Deposition mask unit

Abstract

A deposition mask unit is provided, comprising: a deposition mask sheet including a plurality of openings; and a deposition mask frame including a protrusion, wherein the deposition mask sheet can be attached to the deposition mask frame at the protrusion, the protrusion including a supporting portion and a coupling portion protruding from an upper surface of the supporting portion, wherein the upper surface of the coupling portion is curved.

Description

[0001] This application claims priority from Korean Patent Application No. 10-2019-0009497 filed on January 24, 2019, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] The present disclosure relates to a mask unit, and more particularly, to a mask unit for depositing an organic layer in a manufacturing process of a display device. Background Art

[0003] With the development of multimedia, display devices are becoming increasingly important. Therefore, various types of display devices such as organic light emitting displays and liquid crystal displays are being used.

[0004] In a display device, an organic light emitting display may have a patterned emission layer structure according to the design of an organic layer. In an organic light emitting display having a patterned emission layer structure, emission layers emitting light of different colors are respectively provided in a plurality of pixels.

[0005] In an organic light-emitting display, for example, a red organic light-emitting layer for emitting red light, a green organic light-emitting layer for emitting green light, and a blue organic light-emitting layer for emitting blue light can be provided in red sub-pixels, green sub-pixels, and blue sub-pixels, respectively. The organic light-emitting layers can be pattern-deposited in light-emitting regions of the organic light-emitting display using a mask unit (e.g., a fine metal mask (FMM)) in which openings corresponding to the sub-pixels of the organic light-emitting display are respectively defined. Summary of the Invention

[0006] One or more embodiments provide a deposition mask unit that includes a relatively high-resolution pattern, ensures a sufficient contact area for a deposition mask under tension in a process of being fixed to a deposition mask frame, and is not penetrated or torn by welding.

[0007] However, the features of the present disclosure are not limited to the features set forth herein. The above features and other features of the present disclosure will become more apparent to those skilled in the art to which the present disclosure pertains by referring to the detailed description of the present disclosure given below.

[0008] An embodiment of a deposition mask unit includes: a deposition mask sheet including a plurality of openings; and a deposition mask frame including a protrusion, wherein the deposition mask sheet can be attached to the deposition mask frame at the protrusion, the protrusion including a supporting portion and a coupling portion protruding from an upper surface of the supporting portion, and the upper surface of the coupling portion is curved.

[0009] In exemplary embodiments, the deposition mask sheet attached to the deposition mask frame may be spaced apart from the support portion.

[0010] In exemplary embodiments, the deposition mask sheet may have a thickness of about 1 micrometer (μm) to about 100 μm.

[0011] In exemplary embodiments, a maximum height of an upper surface of the bonding portion from an upper surface of the support portion may be equal to a thickness of the deposition mask sheet.

[0012] In an exemplary embodiment, the plurality of openings of the deposition mask sheet pass the deposition material therethrough, and a distance between adjacent openings among the plurality of openings is about 5 micrometers to about 15 micrometers.

[0013] In an exemplary embodiment, the number of openings per square inch may be approximately 1,000,000 or more.

[0014] In an exemplary embodiment, a maximum height of an upper surface of the coupling portion from an upper surface of the support portion may be about 0.01 millimeters (mm) to about 0.03 mm.

[0015] In an exemplary embodiment, the support portion may include a lower surface opposite to an upper surface of the support portion, and the upper surface of the support portion may include a first upper surface portion and a second upper surface portion located at different heights from the lower surface.

[0016] In an exemplary embodiment, a first thickness between the lower surface and the first upper surface portion may be about 15 mm to about 20 mm, and a second thickness between the lower surface and the second upper surface portion may be about 12 mm to about 17 mm.

[0017] In an exemplary embodiment, the support portion may further include a middle side surface connecting the first upper surface portion and the second upper surface portion to each other, the middle side surface being inclined with respect to the lower surface.

[0018] In exemplary embodiments, the supporting portion and the coupling portion may include different materials from each other.

[0019] In exemplary embodiments, the bonding portion may include at least one of aluminum, copper, nickel, and magnesium.

[0020] In an exemplary embodiment, a height of the first upper surface portion from the lower surface may be greater than a height of the second upper surface portion from the lower surface, and the coupling portion may protrude from the first upper surface portion.

[0021] An embodiment of a deposition mask unit includes: a plurality of deposition mask sheets, each of the plurality of deposition mask sheets including a plurality of openings; and a deposition mask frame including a plurality of protrusions, the plurality of deposition mask sheets being respectively attachable to the deposition mask frame at the plurality of protrusions, the plurality of protrusions being separated from each other by a plurality of recesses in a first direction, wherein each of the plurality of protrusions includes a supporting portion and a coupling portion protruding from an upper surface of the supporting portion, and the deposition mask sheets attached to the deposition mask frame among the plurality of deposition mask sheets are arranged to be in contact with the coupling portion and separated from the supporting portion.

[0022] In exemplary embodiments, the convex portions and the concave portions may alternate with each other in the first direction.

[0023] In exemplary embodiments, the deposition mask sheets attached to the deposition mask frame among the plurality of deposition mask sheets may be spaced apart from each other in the first direction.

[0024] In exemplary embodiments, the deposition mask sheets attached to the deposition mask frame may respectively provide recessed portions between adjacent deposition mask sheets among the deposition mask sheets.

[0025] In exemplary embodiments, an upper surface of the bonding portion may be curved, and the deposition mask sheet attached to the deposition mask frame may be welded to the upper surface of the bonding portion.

[0026] In exemplary embodiments, the deposition mask frame defines an open area, and the deposition mask sheet attached to the deposition mask frame overlaps the open area.

