Patent Publication Number: US-2022212459-A1

Title: Peeling device and peeling method using the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to, and the benefit of, Korean Patent Application No. 10-2021-0001722, filed on Jan. 7, 2021, the contents of which are hereby incorporated by reference in its entirety. 
     BACKGROUND 
     1. Field 
     The present disclosure relates to a peeling device that peels off a base layer from a film, and a peeling method using the same. 
     2. Description of the Related Art 
     Various types of display devices are used to provide image information. In recent years, flexible display devices, including a flexible display panel that is foldable or bendable, are being used. Different from a rigid display device, the flexible display device is able to be folded, rolled, or bent. Because the shape of the flexible display device is changed in various ways, the flexible display device is able to be carried regardless of its original screen size. 
     The flexible display device may suitably have a window that covers the display panel to protect the display panel from external impacts without interfering with the folding or bending operation. Accordingly, it may be suitable to develop a flexible window that has high durability against external impacts, and that is able to perform the folding or bending operation. 
     SUMMARY 
     The present disclosure provides a peeling device capable of peeling off a flexible base layer from an adhesive layer. The present disclosure also provides a peeling method using such a peeling device. 
     Embodiments of the present disclosure provide a peeling device including a peeling tank containing a first solution therein, a support portion on which a stack structure including a base layer extending in a first direction and a film coupled with the base layer is disposed, the support portion being disposed in the peeling tank and an adsorption device for adsorbing the base layer thereon to peel off the base layer from the film, the adsorption device including an adsorption portion for adsorbing the base layer, and a moving portion coupled with the adsorption portion for moving the adsorption portion to allow the base layer to be bent to a second direction crossing the first direction and to be peeled off from the film. 
     The first solution may include water having a temperature from about 50° C. to about 90° C. 
     The base layer may include an upper surface to be adsorbed to the adsorption portion, and a lower surface coupled with the film, wherein the adsorption device is configured to peel the lower surface of the base layer off of the film. 
     The peeling device may further include a first nozzle, wherein the first nozzle faces a peeling area of the lower surface when the base layer is bent to the second direction by the adsorption device and spray a second solution to the peeling area of the lower surface and the film, and the second solution includes a same material as the first solution. 
     The peeling device may further include a second nozzle, wherein the second nozzle sprays a third solution to the upper surface, and the third solution includes a same material as the first solution. 
     The base layer may include a first base layer, and a second base layer, wherein the film includes an adhesive film between the first and second base layers to attach the first base layer to the second base layer, and wherein the adsorption portion is configured to be adsorbed to the second base layer. 
     The peeling device may further include a grip device that grips the film to remove the film from the peeling tank. 
     The moving portion may be configured to move the adsorption portion with the second base layer adsorbed thereto to a second position from a first position such that the base layer is peeled off from the film before moving the adsorption portion to allow the second base layer to be bent to the second direction. 
     The second direction may be substantially perpendicular to the first direction. 
     The base layer may include a thin film glass substrate. 
     The adsorption portion may include a plurality of adsorption pads configured to be adsorbed to the base layer, and a connection portion connecting the moving portion to the adsorption pads, wherein the base layer includes a first area at a center portion of the base layer, a second area around the first area, and adsorption points to be adsorbed to the adsorption pads in the second area. 
     Embodiments of the present disclosure provide a peeling method using a peeling device. The peeling method includes locating a stack structure including a base layer extending in a first direction, and a film coupled with the base layer, on a support portion in a peeling tank containing a first solution, and adsorbing the base layer using an adsorption device to peel off the base layer from the film, the peeling off of the base layer including adsorbing an adsorption portion to the base layer, and moving the adsorption portion using a moving portion to allow the base layer to be bent to a second direction crossing the first direction and to be peeled off from the film. 
     The first solution may include water having a temperature from about 50° C. to about 90° C. 
     The base layer may include an upper surface to be adsorbed to the adsorption portion, and a lower surface coupled with the film, wherein the method further includes peeling the lower surface of the base layer off of the film. 
     The peeling method may further include spraying a second solution to a peeling area of the lower surface and the film through a first nozzle facing the peeling area of the lower surface when the base layer is bent, the second solution including a same material as the first solution. 
     The peeling method may further include spraying a third solution to the upper surface through a second nozzle, the third solution including a same material as the first solution. 
     The base layer may include a first base layer, and a second base layer, wherein the film includes an adhesive film between the first and second base layers to attach the first base layer to the second base layer. 
     The peeling method may further include gripping the film using a grip device to remove the film from the peeling tank, wherein the second base layer is adsorbed to the adsorption portion in the adsorbing of the adsorption portion to the base layer, and wherein the second base layer is peeled off of the film in the peeling off of the base layer from the film. 
     The peeling off of the base layer from the film may include moving the adsorption portion to a second position from a first position. 
     The base layer may include a thin film glass substrate. 
