PATENT ABSTRACT
Simple and high-precision processing, and narrowing of the frame are to be facilitated at the time of preparing display panels by multiple formation. After bonding a first substrate layer in which a plurality of element substrates is formed on a support plate and a second substrate layer in which a plurality of counter substrates is formed on a support plate, these substrate layers are divided into a plurality of display panels. Ridge-like ribs of a covalently or ionically bonding inorganic material are formed along edges of the element substrate and the counter substrate. The dividing includes scribing the support plates along the ribs, and flexing and breaking the support plates.

PATENT DESCRIPTION
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims priority from Japanese application JP2016-023783 filed on Feb. 10, 2016, the content of which is hereby incorporated by reference into this application. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a display device and a manufacturing method thereof, and particularly to a flexible display. 
         [0004]    2. Description of the Related Art 
         [0005]    A flat panel display such as an organic electroluminescence (EL) display device has a display panel in which a thin film transistor (TFT), an organic light-emitting diode (OLED) and the like are formed on a substrate. Conventionally, a glass substrate is used for the base member of the display panel. However, recently, the development of a flexible display using a resin film or the like as the base member to enable the flexure of the display panel is under way. 
         [0006]    As a structure of the organic EL display device, an element substrate having a display area where an OLED as a display element is formed, and a counter substrate on which a color filter or the like is formed and which is arranged opposite the display area of the element substrate, are bonded together. To secure reliability, the element substrate and the counter substrate are bonded together with a filler held between these substrates. In this case, a method may be used in which a dam having a convex structure is formed at an outer peripheral part of the counter substrate, then the filler is dripped into the dam, and the element substrate and counter substrate are thus bonded together. This dam plays the role of preventing the filler from protruding to the outside. The dam is formed by applying a fluid material onto the outer perimeter of the panel with a dispenser or the like and then hardening the fluid material. 
         [0007]    Also, a layer (substrate layer) in which a plurality of the flexible element substrates and counter substrates are arranged is formed on a support plate such as a glass substrate, and after the two substrates are bonded together on each support plate, the resulting structure is divided into a plurality of display panels. 
       SUMMARY OF THE INVENTION 
       [0008]    In order to achieve a narrow frame on a high-definition display panel, a dam needs to be patterned with a smaller width and higher precision. However, with the technique of dripping the dam material from the nozzle of the dispenser, high-precision patterning is difficult. 
         [0009]    Also, the dam material dripped from the dispenser and hardened is relatively flexible and will not easily crack. Therefore, when dividing the integrally formed plurality of display panels into the individual display panels, laser cutting or the like is used, and a relatively simple technique such as scribe and break cannot be used. 
         [0010]    The invention is to provide a display panel which can be processed with higher precision by a simpler technique, when producing display panels by a so-called multiple formation, that is, stacking a substrate disposed a plurality of element substrates and a substrate disposed a plurality of counter substrates and then dividing the stacked substrate into a plurality of display panel, and in which the frame can be narrowed by reducing redundant areas between the substrates, and a manufacturing method thereof. 
         [0011]    A display device according to an aspect of the invention includes: an element substrate including a flexible multilayer structure having a resin film as a base member, and having a display area where a display element is formed; a counter substrate including a flexible multilayer structure having a resin film as a base member, and stacked on the display area of the element substrate; and a filler filling a space between the element substrate and the counter substrate. Each of the element substrate and the counter substrate has a rib which includes a covalently or ionically bonding inorganic material and which is in contact with an outer peripheral lateral surface of the multilayer structure. 