[0027] In example embodiments, the plurality of deposition mask sheets may include Invar. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] These features and / or other features will become clearer and more easily understood through the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0029] Figure 1 is a schematic perspective view of an embodiment of a mask unit;

[0030] Figure 2 yes Figure 1 A perspective view of an embodiment of a mask frame of a mask unit;

[0031] Figure 3 yes Figure 1 A perspective view of an embodiment of a mask sheet of a mask unit;

[0032] Figure 4 yes Figure 3 an enlarged top plan view of a portion FF1;

[0033] Figure 5 and Figure 6 It is schematically shown Figure 1 A perspective view of an embodiment of a manufacturing sequence of a mask unit;

[0034] Figure 7 It is along Figure 2 A sectional view taken along line II';

[0035] Figure 8 is a cross-sectional view illustrating an embodiment of a process of applying tension to a mask sheet and welding;

[0036] Figure 9 is a cross-sectional view of a modified embodiment of a mask frame of a mask unit;

[0037] Figure 10 is a cross-sectional view of another modified embodiment of a mask frame of a mask unit;

[0038] Figure 11 is a perspective view of another embodiment of a mask frame of a mask unit;

[0039] Figure 12 It is along Figure 11 A sectional view taken along line II-II';

[0040] Figure 13 is a perspective view of yet another embodiment of a mask frame in a mask unit;

[0041] Figure 14 It is along Figure 13 A sectional view taken along line III-III';

[0042] Figure 15 is a perspective view of yet another embodiment of a mask frame of a mask unit;

[0043] Figure 16 It is along Figure 15 A cross-sectional view taken along line IV-IV'; and

[0044] Figure 17 is a cross-sectional view of another embodiment of a mask frame of a mask unit. DETAILED DESCRIPTION

[0045] The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. However, the invention can be embodied in 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 invention to those skilled in the art.

[0046] It will also be understood that when an element is referred to as being associated with another element (such as being "on" another layer or substrate), the element can be directly on the other layer or substrate, or intervening layers may also be present. In contrast, when an element is referred to as being directly associated with another element (such as being "directly on" another element), there are no intervening elements present.

[0047] It will be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first element discussed below can be named the second element without departing from the teachings of the invention. Similarly, the second element can also be named the first element.

[0048] The terms used herein are only for the purpose of describing specific embodiments and are not intended to be restrictive. As used herein, unless the context clearly indicates otherwise, the singular forms "one", "one (kind / person)" and "the (the)" are intended to include plural forms (including "at least one"). "At least one" should not be interpreted as limiting "one" or "one (kind / person)". "Or" means "and / or". As used herein, the term "and / or" includes any combination and all combinations of one or more of the relevant listed items. It will also be understood that when the terms "include" and / or "comprising" or variations thereof are used in this specification, the existence of stated features, regions, wholes, steps, operations, elements, components and / or their groups is indicated, but the existence or addition of one or more other features, regions, wholes, steps, operations, elements, components and / or their groups is not excluded.

[0049] In addition, relative terms such as "lower" or "bottom" and "upper" or "top" may be used herein to describe the relationship of one element to another element as shown in the figures. It will be understood that relative terms are intended to cover different orientations of the device in addition to the orientation depicted in the figures. For example, if the device in a figure is turned over, an element described as being "on the "lower" side of another element will subsequently be positioned as being "on the "upper" side of the other element. Thus, depending on the specific orientation of the figure, the exemplary term "lower" can cover both "lower" and "upper" orientations. Similarly, if the device in a figure is turned over, an element described as being "below" or "beneath" another element will subsequently be positioned as being "above" the other element. Thus, the exemplary terms "below..." or "below..." can cover both "upper" and "lower" orientations.

[0050] 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 in question and errors associated with the measurement of the particular quantity (i.e., limitations of the measurement system). For example, "about" can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, or ±5% of the stated value.

[0051] 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 this disclosure belongs. It will also be understood that terms (such as those defined in common dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and in this disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0052] Exemplary embodiments are described herein with reference to cross-sectional views which are schematic diagrams of idealized embodiments. As such, variations in the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are to be expected. Therefore, the embodiments described herein should not be construed as limited to the specific shapes of the regions as shown herein, but rather are to include deviations in shape due to, for example, manufacturing. For example, a region shown or described as flat may typically have rough and / or nonlinear features. Furthermore, sharp angles shown may be rounded. Therefore, the regions shown in the figures are schematic in nature, and the shapes of these regions are not intended to illustrate the precise shapes of the regions, nor are they intended to limit the scope of the claims.

[0053] The deposition mask unit according to one or more embodiments can be used in a deposition process, such as depositing an organic material layer and / or an inorganic material layer of a display device on a substrate of the display device. The deposition mask unit may include a deposition mask frame to which one or more deposition masks can be fixed. For ease of description, the above-mentioned deposition mask unit, deposition mask frame, and deposition mask are referred to as a mask unit, a mask frame, and a mask sheet throughout this disclosure.

[0054] The display device may be an organic light-emitting display, a liquid crystal display, or a micro-light-emitting diode ("LED") display. The deposition mask unit may be used to deposit an organic light-emitting layer or an organic thin film (such as a hole injection layer / hole transport layer or an electron injection layer / electron transport layer) of an organic light-emitting display as an example display device, and may also be used to deposit other organic films, inorganic films, metal patterns, etc. of the display device.

[0055] Hereinafter, embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. In the accompanying drawings, the same elements will be represented by the same or similar reference numerals.

[0056] Figure 1 is a schematic perspective view of an embodiment of a mask unit 1 . Figure 2 yes Figure 1 FIG. 1 is a perspective view of an embodiment of a mask frame 10 of a mask unit 1 . Figure 3 yes Figure 1 FIG. 1 is a perspective view of an embodiment of a mask sheet 20 a of a mask unit 1 . Figure 4 yes Figure 3 An enlarged top plan view of portion FF1.

[0057] Reference Figures 1 to 4 The mask unit 1 is mainly composed of a mask frame 10 having a rectangular shape and a plurality of mask sheets 20 , each of which is shaped like a flat plate having a predetermined thickness and mountable on the mask frame 10 .