     According to the above, in the stack structure including the flexible base layers and the film coupled to the base layers, the base layer is peeled off from the film using the peeling device. When the base layer is peeled off from the film using the peeling device, damage to the base layer may be reduced. Accordingly, the reliability of the peeling process for peeling the base layer from the film, and the efficiency of the process, are improved. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects of the present disclosure will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein: 
         FIG. 1A  is a perspective view showing a display device in an unfolded state according to some embodiments of the present disclosure; 
         FIG. 1B  is a perspective view showing the display device of  FIG. 1A  in the midst of a folding process; 
         FIG. 2  is a cross-sectional view taken along the line I-I′ shown in  FIG. 1A ; 
         FIG. 3  is a cross-sectional view showing a stack structure of base layers and a film according to some embodiments of the present disclosure; 
         FIG. 4  is a view showing a process of locating a stack structure on a support portion according to some embodiments of the present disclosure; 
         FIG. 5A  is a view showing a process of adsorbing a second base layer onto an adsorption device according to some embodiments of the present disclosure; 
         FIG. 5B  is a plan view of a second base layer to show adsorption points according to some embodiments of the present disclosure; 
         FIG. 6  is a view showing a process of peeling a first base layer from a film according to some embodiments of the present disclosure; 
         FIG. 7A  is a view showing a process of moving an adsorption portion to allow a second base layer to be bent to a third direction according to some embodiments of the present disclosure; 
         FIG. 7B  is an enlarged view showing a portion of the peeling device corresponding to an area AA′ of  FIG. 7A  to explain first to third nozzles; 
         FIG. 8  is a view showing a process of taking a second base layer out of a peeling tank according to some embodiments of the present disclosure; 
         FIG. 9  is a view showing a process of removing a film from a peeling tank using a grip device according to some embodiments of the present disclosure; 
         FIG. 10  is a flowchart showing a peeling method of the peeling device according to some embodiments of the present disclosure; and 
         FIG. 11  is a flowchart showing a process of peeling a base layer from a film and a process of spraying second and third solutions through first and second nozzles according to some embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of some embodiments of the present disclosure and methods of accomplishing the same may be understood more readily by reference to the detailed description of embodiments and the accompanying drawings. Hereinafter, embodiments will be described in more detail with reference to the accompanying drawings. The described embodiments, however, may be embodied in various different forms, and should not be construed as being limited to only the illustrated embodiments herein. Rather, these embodiments are provided as examples so that this disclosure will be thorough and complete, and will fully convey the aspects of the present disclosure to those skilled in the art. Accordingly, processes, elements, and techniques that are not necessary to those having ordinary skill in the art for a complete understanding of the aspects of the present disclosure may not be described. 
     Unless otherwise noted, like reference numerals, characters, or combinations thereof denote like elements throughout the attached drawings and the written description, and thus, descriptions thereof will not be repeated. Further, parts that are not related to, or that are irrelevant to, the description of the embodiments might not be shown to make the description clear. 
     Various embodiments are described herein with reference to sectional illustrations that are schematic illustrations of embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Further, specific structural or functional descriptions disclosed herein are merely illustrative for the purpose of describing embodiments according to the concept of the present disclosure. Thus, embodiments disclosed herein should not be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. Additionally, as those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present disclosure. 
     In the detailed description, for the purposes of explanation, numerous specific details are set forth to provide a thorough understanding of various embodiments. It is apparent, however, that various embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various embodiments. 
     Spatially relative terms, such as “beneath,” “below,” “lower,” “under,” “above,” “upper,” and the like, may be used herein for ease of explanation to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or in operation, in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” or “under” other elements or features would then be oriented “above” the other elements or features. Thus, the example terms “below” and “under” can encompass both an orientation of above and below. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should be interpreted accordingly. Similarly, when a first part is described as being arranged “on” a second part, this indicates that the first part is arranged at an upper side or a lower side of the second part without the limitation to the upper side thereof on the basis of the gravity direction. 
     Further, in this specification, the phrase “on a plane,” or “plan view,” means viewing a target portion from the top, and the phrase “on a cross-section” means viewing a cross-section formed by vertically cutting a target portion from the side. 
     It will be understood that when an element, layer, region, or component is referred to as being “formed on,” “on,” “connected to,” or “coupled to” another element, layer, region, or component, it can be directly formed on, on, connected to, or coupled to the other element, layer, region, or component, or indirectly formed on, on, connected to, or coupled to the other element, layer, region, or component such that one or more intervening elements, layers, regions, or components may be present. For example, when a layer, region, or component is referred to as being “electrically connected” or “electrically coupled” to another layer, region, or component, it can be directly electrically connected or coupled to the other layer, region, and/or component or intervening layers, regions, or components may be present. However, “directly connected/directly coupled” refers to one component directly connecting or coupling another component without an intermediate component. Meanwhile, other expressions describing relationships between components such as “between,” “immediately between” or “adjacent to” and “directly adjacent to” may be construed similarly. In addition, it will also be understood that when an element or layer is referred to as being “between” two elements or layers, it can be the only element or layer between the two elements or layers, or one or more intervening elements or layers may also be present. 
     As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, the expression such as “A and/or B” may include A, B, or A and B. 
     It will be understood that, although the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section described below could be termed a second element, component, region, layer or section, without departing from the spirit and scope of the present disclosure. The description of an element as a “first” element may not require or imply the presence of a second element or other elements. The terms “first”, “second”, etc. may also be used herein to differentiate different categories or sets of elements. For conciseness, the terms “first”, “second”, etc. may represent “first-category (or first-set)”, “second-category (or second-set)”, etc., respectively. 
     In the examples, the x-axis, the y-axis, and/or the z-axis are not limited to three axes of a rectangular coordinate system, and may be interpreted in a broader sense. For example, the x-axis, the y-axis, and the z-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. The same applies for first, second, and/or third directions. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “have,” “having,” “includes,” and “including,” when used in this specification, specify the presence of the stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     As used herein, the term “substantially,” “about,” “approximately,” and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent deviations in measured or calculated values that would be recognized by those of ordinary skill in the art. “About” or “approximately,” as used herein, is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” may mean within one or more standard deviations, or within ±30%, 20%, 10%, 5% of the stated value. Further, the use of “may” when describing embodiments of the present disclosure refers to “one or more embodiments of the present disclosure.” 
     When one or more embodiments may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. 
