Test device for display devices

Abstract

A test apparatus as a stress measurement sample for a display device includes a sample substrate and a reflector disposed on the sample substrate. The sample substrate includes a portion of a mother substrate used to manufacture the display device, and the display device includes another portion of the mother substrate.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0070356, filed on May 29, 2024, and all benefits derived therefrom, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments relate to a testing apparatus for a display device and a method for manufacturing a display device, the method including testing the display device using the testing apparatus. The display device may include light-emitting diodes, such as organic light-emitting diodes, as display elements. Background Technology

[0004] Display devices include light-emitting diodes (LEDs) as display elements and can provide images or videos through the LEDs. Display devices can be manufactured by forming several layers on a substrate. Recently, display devices have become more flexible, allowing some areas to be bent. To manufacture flexible display devices, a flexible substrate can be disposed on a rigid glass substrate, and several layers can be disposed on the flexible substrate. In this case, the glass substrate can be pulled in one or more directions to flatten the surfaces of the flexible substrate and the layers disposed thereon.

[0005] Therefore, curvature can occur on a stretched glass substrate, and similar curvature can occur on flexible substrates and several layers thereon. To reduce or prevent this curvature, apparatus and methods are needed for measuring and evaluating the stress formed within the glass substrate. Summary of the Invention

[0006] In related technologies, a silicon wafer sample is placed on a glass substrate, various layers are placed on it, and then the stress in the silicon wafer sample is measured. However, this method has several problems. First, the physical properties of the silicon wafer sample are different from those of the glass substrate, making it difficult to directly apply the stress measurement results to the glass substrate. Second, because the silicon wafer is placed on the glass substrate and various layers are placed on it, protrusions can occur due to the thickness of the silicon wafer, and these protrusions can affect the stress measurement results.

[0007] The embodiments include a testing apparatus for a display device, specifically a stress measurement sample. The embodiments also include a method for manufacturing a display device.

[0008] Additional features will be set forth in part in the following description and will be apparent in part from the description or may be learned by practicing the embodiments presented in this disclosure.

[0009] In one embodiment of this disclosure, a testing apparatus for a display device may include a sample substrate and a reflector disposed on the sample substrate. The sample substrate includes a portion of a mother substrate used for manufacturing the display device.

[0010] In one embodiment, the reflector may include a plurality of reflective patterns spaced apart from each other.

[0011] In one embodiment, the multiple reflective patterns may include multiple concentric closed loops.

[0012] In one embodiment, the thickness of the sample substrate may be less than the thickness of the parent substrate.

[0013] In one embodiment, the testing apparatus for the display device may further include measurement marks on a sample substrate.

[0014] In one embodiment, the testing apparatus for the display device may further include a protective film disposed on the reflector.

[0015] In one embodiment, the protective film may be separable from the reflector.

[0016] In one embodiment, the mother substrate may include glass.

[0017] In one embodiment of this disclosure, the testing apparatus for a display device may include a sample substrate and a plurality of sample layers disposed on the sample substrate. The sample substrate includes a portion of a mother substrate for manufacturing the display device, and the plurality of sample layers on the sample substrate include portions of layers disposed on the mother substrate for manufacturing the display device.

[0018] In one embodiment, the mother substrate may include a first region and a second region surrounding the first region. The first region is the area in which a display device is formed, and the sample substrate includes a portion of the second region of the mother substrate.

[0019] In one embodiment of this disclosure, a method for manufacturing a display device may include forming multiple layers on a mother substrate, obtaining a sample by cutting a portion of the mother substrate, and performing stress testing on the sample.

[0020] In one embodiment, the method of manufacturing a display device may further include separating a plurality of layers disposed on a mother substrate as a whole from the mother substrate.

[0021] In one embodiment, the method of manufacturing a display device may further include depositing a reflective layer on a mother substrate or sample.

[0022] In one embodiment, the method of manufacturing a display device may further include setting measurement marks on a sample.

[0023] In one embodiment, the method of manufacturing a display device may further include setting a protective film on a sample.

[0024] In one embodiment, the protective film may be removed before stress testing.

[0025] In one embodiment, the method of manufacturing a display device may further include reducing the thickness of the sample.

[0026] In one embodiment, the sample may be circular in a plan view.

[0027] In one embodiment, when cutting the mother substrate, multiple layers can be cut together, and the sample may include a portion of multiple layers.

[0028] In one embodiment, the mother substrate may include a first region and a second region at least partially surrounding the first region, and the first region may include an area in which a display device is formed, and a sample may be obtained from the second region. Attached Figure Description

[0029] The above and other features and advantages of the exemplary embodiments of this disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0030] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5A , Figure 5B and Figure 6 A perspective view illustrating an embodiment of the operation of a method for manufacturing a display device;

[0031] Figure 7A , Figure 7B and Figure 7C A schematic plan view of an embodiment of the test sample;

[0032] Figure 8A , Figure 8B , Figure 8C and Figure 8D A schematic plan view of an embodiment of the test sample;

[0033] Figure 9A and Figure 9B A schematic plan view of an embodiment of the test sample;

[0034] Figure 10A and Figure 10B A schematic perspective view of an embodiment of the test sample;

[0035] Figure 11 , Figure 12 and Figure 13 A perspective view illustrating an embodiment of the operation of a method for manufacturing a display device;

[0036] Figure 14A plan view of an embodiment of a display panel manufactured by a method for manufacturing a display device; and

[0037] Figure 15 This is a cross-sectional view of an embodiment of a display panel manufactured by a method for manufacturing a display device. Detailed Implementation

[0038] Because this disclosure allows for various modifications and numerous embodiments, exemplary embodiments will be illustrated in the accompanying drawings and described in the detailed description. The effects and features of this disclosure, as well as methods of implementing them, will be illustrated with reference to the embodiments described in detail below with reference to the accompanying drawings. However, this disclosure is not limited to the following embodiments and can be embodied in various forms.