[0058] The mask frame 10 may define an area through which the deposition material passes. That is, the mask frame 10 may define its plane area as a deposition area, where the deposition material passes through the mask frame 10 to be disposed on the target substrate below the mask frame 10. Here, a plurality of mask sheets 20 may be arranged and fixed on the upper surface of the mask frame 10. Specifically, the mask sheet 20a among the plurality of mask sheets 20 may be positioned under the tension F (see FIG. Figure 6 ) is applied to the mask sheet 20a and fixed on the mask frame 10 at the same time.

[0059] The mask frame 10 is a rectangular frame having a substantially rectangular first opening region 350 at the center thereof, and includes a first member 310, a second member 320, a third member 330, and a fourth member 340 connected to one another to form the rectangular frame. The first member 310 and the third member 330 may face each other across the first opening region 350 and may be vertically connected to the second member 320 and the fourth member 340, respectively. Here, the second member 320 and the fourth member 340 may face each other across the first opening region 350.

[0060] The first member 310 and the third member 330 may correspond to the relatively long sides of the rectangular frame extending longitudinally in the first direction dr1, and the second member 320 and the fourth member 340 may correspond to the relatively short sides of the rectangular frame extending longitudinally in the second direction dr2. Here, the first direction dr1 and the second direction dr2 may be understood as directions intersecting each other. Furthermore, the third direction dr3 may be the thickness direction of the mask unit 1 and may be understood as a direction intersecting both the first direction dr1 and the second direction dr2.

[0061] Before manufacturing the mask unit 1, the mask sheet 20a may be in the form of a strip separated from the mask frame 10. Here, the mask unit 1 may include a plurality of mask sheets 20a. More than one mask sheet 20a may be arranged adjacent to each other in the first direction dr1. Each mask sheet 20a may be a fine metal mask ("FMM") having a plurality of openings (first openings 2201, 2202, 2203, and 2204), and the plurality of openings (first openings 2201, 2202, 2203, and 2204) are arranged in a pattern corresponding to a thin film pattern to be provided or formed on a target substrate.

[0062] Each mask sheet 20a includes a main body, which includes main body portions 241, 242, and 250, deposition portions 211 and 212, dummy portions 231 and 232, and bonding portions 221 and 222. The main body portions 241, 242, and 250 and the bonding portions 221 and 222 can be solid planar regions of the main body (e.g., without openings). The deposition portions 211 and 212 are planar regions of the main body that include openings alternating with solid portions of the main body, thereby forming a matrix of openings separated by solid portions of the main body. The dummy portions 231 and 232 can also be planar regions of the main body that include openings separated by solid portions of the main body. The main body portions 241, 242, and 250, the deposition portions 211 and 212, the dummy portions 231 and 232, and the bonding portions 221 and 222 together define the entire mask sheet 20a.

[0063] The main body of the mask sheet 20a can be provided or formed in the shape of a plate having relatively long sides and relatively short sides. At least one of the opposite ends of the main body can be recessed. In an embodiment, for example, the recess can be defined in at least one of the relatively short sides of the main body, such as defined at the main body portion 241 or 242. Figure 3 For example, at least one of the relatively short sides of the main body at the main body portion 241 or 242 may include a linear portion 14 provided or formed as a straight line and a recessed portion 15 extending from the linear portion 14. The recessed portion 15 may be recessed from the linear portion 14 in a direction from the first end of the main body at the main body portion 241 toward the second end of the main body at the main body portion 242, or may be recessed from the linear portion 14 in a direction from the second end of the main body at the main body portion 242 toward the first end of the main body at the main body portion 241. The recessed portion 15 may have an arc shape in a top plan view. In an embodiment, for example, the shape of the recessed portion 15 in a top plan view may be a portion of an ellipse or a portion of a circle.

[0064] The deposition portions 211 and 212 may be alternately arranged with the body portions 241, 242, and 250. Each of the deposition portions 211 and 212 may include a plurality of first openings 2201, 2202, 2203, and 2204, which may be arranged to form a first region 2100. The first region 2100 may include a cluster of first openings 2201, 2202, 2203, and 2204 arranged to be separated from each other by the solid portion of the body, or may be formed by a cluster of first openings 2201, 2202, 2203, and 2204 arranged to be separated from each other by the solid portion of the body. The first openings 2201, 2202, 2203, and 2204 may pass through the deposition portions 211 and 212 to allow deposition material to pass through the first openings 2201, 2202, 2203, and 2204.

[0065] The first openings 2201, 2202, 2203, and 2204 can have various shapes. In an embodiment, for example, the first openings 2201, 2202, 2203, and 2204 can have polygonal planar shapes such as circles, squares, or diamonds. The following will mainly describe in detail the case where the first openings 2201, 2202, 2203, and 2204 are octagons in a top plan view. The deposition portions 211 and 212 can be disposed in the central portion of the main body. Specifically, one or more deposition portions 211 and 212 can be alternately disposed with the main body portions 241, 242, and 250.

[0066] In an embodiment, when the first openings 2201, 2202, 2203, and 2204 are octagonal, the distance between the facing sides may be about 20 micrometers (μm) to about 21 μm. The distance L1 between the first openings 2201, 2202, 2203, and 2204 adjacent to each other in the first direction dr1 may be, but is not necessarily, equal to the distance L1 between the first openings 2201, 2202, 2203, and 2204 adjacent to each other in the second direction dr2. The distance between adjacent first openings 2201, 2202, 2203, and 2204 (the distance L1 between the first openings 2201, 2202, 2203, and 2204 adjacent to each other in the first direction dr1 and the distance L1 between the first openings 2201, 2202, 2203, and 2204 adjacent to each other in the second direction dr2) may be about 5 μm to about 15 μm and may correspond to the distance between pixels of the display device. That is, the pattern of the first openings 2201, 2202, 2203 and 2204 may correspond to the pattern of a thin film to be disposed in pixels of a display device. In an embodiment, the number of first openings 2201, 2202, 2203 and 2204 may correspond to the number of pixels of the display device.

[0067] The dummy portions 231 and 232 may be provided at opposite ends of the main body. Each of the dummy portions 231 and 232 may include a plurality of second openings. The second openings may be arranged in a second region (not shown) similar to the first region 2100 described above. In an embodiment, each of the dummy portions 231 and 232 may be defined as a second region comprising or formed of a cluster of second openings separated from each other by a solid portion of the main body.