     Also, any numerical range disclosed and/or recited herein is intended to include all sub-ranges of the same numerical precision subsumed within the recited range. For example, a range of “1.0 to 10.0” is intended to include all subranges between (and including) the recited minimum value of 1.0 and the recited maximum value of 10.0, that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein, and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, Applicant reserves the right to amend this specification, including the claims, to expressly recite any sub-range subsumed within the ranges expressly recited herein. All such ranges are intended to be inherently described in this specification such that amending to expressly recite any such subranges would comply with the requirements of 35 U.S.C. § 112(a) and 35 U.S.C. § 132(a). 
     The electronic or electric devices and/or any other relevant devices or components according to embodiments of the present disclosure described herein may be implemented utilizing any suitable hardware, firmware (e.g., an application-specific integrated circuit), software, or a combination of software, firmware, and hardware, to process data or digital signals. For example, the various components of these devices may be formed on one integrated circuit (IC) chip or on separate IC chips. Further, the various components of these devices may be implemented on a flexible printed circuit film, a tape carrier package (TCP), a printed circuit board (PCB), or formed on one substrate. Circuit hardware may include, for example, application specific integrated circuits (ASICs), general purpose or special purpose central processing units (CPUs) that is configured to execute instructions stored in a non-transitory storage medium, digital signal processors (DSPs), graphics processing units (GPUs), and programmable logic devices such as field programmable gate arrays (FPGAs). 
     Further, the various components of these devices may be a process or thread, running on one or more processors, in one or more computing devices, executing computer program instructions and interacting with other system components for performing the various functionalities described herein. The computer program instructions are stored in a memory which may be implemented in a computing device using a standard memory device, such as, for example, a random access memory (RAM). The computer program instructions may also be stored in other non-transitory computer readable media such as, for example, a CD-ROM, flash drive, or the like. Also, a person of skill in the art should recognize that the functionality of various computing devices may be combined or integrated into a single computing device, or the functionality of a particular computing device may be distributed across one or more other computing devices without departing from the spirit and scope of the embodiments of the present disclosure. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present specification, and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein. 
       FIG. 1A  is a perspective view showing a display device DD in an unfolded state according to some embodiments of the present disclosure, and  FIG. 1B  is a perspective view showing the display device DD shown in  FIG. 1A  in the midst of a folding process. 
     Referring to  FIG. 1A , the display device DD may be a device that is activated in response to an electrical signal. The display device DD may include various embodiments. For example, the display device DD may include a tablet computer, a notebook computer, a computer, a smart television, and the like. In some embodiments, a foldable smartphone will be described as a representative example of the display device DD. 
     The display device DD may have a rectangular shape defined by short sides extending in a first direction DR 1 , and long sides extending in a second direction DR 2  crossing the first direction DR 1 . The second direction DR 2  may be substantially perpendicular to the first direction DR 1 . However, the shape of the display device DD should not be limited thereto or thereby, and the display device DD may have a variety of shapes. 
     The display device DD may display an image IM through a first display surface FS, which is substantially parallel to each of the first direction DR 1  and the second direction DR 2 . The image IM may be displayed toward a third direction DR 3 . The first display surface FS through which the image IM is displayed may correspond to a front surface of the display device DD. The image IM may include a still image and may include a video.  FIG. 1A  shows an internet search box and a clock widget as a representative example of the image IM. 
     In some embodiments, front (or upper) and rear (or lower) surfaces of each member of the display device DD may be defined with respect to a direction in which the image IM is displayed. The front and rear surfaces may be opposite to each other with respect to the third direction DR 3 , and a normal line direction of each of the front and rear surfaces may be substantially parallel to the third direction DR 3 . 
     A separation distance in the third direction DR 3  between the front surface and the rear surface may correspond to a thickness, or a height, in the third direction DR 3  of the display device DD. Meanwhile, directions indicated by the first, second, and third directions DR 1 , DR 2 , and DR 3  are relative to each other, and may be changed to other directions. 
     The display device DD may sense an external input applied thereto from the outside. The external input may include inputs of various forms provided from the outside of the display device DD. For example, the external input may include external inputs in proximity to, or approaching close to, the display device DD at a distance (e.g., a predetermined distance, which may correspond to a hovering input) as well as a touch input by a user&#39;s body (e.g., by a hand of a user). In addition, the external input may include various forms, such as force, pressure, temperature, or light. 
     The display device DD according to some embodiments may include the first display surface FS and a second display surface RS. The first display surface FS may include an active area F-AA, a peripheral area F-NAA, and an electronic module area EMA. The second display surface RS may be opposite to at least a portion of the first display surface FS. That is, the second display surface RS may be defined as a portion of the rear surface of the display device DD. 
     The active area F-AA may be activated in response to the electrical signal. The image IM may be displayed through the active area F-AA, and various external inputs may be sensed through the active area F-AA. The peripheral area F-NAA may be defined as being adjacent to the active area F-AA. The peripheral area F-NAA may have a color (e.g., a predetermined color). The peripheral area F-NAA may surround the active area F-AA. Accordingly, the active area F-AA may have a shape that is substantially defined by the peripheral area F-NAA, however, this is merely one example. In other embodiments, the peripheral area F-NAA may be defined to be adjacent to only one side of the active area F-AA, or may be omitted. The display device DD according to some embodiments may include active areas of various shapes, and should not be particularly limited. 
     Various electronic modules may be located in the electronic module area EMA. As an example, a corresponding electronic module may include at least one of a camera, a speaker, an optical sensor, and/or a thermal sensor. The electronic module area EMA may sense an external subject through the first and/or second display surfaces FS and RS, and/or may provide a sound signal, such as a voice, to the outside through the first and/or second display surfaces FS and RS. In addition, the electronic module may include a plurality of components, and the electronic module should not be limited to any particular embodiments. 