[0039] In the following description, embodiments will be described in detail with reference to the accompanying drawings, wherein the same or corresponding elements are always indicated by the same reference numerals and repeated descriptions thereof are omitted.

[0040] Although terms such as "first," "second," etc., can be used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

[0041] As used herein, the singular forms “a”, “an”, and “the” also include the plural forms, unless the context clearly indicates otherwise.

[0042] It will be understood that the terms “comprising,” “including,” and “having” are intended to indicate the presence of a feature or element described in the specification and are not intended to exclude the possibility that one or more other features or elements may be present or added.

[0043] It will be further understood that when a layer, area, or component is referred to as being "on" another layer, area, or component, it may be directly on the other layer, area, or component, or indirectly on the other layer, area, or component, with an intermediate layer, area, or component existing in between.

[0044] For ease of explanation, the dimensions of the components in the accompanying drawings may be enlarged or reduced. For example, the dimensions and thicknesses of any components illustrated in the drawings are for ease of explanation, and this disclosure is not limited thereto.

[0045] When exemplary embodiments can be implemented differently, the specific processing order may differ from the described order. For example, two consecutively described processes may be performed substantially simultaneously, or they may be performed in the reverse order of the description.

[0046] "A and / or B" is used in this document to select only A, select only B, or select both A and B. "At least one of A and B" is used to select only A, select only B, or select both A and B.

[0047] In the following embodiments, when layers, areas, components, etc., are connected to each other, they can be directly connected to each other and / or indirectly connected to each other, and other layers, areas, and components can be inserted between them. For example, when layers, areas, components, etc., are electrically connected to each other in the specification, they can be directly electrically connected to each other, and / or indirectly electrically connected to other layers, areas, and components, and other layers, areas, and components can be inserted between them.

[0048] The x-axis, y-axis, and z-axis are not limited to the three axes of a Cartesian coordinate system, and can be interpreted in a broader sense, including the Cartesian coordinate system. For example, the x-axis, y-axis, and z-axis can be perpendicular to each other, but can also refer to different directions that are not orthogonal to each other.

[0049] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5A , Figure 5B and Figure 6 A perspective view illustrating one embodiment of the operation of a method for manufacturing a display device.

[0050] refer to Figure 1 A mother substrate 1 can be prepared. In this disclosure, the mother substrate 1 may be a substrate providing a base for manufacturing a display device. In one embodiment, the display device may include several layers, and the layers may be disposed on the mother substrate 1, the layers including inorganic materials, organic materials and / or metallic materials. In one embodiment, the mother substrate 1 may include glass.

[0051] In one embodiment, the display device layer may be disposed on the mother substrate 1, and then separated from the mother substrate 1 and sent to subsequent processes. In this case, the mother substrate 1 may not be included in the display device.

[0052] In one embodiment, the layers of the display device may be disposed on the mother substrate 1 and then cut together with the mother substrate 1 to form a single display device. In this case, it is understood that multiple display devices may be manufactured from a single mother substrate 1. In this case, a portion of the mother substrate 1 may be included in the display device.

[0053] In the following text, for ease of explanation, the case in which the layers included in the display device are separated from the mother substrate 1 and sent to subsequent processes is shown and described in detail, that is, the case in which the mother substrate 1 is not included in the display device.

[0054] In one embodiment, the mother substrate 1 may have a substantially quadrilateral shape in a plan view, such as a rectangular shape. In one embodiment, the mother substrate 1 may have a quadrilateral shape, such as a rectangular shape having a long side extending along the x-axis and a short side extending along the y-axis. In one embodiment, the mother substrate 1 may have a quadrilateral shape, such as a rectangular shape having a short side extending along the x-axis and a long side extending along the y-axis. In one embodiment, the mother substrate 1 may have a shape other than a quadrilateral shape such as a rectangle in a plan view. In one embodiment, for example, the mother substrate 1 may have other shapes in a plan view, such as circular, elliptical, polygonal, or irregular shapes.

[0055] In one embodiment, the mother substrate 1 may include a first region A1 and a second region A2. In one embodiment, the first region A1 may have a quadrilateral shape in a plan view, such as a rectangular shape. In one embodiment, the first region A1 may have a quadrilateral shape, for example, a rectangular shape having a short side extending along the x-axis and a long side extending along the y-axis. In one embodiment, a plurality of first regions A1 may be provided. In one embodiment, the plurality of first regions A1 may be spaced apart from each other within the mother substrate 1. In one embodiment, the second region A2 may at least partially surround the first region A1. In one embodiment, the remaining area of ​​the mother substrate 1 other than the plurality of first regions A1 may be defined as the second region A2. In one embodiment, the first region A1 may define a boundary along which a panel layer is cut to manufacture a display device.

[0056] refer to Figure 2 The reflective layer 2 and the panel layer 3 can be disposed on the mother substrate 1.

[0057] In one embodiment, the reflective layer 2 may be disposed on the upper surface of the mother substrate 1 to cover the entire mother substrate 1. In another embodiment, the reflective layer 2 may be disposed on the mother substrate 1 with a predetermined pattern. The predetermined pattern of the reflective layer 2 will be described in detail later. The reflective layer 2 may include a material that reflects light.

