Evaporation mask, method for manufacturing a display device using the same, and display device

Abstract

To provide a deposition mask, method of manufacturing a display device using the deposition mask, and display device.SOLUTION: A deposition mask is provided, comprising: a main frame defining a first opening; multiple ribs extending away from a side of the main frame, the ribs being apart from each other and defining second openings; and bridges connecting the ribs together across the second openings. The bridges and the ribs form the same top surface, and a thickness of each of the bridges is less than a thickness of each of the ribs.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to a deposition mask, a method for manufacturing a display device using the deposition mask, and a display device. [Background technology]

[0002] In recent years, the uses of display devices have become more diverse, and the thickness and weight of display devices have become thinner and lighter, widening the scope of their use.

[0003] As displays are used in a variety of applications, they are designed to have different shapes and an increasing number of functions are combined with or associated with the displays. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Korean Patent No. 10-0982021 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the embodiments of the present invention is to provide a deposition mask, a method for manufacturing a display device using the deposition mask, and a display device. [Means for solving the problem]

[0006] According to one embodiment of the present invention, there is provided a deposition mask including: a main frame defining a first opening; a plurality of ribs extending outward from one side of the main frame in a plan view and spaced apart from each other to define a second opening; and a plurality of bridges connecting the plurality of ribs across the second opening, wherein the plurality of bridges and the plurality of ribs have the same upper surface, and a thickness of each of the plurality of bridges is thinner than a thickness of each of the ribs.

[0007] In the present embodiment, the shape of a cross section perpendicular to the longitudinal direction of each of the plurality of bridges may be an inverted triangle.

[0008] In this embodiment, in each of the multiple bridges, the width of the bridge along a direction perpendicular to the longitudinal direction of the bridge is smaller than the thickness of the bridge, and the difference between the thickness of the rib and the thickness of the bridge may be 0.5 times or more the width of the bridge.

[0009] In this embodiment, the area of ​​the main frame adjacent the second opening may have the same shape as the bridges.

[0010] According to another embodiment of the present invention, there is provided a display device comprising: a substrate; a first display region including first pixels provided on the substrate; and a second display region including second pixels provided on the substrate and having a different resolution from the first display region, the first pixels and the second pixels comprising a common electrode integrally formed therewith, the common electrode comprising a main common electrode corresponding to the first display region and a plurality of extensions extending from the main common electrode to the second display region and spaced apart from each other, each of the plurality of extensions comprising a first region between the second pixels that is thinner than a thickness of the main common electrode.

[0011] In the present embodiment, the common electrode may further include a second region at a connection portion between the main common electrode and the plurality of extensions, the second region being thinner than the thickness of the main common electrode.

[0012] In this embodiment, the first region may intersect a corresponding one of the extensions.

[0013] In the present embodiment, in the second display region, a transmissive portion is defined between the plurality of extension portions, and the common electrode may not be provided in the transmissive portion.

[0014] In the present embodiment, the resolution of the second display area may be lower than the resolution of the first display area.

[0015] In this embodiment, the display device may further include a component that is disposed at a position overlapping the second display area and detects an external signal.

[0016] In this embodiment, each of the first pixel and the second pixel includes a thin film transistor and an organic electroluminescent element electrically connected to the thin film transistor, and a blocking layer may be further provided between the thin film transistor and the substrate in the second display region.

[0017] In this embodiment, a first buffer layer and a second buffer layer may further be provided on the substrate, and the blocking layer may be disposed between the first buffer layer and the second buffer layer.

[0018] In this embodiment, the active layer of the thin film transistor may include a silicon material, the first buffer layer may include silicon nitride, and the second buffer layer may include silicon oxide.

[0019] In the present embodiment, the display device further includes a planarization layer provided between the thin film transistor and the organic electroluminescent device, and a pixel defining film provided on the planarization layer to cover an edge of a pixel electrode of the organic electroluminescent device and define a light emitting region, and the planarization layer and the pixel defining film may not be provided at a position overlapping the transmissive portion.

[0020] In the present embodiment, the number of the second pixels provided in the second display region may be smaller than the number of the first pixels provided in the first display region per unit area.