     The electronic module area EMA may be surrounded by the active area F-AA and the peripheral area F-NAA, however, the electronic module area EMA should not be limited thereto or thereby. The electronic module area EMA may be defined in the active area F-AA, and the electronic module area EMA should not be particularly limited. 
     The display device DD according to some embodiments may include at least one folding area FA 1 , and a plurality of non-folding areas NFA 1  and NFA 2  extending from the folding area FA 1 . The non-folding areas NFA 1  and NFA 2  may be spaced apart from each other with the folding area FA 1  interposed therebetween. 
     Referring to  FIG. 1B , the display device DD may include a folding axis AX 1  that is imaginary, and that extends in the second direction DR 2 . The folding axis AX 1  may extend in the second direction DR 2  on the first display surface FS. That is, the folding axis AX 1  may extend along a major axis of the display device DD. 
     According to some embodiments, the non-folding areas NFA 1  and NFA 2  may be located to be adjacent to the folding area FA 1  with the folding area FA 1  interposed therebetween. For example, a first non-folding area NFA 1  may be located adjacent to one side of the folding area FA 1  in the first direction DR 1 , and a second non-folding area NFA 2  may be located adjacent to the other side of the folding area FA 1  in the first direction DR 1 . 
     The display device DD may be folded about the folding axis AX 1  to be in an in-folding state where one area (e.g., a first area) of the first display surface FS, which overlaps the first non-folding area NFA 1 , faces the other area (e.g., a second area) of the first display surface FS, which overlaps the second non-folding area NFA 2 . However, the present disclosure should not be limited to the in-folding state. The display device DD may be folded about the folding axis AX 1  to be in an out-folding state where one area of the second display surface RS, which overlaps the first non-folding area NFA 1 , faces the other area of the second display surface RS, which overlaps the second non-folding area NFA 2 . 
       FIG. 2  is a cross-sectional view taken along the line I-I′ shown in  FIG. 1A . 
     Referring to  FIG. 2 , the display device DD may include a display module DM, an adhesive film AF, and a window WM. The display module DM may include a display panel DP and an input sensor ISP. 
     According to some embodiments, the display panel DP may be a light-emitting type display panel, however, the display panel DP should not be particularly limited. For instance, the display panel DP may be an organic light emitting display panel. 
     The input sensor ISP may be located directly on the display panel DP. According to some embodiments, the input sensor ISP may be formed on the display panel DP through successive processes. That is, in the case where the input sensor 
     ISP is located directly on the display panel DP, an inner adhesive film may be omitted from between the input sensor ISP and the display panel DP. However, in other embodiments, the inner adhesive film may be located between the input sensor ISP and the display panel DP. In this case, the input sensor ISP is not manufactured together with the display panel DP through the successive processes. That is, the input sensor ISP may be fixed to an upper surface of the display panel DP by the inner adhesive film after being manufactured through a separate process from the display panel DP. 
     The display panel DP may generate the image, and the input sensor ISP may obtain coordinate information on the external input (e.g., a touch event). The display module DM may be flexible. Accordingly, the display panel DP and the input sensor ISP may be rolled, folded or unfolded with respect to the folding axis AX 1 . 
     The window WM may be located on the display module DM. The window WM may include an optically transparent insulating material. Therefore, the image generated by the display module DM may be easily viewed by the user through the window WM. The window WM may transmit the image from the display module DM, and may substantially simultaneously buffer external impacts to reduce or prevent the likelihood of damage to the display module DM, or of causing malfunctioning of the display module DM, due to the external impacts. The external impacts indicate external force represented by pressure or stress, which causes defects in the display module DM. 
     The window WM may include a flexible material. Accordingly, the window WM may be folded or unfolded with respect to the folding axis AX 1 . That is, a shape of the window WM may be changed when a shape of the display module DM is changed. 
     The window WM may include a base layer BS (refer to  FIG. 3 ). The base layer BS may include a flexible glass substrate or a synthetic resin film. When the base layer BS includes the flexible glass substrate, the glass substrate may have a thickness that is equal to or smaller than about 80 micrometers. Accordingly, the glass substrate may be referred to as a thin film glass substrate. As an example, the base layer BS may have a thickness of about 30 micrometers, however, the thickness of the base layer BS should not be limited thereto or thereby. When the base layer BS includes the synthetic resin film, the base layer BS may include a polyimide (PI) film or a polyethylene terephthalate (PET) film. When the base layer BS includes the synthetic resin film, the base layer BS may have a thickness of about 50 micrometers. The base layer BS may have a single-layer or multi-layer structure. Hereinafter, the base layer BS will be described as the thin film glass substrate. 
     The display module DM may be coupled to the base layer BS by the adhesive film AF. As an example, the adhesive film AF may include an optically clear adhesive film (OCA). However, the adhesive film AF should not be limited thereto or thereby, and the adhesive film AF may include a conventional adhesive. For example, the adhesive film AF may include an optically clear resin (OCR) or a pressure sensitive adhesive (PSA) film. 
       FIG. 3  is a cross-sectional view showing a stack structure LM of base layers and a film(s) according to some embodiments of the present disclosure. 
     Referring to  FIG. 3 , the stack structure LM may include flexible base layers BS extending in the first direction DR 1  and films FL located between respective ones of the base layers BS. The base layers BS and the films FL may be stacked in the third direction DR 3 . 
     Among the base layers BS, two base layers BS adjacent to each other may be coupled with each other by one film FL located between the two base layers BS. 
     The film FL may include an optically clear adhesive (OCA) film. As an example, one film FL located between two base layers BS adjacent to each other may be cured at a room temperature, and thus, the two base layers BS may be coupled with each other. 
