Abstract:
A method and an apparatus for fabricating an organic light emitting display, in which a large-sized transmissible film is fabricated to be easily used in an affixing process for a large-sized substrate. The apparatus includes: a first chamber including a plurality of first through holes and having a first transmissible film sealing the plurality of first through holes, the first chamber adapted to affix a first substrate having an Organic Light Emitting Diode (OLED) to a second substrate having a desiccant agent; and a second chamber having a second through hole in a predetermined region and having a second transmissible film sealing the second through hole, the second chamber adapted to harden a sealant interposed between the first and second substrates to seal the first substrate to the second substrates.

Description:
CLAIM OF PRIORITY  
       [0001]     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. § 119 from an application for FABRICA TING METHOD OF ORGANIC LIGHT EMITTING DISPLAY DEVICE AND FABRICATING APPARATUS OF THE SAME earlier filed in the Korean Intellectual Property Office on 20 Sep. 2005 and there duly assigned Serial No. 10-2005-0087424.  
       BACKGROUND OF THE INVENTION  
       [0002]     1 Field of the Invention  
         [0003]     The present invention relates to fabricating an organic light emitting display, and more particularly, to a method and an apparatus for fabricating an organic light emitting display including forming a first substrate with an Organic Light Emitting Diode (OLED) and a second substrate for sealing the first substrate. An affixing process and a sealing process of the first and second substrates are performed separately.  
         [0004]     2. Description of the Related Art  
         [0005]     Recently, OLED displays using OLEDs have attracted attention. An OLED display is provided with a plurality of pixels, each including an OLED formed on a glass substrate, and a Thin Film Transistor (TFT) to drive the OLED. Such an OLED is susceptible to water, so that a sealing structure has been proposed for waterproofing, in which a deposition substrate is covered with a metal cap coated with a desiccant agent or a sealing glass substrate. In this sealing structure, a sealing process is performed by applying a load of a flat plate to a device glass substrate formed with the OLED and the sealing glass substrate or applying a uniform pressure of N 2  to an entire surface thereof.  
         [0006]     A chamber for fabricating an organic light emitting display is used to perform both an affixing process for a first substrate and a second substrate and a hardening process for a sealant using ultraviolet (UV) light rays.  
         [0007]     First, the first substrate is vacuum-affixed to a metallic suction plate opposite to a transmissible film, and the second substrate is placed on the transmissible film. An OLED formed in a predetermined area of the first substrate is opposite to a desiccant agent layer formed in a predetermined area of the second substrate.  
         [0008]     Then, a transferring unit moves the suction plate down, and the transferring unit is pressed until the first substrate and the second substrate are spaced apart from each other by a predetermined gap, thereby applying a load to the suction plate or applying a uniform pressure of N 2  to an entire surface of the suction plate.  
         [0009]     Then, a UV emitter provided outside of the chamber emits UV light rays to a sealant through the transmissible film and the second substrate. The sealant is then hardened, so that the first substrate and the second substrate are affixed to each other.  
         [0010]     In the substrate sealing method described above, the transmissible film used in a process of hardening the sealant must endure the pressure of the affixing process and have a high UV transmissivity. Quartz, tempered glass, and hardened plastics satisfy these conditions and can be used as the transmissible film.  
         [0011]     However, when the organic light emitting display using a large-sized substrate is in the affixing process, it is difficult to fabricate a transmissible film which maintains rigidity to endure the pressure, thereby limiting the affixing process of the large-sized substrate.  
       SUMMARY OF THE INVENTION  
       [0012]     Accordingly, it is an aspect of the present invention to provide a method and an apparatus for fabricating an organic light emitting display, in which a chamber for performing an affixing process of a large-sized substrate and a chamber for performing a UV-hardening process are provided separately to facilitate processing a large-sized transmissible film.  
         [0013]     In an exemplary embodiment of the present invention, an apparatus for fabricating an organic light emitting display includes: a first chamber including a plurality of first through holes and having a first transmissible film sealing the plurality of first through holes, the first chamber adapted to affix a first substrate having an Organic Light Emitting Diode (OLED) to a second substrate having a desiccant agent; and a second chamber having a second through hole in a predetermined region and having a second transmissible film sealing the second through hole, the second chamber adapted to harden a sealant interposed between the first and second substrates to seal the first substrate to the second substrates.  