[0021] According to yet another embodiment of the present invention, a method for manufacturing a display device is disclosed, the method including: bringing a substrate and a deposition mask into close contact with each other, and forming an integrated common electrode on the substrate through the deposition mask, the deposition mask including: a main frame defining a first opening; a plurality of ribs protruding outward from one side of the main frame in a plane and spaced apart from each other to define a second opening; and a plurality of bridges crossing the second opening, connecting the plurality of ribs to fix positions of the plurality of ribs, and having a thickness thinner than that of the ribs, the common electrode including a main common electrode deposited through the first opening, and a plurality of extensions deposited through second openings between the plurality of ribs, the plurality of extensions being formed to include first regions having a thickness thinner than that of the main common electrode at positions where the bridges are disposed. Effect of the Invention

[0022] According to an embodiment of the present invention, a display device with an expanded display area can be realized so that an image can be displayed even in the area where components are arranged. In addition, a common electrode can be formed over the entire main display area and the area where components are arranged by a single deposition. [Brief description of the drawings]

[0023] [Figure 1] 1 is a perspective view illustrating an example of a display device according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view showing an example of a cross section taken along line AA' and line BB' in FIG. 1. [Diagram 3] 2 is a perspective view showing a schematic diagram of a part of a manufacturing process of the display device shown in FIG. 1. [Figure 4] FIG. 4 is a plan view illustrating a schematic view of a part of the deposition mask of FIG. [Diagram 5] 3 is a cross-sectional view illustrating an example of a manufacturing apparatus used in the manufacturing process of the display device of FIG. 2. [Figure 6] 5 is a cross-sectional view showing an example of a cross section taken along line II-II' of FIG. 4. [Figure 7] FIG. 2 is a plan view illustrating the display device of FIG. [Figure 8] 8 is a plan view illustrating a schematic view of a portion of a common electrode of the display device of FIG. 7. [Figure 9] 9 is a cross-sectional view showing an example of a cross section taken along line IV-IV' of FIG. 8. FIG. [Figure 10] 6 is a cross-sectional view showing an example of a cross section taken along line VI-VI' of FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The present invention can be modified in various ways and has various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention, as well as methods for achieving them, will become clear when referring to the embodiments described in detail below with the drawings. However, the present invention is not limited to the embodiments disclosed below, and can be realized in various forms.

[0025] In the following embodiments, the terms "first", "second" and the like are not used in a limiting sense but are used for the purpose of distinguishing one component from another component.

[0026] In the following embodiments, singular expressions include plural expressions unless otherwise clearly indicated in the context.

[0027] In the following embodiments, terms such as "comprise" or "have" mean the presence of features or components described in the specification, and do not preclude the possibility that one or more other features or components may be added.

[0028] In the following embodiments, when a part such as a film, region, or component is said to be on another part, this includes not only when it is directly on top of the other part, but also when there is another film, region, component, etc. interposed between them.

[0029] In the drawings, the size of components may be exaggerated or reduced for convenience of explanation. For example, the size and thickness of each component shown in the drawings are arbitrarily depicted for convenience of explanation, and the present invention is not necessarily limited to what is shown in the drawings.

[0030] When an embodiment can be realized in different forms, the order of certain steps may be different than that stated. For example, two steps stated in succession may be performed substantially simultaneously or may be performed in the reverse order from that stated.

[0031] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which the same or corresponding elements are designated by the same reference numerals.

[0032] FIG. 1 is a perspective view illustrating an example of a display device according to an embodiment of the present invention.

[0033] 1, a display area DA of a display device 1 includes a first display area DA1 and a second display area DA2. The first display area DA1 is a main display area that displays a main image using light emitted from a plurality of first pixels Pm.

[0034] The second display area DA2 is an area in which sensors that use optical signals and acoustic signals are arranged under the substrate 100, and the second display area DA2 is provided with a transmissive portion TA so that the sensors can receive external optical signals and / or acoustic signals and output the signals from the sensors to the outside of the display device 1. A plurality of second pixels Pa are also arranged in the second display area DA2. The second display area DA2 also provides an image using light emitted from the second pixels Pa. However, since the transmissive portion TA is arranged in the second display area DA2, the resolution is lower than that of the image provided in the first display area DA1. In other words, per the same unit area, the number of second pixels Pa arranged in the second display area DA2 is smaller than the number of first pixels Pm arranged in the first display area DA1.