[0068] In an embodiment, the second area may be rectangular in shape when viewed from above. The dummy portions 231 and 232 may be separated from the end edges of the body defined by the recessed portion 15 and the linear portion 14 at the main body portions 241 and 242, respectively. Alternatively, the dummy portions 231 and 232, each including a second opening separated from each other by the solid portion of the body, may extend to the end edges of the body, and the main body portions 241 and 242, which are solid portions, may be omitted. The boundaries of each of the dummy portions 231 and 232 at the opposite ends of the body may correspond to or be defined by the linear portion 14 and the recessed portion 15. Within the boundaries of each of the dummy portions 231 and 232, the portion corresponding to the recessed portion 15 may be arc-shaped.

[0069] The dummy portions 231 and 232 may be spaced apart from the deposition portions 211 and 212 along the length of the body. In addition, a pair of dummy portions 231 and 232 may be disposed to face each other relative to the deposition portions 211 and 212 along the length of the body.

[0070] Each mask sheet 20a includes a planar region without an opening between the dummy portions 231 and 232 and the deposition portions 211 and 212, respectively. The bonding portions 221 and 222 may be located between the dummy portions 231 and 232 and the deposition portions 211 and 212, respectively, and may be defined as a solid portion of the mask sheet 20a that can be attached to the mask frame 10. Alternatively, a pair of bonding portions 221 and 222 may be provided in a single mask sheet 20a and may face each other along the length of the body relative to the deposition portions 211 and 212. The pair of bonding portions 221 and 222 facing each other in a single mask sheet 20a may be attached to the first member 310 and the third member 330, respectively, of the mask frame 10.

[0071] The mask sheet 20a may include a mask material. Suitable examples of the mask material include chromium (Cr), molybdenum (Mo), titanium (Ti), tin (Sn), gold (Au), nickel (Ni), nickel alloys, and nickel-cobalt alloys.

[0072] In some embodiments, the mask sheet 20a may include an Invar alloy. The Invar alloy may be an alloy of iron and nickel. In one embodiment, for example, the nickel content of the Invar alloy may be approximately 36 percent (36 wt%), and the iron content may be approximately 64 percent (64 wt%) relative to the total weight of the mask sheet 20a. However, the nickel and iron contents are not limited to these exemplary values and may vary as needed. In addition to nickel and iron, the Invar alloy may also include impurities such as carbon and sulfur.

[0073] The mask sheet 20a can be manufactured by processing a base material (not shown). In an embodiment, for example, the base material can be formed into the mask sheet 20a after undergoing a manufacturing process such as electroforming, electroless plating, laser processing of a thin film base material, a hybrid method using both electroplating and laser processing, rolling, etching, etc.

[0074] In an embodiment, the mask unit 1 can be used in a method for manufacturing a display device to manufacture a display device having a relatively high resolution of 1000 pixels per inch (ppi) or higher. This means that since the number of first openings 2201, 2202, 2203, and 2204 can correspond to the number of pixels of the display device, the number of first openings 2201, 2202, 2203, and 2204 per square inch in one mask sheet 20a can be about 1,000,000 or more. That is, the mask sheet 20a can correspond to a relatively high-resolution display device. The pixels of the display device can correspond to the first openings 2201, 2202, 2203, and 2204 of the mask sheet 20a in number, pattern, size, etc.

[0075] The mask sheet 20a can be relatively thin. In an embodiment, for example, the thickness of the mask sheet 20a along the third direction dr3 can be about 1 μm to about 100 μm. As the resolution of the display device increases, the distance between adjacent pixels decreases. Because the mask sheet 20a is relatively thin, the distance between the first openings 2201, 2202, 2203, and 2204 can be reduced even in an environment where the deposition incident angle is limited, thereby realizing a display device with relatively high resolution.

[0076] The thickness of the mask sheet 20a may vary depending on the deposition incident angle. In an embodiment, for example, as the deposition incident angle increases, the thickness of the mask sheet 20a may increase. In an embodiment, when the deposition incident angle is approximately 45 degrees, the mask sheet 20a may have a thickness of approximately 5 μm. When the deposition incident angle is approximately 60 degrees, the mask sheet 20a may have a thickness of approximately 8.6 μm.

[0077] The first member 310 and the third member 330 of the mask frame 10 may include a plurality of recessed portions 311 and 331 and a plurality of raised portions 312 and 332 arranged along respective lengths of the first member 310 and the third member 330. Each of the recessed portions 311 and 331 may be located between adjacent ones of the raised portions 312 and 332. With respect to a plane in which the bottom surface of the mask frame 10 is disposed, a thickness of each of the plurality of raised portions 312 and 332 at an outer edge of the mask frame 10 is greater than a thickness of each of the plurality of recessed portions 311 and 331 at an outer edge of the mask frame 10.

[0078] When the mask sheet 20a is attached to the mask frame 10, the mask sheet 20a may overlap the protrusions 312 and 332, respectively. When two elements "overlap" each other, unless otherwise specified, the two elements overlap each other in the thickness direction (e.g., the third direction dr3) of the mask unit 1. The recessed portions 311 and 331 and the protrusions 312 and 332 may be spaced apart from each other in the first direction dr1 and may alternate with each other.

[0079] In the mask unit 1, the mask sheet 20a can overlap the protrusions 312 and 332 of the mask frame 10. Each of the recesses 311 and 331 of the mask frame 10 can be located between one mask sheet 20a and the adjacent mask sheet 20a. The recesses 311 and 331 can be used as reference points when aligning the mask sheet 20a on the mask frame 10 when the mask sheet 20a is attached to the mask frame 10.

[0080] Each of the raised portions 312 and 332 includes a supporting portion 333 and an engaging portion 334 , which will be described later.

[0081] A method of manufacturing the mask unit 1 will now be briefly described.

[0082] Figure 5 and Figure 6 1 is a perspective view schematically showing an example of a manufacturing sequence in a method of manufacturing the mask unit 1 .