         [0012]    A manufacturing method of a display device according to another aspect of the invention is a manufacturing method of a display device having a flexible element substrate including a display area where a display element is formed, and a flexible counter substrate bonded to the display area of the element substrate with a filler held between the substrates. The manufacturing method includes: forming a first substrate layer in which a plurality of the element substrate is arranged, on one main surface of a first support plate; forming a second substrate layer in which the counter substrate is provided at each position facing the display area of each of the element substrates in the first substrate layer, on one main surface of a second support plate; bonding the first substrate layer on the first support plate to the second substrate layer on the second support plate and thus forming a substrate layer joined body; and dividing the first substrate layer together with the first support plate, dividing the second substrate layer together with the second support plate, and thereby dividing the substrate layer joined body held between the first and second support plates, into a plurality of parts, each part corresponding to the display device. The forming of the first substrate layer includes forming a ridge-like first rib including a covalently or ionically bonding inorganic material along an edge of the element substrate. The forming of the second substrate layer includes forming a counter area part made of a material including a flexible resin film and arranged opposite the display area, and a second rib including a covalently or ionically bonding inorganic material and in the form of a ridge surrounding the counter area part and higher than the counter area part. The bonding includes filling, with a filler, a recess part in the second substrate layer generated at the counter area part due to a height difference from the second rib. The dividing includes scribing the first and second support plates along the first and second ribs, and flexing and breaking the first and second support plates that are scribed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a schematic view showing a schematic configuration of an organic EL display device according to an embodiment of the invention. 
           [0014]      FIG. 2  is a schematic vertical cross-sectional view of a display panel according to the embodiment of the invention. 
           [0015]      FIG. 3  is a schematic process flowchart of the manufacturing method of the organic EL display device according to the embodiment of the invention. 
           [0016]      FIG. 4  is a schematic vertical cross-sectional view of each of a first substrate layer after the completion of a first substrate layer forming process, and a second substrate layer after the completion of a second substrate layer forming process. 
           [0017]      FIG. 5  is a schematic vertical cross-sectional view of the state where the first substrate layer and the second substrate layer are bonded together. 
           [0018]      FIG. 6  is a schematic plan view of the first substrate layer and the second substrate layer. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    Hereinafter, a form of embodying the invention (hereinafter referred to as an embodiment) will be described with reference to the drawings. 
         [0020]    The disclosure is only an example, and as a matter of course, any change that can be easily thought of by a person skilled in the art without departing from the spirit of the invention should be included in the scope of the invention. In order to clarify the explanation, the drawings may schematically show each part in terms of its width, thickness, shape and the like, compared with the actual configuration. However, this is simply an example and should not limit the interpretation of the invention. Also, elements similar to those described before with reference to already mentioned drawings may be denoted by the same reference signs, and detailed description of these elements may be omitted when appropriate. 
         [0021]    The display device according to the embodiment of the invention is an organic EL display device. The organic EL display device is an active-matrix display device and is installed in a television, personal computer, mobile terminal, mobile phone and the like. 
         [0022]      FIG. 1  is a schematic view showing a schematic configuration of an organic EL display device  2  according to the embodiment. The organic EL display device  2  has a pixel array part  4  which displays an image, and a drive unit which drives the pixel array part  4 . The organic EL display device  2  is a flat panel display and has a display panel. The display panel includes a display area where the pixel array part  4  is arranged, and a non-display area. 
         [0023]    In the pixel array part  4 , an OLED  6  as a display element and a pixel circuit  8  are arranged in the form of a matrix corresponding pixels. The pixel circuit  8  is made up of a plurality of TFTs  10 ,  12  and a capacitor  14 . 
         [0024]    Meanwhile, the drive unit includes a scanning line drive circuit  20 , a video line drive circuit  22 , a drive power-supply circuit  24 , and a control device  26 . The drive unit drives the pixel circuit  8  to control the light emission of the OLED  6 . 
         [0025]    The drive unit can be arranged in the non-display area of the display panel. The drive unit can be formed on the element substrate forming the display panel together with the pixel circuit  8 . Also, the drive unit may be put in an integrated circuit (IC) produced separately from the pixel circuit  8 , and this IC may be installed within the display panel or on a flexible printed circuit (FPC) connected to the display panel. 
         [0026]    The scanning line drive circuit  20  is connected to a scanning signal line  28  provided for each horizontal line of pixels (pixel row). The scanning line drive circuit  20  sequentially selects a scanning signal line  28  in response to a timing signal inputted from the control device  26 , and applies a voltage to switch on the lighting TFT  10 , to the selected scanning signal line  28 . 