         [0014]     The apparatus preferably further includes a transferring unit adapted to transfer the first and second substrates affixed to each other from the first chamber to the second chamber.  
         [0015]     The first and second transmissible films each preferably include a film selected from a group consisting of quartz, tempered glass and hardened plastic.  
         [0016]     The plurality of first through holes are preferably arranged in an outer circumference on a bottom of the first chamber. The plurality of first through holes are preferably arranged in at least six outer points on the bottom of the first chamber. The plurality of first through holes are preferably shaped like circles having a diameter in a range of 5 mm˜30 mm. The plurality of first through holes are alternatively preferably shaped like rectangles having a size of at least 5 mm×30 mm.  
         [0017]     The second transmissible film is preferably divided into at least two parts together corresponding to a size of the first substrate.  
         [0018]     The second through hole is preferably arranged on either a top or a bottom of the second chamber.  
         [0019]     In another exemplary embodiment of the present invention, a method of fabricating an organic light emitting display includes: affixing a first substrate and a second substrate to each other in a first chamber having a plurality of first through holes and having a first transmissible film sealing the plurality of first through holes; exposing at least one region of the affixed first and second substrates to ultraviolet (UV) light rays; and applying a UV-hardening process to a sealant along a seal line of the first and second substrates in a second chamber having a second through hole in a predetermined region and having a second transmissible film sealing the second through hole.  
         [0020]     Affixing the first and second substrates preferably includes aligning the first substrate and the second substrate and pressing the first substrate toward the second substrate. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily apparent as the present invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:  
         [0022]      FIG. 1  is a view of an organic light emitting display;  
         [0023]      FIGS. 2A and 2B  are respective views of a first chamber and a second chamber for an organic light emitting display according to an embodiment of the present invention;  
         [0024]      FIG. 3A  is an exploded perspective view of a coupled substrate and the first chamber according to an embodiment of the present invention;  
         [0025]      FIG. 3B  is an exploded perspective view of the coupled substrate and the second chamber according to an embodiment of the present invention; and  
         [0026]      FIG. 4  is a flowchart of a method of fabricating the organic light emitting display according to an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF INVENTION  
       [0027]      FIG. 1  is a view of an organic light emitting display fabricated in a chamber.  
         [0028]     Referring to  FIG. 1 , a chamber (not shown) for fabricating the organic light emitting display is used to perform both an affixing process for a first substrate  10  and a second substrate  20  and a hardening process for a sealant using ultraviolet (UV) light rays.  
         [0029]     First, the first substrate  10  is vacuum-affixed to a metallic suction plate  40  opposite to a transmissible film  30 , and the second substrate  20  is placed on the transmissible film  30 . An OLED  11  formed in a predetermined area of the first substrate  10  is opposite to a desiccant agent layer  12  formed in a predetermined area of the second substrate  20 .  
         [0030]     Then, a transferring unit (not shown) moves the suction plate  40  down, and the transferring unit is pressed until the first substrate  10  and the second substrate  20  are spaced apart from each other by a predetermined gap, thereby applying a load to the suction plate  40  or applying a uniform pressure of N 2  to an entire surface of the suction plate  40 .  
         [0031]     Then, a UV emitter  50  provided outside of the chamber (not shown) emits UV light rays to a sealant  15  through the transmissible film  30  and the second substrate  20 . The sealant  15  is then hardened, so that the first substrate  10  and the second substrate  20  are affixed to each other.  
         [0032]     In the substrate sealing method described above, the transmissible film  30  used in a process of hardening the sealant  15  must endure the pressure of the affixing process and have a high UV transmissivity. Quartz, tempered glass, and hardened plastics satisfy these conditions and can be used as the transmissible film  30 .  
         [0033]     However, when the organic light emitting display using a large-sized substrate is in the affixing process, it is difficult to fabricate a transmissible film  30  which maintains rigidity to endure the pressure, thereby limiting the affixing process of the large-sized substrate.  
