assembly is simplified, and the manufacturing time is reduced. Attached Figure Description

[0029] The above and other advantages of the invention will become apparent when considered in conjunction with the accompanying drawings, and by referring to the following detailed description, in which:

[0030] Figure 1 This is a perspective view illustrating an embodiment of a mask assembly according to the present invention;

[0031] Figure 2 This is an exploded perspective view showing an embodiment of a mask assembly according to the present invention;

[0032] Figure 3 It is along Figure 1 The line I-I' is cut off to show a cross-sectional view of the mask assembly;

[0033] Figure 4 This is a cross-sectional view showing an embodiment of a deposition apparatus according to the present invention;

[0034] Figure 5 This is a view illustrating an embodiment of a process for forming a polymer layer, a conductive layer, and a hard mask layer on a substrate according to the present invention;

[0035] Figure 6 This is a view illustrating an embodiment of a process for coating photoresist on a hard mask layer according to the present invention;

[0036] Figure 7 This is a view illustrating an embodiment of a process for patterning photoresist to form an etch mask according to the present invention;

[0037] Figure 8 This is a view illustrating an embodiment of the process for forming a first patterned layer using an etched mask according to the present invention;

[0038] Figure 9 This is a view illustrating an embodiment of the process for removing an etched mask according to the present invention;

[0039] Figure 10 This is a view illustrating an embodiment of the process for forming a second pattern layer using a first pattern layer according to the present invention;

[0040] Figure 11 This is a view illustrating an embodiment of a process for forming a unit mask using a mask pattern layer according to the present invention;

[0041] Figure 12 This is a view illustrating an embodiment of the process of etching a second pattern to form a conductive pattern according to the present invention;

[0042] Figure 13 This is a view illustrating an embodiment of a process according to the invention of partially removing a mask pattern layer to form a mesh frame; and

[0043] Figure 14 This is a view illustrating an embodiment of the process for separating a substrate from a cell mask according to the present invention. Detailed Implementation

[0044] In this disclosure, it will be understood that when an element or layer is referred to as being “on”, “connected to” or “coupled to” another element or layer, the element or layer may be directly on, directly connected to or coupled to the other element or layer, or there may be an intermediary element or layer.

[0045] The same reference numerals always refer to the same elements. In the drawings, the thickness, scale, and dimensions of parts are exaggerated for the purpose of effective description of the technical content.

[0046] As used herein, the term “and / or” includes any and all combinations of one or more of the items listed.

[0047] It will be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. Thus, the first element discussed below may be referred to as the second element without departing from the teachings of this disclosure. As used herein, the singular forms “a” and “the (described)” are intended to also include the plural forms, unless the context clearly indicates otherwise.

[0048] For ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” and “up” may be used in this document to describe the relationship between one element or feature as illustrated in the accompanying drawings and another element(s).

[0049] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will be further understood that terms such as those defined in common dictionaries shall be interpreted as having meanings consistent with their meanings in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless specifically limited thereto herein.

[0050] It will be further understood that, when used in this specification, the terms “comprising” and / or “including” specify the presence of the stated features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or groups thereof.

[0051] The mask and mask assembly will be explained in detail below with reference to the accompanying drawings.

[0052] Figure 1 This is a perspective view showing an embodiment of the mask assembly MKA according to the present invention, and Figure 2 This is an exploded perspective view showing an embodiment of the mask assembly MKA according to the present invention.

[0053] refer to Figure 1 and Figure 2 The mask assembly MKA can be used in the manufacturing process of a display device. Specifically, the mask assembly MKA can be used in a process of forming a pattern on a substrate during the manufacturing of a display device. In an embodiment, the pattern can be a light-emitting pattern included in a light-emitting element. The light-emitting element can be an organic light-emitting diode (OLED), and the light-emitting pattern can be an organic light-emitting pattern of the OLED.