         [0027]    The video line drive circuit  22  is connected to a video signal line  30  provided for each vertical line of pixels (pixel column). The video line drive circuit  22  has a video signal inputted from the control device  26 , and outputs a voltage corresponding to the video signal for the selected pixel row to each video signal line  30 , simultaneously with the selection of the scanning signal line  28  by the scanning line drive circuit  20 . This voltage is written in the capacitor  14  via the lighting TFT  10 , in the selected pixel row. The drive TFT  12  supplies a current corresponding to the written voltage to the OLED  6 , and this causes the OLED  6  of the pixel corresponding to the selected scanning signal line  28  to emit light. 
         [0028]    The drive power-supply circuit  24  is connected to a drive power-supply line  32  provided for each pixel column, and supplies a current to the OLED  6  via the drive power-supply line  32  and the drive TFT  12  in the selected pixel row. 
         [0029]    Here, the anode of the OLED  6  is connected to the drive TFT  12 . Meanwhile, the cathode of each OLED  6  is basically connected to the ground potential, and the cathodes of the OLEDs  6  of all the pixels are formed by a common electrode. 
         [0030]      FIG. 2  is a schematic vertical cross-sectional view of a display panel  40 . The display panel  40  includes an element substrate  42  and a counter substrate  44  bonded to each other. 
         [0031]    The element substrate  42  has a display area  46  and a non-display area  48 . In the display area  46  of the element substrate  42 , the pixel array part  4  is provided as already described. In the non-display area  48 , a wiring  50  led out of the pixel array part  4  in the adjacent display area  46  is formed. Also, in the non-display area  48 , a terminal  52  for connecting the drive unit to the wiring  50  or a circuit of the drive unit can be formed, and an IC can be arranged.  FIG. 2  shows an example in which an FPC  54  is connected to the terminal  52  provided in the non-display area  48 . 
         [0032]    The pixel array part  4 , the wiring  50 , the terminal  52  and the like are formed on one main surface of a base member  56  made of a flexible resin film. For example, the base member  56  can be formed using polyimide, epoxy, acrylic, polyethylene naphthalate, and a thermoplastic fluorine resin such as tetrafluoroethylene-ethylene copolymer. 
         [0033]    The pixel array part  4  has a multilayer structure including a circuit layer in which electronic circuits such as the pixel circuit  8 , the scanning signal line  28 , the video signal line  30 , and the drive power-supply line  32  are formed, and an OLED layer in which an OLED is formed, or the like. The OLED layer includes a pixel electrode, an organic material multilayer part, a common electrode, and a bank. The pixel electrode, the common electrode, and the organic material multilayer part held between these electrodes form the OLED. Also, basically, the common electrode contacts the organic material multilayer parts of all the pixels in the display area. Meanwhile, the pixel electrode is formed separately for each pixel and is connected to the drive TFT  12  shown in  FIG. 1  and formed in the circuit layer. The common electrode and the pixel electrode is formed using a transparent conductive material such as IZO (indium zinc oxide) or ITO (indium tin oxide). The organic material multilayer part has a light emitting layer. The light emitting layer has holes and electrons injected therein in response to the voltage applied to both electrodes, and emits light due to the recombination of these holes and electrons. 
         [0034]    The OLED layer is stacked on the circuit layer, and a cover layer  58  is stacked on the OLED layer. The cover layer  58  is made of a film with a moisture-proof function and protects the OLED from property deterioration due to moisture. For example, a layer made of silicon nitride (SiN) is stacked as the cover layer  58 . 
         [0035]    An end part  60  made of a covalently bonding inorganic material or an ionically bonding inorganic material is in tight contact with the outer peripheral lateral surface of the base member  56 . The end part  60  has a moisture-proof function on the lateral surface of the base member  56  or the like. Also, the back side of the element substrate  42 , that is, the side opposite to the side where the pixel array part  4  is formed, of the base member  56 , is covered by a barrier layer  62  having a moisture-proof function. 
