Patent Publication Number: US-2021176879-A1

Title: Display module and method of fabricating the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from and the benefit of Korean Patent Application No. 10-2019-0159945, filed on Dec. 4, 2019, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
     BACKGROUND OF THE INVENTION 
     Field 
     Embodiments/implementations of the invention relate generally to a display module with improved reliability and a method of fabricating the same. 
     Discussion of the Background 
     Various display devices are being developed for use in multimedia devices such as televisions, mobile phones, navigation systems, computer monitors, gaming machines, and the like. The display device includes a display panel providing image information to a user and a window protecting the display panel. The window may be combined to the display panel. To combine the window to the display panel, it is necessary to align the window to the display panel. 
     The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art. 
     SUMMARY 
     Devices constructed according to embodiments of the invention are capable of providing a display module with improved reliability and methods according to exemplary implementations are capable of fabricating the same. 
     Additional features of the inventive concepts will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts 
     According to an embodiment of the inventive concepts, a method of fabricating a display device may include preparing a display panel, attaching a film portion to the display panel, forming an alignment key on or in the film portion, recognizing the alignment key using an alignment module with a camera, aligning a window to the film portion using the alignment module, removing at least a portion of the film portion, and combining the display panel with the window. 
     In an embodiment, the film portion may include an optical film and a protection film disposed on the optical film, and the forming of the alignment key on or in the film portion is may include forming the alignment key on or in a top surface of the protection film. 
     In an embodiment, the removing of at least the portion of the film portion may include removing the protection film. 
     In an embodiment, the forming of the alignment key may include patterning a top surface of the film portion using a laser beam. 
     In an embodiment, the forming of the alignment key may include printing an ink on a top surface of the film portion. 
     In an embodiment, the forming of the alignment key may be performed before the attaching of the film portion to the display panel. 
     In an embodiment, the forming of the alignment key may be performed after the attaching of the film portion to the display panel. 
     In an embodiment, the display panel may include a first region, which includes a first edge, a second edge extending in a direction crossing the first edge, a third edge parallel to the first edge, and a fourth edge parallel to the second edge, a second region extended from the first edge, a third region extended from the second edge, a fourth region extended from the third edge, and a fifth region extended from the fourth edge. At least a portion of each of the second to fifth regions may be bent. 
     In an embodiment, the alignment key may be formed on at least one of the second to fifth regions. 
     In an embodiment, the alignment key may be formed on the first region. 
     In an embodiment, the forming of the alignment key may include forming a plurality of alignment keys in at least two different shapes. 
     In an embodiment, the display panel may include a display region and a is non-display region adjacent to the display region. The alignment key may be formed at a position overlapped with the display region. 
     In an embodiment, the alignment module may further include a control unit. The method may further include storing position information on an aligned position of the window, in the control unit. 
     In an embodiment, the method may further include aligning the window, using the position information stored in the control unit, after the removing of at least the portion of the film portion. 
     In an embodiment, the recognizing of the alignment key and the aligning of the window may be performed simultaneously. 
     In an embodiment, the alignment key may provide in plural. The film portion may include a first alignment region, a second alignment region adjacent to the first alignment region, a third alignment region adjacent to the first alignment region and spaced apart from the second alignment region, and a fourth alignment region adjacent to the second and third alignment regions. The forming of the alignment key may include forming the plurality of alignment keys on or in at least two regions of the first to fourth alignment regions. 
     According to an embodiment of the inventive concepts, a display module may include a display panel including a display region and a non-display region adjacent to the display region, an optical film disposed on the display panel, and a protection film disposed on the optical film. At least one alignment key may be provided on or in a top surface of the protection film. 
     In an embodiment, the alignment key may be overlapped with the display region, when viewed in a plan view. 
     In an embodiment, the alignment key may be defined by a hollow region, which is recessed downward from the top surface of the protection film, and a depth of the hollow region may be smaller than a thickness of the protection film. 
     In an embodiment, the alignment key may include an ink pattern provided on the top surface of the protection film. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the inventive concepts. 
         FIG. 1  is a perspective view illustrating a display device according to an embodiment of the inventive concepts. 
         FIG. 2  is a perspective view illustrating an exploded structure of a display device according to an embodiment of the inventive concepts. 
         FIG. 3  is a flow chart illustrating a method of fabricating a display device according to an embodiment of the inventive concepts. 
         FIG. 4  is a sectional view illustrating a step of forming an alignment key, according to an embodiment of the inventive concepts. 
