Mask assembly

Abstract

A mask assembly is provided, the mask assembly comprising: a frame having an opening defined therein; a support portion on the frame and overlapping the opening; and a mask on the support portion and covering at least a portion of the opening. The support portion may include: a central layer; a first outer layer on the first surface of the center layer; and a second outer layer on a second surface of the central layer, the second surface being opposite the first surface.

Description

[0001] This application is a divisional application of application No. 202010079540.9 entitled “Mask Assembly”, filed on February 4, 2020. Technical Field

[0002] An aspect of the embodiments of this disclosure relates to a mask assembly and a method of manufacturing the mask assembly. Background Art

[0003] The display device may include a plurality of pixels. Each of the plurality of pixels may include an emission layer (or light-emitting layer) disposed between opposing electrodes. The emission layer may be formed by at least one of a variety of methods. For example, the emission layer may be formed by a deposition method using a mask. However, in the process of forming the emission layer using a mask, the shape of the support portion supporting the mask may be deformed, resulting in reduced deposition reliability of the emission layer. Summary of the Invention

[0004] According to one aspect of the embodiments of this disclosure, a mask assembly capable of improving deposition reliability is provided. According to another aspect of the embodiments of this disclosure, a mask assembly capable of reducing shape deformation due to temperature is provided.

[0005] According to another aspect of the embodiments of this disclosure, a method for manufacturing a mask assembly capable of improving deposition reliability is provided.

[0006] According to one or more embodiments of the inventive concept, a mask assembly may include: a frame defining an opening; a support portion located on the frame and overlapping the opening; and a mask located on the support portion and covering at least a portion of the opening. The support portion may include: a central layer; a first outer layer located on a first surface of the central layer; and a second outer layer located on a second surface of the central layer, the second surface being opposite to the first surface.

[0007] In one embodiment, the first surface may be in direct contact with the first outer layer, and the second surface may be in direct contact with the second outer layer.

[0008] In one embodiment, the central layer may be bonded to a first outer metal layer, and the central layer may be bonded to a second outer metal layer.

[0009] In an embodiment, the central layer may include a material different from the first outer layer and the second outer layer, and the first outer layer and the second outer layer may include the same material.

[0010] In an embodiment, the coefficient of thermal expansion of the central layer may be different from that of the first outer layer.

[0011] In an embodiment, the magnetic force of the central layer may be greater than the magnetic force of each of the first and second outer layers.

[0012] In an embodiment, the central layer may include Invar alloy, and each of the first and second outer layers may include stainless steel.

[0013] In an embodiment, the support portion may be configured as multiple support portions, and the multiple support portions may extend in a first direction and may be arranged in a second direction intersecting the first direction.

[0014] In an embodiment, the support portion may be configured as a plurality of support portions, some of which may extend in a first direction and may be arranged in a second direction intersecting the first direction, and other of which may extend in the second direction and may be arranged in the first direction.

[0015] In an embodiment, the mask may be configured as a plurality of masks, which may extend in a first direction and be arranged in a second direction, and a plurality of opening patterns may be defined in each mask.

[0016] In an embodiment, each of the frame and the mask may include Invar alloy.

[0017] In one embodiment, the support portion may have a symmetrical structure relative to the central layer.

[0018] In this embodiment, the first outer layer and the second outer layer may have the same thickness.

[0019] In this embodiment, the first outer layer and the second outer layer may have the same coefficient of thermal expansion.

[0020] According to one or more embodiments of the inventive concept, a mask assembly may include: a frame defining an opening; a support portion located on the frame and stacked with the opening; and a mask located on the support portion and covering at least a portion of the opening. The support portion may include an odd number of substrate layers, and the substrate layers may have a coefficient of thermal expansion that is symmetrical with respect to the central layer of the substrate layers.

[0021] In one embodiment, the support portion may include a first outer layer in the substrate layer located between the central layer and the frame, and a second outer layer in the substrate layer located between the central layer and the mask. The magnetic force of each of the first and second outer layers may be less than the magnetic force of the central layer.

[0022] In an embodiment, the central layer may include Invar alloy, and each of the first and second outer layers may include stainless steel.

[0023] According to one or more embodiments of the inventive concept, a method of manufacturing a mask assembly may include: providing a frame in which an opening is defined; forming a support portion disposed on the frame and overlapping the opening; and providing a mask disposed on the support portion and covering at least a portion of the opening. The step of forming the support portion may include: preparing 2n+1 base members, where n is a natural number of 1 or greater; and joining the base members together by applying pressure to the base members.

[0024] In an embodiment, the step of forming the support portion may further include: scraping the surface of each base member facing another base member.