         [0036]    The counter substrate  44  is stacked on the display area  46  of the element substrate  42 . The counter substrate  44  has a counter area part which is arranged opposite the display area  46 , and an end part  64  which surrounds the counter area part and is higher than the counter area part. The counter area part has a multilayer structure using a flexible resin film as a base member  66 , and a color filter and a barrier layer (hereinafter these two are collectively referred to as a color filter layer  68 ) and the like are stacked on one main surface of the base member  66 . The base member  66  can be formed using the materials mentioned above with respect to the base member  56 , for example. The end part  64  is made of a covalently bonding inorganic material or an ionically bonding inorganic material and is in tight contact with the outer peripheral lateral surface of the base member  66 . The end part  64  has a moisture-proof function on the lateral surface of the base member  66  and the like. Also, the back side of the counter substrate  44 , that is, the side opposite to the side where the color filter layer  68  is formed, of the base member  66 , is covered by a barrier layer  70  having a moisture-proof function. 
         [0037]    In the element substrate  42 , the cover layer  58  may cover the base member  56  in an area excluding the wiring  50 , of the non-display area  48 . Also, an underlying layer made up of a silicon nitride film and a silicon oxide film may be provided between the pixel array part  4  and the base member  56 , and this underlying layer may exist in the entirety of the display area  46  and the non-display area  48 . Since the cover layer  58 , the end part  60 , the barrier layer  62 , and the underlying layer, which do not easily pass oxygen or moisture through, are thus provided on the top surface, the bottom surface, and the lateral surface of the base member  56 , moisture or oxygen does not enter the base member  56 . Similarly, in the base member  66  of the counter substrate  44 , since the color filter layer  68 , the end part  64 , and the barrier layer  70 , which do not easily pass moisture or oxygen through, are provided on the top surface, the bottom surface, and the lateral surface, moisture or oxygen does not enter the base member  66 . 
         [0038]    The element substrate  42  and the counter substrate  44  are bonded together in such a way that the surface where the pixel array part  4  and the like are formed, of the element substrate  42 , and the surface where the color filter layer  68  is formed, face each other. Here, the surface where color filter layer  68  is formed, of the counter substrate  44 , is a recess part in the counter area part due to the height difference between the end part  64  and the counter area part. This recess part is filled with a filler  72  when bonding the two substrates  42 ,  44  together. The filler  72  fills the space between the element substrate  42  and the counter substrate  44  and hardens and thus bonds the two substrates together. 
         [0039]    In the part where the edge of the element substrate  42  and the edge of the counter substrate  44  coincide with each other, the top surface of the end part  60  and the top surface of the end part  64  face each other. In this part, the two substrate  42 ,  44  are in tight contact with each other, preventing the filler  72  from leaking out. Meanwhile, in the part where the edge of the counter substrate  44  and the edge of the element substrate  42  do not coincide with each other, specifically, in the boundary part between the display area  46  and the non-display area  48  of the element substrate  42 , a dam material  74  is stacked on the element substrate  42  in order to prevent the formation of a space between the top surface of the end part  64  and the top surface of the element substrate  42  and the entry of the filler  72  into the space. 
         [0040]    To protect the joined body of the element substrate  42  and the counter substrate  44 , protection films  76 ,  78  are bonded onto the outer surfaces of the substrates, that is, onto the barrier layers  62 ,  70 . 
         [0041]    Next, the manufacturing method of the organic EL display device  2  will be described. The manufacturing method of the organic EL display device  2  according to the invention is characterized by the manufacturing method of the display panel  40 . In this manufacturing method, the multilayer structures of a plurality of display panels  40  are formed integrally. 
         [0042]      FIG. 3  is a schematic process flowchart of the manufacturing method. This process flow is made up of a series of steps for forming a first substrate layer in which the structures of a plurality of element substrates  42  are arranged on one main surface of a first support plate (first substrate layer forming process: Steps S 10  to S 15 ), a series of steps for forming a second substrate layer in which the structure of each counter substrate  44  is provided at a position facing the display area  46  of each element substrate  42  in the first substrate layer, on one main surface of a second support plate (second substrate layer forming process: Steps S 20  to S 24 ), and a series of steps (Steps S 30  to S 33 ) for assembling the first substrate layer and the second substrate layer into the display panel  40 . 
         [0043]      FIG. 4  is a schematic vertical cross-sectional view of the first substrate layer after the completion of the first substrate layer forming process and the second substrate layer after the completion of the second substrate forming process. In this illustration, the direction of and horizontal positional relation between the two substrate layers are the same as those at the time of bonding these substrate layers.  FIG. 5  is a schematic cross-sectional view of the state where the two substrate layers are bonded together. 