[0083] Reference Figure 5 , the mask sheet 20a can be placed on the mask frame 10. Here, a tensile force F can be applied to each of the opposite ends of the mask sheet 20a. When the mask sheet 20a is placed, the mask frame 10 can be placed to overlap the bonding portions 221 and 222 of the mask sheet 20a.

[0084] After the mask sheet 20a is placed on the mask frame 10, the mask sheet 20a can be fixed to the mask frame 10. Here, the mask sheet 20a can be fixed to the mask frame 10 by welding. Specifically, the mask sheet 20a can be welded to the mask frame 10 using a laser welding machine 400. The bonding portions 221 and 222 of the mask sheet 20a, which are respectively provided between the dummy portions 231 and 232 and the deposition portions 211 and 212, can be attached and fixed to the mask frame 10 by welding.

[0085] While welding the mask sheet 20a to the mask frame 10 , tension F may be continuously applied to the mask sheet 20a. By applying the tension F, the main body portions 241 and 242 and the dummy portions 231 and 232 of the mask sheet 20a may extend further than the outer edge of the mask frame 10 .

[0086] Reference Figure 6 After the mask sheet 20a is welded to the mask frame 10, the portion of the main body of the mask sheet 20a that extends further than the outer edge of the mask frame 10 can be removed. This portion may include, but is not limited to, the main body portions 241 and 242 and the dummy portions 231 and 232. The portion of the main body of the mask sheet 20a that extends further than the outer edge of the mask frame 10 can be removed in various ways. In one embodiment, for example, a laser can be used to remove the portion of the main body of the mask sheet 20a that extends further than the outer edge of the mask frame 10. In another embodiment, a cutting blade can be used to remove the portion of the main body of the mask sheet 20a that extends further than the outer edge of the mask frame 10.

[0087] After removing a portion of the main body of the mask sheet 20 a extending further than the outer edge of the mask frame 10 , the mask unit 1 in which the mask sheet 20 a is fixed to the mask frame 10 may be provided.

[0088] Now refer to Figure 7 and Figure 8 The structure of the mask frame 10 for fixing the mask sheet 20a will be described in detail.

[0089] Figure 7 It is along Figure 2 A cross-sectional view taken along line II'. Figure 8 is a cross-sectional view illustrating a tension application and welding process of the mask sheet 20a. Figure 7 and Figure 8 The cross section of the mask frame 10 shown in FIG. 1 is a cross section of any one of the first member 310 and the third member 330 joined to the end portion of the mask sheet 20 a .

[0090] Reference Figure 7 and Figure 8, the mask frame 10 may include or be defined by a supporting portion 333 and a coupling portion 334. More specifically, the protrusions 312 and 332 of the first and third members 310 and 330 each include or be defined by a supporting portion 333 and a coupling portion 334.

[0091] Each of the protrusions 312 and 332 of the mask frame 10 includes an engaging portion 334 defined as a portion in contact with the mask sheet 20 a and a supporting portion 333 serving as a base for the engaging portion 334. That is, the engaging portion 334 may include a contact surface in contact with the mask sheet 20 a, and an upper surface 3341 of the engaging portion 334 may be the contact surface.

[0092] The joint 334 may be convex in cross section. In an embodiment, for example, the joint 334 may protrude in the third direction dr3 from a plane in which the upper surface of the support portion 333 is provided (e.g., the second upper side 3334). That is, the mask frame 10 may include a protrusion on the upper surface of the support portion 333. In an embodiment, the upper surface 3341 of the joint 334 may be curved. That is, the upper surface 3341 of the joint 334 may be a surface that is convexly curved relative to the support portion 333. The shape of the convex surface may be shaped like an arc as a part of a circle or an elliptical arc as a part of an ellipse having a predetermined curvature in cross section. In an embodiment, the curvature of the upper surface 3341 of the joint 334 may be approximately 0.5 millimeters (mm) to approximately 5 millimeters (mm). There may be substantially no boundary or interface between the support portion 333 and the joint 334. For ease of description, the convex surface of the joint 334 is an imaginary line ( Figure 7 The dotted line in FIG) will be indicated as the boundary between the supporting portion 333 and the joining portion 334.

[0093] The cross-section of the support portion 333 can have various shapes. In cross-section, the support portion 333 can include a lower side 3331 and a first upper side 3332 and a second upper side 3334 located at different heights from the lower side 3331. In one embodiment, for example, the support portion 333 can include a first upper side 3332 located at a greater height from the lower side 3331 than a second upper side 3334 located from the lower side 3331. That is, in the support portion 333, the first thickness of the mask frame 10 defined or formed by the first upper side 3332 and the lower side 3331 can be greater than the second thickness of the mask frame 10 defined or formed by the second upper side 3334 and the lower side 3331. In one embodiment, the first thickness can be approximately 15 mm to approximately 20 mm. The second thickness can be approximately 12 mm to approximately 17 mm (e.g., approximately 12 mm to approximately 16 mm). The difference between the first and second thicknesses can be approximately 2 mm to approximately 3 mm.

[0094] The plane in which the first upper side 3332 is disposed and the plane in which the second upper side 3334 is disposed may be, but are not necessarily, substantially parallel to the plane in which the lower side 3331 is disposed. The first upper side 3332 may be positioned closer to the first opening area 350 along the second direction dr2 than the second upper side 3334. That is, the second upper side 3334 may be disposed outside the first upper side 3332 relative to the first opening area 350.

[0095] The support portion 333 may further include an intermediate side 3333 located between the first upper side 3332 and the second upper side 3334 in cross section. The intermediate side 3333 may form an angle with each of the first upper side 3332, the second upper side 3334, and the lower side 3331. As used herein, the angle refers to an acute angle formed with an imaginary straight line extending in the direction in which the lower side 3331 extends (e.g., the second direction dr2).