[0054] The mask assembly MKA may have a cuboid shape. In an embodiment, the mask assembly MKA may include two long sides extending in a first direction DR1 and two short sides extending in a second direction DR2. The second direction DR2 indicates a direction intersecting the first direction DR1. In an embodiment, the second direction DR2 may be substantially perpendicular to the first direction DR1.

[0055] The mask assembly MKA can be a plate having a thin thickness on a third direction DR3. The third direction DR3 can indicate a direction that intersects substantially perpendicularly with the plane defined by the first direction DR1 and the second direction DR2. In the following description, the expression "in a plan view" can mean the state viewed on the third direction DR3.

[0056] The mask assembly MKA may include a mask frame MF, a unit mask CMK, and a mesh frame MSF. The mask frame MF may include a metallic material such as stainless steel (“SUS”), Invar alloy, nickel (Ni), or cobalt (Co). In embodiments, the mask frame MF may include, for example, Invar alloy. However, the material of the mask frame MF should not be limited thereto or thereby restricted. In embodiments, the mask frame MF may include a polyimide material to reduce the weight of the mask assembly MKA.

[0057] The unit mask CMK may include a polymer material. In an embodiment, the unit mask CMK may include polyimide. In an embodiment, when the unit mask CMK includes polyimide, the mask assembly MKA is lighter than when the unit mask CMK includes a metallic material. Accordingly, during the process of depositing patterns for a display device, the mask assembly MKA can be prevented from sagging due to its weight and gravity.

[0058] The mask frame MF may have a quadrilateral (e.g., rectangular) shape defined by a long side extending in a first direction DR1 and a short side extending in a second direction DR2. The mask frame MF may include an outer frame OF and may be provided with a cell opening COP defined to pass through the outer frame OF. In a plan view, the cell opening COP may have a quadrilateral (e.g., rectangular) shape. The cell opening COP may be defined to pass through the mask frame MF in a third direction DR3. The shape of the cell mask CMK may be modified to correspond to the shape of the cell opening COP. That is, when the cell opening COP has a quadrilateral (e.g., rectangular) shape, the cell mask CMK may also have a quadrilateral (e.g., rectangular) shape. In a plan view, the cell mask CMK may overlap with the cell opening COP.

[0059] A unit mask CMK may include mask portions MP and bonding portions BP. The mask portion MP may include multiple deposition portions EVP and non-deposition portions NEVP adjacent to the deposition portions EVP. Each deposition portion EVP may be provided with a mask pattern MPT (see reference). Figure 3 The mask pattern MPT can be formed or provided by partially removing the cell mask CMK along the third direction DR3. (See reference...) Figures 5 to 14 Describe in detail the process of forming the mask pattern MPT.

[0060] The bonding portion BP can extend from the mask portion MP. The bonding portion BP can extend from the mask portion MP in either a first direction DR1 or a second direction DR2. In a plan view, the bonding portion BP can have a quadrilateral annular shape and can be positioned along the edge of the mask portion MP.

[0061] In the plan view, the dimensions of the mask portion MP of the element mask CMK can be approximately the same as the dimensions of the element opening COP. The bonding portion BP of the element mask CMK can be set on the outer frame OF of the mask frame MF.

[0062] A unit mask CMK can be fixed to a mask frame MF. In an embodiment, for example, the bonding portion BP of the unit mask CMK can be fixed to a corresponding portion of the outer frame OF. In an embodiment, for example, a welding process can be performed between the outer frame OF and the corresponding bonding portion BP to fix the unit mask CMK to the mask frame MF. In this case, the unit mask CMK may include a polymer material. If the bonding portion BP of the unit mask CMK, which includes a polymer material, is directly welded to the outer frame OF, the unit mask CMK may be damaged. Accordingly, a protective layer can be provided on the bonding portion BP of the unit mask CMK to prevent the unit mask CMK from being damaged during the welding process.

