Mask assembly and manufacturing method thereof

Abstract

A mask assembly that can be manufactured using a thin mask substrate and a method for manufacturing the same are provided. [Solution] The mask includes a mask frame having an opening area and a plurality of divided masks arranged on the mask frame, the divided mask including an evaporation pattern portion and an end portion fixed to the mask frame, the evaporation pattern portion including a plurality of opening patterns, and the divided mask having a thickness of 20 μm or less.

Description

[Technical field]

[0001] The present invention relates to a mask assembly and a method for manufacturing the same, and more particularly to a mask assembly manufactured using a thin mask substrate and a method for manufacturing the same. [Background technology]

[0002] An organic light emitting diode display is a self-luminous display device that displays images using organic light emitting elements that emit light. Unlike a liquid crystal display, an organic light emitting diode display does not require a light source and is therefore relatively thin and lightweight. In addition, an organic light emitting diode display has high quality characteristics such as low power consumption, high brightness, and high response speed, and is therefore attracting attention as a next-generation display device for portable electronic devices.

[0003] In an organic light-emitting device, holes and electrons injected into the anode and cathode are recombined in the light-emitting layer to emit light and show a color, and the device has a laminated structure in which the light-emitting layer is inserted between the anode and the cathode. However, since it is difficult to obtain highly efficient light emission with such a structure, intermediate layers such as an electron injection layer, an electron transport layer, a hole transport layer, and a hole injection layer are selectively inserted between each electrode and the light-emitting layer.

[0004] Meanwhile, the electrodes and intermediate layers including the light-emitting layer of the organic light-emitting device can be formed by various methods, one of which is a deposition method. In order to manufacture an organic light-emitting display device using the deposition method, a fine metal mask (FMM) having the same pattern as the thin film pattern formed on the substrate is used. The fine metal mask (FMM) is aligned on the substrate, and a material forming the thin film is deposited on the substrate to pattern the thin film on the substrate.

[0005] At this time, the closer the fine metal mask is to the deposition substrate, the more precise the pattern of the deposited film becomes. Accordingly, in recent years, research has been conducted into manufacturing a mask assembly using a thin mask substrate. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a mask assembly capable of manufacturing a thin mask substrate and a manufacturing method thereof. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, a mask assembly according to one embodiment of the present invention includes a mask frame having an opening area and a plurality of divided masks arranged on the mask frame, the divided masks include a deposition pattern portion and an end portion fixed to the mask frame, the deposition pattern portion includes a plurality of opening patterns, and the divided masks have a thickness of 20 μm or less.

[0008] The ratio d / L of the thickness d of the divided mask to the length L of the opening pattern may be 0.2 or more and 0.7 or less.

[0009] The opening pattern may have a length of not less than 30 μm and not more than 50 μm.

[0010] The segmented mask substrate may be metallic.

[0011] The segmented mask substrate may be an Invar alloy.

[0012] To achieve the above-mentioned object, a manufacturing method of a mask assembly according to another embodiment of the present invention includes preparing a split mask substrate, forming a first photoresist pattern on one side of the split mask substrate, the first photoresist pattern including a first deposition pattern defining a first opening and an auxiliary pattern arranged inside the first opening, forming a second photoresist pattern on the other side of the split mask substrate, half-etching one side of the split mask substrate, applying resin on the half-etched one side of the split mask substrate, and half-etching the other side of the split mask substrate, wherein the auxiliary pattern overlaps the second opening.

[0013] The center of the auxiliary pattern may coincide with the center of the first opening.

[0014] The method may further include removing the first photoresist pattern and the second photoresist pattern after half-etching the other surface of the divided mask substrate.

[0015] The first photoresist pattern may have an area larger than an area of ​​the second photoresist pattern.

[0016] The first photoresist pattern may further include at least one connection portion connecting the first deposition pattern and the auxiliary pattern.

[0017] The connection portion may include a first connection portion, a second connection portion, a third connection portion, and a fourth connection portion.

[0018] The first connection portion and the third connection portion extend in a first direction.

[0019] The second connection portion and the fourth connection portion extend in a second direction intersecting the first direction. Effect of the Invention

[0020] The mask assembly according to the present invention provides the following advantages.

[0021] A mask assembly can be manufactured using a thin mask substrate. In addition, when a mask assembly is manufactured using a thin mask substrate, an opening pattern can be formed precisely. [Brief description of the drawings]