[0025] In the embodiments, the step of joining the substrate components can be repeated multiple times. Attached Figure Description

[0026] The accompanying drawings are included to provide a further understanding of the inventive concept and are incorporated in and form part of this specification. The drawings illustrate some exemplary embodiments of the inventive concept and, together with the description, serve to explain the principles of the inventive concept. In the drawings:

[0027] Figure 1 This is an exploded perspective view showing a mask assembly according to an embodiment of the inventive concept;

[0028] Figure 2 This is a cross-sectional view showing a deposition apparatus according to an embodiment of the inventive concept;

[0029] Figure 3 This is a cross-sectional view showing the base and mask according to an embodiment of the inventive concept;

[0030] Figure 4 This is a plan view showing the support portion according to an embodiment of the inventive concept;

[0031] Figure 5 This is a cross-sectional view showing a support portion according to an embodiment of the inventive concept;

[0032] Figure 6 This is a cross-sectional view showing a support portion according to an embodiment of the inventive concept;

[0033] Figure 7 This is a cross-sectional view showing a support portion according to an embodiment of the inventive concept;

[0034] Figure 8A This is an exploded perspective view showing a mask assembly according to an embodiment of the inventive concept;

[0035] Figure 8B This is an exploded perspective view showing a mask assembly according to an embodiment of the inventive concept;

[0036] Figure 9 This is a flowchart illustrating a method for manufacturing a mask assembly according to an embodiment of the inventive concept;

[0037] Figure 10 This is a flowchart illustrating a method for manufacturing a support portion according to an embodiment of the inventive concept; and

[0038] 11A to 11D This is a cross-sectional view schematically illustrating some processes of a method for manufacturing a support portion according to an embodiment of the inventive concept. Detailed Implementation

[0039] The inventive concept will be described more fully herein with reference to the accompanying drawings, in which various exemplary embodiments are illustrated. However, the inventive concept can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. The same reference numerals throughout denote the same elements.

[0040] It will be understood that when an element such as a layer, region, or substrate is referred to as being "on" another element, the element may be directly on said other element, or one or more intermediate elements may be present. Conversely, the term "directly" implies the absence of intermediate elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0041] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms “a” and “the” are intended to include the plural forms containing “at least one”, unless the content clearly indicates otherwise. “Or” means “and / or”. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. It will also be understood that when the terms “comprising,” “including,” and / or variations thereof are used in this specification, they indicate the presence of the stated features, regions, integrals, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, regions, integrals, steps, operations, elements, components, and / or groups thereof.

[0042] For ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” etc., are used herein to describe the relationship between one element or feature as shown in the accompanying drawings and another (other) element or feature. It will be understood that, in addition to the orientations depicted in the drawings, the spatial relative terms are intended to encompass different orientations of the device in use or operation. For example, if the device in the accompanying drawings is flipped, an element described as “below” or “under” other elements or features would subsequently be positioned “above” other elements or features. Thus, the exemplary term “below” can encompass both the orientations above and below. The device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used herein shall be interpreted accordingly.

[0043] It will be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or part from another. Therefore, the first element, component, region, layer, or part discussed below may be referred to as the second element, component, region, layer, or part without departing from the teaching herein.

[0044] Taking into account the measurements discussed and the errors associated with the measurement of a particular quantity (e.g., limitations of the measurement system), as used herein, “about” or “approximately” includes the stated values ​​and means within an acceptable range of deviation from the particular values ​​as determined by one of ordinary skill in the art.

[0045] The exemplary embodiments can be described herein with reference to cross-sectional views and / or plan views, which may serve as idealized exemplary diagrams. In the drawings, the thickness of layers and regions may be exaggerated for clarity. Therefore, variations in shape as illustrated by, for example, manufacturing techniques and / or tolerances will be expected. Thus, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing processes. For example, etched regions shown as rectangles would typically have rounded or curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shape of the regions of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0046] 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 the exemplary embodiments of the inventive concept pertain. It will also be understood that terms (such as those defined in a general dictionary) shall be interpreted as having a meaning consistent with their meaning in the context of the relevant field and shall not be interpreted in an idealized or overly formalized sense, unless expressly defined herein.

[0047] Here, some exemplary embodiments of the inventive concept will be described in more detail with reference to the accompanying drawings.

[0048] Figure 1 This is an exploded perspective view showing a mask assembly according to an embodiment of the inventive concept.

[0049] Reference Figure 1 The mask assembly MA can be used in the process of depositing deposited materials. In embodiments of the inventive concept, the mask assembly MA may include a frame FR, a support portion SP, and a mask MK.

[0050] When viewed in a plan view, the frame FR can have a ring or loop shape. In other words, an opening OP can be provided in a region of the frame FR (such as the region including the center). The opening OP can be a hole penetrating the frame FR from the top surface to the bottom surface of the frame FR.

[0051] exist Figure 1 In the diagram, a rectangular ring shape is shown as an example of the shape of the frame FR. However, the shape of the frame FR is not limited to this. In some embodiments, the frame FR may have at least one of a variety of other shapes, such as a circular ring shape and a polygonal ring shape.

[0052] The support portion SP can be mounted on the frame FR. The support portion SP can overlap at least a portion of the opening OP of the frame FR. The support portion SP can divide the opening OP into multiple areas.