[0058] In one embodiment, panel layer 3 may be disposed on the upper surface of reflective layer 2 to cover the entire reflective layer 2. In one embodiment, panel layer 3 may include multiple layers. In one embodiment, panel layer 3 may include light-emitting diodes (LEDs) as display elements and thin-film transistors (TFTs) for driving the LEDs. In one embodiment, panel layer 3 may include multiple insulating layers, in which LEDs and TFTs are disposed. In one embodiment, panel layer 3 may include a thin-film encapsulation layer to cover and protect the LEDs. In one embodiment, a portion of the multiple layers included in panel layer 3 may not cover the entire reflective layer 2 and may be pre-patterned. In one embodiment, reference... Figure 1A portion of panel layer 3 may be disposed in the first region A1, and may not be disposed in the second region A2. In one embodiment, for example, the light-emitting diodes of panel layer 3 may be disposed only in the first region A1. In one embodiment, panel layer 3 may include regions that transmit light and regions that do not transmit light. In one embodiment, panel layer 3 may be a display device in a manufacturing process or a part of a display device in a manufacturing process.

[0059] The process of setting panel layer 3 may include several processes, such as deposition, inkjet printing, and / or etching. Panel layer 3 may be configured to resemble the upper surface of the mother substrate 1 and / or reflective layer 2. In other words, when the upper surface of the mother substrate 1 and / or reflective layer 2 has curvature, curvature may also be present in panel layer 3. This can lead to a degradation in the quality of the display device. Therefore, in the process of setting panel layer 3, the upper surface of the mother substrate 1 and / or reflective layer 2 needs to be kept flat. To keep the upper surface of the mother substrate 1 and / or reflective layer 2 flat, the mother substrate 1 or reflective layer may be pulled in a predetermined direction. In one embodiment, for example, the mother substrate 1 and / or reflective layer 2 may be pulled along the x-axis and / or y-axis, and the upper surface of the mother substrate 1 and / or reflective layer 2, for example, the surface facing the +z direction, may be planarized. Panel layer 3 may be disposed on the stretched mother substrate 1 and / or reflective layer 2.

[0060] In this case, during the process of pulling the mother substrate 1 to planarize it, stress can be applied to the mother substrate 1, and deformation (e.g., bending) can occur in the mother substrate 1. Deformation can also occur in the reflective layer 2 and the panel layer 3.

[0061] refer to Figure 3 The panel layer 3 can be separated from the mother substrate 1 and the reflective layer 2.

[0062] As described above, panel layer 3 can be a display device in the manufacturing process. Accordingly, panel layer 3 can be transferred to subsequent processes (e.g., cutting processes) and can perform the next operation of manufacturing the display device.

[0063] As described above, the deformation that occurs during the process of pulling the mother substrate 1 will occur in the panel layer 3, the reflective layer 2, and the mother substrate 1. Even after the panel layer 3 separates from the mother substrate 1, the deformation may still exist. When the mother substrate 1 and the reflective layer 2 are tested to determine the strain in the mother substrate 1, the stress in the mother substrate 1 can be determined, and the strain in the panel layer 3 can also be determined. The testing apparatus (e.g., test sample) and testing methods used to test the mother substrate 1 will be described in detail below.

[0064] refer to Figure 4A cutting line CL is marked on the mother substrate 1 and the reflective layer 2. The cutting line CL can be an imaginary line marked on the mother substrate 1 and the reflective layer 2 to obtain the sample. In one embodiment, the cutting line CL can be physically marked on the reflective layer 2. The cutting line CL can define the shape of the sample. Figure 4 In the illustration, the cutting line CL is shown as substantially circular, but this disclosure is not limited thereto. The cutting line CL may have other shapes. In one embodiment, multiple cutting lines CL may be marked.

[0065] refer to Figure 4 , Figure 5A and Figure 5B The mother substrate 1 and the reflective layer 2 can be cut along the cutting line CL to obtain multiple test sample SPCs.

[0066] The test sample SPC may include a sample substrate 10 and a reflector 20. In one embodiment, the sample substrate 10 may be a portion of a mother substrate 1. In one embodiment, for example, the sample substrate 10 may be a portion of a mother substrate 1 obtained by cutting the mother substrate 1 along a cut line CL. In one embodiment, the reflector 20 may be a portion of a reflective layer 2. In one embodiment, for example, the reflector 20 may be a portion of a reflective layer 2 obtained by cutting the reflective layer 2 along a cut line CL. In this disclosure, the reflector 20 included in the test sample SPC after cutting may also be referred to as a sample layer.

[0067] When comparing in the embodiments Figure 5A The test sample SPC shown in the figure Figure 5B When the test sample SPC shown in the figure is used, the thickness of the sample substrate 10 in each test sample SPC may be different. Figure 5A The thickness of the sample substrate 10 of the test sample SPC shown is defined as the first thickness t1, and Figure 5B The thickness of the sample substrate 10 of the test sample SPC shown is defined as the second thickness t2. In one embodiment, the first thickness t1 may be greater than the second thickness t2. In other words, Figure 5B The thickness of the sample substrate 10 of the test sample SPC shown in the figure (i.e., the second thickness t2) may be less than the thickness of the mother substrate 1 (i.e., the first thickness t1). In one embodiment, by... Figure 5A A thinning process is performed on the sample substrate 10 shown in the figure, which can achieve Figure 5B The sample substrate 10 shown in the figure.