[0022] [Figure 1] 1 is a perspective view of a mask assembly according to an embodiment of the present invention; [Figure 2a] FIG. 2 is a perspective view of a segmented mask according to an embodiment of the present invention. [Figure 2b] 1 is a cross-sectional view of a segmented mask according to an embodiment of the present invention. [Figure 3a] 10A to 10C are diagrams illustrating a manufacturing process of a segment mask according to another embodiment of the present invention. [Figure 3b] 10A to 10C are diagrams illustrating a manufacturing process of a segment mask according to another embodiment of the present invention. [Figure 3c] 10A to 10C are diagrams illustrating a manufacturing process of a segment mask according to another embodiment of the present invention. [Figure 3d] 10A to 10C are diagrams illustrating a manufacturing process of a segment mask according to another embodiment of the present invention. [Figure 3e] 10A to 10C are diagrams illustrating a manufacturing process of a segment mask according to another embodiment of the present invention. [Figure 3f] 10A to 10C are diagrams illustrating a manufacturing process of a segment mask according to another embodiment of the present invention. [Figure 4a] FIG. 3C is a plan view showing the first surface of FIG. 3C according to another embodiment of the present invention. [Figure 4b] FIG. 3C is a plan view showing the second surface of FIG. 3C according to another embodiment of the present invention. [Diagram 5] FIG. 4 is another plan view of the first surface of FIG. 3c according to yet another embodiment of the present invention. [Figure 6] FIG. 4 is yet another plan view showing the first surface of FIG. 3c according to yet another embodiment of the present invention. [Figure 7] 1 is a diagram illustrating deposition on a substrate using a mask assembly according to an embodiment of the present invention. [Figure 8]1 is a cross-sectional view of an organic light emitting display device manufactured using a mask assembly according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The advantages and features of the present invention and the methods for achieving them will become clear with reference to the following detailed description of the embodiments with accompanying drawings. However, the present invention is not limited to the following embodiments, and may be embodied in various different forms, and the embodiments are provided merely to complete the disclosure of the present invention and to fully inform those skilled in the art of the present invention of the category of the invention, and the present invention is defined only by the category of claims. Therefore, in some embodiments, well-known device structures and well-known techniques, such as well-known process steps, are not specifically described to avoid ambiguity in the present invention. The same reference numerals refer to the same components throughout the specification.

[0024] In the drawings, the thickness of many layers and regions is exaggerated for clarity. Similar parts are designated by the same reference numerals throughout the specification. When a layer, film, region, plate, or other part is described as being "on" another part, this includes not only when it is "directly on" the other part, but also when there is another part in between. Conversely, when a part is described as being "directly on" the other part, it means that there is no other part in between. When a layer, film, region, plate, or other part is described as being "under" another part, this includes not only when it is "directly under" the other part, but also when there is another part in between. Conversely, when a part is described as being "directly under" the other part, it means that there is no other part in between.

[0025] Spatially relative terms such as "below," "beneath," "lower," "above," "upper," and the like, may be used to easily describe the relationship of one element or component to another element or component as depicted in the drawings. Spatially relative terms should be understood to include different orientations of elements in use or operation in addition to the orientation depicted in the drawings. For example, if an element depicted in the drawings is turned upside down, an element described as "below" or "beneath" another element may be placed "above" the other element. Thus, the exemplary term "below" can include both an orientation of below and above. Elements may be oriented in other directions, and thus the spatially relative terms may be interpreted accordingly.

[0026] In this specification, terms such as first, second, and third may be used to describe various components, but these components are not limited by the terms. The terms are used for the purpose of distinguishing one component from another component. For example, a first component may be named a second or third component, and similarly, the second and third components may be named interchangeably without departing from the scope of the present invention.

[0027] Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used in a manner commonly understood by a person having ordinary skill in the art to which the present invention belongs. Furthermore, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless they are clearly and specifically defined.

[0028] Hereinafter, an embodiment of the present invention will be described in detail with reference to Fig. 1. Fig. 1 is a perspective view of a mask assembly according to an embodiment of the present invention.

[0029] The mask assembly 10 includes a mask frame 100 and a plurality of segment masks 200 .

[0030] The mask frame 100 may be in a rectangular frame shape having an opening region 101. For example, the mask frame 100 may be in a rectangular frame shape in which two frames extending in the Y direction and facing each other in the X direction, and two frames extending in the X direction and facing each other in the Y direction are connected to each other.

[0031] The mask frame 100 may be made of a rigid metallic material to minimize deformation due to compressive forces or heat acting on the mask frame 100 .

[0032] 1, a plurality of split masks 200 are disposed on a mask frame 100. The split masks 200 may be made of any one of stainless steel (SUS), Invar alloy, nickel (Ni), cobalt (Co), nickel alloy, and nickel-cobalt alloy. By using the above materials for the split masks 200, deformation due to compression force or heat acting on the split masks 200 can be minimized.

[0033] The split mask 200 is arranged on the mask frame 100 in the X direction, and the multiple split masks 200 are arranged consecutively in the Y direction. The split mask 200 can be fixed by welding the ends 216, 217 to the mask frame 100. For example, the welding may be spot welding. In spot welding, multiple welding points are set and welded respectively, thereby minimizing deformation of the split mask 200 during welding. The welding points may be, for example, in at least one column or in a zigzag shape.

[0034] Furthermore, the multiple divided masks 200 can cover the opening region 101 of the mask frame 100 by being continuously arranged in the Y direction.

[0035] FIG. 2a is a perspective view of a segmented mask according to one embodiment of the present invention, and FIG. 2b is a cross-sectional view of the segmented mask according to one embodiment of the present invention.