     One base layer BS may be peeled off from the stack structure LM using a peeling device PD described later, and then, the one base layer BS may be manufactured as the window WM (refer to  FIG. 2 ) employed in the display device DD (refer to  FIG. 1A ). The stack structure LM may be formed by cutting a stacked mother substrate, which is formed by coupling a plurality of mother substrates stacked with a film interposed therebetween, to a cell size (a size corresponding to the display device). In a case where the stack structure LM is formed by cutting the stacked mother substrate, a peeling process to peel off the film FL from the base layer BS is suitable. However, a work efficiency of the manufacturing process for the base layer BS may be improved as compared with a method of forming the base layer BS, which has a size corresponding to the cell size, by cutting one mother substrate. 
     The stack structure LM may further include dummy base layers. The dummy base layers may be provided to protect base layers respectively located at uppermost and lowermost positions among the base layers BS. The process of peeling off the base layer BS from the film FL using the peeling device PD shown in  FIGS. 4 to 8  may be carried out after the dummy base layers are removed from the stack structure LM. 
       FIG. 4  is a view showing a process of locating the stack structure LM on a support portion SPT according to some embodiments of the present disclosure. 
     Referring to  FIG. 4 , the peeling device PD may include a peeling tank PT with a first solution SL 1 , and the support portion SPT supporting the stack structure LM, in the peeling tank PT. Hereinafter, for the convenience of explanation, the stack structure LM will be described as a structure that includes two base layers (hereinafter, referred to as a first base layer BS 1  and a second base layer BS 2 ) and the film FL located between the first and second base layers BS 1  and BS 2  to couple the first base layer BS 1  to the second base layer BS 2  to each other. However, the number of the base layers included in the stack structure LM should not be particularly limited. 
     The peeling device PD may further include an adsorption device ADD that adsorbs (e.g., clings to) the second base layer BS 2  that is to be peeled off among the first and second base layers BS 1  and BS 2  included in the stack structure LM. 
     As an example, the first solution SL 1  may be a solution that does not exert influences on physical and chemical properties of the first and second base layers BS 1  and BS 2 . As an example, the first solution SL 1  may include water. The first solution SL 1  may maintain an appropriate temperature to lower a cohesive strength of materials constituting the film FL. When the cohesive strength of the materials constituting the film FL is lowered, an adhesion of the film FL may be lowered. Accordingly, the first and second base layers BS 1  and BS 2  may be easily peeled off from the film FL. As an example, the temperature of the first solution SL 1  may be within a range from about 50° C. to about 90° C. 
     The support portion SPT may include a support stage SPT_ 1  and a moving stage SPT_ 2 . 
     The stack structure LM may be located on the support stage SPT_ 1 . The moving stage SPT_ 2  may connect the peeling tank PT to the support stage SPT_ 1 . The moving stage SPT_ 2  may move the support stage SPT_ 1  in the third direction DR 3  or in a direction that is opposite to the third direction DR 3 . The operation of the moving stage SPT_ 2  will be described in detail with reference to  FIGS. 6 to 9 . 
     The adsorption device ADD may include an adsorption portion ADP that adsorbs the second base layer BS 2  and a moving portion MVP that is coupled with the adsorption portion ADP to move the adsorption portion ADP. 
     The adsorption portion ADP may include a plurality of adsorption pads SP that may be adsorbed to the second base layer BS 2 , and a connection portion CNP that connects the moving portion MVP to the adsorption pads SP. As an example, the adsorption portion ADP may allow the adsorption pads SP to be adsorbed to the second base layer BS 2  by vacuuming a space between the adsorption pads SP and the second base layer BS 2 . 
     The moving portion MVP may include a first moving portion MVP_ 1 , a second moving portion MVP_ 2 , and a third moving portion MVP_ 3 . In a case where the first, second, and third moving portions MVP_ 1 , MVP_ 2 , and MVP_ 3  move, the adsorption portion ADP coupled with the moving portion MVP may move together with the first, second, and third moving portions MVP_ 1 , MVP_ 2 , and MVP_ 3 . As an example, the moving portion MVP may be coupled with the adsorption portion ADP, and may move the adsorption portion ADP such that the second base layer BS 2  adsorbed to the adsorption portion ADP is bent toward the third direction DR 3  crossing the first direction DR 1 , and thus, the second base layer BS 2  may be peeled off from the film FL. In detail, the first moving portion MVP_ 1  may move in the first direction DR 1  or in a direction that is opposite to the first direction DR 1  to move the adsorption portion ADP in the first direction DR 1  or in the direction that is opposite to the first direction DR 1 . The second moving portion MVP_ 2  may move in the third direction DR 3  or in the direction that is opposite to the third direction DR 3  to move the adsorption portion ADP in the third direction DR 3  or in the direction that is opposite to the third direction DR 3 . 
     The third moving portion MVP_ 3  may include a first sub-moving portion MVP_ 3   a,  a second sub-moving portion MVP_ 3   b,  and a third sub-moving portion MVP_ 3   c.  The first sub-moving portion MVP_ 3   a  may connect the second and third sub-moving portions MVP_ 3   b  and MVP_ 3   c.  The second sub-moving portion MVP_ 3   b  may connect the first sub-moving portion MVP_ 3   a  and the second moving portion MVP_ 2 . The third sub-moving portion MVP_ 3   c  may connect the adsorption portion ADP and the first sub-moving portion MVP_ 3   a.  The second and third sub-moving portions MVP_ 3   b  and MVP_ 3   c  may extend in the first direction DR 1  or in the third direction DR 3 . The first sub-moving portion MVP_ 3   a  may rotate the third sub-moving portion MVP_ 3   c.  As an example, the first sub-moving portion MVP_ 3   a  may rotate the third sub-moving portion MVP_ 3   c  in a counter-clockwise direction. However, the rotation direction of the third sub-moving portion MVP_ 3   c  by the first sub-moving portion MVP_ 3   a  may be changed depending on the shape of the adsorption portion ADP connected to the third sub-moving portion MVP_ 3   c.    
