Abstract:
The present invention relates to an organic electroluminescence display and a fabricating method thereof enabling to simplify a manufacturing process and reduce a product cost by separating devices with a single insulating pattern. The present invention includes the steps of: forming a plurality of stripe type first electrodes on a substrate; forming an insulating layer on the substrate including the first electrodes; forming a lattice type first insulating pattern on a first area crossing with the first electrodes and a second area between the first electrodes by patterning the insulating layer; forming a second insulating pattern by removing an upper portion of a part of the first insulating pattern on the first area at least and an upper portion of the first insulating pattern on the second area; forming organic light-emitting layers on the first electrodes; and forming a plurality of second electrodes on the organic light-emitting layers.

Description:
This application is a Continuation-In-Part Application of PCT International Application No. PCT/KR2004/002366 filed on Sep. 16, 2004, which designated the United States. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an organic electroluminescence display and a fabricating method thereof; and, more particularly, to an organic electroluminescence display and a fabricating method thereof enabling to simplify a manufacturing process and reduce a product cost by separating devices with a single insulating pattern. 
     BACKGROUND OF THE INVENTION 
     Generally, an organic electroluminescence display, which is one of flat plate displays, is configured in a way that an organic electroluminescence layer is inserted between a cathode layer and an anode layer on a transparent substrate. The organic electroluminescence display has a very thin thickness and, further, can be formed in a matrix type. Further, the organic electroluminescence display can be driven by a low voltage below 15 V, and has more excellent characteristics in a brightness, a viewing angle, a response time, a power consumption, or the like in comparison with TFT-LCD. Especially, the organic electroluminescence display has a fast response time of 1 μs in comparison with other displays and, accordingly, is very suitable for a next generation multimedia display to which a function of moving pictures is essential. 
     Since, however, an organic light-emitting layer and a cathode layer of the organic electroluminescence display are vulnerable to oxygen and moisture, an exposure to outer air should be excluded during a fabricating process in order to secure a reliability of the organic electroluminescence display. Hence, the fabricating process of the organic electroluminescence display is unable in general to use a photolithography for a pixellation or a patterning process. 
     The pixellation of the organic layer and the cathode layer of the organic electroluminescence display uses a direct pixellation using a shadow mask instead of the photolithography including a masking process and an etching process in which the organic layer and the cathode layer are exposed to oxygen and moisture. However, such a method is inadaptable to use if a pitch between pixels, i.e., an interval between lines constituting the organic layer and the cathode layer, is reduced to realize a high resolution. 
     One of the general methods of patterning the organic electroluminescence display is carried out in a manner that an insulating layer of an electrically insulating material and a separator are formed on an anode layer and a substrate and, then, a cathode layer is patterned by using the separator. 
     In this method, the insulating layer is formed on an entire area of the anode layer except a dot-shaped opening. In this case, the insulating layer defines pixels by the opening and inhibits a leakage current from edges of the cathodes. Further, the insulating layer prevents the cathode layer from being short-circuited with the anode layer at a boundary since the stacked organic layer becomes thinner near the separator due to a shadow effect by the separator in a direction perpendicular to the anode layer formed for patterning of the cathode layer. 
     Furthermore, the insulating layer should not have an overhang structure in order to prevent a cathode layer that will be formed later from being cut. Therefore, the insulating layer is generally formed of a positive photoresist material so as to have a positive profile. 
     The separator formed on the insulating layer crosses with the anode layer to be arranged so as to separate by a predetermined distance from each other as well as has the overhang structure so as not to make the cathode layer be short-circuited with an adjacent component. Especially, unlike a general patterning process, a negative profile should be constantly maintained in the separator in order to prevent the short circuit between adjacent cathode layer lines. If the separator is lost, there occurs a short-circuit between adjacent pixels. A negative photoresist material is used for the separator having the overhang structure. 
     In order to fabricate the organic electroluminescence display stably, both of the insulating layer and the separator are necessary. Yet, the photolithographic process is required for each process for fabricating the insulating layer and the separator, so that a fabricating process of the organic electroluminescence display becomes complicated and a product cost thereof increases. 
     Hereinafter, a fabricating method of a first conventional organic electroluminescence display will be described with reference to the accompanying drawings. 
       FIG. 1  is a plan view of the first conventional organic electroluminescence display. 
     As illustrated in  FIG. 1 , a plurality of first electrodes  12  that have a specific width and are formed of indium tin oxide (ITO) or the like are arranged on a transparent substrate  11  in a stripe type. An insulating pattern  13  of lattice type is stacked on the transparent substrate  11  having the first electrodes  12  in an area between the adjacent first electrodes  12  and an area crossing with the first electrodes  12 . Moreover, separators  14  are formed in an area of the insulating pattern  13  crossing with the first electrodes  12 . 
     Furthermore, organic light-emitting layers and second electrodes (not shown) are formed on the first electrodes  12  including the insulating pattern  13  and the separators  14 . 
     Referring to  FIGS. 2A to 2C  and  3 A to  3 C, the fabricating method of the first conventional organic electroluminescence display will be described in detail as follows. 
       FIGS. 2A to 2C  provide cross-sectional views illustrating a process of the fabricating method of the first conventional organic electroluminescence display, which are taken along the line A-A in  FIG. 1 . 
       FIGS. 3A to 3C  depict cross-sectional views illustrating the process of the fabricating method of the first conventional organic electroluminescence display, which are taken along the line B-B in  FIG. 1 . 
     As shown in  FIGS. 2A and 3A , an anode layer (not shown) made of indium tin oxide (ITO) or the like is stacked with a predetermined thickness on the transparent substrate  11  by a sputtering. A photoresist (not shown) is coated on the entirely deposited anode layer. The photoresist is exposed with a mask and developed, thereby forming a stripe type photoresist pattern (not shown). The anode layer is etched by using the photoresist pattern as a mask and a remaining photoresist is removed, thereby forming the stripe type first electrodes  12 . 
     As illustrated in  FIGS. 2B and 3B , an electrically insulating layer (not shown) is stacked on the transparent substrate  11  including the first electrodes  12 . The insulating layer can be formed of an organic or an inorganic material. As for the organic material, an acrylic-, a novolak-, an epoxy- and a polyimide-based photoresist or the like is used. As the inorganic material, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or the like is used. Next, by patterning the insulating layer, the lattice type insulating pattern  13  except the dot-shaped openings formed on the first electrodes  12  is formed on the first electrodes  12  and the transparent substrate  11  in an area between the adjacent first electrodes  12  and an area crossing with the first electrodes  12  at regular intervals. 
     As depicted in  FIGS. 2C and 3C , an organic photoresist of negative type (not shown) as an electrically insulating material is stacked on the insulating pattern  13 , and then a patterning process is carried out, thereby forming the separators  14  having a negative profile. In this case, the separators  14  cross with the first electrodes  12  and are arranged at regular intervals on the insulating pattern  13  between the dot-shaped openings. Further, the separators  14  have the overhang structure so as to prevent second electrodes  16  from being short-circuited with adjacent components. Thereafter, organic light-emitting layers  15  and the second electrodes  16  are stacked in order on an entire surface including the first electrodes  12  by using a shadow mask (not shown). In this connection, if the organic light-emitting layers  15  are stacked on the first electrode  12 , a thickness of the organic light-emitting layers  15  become thinner near the separators due to the shadow effect by the separators, so that the second electrodes  16  stacked on the organic light-emitting layers  15  can be short-circuited at a boundary with the first electrodes  12 . The insulating pattern  13  serves to prevent such short circuit. 
     Next, an encapsulation plate formed of a metal, a glass, or the like or a passivation layer formed of an organic or an inorganic thin film is formed on an entire surface including the second electrodes  16  in order to airtightly protect the organic light-emitting layers  15  and the second electrodes  16  vulnerable to moisture and oxygen from an outside. 
     In the aforementioned first conventional organic electroluminescence display and the fabricating method thereof, the photolithographic process needs to be carried out twice in order to form the insulating pattern and the separators, which results in a complex fabricating process and a high cost of materials. In addition, since the two layers of the insulating pattern and the separators are formed by respective patterning processes, an adhesion therebetween becomes poor. 
       FIG. 4  depicts a plan view of a second conventional organic electroluminescence display.  FIGS. 5A ,  5 B and  5 C present cross-sectional views illustrating the second conventional organic electroluminescence display, which are taken along the lines A-A′, B-B′ and C-C′ in  FIG. 4 , respectively. 
     As shown in  FIGS. 4 and 5A  to  5 C, a plurality of first electrodes  42  that have a specific width and are formed of indium tin oxide (ITO) or the like are arranged on a transparent substrate  41  in a stripe type. A lattice type insulating pattern  43  is stacked on the transparent substrate  41  having the first electrodes  42  in an area between the adjacent first electrodes  42  and an area crossing with the first electrodes  42 . Moreover, formed on the first electrodes  42  are openings  45  for exposing an area where pixels are formed. Therefore, the insulating pattern  43  in which the openings  45  where pixels are formed is exposed has a lattice shape. 