[0035] In the following, an organic electroluminescent device (OLED) display device will be described as an example of a display device 1 according to an embodiment of the present invention, but various types of display devices, such as an inorganic EL display device or a quantum dot emitting display device, can be used as a display device according to an embodiment of the present invention.

[0036] FIG. 2 is a cross-sectional view that illustrates an example of a cross section taken along line AA' and line BB' in FIG.

[0037] As shown in FIG. 2, the first pixel Pm and the second pixel Pa have an organic electroluminescent element OLED and a thin film transistor TFT of basically the same structure, and the only difference is the number of elements arranged per unit area in the first display area DA1 and the second display area DA2.

[0038] First, the display device 1 includes a substrate 100 including a first display area DA1 and a second display area DA2, and a component 300 disposed at a position overlapping the second display area DA2.

[0039] The component 300 may be an electronic element that uses light or sound. For example, the component 300 may be a sensor that receives and uses light, such as an infrared sensor, a sensor that outputs and senses light or sound to measure distance or recognize fingerprints, a small lamp that outputs light, a speaker that outputs sound, an image sensor, or the like. In the case of an electronic element that uses light, it goes without saying that light in various wavelength bands, such as visible light, infrared light, and ultraviolet light, can be used. There may be a plurality of components 300 arranged in the second display area DA2. For example, a light emitting element and a light receiving element may be provided together in one second display area DA2 as the component 300. Also, a light emitting unit and a light receiving unit may be provided simultaneously in one component 300.

[0040] The substrate 100 includes glass or a polymer resin. The polymer resin may include polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose acetate propionate, and the like. The substrate 100 including the polymer resin has flexibility, rotation, or bending properties. The substrate 100 may have a multi-layer structure including a layer including the above-mentioned polymer resin and an inorganic layer (not shown).

[0041] A buffer layer 111 is provided on the substrate 100. The buffer layer 111 can reduce or block the penetration of foreign matter, moisture, or outside air from the bottom of the substrate 100, and can provide a flat surface on the substrate 100.

[0042] The buffer layer 111 includes an inorganic material such as an oxide or a nitride, an organic material, or an organic-inorganic composite material, and is formed in a single layer or multilayer structure of an inorganic material and an organic material. As an example, the buffer layer 111 may have a structure in which a first buffer layer 111a and a second buffer layer 111b are stacked, and in this case, the first buffer layer 111a and the second buffer layer 111b may be formed of different materials. For example, the first buffer layer 111a includes silicon nitride, for example, SiN x The second buffer layer 111b may contain silicon oxide, for example, SiO x may also contain

[0043] In this way, when the first buffer layer 111a contains silicon nitride, hydrogen may be contained during the formation of the silicon nitride, which improves the carrier mobility of the active layer 1130 formed on the buffer layer 111, and improves the electrical characteristics of the thin film transistor TFT. The active layer 1130 may be formed containing a silicon material, in which case the interface junction characteristics between the active layer 1130 containing silicon and the second buffer layer 111b containing silicon oxide are improved, and the electrical characteristics of the thin film transistor TFT are improved.

[0044] A thin film transistor TFT including an active layer 1130, a gate electrode G, a source electrode S, and a drain electrode D is provided on the buffer layer 111. In the following, a top-gate type thin film transistor TFT in which the gate electrode G is disposed on the active layer 1130 will be described, but the thin film transistor TFT may be a bottom-gate type in which the gate electrode G is located below the active layer 1130.

[0045] The active layer 1130 on the buffer layer 111 includes, for example, polysilicon. The active layer 1130 includes a channel region overlapping with the gate electrode G, and a source region and a drain region disposed on both sides of the channel region and doped with a higher concentration of impurities than the channel region. Here, the impurities are N-type impurities or P-type impurities. In other embodiments, the active layer 1130 may include amorphous silicon or an organic semiconductor material. In still other embodiments, the active layer 1130 may include an oxide semiconductor.

[0046] A gate electrode G is disposed on the active layer 1130 with a first gate insulating layer 112 sandwiched therebetween. The gate electrode G includes molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), etc., and is formed as a single layer or multiple layers.

[0047] The first gate insulating layer 112 is made of silicon oxide (SiO 2 ), silicon nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), tantalum oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ), Zinc oxide (ZnO 2 ) etc.