     The peeling device PD may further include a first nozzle NZ 1 , a second nozzle NZ 2 , a third nozzle NZ 3 , a rail RL, and a controller CTL. The first, second, and third nozzles NZ 1 , NZ 2 , and NZ 3  will be described later with reference to  FIG. 7B . 
     The rail RL may connect the first moving portion MVP_ 1  and the peeling tank PT. The first moving portion MVP_ 1  may move in the first direction DR 1  or in the direction that is opposite to the first direction DR 1  along the rail RL. 
     The controller CTL may be coupled with the moving portion MVP, and may control a movement of the moving portion MVP that is used to move the adsorption portion ADP. In addition, the controller CTL may control a position of the support portion SPT, the temperature of the first solution SL 1  in the peeling tank PT, and the operation of the first, second, and third nozzles NZ 1 , NZ 2 , and NZ 3 . 
       FIG. 5A  is a view showing a process of adsorbing the second base layer BS 2  onto the adsorption device ADD according to some embodiments of the present disclosure, and  FIG. 5B  is a plan view of the second base layer to show adsorption points AP according to some embodiments of the present disclosure. 
     In  FIGS. 5A to 9 , the same reference numerals denote the same elements in  FIG. 4 , and thus, detailed descriptions of the same elements will be omitted. 
     Referring to  FIG. 5A , the second base layer BS 2  may include an upper surface US, which is adsorbed onto the adsorption portion ADP, and a lower surface DS, which is coupled with the film FL. 
     The second moving portion MVP_ 2  may move in the direction that is opposite to the third direction DR 3  to allow the adsorption pad SP of the adsorption portion ADP to be adsorbed to the second base layer BS 2 . In this case, the second moving portion MVP_ 2  may move the adsorption portion ADP to a first position PS 1 . 
     Referring to  FIG. 5B , the second base layer BS 2  may include a first area AR 1  located at a center portion of the second base layer BS, and a second area AR 2  around the first area AR 1 . When positions at which the adsorption pads SP are absorbed to the second base layer BS 2  are referred to as the adsorption points AP, the adsorption points AP may be located in the second area AR 2 . As an example, the adsorption pads SP may be adsorbed to the second base layer BS 2  at one end among both ends of long sides extending in the first direction DR 1  of the second base layer BS 2 . In addition, the adsorption pads SP may include three adsorption pads. However, the number of the adsorption pads SP should not be particularly limited. 
       FIG. 6  is a view showing a process of peeling the first base layer BS 1  from the film FL according to some embodiments of the present disclosure. 
     As an example, the second moving portion MVP_ 2  may move in the third direction DR 3  to move the adsorption portion ADP to a second position PS 2  from the first position PS 1 . The first and second base layers BS 1  and BS 2  containing a thin film glass substrate may have a specific gravity that is greater than that of the first solution SL 1  containing the water. Accordingly, the second base layer BS 2  adsorbed to the adsorption portion ADP may move in the third direction DR 3  together with the adsorption portion ADP, however, the first base layer BS 1  that is not adsorbed to the adsorption portion ADP may not move on the support stage SPT_ 1 . On the other hand, the film FL may have a specific gravity that is less than that of the first solution SL 1 . Accordingly, when the second base layer BS 2  moves in the third direction DR 3 , the film FL located under the second base layer BS 2  may move in the third direction DR 3 . Consequently, the adsorption portion ADP may move to the second position PS 2  from the first position PS 1  by the second moving portion MVP_ 2 . Thus, the film FL may be peeled off from the first base layer BS 1 , and the second base layer BS 2  may be separated from the first base layer BS 1 . 
     As an example, the support stage SPT_ 1  may move in the direction that is opposite to the third direction DR 3  by the moving stage SPT_ 2  while the adsorption portion ADP moves to the second position PS 2  from the first position PS 1  by the second moving portion MVP_ 2 . In the case where the support stage SPT_ 1  moves in the direction that is opposite to the third direction DR 3 , the first base layer BS 1  located on the support stage SPT_ 1  may move in the direction that is opposite to the third direction DR 3 . Accordingly, a separation distance between the film FL and the first base layer BS 1 , and a separation distance between the second base layer BS 2  and the first base layer BS 1 , may be further obtained. As the separation distance between the first base layer BS 1  and the second base layer BS 2  is further obtained, damage on the second base layer BS 2  caused by the first base layer BS 1  during the process of rotating the second base layer BS 2  in the third direction DR 3  may be reduced or prevented. As an example, the separation distance between the film FL and the first base layer BS 1  separated from the film FL may be tens of centimeters. 
     As an example, the first and second base layers BS 1  and BS 2  may be flexible. Accordingly, a portion of the second base layer BS 2 , which is close to the portion of the second base layer BS 2  adsorbed onto the adsorption portion ADP, may move in the third direction DR 3  together with the adsorption portion ADP, and a portion of the second base layer BS 2 , which is farther away from the portion of the second base layer BS 2  adsorbed onto the adsorption portion ADP, may sag down by gravity. In this case, only a portion of the film FL located at a lower end of the second base layer BS 2 , which is close to the portion adsorbed to the adsorption portion ADP, may be peeled off from the first base layer BS 1 , and the other portion of the film FL located at the lower end of the second base layer BS 2 , which is farther away from the portion adsorbed to the adsorption portion ADP, might not be peeled off from the first base layer BS 1 . 