[0068] In one embodiment, the mother substrate 1 and the reflective layer 2 can be cut along the cutting line CL to achieve... Figure 5A The test sample SPC is shown in the figure. In one embodiment, the mother substrate 1 and the reflective layer 2 can be cut along the cleaving line CL, and the sample substrate 10 can be thinned to obtain... Figure 5BThe test sample SPC is shown in the figure. In one embodiment, the mother substrate 1 can be thinned first, and the thinned mother substrate 1 and the reflective layer 2 can be cut to obtain... Figure 5B The test sample SPC is shown below. For ease of explanation, it will be shown and described in the following text. Figure 5A The test sample SPC.

[0069] refer to Figure 6 The stress in the SPC test sample can be measured.

[0070] To measure the stress in a test sample SPC, light can be directed at the test sample SPC, the strain of the test sample SPC can be measured using an optical path, and the measured strain can be used to determine the stress in the test sample SPC. In one embodiment, the test sample SPC may be a reflective test sample, and light may be reflected from the surface of the test sample SPC (e.g., the surface of reflector 20).

[0071] First, the first light L1 and the second light L2 can be directed to two points on the test sample SPC. In one embodiment, for example, the first light L1 and the second light L2 can be directed to two points on the reflector 20 of the test sample SPC. The points on which the first light L1 is incident (or reflected) on the test sample SPC (e.g., reflector 20) and the second light L2 are incident (or reflected) on the test sample SPC (e.g., reflector 20) can be spaced apart by a distance LL. The first light L1 and the second light L2 can be spaced apart by a first distance d1.

[0072] The first light L1 and the second light L2 can be reflected from the surface of the reflector 20. The angle of incidence and the angle of reflection are the same. The reflection path or reflected light of the second light L2 when the test sample SPC is not deformed is shown as a dashed line L2. The reflection path or reflected light of the second light L2 when the test sample SPC is deformed is shown as a solid line L2'. In this case, the test sample SPC may deform in some parts. In one embodiment, for example, the test sample SPC may bend in the +z direction at approximately the strain angle δθ.

[0073] The detector DET can be positioned on the reflection paths of the first light L1 and the second light L2. In one embodiment, the detector DET can be a photodetector. The reflected light from the first light L1 and the reflected light from the second light L2 when the test sample SPC is undeformed (i.e., L2) can each reach the detector DET, and the arrival points of the two reflected lights on the detector DET can be spaced apart by a second distance d2. The reflected light from the first light L1 and the reflected light from the second light L2 when the test sample SPC is deformed (i.e., L2') can each reach the detector DET, and the arrival points of the two reflected lights on the detector DET can be spaced apart by a third distance d3. The difference between the second distance d2 and the third distance d3 can be defined as the strain distance δd.

[0074] The strain in the test sample SPC can be obtained using the strain angle δθ and / or strain distance δd. In one embodiment, the strain angle δθ and / or strain distance δd can be the strain in the test sample SPC. The sample substrate 10 may have known physical properties, such as Young's modulus. Based on the known Young's modulus of the sample substrate 10 and the measured strain of the sample substrate 10, the stress applied to the sample substrate 10 can be calculated.

[0075] The strain in the test sample SPC obtained by this process can be applied not only to the reflector 20 or the sample substrate 10, but also to the mother substrate 1. Figure 2 ) and panel layer 3 ( Figure 2 Therefore, by measuring the strain (and stress) of the test sample SPC, the mother substrate 1 can be determined. Figure 2 ) and panel layer 3 ( Figure 2 The strain (and stress) in the sample SPC is used to determine the strain (and stress) of the display device during the manufacturing process. In other words, by measuring the strain (and stress) in the sample SPC, the strain (and stress) of the display device during the manufacturing process can be determined. The manufacturing conditions of the display device can be adjusted based on this information.

[0076] Figure 7A , Figure 7B and Figure 7C This is a schematic plan view of an embodiment of a test sample in some embodiments.

[0077] refer to Figure 7A The test sample SPC may have a quadrilateral shape in the planar diagram, such as a rectangle. In one embodiment, the test sample SPC may have a quadrilateral shape, for example, a rectangle having a long side extending along the x-axis and a short side extending along the y-axis. In one embodiment, the test sample SPC may have a quadrilateral shape, for example, a rectangle having a short side extending along the x-axis and a long side extending along the y-axis.

[0078] refer to Figure 7B The corners of the test sample SPC can be rounded. In one embodiment, the test sample SPC may have a long side extending along the x-axis and a short side extending along the y-axis, and the corners where the long and short sides intersect can be rounded. In one embodiment, the test sample SPC may have a short side extending along the x-axis and a long side extending along the y-axis, and the corners where the long and short sides intersect can be rounded.

[0079] refer to Figure 7C The test sample SPC may have the shape of a dog bone or a dumbbell. In one embodiment, for example, a portion of the long side of the test sample SPC extending along the x-axis may be concave along the y-axis. Accordingly, the length of the test sample SPC along the y-axis may vary along the x-axis. Figure 7CThe illustration shows a case where each edge and corner of the test sample SPC has an angle, but this disclosure is not limited thereto, and at least a portion of each edge and corner may be rounded.

[0080] Figure 8A , Figure 8B , Figure 8C and Figure 8D This is a schematic plan view of an embodiment of the test sample. Figures 8A to 8D In the embodiment shown, the reflector 20 of the test sample SPC may be disposed on the sample substrate 10, but may not cover the entire sample substrate 10. The reflector 20 of the test sample SPC may include multiple reflective patterns disposed on the sample substrate 10.

