Abstract:
At a corner of a TFT substrate where sealants are coated overlapping each other, a phenomenon that the sealants protrude into the display region is prevented by a structure that: the TFT substrate having an organic passivation film is formed as far as the outside of the display region. A groove-like organic passivation film removed portion is formed surrounding the display region. Since the sealants are coated overlapping each other at the corner, when a TFT substrate and a counter substrate are superposed at a predetermined gap, the width of the groove-like organic passivation film removed potion is made larger at the corner than the side in order to prevent the sealant from extending. Since an excessive sealant is absorbed in the groove-like organic passivation film removing portion of a larger width at the corner, the sealant can be prevented from protruding to the inside of the display region.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 14/043,897 filed on Oct. 2, 2013, which claims priority from Japanese Patent Application No. 2012-220114 filed on Oct. 2, 2012, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a display device and it particularly relates to a liquid crystal display device that ensures the reliability of seal in spite of a narrow frame. 
     2. Description of the Related Art 
     A conventional liquid crystal display device includes a TFT substrate having a pixel electrode, thin film transistors (TFT), etc. formed in a matrix; a counter substrate disposed in facing relation to the TFT substrate and having a color filter, etc. formed at portions corresponding to the pixel electrodes of the TFT substrate; and liquid crystals put between the TFT substrate and the counter substrate. Images are formed by controlling the transmittance of light for every pixel by liquid crystal molecules. 
     Since the liquid crystal display devices are flat and light in weight, their application use has been extended in various fields. Small-sized liquid crystal display devices have been used generally for mobile phones, DSCs (Digital Still Cameras), etc. For the small-sized liquid crystal display devices, there is a strong demand for decreasing the outer dimension while ensuring a predetermined display region. Then, a distance between the end of the display region and the end of the outer contour, that is, a so-called, frame is narrowed. In this case, the area of a seal portion for sealing liquid crystals is decreased, resulting in a problem in ensuring the reliability of the seal portion. 
     It is inefficient to manufacture liquid crystal display panels on a one by one basis. Thus a method has been adopted of forming a plurality of liquid crystal display panels on a mother substrate, and then separating individual liquid crystal display panels from the mother substrate by scribing, etc. Further, as a method of sealing liquid crystals, a method of injecting liquid crystals through a sealing port has been used so far, but in this case it takes much time for injection of the liquid crystals. To cope with this, a so-called one drop fill (ODF) method has been adopted, in which a sealant is first formed to a TFT substrate or a counter substrate, and the liquid crystals are then sealed inside of the liquid crystal display panel while accurately controlling the amount of the liquid crystals in the inside of the sealant. 
     With the ODF method, the sealant is formed as a closed loop. While the sealant is coated by a dispenser or the like, portions of the sealant will overlap at the starting point and the end point of sealant coating, resulting in an increase in thickness of the sealant at the overlap portion. This may cause gap failure between the TFT substrate and the counter substrate or protrusion of the sealant toward the display region. 
     As a countermeasure for the problem with the sealant overlapping, JP-A-2010-145897 describes a configuration in which a recess is formed to an overcoat film formed to a counter substrate at portions corresponding to a starting point and an end point of the coated sealant, thereby absorbing an excessive sealant to the portion. 
     SUMMARY OF THE INVENTION 
     JP-A-2010-145897 describes a method in which a coated sealant forms a closed loop in one liquid crystal display panel and the overlap portion of the sealant is present at the side of the liquid crystal display panel. In the configuration of JP-A-2010-145897, a recess is formed to the overcoat film of the counter substrate only at a portion corresponding to the overlap portion of the sealant. 