         FIG. 5  is a plan view illustrating a film portion according to an embodiment of the is inventive concepts. 
         FIGS. 6A and 6B  are perspective views illustrating a step of attaching a film portion on a display panel, according to an embodiment of the inventive concepts. 
         FIG. 7  is a perspective view illustrating a part of a method of fabricating a display device, according to an embodiment of the inventive concepts. 
         FIG. 8  is a perspective view illustrating a step of removing a portion of a film portion, according to an embodiment of the inventive concepts. 
         FIGS. 9 and 10  are sectional views illustrating a step of combining a window with a display panel, according to an embodiment of the inventive concepts. 
         FIG. 11  is a sectional view illustrating a step of forming an alignment key on a film portion, according to an embodiment of the inventive concepts. 
         FIG. 12  is a flow chart illustrating a method of fabricating a display device, according to an embodiment of the inventive concepts. 
         FIG. 13  is a sectional view illustrating a step of forming an alignment key, according to an embodiment of the inventive concepts. 
         FIG. 14  is a sectional view illustrating a step of forming an alignment key, according to an embodiment of the inventive concepts. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various embodiments or implementations of the invention. As used herein “embodiments” and “implementations” are interchangeable words that are non-limiting examples of devices or methods employing one or is more of the inventive concepts disclosed herein. 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. Further, various embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an embodiment may be used or implemented in another embodiment without departing from the inventive concepts. 
     Unless otherwise specified, the illustrated embodiments are to be understood as providing exemplary features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts. 
     The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an embodiment 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 is substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements. 
     When an element, such as a layer, is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without intervening elements. Further, the DR 1 -axis, the DR 2 -axis, and the DR 3 -axis are not limited to three axes of a rectangular coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the DR 1 -axis, the DR 2 -axis, and the DR 3 -axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure. 
     Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for is descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art. 
     Various embodiments are described herein with reference to sectional and/or exploded illustrations that are schematic illustrations of idealized embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for is example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. In this manner, regions illustrated in the drawings may be schematic in nature and the shapes of these regions may not reflect actual shapes of regions of a device and, as such, are not necessarily intended to be limiting. 
     As is customary in the field, some embodiments are described and illustrated in the accompanying drawings in terms of functional blocks, units, and/or modules. Those skilled in the art will appreciate that these blocks, units, and/or modules are physically implemented by electronic (or optical) circuits, such as logic circuits, discrete components, microprocessors, hard-wired circuits, memory elements, wiring connections, and the like, which may be formed using semiconductor-based fabrication techniques or other manufacturing technologies. In the case of the blocks, units, and/or modules being implemented by microprocessors or other similar hardware, they may be programmed and controlled using software (e.g., microcode) to perform various functions discussed herein and may optionally be driven by firmware and/or software. It is also contemplated that each block, unit, and/or module may be implemented by dedicated hardware, or as a combination of dedicated hardware to perform some functions and a processor (e.g., one or more programmed microprocessors and associated circuitry) to perform other functions. Also, each block, unit, and/or module of some embodiments may be physically separated into two or more interacting and discrete blocks, units, and/or modules without departing from the scope of the inventive concepts. Further, the blocks, units, and/or modules of some embodiments may be physically combined into more complex blocks, units, and/or modules without departing from the scope of the inventive concepts. 
     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 this disclosure is a part. 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 should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein. 
       FIG. 1  is a perspective view illustrating a display device according to an embodiment of the inventive concepts. 
     Referring to  FIG. 1 , a display device DD may be activated by an electrical signal applied thereto. The display device DD may be realized in various forms. For example, the display device DD may be used for large-sized electronic devices (e.g., television sets and monitors) or small- or medium-sized electronic devices (e.g., mobile phones, tablets, car navigation systems, game machines, and smart watches). In the present embodiment, the display device DD may be a smart phone, as illustrated in  FIG. 1 . 
     A display region DA may be defined in the display device DD. The display region DA may include a first display region DA 1 , a second display region DA 2 , a third display region DA 3 , a fourth display region DA 4 , and a fifth display region DA 5 . 