     Further, an insulating pattern  43   a  stacked in a direction in parallel with the plurality of first electrodes  42  is formed by using a half tone exposure mask having a rectangular-, a slit- and a chevron-shaped half tone pattern. An insulating pattern  43   b  formed in a direction crossing with the first electrodes  42  is formed in a normal tone pattern. At this time, the insulating pattern  43   a  has a thickness thinner than that of the insulating pattern  43   b . This is for excluding a possibility of an open circuit occurring since a thickness of the second electrodes formed in a direction crossing with the first electrodes  42  becomes thinner when the second electrodes (not shown) are deposited at a boundary between edges of the photoresist and the first electrodes  42 . 
     Hereinafter, a fabricating method of the second conventional organic electroluminescence display illustrated in  FIG. 4  will be described in detail with reference to  FIGS. 6A to 6D  and  7 A to  7 D. 
       FIGS. 6A to 6D  represent cross-sectional views showing a process of the fabricating method of the second conventional organic electroluminescence display, which is taken along the line A-A′ in  FIG. 4 .  FIGS. 7A to 7D  offer cross-sectional views illustrating the process of the fabricating method of the second conventional organic electroluminescence display, which is taken along the line B-B′ in  FIG. 4 . 
     As shown in  FIGS. 6A and 7A , the transparent substrate  41  that has been cleaned is prepared. In the present invention, a transparent glass substrate is used for the transparent substrate  41 . An anode layer (not shown) composed of indium tin oxide (ITO) or the like is entirely deposited on the transparent substrate  41  with a uniform thickness, and a photoresist (not illustrated in the drawing) is coated thereon. Then, an exposure and a development are carried out, thereby forming a photoresist pattern. The anode layer is etched by using such photoresist pattern as a mask and the photo-resist layer is removed, thereby forming the stripe type first electrodes  42 . 
     As depicted in  FIGS. 6B and 7B , an insulating layer forming process is carried out to inhibit a leakage current from the edges of the first electrodes  42  and to use, as a device separating layer, a photoresist (not shown) for an insulation between the first electrodes and the second electrode  48  that will be formed later. 
     In order to do so, a photoresist is coated on the transparent substrate  41 , and the insulating pattern  43  is formed by using an exposure mask (not illustrated in the drawing). At this time, the insulating pattern  43   a  stacked in a direction in parallel with the first electrode  42  is formed by using the half tone exposure mask of a rectangular-, a slit- and a chevron-shaped half tone pattern. Further, the insulating pattern  43   a  formed in the half tone pattern is formed with a thickness thinner than that of the insulating pattern  43   b  stacked in the direction crossing with the second electrodes. The thickness of the insulating pattern  43   a  formed in the half tone pattern is determined by controlling an opening ratio of the half tone area described in the exposure mask. 
     The reason for reducing the thickness of the insulating pattern  43   a  is to exclude a possibility of the open circuit occurring since a film thickness of the plurality of the second electrodes  48  running on the openings  45  where organic light-emitting layers  47  are formed and crossing with the first electrodes  42  becomes thinner at a boundary between edges of the insulating pattern  43   a  and the first electrodes  42  when the second electrodes  48  are evaporated. 
     Thereafter, as shown in  FIGS. 6C and 7C , the transparent substrate  41  is transferred inside a vacuum deposition apparatus. Then, the organic light-emitting layers  47  are formed on the first electrodes  42  through the openings of a first shadow mask  49  by using the insulating pattern  43   b  as a support of the first shadow mask  49 . If the insulating pattern  43   b  is used as the support, it is possible to adhere closely to the first shadow mask  49  without causing any damage on the first electrodes  42 , thereby enabling to prevent a lateral diffusion of the organic light-emitting layers  47 . 
     In this case, the organic light-emitting layers  47  are formed of a fluorescent and a phosphorescent organic luminescent material with low molecular weight such as Alq 3 , Anthracene, Ir(ppy) 3 , or the like. 
     Next, as illustrated in  FIGS. 6D and 7D , the second electrodes  48  are formed on the organic light-emitting layers  47  by using the insulating pattern  43   b  as a support of a second shadow mask  50  having a stripe type electrode pattern. If the insulating pattern  43   b  is used as the support, it is possible to adhere closely to the second shadow mask  50  without causing any damage on the organic light-emitting layers  47 , thereby enabling to prevent a lateral diffusion of the second electrodes  48 . 
     The second electrodes  48  mainly use a metal having an excellent electric conductivity such as Al, Li/Al, MgAg, Ca, or the like, and are stacked by a sputtering, an e-beam deposition, a thermal evaporation, or the like. And, an encapsulation layer made of a metal, a glass, or the like or a passivation layer formed of an organic or an inorganic material is formed on an entire surface including the second electrodes  48  so as to airtightly protect the organic light-emitting layers  47  vulnerable to moisture and oxygen from the outside. 
     In the aforementioned second conventional organic electroluminescence display and the fabricating method thereof, a single photolithographic process is carried out to form the insulating layer and the separators by using the half tone mask, so that the fabricating process becomes simple. Since the insulating layer and the separator are formed as a single layer, there is no problem of an adhesive strength therebetween. Further, since an alignment margin required for forming two separate layers of the insulating pattern and the separator is not needed, it is possible to increase an opening ratio of the organic electroluminescence display and a yield thereof. 
     However, there exist drawbacks in that it is difficult to design the half tone mask and, further, a product cost thereof increases in comparison with a conventional mask by about 1.5 times or more. Further, since there no overhang structure of the separators, a shadow mask is required for a patterning of the second electrodes. However, no shadow mask adaptable to a mass production of the organic electroluminescence display has been suggested. 
       FIG. 8  is a plan view of a third conventional organic electroluminescence display. 
     The third conventional organic electroluminescence display is formed by a method for forming a device separating layer of an electrically insulating property composed of an area having a thin thickness and a positive profile and an area having a negative profile and serving as a separator by employing an image reversal process using a half tone mask and an image reversal photoresist. 
     In general, in case of a positive photoresist, an exposed area is removed by a developer, and an area shielded by a mask pattern is formed as a pattern, wherein the pattern has a property of a positive profile. Meanwhile, in case of a negative photoresist, an exposed area is formed as a pattern that is insoluble in the developer by a cross-linking, wherein the pattern has a property of a negative profile. 
     However, in order that a single layer of insulating pattern serves as a general insulating layer and a separator as well, it should be made to have a positive profile in an area acting as the insulating layer and a negative profile in an area acting as the separator. To do so, a pattern having the positive profile needs to be formed in the single layer of the insulating pattern in advance. Then, by carrying out an image reversal, a flood exposure and a development thereto, the layer of the insulating pattern should be patterned to form the negative profile. Herein, the image reversal is carried out by an image reversal process using an image reversal photoresist or a general positive photosensitive material. Next, the image-reversed insulating pattern undergoes the flood exposure and the development so as to be patterned to form the negative profile. 
     In case of the typical image reversal using the image reversal photoresist, an initially formed photoresist has characteristics that a non-exposed portion does not dissolve and an exposed portion is developed, as in case of using the general positive photosensitive material. However, once the exposed portion of the photoresist is heated at a temperature over 115° C., the exposed portion becomes insoluble and, thus, the exposed portion is not developed by the developer. Herein, the change in the property of the exposed photoresist, i.e., from being soluble to being insoluble, by a heating is referred to as an image reversal and, further, the heating process for the image reversal is referred to as an image reversal baking. In the meantime, since the shield area still has a property of the positive photosensitive material, it does not dissolve in the developer. If the flood exposure is carried out on the photoresist, a portion having the changed property of being insoluble in the developer by the image reversal baking after the exposure has the same property even after the flood exposure. On the other hand, a portion shielded during the exposure has the property of the positive photosensitive material and, thus, is developed after the flood exposure. Accordingly, if the image reversal photoresist is used, the property of the positive photosensitive material is maintained at the beginning. However, after carrying out the exposure, the image reversal baking and the flood exposure, the exposed portion remains and the negative profile can be obtained, as same as the negative photosensitive material. 
     The image reversal method other than the method using the image reversal photoresist includes a method using an organic solvent instead of an aqueous developer and a method involving: coating and exposing a general positive photoresist; diffusing an image reversal base catalyst into the photoresist; carrying out an image reversal on the photoresist by performing the image reversal baking; and developing an unexposed area by carrying out the flood exposure. 
     A third conventional organic electroluminescence display employing the image reversal process using the image reversal photoresist will be described with reference to  FIGS. 9A to 9C . 
       FIGS. 9A ,  9 B and  9 C provide cross-sectional views of the third conventional organic electroluminescence display, which are taken along the lines A-A′, B-B′ and C-C′ in  FIG. 8 , respectively. 