[0036] Referring to FIG. 2 a , the split mask 200 may include a central portion having a plurality of deposition pattern portions 211 and end portions 216 , 217 fixed to the mask frame 100 .

[0037] 2b, the segmented mask 200 according to an embodiment of the present invention is formed of a thin metal plate. Specifically, the segmented mask 200 is formed of a metal plate having a thickness d of 20 μm or less.

[0038] Furthermore, the opening patterns 212 of the divided mask 200 according to one embodiment of the present invention have a length L of 30 μm or more and 50 μm or less. That is, in the divided mask 200 according to one embodiment of the present invention, the ratio d / L of the thickness d of the divided mask to the length L of the opening patterns 212 may be 0.2 or more and 0.7 or less. Here, the length L of the opening patterns 212 is the length of the divided mask 200 in the first direction (X direction in FIG. 2a).

[0039] The divided mask 200 includes a first surface 201 facing the deposition substrate 300 and a second surface 202 opposite to the first surface 201 .

[0040] The split mask 200 includes deposition pattern portions 211. The deposition pattern portions 211 may be disposed apart from each other in the longitudinal direction (X direction) of the split mask 200.

[0041] Each deposition pattern portion 211 includes a plurality of opening patterns 212. As shown in Fig. 2b, the divided mask 200 is penetrated by the opening patterns 212 in the thickness direction.

[0042] Each of the opening patterns 212 is formed in a shape corresponding to the shape of a thin film to be deposited on the deposition substrate 300 arranged on the divided masks 200. Thus, in the deposition process, a deposition material is deposited on the deposition substrate through the opening patterns 212 to form a thin film of a desired shape. As shown in Figs. 1 and 2a, the opening patterns 212 may be strip-shaped. However, the opening patterns 212 are not limited thereto, and may be various shapes such as a circle, a rectangle, etc.

[0043] According to an embodiment of the present invention, the mask assembly 10 can be manufactured by using a plurality of thin divided masks 200 in which a deposition pattern portion 211 having a precise opening pattern 212 is formed. Since each of the plurality of divided masks 200 is thin, it is possible to improve adhesion between the mask assembly 10 and a deposition substrate 300 disposed on the mask assembly 10. As a result, a precise deposition film pattern can be formed on the deposition substrate 300.

[0044] Hereinafter, a method for manufacturing a segment mask according to another embodiment of the present invention will be described in detail with reference to Figures 3a to 4b. Figures 3a to 3f are views showing a manufacturing process of a segment mask according to another embodiment of the present invention. Figure 4a is a plan view showing a first surface of Figure 3c according to another embodiment of the present invention, and Figure 4b is a plan view showing a second surface of Figure 3c according to another embodiment of the present invention.

[0045] As shown in Fig. 3a, a divided mask substrate 200' is prepared. The divided mask substrate 200' is made of any one of stainless steel (SUS), Invar alloy, nickel (Ni), cobalt (Co), nickel alloy, and nickel-cobalt alloy.

[0046] In this case, the divided mask substrate 200 ′ includes a first surface 201 facing the deposition substrate 300 and a second surface 202 opposite to the first surface 201 .

[0047] Referring to FIG. 3b, a first photoresist 410' is applied to the first surface 201 of the split mask substrate 200', and a second photoresist 420' is applied to the second surface 202 of the split mask substrate 200'.

[0048] Referring to FIG. 3c, a first photoresist 410′ applied to the first surface 201 is patterned to form a first photoresist pattern 410, and a second photoresist 420′ applied to the second surface 202 is patterned to form a second photoresist pattern 420.

[0049] The first photoresist pattern 410 includes a first deposition pattern 411 and an auxiliary pattern 412 .

[0050] The first deposition pattern 411 is formed to define first openings 431 having a shape corresponding to the shape of a thin film to be deposited on a deposition substrate 300 disposed on the plurality of divided masks 200 .

[0051] The auxiliary pattern 412 is disposed within the first opening 431 defined by the first deposition pattern 411. The auxiliary pattern 412 is also disposed within the first opening 431 defined by the first deposition pattern 411. 4a and 4b, the first photoresist pattern 410 may overlap the second opening 432 defined by the photoresist pattern 420. In this case, the first photoresist pattern 410 may have a larger area than the second photoresist pattern 420.

[0052] The second photoresist pattern 420 may be formed to define second openings 432 having a shape corresponding to a thin film shape to be deposited on the deposition substrate 300 disposed on the plurality of divided masks 200. At this time, the second openings 432 overlap with the auxiliary patterns 412.

[0053] 3c, the center C2 of the auxiliary pattern 412 substantially coincides with the center C1 of the first opening 431. That is, the auxiliary pattern 412 can be located at the center of the first opening 431. Therefore, it is possible to prevent the thin divided mask substrate 200' from being excessively etched during half etching using the first photoresist pattern 410. Note that in this specification and the like, half etching refers to etching the divided mask substrate from the top surface while leaving a predetermined thickness.