[0081] refer to Figure 8A The reflector 20 (e.g., a plurality of reflective patterns of the reflector 20) may include a plurality of strips extending along the y-axis. The strips may be spaced apart from each other along the x-axis. In one embodiment, the reflector 20 may include a plurality of strips extending along the x-axis, and the strips of the reflector 20 may be spaced apart from each other along the y-axis. Figure 8A An embodiment with five stripes is shown, but this disclosure is not necessarily limited to a predetermined number of stripes. In one embodiment, as... Figure 8A As shown, the stripe of reflector 20 may be spaced apart from the edge of sample substrate 10. In one embodiment, with Figure 8A Unlike the previous case, a portion of the stripe of the reflector 20 may overlap with the edge of the sample substrate 10.

[0082] refer to Figure 8A and Figure 6 The first beam L1 and the second beam L2 may be spaced apart along the x-axis and may point to different stripes. In an alternative embodiment, the first beam L1 and the second beam L2 may be spaced apart along the y-axis and may point to the same stripe.

[0083] refer to Figure 8B The reflector 20 (e.g., multiple reflective patterns of the reflector 20) may include multiple islands. The islands may be spaced apart from each other along the x-axis and / or y-axis. In one embodiment, the islands may be approximated as follows: Figure 8B The square shown in the image. Figure 8B An embodiment with 25 square islands is shown, but this disclosure is not necessarily limited to a predetermined shape or number of islands.

[0084] refer to Figure 8B and Figure 6In one embodiment, the first beam L1 and the second beam L2 may be spaced apart along the x-axis and may point to different islands. In another embodiment, the first beam L1 and the second beam L2 may be spaced apart along the y-axis and may point to different islands. In yet another embodiment, the first beam L1 and the second beam L2 may be spaced apart from each other and may point to the same island.

[0085] refer to Figure 8C The reflector 20 (e.g., a plurality of reflective patterns of the reflector 20) may include a plurality of circular closed loops. In one embodiment, the plurality of circular closed loops may be concentric. In one embodiment, the thickness (or linewidth) of the circular closed loops may vary. In one embodiment, the thickness of each circular closed loop may be proportional to its diameter. In one embodiment, for example, the thickness of the circular closed loop disposed on the outer side (e.g., near the edge of the sample substrate 10) may be greater than or equal to the thickness of the circular closed loop disposed on the inner side (e.g., near the center of the sample substrate 10). Figure 8C An embodiment with three circular closed loops is shown, but this disclosure is not necessarily limited to a predetermined number of circular closed loops.

[0086] refer to Figure 8C and Figure 6 In one embodiment, the first beam L1 and the second beam L2 may be spaced apart along the x-axis and may point to different circular closed loops. In another embodiment, the first beam L1 and the second beam L2 may be spaced apart along the y-axis and may be guided to different circular closed loops. In yet another embodiment, the first beam L1 and the second beam L2 may be spaced apart along diagonal directions of the x-axis and y-axis and may point to different circular closed loops.

[0087] refer to Figure 8D The reflector 20 (e.g., multiple reflective patterns of the reflector 20) may include multiple square closed loops or frames. In one embodiment, the multiple frames may be concentric. In one embodiment, the thickness (or linewidth) of the frames may vary. In one embodiment, for example, the thickness of the frames disposed on the outer side (e.g., near the edge of the sample substrate 10) may be greater than or equal to the thickness of the frames disposed on the inner side (e.g., near the center of the sample substrate 10). In one embodiment, a portion of the frames disposed on the outer side may overlap with the edge of the sample substrate 10. In one embodiment, only a portion of the frames disposed on the outer side may be disposed on the sample substrate 10.

[0088] refer to Figure 8D and Figure 6In one embodiment, the first light beam L1 and the second light beam L2 may be spaced apart along the x-axis and may point to different frames. In another embodiment, the first light beam L1 and the second light beam L2 may be spaced apart along the y-axis and may point to different frames. In yet another embodiment, the first light beam L1 and the second light beam L2 may be spaced apart along diagonal directions of the x-axis and y-axis and may point to different frames.

[0089] Figure 9A and Figure 9B A schematic plan view of an embodiment of the test sample.

[0090] refer to Figure 9A and Figure 9B Measurement markers MK can be marked on the test sample SPC, for example, on reflector 20. Measurement markers MK may include axes and grid lines marked at regular intervals. In one embodiment, as... Figure 9A As shown, the measurement marker MK may include numbers. In one embodiment, such as... Figure 9B As shown, the measurement mark MK may not include numbers.

[0091] refer to Figure 9A , Figure 9B and Figure 6 In one embodiment, the distance (i.e., LL) between the incident (or reflected) points of the first light L1 and the second light L2 can be determined based on the measurement mark MK.

[0092] refer to Figure 9B and Figure 8C In one embodiment, due to strain in the test sample SPC, the reflector 20, comprising multiple circular closed loops, is deformable, and the multiple circular closed loops may no longer be concentric, such as... Figure 9B As shown in the diagram. In this case, the direction and distance of the circular closed-loop deformation of the reflector 20 can be measured using the measuring marker MK, and the strain in the test sample SPC can be measured without performing [further steps]. Figure 6 The method (or reflection test) shown in the diagram is used to determine this. In this case, the degree of deformation (e.g., strain) can be determined quickly.

[0093] Figure 10A and Figure 10B A schematic perspective view of an embodiment of the test sample.

[0094] refer to Figure 10A and Figure 10B The test sample SPC may further include a protective film 40. In this disclosure, the protective film 40 included in the test sample SPC after cutting may also be referred to as a sample layer. In one embodiment, the protective film 40 may be disposed on the reflector 20. In one embodiment, the protective film 40 may include an organic insulating material or an inorganic insulating material. In one embodiment, the protective film 40 may help protect the reflector 20 and / or the sample substrate 10 by preventing oxidation.