[0048] A second gate insulating layer 113 is provided so as to cover the gate electrode G. The second gate insulating layer 113 is made of silicon oxide (SiO 2 ), silicon nitride (SiNx ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), tantalum oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ), Zinc oxide (ZnO 2 ) etc.

[0049] A source electrode S and a drain electrode D are disposed on the interlayer insulating layer 115. The source electrode S and the drain electrode D include conductive materials such as molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), etc., and are formed of a multilayer or single layer including the above materials.

[0050] A planarization layer 117 is provided on the source electrode S and the drain electrode D, and an organic electroluminescence element OLED is provided on the planarization layer 117. The organic electroluminescence element OLED is electrically connected to the thin film transistor TFT. As an example, the organic electroluminescence element OLED may be electrically connected to the drain electrode D.

[0051] The planarization layer 117 has a flat upper surface so that the pixel electrode 210 can be formed flat. The planarization layer 117 is formed of a single layer or multiple layers of a film made of an organic material. The planarization layer 117 includes general-purpose polymers such as benzocyclobutene (BCB), polyimide, hexamethyldisiloxane (HMDSO), polymethylmethacrylate (PMMA), and polystyrene (PS), polymer derivatives containing phenols, acrylic polymers, imide polymers, aryl ether polymers, amide polymers, fluorine polymers, p-xylene polymers, vinyl alcohol polymers, and mixtures thereof. The planarization layer 117 may include an inorganic material. The planarization layer 117 may include silicon oxide (SiO 2 ), silicon nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2), tantalum oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ), Zinc oxide (ZnO 2 ) etc. If the planarization layer 117 is made of an inorganic material, CMP (chemical mechanical polishing) may be performed in some cases. The planarization layer 117 may also include both organic and inorganic materials.

[0052] The pixel electrode 210 is a (semi)transparent electrode or a reflective electrode. In some embodiments, the pixel electrode 210 includes a reflective film made of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a compound thereof, and a transparent or semitransparent electrode layer formed on the reflective film. The transparent or semitransparent electrode layer may be made of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In 2 O 3 In some embodiments, the pixel electrode 210 may have a stacked structure in which ITO / Ag / ITO are stacked.

[0053] A pixel definition film 119 is provided on the planarization layer 117. The pixel definition film 119 defines a light-emitting region by having an opening corresponding to a pixel, i.e., an opening that exposes at least a central portion of the pixel electrode 210. The pixel definition film 119 also increases the distance between the edge of the pixel electrode 210 and the common electrode 230, thereby preventing arcing or the like from occurring between them. The pixel definition film 119 is formed of an organic material such as polyimide or hexamethyldisiloxane (HMDSO).

[0054] The intermediate layer 220 includes a low molecular weight or high molecular weight material. When the intermediate layer 220 includes a low molecular weight material, the intermediate layer 220 has a structure in which a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), an electron injection layer (EIL), etc. are laminated in a single or composite structure, and includes various organic materials such as copper phthalocyanine (CuPc), N,N-di-(naphthalene-1-yl)-N,N'-diphenyl-benzidine (NPB), tris-8-hydroxyquinoline aluminum (Alq3), etc. Such a layer may be formed by a vacuum deposition method.

[0055] When the intermediate layer 220 includes a polymer material, the intermediate layer 220 has a structure including a hole transport layer (HTL) and an emission layer (EML). In this case, the hole transport layer includes poly(3,4-ethylenedihydroxythiophene) (PEDOT), and the emission layer includes a polymer material such as polyphenylenevinylene (PPV) and polyfluorene. The structure of the intermediate layer 220 is not limited to the above, and may have various structures. For example, at least one of the layers constituting the intermediate layer 220 may be integrally formed across the multiple pixel electrodes 210. Alternatively, the intermediate layer 220 may include layers patterned to correspond to each of the multiple pixel electrodes 210.

[0056] The common electrode 230 is a translucent electrode or a reflective electrode. In some embodiments, the common electrode 230 is a transparent or semi-transparent electrode and is formed of a low work function metal thin film, including Li, Ca, LiF / Ca, LiF / Al, Al, Ag, Mg, and their combinations. The common electrode 230 is disposed across the first display area DA1 and the second display area DA2, and is disposed on the intermediate layer 220 and the pixel defining film 119.