         [0044]      FIG. 6  is a schematic plan view of a first substrate layer  200  and a second substrate layer  202 . The position of the cross section shown in  FIGS. 4 and 5  is the same as in  FIG. 2 , and this position is indicated by a segment A-A in  FIG. 6 . In  FIG. 6 , one element substrate  42  arranged in the first substrate layer  200  and one counter substrate  44  arranged in the second substrate layer  202  are indicated by hatching. The element substrate  42  has a rectangular planar shape. In  FIG. 6 , the area above the dotted line in this rectangle is the display area  46 , and the area below the dotted line is the non-display area  48 . The counter substrate  44  has a rectangular planar shape, too, and has a shape basically coincident with the display area  46  of the element substrate  42 . When the first substrate layer  200  and the second substrate layer  202  are bonded together, three sides of the four sides forming the outline of the counter substrate  44  overlap with the outline of the element substrate  42 , and the remaining one side is situated at the boundary between the display area  46  and the non-display area  48 . 
         [0045]    Since the element substrate  42  is flexible, a support plate  90  which holds the element substrate  42  in a flat state is prepared at the beginning of the first substrate layer forming process (Step S 10 ). As the support plate  90 , a material suitable for the scribe and break technique is used. For example, the support plate  90  is formed using glass. In this embodiment, in order to produce a plurality of display panels  40  in one shot as described above, the support plate  90  in a shape and size that allows a plurality of element substrate  42  to be arranged thereon is prepared. In the example shown in  FIG. 6 , three by three element substrates  42 , in the directions of length and width, are arranged on the support plate  90 . 
         [0046]    First, the first substrate layer forming process will be described. A sacrificial layer (not illustrated) used at the time of stripping the element substrate  42  from the support plate  90 , and the barrier layer  62  having a moisture-proof function are stacked in order on the support plate  90  (Step S 11 ). The sacrificial layer is preferably made of a metal or metal oxide. Titanium (Ti), tungsten (W) or oxides thereof may be used. The barrier layer  62  is made up of a silicon nitride film, silicon oxide film, silicon carbonitride film, silicon carbide film, or multilayer structure of these films. 
         [0047]    A ridge-like first rib  92  is formed using a covalently or ionically bonding inorganic material, on the barrier layer  62  along the edge of the element substrate  42  (Step S 12 ). In  FIG. 6 , the element substrate  42  is in contact with the edge of the adjacent element substrate  42 , and these element substrates  42  share the rib  92  provided along the side in the direction of length. Meanwhile, in the example of  FIG. 6 , since a margin area  94  is provided between the element substrates  42  next to each other in the direction of length, the rib  92  provided along the side in the direction of width of the element substrates  42  is not shared between the element substrates  42 . 
         [0048]    As a method for forming the rib  92 , patterning using a photolithography technique, a printing method, an aerosol deposition method, sheet pasting or the like can be used. Incidentally, the aerosol deposition method is a high-speed coating method in which fine particles of ceramics, metal or the like as a powder material are sprayed, thus enabling solidification and densification at room temperature without needing a binder or pre-heating of the base member. The rib  92  is formed of a covalently or ionically bonding inorganic material as described above, due to its characteristic of being susceptible to cracking, compared with an organic material like resin or a metal, and therefore suitable for the scribe and break technique. For example, the rib  92  is formed of SiN, silicon oxide (SiO), ITO or the like. Moreover, the same material as the sacrificial layer may be used for the rib  92 , and a metal oxide or metal nitride may be used. A material that can easily crack and does not easily pass water and oxygen through is preferable for the rib  92 . The thickness (height) of the rib  92  is set to be basically the same as or slightly greater than the thickness of the multilayer structure that is subsequently formed in the area surrounded by the rib  92 . 
         [0049]    In the area surrounded by the rib  92 , the base member  56  of the flexible resin film is stacked (Step S 13 ). Further thereon, the circuit layer of the pixel array part  4 , the OLED layer and the like are formed in the display area  46 , whereas the wiring  50 , the terminal  52  and the like are formed in the non-display area  48 , and the cover layer  58  is formed thereon (Step S 14 ). 