     The first display region DA 1  may be parallel to a plane defined by a first direction DR 1  and a second direction DR 2 . A normal direction of the first display region DA 1  may correspond to a thickness direction DR 3  (hereinafter, a third direction) of the display device DD. In the present specification, the third direction DR 3  will be used to differentiate a front or top surface and a rear or bottom surface of each element or member. The front and rear surfaces may be two surfaces that are opposite to each other in the third direction DR 3 . The third is direction DR 3  may not be parallel to the first and second directions DR 1  and DR 2 . In an embodiment, the first, second, and third directions DR 1 , DR 2 , and DR 3  may be orthogonal to each other. 
     In the present specification, directions indicated by the first to third directions DR 1 , DR 2 , and DR 3  may be relative concept, and in an embodiment, they may be used to indicate other directions. Furthermore, a surface defined by the first and second directions DR 1  and DR 2  may be defined as “a plane”, and an expression “when viewed in a plan view” may be used to mean that an object is seen in the third direction DR 3 . 
     The second display region DA 2  may be a region that is extended from a first edge of the first display region DA 1 . The third display region DA 3  may be a region that is extended from a second edge of the first display region DA 1 . The fourth display region DA 4  may be a region that is extended from a third edge of the first display region DA 1 . The fifth display region DA 5  may be a region that is extended from a fourth edge of the first display region DA 1 . 
     Each of the second, third, fourth, and fifth display regions DA 2 , DA 3 , DA 4 , and DA 5  may be curved with a specific curvature. 
     Due to the curved shapes of the second, third, fourth, and fifth display regions DA 2 , DA 3 , DA 4 , and DA 5  of the display device DD, an area of the display region DA to be seen by a user may be increased. 
     The display region DA may be used to display an image IM.  FIG. 1  illustrates an example, in which a clock window and some icons are provided as a part of the image IM. In an embodiment, the clock window may be displayed on the first display region DA 1 , and the icons may be displayed on at least one of the second to fifth display regions D 2 , D 3 , D 4 , and D 5 . 
       FIG. 2  is a perspective view illustrating an exploded structure of a display device is according to an embodiment of the inventive concepts. 
     Referring to  FIG. 2 , the display device DD may include a window WM, an optical film POL, a display panel DP, a printed circuit board PCB-M, a supporting member SPT, and a frame FRM. 
     The window WM may be disposed on the display panel DP. The window WM may protect the display panel DP from an external impact or the like. The window WM may be formed of or include a transparent material. For example, the window WM may be formed of or include at least one of glass or transparent synthetic resins. 
     The window WM may include transmission regions TA 1 , TA 2 , TA 3 , TA 4 , and TA 5 . The transmission regions TA 1 , TA 2 , TA 3 , TA 4 , and TA 5  may include a first transmission region TA 1 , a second transmission region TA 2 , a third transmission region TA 3 , a fourth transmission region TA 4 , and a fifth transmission region TA 5 . 
     The first transmission region TA 1  may be parallel to the first and second directions DR 1  and DR 2 . The first transmission region TA 1  may include a first edge ED 1  extended in a direction parallel to the first direction DR 1 , a second edge ED 2  extended from the first edge ED 1  in a direction parallel to the second direction DR 2 , a third edge ED 3  extended from the second edge ED 2  in a direction parallel to the first direction DR 1 , and a fourth edge ED 4  extended from the third edge ED 3  in a direction parallel to the second direction DR 2 . The first edge ED 1  and the third edge ED 3  may be parallel to each other, and the second edge ED 2  and the fourth edge ED 4  may be parallel to each other. 
     The second transmission region TA 2  may be extended from the first edge ED 1  of the first transmission region TA 1 . The third transmission region TA 3  may be extended from the second edge ED 2  of the first transmission region TA 1 . The fourth transmission region TA 4  is may be extended from the third edge ED 3  of the first transmission region TA 1 . The fifth transmission region TA 5  may be extended from the fourth edge ED 4  of the first transmission region TA 1 . 
     At least a portion of each of the second, third, fourth, and fifth transmission regions TA 2 , TA 3 , TA 4 , and TA 5  may be bent with a specific curvature. 
     The optical film POL may be disposed between the window WM and the display panel DP. The optical film POL may include, for example, a polarization film. The polarization film may reduce reflectance of an external light incident through the window WM. 
     The display panel DP may be an element producing the image IM (e.g., see FIG.  1 ). According to an embodiment of the inventive concepts, the display panel DP may be a light-emitting type display panel, but the inventive concepts are not limited to a specific type of the display panel DP. For example, the display panel DP may be an organic light emitting display panel or a quantum dot light emitting display panel. A light emitting layer of the organic light emitting display panel may be formed of or include an organic luminescent material. A light emitting layer of the quantum dot light emitting display panel may include quantum dots and/or quantum rods. 