     A plurality of first electrodes  62  that have a specific width and are formed of indium tin oxide (ITO) or the like are arranged on a transparent substrate  61  in a stripe type. A lattice type insulating pattern  63  is stacked on the transparent substrate  61  including the first electrodes  62  in an area between the adjacent first electrodes  62  and an area crossing with the first electrodes  62 . Moreover, formed on the first electrodes  62  are openings  65  for exposing an area where pixels are formed. Therefore, the insulating pattern  63  in which the openings  45  where the pixels are formed is exposed has a lattice shape. 
     An insulating pattern  63   a  stacked in parallel with the first electrodes  62  is formed by using a half tone exposure mask having a rectangular-, a slit- or a chevron-shaped half tone pattern. Further, an insulating pattern  63   b  stacked in a direction crossing with the first electrodes  62  is formed in a normal tone pattern. The insulating pattern  63   a  formed in the half tone pattern is formed with a thickness thinner than that of the insulating pattern  63   b  stacked in a direction crossing with the first electrodes. The thickness of the insulating pattern  63   a  is determined by controlling an opening ratio of the half tone area described in the exposure mask. 
     Trenches  66  are formed at a central portion of the insulating pattern  63   b  stacked in a direction crossing with the first electrodes  62 . Herein, an area having the trenches thereon is formed in a manner that the insulating pattern  63   b  undergoes an exposure using a stripe type mask, an image reversal by a heating, a flood exposure and a development. A certain portion of the photoresist remains inside such area thus formed, thereby forming the trenches  66  of the negative profile having the overhang structure. 
     The trenches  66  have a function of preventing a short circuit between the second electrodes adjacent to each other. Herein, organic light-emitting layers and the second electrodes (cathode layers) (not shown) are formed on the transparent substrate  61  including the openings  65 . 
     Referring to  FIGS. 10A to 10C  and  11 A to  11 C, the third conventional organic electroluminescence display illustrated in  FIG. 8  will be described in detail. 
       FIGS. 10A to 10C  present cross-sectional views illustrating a process of a fabricating method of the third conventional organic electroluminescence display, which are taken along the line A-A′ in  FIG. 8 . 
       FIGS. 11A to 11C  represent cross-sectional views illustrating the process of the fabricating method of the third conventional organic electroluminescence display, which are taken along the line B-B′ in  FIG. 8 . 
     As can be seen from  FIGS. 10A and 11A , an anode layer formed of indium tin oxide (ITO) or the like is stacked on the transparent substrate  61 , and a photoresist (not shown) is coated thereon. Then, an exposure and a development to the photoresist are carried out, thereby forming a stripe type photoresist pattern. Thereafter, the anode layer is etched by using such photoresist pattern as a mask and the photoresist pattern is removed, to thereby form the stripe type first electrodes  62 . 
     As can be seen from  FIGS. 10B and 11B , an insulating layer forming process is carried out inhibit a leakage current from edges of the first electrodes  62  and use, as a device separation structure layer, a photoresist (not shown) having an electrically insulating characteristic to prevent an electrical connection between the first electrodes  62  and the second electrodes  68  that will be formed later. 
     The image-reversed photoresist is coated on the transparent substrate  61  having the first electrodes  62  formed thereon. After coating the photoresist on the transparent substrate  61 , a prebaking is carried out at 100° C. for about 60 seconds so as to dry the photoresist. And, the insulating pattern  63  is formed by using a first exposure mask. The insulating pattern  63   a  stacked in parallel with the first electrodes  62  is formed in a half tone pattern by using an exposure mask having a rectangular-, a slit- or a chevron-shaped half tone pattern. The insulating pattern  63   a  is formed with a thickness thinner than that of the insulating pattern  63   b  crossing with the first electrodes  62 . The thickness of the half tone insulating pattern  63   a  is determined by controlling an opening ratio of a half tone area described in the exposure mask. 
     The reason for lowering the insulating pattern  63   a  in a direction in parallel with the first electrodes  61  than the insulating pattern  63   b  in a direction crossing with the first electrodes  62  is to exclude a possibility of the open circuit occurring since a thickness of the second electrode  68  becomes thinner when the second electrode  68  is deposited at a boundary between edges of the insulating pattern  63   a  and the first electrodes  62 . 
     As depicted in  FIGS. 10C and 11C , after the completion of the development, a dry process such as an air knife or a spin dry is carried out on the transparent substrate  61  at a temperature lower than 100° C. And, a second exposure process is carried out by using a second exposure mask for use in a device separating layer. After the completion of the second exposure process, a reversal baking is carried out for about 120 seconds at 120° C. A flood exposure is then carried out so as to change the property of the photoresist. Since the reversal baking for an image reversal and then the flood exposure are carried out, the property of the photoresist is changed in a manner that an exposed portion remains but a non-exposed portion is developed. In the second exposure process, the trenches are formed at a central portion of the normal tone insulating pattern  63   b  stacked in a direction perpendicular to the first electrodes  62  by carrying out an exposure with a width narrower than that of the insulating pattern  63   b.    
     The trenches  66  for an isolation of adjacent pixels are formed at the central portion of the normal tone insulating pattern  63   b  stacked in a direction perpendicular to the first electrodes  62  by a development process, wherein the trenches have a negative profile of an overhang structure. When the trenches  66  for the isolation of the adjacent pixels are formed, a depth of the trenches  66  is preferably greater than a sum of a deposition thickness of the organic light-emitting layers  67  and the second electrodes  68  that will be deposited later in order to exclude a possibility of a short circuit with the adjacent pixels. Specifically, the depth of the trenches  66  is preferably greater than the sum of the thickness of the organic light-emitting layers  67  and the second electrodes  68  by 1.5 to 5 times. 
     Subsequently, the transparent substrate  61  is subject to a post baking process and is transferred to a vacuum deposition apparatus. The organic light-emitting layers  67  are formed on the transparent substrate  61 . 
     Next, the second electrodes  68  are formed on the transparent substrate  61  including the organic light-emitting layers  67 . The second electrodes  68  mainly use a metal having an excellent electric conductivity such as Al, Li/Al, MgAg, Ca, or the like, and are stacked by a sputtering, an e-beam deposition, a thermal evaporation, or the like. And, an encapsulation layer made of a metal, a glass, or the like or a passivation layer made of an organic or an inorganic material is formed on an entire surface including the second electrodes  68  so as to make the organic light-emitting layers  67  vulnerable to moisture and oxygen airtight from the outside. 
     Moreover, a certain amount of the photoresist should remain at a bottom of the trenches  66  to prevent a short circuit between the first electrodes  62  and the metal of the second electrodes  68  deposited inside the trenches  66 . Therefore, a thickness of the photoresist remaining inside the trenches  66  is controlled by controlling a flood exposure amount or a development time. In this case, the remaining thickness of the photoresist is preferably about 1 μm. 
     In the aforementioned third conventional organic electroluminescence display and the fabricating method thereof, a single process is carried out to form the insulating layer and the separators by using the half tone mask and the image-reversal photoresist, and the trenches are formed at the central portion of the separators, thereby simplifying the fabricating process. Further, since an adhesive strength problem between the insulating pattern and the separators and an alignment margin problem are not occurred, an opening ratio of the organic electroluminescence display can increase. However, it is difficult to design the half tone mask and, further, a product cost thereof increases in comparison with a conventional mask by about 1.5 times or more. 
     Such fabricating methods of the conventional organic electroluminescence display have following drawbacks. 
     In the first conventional organic electroluminescence display and the fabricating method thereof, the photolithographic process is carried out twice to form the insulating pattern and the separators. Therefore, the alignment margin needs to be guaranteed, which results in a decrease in the opening ratio. Further, the adhesive strength between the insulating layer and the separators becomes poor, and the fabricating process becomes complex, thereby increasing the product cost. 
     In the second and the third conventional organic electroluminescence display and the fabricating method thereof, a single process is carried out to form the insulating pattern and the separators by using the half tone mask. However, in this case, it is difficult to design the half tone mask, and a product cost thereof increases in comparison with a conventional mask by 1.5 times or more. Besides, in case of the second conventional organic electroluminescence display, since there is no overhang structure of the separators, a shadow mask having a stripe type pattern is required for a patterning of the second electrode. However, such shadow mask is not adaptable to currently mass-produced organic electroluminescence displays. 
     SUMMARY OF THE INVENTION 
     It is, therefore, an object of the present invention to provide an organic electroluminescence display and a fabricating method thereof enabling to achieve an easy fabricating process using a general mask without requiring a special mask design technique; and a simple fabricating process and a reduced product cost by separating devices with a single insulating pattern. 
     In accordance with one aspect of the invention, there is provided a method of fabricating an organic electroluminescence display includes the steps of: (a) forming a plurality of stripe type first electrodes on a substrate; (b) forming an insulating layer on the substrate including the first electrodes; (c) forming a lattice type first insulating pattern in a first area crossing with the first electrodes and a second area between the first electrodes by patterning the insulating layer; (d) carrying out an image reversal on the first insulating pattern on the first area; (e) etching an upper portion of the first insulating pattern on the second area to form a second insulating pattern; (f) forming a plurality of organic light-emitting layers on the first electrodes; and (g) forming a plurality of second electrodes on the organic light-emitting layers. 