     JP-A-2010-145897 does not describe clear effects obtained when the overlap portion of the sealant is formed at the corner of the counter substrate. In particular, when the sealant is coated on a plurality of TFT substrates on a mother TFT substrate in which a plurality of TFT substrates are formed as illustrated in  FIG. 5  of the present application, a cross portion of the sealants is formed at two positions on the liquid crystal display panel, but it is not certain whether the configuration described in JP-A-2010-145897 is applicable to such a configuration. Further, in the configuration of JP-A-2010-145897, it is necessary to partially cut out the periphery of an overcoat film. While general overcoat films can be formed by merely coating and curing, the overcoat film provided in JP-A-2010-145897 has to be formed with recessed portion by applying photolithography to the overcoat film resulting in increase the cost. 
       FIG. 5  illustrates an example of a coating configuration of a sealant  10  to a TFT substrate  100  on a mother TFT substrate to which the invention is applied. In  FIG. 5 , a dotted line indicates a boundary for a portion where a counter substrate is disposed when a liquid crystal display panel is in a completed state. A portion below the dotted line is a portion where one sheet of the TFT substrate is present, serving as a terminal portion  150 . The sealant  10  is formed at the periphery where a TFT substrate and a counter substrate overlap each other. 
     The configuration of the sealant in  FIG. 5  has such a shape that the sealant  10  can be coated continuously by a dispenser or the like to a plurality of TFT substrates on a mother TFT substrate. For example, one sealant is coated in a U-shaped configuration along a cut line  50  of the TFT substrate from the right and then another sealant  10  is coated in an inverted U-shape configuration from the left. At portions C in  FIG. 5 , two sealants  10  are formed in an overlapping manner. With such a coating method, the sealant can be coated efficiently to a mother TFT substrate having many TFT substrates formed therein or to a mother counter substrate having many counter substrates formed therein. 
     In this case, the width of the sealant  10  increases in the overlap portion of the counter substrate and the TFT substrate. In  FIG. 5 , two sealants  10  are formed on both sides of the cut line  50  along the longer side. After coated on the TFT substrate, the sealants  10  are pressed to bond the TFT substrate and the counter substrate each other so as to define a predetermined gap and thus the sealants  10  are extended. As a result, the sealants  10  are formed over the cut line  50 . 
     A display region  30  is formed inside of the coated sealant  10 . A distance from the end of the display region  30  to the cut line  50  of the TFT substrate, that is, the width of a so-called frame is, for example, D 1 =0.8 mm at the longer side, D 3 =2.3 mm at the shorter side on the side of the terminal, and D 2 =1.0 mm at the shorter side opposite to the terminal. In a conventional manner for coating the sealant as above, a sealing failure has occurred as follows. The sealant  10  protrudes to the display region  30  from the overlap portion of the sealants  10  in the corner portion. 
       FIG. 6  is a plan view near the cut line  50  at the corners of each TFT substrates on a mother TFT substrate. An organic passivation film  109  is formed as far as the outside of the display region  30 . A peripheral circuit  40  such as a scanning line driving circuit is formed below the organic passivation film  109  at the outside of the display region  30 . In  FIG. 6 , hatched portions show removed portions  20  of the organic passivation film. 
     The organic passivation film removed portions  20  are formed as three grooves at the periphery of the display region  30 . Further, the organic passivation film removed portions  20  are formed each at a predetermined width with the cut line  50  of the individual TFT substrate being put therebetween. In  FIG. 6 , a portion indicated by a dotted line is a portion in which the sealant  10  is to be formed. As shown in  FIG. 6 , two sealants  10  overlap each other at the corners of the TFT substrates. 
       FIG. 7  is a cross sectional view along line B-B in  FIG. 6 . While  FIG. 7  is a simplified cross sectional view, a detailed cross sectional view is to be described specifically in  FIG. 1 . In  FIG. 7 , an organic passivation film  109  is formed over a TFT substrate  100 . Layers below the organic passivation film  109  are not illustrated. Organic passivation film removed portions  20  are formed to the organic passivation film  109  and each portion is formed as a groove. The end of the TFT substrate is formed as an organic passivation film removed portion  20 . An inorganic insulation film  111  made of SiN, etc. is formed to cover the organic passivation film  20 . 