     The display panel DP may include a first region AR 1 , a second region AR 2 , a third region AR 3 , a fourth region AR 4 , a fifth region AR 5 , and a sixth region AR 6 . 
     The first region AR 1  may be parallel to the first and second directions DR 1  and DR 2 . The first region AR 1  may include a first edge ED 11  extending in a direction parallel to the first direction DR 1 , a second edge ED 12  extending in a direction parallel to the second direction DR 2 , a third edge ED 13  extending in a direction parallel to the first direction DR 1 , and a fourth edge ED 14  extending in a direction parallel to the second direction DR 2 . The first is edge ED 11  and the third edge ED 13  may be parallel to each other, and the second edge ED 12  and the fourth edge ED 14  may be parallel to each other. 
     The second region AR 2  may be extended from the first edge ED 11  of the first region AR 1 . The third region AR 3  may be extended from the second edge ED 12  of the first region AR 1 . The fourth region AR 4  may be extended from the third edge ED 13  of the first region AR 1 . The fifth region AR 5  may be extended from the fourth edge ED 14  of the first region AR 1 . 
     When viewed in a plan view, the first region AR 1  may be overlapped with the first transmission region TA 1 . The second region AR 2  may be overlapped with the second transmission region TA 2 . The third region AR 3  may be overlapped with the third transmission region TA 3 . The fourth region AR 4  may be overlapped with the fourth transmission region TA 4 . The fifth region AR 5  may be overlapped with the fifth transmission region TA 5 . 
     The first region AR 1  may display the image IM (e.g., see  FIG. 1 ) through the first transmission region TA 1 . The second region AR 2  may display the image IM (e.g., see  FIG. 1 ) through the second transmission region TA 2 . The third region AR 3  may display the image IM (e.g., see  FIG. 1 ) through the third transmission region TA 3 . The fourth region AR 4  may display the image IM (e.g., see  FIG. 1 ) through the fourth transmission region TA 4 . The fifth region AR 5  may display the image IM (e.g., see  FIG. 1 ) through the fifth transmission region TA 5 . 
     The second, third, fourth, and fifth regions AR 2 , AR 3 , AR 4 , and AR 5  may be bent with specific curvatures, such that they have shapes corresponding to the second, third, fourth, and fifth transmission regions TA 2 , TA 3 , TA 4 , and TA 5 . 
     In the present specification, the first region AR 1  may be referred to as the first is display region DA 1  (e.g., see  FIG. 1 ). The second region AR 2  may be referred to as the second display region DA 2  (e.g., see  FIG. 1 ). The third region AR 3  may be referred to as the third display region DA 3  (e.g., see  FIG. 1 ). The fourth region AR 4  may be referred to as the fourth display region DA 4  (e.g., see  FIG. 1 ). The fifth region AR 5  may be referred to as the fifth display region DA 5  (e.g., see  FIG. 1 ). 
     A first corner region EG 1  may be a surface adjacent to the second region AR 2  and the fifth region AR 5 . The first corner region EG 1  may be disposed between the second region AR 2  and the fifth region AR 5 . The first corner region EG 1  may have an edge of a convex shape, when viewed in a plan view. A second corner region EG 2  may be a surface adjacent to the second region AR 2  and the third region AR 3 . The second corner region EG 2  may be disposed between the second region AR 2  and the third region AR 3 . The second corner region EG 2  may have an edge of a convex shape, when viewed in a plan view. A third corner region EG 3  may be a surface adjacent to the third region AR 3  and the fourth region AR 4 . The third corner region EG 3  may be disposed between the third region AR 3  and the fourth region AR 4 . The third corner region EG 3  may have an edge of a convex shape, when viewed in a plan view. A fourth corner region EG 4  may be a surface adjacent to the fourth region AR 4  and the fifth region AR 5 . The fourth corner region EG 4  may be disposed between the fourth region AR 4  and the fifth region AR 5 . The fourth corner region EG 4  may have an edge of a convex shape, when viewed in a plan view. 
     The sixth region AR 6  may be extended from the fourth region AR 4  and in the second direction DR 2 . The sixth region AR 6  may include an upper region AR-H, a bending region BA, and a lower region AR-L. 
     The upper region AR-H may be extended from the fourth region AR 4 , the is bending region BA may be extended from the upper region AR-H, and the lower region AR-L may be extended from the bending region BA. 