[0096] The support portion 333 may further include, in cross-section, a first side 3335 connecting the first upper side 3332 and the lower side 3331, and a second side 3336 connecting the second upper side 3334 and the lower side 3331. The first side 3335 may be defined as a side surface located closer to the first opening region 350 than the second side 3336. The first side 3335 and / or the second side 3336 may be inclined relative to the lower side 3331. In embodiments, the angle formed by the first side 3335 and the lower side 3331 may be an obtuse angle, for example, greater than approximately 90 degrees and less than approximately 130 degrees. In some embodiments, the second side 3336 and the lower side 3331 may be substantially perpendicular to each other.

[0097] The lower side 3331, the first upper side 3332, the intermediate side 3333, the second upper side 3334, the first side 3335, and the second side 3336 may respectively include or define the lower surface, the first upper surface portion, the intermediate side surface, the second upper surface portion, the first side surface, and the second side surface of the support portion 333. The cross-sectional shape of the support portion 333 is not limited to the shape shown in the drawings. In some embodiments, the support portion 333 may not include the second upper side 3334 in cross-section, but may include only the first upper side 3332 (i.e., omitting the intermediate side 3333), and the first side 3335 and the second side 3336 may both form a right angle with the lower side 3331.

[0098] The joint portion 334 may be provided or formed on the upper surface of the support portion 333. The joint portion 334 may be provided or formed by a wet etching process or a laser processing process. In the cross section of the mask frame 10, the joint portion 334 may be provided or formed on the first upper surface portion of the support portion 333 including the first upper side 3332 or defined by the first upper side 3332, and may not be provided or formed on the second upper surface portion of the support portion 333 including the second upper side 3334 or defined by the second upper side 3334.

[0099] The joint portion 334 may protrude from the upper surface of the support portion 333 to a height of up to about 0.01 mm to about 0.03 mm. In an embodiment, for example, the height from the first upper side 3332 to the upper surface 3341 of the joint portion 334 may be about 0.01 mm to about 0.03 mm. In some embodiments, the maximum height of the joint portion 334 from the upper surface of the support portion 333 may be substantially equal to the thickness of the mask sheet 20 a.

[0100] In an embodiment, the joint portion 334 and the support portion 333 may include the same material as each other and may be provided or formed at the same time as each other. The joint portion 334 and the support portion 333 of the mask frame 10 may each include a metal material having relatively high rigidity, for example, a metal such as stainless steel. In an embodiment, the support portion 333 may extend to define a protrusion thereof defining the joint portion 334, but is not limited thereto.

[0101] During the bonding of the mask sheet 20a to the mask frame 10, a tensile force F may be applied to the mask sheet 20a. In addition to the direction along the second direction dr2 and away from the first opening area 350, an external force (e.g., in a direction from the end of the mask sheet 20a toward the mask frame 10) may also be applied (e.g., in a direction opposite to the third direction dr3 in the drawing). Figure 8 While applying this external force, the contact surface between the mask sheet 20a and the joint portion 334 of the mask frame 10 can be increased, thereby increasing the welding success rate. That is, even if the mask sheet 20a is relatively thin, the contact surface can be increased to increase the welding success rate relative to the mask frame 10.

[0102] After the mask sheet 20 a is attached to the mask frame 10 through a process such as welding, the mask sheet 20 a may be spaced apart from the support portion 333 of the mask frame 10 .

[0103] Next, other embodiments of the mask unit will be described. Figures 1 to 8 The same elements will not be repeated and will be denoted by the same or similar reference numerals.

[0104] Figure 9is a cross-sectional view of a modified embodiment of a mask frame of a mask unit.

[0105] Reference Figure 9 , a modified embodiment of the mask frame of the mask unit with Figure 7 The mask frame 10 of FIG. 1 is different in the shape of the upper surface of the engaging portion 334_11 .

[0106] The upper surface of the bonding portion 334_11 may be an inclined curved surface. When a tensile force is applied to the mask sheet 20a, the contact surface between the upper surface of the bonding portion 334_11 and the mask sheet 20a may be increased, thereby increasing the welding success rate.

[0107] Figure 10 is a cross-sectional view of another modified embodiment of a mask frame of a mask unit.

[0108] Reference Figure 10 , another modified embodiment of the mask frame of the mask unit is Figure 7 The mask frame 10 of FIG. 1 is different in that the middle side 3333 is omitted.

[0109] The upper surface of the joint portion 334_12 may contact the second upper side 3334 of the support portion 333_1. Since the upper surface of the joint portion 334_12 is curved, when tension is applied to the mask sheet 20a, the contact surface between the upper surface of the joint portion 334_12 and the mask sheet 20a may be increased, thereby increasing the welding success rate.

[0110] Figure 11 FIG. 1 is a perspective view of another embodiment of a mask frame 10_1 of a mask unit. Figure 12 It is along Figure 11 A cross-sectional view taken along line II-II'.

[0111] Reference Figure 11 and Figure 12 , the mask frame 10_1 of the mask unit and Figure 2 and Figure 7 The mask frame 10_1 is different in that the mask frame 10_1 includes multiple contact surfaces of the protrusions 312 and 332 that all contact the same mask sheet 20a. The multiple contact surfaces in each of the protrusions 312 and 332 are arranged along the first direction dr1.

[0112] The mask frame 10_1 may include multiple bonding surfaces that contact the same mask sheet 20a. That is, the bonding portion 334_13 may include multiple protrusions that contact the same mask sheet 20a. That is, the positions of the two maximum thicknesses of the bonding portion 334_13 are spaced apart from each other along the first direction dr1.

[0113] The joint portion 334_13 may include a first protrusion 334_1a and a second protrusion 334_1b disposed adjacent to each other in the first direction dr1. The first protrusion 334_1a and the second protrusion 334_1b may be disposed or formed on the first upper surface of the support portion 333. The first protrusion 334_1a and the second protrusion 334_1b may contact the same mask sheet 20a disposed on the first member 310 or the third member 330, respectively. The first protrusion 334_1a and the second protrusion 334_1b may each include a contact region welded to the same mask sheet 20a.

[0114] Each of the first and second protrusions 334_1a and 334_1b may have a shape such as a cylinder cut into a portion having a curved upper surface. However, each of the first and second protrusions 334_1a and 334_1b may have various shapes such as a hemispherical shape as long as the upper surface is curved.

