Mask components

Abstract

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

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0014491 filed on February 7, 2019, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Aspects of embodiments of the present disclosure relate 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 emissive layer (or light-emitting layer) disposed between opposing electrodes. The emissive layer may be formed by at least one of various methods. For example, the emissive layer may be formed by a deposition method using a mask. However, in the process of forming the emissive layer using a mask, the shape of the support portion of the support mask may be deformed, resulting in reduced deposition reliability of the emissive layer. Summary of the Invention

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

[0005] According to another aspect of an embodiment of the present disclosure, a method of 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 positioned on the frame and overlapping the opening; and a mask positioned on the support portion and covering at least a portion of the opening. The support portion may include: a core layer; a first outer layer positioned on a first surface of the core layer; and a second outer layer positioned on a second surface of the core layer, the second surface being opposite the first surface.

[0007] In an 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 an embodiment, the center layer may be bonded to the first outer layer of metal, and the center layer may be bonded to the second outer layer of metal.

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

[0010] In an embodiment, the coefficient of thermal expansion of the center layer may be different than the coefficient of thermal expansion of the first outer layer.

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

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

[0013] In an embodiment, the support portion may be provided as a plurality of support portions, and the plurality of support portions may extend in a first direction and may be arranged in a second direction crossing the first direction.

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

[0015] In an embodiment, the mask may be provided as a plurality of masks, the plurality of masks may extend in the first direction and may be arranged in the 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.

[0017] In an embodiment, the support portion may have a symmetrical structure with respect to the central layer.

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

[0019] In an 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 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 an odd number of base layers, and the base layers may have symmetrical thermal expansion coefficients relative to a center layer of the base layers.

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

[0022] In an embodiment, the center layer may include Invar, 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 for manufacturing a mask assembly may include: providing a frame having an opening defined therein; 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. Forming the support portion may include: preparing 2n+1 base members, where n is a natural number of 1 or greater; and bonding the base members to each other by applying pressure to the base members.

[0024] In an embodiment, the step of forming the support portion may further include scratching a surface facing the other base member among the surfaces of each base member.

[0025] In an embodiment, the step of joining the base member may be repeated multiple times. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are included to provide a further understanding of the inventive concept and are incorporated in and constitute a part of this specification. The accompanying 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 is an exploded perspective view illustrating a mask assembly according to an embodiment of the inventive concept;

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

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

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

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

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

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

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

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

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

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

[0038] 11A to 11D are cross-sectional views schematically illustrating some processes of a method of manufacturing a supporting portion according to an embodiment of the inventive concept. DETAILED DESCRIPTION

[0039] The inventive concept will be more fully described herein with reference to the accompanying drawings, in which various example embodiments are shown. However, the inventive concept may be implemented in many different forms and should not be construed as 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. Like reference numerals represent like elements throughout.

[0040] It will be understood that when an element such as a layer, region, or substrate is referred to as being "on" another element, it can be directly on the other element or one or more intervening elements may be present. In contrast, the term "directly" means there are no intervening elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0041] The terms used herein are for the purpose of describing specific embodiments and are not intended to be limiting. As used herein, the singular forms "one (kind / person)" and "said (the)" are intended to include plural forms comprising "at least one", unless the content clearly indicates otherwise. "Or" means "and / or". As used herein, the term "and / or" includes any combination and all combinations of one or more related listed items. It will also be understood that when the terms "comprises", "comprising" and / or their variations are used in this specification, it is indicated that the features, regions, wholes, steps, operations, elements and / or components are present, but the presence or addition of one or more other features, regions, wholes, steps, operations, elements, components and / or their groups is not excluded.

[0042] For ease of description, spatially relative terms such as “under,” “below,” “down,” “above,” “on,” etc. may be used herein to describe the relationship of one element or feature to another (other) element or feature as shown in the drawings. It will be understood that, in addition to the orientation depicted in the drawings, the spatially relative terms are intended to encompass different orientations of the device in use or operation. For example, if the device in the drawings is flipped, an element described as “under” or “beneath” other elements or features will subsequently be positioned as “above” the other elements or features. Thus, the exemplary term “under” may encompass both the orientations of above and below. The device may be positioned otherwise (e.g., rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein 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 portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Thus, a first element, component, region, layer, or portion discussed below may be referred to as a second element, component, region, layer, or portion without departing from the teachings herein.

[0044] As used herein, “about” or “approximately” is inclusive of the stated value and means within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art, taking into account the measurements involved and errors associated with measurement of the particular quantity (e.g., limitations of the measurement system).