[0095] In one embodiment, the protective film 40 may be disposed on the upper surface of the reflector 20 and may cover the upper surface of the reflector 20. In one embodiment, such as Figure 10A As shown, the protective film 40 may only cover the upper surface of the reflector 20 (e.g., the surface facing the +z direction). In one embodiment, the protective film 40 may cover the upper and side surfaces of the reflector 20 and the side surface of the sample substrate 10, such as... Figure 10B As shown in the figure. In one embodiment, the protective film 40 can cover the entire test sample SPC by also covering the bottom surface of the sample substrate 10 (e.g., the surface facing the -z direction).

[0096] In one embodiment, the protective film 40 may be removable. In one embodiment, for example, during performance Figure 6 Prior to the method (or reflection test) shown, the protective film 40 may be removed and the upper surface of the reflector 20 may be exposed. In one embodiment, the protective film 40 may be reattached to the reflector 20.

[0097] In one embodiment, the protective film 40 may be transparent. In this case, when performing... Figure 6 When performing the method (or reflection test) shown, the protective film 40 may not be removed. Because the protective film 40 may be transparent, light (e.g., first light L1 and second light L2) may pass through the protective film 40 and reach the reflector 20.

[0098] refer to Figure 7A , Figure 7B and Figure 7C The described embodiments and references Figure 8A , Figure 8B , Figure 8C and Figure 8D The described implementation methods and references Figure 9A and Figure 9B The described embodiments and references Figure 10A and Figure 10B The described embodiments can be combined with each other in various ways.

[0099] Figure 11 , Figure 12 and Figure 13 A perspective view illustrating one embodiment of the operation of a method for manufacturing a display device.

[0100] refer to Figure 11 Panel layer 3 can be placed on the mother substrate 1. In this case, reflective layer 2 may not be disposed between the mother substrate 1 and panel layer 3. Figure 1 Similar to the embodiment shown, the mother substrate 1 and the panel layer 3 may each include a first region A1 and a second region A2. Additionally, with... Figure 4Similar to the embodiment shown, the mother substrate 1 and the panel layer 3 may each include a cutting line CL. In one embodiment, the cutting line CL may be disposed in a second region A2.

[0101] refer to Figure 11 and Figure 12 The mother substrate 1 and panel layer 3 can be cut along the boundary of the first region A1 and the cutting line CL.

[0102] In one embodiment, a portion of the panel layer 3 cut along the boundary of the first region A1 may be a display panel 31. In other words, a portion of the panel layer 3 cut along the boundary of the first region A1 may be a display device 31 in the manufacturing process. In one embodiment, the display panel 31 may be transferred to subsequent processes, and the next step of manufacturing a display device may be performed on the display panel 31. In one embodiment, a portion of the mother substrate 1 cut along the boundary of the first region A1, i.e., the remaining substrate 11, may be discarded.

[0103] In one embodiment, a portion of the mother substrate 1 and panel layer 3 cut along the cleaving line CL may be a test sample SPC. In one embodiment, a portion of the mother substrate 1 cut along the cleaving line CL may be a sample substrate 10. In one embodiment, a portion of the panel layer 3 cut along the cleaving line CL may be a transmissive portion 30. In this disclosure, for example, the transmissive portion 30 included in the cut test sample SPC may also be referred to as a sample layer.

[0104] In other words, the mother substrate 1 and the panel layer 3 can each be divided into a first region A1 and a second region A2, and the display panel 31 can be obtained by cutting along the boundary of the first region A1. In addition, the test sample SPC can be obtained by cutting along the cutting line CL in the region where the display panel 31 is not obtained (i.e., the second region A2).

[0105] refer to Figure 13 The stress in the SPC test sample can be measured.

[0106] To measure the stress in a test sample SPC, light can be directed at the test sample SPC. The strain of the test sample SPC can be measured using the optical path, and the measured strain can be used to determine the stress of the test sample SPC. Figure 13 The principle of the stress measurement method shown in the figure can be compared with... Figure 6 The principle of the stress measurement method shown is similar. However, in this embodiment, the test sample SPC can be a transmissive test sample, and light can pass through the test sample SPC. For example, in one embodiment, light can pass through the transmissive portion 30 and the sample substrate 10.

[0107] First, the first light L1 and the second light L2 can be directed to two points on the test sample SPC. In this case, the first light L1 and the second light L2 can be directed to two points on the transmission portion 30 of the test sample SPC. The point where the first light L1 is incident on the test sample SPC (e.g., the transmission portion 30) and the point where the second light L2 is incident on the test sample SPC (e.g., the transmission portion 30) can be spaced apart by a distance LL. The first light L1 and the second light L2 can be spaced apart by a first distance d1.

[0108] For ease of illustration and explanation, reflected light is not shown. Each of the first light L1 and the second light L2 is refractable when it enters the transmission section 30 from the surrounding environment (e.g., vacuum). In this case, the refractive index of the transmission section 30 may be greater than the refractive index of the surrounding environment (e.g., vacuum). Each of the first light L1 and the second light L2 is refractable when it passes through the transmission section 30 and enters the sample substrate 10. Figure 13 The illustration shows a case where the refractive index of the sample substrate 10 is greater than that of the transmission portion 30, but this disclosure is not limited to this. The first light L1 and the second light L2 can pass through the sample substrate 10 and enter the surrounding environment (e.g., vacuum). In this case, the refractive index of the sample substrate 10 may be greater than the refractive index of the surrounding environment (e.g., vacuum).

