Metal plate and deposition mask comprising same

Abstract

A metal plate according to an embodiment is a metal plate having a length (L) of 900 mm to 1100 mm, a width (W) of 290 mm to 300 mm, and a thickness (T) of 15 [mu] m to 100 [mu] m, in which the metal plate comprises an invar alloy, the thickness of the metal plate is adjusted to a test thickness (X) of 3 [mu] m to 10 [mu] m to form a unit metal plate having a unit size of L * W * X, the number of inclusions per unit size of the unit metal plate is 10 or less, and the number of inclusions per unit size of the unit metal plate is 10 or less. And the size of the inclusions exceeds the test thickness.

Description

Technical Field

[0001] Embodiments relate to deposition masks for OLED pixel deposition. Background Art

[0002] Display devices are applied to various devices. For example, display devices are applied to small devices such as smart phones or tablet computers. Alternatively, display devices are applied to large devices such as televisions, monitors or public displays (PDs). Recently, the demand for ultra-high definition (UHD) with a resolution of 500 PPI (pixels per inch) or higher is increasing. Therefore, display devices with high resolution are being applied to small devices and large devices.

[0003] Display devices are classified into LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diode) according to a driving method.

[0004] LCD is a display device driven by liquid crystal, while OLED is a display device driven by organic matter.

[0005] OLED can achieve extremely high contrast, has a response speed 1000 times faster than LCD, and has excellent viewing angle. Therefore, OLED has attracted attention as a display device that can replace LCD.

[0006] The OLED includes a light-emitting layer. The light-emitting layer includes an organic material. The organic material is deposited on a substrate through a deposition mask. The deposition mask may include an opening mask (OM) or a fine metal mask (FMM). A deposition pattern corresponding to the pattern formed in the deposition mask is formed on the substrate. Therefore, the deposition pattern can be used as a pixel.

[0007] An open mask is a thin plate that forms a deposition pattern only at specific locations when manufacturing OLEDs. During the display manufacturing process, after the backplane is completed, an open mask is used in the deposition process to form a light-emitting layer thereon. In other words, an open mask is a mask that does not have a coverage area within the range where the display operates in order to deposit the entire surface of the display. Therefore, an open mask is used when depositing a light-emitting layer having a light-emitting material of one color.

[0008] On the other hand, the fine metal mask is used to change the color of the sub-pixel of the light-emitting layer. Therefore, the fine metal mask includes ultra-fine holes. The process using the fine metal mask must perform several deposition stages. Therefore, the process requires precise alignment. Therefore, the process using the fine metal mask is more difficult than the process using the opening mask.

[0009] When the light-emitting layer of the OLED is deposited through an open mask, only one color light-emitting layer is formed. Therefore, a separate color filter (C / F) is required to achieve various colors. On the other hand, when a fine metal mask is used, an RGB light-emitting layer can be formed. Therefore, no separate color filter is required. In other words, the technology using a fine metal mask is more difficult. However, unlike the method using an open mask, the method using a fine metal mask is more light efficient because the method using a fine metal mask does not require a filter to block light.

[0010] Fine metal mask is usually made of Invar metal plate containing iron (Fe) and nickel (Ni). Through holes are formed on one surface and another surface of the metal plate, and the through holes penetrate one surface and another surface. The through holes are formed at positions corresponding to the pixel pattern. Therefore, red, green and blue organic materials can pass through the through holes of the metal plate and be deposited on the substrate. Therefore, a pixel pattern can be formed on the substrate.

[0011] The fine metal mask can be manufactured using a metal plate made of an iron (Fe)-nickel (Ni) alloy. For example, the deposition mask can be manufactured using Invar alloy.

[0012] The metal plate may include various impurities such as oxygen, iron element, and sulfur element in addition to iron and nickel. The impurities form crystals inside the metal plate. Therefore, the impurities may remain in the metal plate as inclusions.

[0013] If the size of the inclusion is large, the size of the through hole may be changed by the inclusion. Alternatively, adjacent through holes may be connected by the inclusion. Therefore, the deposition quality of the deposition mask may be reduced.

[0014] Therefore, there is a need for an inclusion testing method, a metal plate, and a deposition mask that can solve the above-mentioned problems. Summary of the invention

[0015] Technical issues

[0016] Embodiments provide a deposition mask that reduces defects in vias.

[0017] Embodiments provide deposition masks with improved through-hole uniformity.

[0018] Technical Solutions

[0019] The metal plate according to the embodiment is a metal plate having a length (L) of 900 mm to 1100 mm, a width (W) of 290 mm to 300 mm, and a thickness (T) of 15 μm to 100 μm, wherein the metal plate includes Invar alloy, and the thickness of the metal plate is adjusted to a test thickness (X) of 3 μm to 10 μm to form a unit metal plate having a unit size of L×W×X, the number of inclusions per unit size of the unit metal plate is 10 or less, and the size of the inclusions exceeds the test thickness.

[0020] Beneficial Effects

[0021] The metal plate according to the embodiment can control the number of inclusions, specifically, control the number of inclusions having a size greater than or equal to a set size in a unit metal plate of a unit size.

[0022] The metal plate controls the DPU (defect per unit) of the unit metal plate within a set range. Therefore, the defects of the through holes of the deposition mask manufactured by the unit metal plate are reduced. Therefore, the deposition mask has improved deposition quality and deposition reliability.

[0023] In addition, the normality and defects of the unit metal plate can be checked in advance before manufacturing the deposition mask. Therefore, the process of manufacturing the deposition mask with a defective unit metal plate can be prevented. Therefore, the process efficiency is improved.

[0024] In addition, the number of inclusions in the cell size sample whose size is greater than or equal to a set size can be controlled.

[0025] Therefore, the DPU (defects per unit) of the deposition mask is controlled within a set range. Therefore, defects of through holes are reduced. Therefore, the deposition mask improves deposition quality and deposition reliability.

[0026] In addition, after manufacturing the deposition mask, the deposition quality and deposition reliability of the deposition mask can be confirmed in advance by the size of DPU (defects per unit). Therefore, only the deposition mask with a small through-hole defect rate can be selectively selected. Therefore, the efficiency of the deposition process is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figures 1 to 10 It is a diagram for explaining a method of testing a metal plate according to an embodiment.

[0028] Fig.11 and Fig.12 Here are photos of experimental examples.

[0029] Fig.13 is a diagram illustrating a combination of a deposition mask and a frame according to an embodiment.

[0030] Fig.14is a cross-sectional view of an organic deposition apparatus including a deposition mask according to an embodiment.

[0031] Fig.15 is a diagram illustrating forming a deposition pattern on a deposition substrate through a through hole of a deposition mask according to an embodiment.

[0032] Fig.16 is a plan view of a deposition mask according to an embodiment.

[0033] Fig.17 is a diagram for explaining a defect of a through hole in a deposition mask according to an embodiment. DETAILED DESCRIPTION

[0034] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. However, the spirit and scope of the present invention are not limited to the parts of the described embodiments, and can be implemented in various other forms, and in the spirit and scope of the present invention, one or more of the elements of the embodiments can be selectively combined and reset. In addition, unless otherwise explicitly defined and described, the terms (including technical terms and scientific terms) used in the embodiments of the present invention can be interpreted as having the same meaning as that commonly understood by ordinary technicians in the field to which the present invention belongs, and terms such as those defined in commonly used dictionaries can be interpreted as having a meaning consistent with its meaning in the context of the relevant field.

[0035] In addition, the terms used in the embodiments of the present invention are used to describe the embodiments and are not intended to limit the present invention. In this specification, unless otherwise specified in a phrase, a singular form may also include a plural form, and when described as "at least one (or more) of A (and), B and C", the singular form may include at least one of all combinations that can be combined with A, B and C.

[0036] In addition, when describing the elements of the embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish an element from other elements, and the terms are not limited to the essence, order, or sequence of the elements.

[0037] In addition, when an element is described as being “connected,” “coupled” or “coupled” to another element, it may include not only the case where the element is directly “connected,” “coupled” or “coupled” to other elements, but also the case where the element is “connected,” “coupled” or “coupled” to the other elements through another element.

[0038] In addition, when described as being formed or arranged “on (above)” or “under (below)” each element, “on (above)” or “under (below)” may include not only the case where two elements are directly connected to each other, but also the case where one or more other elements are formed or arranged between the two elements.

[0039] In addition, when expressed as “upper (above)” or “lower (below)”, not only an upper direction but also a lower direction can be included based on one element.

[0040] The deposition mask described below is a fine metal mask (FMM) capable of depositing red, green and blue organic materials on a deposition substrate to form an RGB pixel pattern on the deposition substrate. In addition, the following description does not apply to an opening mask (OM).

[0041] In the following description, the first direction is the length direction of the metal plate or the deposition mask, and the second direction is the width direction of the metal plate or the deposition mask.

[0042] Reference Figures 1 to 5 , a metal plate and a testing method thereof according to an embodiment are described.

[0043] Metal plates and test methods thereof

[0044] The metal plate 10 according to the embodiment is a raw material for manufacturing the deposition mask according to the embodiment. That is, the deposition mask is formed by forming a plurality of through holes in the metal plate 10 .

[0045] Reference Figure 1 The testing method includes a first step of preparing a unit metal plate, a second step of arranging a supporting layer on one surface of the unit metal plate, a third step of controlling the thickness of the unit metal plate, a fourth step of checking the DPU (unit defect) of the unit metal plate, and a fifth step of determining the unit metal plate.

[0046] Reference Figures 1 to 3 , in a first step, a metal plate having a set size is prepared.

[0047] The metal plate 10 may include a first surface 1S and a second surface 2S opposite to the first surface 1S. In addition, the metal plate 10 has a set size.

[0048] The metal sheet 10 is provided in a state of being wound on a roll for roll-to-roll processing. In the first step, a unit metal sheet having a set size is cut from the roll.

[0049] The unit metal plate 10 has a set thickness. For example, the thickness (T) of the unit metal plate 10 may be 100 μm or less. Specifically, the thickness (T) of the unit metal plate 10 may be 15 μm to 100 μm, or 60 μm to 80 μm. The thickness (T) of the unit metal plate 10 is defined as the maximum distance from the first surface 1S to the second surface 2S.

[0050] In addition, the unit metal plate 10 has a set width (W) and length (L). For example, the length (L) of the unit metal plate 10 may be 900 mm to 1100 mm. The width (W) of the unit metal plate 10 may be 290 mm to 300 mm.

[0051] The metal plate includes an alloy. Specifically, the metal plate includes iron (Fe) and nickel (Ni). More specifically, the metal plate 10 contains iron (Fe), nickel (Ni), oxygen (O) and chromium (Cr). In addition, the metal plate may also include a small amount of at least one of the following elements: carbon (C), silicon (Si), sulfur (S), phosphorus (P), manganese (Mn), titanium (Ti), cobalt (Co), copper (Cu), silver (Ag), vanadium (V), niobium (Nb), indium (In) and antimony (Sb). As an example, the metal plate may include Invar alloy.

[0052] Invar is an alloy including iron and nickel. Invar is an alloy having a thermal expansion coefficient close to 0. Since the thermal expansion coefficient of Invar is very small, Invar is used for precision parts such as masks. Therefore, the deposition mask manufactured using the unit metal plate 10 has improved reliability. That is, deformation of the deposition mask is prevented. In addition, the life of the deposition mask is increased.

[0053] The metal plate may contain about 60wt% to about 65wt% of iron. In addition, the metal plate may contain about 35wt% to about 40wt% of nickel. Specifically, the metal plate contains about 63.5wt% to about 64.5wt% of iron and about 35.5wt% to about 36.5wt% of nickel. In addition, the metal plate may include about 1wt% or less of at least one of the following elements: carbon (C), silicon (Si), sulfur (S), phosphorus (P), manganese (Mn), titanium (Ti), cobalt (Co), copper (Cu), silver (Ag), vanadium (V), niobium (Nb), indium (In) and antimony (Sb).

[0054] The composition, content and wt% of the metal plate can be confirmed by sampling a sample. Specifically, a specific area is selected on the plane of the metal plate 10. Then, a sample corresponding to the thickness of the metal plate 10 is sampled. Then, the sample is dissolved in a strong acid, and the wt% of each component is confirmed. However, the embodiment is not limited thereto. The wt% of the composition can be confirmed by various methods that can confirm the composition of the metal plate.

[0055] The metal plate includes various elements in addition to iron and nickel. Therefore, the metal plate includes inclusions having various compositions, composition ratios, and sizes. Through holes are formed on the metal plate. If the number of inclusions is large or the size of the inclusions is large, defects may be generated in the through holes.

[0056] Therefore, the testing method of the metal plate confirms the size and number of inclusions in advance. Therefore, the metal plate capable of manufacturing the deposition mask can be selected in advance. Alternatively, after manufacturing the deposition mask, the defect rate of the through hole can be predicted according to the size and number of inclusions.

[0057] Reference Figure 1 and Figure 4 In the second step, the support layer 20 is disposed on the first surface 1S or the second surface 2S. For example, the support layer 20 is formed by rolling a roller on the first surface 1S. Thus, the support layer 20 is disposed on the first surface 1S.

[0058] The support layer 20 may include a resin material. In addition, the support layer 20 may be transparent. Specifically, the support layer 20 includes a light-transmitting material.

[0059] When the unit metal plate 10 is etched, the unit metal plate 10 is supported by the support layer 20. In addition, when light is irradiated to the unit metal plate, the support layer 20 may transmit the light. This will be described below.

[0060] Reference Figure 1 and Figure 5 In the third step, the thickness of the unit metal plate 10 is reduced to a set thickness. Specifically, the unit metal plate 10 is etched. Thus, the thickness of the unit metal plate 10 is controlled. Thus, the thickness of the unit metal plate 10 is changed to a test thickness (X).

[0061] For example, in the third step, the thickness of the unit metal plate 10 is changed from the initial thickness (T) to the test thickness (X). The test thickness (X) is the thickness of the unit metal plate 10 after etching.

[0062] For example, when the support layer 20 is provided on the first surface 1S, the second surface 2S is etched.

[0063] The thickness of the unit metal plate 10 may be controlled by various processes. For example, the unit metal plate 10 may be etched by a wet etching process. Specifically, the unit metal plate 10 may be etched with an acidic etchant.

[0064] The etchant may etch Invar metal. The etchant may include a ferric chloride solution. Alternatively, the etchant may include a solution in which at least one of perchloric acid, hydrochloric acid, sulfuric acid, formic acid, and acetic acid is mixed with the ferric chloride solution.

[0065] The unit metal plate 10 may be immersed in the etchant. Alternatively, the etchant may be sprayed on the second surface 2S. That is, the unit metal plate 10 may be etched by a dipping process or a spraying process.

[0066] Therefore, the thickness of the unit metal plate 10 is adjusted to a set thickness range. Specifically, the unit metal plate 10 is adjusted to a test thickness (X) of X μm. X may be 3 μm to 10 μm.

[0067] The metal plate may be rolled before etching the unit metal plate 10. The rolling process may be optionally performed.

[0068] For example, the unit metal plate 10 is subjected to a cold rolling process. Thus, the thickness of the unit metal plate 10 is formed to be about 30 μm or less. Subsequently, an etching process may be performed.

[0069] After the thickness of the unit metal plate 10 is measured, the unit size of the unit metal plate is defined by the thickness, length, and width of the unit metal plate 10. Specifically, the unit size is defined as length×width×test thickness (L×W×X). The unit size may correspond to the size of at least one deposition mask manufactured by the unit metal plate 10. That is, one or more deposition masks may be manufactured using the unit metal plate 10. The unit size is used when checking the DPU (defects per unit) of the metal plate described below.

[0070] Next, refer to Figures 6 to 9 In the fourth step, the size and number of inclusions of the unit metal plate 10 are checked. The inclusions include at least one of the following elements: carbon, oxygen, magnesium, aluminum, silicon, sulfur, calcium, and iron. That is, the fourth step checks DPU. DPU is the number of inclusions per unit size of the unit metal plate.

[0071] Reference Figure 6 , when X is adjusted to a range of 3 μm to 10 μm, most inclusions having a maximum size of X μm or less remain. For example, inclusions having a maximum size of X μm or less may include a first-first inclusion D1-1 and a first-second inclusion D1-2. The first-first inclusion D1-1 may remain. In addition, the first-second inclusion D1-2 may protrude from the second surface 2S.

[0072] In addition, second inclusions D2 having a maximum size exceeding X μm may be included. The second inclusions D2 protrude from the unit metal plate 10. Therefore, the second inclusions D2 protrude from the second surface 2S.

[0073] That is, the test thickness varies according to the size of the inclusions being measured. For example, when checking the number of inclusions exceeding 10 μm, the thickness (X) is controlled at 10 μm. Alternatively, when confirming the number of inclusions exceeding 3 μm, the thickness (X) is controlled to 3 μm.

[0074] That is, DPU (defects per unit) is defined as inclusions whose size exceeds the thickness of the unit metal sheet. That is, the size of the inclusion is greater than the thickness of the unit metal sheet.

[0075] In addition, the inclusion is related to the height (step height) of the small surface hole V1 of the deposition mask. Specifically, a small surface hole V1 is formed at one surface of the unit metal plate, and a large surface hole V2 is formed at the other surface. The small surface hole V1 and the large surface hole V2 are connected by a connecting portion CA to form a through hole. The height (step height) of the small surface hole V1 is the vertical distance from one surface of the metal plate to the connecting portion. The size of the inclusion is greater than or equal to the height (step height) of the small surface hole V1.

[0076] Reference Figure 7 , the inclusions protruding outward from the second surface 2S may extend outward from the unit metal plate 10. The inclusions form crevice corrosion with the unit metal plate 10. The first-first inclusion D1-1 and the second inclusion D2 extend outward from the unit metal plate 10 due to crevice corrosion.

[0077] Therefore, refer to Figure 8 , a surface hole is formed in the region where the first-first inclusion D1-1 and the second inclusion D2 come out. For example, the unit metal plate 10 includes a first surface hole H1 and a second surface hole H2. The first surface hole H1 is the region where the first-first inclusion D1-1 comes out. The second surface hole H2 is the region where the second inclusion D2 comes out.

[0078] Reference Fig. 9 , the light source 30 is disposed under the second surface 2S. Then, the light is irradiated to the second surface 2S. The light of the light source 30 may move from the second surface 2S to the first surface 1S.

[0079] The DPU (defects per unit) may be confirmed by light projected from the support layer 20 .

[0080] Specifically, light incident on the first surface hole H1 and the second surface hole H2 passes through the support layer 20. In addition, light incident on a region other than the surface holes of the unit metal plate 10 does not pass through the unit metal plate 10.

[0081] Reference Fig.10, light passing through the first surface hole H1 and the second surface hole H2 may be confirmed on the support layer 20. Specifically, a first transmission area TA1 and a second transmission area TA2 may be confirmed on the support layer 20. The first transmission area TA1 is an area passing through the first surface hole H1. The second transmission area TA2 is an area passing through the second surface hole H2. The first transmission area TA1 and the second transmission area TA2 have different sizes.

[0082] The DPU (defects per unit) is confirmed by the number of the second transmission areas TA2. That is, the first transmission area TA1 is an area passing through the first surface H1 formed by the first inclusions. When confirming the number of DPU (defects per unit), the number of the first transmission areas TA1 is excluded.

[0083] Next, refer to Figure 1 In the fifth step, it is determined whether the unit metal plate 10 is normal or defective by DPU (Defects Per Unit). That is, if the number of second transmission areas of the unit size (L×W×X) is less than or equal to the set range, the unit metal plate 10 is determined to be normal.

[0084] In addition, if the number of the second transmission regions of the unit size (L×W×X) of the metal plate is greater than or equal to a set range, the unit metal plate 10 is determined to be defective.

[0085] For example, the unit metal plate 10 may have a length (L) of 900 mm to 1100 mm, a width (W) of 290 mm to 300 mm, and a thickness (X) of 3 μm to 10 μm. If the number of DPUs (defects per unit) of the unit size (L×W×X) of the metal plate is 10 or less, it is determined to be normal. Specifically, if the number of DPUs (defects per unit) of the unit size (L×W×X) of the metal plate is 0 or more and 10 or less, or 1 or more and 10 or less, it is determined to be normal. In addition, if the number of DPUs exceeds 10, it is determined to be defective.

[0086] Specifically, the metal plate 10 may have a length (L) of 900 mm to 1100 mm, a width (W) of 290 mm to 300 mm, and a thickness (X) of 3 μm to 10 μm. If the number of inclusions whose size exceeds the thickness (X) of the unit metal plate 10 is 10 or less, it is determined to be normal. In addition, if the number of inclusions whose size exceeds the thickness (X) of the unit metal plate 10 exceeds 10, it is determined to be defective.

[0087] Specifically, if the deposition mask is manufactured with a metal plate having a DPU (defects per unit) of 10 or less, defects of the through-holes formed in the metal plate 10 may be minimized. However, if the deposition mask is manufactured with a metal plate having a DPU (defects per unit) greater than 10, the size or shape of the through-holes formed in the metal plate 10 may be changed. Therefore, the quality of the deposition pattern formed by the deposition mask may be reduced.

[0088] Example 1

[0089] A unit metal plate having a length (L) of 900 mm, a width (W) of 290 mm, and a thickness (X) of 3 μm to 10 μm was manufactured. Then, the number of DPUs was measured by a metal plate testing method.

[0090] Next, three deposition masks are manufactured using the unit metal plate, and 70 million through holes are formed in each deposition mask.

[0091] Next, the defects of the through-holes are confirmed based on the number of DPUs (defects per unit) in one deposition mask. The inclusions of DPUs (defects per unit) are inclusions whose size exceeds the thickness (X) of the unit metal plate.

[0092] In addition, defects such as through-hole Fig.17 For example, Fig.17 As shown in (a), a through hole with a larger diameter than other through holes is determined as a defect. Fig.17 As shown in (b), the through holes connected to each other are determined as defects. Fig.17 As shown in (c), a through hole with a smaller diameter than other through holes is determined as a defect.

[0093] Example 2

[0094] A unit metal plate having a length (L) of 1000 mm, a width (W) of 300 mm, and a thickness (X) of 3 μm to 10 μm was manufactured. Then, the number of DPUs was measured using the metal plate test method. Then, the defects of the through holes of the deposition mask were confirmed in the same manner as in Example 1.

[0095] Example 3

[0096] A unit metal plate having a length (L) of 1100 mm, a width (W) of 310 mm, and a thickness (X) of 3 μm to 10 μm was manufactured. Then, the number of DPUs was measured using the metal plate test method. Then, the defects of the through holes of the deposition mask were confirmed in the same manner as in Example 1.

[0097] [Table 1]

[0098]

[0099]

[0100] [Table 2]

[0101]

[0102]

[0103] [Table 3]

[0104]

[0105]

[0106] Table 1 shows the results according to Example 1. Table 2 shows the results according to Example 2. Table 3 shows the results according to Example 3. In addition, Fig.11 This is a photograph of Experimental Example 9 of Example 1. Fig.12 This is a photograph of Experimental Example 10 of Example 1.

[0107] Referring to Tables 1 to 3, it can be seen that when the number of inclusions exceeding the thickness of the unit metal plate exceeds 10, the through-hole defect rate increases significantly.

[0108] The embodiment controls the DPU (defects per unit) of the unit metal plate within a set range. Therefore, the defects of the through holes of the deposition mask manufactured using the unit metal plate are reduced. Therefore, the deposition mask manufactured using the unit metal plate improves deposition quality and deposition reliability.

[0109] In addition, the normality and defects of the unit metal plate can be confirmed in advance before manufacturing the deposition mask. Therefore, the process of manufacturing the deposition mask using the unit metal plate subjected to defect determination is prevented. Therefore, the processing efficiency is improved.

[0110] Deposition mask

[0111] In the following, reference will be made to Figures 13 to 15 A deposition mask according to an embodiment is described.

[0112] Reference Fig.13 and Fig.14 , the organic deposition apparatus includes a deposition mask 100 , a mask frame 200 , a deposition substrate 300 , an organic deposition container 400 , and a vacuum chamber 500 .

[0113] The deposition mask 100 is formed of the above-mentioned metal plate 10. The deposition mask 100 includes a plurality of through holes TH. The through holes are provided in the effective portion. The through holes are provided to correspond to a pixel pattern to be formed on the deposition substrate.

[0114] The mask frame 200 includes an opening 205. A plurality of through holes are provided on a region corresponding to the opening 205. Thus, the organic material supplied to the organic deposition container 400 is deposited on the deposition substrate 300. The deposition mask 100 is provided and fixed on the mask frame 200. For example, the deposition mask 100 is tensioned with a constant tension. In addition, the deposition mask 100 is welded and fixed on the mask frame 200.

[0115] For example, the ineffective area of ​​the deposition mask 100 is welded. Thus, the deposition mask 100 is fixed on the mask frame 200. Then, the outwardly protruding portion of the mask frame 200 is cut and removed.

[0116] The mask frame 200 includes metal having high rigidity. Therefore, deformation of the mask frame is reduced during the welding process.

[0117] The deposition substrate 300 is a substrate used when manufacturing a display device. For example, an OLED pixel pattern is formed on the deposition substrate 300. On the deposition substrate 300, organic patterns of red, green, and blue are formed to form pixels, which are the three primary colors of light. That is, an RGB pattern is formed on the deposition substrate 300.

[0118] The organic deposition container 400 is a crucible. The organic material is disposed inside the crucible. The organic deposition container 400 moves within the vacuum chamber 500. That is, the organic deposition container 400 moves in one direction within the vacuum chamber 500. For example, the organic deposition container 400 moves in the width direction of the deposition mask 100 within the vacuum chamber 500.

[0119] A heat source and / or an electric current is supplied to the organic deposition container 400 . Thus, an organic material is deposited on the deposition substrate 300 .

[0120] Reference Fig.15 , the deposition mask 100 includes a first surface 1S and a second surface 2S opposite to the first surface.

[0121] The first surface 1S includes small surface holes V1. The second surface 2S includes large surface holes V2. For example, a plurality of small surface holes V1 and a plurality of large surface holes V2 are formed on the first surface 1S and the second surface 2S, respectively.

[0122] In addition, the deposition mask 100 includes a through hole TH. The through hole TH is formed by a connection portion CA connecting boundaries of the small-surface hole V1 and the large-surface hole V2.

[0123] The width of the large surface hole V2 is greater than the width of the small surface hole V1. The width of the small surface hole V1 is measured at the first surface 1S of the deposition mask 100. The width of the large surface hole V2 is measured at the second surface 2S of the deposition mask 100.

[0124] In addition, the width of the connection portion CA has a set size. Specifically, the width of the connection portion CA may be 15 μm to 33 μm. More specifically, the width of the connection portion CA may be 19 μm to 33 μm. More specifically, the width of the connection portion CA may be 20 μm to 27 μm. If the width of the connection portion CA exceeds 33 μm, it is difficult to achieve a resolution of 500 PPI or higher. In addition, if the width of the connection portion CA is less than 15 μm, defects may occur during the deposition process.

[0125] The small surface hole V1 faces the deposition substrate 300. The small surface hole V1 is disposed close to the deposition substrate 300. Therefore, the small surface hole V1 has a shape corresponding to the deposition pattern DP.

[0126] The large surface hole V2 faces the organic material deposition container 400. Therefore, the organic material supplied from the organic material deposition container 400 can be accommodated with a wider width through the large surface hole V2. In addition, a fine pattern can be quickly formed on the deposition substrate 300 through the small surface hole V1.

[0127] Therefore, the organic material contained in the large surface hole V1 is deposited on the deposition substrate 300 through the small surface hole V1. Therefore, one of the red, green or blue pixel patterns is formed on the deposition substrate 300. Subsequently, the process is repeated. Therefore, all patterns of the red, green or blue pixel patterns are formed on the deposition substrate 300.

[0128] Reference Fig.16 , the deposition mask 100 according to an embodiment includes a deposition area DA and a non-deposition area NDA.

[0129] The deposition area DA is an area for forming a deposition pattern. The deposition area DA includes an active area AA and an inactive area UA. The active area AA is an area in which a through hole TH is formed, through which an organic material passes. In addition, the inactive area UA is an area in which a through hole TH is not formed. In addition, a through hole TH may be formed in the inactive area UA. However, the through hole TH of the inactive area UA does not allow the organic material to pass therethrough.

[0130] In the drawings, the active area AA is shown as a square shape. However, the embodiment is not limited thereto. The active area AA may be a rectangular shape or a circular shape.

[0131] The active area AA includes a plurality of active areas, and the plurality of active areas are spaced apart in the first direction.

[0132] The deposition area DA may be an area from a point where the first active area starts in the first direction to a point where the last active area ends.

[0133] In addition, the deposition area DA may be an area from a point where the first inactive area starts in the first direction to a point where the last inactive area ends.

[0134] The unavailable area UA is a deposition area other than the active area AA. The unavailable area UA may be divided into a first unavailable area UA1 and a second unavailable area UA2 according to a location.

[0135] The first unavailable area UA1 is an area between the active areas AA. Therefore, a plurality of first unavailable areas UA1 are spaced apart in the first direction. In addition, the second unavailable area UA2 is an area between the active area AA and both ends in the second direction.

[0136] The non-deposition area NDA is an area that does not participate in deposition. The non-deposition area NDA includes a frame fixing area. The frame fixing area is an area for fixing the deposition mask 100 to the mask frame 200. In addition, the non-deposition area NDA may include at least one of a half-etched portion and an opening portion OA. The half-etched portion HF is formed by partially etching the metal plate 10. The opening portion OA is formed by etching the metal plate 10 as a whole.

[0137] The residual stress generated when the deposition mask 100 is tensioned is dispersed by the half-etched portion HF. Therefore, the undulation of the deposition mask is reduced.

[0138] In addition, a jig (eg, a clip) used when tensioning the deposition mask 100 is fixed to the opening portion OP.

[0139] The through hole TH is provided in the active area AA. Specifically, the through hole TH including the small surface hole V1, the large surface hole V2, the small surface hole V1 and the connection portion CA is provided in the active area AA.

[0140] The deposition mask 100 may have a DPU (defects per unit) within a set range.

[0141] The DPU (defects per unit) of the deposition mask 100 can be confirmed by sampling a sample. In detail, a specific area (length (a) × width (b)) on the plane of the deposition mask 100 is selected. Then, a sample (a×b×t1) corresponding to the thickness (t1) of the deposition mask 100 is sampled. Then, the DPU (defects per unit) is confirmed by a test method. Specifically, a support layer is provided on one surface of the sample. Then, the other surface of the sample is etched to adjust the thickness of the sample to a test thickness (t2). Then, light is irradiated to the sample to confirm the DPU (defects per unit).

[0142] The DPU (Defects Per Unit) of a deposition mask is the number of inclusions of a set size per size sample. Specifically, the DPU (Defects Per Unit) is the number of inclusions whose size exceeds the test thickness (t2) per size sample. The test thickness (t2) can be 3 μm to 10 μm.

[0143] For example, the sample (S) may be sampled into 30 mm×60 mm×t1 (first sample), 60 mm×30 mm×t1 (second sample), or 60 mm×60 mm×t1 (third sample).

[0144] The sample (S) may be sampled from various regions of the deposition mask 100. Specifically, the sample (S) may be sampled from at least one of the non-deposition area NDA, the first unavailable area UA1, and the second unavailable area UA2.

[0145] The DPU (defects per unit) of the deposition mask may vary according to the size of the sample (S). Specifically, when the size of the sample is 30 mm×60 mm×t1 or 60 mm×30 mm×t1, the DPU (defects per unit) may be 1 or less. In addition, when the size of the sample is 60 mm×60 mm×t1, the DPU (defects per unit) may be 3 or less.

[0146] If the number of DPUs (defects per unit) exceeds the above range, defects of the through-holes may increase, and thus, the quality of the deposition pattern formed on the deposition substrate may be reduced.

[0147] Example 4

[0148] A deposition area and a non-deposition area were defined on a metal plate with a length of 30 mm, a width of 100 mm, and a thickness of 25 μm. Then, a plurality of through holes were formed in the deposition area to manufacture a deposition mask. The number of through holes formed was about 70 million.

[0149] The DPU is then measured using the test method.

[0150] Specifically, a sample of 30 mm × 60 mm × t1 (length × width × thickness) is sampled from the non-deposition area of ​​the deposition mask. Then, a support layer is set on one surface of the sample. In addition, the thickness of the sample is controlled on the other surface of the sample. Specifically, the thickness of the sample is controlled to be a test thickness (t2). Then, light is irradiated from the lower side of the other surface of the sample. Then, the number of DPUs is measured by the size and number of light-transmitting areas transmitted by the support layer. At this time, the test thickness (t2) is 3 μm to 10 μm.

[0151] Then, the presence or absence of defects in the through-holes is checked based on DPU (Defects Per Unit) The size of the inclusions in DPU (Defects Per Unit) exceeds the test thickness (t2) of the sample.

[0152] In addition, defects in the through-holes such as Fig.17 shown.

[0153] Example 5

[0154] A deposition mask was manufactured using a metal plate having a length of 340 mm, a width of 100 mm, and a thickness of 20 μm. A sample of 60 mm × 30 mm × t1 (length × width × thickness) was sampled from an invalid area of ​​the deposition area of ​​the deposition mask. No through-holes were formed in the invalid area. The number of DPUs of the deposition mask was measured using the sample. Then, the presence of defects in the through-holes of the deposition mask was checked in the same manner as in Example 4.

[0155] Example 6

[0156] A deposition mask was manufactured using a metal plate having a length of 320 mm, a width of 100 mm, and a thickness of 30 μm. A sample of 60 mm × 60 mm × t1 (length × width × thickness) was sampled from an invalid area of ​​the deposition area of ​​the deposition mask. No through-holes were formed in the invalid area. The number of DPUs of the deposition mask was measured using the sample. Then, the presence of defects in the through-holes of the deposition mask was checked in the same manner as in Example 4.

[0157] [Table 4]

[0158]

[0159]

[0160] [Table 5]

[0161]

[0162]

[0163] [Table 6]

[0164]

[0165]

[0166] Table 4 shows the results according to Example 4. Table 5 shows the results according to Example 5. Table 6 shows the results according to Example 6. Referring to Tables 4 and 5, when the DPU (defects per unit) of the deposition mask exceeds 1, the through-hole defect rate significantly increases. In addition, referring to Table 6, when the DPU (defects per unit) of the deposition mask exceeds 3, the through-hole defect rate significantly increases.

[0167] Therefore, the embodiment controls the DPU (defects per unit) within a set range. Therefore, the defects of the through hole are reduced. Therefore, the deposition mask improves the deposition quality and deposition reliability.

[0168] In addition, after manufacturing the deposition mask, the deposition quality and deposition reliability of the deposition mask can be confirmed in advance by the size of the DPU (defects per unit). Therefore, only the deposition mask with a small defect rate of the through hole can be selectively selected and the deposition process can be performed. Therefore, the efficiency of the deposition process is improved.

[0169] The characteristics, structures and effects described in the above embodiments are included in at least one embodiment, but are not limited to one embodiment. In addition, the characteristics, structures and effects shown in each of the embodiments can even be combined or modified by a person of ordinary skill in the art to which the embodiments belong relative to other embodiments. Therefore, it should be understood that the contents related to such combinations and such modifications are included in the scope of the embodiments.

[0170] The above description has focused on the embodiments, but is exemplary only and does not limit the embodiments. It will be appreciated by those skilled in the art that various modifications and applications not shown above are possible without departing from the basic features of the embodiments. For example, each component specifically indicated in the embodiments may be modified and implemented. In addition, it should be understood that differences associated with such changes and applications are included within the scope of the embodiments defined in the appended claims.

Claims

1. A metal plate having a length (L) of 900 mm to 1100 mm, a width (W) of 290 mm to 300 mm, and a thickness (T) of 15 μm to 100 μm, the metal plate comprising: in, The metal plate comprises Invar alloy, wherein the thickness of the metal plate is adjusted to a test thickness (X) of 3 μm to 10 μm to form a unit metal plate having a unit size of L×W×X, wherein the number of inclusions per unit size of the unit metal plate is 10 or less, and Wherein, the inclusion has a size exceeding the test thickness.

2. The metal plate according to claim 1, wherein The inclusions include at least one element selected from the group consisting of carbon, oxygen, magnesium, aluminum, silicon, sulfur, calcium and iron.

3. A deposition mask comprising: Sedimentary and non-sedimentary areas, wherein the deposition area includes an effective area in which a through hole is formed and an ineffective area other than the effective area, wherein the through hole is formed by a small surface hole, a large surface hole, and a connecting portion connecting the small surface hole and the large surface hole, A first sample of 30 mm (length) × 60 mm (width) × t1 (thickness) is obtained by sampling at least one of the invalid area and the non-deposition area, and Wherein, when the thickness of the first sample is adjusted to a test thickness (t2), the number of inclusions having a size exceeding the test thickness in the first sample is 1 or less.

4. The deposition mask according to claim 3, wherein: The inclusions include at least one element selected from the group consisting of carbon, oxygen, magnesium, aluminum, silicon, sulfur, calcium and iron.

5. The deposition mask according to claim 4, wherein: A second sample of 60 mm (length)×30 mm (width)×t1 (thickness) is obtained by sampling at least one of the ineffective area and the non-deposition area, and Wherein, when the thickness of the second sample is adjusted to the test thickness (t2), the number of inclusions having a size exceeding the test thickness in the second sample is 1 or less.

6. The deposition mask according to claim 4, wherein: A third sample of 60 mm (length)×60 mm (width)×t1 (thickness) is obtained by sampling at least one of the ineffective area and the non-deposition area, and Wherein, when the thickness of the third sample is adjusted to the test thickness (t2), the number of inclusions in the third sample whose size exceeds the test thickness is 3 or less.

7. A testing method comprising: preparing a unit metal plate; placing a support layer on one surface of the unit metal plate; Controlling the thickness of the unit metal plate; Checking the DPU (defects per unit) of the unit metal sheet; as well as Determine the unit metal plate, Herein, inspecting the DPU (defects per unit) of the unit metal plate includes inspecting the number of inclusions of the unit metal plate by irradiating light onto the unit metal plate.

8. The testing method according to claim 7, wherein: Controlling the thickness of the unit metal plate includes changing the thickness of the unit metal plate to a test thickness of 3 μm to 10 μm, and Wherein, the inclusion has a size exceeding the test thickness.

9. The testing method according to claim 8, wherein: When the light is irradiated onto the unit metal plate, a first transmission area with a size smaller than the test thickness and a second transmission area with a size larger than the test thickness are formed on the support layer, and The inclusions are checked by the number of the second transmission areas.

10. The testing method according to claim 7, wherein: The inclusions include at least one element selected from the group consisting of carbon, oxygen, magnesium, aluminum, silicon, sulfur, calcium and iron.

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