[0063] Figure 2 A single cell opening (COP) is shown; however, this is merely an example, and the number of cell openings (COPs) can be greater than one. In an embodiment, the mask frame MF can be provided with a plurality of cell openings arranged and spaced apart from each other in at least one of the first direction DR1 and the second direction DR2. The cell openings can be arranged in a matrix along the first direction DR1 and the second direction DR2. The mask assembly MKA can include cell masks corresponding to the cell openings respectively. Each cell mask can include a deposited portion in which a mask pattern is provided and a non-deposited portion extending from the deposited portion.

[0064] A mesh frame (MSF) can be disposed between a mask frame (MF) and a cell mask (CMK). The mesh frame (MSF) can have a shape corresponding to the shape of the cell mask (CMK). The mesh frame (MSF) can include multiple conductive patterns (CPTs) disposed corresponding to the mask pattern (MPT) of the cell mask (CMK). Figure 3 The mesh frame MSF may comprise a metallic material or a transparent conductive oxide. In embodiments, the mesh frame MSF may comprise SUS, Invar alloy, indium tin oxide (“ITO”), or indium zinc oxide (“IZO”). In embodiments, the mesh frame MSF may have a shape corresponding to the entire deposition portion EVP of the cell mask CMK. Furthermore, the mesh frame MSF may comprise multiple sub-mesh frames, each corresponding to a deposition portion EVP of the cell mask CMK.

[0065] Figure 3 It is along Figure 1 The line I-I' is cut off to show a cross-sectional view of the mask assembly MKA.

[0066] refer to Figure 3 The mask component MKA may include a mask frame MF, a mesh frame MSF disposed on the mask frame MF, and a cell mask CMK disposed on the mesh frame MSF.

[0067] The cell mask CMK may include a mask pattern MPT, and multiple holes HL may be defined between the mask patterns MPT. The mesh frame MSF may include a conductive pattern CPT configured to correspond to the mask pattern MPT.

[0068] The mask component MKA may include a first region AR1, a second region AR2, and a third region AR3.

[0069] The first region AR1 can be defined in which the cell mask CMK and the mesh frame MSF are set in the outer frame OF of the mask frame MF (reference). Figure 2 The second region AR2 can be defined as the non-deposited portion NEVP (refer to) within which the mask portion MP is disposed. Figure 2 The third region AR3 can be defined as the region corresponding to the deposition portion EVP (reference) included in the mask portion MP, where the mask portion MP is located. Figure 2 The region corresponding to the area of ​​the first region AR1 and the region corresponding to the conductive pattern CPT can be formed or provided in the third region AR3. The mesh frame MSF may include a dummy conductive pattern DCPT set in the first region AR1 and the second region AR2 and corresponding to the cell mask CMK.

[0070] Each conductive pattern CPT in the conductive pattern CPT may have a width equal to or less than the width MPW of the surface of the corresponding mask pattern MPT that contacts the conductive pattern CPT. In an embodiment, each conductive pattern CPT may include a first surface FS1 that contacts the corresponding mask pattern MPT and a second surface FS2 that opposes the first surface FS1. The second surface FS2 may have a width FSW2 equal to or less than the width FSW1 of the first surface FS1. Accordingly, the conductive pattern CPT may not overlap with the aperture HL defined to pass through the unit mask CMK. In an embodiment, each conductive pattern CPT in the conductive pattern CPT may further include a side surface portion CV connecting the first surface FS1 and the second surface FS2. The side surface portion CV may have a curved surface shape.

[0071] In an embodiment, the width MPW of the mask pattern MPT can be continuously varied along the third direction DR3. Refer to the description below. Figure 11 The mask pattern MPT can be obtained by dry etching of the polymer layer PL (reference). Figure 5 The process is used to form or provide the mask pattern MPT. The width MPW of each mask pattern MPT can be continuously reduced as the distance along the third direction DR3 of the corresponding conductive pattern CPT in the conductive pattern CPT decreases.

[0072] Figure 4 This is a cross-sectional view showing an embodiment of the deposition apparatus DPD according to the present invention.

[0073] refer to Figure 3 and Figure 4 The deposition apparatus (DPD) may include a chamber (CHB), a deposition source (ES), a stage (STG), a moving plate (PP), and a mask assembly (MKA).