         [0034]     Hereinafter, exemplary embodiments of the present invention will be described with reference to accompanying drawings.  
         [0035]      FIGS. 2A and 2B  are respective views of a first chamber and a second chamber for an organic light emitting display according to an embodiment of the present invention.  
         [0036]     Referring to  FIGS.2A and 2B , an apparatus for an organic light emitting display according to an embodiment of the present invention performs a process of affixing a first substrate  120  and a second substrate  130  to each other in a first chamber  100 , and then transfers the affixed first and second substrates  120  and  130  to the second chamber  200  by a transferring unit (not shown). Thereafter, a UV-hardening process is performed to seal the first substrate  120  to the second substrate  130 .  
         [0037]     First, in the first chamber  100 , the first substrate  120  formed with an OLED (not shown) and the second substrate  130  used to seal the first substrate  120  are affixed to each other.  
         [0038]     That is, the first substrate  120  is vacuum-affixed to a metallic suction plate  121  opposite to a first transmissible film  111 , and the second substrate  130  is put on a mask  140 .  
         [0039]     The mask  140  is formed on a supporting plate  150  and used to prevent the UV light from having an effect on any region except a part corresponding to a sealant. The supporting plate  150  supports the first substrate  120 , the second substrate  130  and the mask  140  to perform the affixing process for the first substrate  120  and the second substrate  130 .  
         [0040]     Then, the transferring unit moves the suction plate  121  down, and the transferring unit is pressed until the first substrate  120  and the second substrate  130  are spaced apart from each other by a predetermined gap, thereby applying a load to the suction plate  121  or applying a uniform pressure of N 2  to an entire surface of the suction plate  121 .  
         [0041]     The first chamber  100  is formed with a plurality of first through holes  110  in an outer circumference on the bottom thereof, and each first through hole  110  is sealed with the first transmissible film  111 . At least six first through holes  110  are formed at outer points on the bottom of the first chamber  100 . The shape of the first through hole  110  can be a circle having a diameter of 5 mm-30 mm, or a rectangle having a size of at least 5 mm×30 mm. Furthermore, the supporting plate  150  is formed with through holes having a predetermined size at positions corresponding to the first through holes  110 , thereby allowing the UV light to pass through the supporting plate  150  and reach the sealant (not shown) between the first substrate  120  and the second substrate  130 .  
         [0042]     A UV emitter  112  is provided outside the first chamber  100 . The UV light is directed by the UV emitter  112  to the sealant (not shown) between the first and second substrates  120  and  130  via the first transmissible film  111  to seal the plurality of first through holes  110 .  
         [0043]     Then, in the second chamber  200  performing the next process, a UV-hardening process is applied to the sealant in a seal line through a mask  240  in order to effect the entire adhesion between the first substrate  120  and the second substrate  130 .  
         [0044]     Furthermore, the second chamber  200  is formed with a second through hole  210  at a predetermined region on the bottom thereof, and the second through hole  210  is sealed with a second transmissible film  211 . The second transmissible film  211  can be divided into at least two parts corresponding to the size of the first substrate  120 . That is, because it is difficult to provide the second transmissible film  211  having a size corresponding to a large-sized substrate so that the UV light impinges on the substrate, the large-sized substrate is divided into predetermined regions and the second transmissible film  211  is placed in each region.  
         [0045]     When a film growth surface of a circuit (not shown) formed on the coupled substrate is placed inside the seal line, the film growth surface of the circuit is not damaged even though the UV light impinges a top surface of the second chamber  200 , so that the second through hole  210  can be formed on the top surface of the second chamber  200 .  
         [0046]     Furthermore, a UV emitter  212  is placed outside the second chamber  200 . The UV emitter  212  directs the UV light to the sealant between the first and second substrates  120  and  130  via the second transmissible film  211  to sealing the plurality of second through holes  210 . In the second chamber  200 , the adhesion process between the first substrate  120  and the second substrate  130  is not performed, so that no pressure is applied to the second transmissible film  211 . Thus, the UV-hardening process is performed without pressing the second transmissible film  211 .  