     In accordance with another aspect of the invention, there is provided a method of fabricating an organic electroluminescence display includes the steps of: (a) forming a plurality of stripe type first electrodes on a substrate; (b) forming an insulating layer on the substrate including the first electrodes; (c) forming a lattice type first insulating pattern in a first area crossing with the first electrodes and a second area between the first electrodes by patterning the insulating layer; (d) exposing the first insulating pattern on the first area by using an exposure mask having a light-transmitting area whose width is narrower than that of the first insulating pattern on the first area; (e) carrying out an image reversal by performing a heat treatment on the exposed first insulating pattern on the first area; (f) forming an exposed photoresist at an upper portion of the first insulating pattern on the second area and an upper portion of both sides of the first insulating pattern on the first area by carrying out a flood exposure; (g) forming a second insulating pattern having a negative profile in a way that the exposed insulating layer is removed by a developing process; (h) forming a plurality of organic light-emitting layers on the first electrodes; and (i) forming a plurality of second electrodes on the organic light-emitting layers. 
     In accordance with further another aspect of the invention, there is provided a method of fabricating an organic electroluminescence display includes the steps of: (a) forming a plurality of stripe type first electrodes on a substrate; (b) forming an insulating layer on the substrate including the first electrodes; (c) forming a lattice type first insulating pattern in a first area crossing with the first electrodes and a second area between the first electrodes by patterning the insulating layer; (d) exposing the first insulating pattern while aligning one side of a light-transmitting area of an exposure mask with an inner portion of the first, insulating pattern on the first area and the other side of the light-transmitting area with an outer portion of the first insulating pattern on the first area; (e) carrying out an image reversal by performing a heat treatment on the exposed first insulating pattern on the first area; (f) forming an exposed photoresist at an upper portion of the first insulating pattern on the second area and an upper portion of one side of the first insulating pattern on the first area by carrying out a flood exposure; (g) forming a second insulating pattern in a way that the exposed insulating layer is removed by a developing process; (h) forming a plurality of organic light-emitting layers on the first electrodes; and (i) forming a plurality of second electrodes on the organic light-emitting layers. 
     In accordance with still further another aspect of the invention, there is provided a method of fabricating an organic electroluminescence display includes the steps of: (a) forming a plurality of stripe type first electrodes on a substrate; (b) forming an insulating layer on the substrate including the first electrodes; (c) forming a lattice type first insulating pattern in a first area crossing with the first electrodes and a second area between the first electrodes by patterning the insulating layer; (d) exposing the first insulating pattern on the first area; (e) diffusing an image reversal base catalyst containing an amine group into the first insulating pattern; (f) carrying out an image reversal on the exposed first insulating pattern on the first area by performing a baking process; (g) forming an exposed photoresist at an upper portion of the first insulating pattern on the second area and an upper portion of both sides of the first insulating pattern on the first area by carrying out a flood exposure; (h) forming a second insulating pattern in a way that the exposed insulating layer is removed by a developing process; (i) forming a plurality of organic light-emitting layers on the first electrodes; and (j) forming a plurality of second electrodes on the organic light-emitting layers. 
     In accordance with yet further another aspect of the invention, there is provided a method of fabricating an organic electroluminescence display includes the steps of: (a) forming a plurality of stripe type first electrodes on a substrate; (b) forming an insulating layer on the substrate including the first electrodes; (c) forming a lattice type first insulating pattern in a first area crossing with the first electrodes and a second area between the first electrodes by patterning the insulating layer; (d) exposing the first insulating pattern on the first area by using an exposure mask having a shield area for shielding a portion corresponding to a central portion of the first insulating pattern on the first area and a light-transmitting area at a portion corresponding to a peripheral portion thereof; and (e) carrying out an image reversal by performing a heat treatment on the peripheral portion of the exposed first insulating pattern on the first area; (f) forming an exposed photoresist at an upper portion of the first insulating pattern on the second area and an upper central portion and an upper portion of both sides of the first insulating pattern on the first area by carrying out a flood exposure; (g) forming a second insulating pattern in a way that the exposed insulating layer is removed by a developing process; (h) forming a plurality of organic light-emitting layers on the first electrodes; and (i) forming a plurality of second electrodes on the organic light-emitting layers. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects and features of the present invention will become apparent from the following description of the preferred embodiments given in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a plan view of a conventional organic electroluminescence display; 
         FIGS. 2A to 2C  show cross-sectional views illustrating a process of a fabricating method of a first conventional organic electroluminescence display, which are taken along the line A-A′ in  FIG. 1 ; 
         FIGS. 3A to 3C  depict cross-sectional views illustrating the process of the fabricating method of the first conventional organic electroluminescence display, which are taken along the line B-B′ in  FIG. 1 ; 
         FIG. 4  describes a plan view of a second conventional organic electroluminescence display; 
         FIGS. 5A ,  5 B and  5 C provide cross-sectional views of the second conventional organic electroluminescence display, which are taken along the lines A-A′, B-B′ and C-C′ in  FIG. 4 , respectively; 
         FIGS. 6A to 6D  illustrate cross-sectional views illustrating a process of a fabricating method of the second conventional organic electroluminescence display, which are taken along the line A-A′ in  FIG. 4 ; 
         FIGS. 7A to 7D  present cross-sectional views illustrating the process of the fabricating method of the second conventional organic electroluminescence display, which are taken along the line B-B′ in  FIG. 4 ; 
         FIG. 8  represents a plan view of a third conventional organic electroluminescence display; 
         FIGS. 9A ,  9 B and  9 C depict cross-sectional views of the third conventional organic electroluminescence display, which are taken along the lines A-A′, B-B′ and C-C′ in  FIG. 8 , respectively; 
         FIGS. 10A to 10C  offer cross-sectional views illustrating a process of a fabricating method of the third conventional organic electroluminescence display, which are taken along the line A-A′ in  FIG. 8 ; 
         FIGS. 11A to 11C  sets forth cross-sectional views illustrating the process of the fabricating method of the third conventional organic electroluminescence display, which are taken along the line B-B′ in  FIG. 8 ; 
         FIG. 12  illustrates a plan view of an organic electroluminescence display in accordance with a first, a second, and a third preferred embodiment of the present invention; 
         FIGS. 13A and 13B  show plan views of an exposure mask used in a fabricating method of the organic electroluminescence display in accordance with the first, the second, and the third preferred embodiment of the present invention; 
         FIGS. 14A to 14G  provide cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 12 ; 
         FIGS. 15A to 15G  present cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 12 ; 
         FIGS. 16A to 16G  represent cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 12 ; 
         FIG. 17  describes a cross-sectional view of a process in which an exposure amount is controlled in a second exposure process of the first preferred embodiment of the present invention; 
         FIGS. 18A to 18G  show cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the second preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 12 ; 
         FIGS. 19A to 19G  illustrate cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the second preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 12 ; 
         FIGS. 20A to 20G  offer cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the second preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 12 ; 
         FIGS. 21A to 21H  provide cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the third preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 12 ; 
         FIGS. 22A to 22H  present cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the third preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 12 ; 
         FIGS. 23A to 23H  represent cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the third preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 12 ; 
         FIG. 24  demonstrates a plan view of an organic electroluminescence display in accordance with a fourth preferred embodiment of the present invention; 
         FIGS. 25A and 25B  depict plan views of an exposure mask used in a fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention; 
         FIGS. 26A to 26G  provide cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 24 ; 
         FIGS. 27A to 27G  present cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 24 ; and 
         FIGS. 28A to 28G  represent cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 24 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an organic electroluminescence display in accordance with a first, a second and a third preferred embodiment of the present invention and a fabricating method thereof will be described in detail with reference to the accompanying drawings. 
       FIG. 12  illustrates a plan view of an organic electroluminescence display in accordance with a first, a second, and a third preferred embodiment of the present invention. 
     A plurality of first electrodes  62  that have a specific width and are made of indium tin oxide (ITO), indium-doped zinc oxide (IZO or IXO), or the like are arranged on a transparent substrate  210  in a stripe type. A lattice type of insulating pattern  231  is stacked on the first electrodes  220  and the transparent substrate  210  in an area between the adjacent first electrodes  220  and an area crossing with the first electrodes  220 . Moreover, formed on the first electrodes  220  are openings  250  for exposing an area where pixels are formed. 
     Further, an insulating pattern  231  stacked in a direction in parallel with the first electrodes  220  is formed with a thickness thinner than that of an insulating pattern  231  in a direction perpendicular to the first electrodes  220 . This is for excluding a possibility of a open circuit occurring since a film thickness of second electrodes (not shown) formed in a direction perpendicular to the first electrodes  220  becomes thinner when the second electrodes are deposited at a boundary between edges of the insulating pattern  231  and the first electrodes  220 . 
       FIGS. 13A and 13B  show plan views of an exposure mask used in a fabricating method of the organic electroluminescence display in accordance with the first, the second, and the third preferred embodiment of the present invention. 