     The TFT substrate  100  and the counter substrate  200  are bonded by a sealant  10 , and liquid crystals  300  are sealed inside the sealant  10 . In  FIG. 7 , the TFT substrate  100  and the counter substrate  200  are superposed with a predetermined gap formed between them in which the sealant  10  is in a pressed state. If the width of the sealant  10  increases a predetermined dimension or more when the sealant  10  is pressed, this may cause a failure that the sealant  10  protrudes to the display region. 
     In the TFT substrate  100  and the counter substrate  200 , formed at the surface in contact with liquid crystals  300  is an alignment film which is not illustrated. When the alignment film is present between the sealant  10  and an inorganic insulation film  111 , bonding strength of the sealant  10  is lowered. To deal with the deterioration of the sealant  10  mentioned above, as shown in  FIG. 7 , an organic passivation film removed portions  20  are formed in a groove shape and serve as dams for preventing the alignment film from flowing out to the outside. A portion A in  FIG. 7  shows that such three dams are formed. 
     In  FIG. 7 , since neither the alignment film nor the organic passivation film  109  is formed in a portion B, bonding strength between the sealant  10  and the TFT substrate  100  is great and the reliability of the seal can be ensured at the portion. As shown in  FIG. 6  and  FIG. 7 , the width of the groove-like organic passivation film removed portion  20  has a width which is identical between the side and the corner. This is because the main purpose of the groove-like organic passivation film removed portions  20  is to provide a dam to the alignment film. 
       FIG. 8  is a plan view illustrating the state in which the width of the sealant  10  is enlarged at an overlap portion of the sealants  10 , and the sealant  10  protrudes as far as the display region  30  as indicated by C in  FIG. 5 .  FIG. 8  illustrates the presence of a sealant protrusion portion  31  in which a portion of the sealant  10  protrudes to the display region  30 . Such a liquid crystal display panel is defective. 
     The subject of the present invention is to prevent the sealant from protruding to the display region while ensuring the reliability of the seal in a liquid crystal display panel having a narrowed frame. 
     The present invention intends to overcome the problems described above and specifically comprises the following configurations. That is, the present invention provides a liquid crystal display device comprising a TFT substrate including a region for display and having an organic passivation film formed thereover, a counter substrate disposed with a sealant formed in a seal portion between the TFT substrate and the counter substrate, and liquid crystals put between the TFT substrate and the counter substrate, in which, the organic passivation film is formed as far as the outside of a display region of the TFT substrate, the organic passivation film having a groove-like organic passivation film removed portion surrounding the display region in the seal portion, the width of the groove-like organic passivation film removed portion being larger at the corner than at the side, a peripheral circuit is formed in the seal portion of the TFT substrate, and a gap between the TFT substrate and the counter substrate in the seal portion is defined by a pillar spacer formed on the counter substrate and a pedestal of the organic passivation film formed over the TFT substrate. 
     According to the present invention, when sealant is formed to each of the TFT substrates in the mother TFT substrate, since the width of the groove-like organic passivation film removed portion also that serves as a dam for the alignment film is enlarged at the corner than at the side, even if the sealants are formed overlapping each other in the portion, the sealants do not protrude to the display region. 
     Further, when a peripheral driving circuit is formed in a layer below the organic passivation film removed portion, since the gap between the TFT substrate and the counter substrate at the seal portion is controlled by using a pillar spacer formed on the side of the counter substrates with the organic passivation film at a portion other than the organic passivation film removed portion being as a pedestal, the peripheral driving circuit is not injured. 