     Pads PD may be disposed on the lower region AR-L, and a data driving circuit DIC may be mounted on the lower region AR-L. The pads PD may be electrically connected to the light emitting layer of the display panel DP. The data driving circuit DIC may provide data signals to the display region DA (e.g., see  FIG. 1 ). The display panel DP may be electrically connected to the printed circuit board PCB-M via the pads PD. A control circuit CIC may be mounted on the printed circuit board PCB-M. The control circuit CIC may control the data driving circuit DIC. 
     The supporting member SPT may be disposed below the display panel DP. The supporting member SPT may support at least one of elements constituting the display panel DP. 
     The frame FRM may be disposed below the supporting member SPT. The frame FRM may be configured to contain at least a portion of the supporting member SPT, the display panel DP, and the window WM. In an embodiment, the frame FRM may be combined with the window WM. 
       FIG. 3  is a flow chart illustrating a method of fabricating a display device according to an embodiment of the inventive concepts, and  FIG. 4  is a sectional view illustrating a step of forming an alignment key, according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3 and 4 , a film portion FP may include the optical film POL and a protection film PF. The protection film PF may be disposed on the optical film POL. The protection film PF may protect the optical film POL. 
     An alignment key AK may be formed in the film portion FP (in S 100 ). The alignment key AK may be formed in advance before attaching the film portion FP to the display is panel DP. 
     A laser irradiation unit LM may be placed over the protection film PF. The laser irradiation unit LM may be configured to irradiate a laser beam LZ. The laser beam LZ may include an excimer laser, an yttrium aluminum garnet (YAG) laser, a glass laser, an yttrium orthovanadate (YVO4) laser, or an Argon (Ar) laser. 
     The laser beam LZ may be used to perform a patterning process on a top surface PF-U of the protection film PF. For example, the laser beam LZ may be used to etch the top surface PF-U of the protection film PF in the third direction DR 3  and thereby to form a hollow region. A thickness TK-PF of the protection film PF may be larger than or equal to a depth TK-AK of the hollow region of the alignment key AK. The hollow region may constitute the alignment key AK. 
       FIG. 5  is a plan view illustrating a film portion according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3 and 5 , the film portion FP may include a first alignment region AA 1 , a second alignment region AA 2 , a third alignment region AA 3 , and a fourth alignment region AA 4 . 
     The second alignment region AA 2  may be adjacent to the first alignment region AA 1  in the first direction DR 1 . The third alignment region AA 3  may be adjacent to the first alignment region AA 1  in the second direction DR 2  and may be spaced apart from the second alignment region AA 2 . The fourth alignment region AA 4  may be adjacent to the second alignment region AA 2  in the second direction DR 2  and may be adjacent to the third alignment region AA 3  in the first direction DR 1 . 
     In an embodiment, a plurality of the alignment keys AK may be provided. The is alignment keys AK may include a first alignment key AK 1  and a second alignment key AK 2 .  FIG. 5  illustrates an example, in which two alignment keys AK are provided, but the number of the alignment keys is not limited thereto. For example, four alignment keys may be disposed in the first, second, third, and fourth alignment regions AA 1 , AA 2 , AA 3 , and AA 4 , respectively. 
     In an embodiment, the alignment keys AK may be formed in at least two regions of the first, second, third, and fourth alignment regions AA 1 , AA 2 , AA 3 , and AA 4 . For example, the first alignment key AK 1  may be disposed in the first alignment region AA 1 , and the second alignment key AK 2  may be disposed in the fourth alignment region AA 4 . However, the inventive concepts are not limited to this example, and the positions of the first and second alignment keys AK 1  and AK 2  may be changed. 
     In an embodiment, all or some of the alignment keys AK may be disposed in one of the first, second, third, and fourth alignment regions AA 1 , AA 2 , AA 3 , and AA 4  of the protection film PF. 
     An example, in which one first alignment key AK 1  is disposed in the first alignment region AA 1 , is illustrated, but the inventive concepts are not limited to this example. For example, two or more alignment keys may be disposed in the first alignment region AA 1 . 
     In an embodiment, the alignment keys AK may be formed to have at least two different shapes. For example, the first alignment key AK 1  may be formed to have a rectangular shape, whereas the second alignment key AK 2  may be formed to have a diamond shape. However, the inventive concepts are not limited to the shape of the alignment keys. For example, each of the alignment keys may be formed to have a polygonal, cross, elliptical, or circular shape. In an embodiment, all of the alignment keys AK may be formed to have the same shape. 