       FIG. 13A  is a plan view of a first exposure mask  140 . In the first exposure mask  140 , a shield area  141  corresponds to the insulating pattern  231  between the first electrodes  210  in  FIG. 12  and the insulating pattern  231  in a direction perpendicular to the first electrodes  210 , and a light-transmitting area  142  corresponds to an opening  250  in  FIG. 12 . 
       FIG. 13B  illustrates a plan view of a second exposure mask  240 . In the second exposure mask  240 , a shield area  241  corresponds to the insulating pattern  231  in a direction perpendicular to the first electrodes  210  in  FIG. 12 , and a light-transmitting area  242  corresponds to an area between the insulating pattern  231  between the first electrodes  210  in  FIG. 12  and the insulating pattern  231  in a direction perpendicular to the first electrodes  210 . 
     The fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention will be described in detail with reference to  FIGS. 14A to 14G ,  15 A to  15 G and  16 A to  16 G. 
       FIGS. 14A to 14G  provide cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 12 . 
       FIGS. 15A to 15G  present cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 12 . 
       FIGS. 16A to 16G  represent cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the first preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 12 . 
     As illustrated in  FIGS. 14A ,  15 A and  16 A, a transparent substrate  210  that has been cleaned is prepared. Generally, the transparent substrate  210  is formed of a transparent glass, a plastic substrate, or the like. An anode layer is stacked 1000 Å to 3000 Å thick on the transparent substrate  210  by depositing indium tin oxide (ITO) or the like. A sheet resistance of the anode layer is made to be equal to or lower than 10 Ω/cm 2 . The anode layer is stacked on the cleaned transparent substrate  210  by a sputtering or the like. Successively, a photoresist (not shown) is coated on the anode layer, and an exposure and a development are carried out to form a stripe type photoresist pattern (not illustrated in the drawing). The anode layer is etched by using the photoresist pattern as a mask and the photoresist pattern is removed, to thereby form the first electrodes  220  of a horizontal stripe pattern. 
     Thereafter, as will be described below, a process for forming an insulating layer is carried out in order to inhibit a leakage current from the edges of the first electrodes  220 . Further, the insulating pattern having an electrically insulating characteristic is used to prevent an electrical connection of the first electrodes  220  to the second electrodes  280  that will be formed later. 
     The photoresist  231  having a characteristic of an image reversal is coated on the transparent substrate  210  having the first electrodes  220  formed thereon. AZ 5214E (Clariant) is used for the photoresist  231 . The photoresist  231  is formed to have 1 μm to 5 μm thickness and, preferably, 3 μm to 5 μm thickness. Such photoresist  231  basically has a property of a positive photosensitive material. Yet, once the heat is applied at a certain temperature, generally, from 115° C. to 125° C. for 90 to 120 seconds after the exposure, an exposed portion is image-reversed and then becomes insoluble in a developer. 
     As can be seen from  FIGS. 14B ,  15 B and  16 B, after the photoresist  231  is coated about 4 μm thick, a prebaking is carried out at 100° C. for about 60 seconds so as to dry the photoresist  231 . Then, an area between the first electrodes  220  and an area crossing with the first electrodes  220  are shielded by using the first exposure mask  140  in  FIG. 13A  and, then, the photoresist  231  is exposed over 330 mJ/cm 2  to 500 mJ/cm 2 , thereby carrying out a first exposure process. 
     The photoresist  231  is divided into a non-exposure photoresist  231   a  and a first exposure photoresist  231   b  by the first exposure process. The non-exposure photoresist  231   a  has a property of being insoluble in a base developer, and the first exposure photoresist  231   b  has a property of being removable by the base developer. 
     As depicted in  FIGS. 14C ,  15 C and  16 C, if the first exposure photoresist  231   b  is removed by the base developer, the non-exposure photoresist  231   a  remains in an area between the first electrodes  220  and an area crossing with the first electrodes  220 , thereby forming on the first electrodes  220  a lattice type of insulating pattern having the openings  250  for exposing an area where pixels are formed. In this case, the photoresist pattern has a positive profile. 
     As described in  FIGS. 14D ,  15 D and  16 D, a second exposure process is carried out to expose the non-exposure layer  231   a  crossing with the first electrodes  220  at about 13 to 35 mJ/cm 2  by using the second exposure mask in  FIG. 13B . In this case, a width of a light-transmitting area of the second exposure mask  240  is designed to be narrower than that of the non-exposure photoresist  231   a  in an area crossing with the first electrodes  220 . 
     After performing the second exposure process, the exposed portion is heated at 120° C. for about 120 seconds, thereby forming a second exposure photoresist  231   c . In the second exposure photoresist  231   a , an unexposed portion is generated at a side of the non-exposure photoresist  231   a  perpendicular to the first electrodes  220 . The image-reversed second exposure photoresist  231   c  has a property of being insoluble in a developer. Further, since only the non-exposure photoresist  231   a  in an area crossing with the first electrodes  220  is exposed, the exposed portion is not shown in  FIG. 16D  taken along the line C-C′ in  FIG. 12 . 
     As illustrated in  FIGS. 14E ,  15 E and  16 E, a third exposure process in which a flood exposure is carried out at about 140 mJ/cm 2  to 230 mJ/cm 2  without using a mask is performed. If the third exposure process is carried out, the property of the second image-reversed exposure photoresist  231   c  in an area perpendicular to the first electrodes  220 , which is insoluble in a developer, is maintained. However, the non-exposure photoresist  231   a  formed at the side of the second exposure photoresist  231   c  or the like is exposed, thereby forming a third exposure photoresist  231   d . Since a uniform thickness of an insulating layer in parallel with the first electrodes  220  needs to remain in the third exposure process, the uniform thickness of the insulating layer in parallel with the first electrodes  220  remains by controlling an exposure amount. Accordingly, a lower side portion of the insulating layer perpendicular to the first electrodes  220  still remains as the non-exposure photoresist  231   a  after the development. 
     As illustrated in  FIGS. 14F ,  15 F and  16 F, if the development process is carried out, the second exposure photoresist  231   c  and the non-exposure photoresist  231   a  do not dissolve in a developer, whereas only the third exposure photoresist  231   d  is removed. Therefore, as illustrated in  FIG. 14F , the photoresist pattern in an area crossing with the first electrodes has a negative profile after the third exposure photoresist  231   b  is developed, and the non-exposure photoresist remains thereunder. 
       FIG. 17  provides a cross-sectional view of a process in which an exposure amount is controlled in the second exposure process of the first preferred embodiment of the present invention. 
     As illustrated in  FIG. 17 , the insulating pattern in an area crossing with the first electrodes  220  has a T-shaped structure according to an exposure amount used in the second exposure process. 
     As shown in  FIGS. 14G ,  15 G and  16 G, after the development process has been completed, a dry process such as an air knife or a spin dry is carried out on the transparent substrate  210  at a temperature lower than 100° C. Then, the transparent substrate  210  undergoes a postbaking process and is then transferred to a vacuum deposition apparatus. In the vacuum deposition apparatus, the organic light-emitting layers  270  are stacked on the transparent substrate  210  including the photoresist pattern  231  in the vacuum deposition apparatus. In this case, the organic light-emitting layers  270  are formed of low molecular fluorescent and phosphorescent organic light-emitting materials such as Alq 3 , Anthracene, Ir(ppy) 3 , or the like and polymeric light-emitting materials such as PPV(polyphenylenevinylene), PT(polythiophene), or the like and their derivatives. The low molecular based organic material is patterned through the use of a thermal evaporation in which a shadow mask is installed inside a chamber. And, the polymer based organic material is patterned by a spin coating, a transcription, an ink jet printing, or the like. 
     In case of the low molecular materials, it is possible to form a hole injection layer and a hole transfer layer thereon before the organic light-emitting layers  270  are formed. Further, an electron transport layer and an electron injection layer can be formed on the organic light-emitting layers. When a hole injection electrode having a high work function is used, the hole injection layer is an organic thin film layer having properties of enabling to have massive holes injected therein as well as let the injected hole move therein. Even if being unable to have electrons injected therein, or if the injection is possible, the hole injection layer is the organic thin film layer having a property of being unable to have the electrons move therein. Moreover, when an electron injection electrode having a low work function is used, the electron transport layer is an organic thin film layer having properties of enabling to have massive electrons injected therein as well as let the injected electrons move therein. Even if being unable to have holes injected therein, the electron transfer layer is the organic thin film layer having a property of being unable to let the holes move therein. In case of the polymer based materials, the hole transfer layer is formed before the formation of the organic light-emitting layers  270 . 
     Next, the second electrodes  280  are formed on the transparent substrate  210  including the organic light-emitting layers  270 . The second electrodes  280  mainly use a metal having an excellent electric conductivity such as Al, Li/Al, MgAg, Ca, or the like, and are stacked by a sputtering, an e-beam deposition, a thermal evaporation, or the like. And, an encapsulation layer formed of a metal, a glass, or the like or a passivation layer made of an organic or an inorganic material is formed on the transparent substrate  210  including the second electrodes  280  so as to airtightly protect the organic light-emitting layers  270  vulnerable to moisture and oxygen from the outside. 