[0054] In the method for manufacturing the mask assembly 10 according to the embodiment of the present invention, an auxiliary pattern 412 is formed at the center of the first opening 431 so that the split mask substrate 200' is not penetrated during half etching using the first photoresist pattern 410. This allows for the formation of a precise opening pattern 212. As a result, a thin split mask 200 having a precise opening pattern 212 can be formed.

[0055] 3d, the first surface 201 of the split mask substrate 200′ is half-etched according to the first photoresist pattern 410. Specifically, a first groove 451 is formed corresponding to the first opening 431 formed by the first photoresist pattern 410. At this time, the first groove 451 may have a predetermined depth from the first surface 201 without penetrating the split mask substrate 200′.

[0056] 3e, a resin 500 is applied onto the first surface 201 in which the first grooves 451 are formed. At this time, the resin 500 may cover the entire surface of the first surface 201 of the divided mask substrate 200′. Specifically, the resin 500 may cover the first surface 201 including the first grooves 451.

[0057] 3f, the second surface 202 of the split mask substrate 200' is half-etched according to the second photoresist pattern 420. Specifically, second grooves 452 are formed in the second surface 202 corresponding to the second openings 432 formed according to the second photoresist pattern 420. At this time, the split mask substrate 200' is penetrated by the first grooves 451 and the second grooves 452.

[0058] Next, the resin 500 and the first photoresist pattern 410 applied on the first surface 201 of the split mask substrate 200' and the second photoresist pattern 420 applied on the second surface 202 of the split mask substrate 200' are removed. Through the above process, a split mask 200 having an opening pattern 212 formed on a thin split mask substrate 200' as shown in FIG. 2b can be formed.

[0059] Each of the opening patterns 212 may be formed in a shape corresponding to a thin film shape to be deposited on a deposition substrate 300 disposed on the plurality of divided masks 200. Thus, during a deposition process, a deposition material is deposited on the deposition substrate through the opening patterns 212, so that a thin film having a desired shape can be formed.

[0060] When half etching is performed from the first and second surfaces of the divided mask substrate 200', if the auxiliary pattern 412 is not formed, the divided mask substrate 200' may be etched excessively because the divided mask substrate 200' is thin. If the divided mask substrate 200' is etched excessively, the opening pattern may become large or may penetrate through the opening pattern in one etching, making it impossible to form a precise opening pattern.

[0061] According to the method for manufacturing the mask assembly shown in FIG. 3a to FIG. 3f, the first opening 431 is formed on the second surface 202 of the split mask substrate 200', and the auxiliary pattern 412 located at the center of the first opening 431 is formed on the first surface 201. By forming the auxiliary pattern 412 on the first surface 201, excessive etching can be prevented when half-etching the first surface 201 of the split mask 200'. In addition, by half-etching the second surface 202 with the second photoresist pattern 420, the split mask substrate 200' can be penetrated. As a result, a precise opening pattern 212 can be formed on the thin split mask substrate, compared to a case where the auxiliary pattern 412 is not formed on the split mask 200'. In addition, the mask assembly 10 can be manufactured by using a plurality of mask substrates on which opening patterns are precisely formed.

[0062] According to one embodiment of the present invention, the length L of the opening pattern 212 is 30 μm or more and 50 μm or less. Also, according to one embodiment of the present invention, the divided mask substrate 200′ has a thickness of 20 μm or less. That is, the divided mask substrate 200′ according to one embodiment of the present invention may have a ratio d / L of the thickness d of the opening pattern 212 to the length L of the opening pattern 212 of 0.2 or more and 0.7 or less.

[0063] According to an embodiment of the present invention, the mask assembly 10 may be manufactured using a plurality of thin split masks 200 each having a precise opening pattern 212 formed therein. Since the split masks 200 are thin, the adhesion between the mask assembly 10 and the deposition substrate 300 disposed on the mask assembly 10 may be improved. As a result, the deposition material may be deposited on the deposition substrate 300 with precision.

[0064] Hereinafter, a further embodiment of the present invention will be described in detail with reference to Fig. 5. Fig. 5 is another plan view of Fig. 3c according to a further embodiment of the present invention. For convenience of explanation, the description of the same configuration as the other embodiment of the present invention will be omitted.

[0065] 5, the first photoresist pattern 410 includes at least one connection portion 413 connecting the first deposition pattern 411 and the auxiliary pattern 412. For example, as shown in FIG 5, the first photoresist pattern 410 may include a first connection portion 413a, a second connection portion 413b, a third connection portion 413c, and a fourth connection portion 414d.

[0066] The first connection portion 413a may be substantially parallel to the third connection portion 413c, and the second connection portion 413b may be substantially parallel to the fourth connection portion 413d. For example, as shown in FIG. 5, the first connection portion 413a and the third connection portion 413c extend in a first direction D1, and the second connection portion 413b and the fourth connection portion 413d extend in a second direction D2 intersecting with the first direction D1. At this time, the first direction D1 may be perpendicular to the second direction D2. At this time, the first direction D1 may be the longitudinal direction of the divided mask 200 (the X direction in FIG. 1).

[0067] Therefore, the first opening 431 can be divided into four openings 431a, 431b, 431c, and 431d by the first connection portion 413a, the second connection portion 413b, the third connection portion 413c, and the fourth connection portion 413d.