       FIG. 6A  is a perspective view illustrating a step of attaching a film portion on a display panel, according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3 and 6A , a display module DM may be prepared. The display module DM may include the display panel DP and the film portion FP. The display panel DP may be disposed on a stage ST. The film portion FP with the alignment keys AK may be attached to the display panel DP (in S 200 ). 
     A first adhesive layer (not shown) may be disposed between the display panel DP and the film portion FP. The first adhesive layer may be an optically clear adhesive (OCA) film, an optically clear resin (OCR) film, or a pressure sensitive adhesive (PSA) film. 
     In an embodiment, the film portion FP may be attached to the display panel DP such that the alignment keys AK 1  and AK 2  are disposed on the display region DA (e.g., see  FIG. 1 ). 
     When viewed in a plan view, the alignment keys AK 1  and AK 2  may be disposed or formed at positions that are overlapped with the display region DA (e.g., see  FIG. 1 ). The alignment keys AK 1  and AK 2  may be disposed or formed on the first region AR 1 . When viewed in a plan view, the alignment keys AK 1  and AK 2  may not be overlapped with the non-display region NDA (e.g., see  FIG. 1 ). 
     In an embodiment, the alignment keys AK 1  and AK 2  may be disposed on the display region DA (e.g., see  FIG. 1 ). In this case, the alignment keys AK 1  and AK 2  may be seen in front of the display panel DP, even when at least a portion of the display panel DP is bent. Accordingly, it may be possible to combine the window WM (e.g., see  FIG. 2 ) to the display panel DP with improved accuracy. This may make it possible to realize a highly-reliable display device (e.g., DD in  FIG. 1 ) and a method of fabricating the same. 
       FIG. 6B  is a perspective view illustrating a step of attaching a film portion on a display panel, according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3 and 6B , a display module DMa may include the display panel DP and a film portion FPa. The film portion FPa may be attached on the display panel DP (in S 200 ). Alignment keys AK 1   a  and AK 2   a  may be formed at positions that are overlapped with the display region DA (e.g., see  FIG. 1 ). 
     The alignment keys AK 1   a  and AK 2   a  may be formed or disposed on at least one of the second, third, fourth, and fifth regions AR 2 , AR 3 , AR 4 , and AR 5 . For example, the first alignment key AK 1   a  may be formed or disposed on the second region AR 2 , and the second alignment key AK 2   a  may be formed or disposed on the fourth region AR 4 . However, the inventive concepts are not limited to this example, and the positions of the first and second alignment keys AK 1   a  and AK 2   a  may be changed. When viewed in a plan view, the alignment keys AK 1   a  and AK 2   a  may not be overlapped with the non-display region NDA (e.g., see  FIG. 2 ). 
     In certain embodiments, the alignment keys may be formed on not only the first region AR 1  but also at least one of the second, third, fourth, and fifth regions AR 2 , AR 3 , AR 4 , and AR 5 . 
       FIG. 7  is a perspective view illustrating a part of a method of fabricating a display device, according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3 and 7 , an alignment module AM may include a transfer module MO, cameras CM 1  and CM 2 , and a control unit CU. 
     The transfer module MO may be configured to grip the window WM. For example, the transfer module MO may grip the window WM in a suction manner. 
     The cameras CM 1  and CM 2  may be used to recognize the alignment keys AK 1  and AK 2 , respectively (in S 300 ). The cameras CM 1  and CM 2  may be disposed to correspond to the alignment keys AK 1  and AK 2  in a one-to-one manner. The cameras CM 1  and CM 2  may include a first camera CM 1  and a second camera CM 2 . When viewed in a plan view, the first camera CM 1  may be overlapped with the first alignment key AK 1 . The second camera CM 2  may be overlapped with the second alignment key AK 2 .  FIG. 7  illustrates an example, in which two the cameras CM 1  and CM 2  are provided, but the inventive concepts are not limited to this example. In an embodiment, the number of the cameras may be equal to the number of the alignment keys. In certain embodiments, the number of the cameras may be larger or smaller than the number of the alignment keys. 