         [0050]    After the main structure of the element substrate  42  such as the pixel array part  4  and the wiring  50  is formed on the base member  56  in Step S 14 , the dam material  74  (seal part) having a thickness corresponding to the height difference between the position of the rib  92  and an area arranged opposite the end part  64  of the counter substrate  44  at the boundary between the display area  46  and the non-display area  48  is formed in this area (Step S 15 ). Thus, the first substrate layer  200  is formed on the surface of the support plate  90 . 
         [0051]    Next, the second substrate layer forming process will be described. In this process, as in the first substrate layer forming process, a support plate  96  is prepared (Step S 20 ), and a sacrificial layer (not illustrated) and the barrier layer  70  are stacked thereon in order (Step S 21 ). Also, a ridge-like second rib  98  is formed using a covalently or ionically bonding inorganic material, on the barrier layer  70  along the edge of the counter substrate  44  (Step S 22 ). The rib  98  can be formed using a technique and material that are basically similar to those of the rib  92 . The thickness (height) of the rib  98  is set to be basically greater than the thickness of the multilayer structure subsequently formed in the area (counter area part) surrounded by the rib  98 . The same material as the barrier layer  62  may be used for the barrier layer  70 , and the same material as the material used at the time of forming the first substrate layer may be used for the sacrificial layer. 
         [0052]    Also, in  FIG. 6 , since the counter substrate  44  is stacked on the display area  46  of the element substrate  42 , the counter substrates  44  next to each other in the direction of width are in contact with each other at the edge, similarly to the element substrates  42 , and these counter substrates  44  share the rib  98  provided along the side in the direction of length, whereas the rib  98  provided along the side in the direction of width is not shared between the counter substrates  44 . 
         [0053]    In the area surrounded by the rib  98 , the base member  66  of the flexible resin film is stacked (Step S 23 ), and the color filter, the barrier layer and the like forming the color filter layer  68  are formed further thereon (Step S 24 ). Thus, the second substrate layer  202  is formed on the surface of the support plate  96 . As described above, the same material as the base member  56 , for example, can be used for the base member  66 . 
         [0054]      FIG. 4  shows the first substrate layer  200  and the second substrate layer  202  produced by the above processes. Next, the process of assembling these substrate layers into the display panel  40 . The counter area part of the second substrate layer  202 , that is, the surface of the area surrounded by the rib  98 , is a recess part by having the rib  98  formed to be higher than the counter area part. This recess part is filled with the filler  72 , using a dispenser or the like (Step S 30 ). Then, for example, the support plate  96  is horizontally placed, with the surface where the second substrate layer  202  is formed facing upward, and the support plate  90  is overlaid on the support plate  96 , with the surface where the first substrate layer  200  is formed facing downward. Then, the first substrate layer  200  and the second substrate layer  202  are bonded together into the state shown in  FIG. 5  (Step S 31 ). 
         [0055]    Here, the filler  72  may fill the gap between the two substrate layers when the first substrate layer  200  and the second substrate layer  202  are bonded together. That is, the filler  72  need not necessarily be spread on the entire surface of the recess part at the stage of Step S 30 . For example, the filler  72  may be scattered inside the recess part in Step S 30 , and the filter  72  can be evenly spread in the gap when the two substrate layers are bonded in a vacuum. 
         [0056]    Also, a filler  100  may be scattered in the area opposite the margin area  94  of the first substrate layer  200 , of the second substrate layer  202 , and may be used as a spacer for maintaining the gap between the two substrate layers at the part corresponding to the non-display area  48  of the element substrate  42 . 
         [0057]    After the fillers  72 ,  100  are hardened, the joined body of the substrate layers  200 ,  202  is divided together with the support plates  90 ,  96  into the respective display panels  40  by using the scribe and break technique (Step S 32 ). Specifically, each of the support plates  90 ,  96  is scribed and the substrate layers are flexed and broken together with the support plates. 