     Further, in the present invention, since no additional photolithographic step is necessary for preventing protrusion of the sealant at the corner, the cost does not increase when the invention is applied. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view of a liquid crystal display device having a common electrode top structure to which the present invention is applied; 
         FIG. 2  is a plan view illustrating a relation between a pixel electrode and a common electrode; 
         FIG. 3  is a plan view for the corner of a TFT substrate in the invention; 
         FIG. 4  is a cross-sectional view along line A-A in  FIG. 3 ; 
         FIG. 5  illustrates a configuration of coating a sealant in the liquid crystal display device to which the invention is applied; 
         FIG. 6  is a plan view of a corner in a TFT substrate in a conventional embodiment; 
         FIG. 7  is a cross sectional view along line B-B in  FIG. 6 ; and 
         FIG. 8  is a plan view illustrating a state in which a sealant protrudes to a display region. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is to be described specifically by way of preferred embodiments. 
     First Embodiment 
       FIG. 1  is a cross sectional view of an IPS pixel region of a common electrode top structure to which the invention is applied. TFT in  FIG. 1  is a so-called top gate TFT. As a semiconductor, LTPS (Low Temperature Poly-Si) is used. In addition to the common electrode top structure, IPS of a pixel electrode top structure is also present, to which the invention is also applicable. 
     On the other hand, when an a-Si semiconductor is used, a so-called bottom gate TFT is often used. In the subsequent description, while the top gate TFT is to be described as an example, the invention is applicable also to a case of using the bottom gate TFT. Also in a case of using the bottom gate TFT, the invention is applicable to any of a common electrode top type or a pixel electrode top type. 
     In  FIG. 1 , a first underlayer film  101  made of SiN and a second underlayer film  102  made of SiO 2  are formed over a glass substrate  100  by CVD (Chemical Vapor Deposition). The first underlayer film  101  and the second underlayer film  102  serve to prevent impurities in the glass substrate  100  from contaminating a semiconductor layer  103 . 
     The semiconductor layer  103  is formed over the second underlayer film  102 . The semiconductor layer  103  is provided by forming an a-Si film over a second underlayer film  102  by CVD and converting the a-Si film into a poly-Si film by laser annealing. The poly-Si film is patterned by photolithography. 
     A gate insulating film  104  is formed over the semiconductor film  103 . The gate insulation film  104  is an SiO 2  film formed from TEOS (tetraethoxy silane). The film is also formed by CVD. A gate electrode  105  is formed over the insulation film  104 . The gate electrode  105  is formed in the same layer and at the same time as a scanning signal line. The gate electrode  105  is formed, for example, of an MoW film. An Al alloy is used when it is necessary to lower the resistance of the gate interconnect  105 . 
     The gate electrode  105  is patterned by photolithography and, during patterning, impurities such as phosphorus or boron are doped in the poly-Si layer to form a source S or a drain D in the poly-Si layer by ion implantation. Further, a LDD (Lightly Doped Drain) layer is formed between the channel layer of the poly-Si layer and the source S or the drain D by utilizing a photoresist upon patterning the gate electrode  105 . 
     Then, a first interlayer insulation film  106  is formed by SiO 2  covering the gate electrode  105  or a gate interconnect. The first layer insulation film  106  is formed for insulating the gate interconnect  105  and a source electrode  107 . A through hole  120  is formed in the first interlayer insulation film  106  and the gate insulation film  104  for connecting the source S of the semiconductor layer  103  and the source electrode  107 . Photolithography for forming the through hole  120  in the first interlayer insulation film  106  and the gate insulation film  104  is performed simultaneously. 
     The source electrode  107  is formed over the first insulation film  106 . The source electrode  107  is connected to a pixel electrode  112  by way of the through hole  130 . In  FIG. 1 , the source electrode  107  is formed in a wide area so as to cover the TFT. On the other hand, the drain D of the TFT is connected to a drain electrode in a not illustrated portion. 
     The source electrode  107 , the drain electrode, and a video signal line are formed in the same layer and at the same time. For example, an AlSi alloy is used for the source electrode  107 , the drain electrode, and the video signal line (hereinafter typically represented by the source electrode  107 ) in order to lower the resistance. Since the AlSi alloy generates hillock or Al diffuses into other layers, a structure of sandwiching AlSi with a not illustrated barrier layer and a cap layer made of MoW is adopted. 