[0068] Hereinafter, still another embodiment of the present invention will be described in detail with reference to FIG. Fig. 3c according to another embodiment of the present invention, and for the sake of convenience, a description of the same configuration as in the other embodiment of the present invention will be omitted.

[0069] 6, the first photoresist pattern 410 includes at least one connection portion 413 connecting the first deposition pattern 411 and the auxiliary pattern 412. For example, as shown in FIG 6, the first photoresist pattern 410 may include a first connection portion 413a, a second connection portion 413b, a third connection portion 413c, and a fourth connection portion 413d.

[0070] The first connection portion 413a may be substantially parallel to the third connection portion 413c, and the second connection portion 413b may be substantially parallel to the fourth connection portion 413d. For example, as shown in FIG. 6, the first connection portion 413a and the third connection portion 413c extend in the third direction D3, and the second connection portion 413b and the fourth connection portion 413d extend in the fourth direction D4 intersecting with the third direction D3. At this time, the third direction D3 may be perpendicular to the fourth direction D4. At this time, referring to FIG. 6, the third direction D3 and the fourth direction D4 may intersect with the first direction D1 and the second direction D2, respectively, while forming an acute angle.

[0071] Therefore, the first opening 431 can be divided into four openings 431a, 431b, 431c, and 431d by the first connection portion 413a, the second connection portion 413b, the third connection portion 413c, and the fourth connection portion 413d.

[0072] By forming the auxiliary pattern 412 shown in FIG. 5 or 6, excessive etching can be prevented when half-etching the first surface 201 of the split mask 200'. Also, by half-etching the second surface 202 with the second photoresist pattern 420, the split mask substrate 200' can be penetrated. As a result, a thinner split mask substrate with a precise opening pattern 212 can be formed compared to a case where the auxiliary pattern 412 is not formed on one surface of the split mask 200'. Also, by using a plurality of mask substrates on which opening patterns are precisely formed, a mask assembly can be manufactured.

[0073] According to one embodiment of the present invention, the length L of the opening pattern 212 is 30 μm or more and 50 μm or less. Also, according to one embodiment of the present invention, the split mask substrate 200' has a thickness of 20 μm or less. That is, the split mask substrate 200' according to one embodiment of the present invention may have a ratio d / L of the thickness d to the length L of the opening pattern 212 of 0.2 or more and 0.7 or less. Here, the length L of the opening pattern 212 is the length in the first direction (X direction in FIG. 2a) of the split mask substrate 200'.

[0074] According to an embodiment of the present invention, the mask assembly 10 may be manufactured using a plurality of thin split masks 200 each having a precise opening pattern 212 formed therein. Since the split masks 200 are thin, the adhesion between the mask assembly 10 and the deposition substrate 300 disposed on the mask assembly 10 may be improved. As a result, the deposition material may be deposited on the deposition substrate 300 with precision.

[0075] Hereinafter, a process of depositing on a deposition substrate 300 using a mask assembly according to an embodiment of the present invention will be described in detail with reference to Fig. 7. Fig. 7 is a diagram showing deposition on a deposition substrate using a mask assembly according to an embodiment of the present invention.

[0076] Referring to FIG. 7, the mask assembly 10 is placed in a vacuum chamber 600 to deposit an organic light-emitting layer or an electrode of an organic light-emitting display device.

[0077] A deposition source 601 is disposed at the bottom of the vacuum chamber 600, and a varistor 602 is disposed above the deposition source 601. 1. The divided mask 200 is placed on the mask frame 100. The deposition substrate 300 is placed on the divided mask 200.

[0078] The deposition source 601 has a heating container (crucible) containing an organic material therein, and can evaporate the organic material by heat and deposit it on the deposition substrate 300. The deposition apparatus may further include a heater (not shown) for heating the organic material. The heaters are provided on both sides of the deposition source 601 and serve to heat the deposition source 601 and heat the organic material contained in the deposition source 601 to sublimate it.

[0079] The vacuum chamber 600 provides a space in which the deposition process proceeds. The vacuum chamber 600 is connected to a vacuum pump (not shown) such as a turbo molecular pump (TMP) to maintain the inside of the vacuum chamber 600 in a vacuum state during the deposition process. The vacuum chamber 600 may further include an adhesion prevention plate (not shown) arranged to surround the inner wall surface. The adhesion prevention plate prevents organic materials ejected from the deposition source 601 that are not deposited on the deposition substrate 300 from being adsorbed onto the inner wall surface of the vacuum chamber 600.

[0080] The support member 602 can secure the mask assembly 10 at the edge of the mask assembly 10 .

[0081] The process of depositing a deposition material on the deposition substrate 300 will now be briefly described.

[0082] First, the mask assembly 10 is fixed on the support member 602 , and the deposition substrate 300 is placed on the fixed mask assembly 10 .