[0045] Example embodiments may be described herein with reference to cross-sectional views and / or plan views that may be idealized exemplary views. In the accompanying drawings, the thicknesses of layers and regions may be exaggerated for clarity. Therefore, variations in the shapes of the illustrations due to, for example, manufacturing techniques and / or tolerances are to be expected. Therefore, the example embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include deviations in shapes due to, for example, manufacturing. For example, an etched region shown as a rectangle will typically have rounded or curved features. Therefore, the regions shown in the accompanying drawings are schematic in nature, and their shapes are not intended to illustrate the actual shape of regions of the device and are not intended to limit the scope of the example embodiments.

[0046] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the exemplary embodiments of the inventive concepts belong. It will also be understood that terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

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

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

[0049] Reference Figure 1 , the mask assembly MA may be used in a process of depositing a deposition material. In an embodiment 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 may have a ring shape or a loop shape. In other words, the opening OP may be provided in a region of the frame FR (such as a region including the center). The opening OP may be a hole penetrating the frame FR from the top surface of the frame FR to the bottom surface of the frame FR.

[0051] exist Figure 1 , 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 thereto. In some embodiments, the frame FR may have at least one of other various shapes such as a circular ring shape and a polygonal ring shape.

[0052] The support portion SP may be provided on the frame FR. The support portion SP may overlap at least a portion of the opening OP of the frame FR. The support portion SP may divide the opening OP into a plurality of areas.

[0053] In the embodiment, the support portion SP may be provided in plural, and the support portion SP will be described here.

[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 second support portions SP2 may be adjusted according to the size and shape of the region where the deposition material is to be deposited.

[0055] exist Figure 1 In the embodiment, two first support portions SP1 and two second support portions SP2 are shown as an example. However, the number of each of the first support portion SP1 and the second support portion SP2 is not limited thereto. In some embodiments, the number of each of the first support portion SP1 and the second support portion SP2 may be one or three or more.

[0056] In an embodiment, Figure 1 As shown in FIG, the first width of each of the first supporting portions SP1 in the second direction DR2 is equal to the second width of each of the second supporting 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 supporting portions SP1 having a longer length may be greater than the second width.

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

[0058] The mask MK may be provided on the support portion SP. In the embodiment, the mask MK may be provided in plural, and the mask MK will be described here.

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

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

[0061] A plurality of opening patterns OPP may be defined in each of the masks MK. When viewed in a plan view, the plurality of opening patterns OPP may not overlap with the support portion SP and may overlap with the opening OP. The opening pattern OPP may be a through hole that penetrates the mask MK from the top surface of the mask MK to the bottom surface of the mask MK.

[0062] The mask MK may be bonded to the support portion SP. For example, the mask MK may 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 may be bonded to the support portion SP by a bonding member (eg, an adhesive).

[0063] Figure 2 is a cross-sectional view illustrating 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 may provide an enclosed or sealed space. A deposition source S, a stage STG, a movable plate PP, and a mask assembly MA may be disposed in the chamber CHB. The chamber CHB may have at least one door GT. The chamber CHB may be opened and closed via the door GT. A target substrate SUB may enter and exit the chamber CHB via the door GT of the chamber CHB.

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

[0067] The stage STG may be disposed above the deposition source S. The mask assembly MA may be placed on the stage STG. The mask assembly MA may face the deposition source S. The stage STG may overlap with the frame FR of the mask assembly MA and may support the mask assembly MA. The stage STG may not overlap with the opening OP of the frame FR. In other words, the stage STG may be disposed outside a movement path of the deposition material supplied from the deposition source S to the target substrate SUB.

[0068] The target substrate SUB may be disposed on the mask assembly MA, and a deposition material may be deposited onto the target substrate SUB through the opening pattern OPP.

[0069] The moving plate PP may align the target substrate SUB on the mask assembly MA. For example, the moving plate PP may generate an electrostatic force or a magnetic force to move the target substrate SUB. The moving plate PP may be movable up and down or left and right.

[0070] In another embodiment, the moving plate PP may fix the target substrate SUB on the mask assembly MA. Since the target substrate SUB is fixed on the mask assembly MA through the moving plate PP, the accuracy of the deposition process may be improved.