       FIG. 7A  is a view showing a process of moving the adsorption portion ADP to allow the second base layer BS 2  to be bent toward the third direction according to some embodiments of the present disclosure, and  FIG. 7B  is an enlarged view showing a portion of the peeling device PD corresponding to an area AA′ of  FIG. 7A  to explain the first to third nozzles NZ 1  to NZ 3 . 
     Referring to  FIG. 7A , the first sub-moving portion MVP_ 3   a  may rotate the third sub-moving portion MVP_ 3   c  in a counter-clockwise direction. Because the third sub-moving portion MVP_ 3   c  is connected to the adsorption portion ADP adsorbed to the second base layer BS 2 , the first sub-moving portion MVP_ 3   a  may rotate the third sub-moving portion MVP_ 3   c  and may move the adsorption portion ADP to allow the second base layer BS 2  to be bent. 
     As an example, when the first sub-moving portion MVP_ 3   a  moves the adsorption portion ADP, the first moving portion MVP_ 1  may move in the direction that is opposite to the first direction DR 1 , and the second moving portion MVP_ 2  may move in the third direction DR 3 . However, the movement direction of the first and second moving portions MVP_ 1  and MVP_ 2  and the rotation direction of the first sub-moving portion MVP_ 3   a  may be changed depending on the shape of the peeling device PD. 
     As an example, the third direction DR 3  may be substantially perpendicular to the first direction DR 1 . That is, the first sub-moving portion MVP_ 3   a  may move the adsorption portion ADP such that the second base layer BS 2  is bent to a direction substantially perpendicular to the first direction DR 1 . However, the third direction DR 3  should not be limited to the direction perpendicular to the first direction DR 1 . As an example, the third direction DR 3  may be a direction that forms an angle of about 70° with the first direction DR 1 . 
     The portion of the second base layer BS 2 , which is close to the portion adsorbed to the adsorption pad SP, may be bent to the third direction DR 3  and may be exposed above the water surface of the first solution SL 1  contained in the peeling tank PT. In this case, the film FL located at a lower end of the exposed portion of the second base layer BS 2  may be dragged in the direction that is opposite to the third direction DR 3  by a surface resistance of the first solution. Accordingly, the exposed portion of the second base layer BS 2  may be peeled off from the film FL located at the lower end of the exposed portion. An area of the lower surface DS of the second base layer BS 2  coupled with the film FL, which is peeled off from the film FL, may be defined as a peeling area PR. A portion of the upper surface US of the second base layer BS 2 , which is bent to the third direction DR 3  by the adsorption device ADD, may be defined as a curved area CR. 
     Referring to  FIG. 7B , the first nozzle NZ 1  and the second nozzle NZ 2  may be located above the water surface of the first solution SL 1  contained in the peeling tank PT. When the second base layer BS 2  is bent to the third direction DR 3  by the adsorption device ADD, the first nozzle NZ 1  may be located to face the peeling area PR of the lower surface DS of the second base layer BS 2 . When the second base layer BS 2  is bent to the third direction DR 3  by the adsorption device ADD, the second nozzle NZ 2  may be located to face the curved area CR of the upper surface US of the second base layer BS 2 . 
     In order to peel off the second base layer BS 2  from the film FL, the adsorption part ADP is moved to allow the second base layer BS 2  to be bent toward the third direction DR 3 . At this time, the second solution SL 2  is being sprayed toward the peeling area PR and the film FL through the first nozzle NZ 1 , and thus, the second base layer BS 2  may be easily peeled off from the film FL. A third solution SL 3  may be sprayed to the upper surface US of the second base layer BS 2  via the second nozzle NZ 2 , and thus, foreign substances in the peeling tank PT may be reduced or prevented from remaining in the second base layer BS 2 . As an example, the second and third solutions SL 2  and SL 3  may include the same material as that of the first solution SL 1 . The second and third solutions SL 2  and SL 3  may include water. 
     As an example, the third nozzle NZ 3  may be located on a bottom of the peeling tank PT. The third nozzle NZ 3  may spray a fourth solution SL 4  to the third direction DR 3  to prevent the second base layer BS 2  and the film FL from sinking in the direction that is opposite to the third direction DR 3 . The fourth solution SL 4  may include the same material as that of the first solution SL 1 . 
       FIG. 8  is a view showing a process of taking the second base layer BS 2  out of the peeling tank PT according to some embodiments of the present disclosure. 
     Referring to  FIG. 8 , the second moving portion MVP_ 2  may move in the third direction DR 3  to move the adsorption portion ADP in the third direction DR 3 . Because the second base layer BS 2  is adsorbed to the adsorption portion ADP, the second moving portion MVP_ 2  may move the adsorption portion ADP in the third direction DR 3 , and may take the second base layer BS 2  out of the peeling tank PT. 
     Referring to  FIGS. 7A and 7B  again, the portion of the second base layer BS 2 , which is close to the portion adsorbed to the adsorption pad SP, may be exposed above the surface of the first solution SL 1  contained in the peeling tank PT. Accordingly, when the adsorption portion ADP moves in the third direction DR 3  to take the second base layer BS 2  out of the peeling tank PT, the entire second base layer BS 2  located under the surface of the first solution SL 1  does not move in the third direction DR 3  at once, and the second base layer is moved in the third direction DR 3  gradually starting from the portion of the second base layer BS 2  that is initially exposed above the water surface of the first solution SL 1 . The second base layer BS 2  located under the water surface of the first solution SL 1  may be dragged in the direction that is opposite to the third direction DR 3  by the surface resistance of the first solution SL 1  when moving in the third direction DR 3 . 