     An inorganic passivation film (insulation film)  108  is formed to cover the source electrode  107  to protect the entire TFT. The inorganic passivation film  108  is formed by CVD in the same manner as the first underlayer film  101 . An organic passivation film  109  is formed to cover the inorganic passivation film  108 . The organic passivation film  109  is formed of a photosensitive acrylic resin. The organic passivation film  109  can be formed, for example, of silicone resin, epoxy resin, polyimide resin, etc. in addition to the acrylic resin. Since the organic passivation film  109  serves as a planarization film, the film  109  is formed to have a large thickness. The thickness of the organic passivation film  109  is 1 to 4 μm and is about 2 μm in most cases. 
     For establishing electric conduction between the pixel electrode  110  and the source electrode  107 , a through hole  130  is formed in the inorganic passivation film  108  and the organic passivation film  109 . A photosensitive resin is used for the organic passivation film  109 . After coating of a photosensitive resin, when the resin is exposed, only the portion exposed to light is dissolved in a predetermined developer. That is, formation of a photoresist can be saved by using the photosensitive resin. After the through hole  130  is formed in the organic passivation film  109 , the organic passivation film is baked at about 230° C. to complete the organic passivation film  109 . 
     In the invention, the organic passivation film extends as far as the seal portion of the liquid crystal display panel and the organic passivation film removed portion is formed in a groove-like shape at the seal portion so that the film serves as a dam that prevents the alignment film from flowing to the outside. Further, in the invention, the width of the groove of the organic passivation film removed portion is made larger at the corner than at the side thereby preventing the sealants from protruding to the display region when the sealant are coated being overlapped each other. 
     A through hole is formed in the inorganic passivation film  108  by etching using the organic passivation film  109  as a resist. Thus, a through hole  130  for electric conduction between the source electrode  107  and the pixel electrode  110  is formed. Since the inorganic passivation film  108  is etched using the patterned organic passivation film  109  as a resist, it is not necessary to use an additional mask and the photolithographic step can be performed by one step. Since the organic passivation film  109  has a large thickness, the dimension of the hole is different between the upper part and the lower part of the through hole  130 . 
     In  FIG. 1 , the upper surface of the thus formed organic passivation film  109  is planar. Amorphous ITO (Indium Tin Oxide) is deposited by sputtering over the organic passivation film  109 , patterned by using a photoresist, and then etched with oxalic acid to pattern a pixel electrode  112 . The pixel electrode  112  is formed also covering the through hole  130 . The pixel electrode  112  is formed of ITO as a transparent electrode and has a thickness, for example, of 50 to 70 nm. 
     Then, a second interlayer insulation film  111  is deposited covering the pixel electrode  112  by CVD. The CVD is performed under the condition of temperature at about 200° C., so this CVD is referred to as low temperature CVD. The low temperature CVD is used for preventing denaturation of the already formed organic passivation film  109 . 
     The second interlayer insulation film  111  is patterned by a photolithographic step in which the patterning is performed for a terminal portion and patterning for the through hole region is not necessary. 
     Amorphous ITO is sputtered over the second interlayer insulation film  111 , and a comb-shaped common electrode  110  is formed by a photolithographic step. The thickness of the common electrode  110  is, for example, about 30 nm. The common electrode  110  is formed thinly so as to prevent alignment failure by rubbing shadow when the alignment film  113  formed over the common electrode  110  is applied with rubbing. 
       FIG. 2  is a plan view illustrating a relation between the comb-shaped common electrode  110  and the pixel electrode  112  coated in a solid form. In  FIG. 2 , the common electrode  110  is disposed above the pixel electrode  112  with a not illustrated second interlayer insulation film being put therebetween. As illustrated in  FIG. 1 , lines of electric force extend from the upper surface of the common electrode  110  through slits  115  in the comb-shaped common electrode  110  to the pixel electrode  112  and liquid crystal molecules are rotated by the lines of electric force. 