     Hereinafter, a fabricating method of an organic electroluminescence display in accordance with a second preferred embodiment of the present invention will be described in detail with reference to  FIGS. 18A to 18G ,  FIGS. 19A to 19G  and  FIGS. 20A to 20G . 
       FIGS. 18A to 18G  show cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the second preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 12 . 
       FIGS. 19A to 19G  illustrate cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the second preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 12 . 
       FIGS. 20A to 20G  offer cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the second preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 12 . 
     As shown in  FIGS. 18A ,  19 A and  20 A, a transparent substrate  410  that has been cleaned is prepared. The transparent substrate  410  generally includes a glass substrate. An anode layer is stacked on the transparent substrate  410  by a sputtering, and a photoresist (not shown) is applied thereon. Then, an exposure and a development to the photoresist are carried out, thereby forming a stripe type of photoresist pattern (not shown). The anode layer is etched by using the photoresist pattern as a mask, thereby forming stripe type first electrodes  420 . 
     A process for forming an insulating layer is carried out in order to inhibit a leakage current from the edges of the first electrodes  420 . Further, the insulating pattern having an electrically insulating characteristic is used to prevent an electrical connection of the first electrodes  420  to the second electrodes  480  that will be formed later. A photoresist  431  having a characteristic of an image reversal is coated on the transparent substrate  410  having the first electrodes  420  formed thereon. AZ 5214E (Clariant) is used for the photoresist  431 . The photoresist  431  is formed 1 μm to 5 μm thickness. Such photoresist  431  basically has a property of a positive photosensitive material. Yet, once the heat is applied to the photoresist at a certain temperature, generally, from 115° C. to 125° C. for 90 to 120 seconds, an exposed portion thereof is image-reversed and, thus, becomes insoluble in a developer. 
     As can be seen from  FIGS. 18B ,  19 B and  20 B, after the photoresist  431  is applied about 3 μm to 5 μm thick, a prebaking is carried out at 100° C. for about 60 seconds so as to dry the photoresist  431 . Then, an area between the first electrodes  420  and an area crossing with the first electrodes  420  are shielded by using the first exposure mask  140  in  FIG. 13A  and, then, the photoresist  431  is exposed over 330 mJ/cm 2  to 500 mJ/cm 2 , thereby carrying out a first exposure process. 
     The photoresist  431  is divided into a non-exposure photoresist  431   a  and a first exposure photoresist  431   b  by the first exposure process. The non-exposure photoresist  431   a  becomes insoluble in a base developer, as same as the photoresist  431 , and the first exposure photoresist  431   b  becomes removable by the base developer. 
     As depicted in  FIGS. 18C ,  19 C and  20 C, if the first exposure photoresist  431   b  is removed by the alkaline developer, the non-exposure photoresist  431   a  remains in an area between the first electrodes  420  and an area crossing with the first electrodes  420 , thereby forming on the first electrodes  420  a lattice type of photoresist pattern having the openings  450  for exposing an area where pixels are formed. In this case, the photoresist pattern has a positive profile. 
     As described in  FIGS. 18D ,  19 D and  20 D, a second exposure process is carried out to expose the non-exposure layer  431   a  crossing with the first electrodes  420  at about 13 to 35 mJ/cm 2  by using the second exposure mask  240  illustrated in  FIG. 13B . As can be seen from  19 D, one side of a shield pattern of the second exposure mask  240  is aligned with an inner portion of the non-exposure photoresist  431   a , and the other side of the shield pattern is aligned with an outer portion of the non-exposure photoresist  421   a.    
     After carrying out the second exposure process, the exposed portion is image-reversed by carrying out a heat treatment at 120° C. for about 120 seconds, thereby forming a second exposure photoresist  431   a . As described in  FIG. 19D , the second exposure photoresist  431   a  perpendicular to the first electrodes  420  includes an unexposed portion formed at one side of the non-exposure photoresist  431   a  aligned with the inner portion of the shield pattern of the second exposure mask  240 . The image-reversed second exposure photoresist  431   c  has a property of being insoluble in a developer. Further, since only the non-exposure photoresist  431   a  in an area crossing with the first electrodes  420  is exposed, the exposed portion is not shown in  FIG. 20D  taken along the line C-C′ in  FIG. 12 . 
     As illustrated in  FIGS. 18E ,  19 E and  20 E, a third exposure process in which a flood exposure is carried out at about 140 mJ/cm 2  to 230 mJ/cm 2  without using a mask is performed. If the third exposure process is carried out, the property of the image-reversed second exposure photoresist  431   c  in an area perpendicular to the first electrodes  420 , which is insoluble in a developer, is maintained. However, the non-exposure photoresist  431   a  formed at one side of the second exposure photoresist  431   c  is exposed, thereby forming a third exposure photoresist  431   d . And, the non-exposure photoresist  431   a  remains under the third exposure photoresist  431   d . The other side of the non-exposure photoresist  431   a  is completely exposed and image-reversed in the second exposure process, so that the third exposure photoresist  431   d  is not formed. 
     Since a predetermined thickness of an insulating layer in parallel with the first electrodes  420  needs to remain in the third exposure process, an exposure amount is controlled to achieve the predetermined thickness of the insulating layer in parallel with the first electrodes  420 . Thus, a lower side portion of the insulating layer perpendicular to the first electrodes  420  remains as the non-exposure photoresist  431   a  after the development. 
     As illustrated in  FIGS. 18F ,  19 F and  20 F, if the development process is carried out, the second exposure photoresist  431   c  and the non-exposure photoresist  431   a  do not dissolve in a base developer, whereas only the third exposure photoresist  431   d  is removed. As a result, as illustrated in  FIG. 18F , one side of the photoresist pattern in an area crossing with the first electrodes  420  forms a negative profile due to an etching of the third exposure photoresist  431   b , and the non-exposure photoresist  431   a  remains thereunder. 
     The photoresist pattern in parallel with the first electrodes  420 , on which the second electrodes  480  run, is shielded by the second exposure mask  240  in the second exposure process and, thus, the second exposure photoresist mask  431   c  is not formed as shown in  FIG. 21F . In the third exposure process, the third exposure photoresist  431   d  is formed and developed by controlling an exposure amount, thereby comparatively lowering a thickness of the photoresist pattern in parallel with the first electrodes  420  than that of the photoresist pattern crossing with the first electrodes  420 . 
     The reason for lowering the thickness of the photoresist pattern in parallel with the first electrodes  420 , on which the second electrodes  480  run, is to exclude a possibility of an open circuit occurring since a film thickness of the second electrodes  480  formed in a direction perpendicular to the first electrodes  420  becomes thinner when the second electrodes  480  are deposited at a boundary between edges of the photoresist pattern and the first electrodes  420 . In this case, the remaining thickness of the non-exposure photoresist  231   a  is about 0.5 to 2 μm. 
     As shown in  FIGS. 18G ,  19 G and  20 G, after the development process has been completed, a dry process such as an air knife or a spin dry is carried out on the transparent substrate  420  at a temperature lower than 100° C. Then, the transparent substrate  410  undergoes a postbaking process and is then transferred to a vacuum deposition apparatus, and the organic light-emitting layers  470  are stacked on the transparent substrate  410  including the photoresist pattern in the vacuum deposition apparatus. 
     Thereafter, the second electrodes  480  are formed on the transparent substrate  410  including the organic light-emitting layers  470 . The second electrodes  480  mainly use a metal having an excellent electric conductivity such as Al or the like, and are stacked by a vacuum deposition. And, an encapsulation layer (not shown) made of a metal, a glass, or the like is formed on an entire surface including the second electrodes  480  so as to make the organic light-emitting layers  470  vulnerable to moisture and oxygen airtight from the outside. 
     Hereinafter, a fabricating method of an organic electroluminescence display in accordance with a third preferred embodiment of the present invention will be described in detail with reference to  FIGS. 21A to 21H ,  FIGS. 22A to 22H  and  FIGS. 23A to 23H . 
       FIGS. 21A to 21H  provide cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the third preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 12 . 
       FIGS. 22A to 22H  present cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the third preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 12 . 
       FIGS. 23A to 23H  represent cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the third preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 12 . 
     As shown in  FIGS. 21A ,  22 A and  23 A, a transparent substrate  510  that has been cleaned is prepared. As for the transparent substrate  510 , a glass substrate is generally used. An anode layer is deposited on the cleaned transparent substrate  510  by a sputtering, and a photoresist (not shown) is coated thereon. Then, an exposure and a development to the photoresist are carried out, thereby forming a stripe type of photoresist pattern (not shown). The anode layer is etched by using the photoresist pattern as a mask, thereby forming the stripe type first electrodes  520 . 
     Thereafter, a process for forming an insulating layer is carried out in order to inhibit a leakage current from the edges of the first electrodes  520 . Further, the insulating pattern  531  having an electrically insulating characteristic is coated with a thickness of about 4 μm on the transparent substrate  510  having the first electrodes  520  formed thereon. The photoresist  531  is formed of a positive photosensitive material, and a thickness thereof is 1 μm to 5 μm and, preferably, 3 μm to 5 μm. 