     Accordingly, in a case where the second base layer BS 2  is taken out of the peeling tank PT without performing the process of bending the second base layer BS 2  to the third direction DR 3  using the adsorption device ADD (e.g., according to embodiments of the present disclosure), the entire second base layer BS 2  may be dragged by the first solution SL 1  and may be damaged. On the other hand, in the case where the second base layer BS 2  is taken out of the peeling tank PT after bending the second base layer BS 2  to the third direction DR 3  using the adsorption device ADD according to embodiments of the present disclosure, the drag applied to the second base layer BS 2  from the first solution SL 1  may be reduced, and thus, damage to the second base layer BS 2  may be prevented or reduced. 
       FIG. 9  is a view showing a process of removing the film FL out of the peeling tank PT using a grip device GRP according to some embodiments of the present disclosure. 
     Referring to  FIG. 9 , the peeling device PD may further include the grip device GRP that grips the film FL and removes the film FL out of the peeling tank PT. 
     After the second base layer BS 2  (refer to  FIG. 8 ) is peeled off from the film FL and taken out of the peeling tank PT using the adsorption device ADD, the film FL and the first base layer BS 1 , which are separated from each other due to the difference in specific gravity, may remain in the peeling tank PT.  FIGS. 4 to 9  show the stack structure LM including the first and second base layers BS 1  and BS 2  and one film FL located between the first and second base layers BS 1  and BS 2 , however, the stack structure LM may include a plurality of base layers and a plurality of films coupling the base layers to each other. Accordingly, in another example, after the second base layer BS 2  is taken out of the peeling tank PT, an additional process of peeling the first base layer BS 1  from another film, and taking the first base layer BS 1  out of the peeling tank PT may be repeated. In this case, the film FL remaining in the peeling tank PT and located above the first base layer BS 1  is required to be removed to adsorb the adsorption portion ADP onto the first base layer BS 1 . Accordingly, the grip device GRP may grip the remaining film FL and may remove the film FL from the peeling tank PT. However, the shape of the grip device GRP shown in  FIG. 9  is merely an example. The grip device GRP may have a variety of shapes to perform the operation of removing the film FL. 
     When the film FL is removed by the grip device GRP, the adsorption device ADD may allow the first base layer BS 1  to be adsorbed to the adsorption portion ADP. In this case, the support stage SPT_ 1  may move in the third direction DR 3  by the moving stage SPT_ 2 . When the support stage SPT_ 1  moves in the third direction DR 3 , the first base layer BS 1  located on the support stage SPT_ 1  may also move in the third direction DR 3 . Accordingly, the first base layer BS 1  may be easily adsorbed to the adsorption portion ADP. 
     According to the present disclosure, the second base layer BS 2  is peeled off of the film FL using the peeling device PD instead of manually peeling the second base layer BS 2  from the film FL by an operator, and thus, reliability and efficiency of the peeling process of the second base layer BS 2  may be improved. 
       FIG. 10  is a flowchart showing a peeling method of the peeling device according to some embodiments of the present disclosure, and  FIG. 11  is a flowchart showing a process of peeling the base layer from the film, and a process of spraying the second and third solutions through the first and second nozzles, according to some embodiments of the present disclosure. 
     Referring to  FIGS. 4 and 10 , the peeling method using the peeling device PD may include locating the stack structure LM that includes the first and second base layers BS 1  and BS 2  extending in the first direction DR 1 , along with the film FL coupled with the first and second base layers BS 1  and BS 2 , on the support portion SPT that is located in the peeling tank PT containing the first solution SL 1  (S 100 ). In addition, the peeling method using the peeling device PD may include adsorbing the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ), and gripping the film FL using the grip device GRP (refer to  FIG. 9 ) to remove the film FL from the peeling tank (S 300 ). 
     Referring to  FIGS. 5A and 10 , the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ) may include adsorbing the adsorption portion ADP to the second base layer BS 2  (S 201 ). 
     Referring to  FIGS. 6 and 10 , the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ) may include moving the adsorption portion ADP to the second position PS 2  from the first position PS 1  to peel off the first base layer BS 1  from the film FL (S 202 ). 
     Referring to  FIGS. 7A and 10 , the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ) may include moving the adsorption portion ADP to allow the second base layer BS 2  to be bent to a third direction DR 3  crossing the first direction DR 1  and to be peeled off from the film FL (S 203 ). 
     Referring to  FIGS. 8 and 10 , the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ) may further include moving the adsorption portion ADP in the third direction DR 3  to take the second base layer BS 2  out of the peeling tank PT. 
     Referring to  FIGS. 9 and 10 , after the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ), gripping the film FL using the grip device GRP to remove the film FL from the peeling tank (S 300 ) may be performed. 
     Referring to  FIGS. 7B and 11 , the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ) may further include spraying the second solution SL 2  to the peeling area PR of the lower surface DS of the second base layer BS 2  and the film FL via the first nozzle NZ 1  (S 204 ). In addition, the adsorbing of the second base layer BS 2  to peel off the second base layer BS 2  from the film FL (S 200 ) may further include spraying the third solution SL 3  to the upper surface US of the second base layer BS 2  via the second nozzle NZ 2  (S 205 ). 
     As an example, the spraying of the second solution SL 2  via the first nozzle NZ 1  (S 204 ) and the spraying of the third solution SL 3  via the second nozzle NZ 2  (S 205 ) may be substantially simultaneously performed with the peeling off of the second base layer BS 2  from the film FL (S 203 ). 
     Although embodiments of the present disclosure have been described, it is understood that the present disclosure should not be limited to these embodiments but various changes and modifications can be made by one ordinary skilled in the art within the spirit and scope of the present disclosure as hereinafter claimed. 
     Therefore, the disclosed subject matter should not be limited to any of the embodiments described herein, and the scope of the present disclosure shall be determined according to the attached claims, with the functional equivalents thereof to be included therein.