[0109] The transmission path or transmitted light of the second beam L2 when the test sample SPC is undeformed is shown as a dashed line L2. The transmission path or transmitted light of the second beam L2 when the test sample SPC is deformed is shown as a solid line L2'. In this case, the test sample SPC may deform in some parts. In one embodiment, for example, the test sample SPC may bend in the +z direction at approximately a strain angle δθ.

[0110] The detector DET can be positioned on the transmission paths of the first light L1 and the second light L2, which extend beyond the test sample SPC. In one embodiment, the detector DET can be a photodetector. The transmitted light from the first light L1 and the transmitted light from the second light L2 when the test sample SPC is undeformed (i.e., L2) can each reach the detector DET, and the arrival points of the two beams can be spaced apart by a second distance d2. The transmitted light from the first light L1 and the transmitted light from the second light L2 when the test sample SPC is deformed (i.e., L2') can each reach the detector DET, and the arrival points of the two transmitted lights on the detector DET can be spaced apart by a third distance d3. The difference between the second distance d2 and the third distance d3 can be defined as the strain distance δd.

[0111] The strain of the test sample SPC can be obtained using the strain angle δθ and / or strain distance δd. In one embodiment, the strain angle δθ and / or strain distance δd can be the strain in the test sample SPC. The sample substrate 10 and / or the transmission portion 30 may have known physical properties, such as Young's modulus. The stress applied to the sample substrate 10 and / or the transmission portion 30 can be calculated based on the known Young's modulus and the measured strain.

[0112] The strain in the test sample SPC obtained by this process can be applied not only to the transmission portion 30 or the sample substrate 10, but also to the mother substrate 1. Figure 11 ), Panel layer 3 ( Figure 11 ) and display panel 31 ( Figure 12 Therefore, by measuring the strain (and stress) of the test sample SPC, the display panel 31 can be determined. Figure 12 The strain (and stress) in the test sample (SPC) can be measured. In other words, by measuring the strain (and stress) in the test sample (SPC), the strain (and stress) of the display device during the manufacturing process can be predicted. The manufacturing conditions of the display device can be adjusted based on this information.

[0113] Figure 14 This is a plan view of an embodiment of a display panel manufactured by a method for manufacturing a display device. Figure 15 This is a cross-sectional view of an embodiment of a display panel manufactured by a method for manufacturing a display device.

[0114] For example, Figure 14 and Figure 15 The display panel 31 can be Figure 3 Panel layer 3 or Figure 12 The display panel is appropriately cut. In one embodiment, the display panel 31 may be a display device in the manufacturing process. In one embodiment, the display panel 31 may be part of a display device. In one embodiment, the display panel 31 may be the display device itself.

[0115] refer to Figure 14 and Figure 15 The display panel 31 may include a display area DA and a non-display area NDA outside the display area DA. Light-emitting diodes (LEDs) may be disposed in the display area DA, and power wiring (not shown) may be disposed in the non-display area NDA. Additionally, pad portions (not shown) may be disposed in the non-display area. Multiple deposited material patterns may be arranged in the display area DA.

[0116] The substrate 310 may include polyimide. In one embodiment, the substrate 310 may be flexible, bendable, and / or rollable. A thin-film transistor (TFT) may be disposed on the substrate 310, a first via layer 317-1 and a second via layer 317-2 may be configured to cover the TFT, and a light-emitting diode (LED) may be disposed thereon.

[0117] A buffer layer 311, comprising organic and / or inorganic compounds, may be further disposed on the substrate 310. The buffer layer 311 may include SiO₂. x (x≥1) and / or SiN x (x≥1) or composed of.

[0118] An active layer 312, patterned according to a predetermined design, may be disposed on a buffer layer 311, and then the active layer 312 may be covered by a gate insulating layer 313. The active layer 312 may include a source region and a drain region, and may further include a channel region between the source and drain regions. The active layer 312 may be formed comprising or composed of various materials. In one embodiment, the active layer 312 may include or be composed of inorganic semiconductor materials, such as amorphous silicon or crystalline silicon. In one embodiment, the active layer 312 may include or be composed of oxide semiconductors. In one embodiment, the active layer 312 may include or be composed of organic semiconductor materials.

[0119] A gate electrode 314 corresponding to the active layer 312 and an interlayer insulating layer 315 covering the gate electrode 314 may be disposed on the gate insulating layer 313. Contact holes are formed in the interlayer insulating layer 315 and the gate insulating layer 313. Then, a source electrode 316-1 and a drain electrode 316-2 may be disposed on the interlayer insulating layer 315 to contact the source region and drain region of the active layer 312, respectively.

[0120] The first via layer 317-1 and the second via layer 317-2 may be disposed on the thin-film transistor (TFT), and the pixel electrode 319 of the light-emitting diode (LED) may be disposed on the second via layer 317-2. The first via layer 317-1 may cover the source electrode 316-1 and the drain electrode 316-2. The second via layer 317-2 may cover the first via layer 317-1. The first via layer 317-1 and the second via layer 317-2 may comprise inorganic and / or organic materials, and may be formed as planarization layers, such that their upper surfaces are flat regardless of the curvature of the underlying layer or can be bent along the curvature of the underlying layer.