[0074] The chamber CHB can provide a sealed space. A movable plate PP, a deposition source ES, a stage STG, and a mask assembly MKA can be disposed within the chamber CHB. The chamber CHB may include at least one door GT. The chamber CHB can be opened and closed via the door GT. A target substrate SUB can be loaded into or unloaded from the chamber CHB via the door GT, which is formed or provided to pass through the chamber CHB.

[0075] The movable plate PP can be aligned with the target substrate SUB on the mask assembly MKA. The movable plate PP can move up and down or left and right. The movable plate PP can be provided with components for moving the target substrate SUB and components for holding the target substrate SUB.

[0076] The deposition source ES may include a deposition material. In this case, the deposition material is a sublimable or evaporable material and may include at least one of inorganic, metallic, and organic materials. The deposition source ES in the illustrated embodiment will be described as including an organic material used to manufacture organic light-emitting elements.

[0077] The stage STG can be positioned above the deposition source ES. The mask assembly MKA can be positioned on the stage STG. The mask assembly MKA can be positioned on the stage STG after being manufactured using a mask assembly fabrication process, as will be described later. The mask assembly MKA can face the deposition source ES. The stage STG can be configured to overlap with the mask frame MF of the mask assembly MKA and can support the mask assembly MKA. The stage STG can be separate from the mask portion MP of the unit mask CMK (see reference). Figure 2 The stage STG may not overlap with the deposition portion EVP of the element mask CMK (see reference). Figure 2 Overlap. That is, the stage STG may not overlap with the path through which the deposited material is supplied from the deposition source ES to the target substrate SUB.

[0078] The target substrate SUB can be disposed on the mask assembly MKA. Deposition material can be deposited on the target substrate SUB through apertures HL defined to pass through the unit mask CMK to form multiple patterns on the target substrate SUB. In an embodiment, the patterns can be light-emitting patterns of organic light-emitting elements.

[0079] In the process of depositing luminescent patterns for display devices using DPD deposition equipment, a bottom-up deposition method is mainly used. In this method, the target substrate SUB is placed at the top and the deposition material is deposited from the bottom to the top. In this case, when the portion of the mask assembly MKA that does not overlap with and is not supported by the stage STG sags due to gravity, it is necessary to prevent a gap from forming between the mask assembly MKA and the target substrate SUB. If the mask assembly MKA includes a magnetizable material such as a metal, a gap can be prevented by placing a magnet inside or on top of the moving plate PP to create a magnetic field.

[0080] However, in embodiments of the present invention where the unit mask CMK comprises a polymer material, the unit mask CMK is unresponsive to a magnetic field, and therefore, it is difficult to prevent the definition of a gap between the unit mask CMK and the target substrate SUB. In an embodiment, a mesh frame MSF comprising a conductive material may be disposed between the mask frame MF and the unit mask CMK.

[0081] When the mesh frame MSF responds to and is magnetized by a magnetic field, the mesh frame MSF and the target substrate SUB can be in close contact with each other, with no gap between the cell mask CMK and the target substrate SUB. In an embodiment, when the mesh frame MSF includes a conductive pattern CPT configured to correspond to the mask pattern MPT included in the cell mask CMK, no gap is provided between the deposition portion EVP of the cell mask CMK and the target substrate SUB. Accordingly, misalignment of the luminescent pattern caused by the gap appearing between the cell mask CMK and the target substrate SUB, and shading effects caused by interference with the movement of the deposited material towards the target substrate SUB, can be reduced.

[0082] Additionally, as an example, when the width of each conductive pattern CPT is equal to or less than the width MPW of the corresponding mask pattern MPT, the mesh frame MSF may not be positioned on the path from the deposition source ES to the target substrate SUB via the aperture HL. Therefore, although the mesh frame MSF is configured to prevent the definition of a gap between the cell mask CMK and the target substrate SUB, the deposition material can be deposited at predetermined locations on the target substrate SUB without being blocked by the mesh frame MSF.