[0053] In an embodiment, the support portion SP can be configured as multiple, and the support portion SP will be described herein.

[0054] The support portion SP may include a first support portion SP1 and a second support portion SP2. Each of the first support portions SP1 may extend in a first direction DR1. The first support portions SP1 may be spaced apart from each other and arranged in a second direction DR2 intersecting the first direction DR1. Each of the second support portions SP2 may extend in the second direction DR2. The second support portions SP2 may be spaced apart from each other and arranged in the first direction DR1. The distance between the first support portions SP1 and the distance between the second support portions SP2 may be adjusted according to the size and shape of the area in which the deposited material will be deposited.

[0055] exist Figure 1 The diagram illustrates, by way of example, two first support portions SP1 and two second support portions SP2. However, the number of each of the first support portions SP1 and the second support portions SP2 is not limited thereto. In some embodiments, the number of each of the first support portions SP1 and the second support portions SP2 may be one, three, or more.

[0056] In an embodiment, such as Figure 1 As shown, the first width of each of the first support portions SP1 in the second direction DR2 is equal to the second width of each of the second support portions SP2 in the first direction DR1. However, embodiments of the inventive concept are not limited thereto. In some embodiments, the first width may be different from the second width. For example, in an embodiment, the first width of each of the first support portions SP1 having a longer length may be greater than the second width.

[0057] The first support portion SP1 and the second support portion SP2 can be coupled to the frame FR. For example, the first support portion SP1 and the second support portion SP2 can be coupled to the frame FR by welding. However, embodiments of the inventive concept are not limited thereto. In another embodiment, the first support portion SP1 and the second support portion SP2 can be coupled to the frame FR by a coupling member (not shown), and the coupling member may include a material with adhesive properties. In yet another embodiment, a groove (not shown) can be provided at the top surface of the frame FR. The groove can be recessed from the top surface of the frame FR, and the first support portion SP1 and the second support portion SP2 can be inserted into the groove. In other words, the first support portion SP1 and the second support portion SP2 can engage with the frame FR.

[0058] The mask MK can be disposed on the support portion SP. In embodiments, multiple masks MK can be disposed, and the masks MK will be described herein.

[0059] The mask MK can be supported by support portions SP. In an embodiment, a first support portion SP1 can support the boundary between masks MK, and a second support portion SP2 can support a portion of each of the masks MK.

[0060] In an embodiment, each of the masks MK may extend in a first direction DR1, and the masks MK may be arranged in a second direction DR2.

[0061] Multiple opening patterns (OPPs) can be defined in each of the mask MK. When viewed in a plan view, the multiple opening patterns (OPPs) may not be superimposed on the support portion (SP) and may be superimposed on the opening (OP). The opening pattern (OPP) may be a through-hole penetrating the mask MK from the top surface of the mask MK to the bottom surface of the mask MK.

[0062] The mask MK can be bonded to the support portion SP. For example, the mask MK can be bonded to the corresponding support portion SP by welding. However, embodiments of the inventive concept are not limited thereto. In another embodiment, the mask MK can be bonded to the support portion SP by a bonding member (e.g., adhesive).

[0063] Figure 2 This is a cross-sectional view showing a deposition apparatus according to an embodiment of the inventive concept.

[0064] Reference Figure 2 The deposition apparatus (DPD) may include a chamber (CHB), a deposition source (S), a stage (STG), a moving plate (PP), and a mask assembly (MA).

[0065] The chamber CHB can provide a closed or sealed space. A deposition source S, a stage STG, a moving plate PP, and a mask assembly MA can be housed within the chamber CHB. The chamber CHB can have at least one door GT. The chamber CHB can be opened / closed via the door GT. The target substrate SUB can enter and exit the chamber CHB through the door GT.

[0066] The deposition source S may include a deposition material. The deposition material may include a material capable of sublimation or evaporation (e.g., at least one of inorganic, metallic, and organic materials). In an embodiment, the deposition source S may include an organic material for forming an organic light-emitting element (not shown).

[0067] The STG platform can be positioned on top of the deposition source S. The mask assembly MA can be placed on the STG platform. The mask assembly MA can face the deposition source S. The STG platform can be stacked with and support the frame FR of the mask assembly MA. The STG platform can also be separate from the opening OP of the frame FR. In other words, the STG platform can be positioned outside the path of the deposition material supplied from the deposition source S to the target substrate SUB.

[0068] The target substrate SUB can be set on the mask assembly MA. Deposited material can be deposited onto the target substrate SUB through an opening pattern OPP.

[0069] The movable plate PP aligns the target substrate SUB on the mask assembly MA. For example, the movable plate PP can generate electrostatic or magnetic forces to move the target substrate SUB. The movable plate PP can be movable vertically or horizontally.

[0070] In another embodiment, a movable plate PP can fix the target substrate SUB onto the mask assembly MA. Since the target substrate SUB is fixed onto the mask assembly MA by the movable plate PP, the accuracy of the deposition process can be improved.