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

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

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

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

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

[0076] The barrier layer 11 may include an inorganic material. The barrier layer 11 may prevent or substantially prevent oxygen or moisture from penetrating into the pixel through the base layer BS. The buffer layer 12 may include an inorganic material. The buffer layer 12 may provide the pixel with a surface energy lower than that of the base layer BS, so that the pixel is stably formed on the base layer BS. Figure 3 In the embodiment, 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 provided in plural, and the barrier layers 11 and the buffer layers 12 may be alternately stacked. In other embodiments, at least one of the barrier layer 11 and the buffer layer 12 may be provided in plural or may be omitted.

[0077] Each of the pixels may include a pixel circuit and a light emitting element. The pixel circuit may include a transistor TR and a capacitor. Figure 3 , one transistor TR is shown as an example.

[0078] The transistor TR may 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 may 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, with a second insulating layer 20 interposed between the control electrode CE and the semiconductor pattern SM.

[0079] The input electrode IE and the output electrode OE may be separated from the control electrode CE, with the third insulating layer 30 and the fourth insulating layer 40 interposed therebetween. The input electrode IE and the output electrode OE may penetrate the second insulating layer 20, the third insulating layer 30, and the fourth insulating layer 40 to be connected to one side and the other side of the semiconductor pattern SM, respectively.

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

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

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

[0083] The 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 be in contact with the sixth insulating layer 60. When viewed in plan, the opening pattern OPP of the mask MK may overlap the opening of the sixth insulating layer 60. A deposition material may pass through the opening pattern OPP of the mask MK and then be deposited on the first electrode E1. For example, the emission layer EL may be formed on the first electrode E1. The deposition material may be a material that forms the emission layer EL. In other words, the emission layer EL may be a deposition material deposited on the target substrate SUB.

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

[0086] Figure 4 is a plan view illustrating a supporting portion according to an embodiment of the inventive concept.

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

[0088] The first length LT1 and the second length LT2 may be adjusted according to the chamber CHB (see Figure 2 ) changes due to changes in the internal temperature. 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 supporting portion SP1 and the second supporting portion SP2 may sag in the direction of gravity. This may degrade deposition reliability.

[0089] Refer again Figure 1 An appropriate range of the thermal expansion coefficient may be changed or selected according to 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 an embodiment of the inventive concept, the first support portion SP1 and the second support portion SP2 can be provided with a certain range (e.g., a predetermined range) of thermal expansion coefficients. Thus, it is possible to prevent or substantially prevent deposition reliability from being degraded due to deformation of the shapes of the first support portion SP1 and the second support portion SP2. The thermal expansion coefficient can be measured using a thermomechanical analyzer (TMA). The thermal expansion coefficient can be measured based on a change in the length of a sample as the length of the sample changes from room temperature to a specific temperature.

[0091] Figure 5 is a cross-sectional view illustrating a supporting portion according to an embodiment of the inventive concept. Figure 5 It can be along Figure 4 A cross-sectional view taken along line II'.

[0092] Reference Figure 5 , the support portion thickness TkS of the first support portion SP1 may be thicker than the frame FR (see Figure 2 ) frame thickness TkF (see Figure 2 ) is much smaller. For example, in the embodiment, the frame thickness TkF (see Figure 2) can be in the range from several centimeters to several tens of centimeters, and the support portion thickness TkS can be in the range from several microns to several hundred microns. For example, the support portion thickness TkS can be in the range from 10 microns to 200 microns. The first support portion SP1 is more likely to be deformed in shape due to thermal expansion than the frame FR. According to an embodiment of the inventive concept, the first support portion SP1 can be controlled to have a thermal expansion coefficient within a certain range (e.g., a predetermined range), and therefore, the shape deformation of the first support portion SP1 can be minimized or reduced. In an embodiment, the second support portion SP2 (see Figure 2 ) may have a structure substantially the same as that of the first supporting portion SP1, and thus, further description of the second supporting portion SP2 will be omitted.

[0093] According to an embodiment of the inventive concept, the first supporting portion SP1 may be a clad structure. The first supporting portion SP1 may include an odd number of base layers, for example, 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 supporting 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 may be disposed on the first surface SF1, and the second outer layer OL2 may be disposed on the second surface SF2. In an embodiment, the first surface SF1 may be in direct contact with the first outer layer OL1, and the second surface SF2 may be in direct contact with the second outer layer OL2. In other words, no other components are 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 may be a composite member integrally formed by combining the surfaces of the first outer layer OL1, the central layer CL, and the second outer layer OL2.