     As can be seen from  FIGS. 21B ,  22 B and  23 B, after the photoresist  531  is applied thereon, a prebaking is carried out at 100° C. for about 60 seconds so as to dry the photoresist  531 . Then, a first exposure process is carried out to shield an area between the first electrodes  520  and an area crossing with the first electrodes  520  and, then, expose the photoresist  231  over 330 mJ/cm 2  to 500 mJ/cm 2 , using the first exposure mask  140  in  FIG. 13A . 
     The photoresist  531  is divided into a non-exposure photoresist  531   a  and a first exposure photoresist  531   b  by the first exposure process. The non-exposure photoresist  531   a  becomes insoluble in a base developer, as same as the photoresist  531 , and the first exposure photoresist  531   b  becomes removable by the base developer. 
     As depicted in  FIGS. 21C ,  22 C and  23 C, if the first exposure photoresist  531   b  is removed by the alkaline developer, the non-exposure photoresist  531   a  remains in an area between the first electrodes  520  and an area crossing with the first electrodes  520 , thereby forming on the first electrodes  520  the lattice type insulating pattern  531  having the openings  550  for exposing an area where pixels are formed. In this case, the photoresist pattern has a positive profile. 
     As described in  FIGS. 21D ,  22 D and  23 D, a second exposure process is carried out to expose the non-exposure photoresist  531   a  crossing with the first electrodes  520  by using the second exposure mask  240  in  FIG. 13B . In this case, a width of a light-transmitting area of the second exposure mask  240  is designed to be narrower than that of the non-exposure photoresist  531   a  in an area crossing with the first electrodes  520 . 
     As depicted in  FIGS. 21E ,  22 E and  23 E, after carrying out the second exposure process, an image reversal base catalyst including amine such as imidazole, monazoline, triethanolamine and ammonia is diffused into the photoresist pattern  531 . 
     After diffusing the image reversal base catalyst into the photoresist pattern  531 , a baking process is carried out at a temperature 85° C. to 90° C. for more than 45 to 120 minutes, in a state that the base exists, thereby forming the second exposure photoresist  531   c . In the second exposure process, as depicted in  FIG. 21D , an unexposed portion is formed at a side of the non-exposure photoresist  531   a  perpendicular to the first electrodes  520 . 
     The second exposure photoresist  531   c  has a negative property of being insoluble in a base developer. Further, since only the non-exposure photoresist  531   a  in an area crossing with the first electrodes  520  is exposed, the exposed portion is not shown in  FIG. 16D  taken along the line C-C′ in  FIG. 12 . 
     Next, as illustrated in  FIGS. 21F ,  22 F and  23 F, a third exposure process in which a flood exposure is carried out at about 140 mJ/cm 2  to 230 mJ/cm 2  without using a mask is performed. If the third exposure process is carried out, the second exposure photoresist  531   c  in an area perpendicular to the first electrodes  520 , which is image-reversed to have a property of being insoluble in a developer, is maintained. However, the non-exposure photoresist  531   a  formed at the side of the second exposure photoresist  531   c  or the like is exposed, thereby forming a third exposure photoresist  531   d . Since a uniform thickness of an insulating layer in parallel with the first electrodes  520  needs to remain in the third exposure process, an exposure amount is controlled to achieve the uniform thickness of the insulating layer in parallel with the first electrodes  520 . Thus, a lower side portion of the insulating layer perpendicular to the first electrodes  520  remains as the non-exposure photoresist  531   a  after the development. 
     As illustrated in  FIGS. 21G ,  22 G and  23 G, if the development process is carried out, the second exposure photoresist  531   c  and the non-exposure photoresist  531   a  do not dissolve in a base developer, whereas only the third exposure photoresist  531   d  is removed. As a result, as illustrated in  FIG. 21G , the photoresist pattern in an area crossing with the first electrodes  520  forms a negative profile due to an etching of the third exposure photoresist  531   b , and the non-exposure photoresist  531   a  remains thereunder. 
     The photoresist pattern in parallel with the first electrodes  520 , on which second electrodes  580  run, is shielded by the second exposure mask pattern in the second exposure process and, thus, the second exposure photoresist mask  531   c  is not formed as shown in  FIG. 23G . In the third exposure process, the third exposure photoresist  531   d  is formed and developed by controlling an exposure amount, thereby comparatively lowering a thickness of the photoresist pattern in parallel with the first electrodes  520  than that of the photoresist pattern crossing with the first electrodes  520 . 
     The reason for lowering the thickness of the photoresist pattern in parallel with the first electrodes  520 , on which the second electrodes  580  run, is to exclude a possibility of a short circuit occurring since a film thickness of the second electrodes  580  formed in a direction perpendicular to the first electrodes  520  becomes thinner when the second electrodes  580  are deposited at a boundary between edges of the photoresist pattern and the first electrodes  520 . In this case, the remaining thickness of the non-exposure photoresist  531   a  is about 0.5 to 2 μm. 
     As shown in  FIGS. 21H ,  22 H and  23 H, after the development process has been completed, a dry process such as an air knife or a spin dry is carried out on the transparent substrate  520  at a temperature lower than 100° C. Then, the transparent substrate  510  undergoes a postbaking process and is then transferred to a vacuum deposition apparatus, and the organic light-emitting layers  570  are stacked on the transparent substrate  510  including the photoresist pattern in the vacuum deposition apparatus. 
     Thereafter, the second electrodes  580  are formed on the transparent substrate  510  including the organic light-emitting layers  570 . The second electrodes  580  mainly use a metal having an excellent electric conductivity such as Al or the like, and are stacked by a vacuum deposition. And, an encapsulation plate (not shown) made of a metal, a glass, or the like is formed on an entire surface including the second electrodes  580  so as to make the organic light-emitting layers  570  vulnerable to moisture and oxygen airtight from the outside. 
     Hereinafter, a fabricating method of an organic electroluminescence display in accordance with a fourth preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. 
       FIG. 24  is a plan view of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention. 
     A plurality of first electrodes  620  that have a specific width and are made of indium tin oxide (ITO) or the like are arranged on a transparent substrate  610  in a stripe type. A lattice type insulating pattern  631  composed of a photoresist pattern is stacked on an area between the adjacent first electrodes  620  and an area crossing with the first electrodes  620 . Moreover, formed on the first electrodes  620  are openings  650  for exposing an area where pixels are formed. Therefore, the insulating pattern  631  in which the openings  650  where pixels are formed is exposed has a lattice shape. 
     Further, the insulating pattern  631  stacked in a direction in parallel with the first electrodes  620  is formed with a thickness thinner than that of the insulating pattern  631  stacked in a direction perpendicular to the first electrodes  620 . This is for excluding a possibility of an open circuit occurring since the film thickness of second electrodes (not shown) formed in a direction perpendicular to the first electrodes  620  becomes thinner when the second electrodes are deposited at a boundary between edges of the insulating pattern  631  and the first electrodes  620 . 
     Trenches  660  are formed on a central portion of the insulating pattern  631  stacked in a direction perpendicular to the first electrodes  620 . Such trenches  660  have a function of preventing a short circuit between the second electrodes adjacent to each other. Herein, an organic light-emitting layers and the second electrodes (cathode layers) (not shown) are formed on the transparent substrate  610  including the openings  650 . 
       FIGS. 25A and 25B  depict plan views of an exposure mask used in the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention. 
       FIG. 25A  shows a plan view of a first exposure mask  640 . In the first exposure mask  640 , a shield area  641  corresponds to the insulating pattern  631  between the first electrodes  610  in  FIG. 24  and the insulating pattern  630   b  in a direction perpendicular to the first electrodes  620 , and a light-transmitting area  642  corresponds to an opening  651  in  FIG. 24 . 
       FIG. 25B  illustrates a plan view of a second exposure mask  740 . In the second exposure mask  740 , a shield area  741  corresponds to an area between the insulating pattern  631  in a direction perpendicular to the first electrodes  620  in  FIG. 24 , and a light-transmitting area  742  corresponds to the insulating pattern  631  in a direction perpendicular to the first electrodes  620  in  FIG. 24 . Further, a slit  743  having a shielding function is located at a central portion of the light-transmitting area  742 . 
     Hereinafter, the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention will be described in detail with reference to  FIGS. 26A to 26G ,  FIGS. 27A to 27G  and  FIGS. 28A to 28G . 
       FIGS. 26A to 26G  provide cross-sectional views illustrating a process of the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention, which are taken along the line A-A′ in  FIG. 24 . 
       FIGS. 27A to 27G  present cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention, which are taken along the line B-B′ in  FIG. 24 . 
       FIGS. 28A to 28G  represent cross-sectional views illustrating the process of the fabricating method of the organic electroluminescence display in accordance with the fourth preferred embodiment of the present invention, which are taken along the line C-C′ in  FIG. 24 . 