[0083] After the deposition material is deposited on the target substrate SUB using the deposition apparatus DPD, the target substrate SUB can be separated from the mask assembly MKA. The initial substrate separated from the mask assembly MKA can correspond to the state in which a light-emitting pattern layer is formed on the target substrate SUB. The light-emitting pattern layers can be formed to correspond to the deposition portions EVP of the mask assembly MKA, respectively. Each light-emitting pattern layer can include multiple light-emitting patterns. A display device including organic light-emitting elements can then be manufactured using the initial substrate.

[0084] In the following text, reference will be made to Figures 5 to 14 Describe the method for manufacturing the mask assembly MKA.

[0085] Figure 5 This is a view illustrating an embodiment of the process for forming a polymer layer PL, a conductive layer CL, and a hard mask layer HML on a substrate according to the present invention.

[0086] refer to Figure 3 A method for manufacturing a mask assembly MKA may include: forming a cell mask CMK including a mask pattern MPT, and forming a mesh frame MSF including a conductive pattern CPT configured to correspond to the mask pattern MPT. The method for manufacturing the mask assembly MKA may further include: disposing the cell mask CMK and the mesh frame MSF on the mask frame MF.

[0087] refer to Figure 5 The formation of the unit mask CMK and the mesh frame MSF may include: forming a polymer layer PL on the substrate BS, forming a conductive layer CL on the polymer layer PL, and forming a hard mask layer HML on the conductive layer CL.

[0088] In an embodiment, the substrate BS may include glass, plastic, ceramic, or metallic materials. The polymer layer PL may include a first polymer material. The polymer layer PL may be formed by coating the substrate BS with the first polymer material. In an embodiment, the first polymer material may include polyimide.

[0089] The conductive layer CL can be formed by depositing a conductive material on the polymer layer PL. In an embodiment, the conductive layer CL can be formed by depositing a conductive material on the polymer layer PL using a sputtering process. In an embodiment, the conductive layer CL can include a metallic material or a transparent conductive oxide. The conductive layer CL can include SUS, Invar alloy, ITO, or IZO, etc.

[0090] The hard mask layer HML can be a layer that masks the conductive layer CL and the polymer layer PL. In an embodiment, the hard mask layer HML may include a second polymer material. The hard mask layer HML can be formed by coating the conductive layer CL with the second polymer material. The first polymer material and the second polymer material may include materials that are different from each other. In an embodiment, the second polymer material may include silicon nitride, silicon oxide, or amorphous silicon (a-Si), etc. However, the hard mask layer HML may include a metallic material or a transparent conductive oxide. In this case, the hard mask layer HML can be formed by depositing a metallic material or a transparent conductive oxide on the conductive layer CL using a sputtering process.

[0091] Figure 6 This is a view illustrating an embodiment of the process of coating photoresist PR on a hard mask layer HML according to the present invention, and Figure 7 This is a view illustrating an embodiment of a process for patterning photoresist PR to form an etch mask EM according to the present invention.

[0092] refer to Figure 6 and Figure 7 Forming a unit mask CMK (reference) Figure 2 ) and Grid Frame MSF (Reference) Figure 2 It may further include: coating a photoresist PR on a hard mask layer HML and patterning the photoresist PR to form an etch mask EM.

[0093] The photoresist (PR) can include a photosensitive material with properties that change in response to light, and the photoresist (PR) can have different properties in light-receiving and light-non-receiving portions. Accordingly, after a partially open light-shielding layer is formed on the photoresist (PR), during an exposure process that irradiates light onto the photoresist (PR), the portions of the photoresist (PR) not covered by the light-shielding layer can be exposed to light. The exposed portions can then be developed, and thus an etch mask (EM) can be formed.

[0094] In an embodiment, the etched mask EM may include an etch pattern to etch the hard mask layer HML, which will be described later.