[0057] The transmissive portion TA of the second display area DA2 is an area through which optical signals and / or acoustic signals emitted from the component 300 pass, and for precise signal transmission therethrough, the common electrode 230 is not formed in the transmissive portion TA. When the common electrode 230 is not formed in the transmissive portion TA, the transmittance is improved by about 1.5 times or more compared to when the common electrode 230 is formed. A manufacturing process for manufacturing the common electrode 230 having such a characteristic structure will be described later. In addition, the planarization layer 117 and the pixel defining film 119 may be removed from the transmissive portion TA in order to improve the transmittance.

[0058] In the second display area DA2, a blocking layer BSM is provided between the substrate 100 and the thin film transistor TFT at a position overlapping with the second pixel Pa. The blocking layer BSM prevents the thin film transistor TFT from being affected by optical signals and audio signals of the adjacent component 300. As an example, the blocking layer BSM may be located between the first buffer layer 111a and the second buffer layer 111b.

[0059] Although not shown, a thin-film sealing layer in which at least one inorganic sealing layer and at least one organic sealing layer are laminated is formed on the common electrode 230. The inorganic sealing layer includes one or more inorganic insulators selected from aluminum oxide, titanium oxide, tantalum oxide, hafnium oxide, zinc oxide, silicon oxide, silicon nitride, and silicon oxynitride, and the organic sealing layer includes polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, acrylic resin (e.g., polymethyl methacrylate, polyacrylic acid, etc.), or any combination thereof.

[0060] FIG. 3 is an oblique view that illustrates a part of the manufacturing process of the display device of FIG. 1, FIG. 4 is a plan view that illustrates a part of the deposition mask of FIG. 3, FIG. 5 is a cross-sectional view that illustrates an example of a manufacturing apparatus used in the manufacturing process of the display device of FIG. 2, and FIG. 6 is a cross-sectional view that illustrates an example of the II-II' cross section of FIG. 4.

[0061] 3 shows a method for forming the common electrode 230 (FIG. 7) on the substrate 100. Specifically, after a deposition mask 10 and the substrate 100 are closely attached to each other, a material for forming the common electrode 230 (FIG. 7) is deposited on the substrate 100 through the deposition mask 10. Meanwhile, the common electrode 230 (FIG. 7) is formed across the first display area DA1 and the second display area DA2 by a single deposition process, and for this purpose, the deposition mask 10 includes a first opening 12 and a plurality of ribs 13 corresponding to the first display area DA1.

[0062] The first opening 12 is defined by a main frame 11 of the deposition mask 10, and the multiple ribs 13 protrude outward from one side of the main frame 11 on a plane so as to correspond to the second display area DA2.

[0063] The ribs 13 are spaced apart from one another, and second openings 15 are defined between the ribs 13, as shown in Fig. 4. The ribs 13 are positioned to correspond to the transmissive portion TA (Fig. 6), and as a result, the common electrode 230 (Fig. 7) is not deposited on the transmissive portion TA (Fig. 6).

[0064] Meanwhile, the second opening 15 is provided at a position overlapping with the second pixels Pa, and the common electrode 230 (FIG. 7) is deposited at a position corresponding to the second pixels Pa. At this time, the width of the second opening 15 is formed wider than the width of the second pixels Pa, so that the common electrode 230 (FIG. 7) deposited through the second opening 15 is formed to cover the second pixels Pa. Here, the width of the second pixel Pa means the width of the opening of the pixel defining film 119 (FIG. 2) for defining the light emitting region. Therefore, even if a minute alignment error occurs between the deposition mask 10 and the substrate 100 during the process of forming the common electrode 230 (FIG. 7), it is possible to prevent the common electrode 230 (FIG. 7) from being defectively formed.

[0065] Meanwhile, the ribs 13 are connected to each other by a bridge 14. As an example, the bridge 14 crosses the second opening 15 and is located between the formation regions of the second pixels Pa. Here, the bridge 14 crossing the second opening 15 does not only mean crossing the second opening 15 in the shortest distance, but also includes the bridge 14 crossing the second opening 15 in a straight line at an angle according to the positions of the second pixels Pa, as shown in FIG. 4. The bridge 14 fixes the positions of the ribs 13 formed long on one side to each other, thereby enabling the common electrode 230 (FIG. 7) to be formed at an accurate position in the second display region DA2.

[0066] The common electrode 230 (FIG. 7) is formed using the deposition mask 10 by using the manufacturing apparatus 400 shown in FIG. The manufacturing apparatus 400 includes a chamber 410, a mask assembly 420, a first supporting unit 430, a second supporting unit 440, a deposition source 450, a magnetic force generating unit 460, an image unit 470, and a pressure adjusting unit 480.

[0067] The chamber 410 may be formed to have a space therein, and a portion of the chamber 410 may be opened. In this case, a gate valve 411 may be disposed in the opened portion of the chamber 410 so as to be capable of opening and closing. In addition, the pressure adjusting unit 480 is connected to the chamber 410 and adjusts the pressure inside the chamber 410. In this case, the pressure adjusting unit 480 includes a connecting pipe 481 connected to the chamber 410 and a pump 482 disposed in the connecting pipe 481.

[0068] The mask assembly 420 includes a mask sheet 422 and a mask frame 421 coupled to the mask sheet 422. The mask sheet 422 includes the above-described deposition mask 10. As an example, the mask sheet 422 may include a plurality of deposition masks 10. The mask sheet 422 is fixed to the mask frame 421 in a tensioned state.

[0069] The substrate 100 is placed on the first support part 430. The first support part 430 can adjust the position of the substrate 100. For example, the first support part 430 includes a UVW stage. The mask assembly 420 is placed on the second support part 440. The second support part 440 can adjust the position of the mask assembly 420, similar to the first support part 430.

[0070] After the deposition material is accommodated in the deposition source 450, the deposition source 450 vaporizes or sublimes the deposition material and supplies the deposition material to the chamber 410. At this time, the deposition source 450 may include a heater therein, and the deposition material inside the deposition source 450 is heated by the operation of the heater, thereby melting or sublimating the deposition material.

[0071] The imaging unit 470 is disposed in the chamber 410 and captures the positions of the mask assembly 420 and the substrate 100. At this time, the imaging unit 470 captures at least one alignment mark of the mask assembly 420 and the substrate 100.

[0072] The magnetic force generator 460 is disposed in the chamber 410 and brings the substrate 100 and the mask assembly 420 into close contact with each other. The magnetic force generator 460 includes an electromagnet or a permanent magnet that generates a magnetic force. Meanwhile, as described above, the deposition mask 10 includes the bridge 14 that fixes the positions of the ribs 13 formed long on one side, thereby preventing the position of the ribs 13 from shifting when the substrate 100 and the mask assembly 420 are brought into close contact with each other. As a result, the common electrode 230 (FIG. 7) is deposited at an accurate position in the second display area DA2.

[0073] In the second display area DA2, the common electrode 230 (FIG. 7) is deposited through the second openings 15 between the ribs 13. However, since the bridge 14 is positioned to cross the second openings 15 as described above, it is necessary to prevent the common electrode 230 (FIG. 7) deposited through the second openings 15 from being broken by the bridge 14. For this reason, as shown in FIG. 6, the bridge 14 and the rib 13 have the same upper surface, and the thickness of the bridge 14 is thinner than the thickness of the rib 13. That is, since the lower surface of the bridge 14 is separated from the deposition surface on which the common electrode 230 is deposited, the common electrode 230 is also deposited under the bridge 14, and the common electrode 230 (FIG. 7) can be continuously formed in the second display area DA2 without being broken by the bridge 14.

[0074] In addition, since the rib 13 has a shape protruding from the main frame 11 of the deposition mask 10, the main frame 11 must prevent the common electrode 230 (FIG. 7) from being disconnected in the first display area DA1 and the second display area DA2. For this reason, in the main frame 11, the area P adjacent to the second opening 15 has the same shape as the bridge 14 shown in FIG. 6. That is, in the area P, the main frame 11 has a thickness smaller than the surrounding area, and the II-II' and III-III' cross sections in FIG. 4 have the same shape as shown in FIG. 6. As a result, when the common electrode 230 (FIG. 7) is deposited using the deposition mask 10, it is possible to prevent the common electrode 230 (FIG. 7) from being separated in the first display area DA1 and the second display area DA2.

[0075] FIG. 7 is a plan view that shows a schematic representation of the display device of FIG. 1, FIG. 8 is a plan view that shows a schematic representation of a portion of the common electrode of the display device of FIG. 7, and FIG. 9 is a cross-sectional view that shows a schematic representation of an example of the IV-IV' cross section of FIG. 8.

[0076] First, as shown in FIG. 7, the display area DA includes a first display area DA1 and a second display area DA2 having different resolutions, and the common electrode 230 includes a main common electrode 230a located in the first display area DA1 and a plurality of extension portions 230b located in the second display area DA2.

[0077] The common electrode 230 is formed by a single deposition process using the above-mentioned deposition mask 10 (FIG. 3), so that the main common electrode 230a and the multiple extensions 230b are integrally formed. Therefore, the first pixel Pm and the second pixel Pa include one common electrode 230 that is integrally formed.

[0078] In the first display area DA1, a plurality of first pixels Pm are densely arranged, and the main common electrode 230a is integrally formed corresponding to the plurality of first pixels Pm.

[0079] In the second display area DA2, the second pixels Pa are arranged coarser than the first pixels Pm. Therefore, the resolution of the second display area DA2 is lower than the resolution of the first display area DA1. The multiple extensions 230b extend from the main common electrode 230a and correspond to the second pixels Pa, respectively.

[0080] 7 shows the plurality of extensions 230b having a zigzag shape, the shape of the extensions 230b may be variously changed depending on the arrangement of the second pixels Pa. For example, the plurality of extensions 230b may be formed in a straight line or in an oblique line depending on the arrangement of the second pixels Pa. The plurality of extensions 230b are spaced apart from each other in a direction perpendicular to the extending direction to form a transmission portion TA.

[0081] The extensions 230b each cover a plurality of second pixels Pa, but the width of the extensions 230b is wider than the width of the second pixels Pa. Here, the width of the second pixels Pa refers to the width of an opening of the pixel defining film 119 (FIG. 2) for defining a light emitting region. The extensions 230b also include a first region G between the plurality of second pixels Pa that is thinner than the thickness of the main common electrode 230a. The first region G1 has a concave shape with a lower upper surface position compared to the surrounding area. The first region G is formed at a position where the bridge 14 (FIG. 4) described above was located, and has the same pattern as the bridge 14 (FIG. 4). That is, the first region G may be provided to cross the extensions 230b.

[0082] As described above, the region P (FIG. 4) of the main frame adjacent to the second opening 15 (FIG. 4) has the same shape as the bridge 14 (FIG. 4), so the common electrode 230 may further include a second region Q at the connection portion between the main common electrode 230a and the extension 230b, the second region Q being lower in height than the surrounding common electrode 230. That is, the IV-IV' and V-V' cross sections of FIG. 8 have the same shape as shown in FIG. 9.

[0083] FIG. 10 is a cross-sectional view that illustrates an example of a cross section taken along line VI-VI' of FIG.

[0084] 10 shows a cross-sectional shape perpendicular to the longitudinal direction of the bridge 14. As described above, since the lower surface of the bridge 14 is separated from the deposition surface, the common electrode 230 (FIG. 7) is also deposited on the lower portion of the bridge 14. Meanwhile, since the deposition material is incident obliquely during deposition of the common electrode 230 (FIG. 7), the vertical cross-sectional shape of the bridge 14 may be an inverted triangle in order to improve the deposition efficiency on the lower portion of the bridge 14. However, the present invention is not limited thereto, and the bridge 14 may have various shapes.

[0085] In addition, in order to improve the efficiency of deposition of the common electrode 230 (FIG. 2) on the lower part of the bridge 14, the thickness T 2 is larger than the width W of the bridge 14 and the thickness T of the rib 13 1 and the thickness T of bridge 14 2The difference between them may be 0.5 times or more the width W of the bridge 14.