[0071] Figure 3 This is an enlarged cross-sectional view showing portions of the target substrate and mask according to an embodiment of the inventive concept.

[0072] Reference Figure 3 In this embodiment, the mask MK may be in contact with the target substrate SUB. Deposition material may be deposited on the target substrate SUB exposed through the opening pattern OPP of the mask MK.

[0073] For example, in an embodiment, the target substrate SUB may include a substrate layer BS, a first insulating layer 10, a second insulating layer 20, a third insulating layer 30, a fourth insulating layer 40, a fifth insulating layer 50 and a sixth insulating layer 60, a transistor TR and a first electrode E1.

[0074] In the embodiments, the substrate layer BS may be a silicon substrate, a plastic substrate, a glass substrate, an insulating film, or a stacked structure including multiple insulating layers.

[0075] The first insulating layer 10 may be disposed on the substrate layer BS. The first insulating layer 10 may include a barrier layer 11 and a buffer layer 12.

[0076] Barrier layer 11 may include inorganic materials. Barrier layer 11 can prevent or substantially prevent oxygen or moisture from penetrating into the pixel through the substrate layer BS. Buffer layer 12 may include inorganic materials. Buffer layer 12 can provide the pixel with a surface energy lower than that of the substrate layer BS, allowing the pixel to be stably formed on the substrate layer BS. Figure 3 In the diagram, each of the barrier layer 11 and the buffer layer 12 is shown as a single layer. However, embodiments of the inventive concept are not limited thereto. In another embodiment, each of the barrier layer 11 and the buffer layer 12 may be multiple, and the barrier layer 11 and the buffer layer 12 may be stacked alternately. In other embodiments, at least one of the barrier layer 11 and the buffer layer 12 may be multiple or may be omitted.

[0077] Each pixel can include pixel circuitry and a light-emitting element. Pixel circuitry can include a transistor (TR) and a capacitor. Figure 3 In the image, a transistor TR is shown as an example.

[0078] A transistor TR can be disposed on the first insulating layer 10. The transistor TR may include a semiconductor pattern SM, a control electrode CE, an input electrode IE, and an output electrode OE. The semiconductor pattern SM can be disposed on the first insulating layer 10. The semiconductor pattern SM may include a semiconductor material. The control electrode CE may be separated from the semiconductor pattern SM, and a second insulating layer 20 is disposed between the control electrode CE and the semiconductor pattern SM.

[0079] The input electrode IE and output electrode OE can be separated from the control electrode CE. The third insulating layer 30 and the fourth insulating layer 40 are placed between the input electrode IE and output electrode OE and the control electrode CE. The input electrode IE and output electrode OE can penetrate the second insulating layer 20, the third insulating layer 30 and the fourth insulating layer 40 to connect to one side and the other side of the semiconductor pattern SM, respectively.

[0080] The upper electrode UE can be disposed between the third insulating layer 30 and the fourth insulating layer 40. The upper electrode UE can be connected to an electrode of the capacitor. The other electrode of the capacitor can be electrically connected to the control electrode CE.

[0081] The fifth insulating layer 50 can be disposed on the fourth insulating layer 40 to cover the input electrode IE and the output electrode OE.

[0082] The first electrode E1 can be disposed on the fifth insulating layer 50. The first electrode E1 can penetrate the fifth insulating layer 50 to be electrically connected to the transistor TR.

[0083] A sixth insulating layer 60 may be disposed on the fifth insulating layer 50. An opening may be defined in the sixth insulating layer 60, and the opening may expose at least a portion of the first electrode E1. The sixth insulating layer 60 may be a pixel defining layer.

[0084] The mask MK may contact the sixth insulating layer 60. When viewed in plan view, the opening pattern OPP of the mask MK may overlap with the openings of the sixth insulating layer 60. Deposited material may pass through the opening pattern OPP of the mask MK and then be deposited on the first electrode E1. For example, an emitter layer EL may be formed on the first electrode E1. The deposited material may be the material used to form the emitter layer EL. In other words, the emitter layer EL may be a deposited material deposited on the target substrate SUB.

[0085] The emitting layer (EL) may include luminescent materials. For example, the emitting layer EL may include at least one of materials selected for emitting red, green, and blue light. The emitting layer EL may include fluorescent or phosphorescent materials. The emitting layer EL may include organic or inorganic luminescent materials.

[0086] Figure 4 This is a plan view showing the support portion according to an embodiment of the inventive concept.

[0087] Reference Figure 4 Each of the first support portions SP1 may have a first length LT1 in the first direction DR1, and each of the second support portions SP2 may have a second length LT2 in the second direction DR2.

[0088] The first length LT1 and the second length LT2 can be determined according to the chamber CHB (see...). Figure 2 The internal temperature of the support portion SP1 changes. If each of the first length LT1 and the second length LT2 increases by a certain length (e.g., a predetermined length) or more, each of the first support portion SP1 and the second support portion SP2 will sag up and down in the direction of gravity. This will cause a deterioration in the reliability of the deposition.

[0089] Refer again Figure 1 The appropriate range of the coefficient of thermal expansion can be changed or selected based on the resolution of the opening pattern OPP of the mask MK, the size of the frame FR, the size or weight of the mask MK, the first length LT1 and / or the second length LT2.

[0090] According to embodiments of the inventive concept, a first support portion SP1 and a second support portion SP2 can be provided having a coefficient of thermal expansion within a certain range (e.g., a predetermined range). Therefore, it is possible to prevent or substantially prevent degradation of deposition reliability due to deformation of the shapes of the first support portion SP1 and the second support portion SP2. The coefficient of thermal expansion can be measured using a thermomechanical analyzer (TMA). The coefficient of thermal expansion can be measured based on a change in the length of the sample as it changes from room temperature to a specific temperature.

[0091] Figure 5 This is a cross-sectional view showing a support portion according to an embodiment of the inventive concept. Figure 5 It can be along Figure 4 A sectional view taken from line I-I'.

[0092] Reference Figure 5 The thickness TkS of the first support part SP1 can be greater than that of the frame FR (see...). Figure 2 The frame thickness TkF (see) Figure 2 Much smaller. For example, in the embodiment, the frame thickness TkF (see...) Figure 2The thickness of the support portion can range from a few centimeters to tens of centimeters, and the thickness TkS of the support portion can range from a few micrometers to hundreds of micrometers. For example, the thickness TkS of the support portion can range from 10 micrometers to 200 micrometers. The first support portion SP1 is more prone to shape deformation due to thermal expansion than the frame FR. According to embodiments of the inventive concept, the first support portion SP1 can be controlled to have a coefficient of thermal expansion within a certain range (e.g., a predetermined range), thus minimizing or reducing the shape deformation of the first support portion SP1. In an embodiment, the second support portion SP2 (see...) Figure 2 The second support portion SP2 can have a structure that is substantially the same as that of the first support portion SP1, therefore, further description of the second support portion SP2 will be omitted.

[0093] According to an embodiment of the inventive concept, the first support portion SP1 can be a clad structure. The first support portion SP1 may include an odd number of base layers, such as a central layer CL, a first outer layer OL1, and a second outer layer OL2.

[0094] The central layer CL may be a layer disposed at the center of the first support portion SP1. The central layer CL may include a first surface SF1 and a second surface SF2. The first surface SF1 and the second surface SF2 may be opposite to each other.

[0095] The first outer layer OL1 can be disposed on the first surface SF1, and the second outer layer OL2 can be disposed on the second surface SF2. In an embodiment, the first surface SF1 can be in direct contact with the first outer layer OL1, and the second surface SF2 can be in direct contact with the second outer layer OL2. In other words, other components are not disposed between the central layer CL and the first outer layer OL1, or between the central layer CL and the second outer layer OL2. Therefore, the first support portion SP1 can be a composite material integrally formed by combining the surfaces of the first outer layer OL1, the central layer CL, and the second outer layer OL2.

[0096] The central layer CL may include a material different from the materials of the first outer layer OL1 and the second outer layer OL2. In an embodiment, the first outer layer OL1 and the second outer layer OL2 may include the same material. For example, the first outer layer OL1 and the second outer layer OL2 may have the same coefficient of thermal expansion, and the central layer CL may include a material having a different coefficient of thermal expansion than the first outer layer OL1 and the second outer layer OL2.

[0097] Since the central layer CL, the first outer layer OL1, and the second outer layer OL2 constitute the first support portion SP1, the coefficient of thermal expansion of the entire first support portion SP1 can be easily adjusted. For example, when the central layer CL comprises a specific material (e.g., a predetermined material), the coefficient of thermal expansion of the entire first support portion SP1 can be adjusted by changing the materials of the first outer layer OL1 and the second outer layer OL2. On the other hand, when the first outer layer OL1 and the second outer layer OL2 comprise a specific material (e.g., a predetermined material), the coefficient of thermal expansion of the entire first support portion SP1 can be adjusted by changing the material of the central layer CL.

[0098] In an embodiment, the first thickness Tk1 of the central layer CL, the second thickness Tk2 of the first outer layer OL1, and the third thickness Tk3 of the second outer layer OL2 can be equal to each other (equal or substantially equal). In an embodiment, the coefficient of thermal expansion of the first support portion SP1 can be adjusted by adjusting each of the first thickness Tk1, the second thickness Tk2, and the third thickness Tk3.

[0099] For example, the first thickness Tk1 can have a thickness of 10% to 90% of the supporting thickness TkS. Each of the second thickness Tk2 and the third thickness Tk3 can be based on a ratio of the first thickness Tk1 to the supporting thickness TkS. For example, each of the second thickness Tk2 and the third thickness Tk3 can have a thickness of 5% to 45% of the supporting thickness TkS.