         [0047]      FIG. 3A  is an exploded perspective view of a coupled substrate and the first chamber according to an embodiment of the present invention, and  FIG. 3B  is an exploded perspective view of the coupled substrate and the second chamber according to an embodiment of the present invention.  
         [0048]     Below, the first substrate  120  and the second substrate  130  affixed to each other are referred to as a “coupled substrate”. Furthermore, the accompanying drawings show the bottoms of the first chamber  100  and the second chamber  200 .  
         [0049]     Referring to  FIG. 3A and 3B , a plurality of spots  113  of the coupled substrate corresponding to the first through holes  110  of the first chamber  100  and the seal line are sealed with the sealant. When the coupled substrate is placed inside the first chamber  100 , only the spots  113  are exposed to the UV light, so that the sealant in the spots  113  is hardened, thereby preventing misalignment between the first substrate  120  and the second substrate  130  when the coupled substrate moves from the first chamber  100  to the second chamber  200 . As described above, when the UV-hardening process is applied to only the spots  113 , the transmissible film  111  need not have a large area or thickness, so that the first transmissible film  111  is formed in the first through hole  110  through which the UV passes. Therefore, even though a load due to the adhesion process is generated in the first chamber  100 , the first transmissible film  111  is not overstrained.  
         [0050]     The first transmissible film  111  and the second transmissible film  211  respectively formed in the first chamber  100  and the second chamber  200  are made of a material having a high transmissivity to the UV. For example, the material includes quartz, tempered glass, and hardened plastics.  
         [0051]      FIG. 4  is a flowchart of a method of fabricating the organic light emitting display according to an embodiment of the present invention.  
         [0052]     Referring to  FIG. 4 , the organic light emitting display according to an embodiment of the present invention is fabricated by a first step ST 100  through a third step ST 300 . In particular, the present invention relates to a fabricating method for an organic light emitting display that includes a first substrate formed with an OLED and a second substrate sealing the first substrate.  
         [0053]     In the first step ST 100 , the first substrate and the second substrate are affixed to each other in a first chamber formed with a plurality of first through holes on the bottom thereof, in which the first through holes are sealed with a first transmissible film.  
         [0054]     First, the first substrate is vacuum-affixed to a metallic suction plate opposite to the first transmissible film, and the second substrate is placed on the first transmissible film. The OLED formed in a predetermined region of the first substrate is arranged to face a desiccant agent layer formed in a predetermined region of the second substrate. Then, the transferring unit moves the suction plate down, and the transferring unit is suctioned until the first substrate and the second substrate are spaced apart from each other by a predetermined gap, thereby applying a load to the suction plate or applying a uniform pressure of N 2  to an entire surface of the suction plate.  
         [0055]     In a second step ST 200 , spots of the coupled first and second substrates are exposed to UV light. That is, only the spots on the coupled substrate corresponding to the plurality of first through holes are exposed to UV light, thereby hardening a sealant of the spot, thereby preventing the misalignment between the first and second substrates when transferring the coupled first and second substrates from the first chamber to the second chamber in order to perform the following third step ST 300 .  
         [0056]     In the third step ST 300 , a UV-hardening process is applied to the sealant along the seal line of the first and second substrates in the second chamber formed with second through holes in a predetermined region on the bottom thereof and having a second transmissible film sealing up the second through holes. Furthermore, the adhesion process between the first and second substrates is not performed in the second chamber, so that the second transmissible film is not pressed. Therefore, the UV-hardening process is performed without pressing the second transmissible film.  
         [0057]     As described above, the adhesion process and the UV-hardening process according to an embodiment of the present invention are separately performed in different chambers as compared with the conventional technology in which the adhesion process and the UV-hardening process are performed in one chamber. Therefore, the transmissible film for UV-transmission need not receive pressure due to the adhesion process. Accordingly, the transmissible film becomes thin, thereby facilitating the process of the transmissible film.  
         [0058]     Although exemplary embodiments of the present invention have been shown and described, it is understood that modifications can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims.