Mask inspection apparatus and mask inspection method

Abstract

To provide a mask inspection device and a mask inspection method.SOLUTION: A mask inspection method of one embodiment of the invention includes the steps of: preparing a mask for vapor deposition, the mask including multiple first opening parts and multiple second opening parts, each of the first opening parts having a shape different from the shape of each of the second opening parts on a plane surface; designating a first group and a second group, each of which includes at least one of the first opening parts and at least one of the second opening parts; comparing an image of the first group and an image of the second group; and judging whether the first group and the second group are defective based on a result of comparing the image of the first group and the image of the second group. An array of the first opening part and the second opening part included in the first group is the same as that of the first opening part and the second opening part included in the second group.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a mask inspection apparatus and a mask inspection method. [Background technology]

[0002] Organic light-emitting diode displays (OLEDs) are gaining attention as next-generation flat panel displays because they generally have excellent brightness and viewing angle characteristics and, unlike LCDs, do not require a separate light source. Because OLEDs do not require a separate light source, they can be manufactured to be lightweight and thin. Furthermore, OLEDs have characteristics such as low power consumption, high brightness, and fast response speed.

[0003] An organic light emitting display device includes a plurality of organic light emitting elements, each of which includes an anode, an organic light emitting layer, and a cathode. When manufacturing the organic light emitting elements, a deposition mask is placed on a substrate, and organic materials for forming the organic light emitting layer are applied onto the substrate through openings in the deposition mask. As technology advances and demand for higher resolution displays increases, the number of organic light emitting elements in a display device is increasing.

[0004] As the number of organic light-emitting devices increases, the number of openings in deposition masks used to manufacture organic light-emitting layers also increases. Such deposition masks are typically made of metal-containing materials, but due to manufacturing issues, the openings may not all be accurately formed in the desired pattern. This can result in defects in the deposition pattern. To prevent this, masks are inspected in advance. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a mask inspection apparatus and a mask inspection method that can collectively inspect for defects in masks that include openings with different shapes.

[0006] The problems to be solved by the present invention are not limited to those mentioned above, and unmentioned technical problems and other technical problems will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0007] According to one embodiment of the present invention, a mask inspection method includes the steps of preparing an deposition mask including a plurality of first openings and a plurality of second openings, each of the first openings having a different shape in a plane from each of the second openings; designating a first group and a second group each including at least one of the first openings and at least one of the second openings; comparing an image of the first group with an image of the second group; and determining whether the first group and the second group are defective based on a result of comparing the image of the first group with the image of the second group, wherein an arrangement of the first openings and the second openings included in the first group is the same as an arrangement of the first openings and the second openings included in the second group.

[0008] Comparing the first group of images to the second group of images may include comparing an area of ​​the first group to an area of ​​the second group.

[0009] Before the step of comparing the first group and the second group, the method may further include the step of photographing the first group and the second group using a vision unit including a CCD sensor having a plurality of pixels to obtain an image of the first group and an image of the second group.

[0010] The step of comparing the area of ​​the first group with the area of ​​the second group may include the step of comparing the number of a portion of the pixels of the CCD sensor that are arranged in the first group with the number of another portion of the pixels of the CCD sensor that are arranged in the second group.

[0011] Comparing the first group of images to the second group of images may include comparing shapes of the first group to shapes of the second group.

[0012] The method may further include a step of photographing the first group and the second group using a vision unit including a CCD sensor including a plurality of pixels, and the step of comparing the shape of the first group with the shape of the second group may include a step of comparing the shape of a portion of the pixels of the CCD sensor that are arranged in the first group with the shape of another portion of the pixels of the CCD sensor that are arranged in the second group.

[0013] Comparing the first group and the second group may further include horizontally rotating one of the images in the first group and the images in the second group.

[0014] Comparing the first group of images with the second group of images may include comparing with the naked eye of an examiner.

[0015] According to one embodiment of the present invention, a mask inspection method includes the steps of: preparing a deposition mask including a plurality of first openings and a plurality of second openings, wherein each of the first openings has a different shape in a plane from each of the second openings; preparing a reference image including the first openings and the second openings; designating a plurality of groups each including the first openings and the second openings; comparing the reference image with an image of the group; and determining whether the group is defective based on a result of comparing the reference image with the image of the group, wherein an arrangement of the first openings and the second openings included in the group may be the same as an arrangement of the first openings and the second openings included in the reference image.

[0016] The step of comparing the reference image with the image of the group may include the step of comparing the areas of the first opening and the second opening included in the reference image with the areas of the first opening and the second opening included in the group.

[0017] The step of comparing the reference image with the image of the group may include the step of comparing the shapes of the first opening and the second opening included in the reference image with the shapes of the first opening and the second opening included in the group.

[0018] Comparing the reference image and the group of images may include visually comparing with an examiner.

[0019] According to one embodiment of the present invention, a mask inspection apparatus inspects a deposition mask including a plurality of first openings and a plurality of second openings, each having a different shape from each of the first openings on a plane. The mask inspection apparatus includes a support stage that supports the deposition mask, a vision unit that is spaced apart from the support stage and photographs the deposition mask, and a control unit that determines whether the first openings and the second openings are defective based on images acquired by the vision unit. The control unit designates a first group and a second group that each include at least one of the plurality of first openings and at least one of the second openings, and compares a first image captured of the first group with a second image captured of the second group.

[0020] The control unit may include a comparison unit that compares the area of ​​the first group with the area of ​​the second group.

[0021] The vision unit may further include a light emitting element that emits light toward the deposition mask, and a light receiving element that receives at least a portion of the light emitted from the light emitting element and includes a CCD sensor having a plurality of pixels.

[0022] The comparison unit may compare the number of partial pixels arranged in the first group among the pixels of the CCD sensor with the number of other partial pixels arranged in the second group among the pixels of the CCD sensor.

[0023] The comparison unit can compare the planar shape of the first group with the planar shape of the second group.

[0024] The control unit may further include a foreign matter detection unit that determines whether or not a foreign matter is present on the deposition mask.

[0025] The device may further include an output unit that outputs information on whether or not the device is defective as determined by the control unit.

[0026] The image processing device may further include a data processing unit that processes image information captured by the vision unit and provides the processed image information to the control unit.

[0027] Further details of one embodiment are included in the detailed description and drawings. [Effects of the Invention]

[0028] According to the mask inspection apparatus and mask inspection method of the embodiment, defects in masks including openings with mutually different shapes can be inspected collectively.

[0029] The effects of one embodiment are not limited to the above-mentioned examples, and many more effects are included in this specification. [Brief explanation of the drawings]

[0030] [Figure 1] 1 is a side view schematically showing a mask inspection apparatus according to an embodiment; [Figure 2] FIG. 2 is an enlarged plan view of a partial area of ​​the mask. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III' in FIG. 2. [Figure 4]FIG. 4 is a diagram schematically showing a process of vapor deposition using the vapor deposition masks of FIGS. 2 and 3. [Figure 5] 1 is a cross-sectional view schematically illustrating an organic light emitting display device manufactured using a deposition mask. [Figure 6] 1 is a flowchart illustrating a mask inspection method according to an embodiment. [Figure 7] 1 is a plan view simply illustrating a mask inspection method according to an embodiment. [Figure 8] FIG. 10 is a plan view simply illustrating a mask inspection method according to another embodiment. [Figure 9] FIG. 10 is a schematic layout diagram showing a pixel array of a display device according to another embodiment. [Figure 10] FIG. 10 is a plan view simply showing a mask inspection method according to still another embodiment. [Figure 11] FIG. 10 is a schematic layout diagram showing a pixel array of a display device according to yet another embodiment. [Figure 12] FIG. 10 is a side view schematically showing a mask inspection apparatus according to still another embodiment. [Figure 13] 10 is a flowchart illustrating a mask inspection method according to yet another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0031] The advantages and features of the present invention, as well as methods for achieving them, will become clearer in the following detailed embodiments along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be realized in various different forms. The present embodiments are merely for disclosing the present invention and for disclosing the scope of the invention to those skilled in the art. The present invention is defined by the scope of the claims.

[0032] When elements or layers are referred to as being "on" another element or layer, this includes cases where the element or layer is directly on top of the other element or has other layers or elements interposed therebetween. Like reference numerals refer to like elements throughout the specification.

[0033] Although terms such as "first," "second," etc. are used to describe various components, it should be understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, a first component referred to below may be a second component within the technical concept of the present invention.

[0034] Hereinafter, specific embodiments will be described with reference to the accompanying drawings.

[0035] FIG. 1 is a side view schematically showing a mask inspection apparatus according to an embodiment.

[0036] Referring to FIG. 1, a mask inspection apparatus 10 according to an embodiment may include a support table 110, a vision unit 120, a data processing unit 130, a control unit 140, and an output unit 150.

[0037] The support 110 may provide a space in which the deposition mask 20, which is an object to be inspected, can be placed. That is, the deposition mask 20 may be placed on the support 110. The support 110 may include transparent glass or the like through which light emitted from the light irradiation member 121 can pass.

[0038] 1, the support 110 may fix the deposition mask 20 in a tensioned state. In this case, the support 110 may include clamps (not shown) that fix both sides of the deposition mask 20, and a cylinder or gear and motor that linearly move the clamps (not shown) to tension the deposition mask 20. The support 110 may further include a mask frame (not shown), and the deposition mask 20 may be attached to the mask frame (not shown), but this is not limited to the example shown here.

[0039] Furthermore, although not shown in the drawings, the mask inspection apparatus 10 may further include a moving member (not shown), and the support table 110 may be connected to the moving member (not shown) and moved by the moving member (not shown).

[0040] The vision unit 120 may be disposed above and / or below the deposition mask 20 to capture an image of the surface shape of the deposition mask 20. The vision unit 120 may be spaced apart from the support 110 and the target substrate 20. The vision unit 120 may generate an image by capturing an image of the deposition mask 20 and transmit the captured image to the control unit 140. The vision unit 120 may include a light emitting member 121 and a light receiving member 122.

[0041] The light irradiation member 121 is disposed under the support 110 and can emit light toward the support 110. The light irradiation member 121 can emit light toward the target substrate 20 seated on the support 110.

[0042] The light receiving member 122 may be disposed on top of the support stage 110. The light receiving member 122 may face the light irradiating member 121 with the target substrate 20 interposed therebetween. The light receiving member 122 may receive light emitted from the light irradiating member 121, thereby capturing an image of the deposition mask 20. That is, at least a portion of the light emitted from the light irradiating member 121 may pass through the openings (OP1, OP2, see FIGS. 2 and 3 ) of the deposition mask 20 and reach the light receiving member 122, thereby allowing the light receiving member 122 to capture an image of the deposition mask 20.

[0043] The light receiving member 122 may include a CCD sensor, etc., but is not limited to the example shown here. When the light receiving member 122 includes a CCD sensor, the CCD sensor may be a two-dimensional sensor and may include an imaging area in which a certain number of pixels are arranged. For example, but not limited to the example shown here, the CCD sensor may have an imaging area of ​​2048 pixels x 512 pixels (144 μm x 36 μm when one pixel is 70 nm x 70 nm). In other words, the CCD sensor may be composed of multiple rows (e.g., 512 rows) of lines in one direction, and each row may be composed of multiple pixels (e.g., 2048 pixels).

[0044] The data processing unit 130 may process image information captured by the vision unit 120. The data processing unit 130 may convert the image information received from the vision unit 120 into a format suitable for transmission and provide it to the control unit 140. The data processing unit 130 may provide necessary information to the control unit 140 via wired or wireless communication.

[0045] The control unit 140 can designate opening groups (GR1 to GR6, see FIG. 2) including openings of different shapes (OP1, OP2, see FIG. 2) based on the data (image information) received from the data processing unit 130, and can determine whether there is a defect in the deposition mask 20. The control unit 140 can include a comparison unit 141 that compares the data (image information) and a determination unit 142 that determines whether there is a defect based on the comparison result.

[0046] The method by which the control unit 140 determines whether the deposition mask 20 is defective is not limited to the example shown here, but may be, for example, a method of comparing images obtained by photographing the same pattern at different positions (die-to-die inspection method), or a method of comparing an image obtained by photographing a reference image generated from drawing data used in forming the deposition mask 20 with an image obtained by photographing the actual mask pattern (die-to-database inspection method). The method of inspecting the deposition mask 20 will be described later.

[0047] The control unit 140 may be formed in various forms, and is not limited to the examples shown here. For example, the control unit 140 may be provided in a separately installed terminal, personal computer, notebook, PDA, etc., or may be provided on a circuit board installed inside together with other components rather than as a separate device.

[0048] The output unit 150 may output information regarding whether the deposition mask 20 is defective, as determined by the control unit 140. The output unit 150 may output information regarding openings determined to be normal and openings determined to be defective among the openings (OP1, OP2, see FIGS. 2 and 3) of the deposition mask 20. The information may include coordinate information indicating the positions of openings determined to be defective among the openings (OP1, OP2, see FIGS. 2 and 3) of the deposition mask 20. Thus, a user can selectively correct the openings determined to be defective to normal openings, or can replace the deposition mask 20 itself and perform a deposition process if the number of openings determined to be defective is equal to or greater than a certain number.

[0049] The deposition mask 20 may include at least two or more openings OP1 and OP2 having different shapes on a plane. For a more detailed description of the deposition mask 20, reference will be made to FIGS.

[0050] Fig. 2 is an enlarged plan view of a portion of the mask, and Fig. 3 is a cross-sectional view taken along line III-III' in Fig. 2.

[0051] 2 and 3, in the drawings, a first direction DR1 indicates the horizontal direction of the deposition mask 20 in a plan view, and a second direction DR2 indicates the vertical direction of the deposition mask 20 in a plan view. A third direction DR3 indicates the thickness direction of the deposition mask 20. The first direction DR1 and the second direction DR2 intersect perpendicularly with each other, and the third direction DR3 intersects the first direction DR1 and the second direction DR2 perpendicularly to a plane on which the first direction DR1 and the second direction DR2 are placed. However, it should be understood that the directions referred to in one embodiment refer to relative directions, and the embodiment is not limited to the referred directions.

[0052] The deposition mask 20 includes a blocking portion BL and a plurality of openings OP1 and OP2 formed within the blocking portion BL. The blocking portion BL can serve to block the advancement of the deposition material. The blocking portion BL can include a blocking member. The blocking member is made of a metal such as nickel (Ni), a nickel alloy, or a nickel-cobalt alloy. The blocking member is made of a metal foil film, but is not limited to the example shown here.

[0053] The openings OP1 and OP2 are formed inside the blocking portion BL and have a shape penetrating the material layer constituting the blocking portion BL in the thickness direction (third direction DR3). The openings OP1 and OP2 allow the deposition material to pass through so that a pattern corresponding to the shape of the openings OP1 and OP2 is formed on the target substrate (330, see FIG. 4).

[0054] The deposition mask 20 may include one surface 20a and another surface 20b. The one surface 20a and the other surface 20b of the deposition mask 20 may be opposite surfaces to each other. Although not limited to the example shown here, for example, the one surface 20a of the deposition mask 20 may be a surface facing a target substrate (330, see FIG. 4), and the other surface 20b may be an opposite surface facing a crucible (not shown).

[0055] The deposition mask 20 may further include a first inner surface S1 and a second inner surface S2. The first inner surface S1 faces the first opening OP1 at the blocking portion BL, and the second inner surface S2 faces the second opening OP2 at the blocking portion BL. That is, the inner wall of the first opening OP1 may include the first inner surface S1, and the inner wall of the second opening OP2 may include the second inner surface S2.

[0056] The deposition mask 20 may further include a first one-side end BE1, a first other-side end UE1, a second one-side end BE2, and a second other-side end UE2. The first one-side end BE1 refers to a portion where one surface 20a of the deposition mask 20 and the first inner surface S1 contact each other, and the first other-side end UE1 refers to a portion where the other surface 20b of the deposition mask 20 and the first inner surface S1 contact each other. The second one-side end BE2 refers to a portion where one surface 20a of the deposition mask 20 and the second inner surface S2 contact each other, and the second other-side end UE2 refers to a portion where the other surface 20b of the deposition mask 20 and the second inner surface S2 contact each other.

[0057] The openings OP1 and OP2 of the deposition mask 20 may have different shapes on a plane. The openings OP1 and OP2 of the deposition mask 20 may have at least two or more shapes on a plane. The deposition mask 20 may include at least two or more openings OP1 and OP2 having different shapes on a plane. The deposition mask 20 may include a first opening OP1 and a second opening OP2 having different shapes on a plane.

[0058] In plan view, the first one-side end portion BE1 surrounds the first other-side end portion UE1, and the planar shapes of the first one-side end portion BE1 and the first other-side end portion UE1 correspond to each other. In plan view, the second one-side end portion BE2 surrounds the second other-side end portion UE2, and the planar shapes of the second one-side end portion BE2 and the second other-side end portion UE2 correspond to each other. That is, the planar shape of the first one-side end portion BE1 may be different from the planar shape of the second one-side end portion BE2, and the planar shape of the first other-side end portion UE1 may be different from the planar shape of the second other-side end portion UE2.

[0059] The first openings OP1 and the second openings OP2 may be spaced apart from each other and alternately arranged along the first direction DR1 and the second direction DR2. That is, the first openings OP1 and the second openings OP2 may be alternately arranged in the first direction DR1, and the first openings OP1 and the second openings OP2 may be alternately arranged in the second direction DR2.

[0060] At least some of the multiple first openings OP1 may be arranged rotated clockwise within a range of more than 0° and less than 360° on a plane. Alternatively, they may be flipped left and right in the first direction DR1 and flipped up and down in the second direction DR2 on the drawing. Furthermore, at least some of the multiple second openings OP2 may be arranged rotated clockwise within a range of more than 0° and less than 360° on a plane. Alternatively, they may be flipped left and right in the first direction DR1 and flipped up and down in the second direction DR2 on the drawing.

[0061] The deposition mask 20 may further include an opening group GR. The opening group GR may include one first opening OP1 and one second opening OP2, but is not limited to the example shown here. That is, the deposition mask 20 may include opening groups GR that include the first openings OP1 and second openings OP2 that are repeatedly arranged, and each of the opening groups GR includes the first openings OP1 and the second openings OP2.

[0062] The aperture groups GR may be repeatedly arranged along the first direction DR1 and the second direction DR2. Some of the aperture groups GR may be rotated clockwise in a range of more than 0° to less than 360° on a plane. Alternatively, they may be flipped left and right in the first direction DR1 and flipped up and down in the second direction DR2 on the drawing.

[0063] The planar and cross-sectional shapes of the openings OP1 and OP2 shown in FIGS. 2 and 3 are merely illustrative, and the shapes are not limited to the examples shown individually.

[0064] FIG. 4 is a diagram schematically showing a deposition process using the deposition masks of FIGS.

[0065] Referring to FIG. 4, according to an embodiment, a process for depositing an organic light emitting layer and electrodes of an organic light emitting display device may be performed in a vacuum chamber 300.

[0066] An evaporation source 310 may be disposed at the bottom of the vacuum chamber 300. The evaporation source 310 is a container containing a deposition material, and may be, for example, a crucible. A deposition mask 20 according to an embodiment may be attached by a support 320 to the upper side of the vacuum chamber 300 facing the evaporation source 310. A target substrate 330, for example, a target substrate 330 for manufacturing an organic light emitting display device, may be disposed on the deposition mask 20. The deposition mask 20 and the target substrate 330 may be in direct contact with each other.

[0067] When the deposition material is evaporated from the evaporation source 310 in the vacuum chamber 300 toward the deposition mask 20, the deposition material can be deposited in a pattern shape on a region of the target substrate 330 through the openings (OP1, OP2, see Figures 2 and 3) formed in the deposition mask 20.

[0068] FIG. 5 is a cross-sectional view schematically illustrating an organic light emitting display device manufactured using a deposition mask.

[0069] 5, the display device 400 may include a base substrate 401. The base substrate 401 may support a structure to be laminated thereon. The base substrate 401 may be an insulating substrate. The base substrate 401 may include a transparent material.

[0070] A buffer film 405 may be disposed on the base substrate 401. The buffer film 405 may be disposed on one surface of the base substrate 401 to protect the thin film transistor TFT and the light emitting element EMD from moisture that may penetrate through the base substrate 401, which is susceptible to moisture permeation.

[0071] A thin film transistor TFT may be disposed as a driving element on the buffer film 405. The thin film transistor TFT may include a semiconductor layer 410, a first insulating layer 421, a second insulating layer 422, and a gate electrode 430.

[0072] A semiconductor layer 410 of the thin film transistor TFT may be disposed on the buffer film 405. The semiconductor layer 410 may include polycrystalline silicon, single crystal silicon, low-temperature polycrystalline silicon, amorphous silicon, or an oxide semiconductor.

[0073] A first insulating layer 421 may be disposed on the semiconductor layer 410. The first insulating layer 421 may be formed of an inorganic film.

[0074] A gate electrode 430 may be disposed on the first insulating layer 421. The gate electrode 430 overlaps the semiconductor layer 410. The gate electrode 430 may be formed of a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0075] A second insulating layer 422 may be disposed on the gate electrode 430. The second insulating layer 422 may be formed of an inorganic film.

[0076] A source electrode 451 (or drain electrode) and a drain electrode 452 (or source electrode) of the thin film transistor TFT may be disposed on the second insulating layer 422. The source electrode 451 and the drain electrode 452 may be connected to the semiconductor layer 410 via contact holes that penetrate the second insulating layer 422 and the first insulating layer 421.

[0077] A third insulating layer 423 may be disposed on the source electrode 451 and the drain electrode 452. The third insulating layer 423 may be a passivation film that protects the lower thin film transistor TFT. The third insulating layer 423 may be formed of an inorganic film.

[0078] A via layer VIA may be disposed on the third insulating layer 423. The via layer VIA may be a planarization film for planarizing steps caused by the thin film transistor TFT. The via layer VIA may include an organic insulating material.

[0079] The light emitting element EMD may be disposed on the via layer VIA. The light emitting element EMD may include a pixel electrode PXE, an emission layer EML, and a common electrode CME.

[0080] Specifically, a pixel electrode PXE may be disposed on the via layer VIA. The pixel electrode PXE may be a first electrode, such as an anode electrode, of the light-emitting element EMD. The pixel electrode PXE may be connected to the drain electrode 452 (or source electrode) of the thin film transistor TFT through a contact hole that penetrates the via layer VIA.

[0081] A pixel defining layer PDL may be disposed on the pixel electrode PXE. The pixel defining layer PDL may be disposed on the pixel electrode PXE and may include an opening that exposes the pixel electrode PXE. The pixel defining layer PDL may include an organic insulating material.

[0082] An emission layer EML may be disposed on the pixel electrode PXE where the pixel defining layer PDL is exposed. The emission layer EML may include an organic material layer. The organic material layer of the emission layer EML may include an organic emission layer and may further include a hole injection / transport layer and / or an electron injection / transport layer.

[0083] A common electrode CME may be disposed on the light-emitting layer EML. The common electrode CME may be a second electrode, such as a cathode electrode, of the light-emitting element EMD. The common electrode CME may be formed in common with the pixels.

[0084] Even if the light-emitting elements EMD of one pixel or one sub-pixel are arranged in different shapes on a plane, if the deposition masks 20 have different shapes, the common layer that is included in common in the light-emitting elements EMD of each pixel or each sub-pixel can be stacked together.

[0085] Furthermore, the mask inspection apparatus (10, see FIG. 1) according to one embodiment can inspect defects in the deposition mask 20 even if the deposition mask 20 includes two or more openings OP1, OP2 having different shapes on a plane. A mask inspection method according to one embodiment will be described below.

[0086] Fig. 6 is a flowchart illustrating a mask inspection method according to an embodiment, and Fig. 7 is a plan view simply illustrating a mask inspection method according to an embodiment.

[0087] 1 and 6 to 7, first, a deposition mask 20 including openings OP1 and OP2 having different shapes is prepared (S10). The deposition mask 20 is substantially similar to the deposition mask 20 described above with reference to FIGS. 2 and 3, and may be seated at a position corresponding to a predetermined region on a support table 110 of the mask inspection apparatus 10 of FIG. 1. The deposition mask 20 may be moved during inspection of the deposition mask 20 using the mask inspection apparatus 10. The deposition mask 20 is moved on the support table 110 by a structure separate from the support table 110, and is fixed to the support table 110 and may be moved as the support table 110 moves.

[0088] Subsequently, an inspection area IA of the deposition mask 20 is designated (S20).

[0089] The inspection area IA may include multiple openings OP1 and OP2. The openings OP1 and OP2 arranged in the inspection area IA may be repeatedly arranged in a certain pattern. That is, the first openings OP1 and the second openings OP2 may be alternately and repeatedly arranged along the first direction DR1, and the first openings OP1 and the second openings OP2 may be alternately and repeatedly arranged along the second direction DR2. Although not limited to the example shown here, adjacent openings OP1 and OP2 arranged in the inspection area IA may be arranged with different shapes. That is, the first openings OP1 and the second openings OP2 having different shapes may be alternately and repeatedly arranged adjacent to each other.

[0090] The inspection area IA may include at least a part of the area that can be collectively photographed via the above-described vision unit 120. In other words, if the vision unit 120 includes a CCD sensor, the inspection area IA may include at least a part of the photographing area that can be photographed by the CCD sensor.

[0091] Although a total of 12 openings OP1, OP2 are arranged in the inspection area IA, the number of openings OP1, OP2 arranged in the inspection area IA is not limited to the example shown here and may be more or less than 12. Furthermore, the step of specifying the inspection area IA (S20) may be omitted.

[0092] Subsequently, some of the repeated openings OP1 and OP2 are grouped into opening groups GR1 to GR6 (S30).

[0093] Of the openings OP1, OP2 arranged in the inspection area IA, at least two adjacent openings OP1, OP2 can be grouped into one opening group GR. While not limited to the example shown here, for example, a first opening OP1 and a second opening OP2 adjacent to each other can be grouped into respective opening groups GR1 to GR6. Each opening group GR1 to GR6 may include the same number of openings OP1, OP2, and may include the same number of first openings OP1 and the same number of second openings OP2. Furthermore, the arrangement (or placement) of the openings OP1, OP2 included in each opening group GR1 to GR6 is substantially similar.

[0094] The aperture groups GR1 to GR6 can be repeatedly arranged within the inspection area IA, that is, the aperture groups GR1 to GR6 can be repeatedly arranged within the inspection area IA along the first direction DR1 and the second direction DR2.

[0095] The aperture groups GR1 to GR6 may be the smallest unit repeated within the inspection area IA. A first opening OP1 and a second opening OP2 may be arranged within the inspection area IA, and the first opening OP1 and the second opening OP2 may be arranged repeatedly. In this case, each of the aperture groups GR1 to GR6 may include one first opening OP1 and one second opening OP2, and the aperture groups GR1 to GR6 may be arranged repeatedly within the inspection area IA. The total number of openings OP1 and OP2 included in each of the aperture groups GR1 to GR6, the number of first openings OP1 included in each of the aperture groups GR1 to GR6, and the number of second openings OP2 included in each of the aperture groups GR1 to GR6 may be the same.

[0096] The openings OP1 and OP2 arranged in the inspection area IA may have different shapes, but the opening groups GR1 to GR6 arranged in the inspection area IA have substantially the same shapes. That is, each of the opening groups GR1 to GR6 includes the same first opening OP1 and second opening OP2, and some of the opening groups GR1 to GR6 (GR2, GR5) may be rotated by a certain angle in the horizontal direction (or with respect to an axis extending in the thickness direction (third direction DR3)). In the drawings, the some of the opening groups (GR2, GR5) are rotated by 180° in the horizontal direction, but the angle of rotation is not limited to the example shown here.

[0097] The opening groups GR1 to GR6 are the smallest units repeated within the inspection area IA, and each of the opening groups GR1 to GR6 is the smallest unit for inspecting defects in the openings OP1 and OP2 of the deposition mask 20. That is, by grouping the first openings OP1 and the second openings OP2 having different shapes into one of the opening groups GR1 to GR6 and inspecting each of the opening groups GR1 to GR6 as a single unit for defects, it is possible to inspect the openings of the deposition mask 20 for defects even if the openings OP1 and OP2 of the deposition mask 20 have different shapes.

[0098] Subsequently, each of the opening groups GR1 to GR6 arranged in the inspection area IA is photographed (S40), and based on the photographed result, it is determined whether the result is within the critical range (S50). Therefore, it is determined whether the openings OP1 and OP2 arranged in the deposition mask 20 are defective (S51, S52).

[0099] Each of the aperture groups GR1 to GR6 arranged within the inspection area IA is photographed by the vision unit 120, and the aperture groups GR1 to GR6 are compared with each other. The process of comparing each of the aperture groups GR1 to GR6 with each other can be performed by comparing each of the images photographed for each of the aperture groups GR1 to GR6 with each other. Therefore, by comparing the areas of the openings OP1 and OP2 of each of the aperture groups GR1 to GR6, it is possible to find an aperture group that includes a defective opening among the aperture groups GR1 to GR6.

[0100] When vision unit 120 includes a CCD sensor and captures each of aperture groups GR1 to GR6, pixels of the CCD sensor may be arranged within apertures OP1 and OP2 of each of aperture groups GR1 to GR6 on the captured image. The pixels of the CCD sensor of vision unit 120 are arranged at regular intervals, and the areas of apertures OP1 and OP2 of each of aperture groups GR1 to GR6 can be compared based on the number of pixels of the CCD sensor arranged within apertures OP1 and OP2.

[0101] The pixels of the CCD sensor may be located within one end UE1, UE2 of each opening OP1, OP2 and / or within the other end BE1, BE2 of each opening OP1, OP2. That is, when determining whether the openings OP1, OP2 are defective, at least one of the pixels of the CCD sensor located within one end UE1, UE2 of each opening OP1, OP2 and the pixels of the CCD sensor located within the other end BE1, BE2 of each opening OP1, OP2 serves as the basis for determining whether the openings OP1, OP2 are defective.

[0102] Among the openings OP1, OP2 of each of the opening groups GR1 to GR6 arranged in the inspection area IA, the openings OP1, OP2 that are good may have a certain number of CCD sensor pixels within a certain range, while the openings OP1, OP2 that are bad may have a number of CCD sensor pixels that exceeds that range. That is, the openings OP1, OP2 of each of the opening groups GR1 to GR6 arranged in the inspection area IA can be compared for each opening group GR1 to GR6, and therefore, openings OP1, OP2 in which the number of CCD sensor pixels located is within a critical range can be determined to be good (normal), and openings OP1, OP2 in which the number of CCD sensor pixels located is beyond the critical range can be determined to be bad.

[0103] Furthermore, by comparing the shapes of the openings OP1 and OP2 of each of the opening groups GR1 to GR6, it is possible to find an opening group that includes a defective opening among the opening groups GR1 to GR6.

[0104] Pixels of the CCD sensor may be arranged along the edge shape of the openings OP1, OP2 of each of the opening groups GR1 to GR6 arranged in the inspection area IA. The length of each edge of the openings OP1, OP2 of each of the opening groups GR1 to GR6 can be compared based on the number of pixels of the CCD sensor arranged on each edge, and the shape of each opening OP1, OP2 of each of the opening groups GR1 to GR6 can be compared. The edge of the openings OP1, OP2 may be at least one of one side end UE1, UE2 and / or the other side end BE1, BE2 of the openings OP1, OP2.

[0105] For example, the lengths of the edges extending in the first direction DR1, the lengths of the edges extending in the second direction DR2, and / or the lengths of the edges extending in a direction inclined relative to the first direction DR1 and the second direction DR2 of the first opening OP1 and the second opening OP2 of each of the opening groups GR1 to GR6 can be compared. The shapes of the first opening OP1 and the second opening OP2 of each of the opening groups GR1 to GR6 can be compared based on these lengths, etc.

[0106] That is, when determining whether the openings OP1, OP2 are defective, the shapes of the openings OP1, OP2 of the opening groups GR1 to GR6 in the inspection area IA can be compared with each other between the opening groups GR1 to GR6. In this case, openings OP1, OP2 having shapes within the critical range can be determined to be non-defective (normal), and openings OP1, OP2 having shapes outside the critical range can be determined to be defective.

[0107] When comparing the openings OP1 and OP2 of each of the aperture groups GR1 to GR6, horizontal rotation of some of the aperture groups GR1 to GR6 may be taken into consideration. For example, some of the aperture groups GR2 and GR5 among the aperture groups GR1 to GR6 may be rotated 180 degrees horizontally from the shapes of the remaining aperture groups GR1, GR3, GR4, and GR6. When comparing the openings OP1 and OP2 of each of the aperture groups GR1 to GR6, the rotated aperture groups GR2 and GR5 may be rotated 180 degrees horizontally, and the openings OP1 and OP2 may be compared. In other words, the rotated aperture groups GR2 and GR5 may be rotated 180 degrees in the opposite direction to the rotation direction, and the openings OP1 and OP2 of each of the aperture groups GR1 to GR6 may be compared. Therefore, even if some of the aperture groups GR1 to GR6 are rotated horizontally by a certain angle, it is possible to more accurately determine whether the openings OP1 and OP2 of each of the aperture groups GR1 to GR6 are defective.

[0108] When comparing the areas and / or shapes of the openings OP1, OP2 of each of the opening groups GR1 to GR6, an inspector can first compare the areas and / or shapes of the openings OP1, OP2 of each of the opening groups GR1 to GR6 with the naked eye based on the images captured by the vision unit 120. A determination can be made as to whether or not there is a defect based on the comparison results. That is, the inspector can primarily use the naked eye to detect defective products that have different areas and / or shapes among the openings OP1, OP2 of adjacent opening groups GR1 to GR6. However, the present invention is not limited to the example shown here, and the process of detecting defective products with the inspector's naked eye can be omitted.

[0109] The above describes a case where openings OP1 and OP2 having different shapes are first grouped (S30), then the group is photographed and compared (S40). However, the order is not limited to the example shown here, and it is also possible to first photograph the inspection area IA (S40), and then group openings OP1 and OP2 having different shapes in the photographed image (S30), and then compare them to determine whether they are defective (S50).

[0110] Furthermore, to determine defective openings, the openings OP1 and OP2 of each of the opening groups GR1 to GR6 are compared with each other within the inspection area IA, but the method of determining defective openings is not limited to the example shown here, and the openings OP1 and OP2 of each of the opening groups GR1 to GR6 may also be compared with each other with a reference image generated from drawing data used when forming the deposition mask 20. In this case, the mask inspection method may further include the step of obtaining a reference image, and the arrangement (or placement) of the openings OP1 and OP2 of each of the opening groups GR1 to GR6 is substantially similar to the arrangement (or placement) of the openings included in the reference image.

[0111] Other embodiments will be described below. In the following embodiments, the description of the same configuration as the already described embodiments will be omitted or simplified, and the description will focus on the differences from the already described embodiments.

[0112] FIG. 8 is a plan view simply showing a mask inspection method according to another embodiment.

[0113] Referring to FIG. 8, the mask inspection method according to this embodiment differs from the embodiment of FIG. 7 in that each of the opening groups GR1_1, GR2_1, GR3_1, GR4_1, GR5_1, and GR6_1 has three openings OP1_1, OP2_1, and OP3_1 having different shapes.

[0114] Specifically, the deposition mask 20_1 according to this embodiment may include an inspection area IA_1, and a plurality of opening groups GR1_1, GR2_1, GR3_1, GR4_1, GR5_1, and GR6_1 may be arranged in the inspection area IA_1. Each of the opening groups GR1_1, GR2_1, GR3_1, GR4_1, GR5_1, and GR6_1 may include three openings OP1_1, OP2_1, and OP3_1 having different shapes.

[0115] The aperture groups GR1_1, GR2_1, GR3_1, GR4_1, GR5_1, and GR6_1 are repeatedly arranged not only inside but also outside the inspection area IA_1, and the openings OP1_1, OP2_1, and OP3_1 of the aperture groups GR1_1, GR2_1, GR3_1, GR4_1, GR5_1, and GR6_1 can be repeatedly arranged. The openings OP1_1, OP2_1, and OP3_1 can be arranged adjacent to each other.

[0116] In this case as well, even if the openings OP1_1, OP2_1, and OP3_1 arranged in the deposition mask 20_1 have different shapes on a plane, it is possible to inspect whether the deposition mask 20_1 is defective.

[0117] 9 is a schematic layout diagram showing a pixel array of a display device according to another embodiment of the present invention, and shows an example of a display device 400_1 that can be manufactured using the deposition mask 20_1 of FIG.

[0118] Referring to FIG. 9, the display device 400_1 includes a plurality of pixels PX. A pixel PX is a minimum unit of display that is repeated. To display full colors, each pixel PX may include a plurality of subpixels PXS1, PXS2, and PXS3 that emit different colors. For example, each pixel PX may include a first subpixel PXS1 that emits red light, a second subpixel PXS2 that emits blue light, and a third subpixel PXS3 that emits green light. Each pixel PX includes one first subpixel PXS_1, one second subpixel PXS_2, and one third subpixel PXS_3. The first subpixel PXS_1, the second subpixel PXS_2, and the third subpixel PXS_3 may have different shapes in a plan view. In this case, a common layer commonly disposed in the light-emitting devices (EMDs, see FIG. 5) of the subpixels PXS1, PXS2, and PXS3 may be stacked together.

[0119] FIG. 10 is a plan view simply showing a mask inspection method according to still another embodiment.

[0120] Referring to FIG. 10, the mask inspection method according to one embodiment differs from the embodiment of FIG. 7 in that each of the opening groups GR1_2, GR2_2, and GR3_2 includes openings OP1_2, OP2_2, OP4_2, and OP5_2 arranged in different regions.

[0121] Specifically, the deposition mask 20_2 according to one embodiment may include two regions AR1_2 and AR2_2 having different opening arrangement patterns. The first region AR1_2 may include first to third openings OP1_2, OP2_2, and OP3_2, which may have different shapes in a plan view. The second region AR2_2 may include fourth to sixth openings OP4_2, OP5_2, and OP6_2, which may have different shapes and / or sizes in a plan view. Furthermore, the first to third openings OP1_2, OP2_2, and OP3_2 may have different shapes and / or sizes from the fourth to sixth openings OP4_2, OP5_2, and OP6_2.

[0122] The arrangement pattern of the first to third openings OP1_2, OP2_2, and OP3_2 in the first region AR1_2 may be different from the arrangement pattern of the fourth to sixth openings OP4_2, OP5_2, and OP6_2 in the second region AR2_2. Furthermore, as will be described later, the first to third openings OP1_2, OP2_2, and OP3_2 in the first region AR1_2 may perform substantially the same functions as the fourth to sixth openings OP4_2, OP5_2, and OP6_2 in the second region AR2_2, respectively. That is, the first opening OP1_2 in the first region AR1_2 and the fourth opening OP4_2 in the second region AR2_2 may be used to form pixels that emit light of the same color (e.g., red) despite having different shapes and / or sizes. The second opening OP2_2 in the first region AR1_2 and the fifth opening OP5_2 in the second region AR2_2 can be used to form pixels that have different shapes and / or sizes but emit light of the same color (e.g., blue). The third opening OP3_2 in the first region AR1_2 and the sixth opening OP6_2 in the second region AR2_2 can be used to form pixels that have different shapes and / or sizes but emit light of the same color (e.g., green).

[0123] At the boundary between the first region AR1_2 and the second region AR2_2, the opening groups GR1_2, GR2_2, GR3_2 may include at least one of the first to third openings OP1_2, OP2_2, OP3_2 and at least one of the fourth to sixth openings OP4_2, OP5_2, OP6_2. For example, each of the opening groups GR1_2, GR2_2, GR3_2 may include the first opening OP1_2 and the second opening OP2_2 of the first region AR1_2 and the fourth opening OP4_2 and the fifth opening OP5_2 of the second region AR2_2 at the boundary.

[0124] In this case, the opening groups GR1_2, GR2_2, and GR3_2 are compared, and the openings OP1_2, OP2_2, OP4_2, and OP5_2 included in each opening group GR1_2, GR2_2, and GR3_2 can be inspected for defects. Furthermore, before or after the inspection, the first to third openings OP1_2, OP2_2, and OP3_2 in the first region AR1_2 and the fourth to sixth openings OP4_2, OP5_2, and OP6_2 in the second region AR2_2 can be inspected, respectively. The inspection methods for the first region AR1_2 and the second region AR2_2 can be similarly applied to the inspection methods described above.

[0125] Each of the opening groups GR1_2, GR2_2, and GR3_2, which are the minimum units of mask inspection, includes at least some of the openings OP1_2, OP2_2, OP3_2, OP4_2, OP5_2, and OP6_2 included in each of the regions AR1_2 and AR2_2 at the boundary between the regions AR1_2 and AR2_2. This allows the deposition mask 20_2 to be inspected for defects more precisely even if the deposition mask 20_2 includes a plurality of regions AR1_2 and AR2_2 having opening arrangement patterns different from each other. That is, some of the openings OP1_2, OP2_2, OP4_2, and OP5_2 adjacent to the boundary between the first region AR1_2 and the second region AR2_2 can be inspected for defects by the above-mentioned method even if they are not grouped in the inspection for the first region AR1_2 and the inspection for the second region AR2_2.

[0126] In this case, even if the openings OP1_2, OP2_2, OP3_2, OP4_2, OP5_2, and OP6_2 arranged in the deposition mask 20_2 have different shapes on a plane and include two areas where the arrangements of the openings OP1_2, OP2_2, OP3_2, OP4_2, OP5_2, and OP6_2 are different from each other, it is possible to inspect whether the deposition mask 20_2 is defective.

[0127] 11 is a schematic layout diagram showing a pixel array of a display device according to still another embodiment. FIG. 11 shows an example of a display device 400_2 that can be manufactured using the deposition mask 20_2 of FIG.

[0128] 11, the display device 400_2 is divided into a first display region and a second display region depending on whether it includes a light-transmitting portion TA. For example, the display device 400_2 may include a display-only region DPA_D as the first display region and a display-transmitting region DPA_T as the second display region. The display-only region DPA_D may correspond to the first region AR1_2 in FIG. 10, and the display-transmitting region DPA_T may correspond to the second region AR2_2 in FIG. 10.

[0129] Both the display-only area DPA_D and the display light-transmitting area DPA_T include multiple pixels PX_R, PX_B, and PX_G that include light-emitting areas, and display images by the light emitted by the light-emitting areas of each pixel PX_R, PX_B, and PX_G. The display light-transmitting area DPA_T further includes multiple light-transmitting portions TA in addition to the pixels PX_R, PX_B, and PX_G that include light-emitting areas. The display-only area DPA_D does not include the light-transmitting portions TA. The light-transmitting portions TA of the display light-transmitting area DPA_T are areas that do not emit light themselves, but rather transmit light in the thickness direction.

[0130] The light-transmitting portion TA of the display light-transmitting region DPA_T can be used for various purposes. For example, the light-transmitting portion TA of the display light-transmitting region DPA_T can be used as a passage for light sensing, without being limited to the example shown here. Although not shown in the drawings, a light-sensing member (not shown) can be disposed below the display device 400_2. The light-sensing member (not shown) is a device that receives light, acquires information, and performs a specific function. Examples of the light-sensing member include a camera including a photoelectric conversion element, an infrared proximity sensor, an iris recognition sensor, and a fingerprint sensor. Therefore, the display light-transmitting region DPA_T can function as a passage for allowing external light to reach the light-sensing member (not shown) while displaying videos and images.

[0131] Fig. 12 is a side view schematically showing a mask inspection apparatus according to yet another embodiment, and Fig. 13 is a flowchart showing a mask inspection method according to yet another embodiment.