[0121] A via may be formed in the first via layer 317-1, and at least a portion of the contact metal CM may be disposed in the via of the first via layer 317-1. A via may also be formed in the second via layer 317-2, and a portion of the pixel electrode 319 may be disposed in the via of the second via layer 317-2. The pixel electrode 319 contacts the drain 316-2 of the thin-film transistor TFT through the vias defined in the first via layer 317-1 and the second via layer 317-2. In one embodiment, for example, the contact metal CM may contact the drain 316-2 through the via defined in the first via layer 317-1, and the pixel electrode 319 may contact the contact metal CM through the via defined in the second via layer 317-2, thus being connected to the drain electrode 316-2.

[0122] A pixel defining layer 318 may be disposed on the pixel electrode 319 and the second via layer 317-2. A portion of the pixel defining layer 318 may be opened to expose a portion (e.g., the central portion) of the pixel electrode 319.

[0123] Intermediate layer 320 and opposing electrode 321 may be disposed on pixel electrode 319. In one embodiment, opposing electrode 321 may be disposed on intermediate layer 320 and pixel defining layer 318. Pixel electrode 319 may serve as an anode, and opposing electrode 321 may serve as a cathode. In one embodiment, the polarities of pixel electrode 319 and opposing electrode 321 may be reversed. Pixel electrode 319 and opposing electrode 321 are insulated from each other through intermediate layer 320. Pixel electrode 319 and opposing electrode 321 apply voltages of different polarities to intermediate layer 320 to cause the emitting layer to emit light.

[0124] Intermediate layer 320 may include an emitter layer. In another embodiment, intermediate layer 320 may include an organic emitter layer, and in addition to the organic emitter layer, may further include at least one of a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer. This disclosure is not limited thereto, and intermediate layer 320 may include an emitter layer, and may further include various other functional layers (not shown).

[0125] A unit pixel comprises multiple sub-pixels, and the multiple sub-pixels can emit light of various colors. In one embodiment, the multiple sub-pixels may include sub-pixels configured to emit red, green, and blue light respectively, or may include sub-pixels (not shown) configured to emit red, green, blue, and white light respectively. A sub-pixel may include an intermediate layer 320.

[0126] The thin-film encapsulation layer (TFE) can be configured to cover a light-emitting diode (LED). The TFE may include multiple inorganic layers, or it may include both inorganic and organic layers. In one embodiment, for example, the TFE may include a first inorganic encapsulation layer 322, an organic encapsulation layer 323, and a second inorganic encapsulation layer 324. The first inorganic encapsulation layer 322 and / or the second inorganic encapsulation layer 324 may be a single layer or a stacked layer comprising oxide or nitride materials. In one embodiment, for example, the first inorganic encapsulation layer 322 and / or the second inorganic encapsulation layer 324 may include silicon nitride (SiN). x ), aluminum oxide (Al2O3), silicon oxide (SiO2) x At least one of polyethylene terephthalate (PET) and titanium dioxide (TiO2). The organic encapsulation layer 323 may include a polymer and may be a single layer or a stacked layer including at least one of polyethylene terephthalate, polyimide, polycarbonate, epoxy resin, polyethylene and polyacrylate.

[0127] In one embodiment, the testing apparatus for a display includes a test sample, i.e., a stress measurement sample, obtained from a mother substrate during the manufacturing process of the display device. Because the stress measurement sample is obtained from a mother substrate used to manufacture the display device, it accurately provides information about the physical characteristics and shape (e.g., curvature) of the display device. Furthermore, since multiple such stress measurement samples can be obtained from the mother substrate, the stress measurement process can be repeated multiple times using multiple stress measurement samples. Additionally, economic benefits are achieved because it eliminates the need to place individual components (e.g., silicon wafers) on the mother substrate. In one embodiment, a method for manufacturing a display device is provided, including a process of testing the display device using the aforementioned stress measurement sample. However, this disclosure is not limited thereto.

[0128] Although embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made therein. Therefore, the scope of this disclosure should be defined by the spirit and scope of the following claims.

Claims

1. A testing apparatus for display devices, characterized in that, The testing apparatus includes: Sample substrate; and A reflector is disposed on the sample substrate; The sample substrate includes a portion of the mother substrate, and the display device includes another portion of the mother substrate.

2. The testing apparatus according to claim 1, characterized in that, The reflector comprises multiple reflective patterns spaced apart from each other.

3. The testing apparatus according to claim 2, characterized in that, The multiple reflection patterns include multiple concentric closed loops.

4. The testing apparatus according to claim 1, characterized in that, The thickness of the sample substrate is less than the thickness of the parent substrate.

5. The testing apparatus according to claim 1, characterized in that, The testing apparatus further includes: Measurement marks are set on the sample substrate.

6. The testing apparatus according to claim 1, characterized in that, The testing apparatus further includes: A protective film is applied to the reflector.

7. The testing apparatus according to claim 6, characterized in that, The protective film and the reflector are separable.

8. The testing apparatus according to claim 1, characterized in that, The mother substrate includes a first region and a second region that at least partially surrounds the first region. The first region is the region formed therein by the display device, and The sample substrate includes a portion of the second region of the parent substrate.

9. A testing apparatus for a display device, characterized in that, The testing apparatus includes: Sample substrate; and Multiple sample layers are disposed on the sample substrate; The sample substrate includes a portion of the mother substrate, and the display device includes another portion of the mother substrate. The plurality of sample layers disposed on the sample substrate include a portion of the layers disposed on the mother substrate, and the display device includes another portion of the layers disposed on the mother substrate.

10. The testing apparatus according to claim 9, characterized in that, The mother substrate includes a first region and a second region that at least partially surrounds the first region, the first region being the region in which the display device is formed, and the sample substrate includes a portion of the second region of the mother substrate.

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