[0115] The upper surface of each of the first protrusion 334_1a and the second protrusion 334_1b may have an arc shape as a portion of a circle in cross section. In an embodiment, the first protrusion 334_1a and the second protrusion 334_1b may be spaced apart from each other along the first direction dr1 with the first upper surface portion of the support portion 333 exposed therebetween, or may be disposed in contact with each other along the first direction dr1.

[0116] The contact surface of each of the first and second protrusions 334_1a and 334_1b with the same mask sheet 20a can be increased by the tension applied to the mask sheet 20a during the setting of the mask unit. That is, when the same mask sheet 20a is bonded to the first and second protrusions 334_1a and 334_1b, the welding success rate can be increased.

[0117] The number and arrangement of the protrusions at each of the protrusions 312 and 332 are not limited to those shown in the drawings. In an embodiment, the engaging portion 334_13 may include three or more protrusions disposed adjacent to each other in the first direction dr1 at each of the protrusions 312 and 332.

[0118] Figure 13 FIG. 1 is a perspective view of yet another embodiment of a mask frame 10_2 of a mask unit. Figure 14 It is along Figure 13 A cross-sectional view taken along line III-III'.

[0119] Reference Figure 13 and Figure 14 , the mask frame 10_2 of the mask unit and Figure 2 and Figure 7The mask frame 10_2 differs from the mask frame 10_2 in that the mask frame 10_2 includes multiple contact surfaces of the raised portions 312 and 332, each of which contacts the same mask sheet 20a. The multiple contact surfaces within each of the raised portions 312 and 332 are arranged along the second direction dr2. In other words, the two locations of maximum thickness of the joint portion 334_2 are spaced apart from each other along the second direction dr2.

[0120] The mask frame 10_2 may include a plurality of engaging surfaces that contact the same mask sheet 20 a . That is, the engaging portion 334_2 may include a plurality of protrusions 334_2 a and 334_2 b that contact the same mask sheet 20 a .

[0121] The joint portion 334_2 may include a first protrusion 334_2a and a second protrusion 334_2b disposed adjacent to each other in the second direction dr2. The first protrusion 334_2a and the second protrusion 334_2b may be disposed or formed on the first upper surface of the support portion 333. The first protrusion 334_2a and the second protrusion 334_2b may contact the same mask sheet 20a. The first protrusion 334_2a and the second protrusion 334_2b may each include a contact region welded to the same mask sheet 20a.

[0122] The first protrusion 334_2a and the second protrusion 334_2b may be continuously arranged, ie, arranged to contact each other in the second direction dr2.

[0123] During the mask unit setting, the contact surface of each of the first protrusion 334_2a and the second protrusion 334_2b with the same mask sheet 20a can be increased by applying tension to the same mask sheet 20a. That is, when the same mask sheet 20a is bonded to the first protrusion 334_2a and the second protrusion 334_2b, the welding success rate can be increased.

[0124] The number and arrangement of the protrusions are not limited to those shown in the drawings. In an embodiment, the engaging portion 334_2 may include three or more protrusions disposed adjacent to each other in the second direction dr2.

[0125] Figure 15 FIG. 1 is a perspective view of yet another embodiment of a mask frame 10_3 of a mask unit. Figure 16 It is along Figure 15 A sectional view taken along line IV-IV'.

[0126] Reference Figure 15 and Figure 16 , the mask frame 10_3 of the mask unit and Figure 2 and Figure 7 The difference between the mask frame 10_3 and the mask frame 10_3 is that the mask frame 10_3 includes a plurality of contact surfaces that come into contact with the same mask sheet 20a.

[0127] The mask frame 10_3 may include multiple bonding surfaces that all contact the same mask sheet 20a. That is, the bonding portion member 334_3 may include multiple bonding portions 334_3a and 334_3b that all overlap the same support portion 333. Each of the bonding portions 334_3a and 334_3b may include multiple protrusions 334_3ba and 334_3bb that all contact the same mask sheet 20a.

[0128] The joint member 334_3 may include a first joint portion 334_3a and a second joint portion 334_3b disposed adjacent to each other in the first direction dr1. The first joint portion 334_3a and the second joint portion 334_3b may both be disposed or formed on the first upper surface of the support portion 333. The first joint portion 334_3a and the second joint portion 334_3b may both contact the same mask sheet 20a. The first joint portion 334_3a and the second joint portion 334_3b may each include a contact region welded to the same mask sheet 20a.

[0129] Each of the first engaging portion 334_3a and the second engaging portion 334_3b may include a first protrusion 334_3ba and a second protrusion 334_3bb. The upper surface of each of the first protrusion 334_3ba and the second protrusion 334_3bb may have an arc shape in cross section. The first protrusion 334_3ba and the second protrusion 334_3bb may be spaced apart from each other in the second direction dr2 with the first upper surface portion of the support portion 333 interposed therebetween, or the first protrusion 334_3ba and the second protrusion 334_3bb may contact each other in the second direction dr2.

[0130] Figure 17 is a cross-sectional view of another embodiment of a mask frame of a mask unit.

[0131] Reference Figure 17 , the mask frame of the mask unit and Figure 7 The difference of the mask frame 10 is that the support portion 333 and the engagement portion 334_4 include different materials from each other. Figure 17 33 is shown between the support portion 333 and the engagement portion 334_4 to indicate different materials.

[0132] As described above, the support portion 333 may include a metal material having relatively high rigidity, for example, a metal such as stainless steel.

[0133] In an embodiment, the support portion 333 and the joint portion 334_4 may include different materials from each other. In an embodiment, for example, the joint portion 334_4 may include any one of aluminum, aluminum alloy, copper, copper alloy, nickel, nickel alloy, magnesium, and magnesium alloy.