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

[0097] Because the core layer CL, the first outer layer OL1, and the second outer layer OL2 constitute the first supporting portion SP1, the thermal expansion coefficient of the entire first supporting portion SP1 can be easily adjusted. For example, when the core layer CL includes a specific material (e.g., a predetermined material), the thermal expansion coefficient of the entire first supporting 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 include specific materials (e.g., a predetermined material), the thermal expansion coefficient of the entire first supporting portion SP1 can be adjusted by changing the materials of the core layer CL.

[0098] In an embodiment, the first thickness Tk1 of the center layer CL, the second thickness Tk2 of the first outer layer OL1, and the third thickness Tk3 of the second outer layer OL2 may be equal (equal or substantially equal) to each other. In an embodiment, the thermal expansion coefficient of the first support portion SP1 may 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 may have a thickness of 10% to 90% of the support thickness TkS. Each of the second thickness Tk2 and the third thickness Tk3 may have a ratio relative to the support thickness TkS based on the first thickness Tk1. For example, each of the second thickness Tk2 and the third thickness Tk3 may have a thickness of 5% to 45% of the support thickness TkS.

[0100] In an embodiment, the second thickness Tk2 and the third thickness Tk3 may be equal (or substantially equal) to each other. For example, even if the first outer layer OL1 and the second outer layer OL2 may be made of the same material, if the second thickness Tk2 is different from the third thickness Tk3, the amount by which the length of the first outer layer OL1 changes due to temperature may differ from the amount by which the length of the second outer layer OL2 changes due to temperature. In this case, the first supporting portion SP1 may 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 due to temperature may be substantially equal to the amount by which the length of the second outer layer OL2 changes due to temperature. Therefore, the phenomenon of the first supporting portion SP1 warping in a specific direction can be prevented or substantially prevented.

[0101] In an embodiment, the first supporting portion SP1 may have a symmetrical structure relative to the center 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 (or substantially equal) to each other relative to the center layer CL. Furthermore, the thermal expansion coefficients of the first outer layer OL1 and the second outer layer OL2 may be equal to each other relative to the center layer CL.

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

[0103] In an embodiment, the central layer CL may include Invar, and the first and second outer layers OL1 and OL2 may each include 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 above examples. In another embodiment, the central layer CL may include stainless steel, and the first and second outer layers OL1 and OL2 may each include Invar.

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

[0105] Figure 6 is a cross-sectional view illustrating a supporting 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 cladding 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 supporting portion SP1 - 1 may have a symmetrical structure with respect to the center layer CL- 1 and a symmetrical thermal expansion coefficient with respect to the center layer CL- 1 .

[0108] The first thickness Tk1-1 of the center layer CL-1 may 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 may be equal to (equal to or substantially equal to) the third thickness Tk3-1.

[0109] In an embodiment, Figure 6As shown in FIG, the first thickness Tk1-1 is greater 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 greater than the first thickness Tk1-1.

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

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

[0112] In an embodiment, the first support portion SP1-2 may be a cladding 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 symmetrical structure and a symmetrical thermal expansion coefficient relative 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. Figure 5 and Figure 6 Each of the first supporting parts SP1 and SP1-1 described above includes three base layers. Figure 7 , the first supporting portion SP1 - 2 including five base layers is shown as an example.

[0114] pass Figures 5 to 7 The first support portion is described. However, the same as the first support portion, Figure 4 The second support portion SP2 shown in FIG may also include 2n+1 base layers, where n is a natural number of 1 or greater. In addition, the second support portion SP2 may also be a cladding structure.

[0115] Figure 8A is an exploded perspective view illustrating 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, a support portion SP-1, and a mask MK. In an embodiment, each of the support portions SP-1 may be a cladding structure and may include 2n+1 base layers, where n is a natural number of 1 or greater.

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

[0118] One of the supporting portions SP-1 may overlap two adjacent masks MK. In other words, one supporting portion may support two masks.

[0119] Figure 8B is an exploded perspective view illustrating 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, a support portion SP-2, and a mask MK. In an embodiment, each of the support portions SP-2 may be a cladding structure and may include 2n+1 base layers, where n is a natural number of 1 or greater.

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

[0122] When viewed in a plan view, the support portion SP-2 may not overlap with the active area of the mask MK. The active area may refer to an area through which the deposition material passes. Figure 8B In the embodiment, the region in which the opening pattern OPP is provided may be defined as an effective region. Therefore, when viewed in a plan view, the support portion SP-2 may not overlap with the opening pattern OPP.