[0100] In the embodiments, the second thickness Tk2 and the third thickness Tk3 can be equal to each other (equal or substantially equal). For example, even if the first outer layer OL1 and the second outer layer OL2 can comprise the same material, if the second thickness Tk2 and the third thickness Tk3 are different, the amount by which the length of the first outer layer OL1 changes with temperature will be different from the amount by which the length of the second outer layer OL2 changes with temperature. In this case, the first support portion SP1 will warp in one direction. However, when the second thickness Tk2 is substantially equal to the third thickness Tk3, the amount by which the length of the first outer layer OL1 changes with temperature will be substantially equal to the amount by which the length of the second outer layer OL2 changes with temperature. Therefore, it is possible to prevent or substantially prevent the first support portion SP1 from warping in a particular direction.

[0101] In an embodiment, the first support portion SP1 may have a structure symmetrical with respect to the central layer CL. For example, the second thickness Tk2 of the first outer layer OL1 and the third thickness Tk3 of the second outer layer OL2 may be equal to (or substantially equal to) each other with respect to the central layer CL. Furthermore, the coefficients of thermal expansion of the first outer layer OL1 and the second outer layer OL2 may be equal to each other with respect to the central layer CL.

[0102] In this embodiment, the magnetic force of the central layer CL can be greater than that of the first outer layer OL1 and the second outer layer OL2. In this embodiment, the magnetic force of each of the first outer layer OL1 and the second outer layer OL2 can be close to zero. For example, the first outer layer OL1 and the second outer layer OL2 can comprise non-magnetic materials. Since the outer layer of the first support portion SP1 can be formed of a non-magnetic material, the influence of electrostatic or magnetic forces generated during the process on the first support portion SP1 can be minimized or reduced. The magnetic force can be measured using a magnetic properties measurement system (MPMS) or a physical properties measurement system (PPMS). The magnetic force can be estimated using BH curves or MH curves.

[0103] In one embodiment, the central layer CL may comprise Invar alloy, and each of the first outer layer OL1 and the second outer layer OL2 may comprise stainless steel. The stainless steel may be SUS301, SUS304, or SUS316. However, the materials of the central layer CL and the first and second outer layers OL1 and OL2 are not limited to the examples above. In another embodiment, the central layer CL may comprise stainless steel, and each of the first and second outer layers OL1 and OL2 may comprise Invar alloy.

[0104] The central layer CL and the first outer layer OL1 can be metal-bonded to each other, and the central layer CL and the second outer layer OL2 can be metal-bonded to each other. Metal bonding can mean that an alloy is formed at the bonding interface between the central layer CL and the first outer layer OL1 and at the bonding interface between the central layer CL and the second outer layer OL2.

[0105] Figure 6 This is a cross-sectional view showing a support portion according to an embodiment of the inventive concept.

[0106] Reference Figure 6 A cross-section of the first support portion SP1-1 is shown as an example. In an embodiment, the first support portion SP1-1 may be a covering structure. The first support portion SP1-1 may include a central layer CL-1, a first outer layer OL1-1, and a second outer layer OL2-1.

[0107] The first support part SP1-1 can have a structure symmetrical with respect to the central layer CL-1 and a coefficient of thermal expansion symmetrical with respect to the central layer CL-1.

[0108] The first thickness Tk1-1 of the central layer CL-1 can be different from the second thickness Tk2-1 of the first outer layer OL1-1 and the third thickness Tk3-1 of the second outer layer OL2-1. The second thickness Tk2-1 can be equal to (or substantially equal to) the third thickness Tk3-1.

[0109] In an embodiment, such as Figure 6As shown, the first thickness Tk1-1 is larger than the second thickness Tk2-1 and the third thickness Tk3-1. However, embodiments of the inventive concept are not limited thereto. In another embodiment, the second thickness Tk2-1 and the third thickness Tk3-1 may be larger than the first thickness Tk1-1.

[0110] Figure 7 This is a cross-sectional view showing a support portion according to an embodiment of the inventive concept.

[0111] Reference Figure 7 A cross-section of the first support portion SP1-2 is shown as an example.

[0112] In this embodiment, the first support portion SP1-2 may be a covering structure. The first support portion SP1-2 may include a central layer CL-2, a first outer layer OL1-2, a second outer layer OL2-2, a third outer layer OL3-2, and a fourth outer layer OL4-2. The first support portion SP1-2 may have a structure symmetrical with respect to the central layer CL-2 and a coefficient of thermal expansion symmetrical with respect to the central layer CL-2.

[0113] In an embodiment, the first support portion may include 2n+1 base layers, where n is a natural number of 1 or greater. For example, refer to... Figure 5 and Figure 6 Each of the first support portions SP1 and SP1-1 described includes three matrix layers. Figure 7 As an example, the first support portion SP1-2, which includes five base layers, is shown in the image.