[0083] Then, a deposition material is sprayed from a deposition source 601 located at the bottom of the vacuum chamber 600 toward the deposition substrate 300. In particular, when power is applied to the deposition source 601, the deposition source 601 containing the deposition material is heated, and the deposition material is heated and sublimated, and sprayed toward the mask assembly 10. At this time, the inside of the vacuum chamber 600 is maintained at a high vacuum and a high temperature.

[0084] When a deposition material is sprayed from the deposition source 601 , the deposition material can be deposited on one side of the deposition substrate 300 through the deposition pattern portion (deposition pattern portion 211 in FIG. 1) formed on the divided mask 200 .

[0085] Since the split mask 200 according to an embodiment of the present invention is thin, it is possible to improve the adhesion between the mask assembly 10 and the deposition substrate 300. In addition, the split mask 200 has a deposition pattern portion having a plurality of precise opening patterns 212 formed therein. Therefore, by using the mask assembly 10 having a plurality of the split masks 200, it is possible to deposit a deposition material on the deposition substrate 300 with precision.

[0086] Hereinafter, an organic light emitting display device manufactured using a mask assembly according to an embodiment of the present invention will be described in detail with reference to Fig. 8. Fig. 8 is a cross-sectional view of an organic light emitting display device manufactured using a mask assembly according to an embodiment of the present invention.

[0087] 8, the display panel of the organic light emitting display device according to an embodiment of the present invention includes a plurality of pixels including a switching thin film transistor (not shown), a driving thin film transistor 20, a capacitor element 80, and an organic light emitting diode (OLED) 810. The organic light emitting diode 810 can be deposited at a relatively low temperature and is mainly applicable to flexible display devices due to its low power consumption, high brightness, etc. Here, a pixel refers to the smallest unit for displaying an image, and the display panel displays an image using a plurality of pixels.

[0088] In addition, a structure in which two thin film transistors (TFTs) and one capacitor are arranged in a single pixel will be described, but the present invention is not limited thereto. One pixel may have three or more thin film transistors and two or more capacitors, and may have various structures including additional wiring.

[0089] The display panel may include a base substrate 710, gate lines disposed on the base substrate 710, data lines 771 intersecting the gate lines in an insulated state, and a common power line 772. Generally, one pixel may be defined by the gate lines, the data lines 771, and the common power line 772 as boundaries, but the pixel is not limited to the above definition. The pixel may be defined by a black matrix or a pixel definition film.

[0090] The base substrate 710 may be made of a flexible insulating material. For example, the base substrate 710 may be made of a polymer material such as polyimide (PI), polycarbonate (PC), polyethersulphone (PES), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyarylate (PAR), fiber glass reinforced plastic (FRP), etc. Alternatively, the base substrate 710 may be a glass substrate. The base substrate 710 may be transparent, translucent, or opaque.

[0091] A buffer layer 720 is disposed on a base substrate 710. The buffer layer 720 has a function of preventing the permeation of impurity elements and planarizing the surface, and can be formed of various materials capable of performing such functions. For example, the buffer layer 720 can be formed of silicon nitride (SiN x ) film, silicon oxide (SiO 2 ) film, silicon oxynitride (SiO x N y However, the buffer layer 720 is not necessarily required and may be omitted depending on the type of the base substrate 710 and process conditions.

[0092] A semiconductor layer of the switching thin film transistor and a semiconductor layer 732 of the driving thin film transistor are disposed on the buffer layer 720. The semiconductor layer of the switching thin film transistor and the semiconductor layer 732 of the driving thin film transistor can be formed of any one of a polycrystalline silicon film, an amorphous silicon film, and an oxide semiconductor such as IGZO (Indium-Gallium-Zinc Oxide) and IZTO (Indium Zinc Tin Oxide). For example, when the semiconductor layer 732 of the driving transistor is formed of a polycrystalline silicon film, the semiconductor layer 732 of the driving thin film transistor has a channel region where impurities are not doped, and p-type semiconductors on both sides of the channel region. + The doped ion material is a P-type impurity such as boron (B), and the doped ion material is mainly B. 2 H 6 The impurities vary depending on the type of thin film transistor. In the embodiment of the present invention, a thin film transistor having a PMOS structure using P-type impurities is used as the driving thin film transistor 20, but the driving thin film transistor 20 is not limited thereto. Therefore, the driving thin film transistor 20 may be either a thin film transistor having an NMOS structure or a thin film transistor having a CMOS structure.

[0093] A gate insulating film 740 is disposed on the semiconductor layer of the switching thin film transistor and the semiconductor layer 732 of the driving thin film transistor. The gate insulating film 740 is made of tetraethyl orthosilicate (TEOS), silicon nitride (SiN x ) and silicon oxide (SiO 2 For example, the gate insulating film 740 may have a double-layer structure in which a silicon nitride film having a thickness of 40 nm and a tetraethyl orthosilicate film having a thickness of 80 nm are sequentially stacked.

[0094] A gate electrode 755 and a gate line including the gate electrode 755 are disposed on the gate insulating film 740. The gate line may be electrically connected to a first capacitance electrode 758 and other wiring. The gate electrode 755 is disposed so as to overlap at least a part of the semiconductor layer 732, particularly the channel region. The gate electrode 755 has a function of blocking impurities from being doped into the channel region when impurities are doped into the source region and the drain region of the semiconductor layer 732 in the process of forming the semiconductor layer 732.