     In  FIG. 1 , both the pixel electrode  112  and the common electrode  110  are formed in the region of the through hole  130 . Accordingly, a light transmitting region can be formed also to the upper end of the through hole  130  or the inner wall of the through hole  130  when the liquid crystal molecules  301  can be aligned properly. Accordingly, compared with a pixel electrode top structure, the pixel region can be used more efficiently for forming images. 
     In  FIG. 1 , a counter substrate  200  is provided with the liquid crystal layer  300  being sandwiched between the substrates. A color filter  201  is formed to the inner side of the counter substrate  200 . As the color filter  201 , color filters of red, green, and blue are formed on every pixels to form color images. A black matrix  202  is formed between adjacent color filters  201  to improve the contrast of images. The black matrix  202  also serves as a light shielding film for the TFT to prevent photocurrent from flowing to the TFT. 
     An overcoat  203  is formed to cover the color filter  201  and the black matrix  202 . Specifically, since each of the color filter  201  and the black matrix  202  has an uneven surface, the overcoat film  203  is adapted to have a flat surface. An alignment film  113  is formed over the overcoat film  203  for determining initial alignment of liquid crystals. Since  FIG. 2  illustrates an IPS system, the common electrode is formed on the side of the TFT substrate  100  and not formed on the side of the counter substrate  200 . 
     As illustrated in  FIG. 1 , a conduction film is not formed to the inner side of the counter substrate  200  in IPS. Then, the potential of the counter substrate  200  becomes instable. Further, external electromagnetic noises intrude to the liquid crystal layer  300  to give an undesired effect on images. For overcoming such a problem, an external conductive film  210  is formed to the outside of the counter substrate  200 . The external conductive film  210  is formed by sputtering ITO, which is a transparent conductive film. 
       FIG. 3  is a plan view near cut lines  50  at corners of individual TFT substrates on a mother TFT substrate in the invention. The organic passivation film  109  is formed as far as the outside of the display region  30 . A peripheral circuit  40  such as a scanning line driving circuit is formed below the organic passivation film  109  at the outside of the display region  30 . In  FIG. 3 , hatched portions are the organic passivation film removed portions  20 . 
     The organic passivation film removed portions  20  are formed as two grooves at the periphery of the display region  30 . In  FIG. 3 , the width of the grooves of the inner organic passivation film removed portions  20  is larger at corner than at side. In  FIG. 3 , the groove-like organic passivation film removed portions  20  are indicated only to portions of the TFT substrate, but the portions are actually formed surrounding the entire display region  30 . 
     In  FIG. 3 , portions indicated by dotted lines are portions where the sealants  10  are formed. As illustrated in  FIG. 3 , two sealants  10  overlap each other at the corners of the TFT substrates. While the width of the sealant  10  is larger in the overlap portion of the two sealants  10 , since the width of the grooves of the organic passivation film removed portions  20  are larger at the corners, protrusion of the sealant  10  to the display region  30  can be prevented also in the overlap portion of the sealants  10 . Also in the invention, the groove-like organic passivation film removed portions  20  also serve as dams for preventing the alignment film from flowing to the outside. 
       FIG. 4  is a cross-sectional view along line A-A in  FIG. 3 . In  FIG. 4 , an organic passivation film  109  is formed over a TFT substrate  100 . While layers as illustrated in  FIG. 1  are formed below the organic passivation film  109 , such layers are not illustrated in  FIG. 4 . 
     An organic passivation film removed portions  20  are formed in the organic passivation film  109  and the portions form grooves. The groove-like organic passivation film removed portions  20  are formed by the number of two and the portions serve as dams for preventing the alignment film from flowing to the outside. In this embodiment, the width of the inner groove on the of the two grooves is made larger at the corner so that protrusion of the sealant  10  does not reach the display region  30  even when the sealants  10  are formed being overlapped each other. 