[0114] pass Figures 5 to 7 The first support portion is described. However, similar to the first support portion, Figure 4 The second support portion SP2 shown may also include 2n+1 base layers, where n is a natural number of 1 or greater. Furthermore, the second support portion SP2 may also be an encapsulation structure.

[0115] Figure 8A This is an exploded perspective view showing a mask assembly according to an embodiment of the inventive concept.

[0116] Reference Figure 8A The mask assembly MA-1 may include a frame FR, support portions SP-1, and a mask MK. In an embodiment, each of the support portions SP-1 may be an overlay structure and may include 2n+1 base layers, where n is a natural number of 1 or greater.

[0117] The mask MK can extend in the first direction DR1 and can be arranged in the second direction DR2. The support part SP-1 can extend in the first direction DR1 and can be arranged in the second direction DR2.

[0118] One of the support sections SP-1 can be stacked with two adjacent masks MK. In other words, one support section can support two masks.

[0119] Figure 8B This is an exploded perspective view showing a mask assembly according to an embodiment of the inventive concept.

[0120] Reference Figure 8B The mask assembly MA-2 may include a frame FR, support portions SP-2, and a mask MK. In an embodiment, each of the support portions SP-2 may be an overlay structure and may include 2n+1 base layers, where n is a natural number of 1 or greater.

[0121] The mask MK can extend in a first direction DR1 and can be arranged in a second direction DR2. The support portion SP-2 can extend in the second direction DR2 and can be arranged in the first direction DR1. The extension direction of each of the support portions SP-2 can intersect the extension direction of each of the masks MK. In an embodiment, each of the support portions SP-2 can support all masks MK.

[0122] When viewed in a plan view, the support portion SP-2 may not overlap with the effective area of ​​the mask MK. The effective area represents the region through which the deposited material passes. Figure 8B In this context, the area with the opening pattern OPP can be defined as the effective area. Therefore, when viewed in a plan view, the support portion SP-2 does not need to overlap with the opening pattern OPP.

[0123] Figure 9 This is a flowchart illustrating a method for manufacturing a mask assembly according to an embodiment of the inventive concept.

[0124] Reference Figure 1 and Figure 9 A frame FR (S100) can be formed or provided. An opening OP can be defined within the frame FR. In an embodiment, the frame FR may include Invar alloy. In an embodiment, each of the frame FR and the mask MK may include Invar alloy.

[0125] A support portion SP can be formed (S200). The support portion SP can be disposed on the frame FR. The support portion SP can be disposed on the frame FR to overlap with the opening OP. In an embodiment, the support portion SP may include at least two or more materials.

[0126] A mask MK (S300) can be formed or provided. An opening pattern OPP can be defined within the mask MK. The mask MK can be disposed on the support portion SP. When viewed in a plan view, the opening pattern OPP may not be superimposed on the support portion SP, but may be superimposed on the opening OP.

[0127] The mask assembly MA (S400) can be formed by combining the frame FR, the support part SP, and the mask MK together.

[0128] Figure 10 This is a flowchart illustrating a method for manufacturing a support portion according to an embodiment of the inventive concept (corresponding to...). Figure 9 (S200 in the middle). 11A to 11D This is a cross-sectional view schematically illustrating some processes of a method for manufacturing a support portion according to an embodiment of the inventive concept.

[0129] Reference Figure 10 and Figure 11A An odd number of base components BM1, BM2, and BM3 (S210) can be prepared. Figure 11A The diagram illustrates three base components BM1, BM2, and BM3 as an example. These three base components BM1, BM2, and BM3 may include a first base component BM1, a second base component BM2, and a third base component BM3.

[0130] The first base component BM1 may include a first surface SF1a and a second surface SF1b, the second base component BM2 may include a first surface SF2a and a second surface SF2b, and the third base component BM3 may include a first surface SF3a and a second surface SF3b. ​​The second base component BM2, the first base component BM1, and the third base component BM3 may be arranged sequentially in one direction. The first surface SF1a may face the second surface SF2b, and the second surface SF1b may face the first surface SF3a.

[0131] The first substrate component BM1 may have a first thickness Tk-B1, the second substrate component BM2 may have a second thickness Tk-B2, and the third substrate component BM3 may have a third thickness Tk-B3. In an embodiment, the second thickness Tk-B2 and the third thickness Tk-B3 may be equal to each other. The ratio of each of the second thickness Tk-B2 and the third thickness Tk-B3 to the first thickness Tk-B1 can be adjusted differently. For example, this ratio can be adjusted according to a set range of the coefficient of thermal expansion, such that the coefficient of thermal expansion is within the set range.

[0132] Reference Figure 10 and Figure 11BAt least a portion of the surfaces of each of the three base members BM1, BM2, and BM3 facing the other base members can be scraped (S220). For example, at least a portion of the first surface SF1a, the second surface SF1b, the second surface SF2b, and the first surface SF3a can be scraped. For example, the first surface SF1a can be scraped using a scraping member SKM. A rough surface PTT can be formed in the area of ​​the first surface SF1a through which the scraping member SKM passes. The three base members BM1, BM2, and BM3 can be easily joined or bonded to each other using the rough surface PTT.