         [0058]    Scribe lines are formed along the ribs  92 ,  98 . Particularly, at the part where the rib is shared among the element substrates  42  adjacent to each other in the first substrate layer  200 , or the counter substrates  44  adjacent to each other in the second substrate layer  202 , the scribe line is set within the width of the rib, so that the rib is left on both adjacent substrates after breaking. In this embodiment, such a shared part of the rib is the part extending in the direction of length, of the ribs  92 ,  98  shown in  FIG. 6 . 
         [0059]    Meanwhile, at the part of the rib that is not shared among the element substrates  42  adjacent to each other in the first substrate layer  200  or the counter substrates  44  adjacent to each other in the second substrate layer  202 , the scribe line may be set along the edge on the side of the rib that is not adjacent to the element substrate  42  or the counter substrate  44 , so that, at this part, the rib is left in its full width on the adjacent substrate. In this embodiment, such a non-shared part of the rib is the part extending in the direction of width, of the ribs  92 ,  98  shown in  FIG. 6 . However, the scribe line is set within the width of the rib at this part as well, thus achieving a narrower frame. Specifically, scribe lines are set at the positions α 1 , α 2  on the first substrate layer  200  and the positions β 1 , β 2  on the second substrate layer  202  shown in  FIG. 5 , and the substrate layers are then broken. 
         [0060]    The ribs  92 ,  98  after the breaking form the outer peripheral end parts  60 ,  64  of the element substrate  42  and the counter substrate  44 , respectively. 
         [0061]    Here, the dam material  74  is formed in the area facing a part of a rib  98   a  shown in  FIG. 5 . The rib  98   a  is the rib  98  situated at the boundary between the display area  46  and the non-display area  48 , and the part of the rib  98   a  belongs to the counter substrate  44  after the braking. That is, in the case where the scribe line is set within the width of the rib  98   a  as described above, the forming area for the dam material  74  and the position of the scribe line are adjusted so that the dame material  74  will not protrude to the outside from the position β 2  of the scribe line. If the dam material  74  is laid across the break position, the dame material  74  may not be divided, or a part  102  that should be removed by the division, of the second substrate layer  202 , may remain attached to the element substrate  42  even after the division. On the other hand, if the dam material  74  is held on the inside from the position β 2  of the scribe line, this part  102  can be easily removed by breaking. 
         [0062]    After the breaking, the cover layer  58  and the like stacked on the terminal  52  are removed, exposing the terminal  52 . Then, the process of connecting the FPC  54  to the terminal  52 , or the like, is carried out. 
         [0063]    Subsequently, the support plates  90 ,  96  are separated from the joined body of the element substrate  42  and the counter substrate  44  divided for each display panel  40  by the breaking (Step S 33 ). For the separation of the support plates, methods such as evaporating the sacrificial layers between the barrier layers  62 ,  70  and the support plates  90 ,  96  by laser ablation, or dissolving the sacrificial layers by etching, may be used. After separating the support plates, the protection films  76 ,  78  are stuck to the back sides of the element substrate  42  and the counter substrate  44 . Thus, the structure of the display panel  40  shown in  FIG. 2  is basically achieved. 
         [0064]    In the embodiment, the case of an organic EL display device is illustrated as a disclosed example of the display device. However, as other application examples, any flat panel display devices can be employed, such as a liquid crystal display device, other types of self-light-emitting display device, electronic paper display device having an electrophoretic element or the like, and quantum dot display device. Also, as a matter of course, display devices of medium and small sizes to large size can be used without any particular limitation. 
         [0065]    A person skilled in the art can readily think of various changes and modifications within the scope of the technical idea of the invention, and such changes and modifications should be understood as falling within the scope of the invention. For example, the addition or deletion of a component, or a design change suitably made to the foregoing embodiment by a person skilled in the art, or the addition or omission of a process, or a condition change in the embodiment is included in the scope of the invention as long as such change or the like includes the spirit of the invention. 
         [0066]    Also, as a matter of course, other advantageous effects that may be achieved by the configurations described in the embodiment should be understood as being achieved by the invention if those effects are clear from the specification or can be readily thought of by a person skilled in the art. 
         [0067]    While there have been described what are at present considered to be certain embodiments of the invention, it will be understood that various modifications may be made thereto, and it is intended that the appended claims cover all such modifications as fall within the true spirit and scope of the invention.