     In an embodiment, the alignment keys AK 1  and AK 2  may be disposed on the display region DA (e.g., see  FIG. 1 ). A portion of the film portion FP with the alignment keys AK 1  and AK 2  may be removed, before the film portion FP is combined with the window WM. Thus, there may be no restriction on the sizes of the alignment keys AK 1  and AK 2 . This may make it possible to increase the sizes of the alignment keys AK 1  and AK 2 , and in this case, the alignment keys AK 1  and AK 2  may be more accurately recognized by the cameras CM 1  and CM 2 . That is, the combining accuracy between the window WM and the display panel DP may be improved. This may make it possible to realize a highly-reliable display device (e.g., DD in  FIG. 1 ) and a method of fabricating the same. 
     The window WM may be aligned to a desired position on the film portion FP by the alignment module AM (in S 400 ). For example, the alignment position of the window WM may be adjusted by the transfer module MO. The recognizing of the alignment keys AK 1  and AK 2  (in S 300 ) and the aligning of the window WM (in S 400 ) may be simultaneously performed. 
     The control unit CU may store information on the position of the window WM aligned by the transfer module MO as position information. The position information may be obtained from the alignment keys AK 1  and AK 2  recognized by the cameras CM 1  and CM 2 . 
       FIG. 8  is a perspective view illustrating a step of removing a portion of a film portion, according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3 and 8 , at least a portion of the film portion FP may be removed (in S 500 ). For example, the protection film PF of the film portion FP may be removed from the display panel DP and the optical film POL. 
     Although the alignment keys AK 1  and AK 2  are formed or disposed to be overlapped with the display region DA (e.g., see  FIG. 1 ), the presence of the alignment keys AK 1  and AK 2  may not affect the display region DA (e.g., see  FIG. 1 ), because the protection film PF is removed. 
     In an embodiment, the film portion FP may include only the protection film PF, and in this case, the entirety of the film portion FP may be removed from the display panel DP. 
     In an embodiment, the protection film PF with the alignment keys AK 1  and AK 2  may be removed, before the combining of the window WM and the display panel DP. In this case, the alignment keys AK 1  and AK 2  may be formed at positions, which can be easily recognized by the alignment module AM (e.g., see  FIG. 7 ), without any restriction on their positions. Accordingly, it may be possible to easily align the window WM and to improve accuracy in the alignment of the window WM. Furthermore, this may make it possible to improve the combining accuracy between the window WM and the display panel DP. Accordingly, it may be possible to realize a highly-reliable display device (e.g., DD in  FIG. 1 ) and a method of fabricating the same. 
       FIGS. 9 and 10  are sectional views illustrating a step of combining a window with a display panel, according to an embodiment of the inventive concepts. 
     Referring to  FIGS. 3, 9, and 10 , the display panel DP may be combined with the window WM (in S 600 ). The transfer module MO may place the window WM on the display panel DP. The alignment module AM may align the window WM to a position on the display panel DP, using the position information on the aligned position of the window WM, stored in the control unit CU. 
     The display panel DP may be bent. The second region AR 2  (e.g., see  FIG. 2 ) may be bent to have a shape corresponding to that of the second transmission region TA 2  (e.g., see  FIG. 2 ). The third region AR 3  (e.g., see  FIG. 2 ) may be bent to have a shape corresponding to that of the third transmission region TA 3  (e.g., see  FIG. 2 ). The fourth region AR 4  (e.g., see  FIG. 2 ) may be bent to have a shape corresponding to that of the fourth transmission region TA 4  (e.g., see  FIG. 2 ). The fifth region AR 5  (e.g., see  FIG. 2 ) may be bent to have a shape corresponding to that of the fifth transmission region TA 5  (e.g., see  FIG. 2 ). 
     The window WM may be attached to the display panel DP. A second adhesive layer (not shown) may be disposed between the window WM and the optical film POL. The second adhesive layer may be an optically clear adhesive (OCA) film, an optically clear resin (OCR) film, or a pressure sensitive adhesive (PSA) film. 
     In an embodiment, the position information on the position of the window WM, which was determined in the step S 300  of recognizing the alignment keys AK 1  and AK 2  (e.g., see  FIG. 7 ) using the alignment module AM, may be stored in the control unit CU. The positions of the window WM and the transfer module AM may be changed, during the removing of the protection film PF (in S 500 ). Here, a space to remove the protection film PF may be is provided. After the removing of the protection film PF, the display panel DP and the window WM may be re-aligned to each other using the stored position information. The combining of the display panel DP and the window WM (in S 600 ) may be performed when they are aligned to each other. Accordingly, it may be possible to improve accuracy in the combining of the display panel DP and the window WM. This may make it possible to realize a highly-reliable display device (e.g., DD in  FIG. 1 ) and a method of fabricating the same. 