[0095] The gate electrode 755 and the first capacitor electrode 758 are disposed in the same layer and are made of substantially the same metal. The gate electrode 755 and the first capacitor electrode 758 may include at least one of molybdenum (Mo), chromium (Cr), and tungsten (W).

[0096] An interlayer insulating film 760 that covers the gate electrode 755 is disposed on the gate insulating film 740. The interlayer insulating film 760 is made of silicon nitride (SiNx), silicon oxide (Si Ox) or tetraethyl orthosilicate (TEOS), but is not limited to these. It is not something that can be achieved.

[0097] A data line 771 including a source electrode 776 or a drain electrode 777 is disposed on the interlayer insulating film 760. The data line 771 may be electrically connected to a common power supply line 772, a second capacitance electrode 778, or other wiring. The source electrode 776 and the drain electrode 777 are connected to the source region and the drain region of the semiconductor layer 732, respectively, via contact holes formed in the gate insulating film 740 and the interlayer insulating film 760.

[0098] The switching thin film transistor (not shown) includes a semiconductor layer (not shown), a gate electrode (not shown), a source electrode (not shown) and a drain electrode (not shown), and the driving thin film transistor 20 includes a semiconductor layer 732, a gate electrode 755, a source electrode 776 and a drain electrode 777. The configuration of the driving thin film transistor 20 is not limited to the above examples and may be variously modified into known configurations that can be easily implemented by those skilled in the art.

[0099] The capacitive element 80 also includes a first capacitive electrode 758 and a second capacitive electrode 778 arranged with an interlayer insulating film 760 sandwiched therebetween.

[0100] Although not shown, the switching thin film transistor is used as a switching element for selecting a pixel to be made to emit light. The gate electrode of the switching thin film transistor is connected to the gate line. The source electrode of the switching thin film transistor is connected to the data line 771. The drain electrode of the switching thin film transistor is disposed apart from the source electrode of the switching thin film transistor and is connected to the first capacitance electrode 758.

[0101] The driving thin film transistor 20 applies a driving power supply to the pixel electrode 811 to cause the light emitting layer 812 of the organic light emitting element 810 in the selected pixel to emit light. The gate electrode 755 is connected to the first capacitance electrode 758. The source electrode 776 and the second capacitance electrode 778 are each connected to a common power line 772. The drain electrode 777 is connected to the pixel electrode 811 of the organic light emitting element 810 through a contact hole.

[0102] With this structure, the switching thin film transistor operates according to a gate voltage applied to the gate line, and transmits a data voltage applied to the data line 771 to the driving thin film transistor 20. A voltage corresponding to the difference between a common voltage applied to the driving thin film transistor 20 from a common power line 772 and the data voltage transmitted from the switching thin film transistor is stored in the capacitance element 80, and a current corresponding to the voltage stored in the capacitance element 80 flows through the driving thin film transistor 20 to the organic light emitting element 810, causing the organic light emitting element 810 to emit light.

[0103] A planarization film 780 is disposed on the interlayer insulating film 760 to cover conductive layers patterned on the same layer, such as the data line 771, the common power line 772, the source electrode 776, the drain electrode 777, the second capacitance electrode 778, etc.

[0104] The planarization film 780 has a function of eliminating steps and planarizing the surface in order to increase the light emitting efficiency of the organic light emitting element 810 formed thereon. The planarization film 780 may be formed of one or more of the following materials: an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, a polyimide resin, an unsaturated polyester resin, a polyphenylene ethers resin, a polyphenylene sulfide resin, and a benzocyclobutene (BCB).

[0105] A pixel electrode 811 of the organic light emitting element 810 is disposed on the planarization film 780. The pixel electrode 811 is connected to the drain electrode 777 via a contact hole formed in the planarization film 780.

[0106] A pixel defining film 790 that exposes at least a part of a pixel electrode 811 and defines a pixel region is disposed on the planarization film 780. The pixel electrode 811 is disposed to correspond to the pixel region of the pixel defining film 790. The pixel defining film 790 can be formed of a resin such as a polyacrylates resin or a polyimides resin. The pixel defining film 790 is also called a bank.

[0107] An emission layer 812 is disposed on a pixel electrode 811 in a pixel region, and a common electrode 813 is disposed on the pixel defining film 790 and the emission layer 812. The emission layer 812 is made of a low molecular weight organic material or a high molecular weight organic material. At least one of a hole injection layer (HIL) and a hole transporting layer (HTL) may be further disposed as an intermediate layer between the pixel electrode 811 and the emission layer 812, and at least one of an electron transporting layer (ETL) and an electron injection layer (EIL) may be further disposed between the emission layer 812 and the common electrode 813. The organic light emitting element 810 includes a pixel electrode 811, an emission layer 812, and a common electrode 813.