[0095] Figure 8 This is a view illustrating an embodiment of the process for forming a first pattern layer PTL1 using an etched mask EM according to the present invention. Figure 9 This is a view illustrating an embodiment of the process for removing the etched mask EM according to the present invention, and Figure 10 This is a view illustrating an embodiment of the process for forming a second pattern layer PTL2 using a first pattern layer PTL1 according to the present invention.

[0096] refer to Figures 8 to 10 Forming a unit mask CMK (reference) Figure 2 ) and Grid Frame MSF (Reference) Figure 2 It may further include: forming a mask pattern layer MPL that includes an etched pattern ETP.

[0097] Mask patterning layer MPL can include hard mask layer HML (reference) by etching. Figure 7 The first pattern layer PTL1 is formed by etching the conductive layer CL, and the second pattern layer PTL2 is formed by etching the conductive layer CL. The etched pattern ETP may include a plurality of first patterns PT1 provided in the first pattern layer PTL1 and a plurality of second patterns PT2 provided in the second pattern layer PTL2.

[0098] The hard mask layer HML can be etched using an etch mask EM to form a first patterned layer PTL1 including a first pattern PT1. In an embodiment, the hard mask layer HML can be etched using a second gas. The second gas can be a gas that selectively etches the hard mask layer HML between the hard mask layer HML and the conductive layer CL. In an embodiment, the second gas can be a fluorine-based gas. The hard mask layer HML can also be etched using a second gas in a plasma state.

[0099] In an embodiment, where the hard mask layer HML includes silicon nitride, silicon oxide, or amorphous silicon (a-Si) and the conductive layer CL includes SUS, Invar alloy, ITO, or IZO, the second gas can selectively etch only the hard mask layer HML within the hard mask layer HML and the conductive layer CL.

[0100] The etch mask EM can be removed after the first patterned layer PTL1 is formed. In an alternative embodiment, the etch mask EM can be removed after a second patterned layer PTL2 is formed using the first patterned layer PTL1. The conductive layer CL can be etched using the first patterned layer PTL1 to form a second patterned layer PTL2 including the second pattern PT2.

[0101] In an embodiment, an etchant can be used to etch the conductive layer CL, selectively etching only the conductive layer CL among the first patterned layer PTL1, the conductive layer CL, and the polymer layer PL. The conductive layer CL can be wet-etched with the etchant to be isotropically etched. When the conductive layer CL is etched by a wet etching process, the side surfaces of each of the second patterns PT2 in the second patterns PT2 can have a curved shape. Furthermore, it is possible that the second patterns PT2 are undercut more than the first patterns PT1.

[0102] When the first patterning layer PTL1 is used to etch the conductive layer CL, it is not necessary to separately coat the photoresist and pattern the coated photoresist to etch the conductive layer CL. Accordingly, the manufacturing process time of the mask assembly MKA can be shortened, and the manufacturing process can be simplified.

[0103] Figure 11 This is a view illustrating an embodiment of a process using a mask pattern layer MPL forming unit mask CMK according to the present invention.

[0104] refer to Figure 11 This forms the cell mask (CMK) and mesh frame (MSF) (see reference). Figure 2 It may further include: using a mask pattern layer MPL to form a cell mask CMK including a mask pattern MPT.

[0105] In this embodiment, a mask patterning layer MPL can be used to etch the polymer layer PL (reference). Figure 10 This forms a cell mask CMK. In an embodiment, the polymer layer PL can be etched using a first gas that selectively etches only the polymer layer PL within the first patterning layer PTL1 and the polymer layer PL. In an embodiment, the first gas can be an oxygen-based gas. The polymer layer PL can be etched using the first gas in a plasma state.

[0106] In an embodiment, where the polymer layer PL comprises polyimide and the first patterning layer PTL1 comprises silicon nitride, silicon oxide, or amorphous silicon (a-Si), the first gas can selectively etch the polymer layer PL within the first patterning layer PTL1 and the polymer layer PL. In another embodiment, the first gas can selectively etch only the polymer layer PL within the polymer layer PL, the first patterning layer PTL1, and the second patterning layer PTL2.