     The end of the TFT substrate  100  forms the organic passivation film removed portion  20 . An inorganic passivation film  111  formed of SiN or the like is formed to cover the organic passivation film  109 . The region A shown by a dotted line in  FIG. 4  is a portion where groove-like passivation film removed portions  20  are formed which serve, in the invention, as dams for preventing the alignment film from flowing to the outside and preventing the sealant  10  from protruding into the display region  30  at a portion where the sealants  10  are coated overlap each other. 
     A dotted region B in  FIG. 4  is an organic passivation film removed portion  20  and, since only the inorganic insulation film  111  is present, bonding strength between the sealant  10  and the TFT substrate  100  is strong to improve the reliability of the seal portion. 
     A pillar spacer  60  is formed from the counter substrate  200  for defining the gap between the TFT substrate  100  and the counter substrate  200  at the seal portion. While a black matrix, a color filter, an overcoat film, etc. are formed below the pillar spacer  60  in the counter substrate  200 , they are not illustrated in  FIG. 4 . The gap between the TFT substrate  100  and the counter substrate  200  at the seal portion has been defined so far by glass fibers. However, in this embodiment, the peripheral circuit  40  is formed at the seal portion on the side of the TFT substrate  100 . When the groove-like organic passivation film removed portion  20  is formed with a large width at the corner, the peripheral circuit  40  may possibly be damaged by glass fibers or beads at the portion. 
     In the invention, as illustrated in  FIG. 4 , since the gap between the TFT substrate  100  and the counter substrate  200  at the seal portion  10  is defined not by using the glass fibers, beads, etc. but by the pillar spacer  60  on the organic passivation film  109  being as a pedestal, a not illustrated peripheral circuit  40  formed below the organic passivation film  109  undergoes no damages. 
     Further, in the present invention, since the groove of the organic passivation film removed portion  20  for preventing the alignment film from flowing to the outside is used also as a concave portion for preventing the sealant  10  from protruding to the display region  30  in the overlap portion thereof, there is no requirement for additional step for practicing the configuration of the invention. It may suffice to merely change the mask for forming the groove-like organic passivation film removed portion  20  compared with the conventional case. 
     In  FIGS. 3 and 4 , while two groove-like organic passivation film removed portions  20  are used, they may be one or three or more. Importance is attached in that the width of the groove-like organic passivation film removed portions  20  are made larger near the corner where the coated sealants  10  overlap each other than that at the side. The width of the grooves of the organic passivation film removed portion  20  is preferably three times or more larger at the corner than at the side. 
     In  FIG. 3 , also a trigonal organic passivation film  109  is present at the corners of each of the TFT substrates partitioned by cut lines  50 , that is, the organic passivation film  109  is present at the outermost portion in  FIG. 4  can also be removed in accordance with the protrusion amount of the sealant  10 . 
     In  FIG. 5 , since the sealants  10  cross at the upper left corner and at the lower right corner of the TFT substrate, the width of the organic passivation film removed portion  20  is made larger than that at the side. However, since the sealants  10  do not cross at the upper right corner and the lower right corner, the width of the organic passivation film removed portions  20  at the upper right corner and the lower right corner may be made identical with the width at the side. In this case, the peripheral circuit  40  can be protected more widely by the organic passivation film  109  than in the upper left corner and the lower right corner where the sealants  10  cross each other. 
     In the foregoing description, it has been described that the organic passivation film is removed completely with the organic passivation film removed portions  20 , but the organic passivation film  109  can be left thinly by using a half tone exposure technique to the organic passivation film removed portions  20 . In this case, the peripheral circuit  40  can be protected by the thin organic overcoat film that remains in the removed portion while suppressing protrusion of the sealant  10 .