[0108] The light emitting layer 812 of the organic light emitting device 810 and the intermediate layer including the light emitting layer 812 may be deposited using the mask assembly 10 according to an embodiment of the present invention. Therefore, the light emitting layer 812 and the intermediate layer including the light emitting layer 812 may be formed in a precise pattern.

[0109] The pixel electrode 811 and the common electrode 813 are formed of any one of a transmissive electrode, a semi-transmissive electrode, and a reflective electrode.

[0110] To form a transparent electrode, a transparent conductive oxide (TCO) can be used. Examples of the transparent conductive oxide (TCO) include ITO (indium tin oxide), IZO (indium zinc oxide), ZnO (zinc oxide), and In2 O 3 (Indium Oxide), etc.

[0111] Metals such as magnesium (Mg), silver (Ag), gold (Au), calcium (Ca), lithium (Li), chromium (Cr), aluminum (Al), and copper (Cu) or alloys thereof can be used to form the semi-transmissive electrode and the reflective electrode. In this case, the semi-transmissive electrode and the reflective electrode are determined by their thickness. In general, the semi-transmissive electrode has a thickness of about 200 nm or less, and the reflective electrode has a thickness of 300 nm or more. The thinner the semi-transmissive electrode, the higher the light transmittance but the higher the resistance, and the thicker the electrode, the lower the light transmittance.

[0112] Also, the semi-transmissive and reflective electrodes can be formed in a multi-layer structure including a metal layer made of a metal or a metal alloy and a transparent conductive oxide (TCO) layer laminated on the metal layer.

[0113] A thin film encapsulation layer 850 is disposed on the common electrode 813. The thin film encapsulation layer 850 includes one or more inorganic films 851, 853, 855 and one or more organic films 852, 854. The thin film encapsulation layer 850 has a structure in which the inorganic films 851, 853, 855 and the organic films 852, 854 are alternately laminated. In this case, the inorganic film 851 is disposed at the bottom. That is, the inorganic film 851 is disposed closest to the organic light emitting element 810.

[0114] The thin film encapsulation layer 850 includes three inorganic films 851, 853, 855 and two organic films 852, 854, although one embodiment of the present invention is not limited in this respect.

[0115] Inorganic films 851, 853, and 855 are Al 2 O 3 , TiO 2 , ZrO, SiO 2 , AlON, AlN, SiON, Si 3 N 4 , ZnO, and Ta 2 O 5The inorganic films 851, 853, and 855 are formed by a chemical vapor deposition (CVD) method or an atomic layer deposition (ALD) method. However, an embodiment of the present invention is not limited thereto, and the inorganic films 851, 853, and 855 can be formed by various methods known to those skilled in the art.

[0116] The organic films 852 and 854 are formed of a polymer-based material. Here, the polymer-based material includes acrylic resin, epoxy resin, polyimide, polyethylene, etc. Also, the organic films 852 and 854 are formed by a thermal evaporation process. Also, the thermal evaporation process for forming the organic films 852 and 854 is performed within a temperature range that does not damage the organic light emitting element 810. However, an embodiment of the present invention is not limited thereto, and the organic films 852 and 854 may be formed by various methods known to those skilled in the art.

[0117] The inorganic films 851, 853, and 855, which are densely formed thin films, mainly suppress the permeation of moisture or oxygen. The inorganic films 851, 853, and 855 can block the permeation of almost all moisture and oxygen into the organic light emitting element 810.

[0118] The thin film encapsulation layer 850 can be formed to a thickness of 10 μm or less, so that the total thickness of the display panel can be made very thin.

[0119] The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and various substitutions, modifications, and alterations are possible within the scope of the technical idea of ​​the present invention. It will be obvious to those skilled in the art to which the present invention pertains. [Explanation of symbols]

[0120] 100 Mask Frame 200 division mask 201 Page 1 202 2nd page 300 Deposition substrate 410 First photoresist pattern 411 First deposition pattern 412 Auxiliary Pattern 420 Second photoresist pattern 431 First Opening 432 Second Opening 451 First groove 452 2nd groove

Claims

1. preparing a divided mask substrate; forming a first photoresist pattern on one surface of the divided mask substrate, the first photoresist pattern including a first deposition pattern defining a first opening and an auxiliary pattern disposed inside the first opening; forming a second photoresist pattern defining a second opening on the other surface of the divided mask substrate; half-etching the one surface of the divided mask substrate; Applying a resin onto the one surface of the half-etched divided mask substrate; half-etching the other surface of the divided mask substrate; removing the resin, the first photoresist pattern including the auxiliary pattern, and the divided mask substrate inside the first opening; The auxiliary pattern overlaps with the second opening.

2. The method for manufacturing a mask assembly according to claim 1 , wherein a center of the auxiliary pattern coincides with a center of the first opening.

3. After half-etching the other surface of the divided mask substrate, 2. The method of claim 1, further comprising removing the second photoresist pattern.

4. 2. The method of claim 1, wherein the first photoresist pattern has an area larger than an area of ​​the second photoresist pattern.

5. 2. The method of claim 1, wherein the first photoresist pattern further comprises at least one connection portion connecting the first deposition pattern and the auxiliary pattern.

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