[0134] The engaging portion 334_4 may be provided or formed on the upper surface of the supporting portion 333. Figure 17 In the cross section of the mask frame in FIG, the engaging portion 334_4 may be provided or formed on the first upper side 3332, and may not be provided or formed on the second upper side 3334. That is, the engaging portion 334_4 may contact the first upper side 3332 of the support portion 333, and may not contact the second upper side 3334 of the support portion 333.

[0135] The bonding portion 334_4 and the supporting portion 333 may be physically bonded to each other or may be chemically bonded to each other.

[0136] Here, when the engaging portion 334_4 and the supporting portion 333 are physically engaged with each other, the engaging portion 334_4 and the supporting portion 333 are engaged together using a coupling member (eg, a bolt and a nut) or by applying a relatively high pressure to the engaging portion 334_4 and the supporting portion 333 .

[0137] Here, when the bonding portion 334_4 and the supporting portion 333 are chemically bonded to each other, the bonding portion 334_4 and the supporting portion 333 are bonded together by directly forming or depositing a material of the bonding portion 334_4 on the supporting portion 333, by using an adhesive, or by partially melting the bonding portion 334_4 using heat.

[0138] According to one or more embodiments, the mask unit includes a mask sheet having a relatively high-resolution pattern defined therein, which can ensure a sufficient contact area under tension during the process of fixing the mask sheet to the mask frame and can not be penetrated or torn by welding.

[0139] However, the effects of the embodiment are not limited to the effects described herein. The above effects and other effects of the embodiment will become more apparent to those skilled in the art by referring to the claims.

[0140] At the end of the detailed description, those skilled in the art will appreciate that many changes and modifications can be made to the embodiments without departing substantially from the principles of the invention. Therefore, the disclosed embodiments of the invention are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A deposition mask unit, comprising: a deposition mask comprising a plurality of openings, and The deposition mask frame includes a first opening area and a raised portion, the deposition mask sheet spanning the first opening area and being attachable to the deposition mask frame at the raised portion, the raised portion including: a supporting portion; and a coupling portion protruding from an upper surface of the supporting portion, the upper surface of the coupling portion being curved. wherein the deposition mask sheet attached to the deposition mask frame is spaced apart from the supporting portion of the deposition mask frame, and The deposition mask sheet includes a portion extending from the joint portion to an outer end portion of the deposition mask frame away from the first opening region, and the portion is spaced apart from an upper surface of the joint portion.

2. The deposition mask unit according to claim 1, wherein The thickness of the deposition mask sheet is 1 micrometer to 100 micrometers.

3. The deposition mask unit according to claim 2, wherein: A maximum height of the upper surface of the bonding portion from the upper surface of the supporting portion is equal to the thickness of the deposition mask sheet.

4. The deposition mask unit according to claim 1, wherein: The plurality of openings of the deposition mask sheet allow deposition material to pass therethrough, and A distance between adjacent openings among the plurality of openings is 5 micrometers to 15 micrometers.

5. The deposition mask unit according to claim 4, wherein: The number of said openings per square inch is 1,000,000 or more. The deposition mask unit according to claim 1 , wherein: A maximum height of the upper surface of the engaging portion from the upper surface of the supporting portion is 0.01 mm to 0.03 mm.

7. The deposition mask unit according to claim 1, wherein: The supporting portion of the deposition mask frame includes: a lower surface opposite to the upper surface of the support portion, and The upper surface of the support portion includes a first upper surface portion and a second upper surface portion located at different heights from the lower surface.

8. The deposition mask unit according to claim 7, wherein: A first thickness of the deposition mask frame taken between the lower surface and the first upper surface portion is 15 mm to 20 mm, and A second thickness of the deposition mask frame taken between the lower surface and the second upper surface portion is 12 mm to 17 mm.

9. The deposition mask unit according to claim 7, wherein: The support portion further includes an intermediate side surface connecting the first upper surface portion and the second upper surface portion to each other, the intermediate side surface being inclined with respect to the lower surface.

10. The deposition mask unit according to claim 7, wherein: The supporting portion and the engaging portion include materials different from each other.

11. The deposition mask unit according to claim 10, wherein: The bonding portion includes at least one of aluminum, copper, nickel, and magnesium.

12. The deposition mask unit according to claim 7, wherein: The height of the first upper surface from the lower surface is greater than the height of the second upper surface from the lower surface, and The engaging portion protrudes from the first upper surface portion.

13. A deposition mask unit, comprising: a plurality of deposition mask sheets, each of the plurality of deposition mask sheets comprising a plurality of openings; as well as A deposition mask frame includes a first opening area and a plurality of protrusions, wherein the plurality of deposition mask sheets are respectively attachable to the deposition mask frame at the plurality of protrusions across the first opening area, and the plurality of protrusions are separated from each other by a plurality of recesses in a first direction. Each of the plurality of protrusions includes: a supporting portion; and a coupling portion protruding from an upper surface of the supporting portion, wherein the upper surface of the coupling portion is curved, and A deposition mask sheet attached to the deposition mask frame among the plurality of deposition mask sheets is disposed in contact with the coupling portion and spaced apart from the supporting portion, and Each of the plurality of deposition mask sheets includes a portion extending from the coupling portion to an outer end portion of the deposition mask frame away from the first opening region, and the portion is spaced apart from an upper surface of the coupling portion.

14. The deposition mask unit according to claim 13, wherein: The plurality of protrusions and the plurality of depressions alternate with each other in the first direction.

15. The deposition mask unit according to claim 13, wherein: The deposition mask sheets attached to the deposition mask frame among the plurality of deposition mask sheets are spaced apart from each other in the first direction.

16. The deposition mask unit according to claim 15, wherein: The deposition mask sheet attached to the deposition mask frame respectively disposes the plurality of recessed portions between adjacent deposition mask sheets among the deposition mask sheets.

17. The deposition mask unit according to claim 13, wherein: The deposition mask sheet attached to the deposition mask frame is welded to the upper surface of the bonding portion.

18. The deposition mask unit according to claim 13, wherein: The deposition mask sheet attached to the deposition mask frame overlaps the first opening region.

19. The deposition mask unit according to claim 13, wherein: The plurality of deposition mask sheets include Invar alloy.

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