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

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

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

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

[0127] The mask assembly MA may be formed by combining the frame FR, the support portion SP, and the mask MK with each other ( S400 ).

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

[0129] Reference Figure 10 and Figure 11A , an odd number of base members BM1, BM2 and BM3 may be prepared (S210). Figure 11A , three base members BM1, BM2, and BM3 are shown as an example. The three base members BM1, BM2, and BM3 may include a first base member BM1, a second base member BM2, and a third base member BM3.

[0130] The first base member BM1 may include a first surface SF1a and a second surface SF1b, the second base member BM2 may include a first surface SF2a and a second surface SF2b, and the third base member BM3 may include a first surface SF3a and a second surface SF3b. The second base member BM2, the first base member BM1, and the third base member BM3 may be arranged sequentially in a 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 base member BM1 may have a first thickness Tk-B1, the second base member BM2 may have a second thickness Tk-B2, and the third base member 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 may be adjusted differently. For example, the ratio may be adjusted based on a set range of the coefficient of thermal expansion so that the coefficient of thermal expansion is within the set range of the coefficient of thermal expansion.

[0132] Reference Figure 10 and Figure 11B, at least a portion of the surface of each of the three base members BM1, BM2, and BM3 that faces 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 the scraping member SKM. A rough surface PTT can be formed in the area of the first surface SF1a where the scraping member SKM passes. The rough surface PTT can easily join or combine the three base members BM1, BM2, and BM3 to each other.

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

[0134] Reference Figure 10 and Figure 11C In an embodiment, the three base members BM1, BM2, and BM3 may be disposed between bonding rollers BR. The bonding rollers BR may apply pressure to the three base members BM1, BM2, and BM3 to bond the three base members BM1, BM2, and BM3 to each other (S230).

[0135] In the embodiment, the process of joining the base members BM1, BM2, and BM3 by using the joining roller BR may be repeated multiple times. Figure 11D , the first supporting portion SP1 having a supporting portion thickness TkS may be formed.

[0136] In embodiments, heat may be applied to the bonding rollers BR. For example, the bonding rollers BR may apply heat and pressure to the base members BM1, BM2, and BM3. In embodiments, the environment in which the base members BM1, BM2, and BM3 are pressed by the bonding rollers BR may have a predetermined temperature range. In this case, the base members BM1, BM2, and BM3 may be bonded to each other in an environment having a predetermined temperature range. In other words, the process of applying pressure to the base members BM1, BM2, and BM3 while applying heat may be referred to as a hot rolling process.

[0137] The process of forming the first supporting portion SP1 using the base members BM1, BM2, and BM3 may further include a cold rolling process. The cold rolling process may be a process of applying pressure to the base members BM1, BM2, and BM3 at room temperature.

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

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

[0140] Although 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 may be made without departing from the spirit and scope of the inventive concept. Therefore, it should be understood that the above-described embodiments are not limiting, but illustrative. The scope of the inventive concept is therefore to 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, comprising: a frame defining an opening therein; a first supporting portion, located on the frame, overlapping the opening and extending in a first direction; a second supporting portion located on the frame, overlapping the opening and extending in a second direction intersecting the first direction; as well as a mask positioned on the first supporting portion and the second supporting portion and covering at least a portion of the opening, Wherein, each of the first supporting portion and the second supporting portion comprises: Central layer; a first outer layer located on the 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; wherein the magnetic force of the central layer is greater than the magnetic force of each of the first outer layer and the second outer layer, wherein the first length of the first supporting portion and the second length of the second supporting portion are different, wherein the first thermal expansion coefficient of the first supporting portion is different from the second thermal expansion coefficient of the second supporting portion, wherein each of the first supporting portion and the second supporting portion has a symmetrical structure relative to the central layer, and Wherein, the first outer layer and the second outer layer have the same thickness.

2. The mask assembly according to 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 according to claim 1, wherein: The center layer is bonded to the first outer metal layer, and the center layer is bonded to the second outer metal layer.

4. The mask assembly according to claim 1, wherein: The center layer includes a different material than the first and second outer layers, and the first and second outer layers include the same material.

5. The mask assembly according to claim 1, wherein: The central layer has a coefficient of thermal expansion that is different from a coefficient of thermal expansion of the first outer layer.

6. The mask assembly according to claim 1, wherein: The center layer includes Invar, and each of the first and second outer layers includes stainless steel.

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

8. The mask assembly of claim 1, wherein: Each of the frame and the mask includes Invar.

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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