[0086] Although the present invention has been described with reference to the embodiment shown in the drawings, this is merely an example, and those skilled in the art will understand that various modifications and variations of the embodiment are possible therefrom. Therefore, the true technical scope of the present invention should be determined by the technical ideas of the claims. [Industrial Applicability]

[0087] The present invention is applicable, for example, to display-related technical fields. [Explanation of symbols]

[0088] 1 Display device 100 Substrates 111 Buffer layer 111a First buffer layer 111b Second buffer layer 112 First gate insulating layer 113 Second gate insulating layer 115 Interlayer insulation layer 117 Planarization layer 119 Pixel-defined membrane 210 Pixel electrode 220 Middle Class 230 Common electrode 300 Components 1130 Active layer BSM Blocking Layer D drain electrode DA display area DA1 1st display area DA2 2nd display area G gate electrode OLED Organic Electroluminescent Device Pa 2nd pixel Pm 1st pixel S source electrode TA transparent part TFT Thin Film Transistor

Claims

1. a main frame defining a first opening; a plurality of ribs extending outwardly from one side of the main frame in a plan view and spaced apart from one another to define a second opening; a plurality of bridges connecting the plurality of ribs across the second opening; a deposition mask, wherein the plurality of bridges and the plurality of ribs form a same upper surface, and a thickness of each of the plurality of bridges is thinner than a thickness of each of the ribs.

2. 2. The deposition mask according to claim 1, wherein each of the bridges has a cross section perpendicular to a longitudinal direction of the bridge that has an inverted triangular shape.

3. 2. The deposition mask according to claim 1, wherein, in each of the bridges, a width of the bridge along a direction perpendicular to a longitudinal direction of the bridge is smaller than a thickness of the bridge, and a difference between a thickness of the rib and a thickness of the bridge is 0.5 times or more the width of the bridge.

4. The deposition mask of claim 1 , wherein a region of the main frame adjacent to the second opening has the same shape as the plurality of bridges.

5. A substrate; a first display region including a first pixel provided on the substrate; a second display area including second pixels disposed on the substrate and having a different resolution than the first display area; The first pixel and the second pixel include a common electrode formed integrally with each other, the common electrode includes a main common electrode corresponding to the first display area, and a plurality of extensions extending from the main common electrode to the second display area and spaced apart from each other; The display device, wherein each of the plurality of extensions includes a first region between the second pixels that is thinner than a thickness of the main common electrode.

6. The display device of claim 5, wherein the common electrode further comprises a second region, the second region being thinner than the thickness of the main common electrode, at a connection portion between the main common electrode and the plurality of extensions.

7. The display device of claim 5 , wherein the first region crosses a corresponding one of the extensions.

8. In the second display region, a transparent portion is defined between the plurality of extension portions, The display device according to claim 5 , wherein the common electrode is not provided in the transmissive portion.

9. The display device according to claim 8 , wherein the resolution of the second display area is lower than the resolution of the first display area.

10. The display device of claim 5, further comprising a component disposed at a position overlapping the second display area and configured to sense an external signal.

11. Each of the first pixel and the second pixel includes a thin film transistor and an organic electroluminescent device electrically connected to the thin film transistor, The display device of claim 10, further comprising a blocking layer between the thin film transistor and the substrate in the second display area.

12. A first buffer layer and a second buffer layer are further provided on the substrate, The display device of claim 11, wherein the blocking layer is disposed between the first buffer layer and the second buffer layer.

13. the active layer of the thin film transistor comprises a silicon material; The display device of claim 12, wherein the first buffer layer comprises silicon nitride and the second buffer layer comprises silicon oxide.

14. The second display region includes a transparent portion between the plurality of extension portions, The common electrode is not provided in the transmissive portion, a planarization layer provided between the thin film transistor and the organic electroluminescent device; and a pixel definition layer provided on the planarization layer, covering an edge of a pixel electrode of the organic electroluminescent device to define a light-emitting region, The display device of claim 11, wherein the planarization layer and the pixel defining layer are not provided at a position overlapping the transmissive portion.

15. 6. The display device according to claim 5, wherein the number of the second pixels provided in the second display region is smaller than the number of the first pixels provided in the first display region per unit area.

16. The substrate and the deposition mask are brought into close contact with each other, forming an integral common electrode on the substrate through the deposition mask; The deposition mask is a main frame defining a first opening; a plurality of ribs projecting outwardly from one side of the main frame in a plan view and spaced apart from one another to define a second opening; a plurality of bridges across the second opening, connecting the plurality of ribs to fix positions of the plurality of ribs, the bridges having a thickness less than that of the ribs; the common electrode includes a main common electrode deposited through the first opening and a plurality of extensions deposited through second openings between the plurality of ribs; 4. A method for manufacturing a display device, comprising the steps of: forming a first region having a thickness smaller than that of the main common electrode at a position where the bridge is disposed;

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