[0107] In this embodiment, the polymer layer PL can have a thickness of several micrometers to tens of micrometers. Accordingly, when the polymer layer PL is etched using a first gas dry etching process, a phenomenon may occur in which the mask pattern MPT is etched with more undercut material than the second pattern PT2. In this case, the second pattern PT2 may have a width PTW greater than the width MPW of the mask pattern MPT.

[0108] Figure 12 This is a view illustrating an embodiment of the process of etching a second pattern PT2 to form a conductive pattern CPT according to the present invention.

[0109] refer to Figure 12 This forms the cell mask (CMK) and mesh frame (MSF) (see reference). Figure 2 This may further include: etching a second pattern PT2 after forming the unit mask CMK (see reference). Figure 11 To form a conductive pattern CPT.

[0110] The second pattern PT2 can be etched using an etchant that selectively etches only the second pattern layer PTL2 within the first pattern layer PTL1, the second pattern layer PTL2, and the cell mask CMK. In an embodiment, the etchant used to etch the second pattern PT2 may include the same etchant used to etch the conductive layer CL (refer to...). Figure 9 The etchant is made of the same material.

[0111] The second pattern PT2 can be wet-etched with an etchant to be isotropically etched. The conductive pattern CPT may include a side surface portion CV. In an embodiment, the side surface portion CV may have a curved surface shape. The mask pattern MPT included in the unit mask CMK may not be etched simultaneously with the second pattern PT2. Accordingly, the conductive pattern CPT may have a width equal to or less than the width MPW of the mask pattern MPT. In an embodiment, the second surface FS2 (refer to...) is included in each conductive pattern CPT. Figure 3 The width of the first surface FS1 (refer to the width of the mask pattern MPT) can be smaller than the width of the mask pattern MPT, MPW. Figure 3 The width FSW1 of the first surface FS1 can be the same as the width MPW of the mask pattern MPT. However, in an embodiment, the width FSW1 of the first surface FS1 can be smaller than the width MPW of the mask pattern MPT.

[0112] Figure 13 This is a view illustrating an embodiment of a process according to the present invention of partially removing the mask pattern layer MPL to form a mesh frame MSF.

[0113] refer to Figure 13 The formation of the unit mask (CMK) and mesh frame (MSF) may further include: partially removing the mask pattern layer (MPL) (see reference). Figure 12 To form a mesh frame (MSF).

[0114] It can be used in the first pattern layer PTL1 (reference) Figure 12 ) and the second patterned layer PTL2 (reference) Figure 12 A second gas is used to selectively etch the first patterned layer PTL1 within the mask patterned layer MPL to partially remove the mask patterned layer MPL. The mesh frame MSF can be formed by removing the first patterned layer PTL1 from the mask patterned layer MPL. The second gas can selectively etch only the first patterned layer PTL1 within the cell mask CMK, the first patterned layer PTL1, and the second patterned layer PTL2. In an embodiment, the second gas used to remove the first patterned layer PTL1 can be substantially the same as the second gas used to etch the hard mask layer HML.

[0115] Figure 14 This is a view illustrating an embodiment of the process for separating the substrate BS from the cell mask CMK according to the present invention.

[0116] refer to Figure 14 The formation of the cell mask CMK and the mesh frame MSF may further include: separating the substrate BS from the cell mask CMK.

[0117] Mask assembly MKA (reference) Figure 3 This can be achieved by setting the cell mask CMK and the mesh frame MSF, which are separate from the substrate BS, in the mask frame MF (refer to...). Figure 3 The unit mask CMK and the mesh frame MSF can be set on the mask frame MF while tension is applied to the unit mask CMK and the mesh frame MSF.

[0118] Although embodiments of the present invention have been described, it should be understood that the present invention is not limited to these embodiments, but rather that various changes and modifications can be made by those skilled in the art within the spirit and scope of the present invention.

[0119] Therefore, the subject matter disclosed herein should not be limited to any single embodiment described herein, and the scope of the invention should be determined in accordance with the appended claims.