[0133] In some embodiments, the scraping member SKM can be used to scrape all surfaces of the first surface SF1a, the second surface SF1b, the second surface SF2b, and the first surface SF3a, or the scraping member SKM can be used to scrape one or some of the surfaces of the first surface SF1a, the second surface SF1b, the second surface SF2b, and the first surface SF3a. In another embodiment, the process of scraping the first surface SF1a, the second surface SF1b, the second surface SF2b, and the first surface SF3a using the scraping member SKM can be omitted.

[0134] Reference Figure 10 and Figure 11C In this embodiment, three base components BM1, BM2, and BM3 may be disposed between the joining rollers BR. The joining rollers BR may apply pressure to the three base components BM1, BM2, and BM3 to engage the three base components BM1, BM2, and BM3 with each other (S230).

[0135] In this embodiment, the process of joining substrate components BM1, BM2, and BM3 using the joining roller BR can be repeated multiple times. (Refer to...) Figure 11D This can form a first support portion SP1 with a support portion thickness TkS.

[0136] In this embodiment, heat can be applied to the bonding roll BR. For example, the bonding roll BR can apply heat and pressure to the base components BM1, BM2, and BM3. In this embodiment, the environment in which the base components BM1, BM2, and BM3 are pressed using the bonding roll BR can have a predetermined temperature range. In this case, the base components BM1, BM2, and BM3 can be bonded to each other in an environment with a predetermined temperature range. In other words, the process of applying pressure to the base components BM1, BM2, and BM3 while applying heat can be referred to as a hot rolling process.

[0137] The process of forming the first support portion SP1 using the base components BM1, BM2, and BM3 may also include a cold rolling process. The cold rolling process can be a process in which pressure is applied to the base components BM1, BM2, and BM3 at room temperature.

[0138] In some embodiments, the process of forming the first support portion SP1 may include both cold rolling and hot rolling, or may include only cold rolling or only hot rolling.

[0139] According to embodiments of the inventive concept, the mask assembly may include a support portion supporting the mask. The support portion may include multiple substrate layers. The coefficient of thermal expansion of the support portion can be adjusted by changing or selecting the material and / or thickness of each of the substrate layers. Therefore, the coefficient of thermal expansion of the support portion can be set within a range that minimizes or reduces shape deformation of the support portion. As a result, deposition reliability can be improved.

[0140] While the inventive concept has been described with reference to some exemplary embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the inventive concept. Therefore, it should be understood that the above embodiments are not restrictive but illustrative. Consequently, the scope of the inventive concept will be determined by the broadest permissible interpretation of the claims and their equivalents, and should not be limited or restricted by the foregoing description.

Claims

1. A mask assembly, the mask assembly comprising: A frame, in which an opening is defined; A first support portion is located on the frame, overlaps with the opening, and extends in a first direction; The second support portion is located on the frame, overlaps with the opening, and extends in a second direction intersecting the first direction; as well as A mask, located on the first support portion and the second support portion and covering at least a portion of the opening, Wherein, the first support portion or the second support portion includes: Central layer; A first outer layer, located on the first surface of the central layer; and The second outer layer is located on the second surface of the central layer, and the second surface is opposite to the first surface. The magnetic force of the central layer is greater than that of each of the first and second outer layers. The first length of the first support portion and the second length of the second support portion are different. The first coefficient of thermal expansion of the first support portion and the second coefficient of thermal expansion of the second support portion are different. Wherein, the first support portion or the second support portion has a symmetrical structure relative to the central layer, and The first outer layer and the second outer layer have the same thickness.

2. The mask assembly as claimed in claim 1, wherein, The first surface is in direct contact with the first outer layer, and the second surface is in direct contact with the second outer layer.

3. The mask assembly as claimed in claim 1, wherein, The central layer is bonded to the first outer metal layer, and the central layer is bonded to the second outer metal layer.

4. The mask assembly as claimed in claim 1, wherein, The central layer comprises a different material from the first outer layer and the second outer layer, and the first outer layer and the second outer layer comprise the same material.

5. The mask assembly as claimed in claim 1, wherein, The coefficient of thermal expansion of the central layer is different from that of the first outer layer.

6. The mask assembly as claimed in claim 1, wherein, The central layer comprises Invar alloy, and each of the first and second outer layers comprises stainless steel.

7. The mask assembly as claimed in claim 1, wherein, The mask is configured as a plurality of masks, which extend in the first direction and are arranged in the second direction; and a plurality of opening patterns are defined in each of the plurality of masks.

8. The mask assembly as claimed in claim 1, wherein, Each of the frame and the mask comprises Invar alloy.

9. The mask assembly of claim 1, wherein, The first outer layer and the second outer layer have the same coefficient of thermal expansion.

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