       FIG. 11  is a sectional view illustrating a step of forming an alignment key on a film portion, according to an embodiment of the inventive concepts. In the following description of  FIG. 11 , an element previously described with reference to  FIG. 4  may be identified by the same reference number without repeating an overlapping description thereof. 
     Referring to  FIGS. 3, 4, and 11 , an alignment key AK- 1  may be formed on a film portion FP- 1  (in S 100 ). The forming of the alignment key AK- 1  (in S 100 ) may be performed before the step S 200  of attaching the film portion FP- 1  to the display panel DP. 
     The film portion FP- 1  may include the optical film POL and a protection film PF- 1 . An ink ejection unit IN may be placed over the protection film PF- 1 . The ink ejection unit IN may eject an ink INK. The ink INK may be printed on a top surface PF- 1 U of the protection film PF- 1 . The alignment key AK- 1  may be formed on the top surface PF- 1 U of the protection film PF- 1 . 
     In the case where the printing method using the ink ejection unit IN is used, it may be unnecessary to consider a thickness TK-PF 1  of the protection film PF- 1  in the forming of the alignment key AK- 1 , unlike the case of forming the alignment key AK with the laser irradiation unit LM. Thus, the process of forming the alignment key AK- 1  on the film portion FP may be more easily performed. 
       FIG. 12  is a flow chart illustrating a method of fabricating a display device, according to an embodiment of the inventive concepts, and  FIG. 13  is a sectional view illustrating a step of forming an alignment key, according to an embodiment of the inventive concepts. In the following description of  FIGS. 12 and 13 , an element previously described with reference to  FIGS. 3 and 4  may be identified by the same reference number without repeating an overlapping description thereof. 
     Referring to  FIGS. 12 and 13 , a film portion FP- 2  may be attached to the display panel DP (in S 100 - 1 ). Next, an alignment key AK- 2  may be formed in the film portion FP- 2  (S 200 - 1 ). In other words, the step of forming the alignment key AK- 2  may be performed on the film portion FP- 2  attached to the display panel DP. 
     In an embodiment, the step of forming the alignment key AK- 2  (in S 200 - 1 ) may be performed concurrently with a step of a display device fabrication process, in which the laser beam LZ is used. For example, the step of forming the alignment key AK- 2  in the film portion FP- 2  using the laser beam LZ and a step of cutting the display panel DP using the laser beam LZ may be performed in the same process. In this case, it may be possible to reduce a total process time taken to fabricate a display device. 
     In an embodiment, the alignment key AK- 2  may be disposed to be overlapped with the display region DA (e.g., see  FIG. 1 ). A protection film PF- 2 , in which the alignment key AK- 2  is formed, may be removed before the window WM and the display panel DP are combined with each other, and in this case, the alignment key AK- 2  may be formed at a position, which can be easily recognized by the alignment module AM, without any restriction on its position. That is, the combining accuracy between the window WM and the display panel DP may be improved. This may make it possible to realize a highly-reliable display device (e.g., is DD in  FIG. 1 ) and a method of fabricating the same. 
       FIG. 14  is a sectional view illustrating a step of forming an alignment key, according to an embodiment of the inventive concepts. In the following description of  FIG. 14 , an element previously described with reference to  FIG. 11  may be identified by the same reference number without repeating an overlapping description thereof. 
     Referring to  FIGS. 12 and 14 , a film portion FP- 3  may be attached to the display panel DP. Next, an alignment key AK- 3  may be formed on the film portion FP- 3 . In other words, the step of forming the alignment key AK- 3  may be performed on the film portion FP- 3  attached to the display panel DP. 
     The ink ejection unit IN may be placed over a protection film PF- 3 . The alignment key AK- 3  may be formed by using the ink INK ejected from the ink ejection unit IN. 
     According to an embodiment of the inventive concepts, an alignment key, which is used to align a window to a display panel, may be formed on a film portion to be removed. This may make it possible to dispose the alignment key at a position overlapped with a display region of the display panel. Furthermore, the alignment key may be placed in front of the display panel, even when at least a portion of the display panel is bent. Accordingly, the window may be aligned to the display panel with high alignment accuracy, and thus, the process of combining the window with the display panel may be performed with improved accuracy. 
     Although certain embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art.