[0132] Referring to Figures 12 and 13, the mask inspection apparatus 10_3 according to one embodiment differs from the embodiment of Figure 1 in that it further includes a foreign matter detection unit 143_3, and the mask inspection method according to one embodiment differs from the embodiments of Figures 6 to 7 in that it further includes a step (S60_3) of determining whether or not a foreign matter exists.

[0133] Specifically, the mask inspection apparatus 10_3 according to an embodiment may further include a foreign matter detector 143_3 that determines whether or not a foreign matter exists on the deposition mask 20. The presence or absence of a foreign matter may be determined by a control unit 140_3, and the control unit 140_3 may further include the foreign matter detector 143_3.

[0134] The step S60_3 of determining whether or not a foreign substance exists may be performed after the step S40 of photographing and comparing the aperture groups (GR1 to GR6, see FIG. 7). The presence or absence of a foreign substance can be determined based on image information of the aperture groups (GR1 to GR6, see FIG. 7) acquired via the vision unit 120. Although not limited to the example shown here, the presence or absence of a foreign substance can be determined by taking into account the light reflectance, surface roughness, or shape of each aperture group (GR1 to GR6, see FIG. 7).

[0135] If it is determined that a foreign substance is present in the step of determining whether or not a foreign substance is present (S60_3), the foreign substance can be removed (S61_3). The method of removing the foreign substance is not limited to the example shown here, but the foreign substance can be removed by, for example, cleaning. After the step of removing the foreign substance (S61_3), the opening groups (GR1 to GR6, see FIG. 7) can be photographed again and compared (S40).

[0136] If it is determined that no foreign matter is present in the step S60_3 of determining whether or not a foreign matter is present, it is determined whether or not the photographed results of each opening group (GR1 to GR6, see FIG. 7) are present within the critical range (S50).

[0137] In this case, even if the openings (OP1, OP2, see FIG. 7) arranged in the deposition mask 20 have different shapes on a plane, it is possible to inspect whether the deposition mask 20 is defective. Furthermore, by further inspecting whether there is a foreign substance, it is possible to reduce defects in the deposition mask 20.

[0138] Although the present invention has been described above with reference to the accompanying drawings, those skilled in the art will understand that the present invention may be embodied in other specific forms without departing from the spirit and essential features of the present invention. It should be understood that the above-described embodiment is illustrative in all respects and is not limiting. [Explanation of symbols]

[0139] OP opening 140 Control Unit GR Opening Group 141 Comparison Section 110 Support stand 142 Judgment Department 120 Vision Unit 143_3 Foreign object detection unit 121 Light-emitting member 150 Output section 122 Light receiving member 130 Data Processing Unit

Claims

1. preparing an evaporation mask including a plurality of first openings and a plurality of second openings, wherein each of the first openings has a different shape from each of the second openings in a plan view; designating a first group and a second group each including at least one of the first openings and at least one of the second openings; comparing the first group of images with the second group of images; determining whether the first group and the second group are defective based on a result of comparing the image of the first group with the image of the second group; an arrangement of the first openings and the second openings included in the first group may be the same as an arrangement of the first openings and the second openings included in the second group, or may be rotated by a predetermined angle in a horizontal direction with respect to an arrangement of the first openings and the second openings included in the second group; and comparing the image of the first group with the image of the second group includes comparing the image of the first group with the image of the second group, in which the first openings and the second openings included in the first group are rotated by the predetermined angle in the horizontal direction, only if the arrangement of the first openings and the second openings included in the first group is the same as that rotated by the predetermined angle in the horizontal direction with respect to the arrangement of the first openings and the second openings included in the second group.

2. 2. The mask inspection method of claim 1, further comprising, prior to comparing the first group and the second group, photographing the first group and the second group using a vision unit including a CCD sensor including a plurality of pixels to obtain an image of the first group and an image of the second group.

3. 2. The mask inspection method of claim 1, wherein comparing the first group of images with the second group of images includes comparing shapes of the first group with shapes of the second group.

4. further comprising photographing the first group and the second group using a vision unit including a CCD sensor including a plurality of pixels; 4. The mask inspection method according to claim 3, wherein comparing the shape of the first group with the shape of the second group includes comparing the shape of a portion of the pixels of the CCD sensor that is arranged in the first group with the shape of another portion of the pixels of the CCD sensor that is arranged in the second group.

5. 2. The mask inspection method of claim 1, wherein comparing the first group and the second group further comprises rotating one of the images of the first group and the images of the second group in a horizontal direction.

6. 1. A mask inspection apparatus for inspecting an evaporation mask including a plurality of first openings and a plurality of second openings, each having a shape different from each of the first openings on a plane, comprising: a support stand for supporting the deposition mask; a vision unit that is separated from the support stand and captures an image of the deposition mask; a control unit that determines whether or not the first opening and the second opening are defective based on the image acquired by the vision unit, the control unit designates a first group and a second group each including at least one of the plurality of first openings and at least one of the plurality of second openings, and compares a first image obtained by capturing the first group with a second image obtained by capturing the second group; an arrangement of the first openings and the second openings included in the first group may be the same as an arrangement of the first openings and the second openings included in the second group, or may be rotated by a predetermined angle in a horizontal direction with respect to an arrangement of the first openings and the second openings included in the second group; a mask inspection apparatus, wherein comparing the first image with the second image includes comparing the image of the first group with the image of the second group in which the first openings and the second openings included in the first group are rotated by the predetermined angle in the horizontal direction only if the arrangement of the first openings and the second openings included in the first group is the same as the arrangement of the first openings and the second openings included in the second group rotated by the predetermined angle in the horizontal direction.

7. 7. The mask inspection apparatus according to claim 6, wherein the vision unit further includes a light irradiation member that emits light toward the deposition mask, and a light receiving member that receives at least a portion of the light emitted from the light irradiation member and includes a CCD sensor having a plurality of pixels.

8. 7. The mask inspection apparatus according to claim 6, wherein the control unit compares the planar shape of the first group with the planar shape of the second group.

9. 7. The mask inspection apparatus according to claim 6, wherein the control unit further includes a foreign matter detection unit that determines whether or not a foreign matter is present on the deposition mask.

10. 7. The mask inspection apparatus of claim 6, further comprising an output unit that outputs information on whether or not the mask is defective as determined by the control unit.

11. The mask inspection apparatus of claim 10 , further comprising a data processing unit that processes image information captured by the vision unit and provides the image information to the control unit.

Images