     As shown in  FIGS. 26A ,  27 A and  28 A, the transparent substrate  610  that has been cleaned is prepared. As for the transparent substrate  610 , a glass substrate is generally used. An anode layer is deposited on the cleaned transparent substrate  610  by a sputtering, and a photoresist (not shown) is coated thereon. Then, an exposure and a development to the photoresist are carried out, thereby forming a stripe type photoresist pattern (not shown). The anode layer is etched by using the photoresist pattern as a mask, thereby forming the stripe type first electrodes  620 . 
     Thereafter, a process for forming an insulating layer is carried out in order to inhibit a leakage current from the edges of the first electrodes  620 . Further, the photoresist layer  631  having a property of an image reversal is coated on the transparent substrate  610  having the first electrodes  620  formed thereon. AZ 5214E (Clariant) is used for the photoresist  631 . The photoresist  631  is formed to have 1 μm to 5 μm thick and, preferably, 3 μm to 5 μm thick. Such photoresist  631  basically has a property of a positive photosensitive material. Yet, once the heat is applied to the photoresist at a certain temperature, generally, from 115° C. to 125° C. for 90 to 120 seconds after the exposure, the exposed portion thereof is image-reversed and, then, becomes insoluble in a developer. 
     As can be seen from  FIGS. 26B ,  27 B and  28 B, after the photoresist  631  having a thickness of about 4 μm is coated on the transparent substrate  610  having the first electrodes  620  formed thereon, a prebaking is carried out at 100° C. for about 60 seconds so as to dry the photoresist  631 . Then, a first exposure process is carried out to shield an area between the first electrodes  620  and an area crossing with the first electrodes  620  and, then, expose the photoresist  631  over 330 mJ/cm 2  to 500 mJ/cm 2 , by using the first exposure mask  640  in  FIG. 25A . 
     The photoresist  631  is divided into a non-exposure photoresist  631   a  and a first exposure photoresist  631   b  by the first exposure process. The non-exposure photoresist  631   a  becomes insoluble in an alkaline developer, as same as the photoresist  631 , and the first exposure photoresist  631   b  becomes removable by the alkaline developer. 
     Sequentially, as depicted in  FIGS. 26C ,  27 C and  28 C, if the first exposure photoresist  631   b  is removed by the alkaline developer, the non-exposure photoresist  631   a  remains in an area between the first electrodes  620  and an area crossing with the first electrodes  620 , thereby forming on the first electrodes  620  a lattice type photoresist pattern having the openings  650  for exposing an area where pixels are formed. In this case, the photoresist pattern has a positive profile. 
     As described in  FIGS. 26D ,  27 D and  28 D, a second exposure process is carried out to expose the non-exposure layer  631   a  crossing with the first electrodes  620  at about 13 to 35 mJ/cm 2  by using the second exposure mask  740  in  FIG. 25B . 
     In this case, in the second exposure mask  740 , a width of a light-transmitting area including the slit  743  having the shielding function is designed to be narrower than that of the non-exposure photoresist  631   a  in an area crossing with the first electrodes  620 . 
     In the second exposure mask  740 , a shield area corresponds to a central portion of the non-exposure photoresist  631   a  and the removed first exposure photoresist  631   b  by the development, and a peripheral portion of the non-exposure photoresist  631   a  in a direction perpendicular to the first electrodes  620  forms a light-transmitting area. If the second exposure process is carried out, the peripheral portion of the non-exposure photoresist  631   a  in a direction perpendicular to the first electrodes  620  is exposed, whereas the central portion thereof is not exposed. 
     After the second exposure process is carried out, if the exposed portion is image-reversed by carrying out a heat treatment at 120° C. for 120 seconds, the peripheral portion of the non-exposure photoresist  631   a  is formed as a second exposure photoresist  631   c , and a central portion and both sides thereof remain as the non-exposure photoresist  631   a.    
     The second exposure photoresist  631   c  has a negative property and a characteristic of being insoluble in an alkaline developer. Further, since only the non-exposure photoresist  631   a  in an area crossing with the first electrodes  620  is exposed, the exposed portion is not shown in  FIG. 28D  taken along the line C-C′ in  FIG. 24 . 
     As illustrated in  FIGS. 26E ,  27 E and  28 E, a third exposure process in which a flood exposure is carried out at about 140 mJ/cm 2  to 230 mJ/cm 2  without using a mask is performed. If the third exposure process is carried out, the second exposure photoresist  631   c  in an area perpendicular to the first electrodes  620 , which is image-reversed to have a property of being insoluble in a developer, is maintained. However, the non-exposure photoresist  631   a  formed at the side and the central portion of the second exposure photoresist  631   c  is exposed, thereby forming a third exposure photoresist  631   d . Since a predetermined thickness of an insulating layer in parallel with the first electrodes  620  needs to remain in the third exposure process, an exposure amount is controlled to achieve the predetermined thickness of the insulating layer in parallel with the first electrodes  620  remains by controlling. Thus, a lower side portion of the insulating layer perpendicular to the first electrodes  620  remains as the non-exposure photoresist  631   a  after the development. 
     As illustrated in  FIGS. 26F ,  27 F and  28 F, if the development process is carried out, the second exposure photoresist  631   c  and the non-exposure photoresist  631   a  do not dissolve in the base developer, whereas only the third exposure photoresist  631   d  is removed. Accordingly, as illustrated in  FIG. 27F , in a photoresist pattern in an area 0crossing with the first electrodes  620 , the trenches  660  are formed at a central portion of the photoresist pattern due to an etching of the third exposure photoresist  631   d ; a negative profile is formed at the central portion and a side portion thereof by a development of the third exposure photoresist  631   d ; and the non-exposure photoresist  631   a  remains at a lower portion thereof. 
     The photoresist pattern in parallel with the first electrodes  620 , on which the second electrodes  680  run, is shielded by the second exposure mask  740  in the second exposure process and, thus, the second exposure photoresist  631   c  is not formed as shown in  FIG. 29F . In the third exposure process, the third exposure photoresist  631   d  is formed and developed by controlling an exposure amount, thereby comparatively lowering a thickness of the photoresist pattern in parallel with the first electrodes  620  than that of the photoresist pattern crossing with the first electrodes  620 . 
     The reason for lowering the thickness of the photoresist pattern in parallel with the first electrodes  620 , on which the second electrodes  680  run, is to exclude a possibility of a open circuit occurring since a film thickness of the second electrodes  680  formed in a direction perpendicular to the first electrodes  620  becomes thinner when the second electrodes  680  are deposited at a boundary between edges of the photoresist pattern and the first electrodes  620 . In this case, the remaining thickness of the non-exposure photoresist  631   a  is about 0.5 to 2 μm. 
     As shown in  FIGS. 26G ,  27 G and  28 G, after the development process has been completed, a dry process such as an air knife or a spin dry is carried out on the transparent substrate  620  at a temperature lower than 100° C. Then, the transparent substrate  610  is subject to a postbaking process, and then is transferred to a vacuum deposition apparatus. The organic light-emitting layers  670  are stacked on the transparent substrate  610  including the photoresist pattern in the vacuum deposition apparatus. Thereafter, the second electrodes  680  are formed on the transparent substrate  610  including the organic light-emitting layers  670 . 
     The trenches  660  formed on the central portion of the photoresist pattern perpendicular to the first electrodes  620  have a function of preventing a possibility of a short circuit with adjacent pixels when the organic light-emitting layers  670  and the second electrodes  680  are being stacked. A depth of the trenches  660  is preferably greater than a sum of a deposition thickness of the organic light-emitting layers  670  and the second electrodes  680  that will be deposited later. Specifically, the depth of the trenches  660  is preferably greater than the sum of the thickness of the organic light-emitting layers  670  and the second electrodes  680  by 1.5 to 5 times. 
     The second electrodes  680  mainly use a metal having an excellent electric conductivity such as Al or the like, and are stacked by a vacuum deposition. And, an encapsulation plate (not shown) made of a metal, a glass, or the like is formed on an entire surface including the second electrodes  680  so as to make the organic light-emitting layers  670  vulnerable to moisture and oxygen airtight from the outside. 
     The followings are effects of the organic electroluminescence display in accordance with the present invention and the fabricating method thereof. 
     First, in a prior art, it is difficult to design a half tone mask that is necessary for a fabrication of an insulating film serving as an insulating layer and a separator as well and, further, a product cost increases due to a high cost of the half tone mask in comparison with that of a general mask by about 1.5 times or more. However, in the present invention, it is possible to easily fabricate as a single layer the insulating film serving as the insulating pattern and the separator by using the general mask without requiring an additional parameter manipulation. Accordingly, a fabrication process becomes simple, and a cost of materials is reduced. 
     Second, since the insulating pattern and the separators are formed as a single photoresist, there is no adhesion problem. Further, an alignment margin required for forming two layers of the insulating pattern and the separator is eliminated, thereby increasing an opening ratio and a yield and decreasing the product cost. 
     While the invention has been shown and described with respect to the preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.