Claims

1. A method of manufacturing a mask assembly, comprising: forming a unit mask including a plurality of mask patterns and a grid frame including a plurality of conductive patterns arranged to respectively correspond to the plurality of mask patterns; and arranging the unit mask and the grid frame on a mask frame, the forming the unit mask and the grid frame includes: forming a polymer layer on a base substrate; forming a conductive layer on the polymer layer; forming a hard mask layer on the conductive layer; etching the hard mask layer and the conductive layer to form a mask pattern layer including etch patterns; and etching the polymer layer using the mask pattern layer to form the unit mask and the grid frame, wherein the mask pattern layer includes: a first pattern layer formed by etching the hard mask layer; and a second pattern layer formed by etching the conductive layer, wherein the etch patterns include: a plurality of first patterns provided in the first pattern layer; and a plurality of second patterns provided in the second pattern layer, wherein the forming the unit mask and the grid frame further includes etching the plurality of second patterns to form the conductive patterns after forming the unit mask.

2. The method of claim 1, wherein, the polymer layer includes a first polymer material, the hard mask layer includes a second polymer material, and the second polymer material is different from the first polymer material, wherein the forming the unit mask and the grid frame further includes: partially removing the mask pattern layer for forming the grid frame; and separating the base substrate from the unit mask, wherein the etching the polymer layer is performed using a first gas that selectively etches the polymer layer among the first pattern layer, the second pattern layer, and the polymer layer.

3. The method of claim 2, wherein, the partially removing the mask pattern layer includes: removing the first pattern layer from the mask pattern layer using a second gas that selectively etches the first pattern layer among the first pattern layer and the second pattern layer, wherein the second gas selectively etches the first pattern layer among the unit mask, the first pattern layer, and the second pattern layer.

4. The method of claim 3, wherein, the forming the unit mask and the grid frame further includes: applying a photoresist on the hard mask layer; and patterning the photoresist to form an etch mask, wherein the forming the mask pattern layer includes: etching the hard mask layer using the etch mask to form the first pattern layer including the plurality of first patterns; and etching the conductive layer using the first pattern layer to form the second pattern layer including the plurality of second patterns, wherein the forming the unit mask and the grid frame further includes removing the etch mask after forming the first pattern layer, wherein the etching the conductive layer is performed using an etchant that selectively etches the conductive layer among the first pattern layer, the conductive layer, and the polymer layer.

5. The method of claim 4, wherein, the etching the hard mask layer includes etching the hard mask layer using a gas, wherein the gas selectively etches the hard mask layer among the hard mask layer and the conductive layer.

6. The method of claim 4, wherein, The etching the plurality of second patterns includes etching the plurality of second patterns included in the second pattern layer using an etchant that selectively etches the second pattern layer among the first pattern layer, the second pattern layer, and the unit mask. 7.A mask assembly comprising: a mask frame including an outer frame through which a unit opening is defined; a unit mask disposed on the mask frame and including a plurality of mask patterns corresponding to the unit opening and including a polymer material; and a mesh frame disposed between the mask frame and the unit mask and including a plurality of conductive patterns respectively corresponding to the plurality of mask patterns, wherein a width of each mask pattern of the plurality of mask patterns continuously decreases as a distance from a corresponding conductive pattern among the plurality of conductive patterns decreases, wherein each conductive pattern of the plurality of conductive patterns includes: a first surface in contact with a corresponding mask pattern among the plurality of mask patterns; and a second surface opposite to the first surface, the first surface having a width equal to or less than the width of each mask pattern of the plurality of mask patterns, and the second surface having a width smaller than the width of the first surface.

8. The mask assembly of claim 7, wherein, Each conductive pattern of the plurality of conductive patterns further includes a side surface portion connecting the first surface and the second surface, and the side surface portion has a curved surface shape.

9. The mask assembly according to claim 7 or 8, wherein, The mesh frame includes a metal material or a transparent conductive oxide, and the unit mask includes a polyimide.

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