Flexible display device and method for manufacturing the same

Abstract

Discussed is a flexible display device to reduce a width of a bezel. The flexible display device includes a substrate being formed of a flexible material, a plurality of gate lines and a plurality of data lines crossing each other, a plurality of pads formed in a pad area of a non-display area, a plurality of links formed in a link area of the non-display area a plurality of insulation films formed over the entire surface of the substrate, and a first bending hole formed in a bending area of the non-display area, the first bending hole passing through at least one of the insulation films disposed under the link, wherein the bending area is bent such that the pads are disposed on the lower surface of the substrate.

What is claimed is: 
     
       1. A method for manufacturing a flexible display device comprising:
 forming a substrate defined by a display area and a non-display area being an outer region of the display area and including a link area and a pad area, using a flexible material;   forming a buffer film over the surface of the substrate;   forming a gate insulation film over the surface of the buffer film;   forming gate lines in the display area on the gate insulation film;   forming an interlayer insulation film over the entire surface of the gate insulation film such that the interlayer insulation film covers the gate lines;   forming a first bending hole passing through at least the gate insulation film and the interlayer insulation film in a bending area, wherein the bending area bends such that the pad area of the non-display area is disposed on the lower surface of the substrate;   forming data lines and a plurality of links, wherein the data lines are formed in the display area on the interlayer insulation film such that the data lines cross the gate lines, and wherein the plurality of links are connected to signal lines selected from the gate lines and the data lines in the linking area on the interlayer insulation film;   forming a protective film over the surface of the interlayer insulation film such that the protective film covers the data lines and the links;   forming a plurality of pads connected to the links and connected to an exterior circuit to supply a driving signal to the signal line on the protective film; and   bending the bending area such that the pads are disposed on the back side of the surface of the substrate.   
     
     
       2. The method according to  claim 1 , further comprising: forming an anti-etching layer in at least a part including the bending area of the non-display area on the substrate, before formation of the buffer film,
 wherein the first bending hole further passes through the buffer film to expose at least a part of the anti-etching layer, during formation of the first bending hole, and   the link directly contacts at least a part of the anti-etching layer exposed through the first bending hole in the bending area, during formation of the link.   
     
     
       3. The method according to  claim 2 , further comprising forming at least one second bending hole passing through the protective film and the anti-etching layer in the periphery of the link in the first bending hole to expose a part of the substrate, after formation of the protective film. 
     
     
       4. The method according to  claim 2 , wherein the anti-etching layer is further formed in the pad area during formation of the anti-etching layer, and
 the first bending hole is further formed in the pad area during formation of the first bending hole.   
     
     
       5. The method according to  claim 2 , wherein, during formation of the anti-etching layer, the anti-etching layer is formed using a material having softness higher than the insulation films and having an etch ratio lower than the insulation films upon etching to form the first bending hole. 
     
     
       6. The method according to  claim 2 , wherein, during formation of the anti-etching layer, the anti-etching layer is formed using at least one of ITO, Mo, Ti, Cu, Ag, Au and a-Si. 
     
     
       7. The method according to  claim 2 , wherein the anti-etching layer includes a plurality of anti-etching patterns corresponding to the links, during formation of the anti-etching layer, and
 the first bending hole includes a plurality of first bending holes to expose at least a part of the respective anti-etching patterns during formation of the first bending hole, and   The links contact the anti-etching patterns exposed through the first bending holes, respectively, during formation of the data lines and the links.   
     
     
       8. The method according to  claim 1 , further comprising:
 forming an anti-etching layer in the bending area of the non-display area on the substrate, before formation of the buffer film; and   forming a pre-bending hole passing through the buffer film in the bending area such that the pre-bending hole exposes at least a part of the anti-etching layer, after formation of the buffer film.   wherein the first bending hole passes through the gate insulation film and the interlayer insulation film in the pre-bending hole, in a width smaller than the pre-bending the hole to expose the anti-etching layer, during formation of the first bending hole, and   the link directly contacts at least a part of the anti-etching layer exposed through the pre-bending hole and the first bending hole in the bending area, during formation of the link.   
     
     
       9. A display device comprising:
 a flexible substrate including a display area, a pad area, and a bending area between the display area and the pad area;   a plurality of insulation films including a buffer film, a gate insulation layer and an interlayer insulation film, which are sequentially formed on the flexible substrate, at least one first hole passing through at least one of the buffer film, the gate insulation film and the interlayer insulation film in the bending area;   a plurality of link lines crossing the bending area on the interlayer insulating film, each of the link lines including a portion disposed above the at least one first hole in the bending area, wherein at least a portion of the at least one first hole is provided between two adjacent link lines in the bending area;   a plurality of gate lines and a plurality of data lines formed on the flexible substrate;   a plurality of thin film transistors formed at intersections between the gate lines and the data lines; and   a plurality of pads formed in the pad area, each pad electrically connected with one of the gate or data lines.    
     
     
       10. The display device according to claim 9, wherein the link lines are formed in a link area of the flexible substrate,
 wherein the link lines connect the respective pads to the gate and data lines on the flexible substrate, and   wherein the bending area and the link area overlap with each other.    
     
     
       11. The display device according to claim 10, wherein the bending area is wider than the link area.  
     
     
       12. The display device according to claim 10, wherein the link area is wider than the bending area.  
     
     
       13. The display device according to claim 9. wherein the link lines are disposed in the bending area and in a link area of the flexible substrate.  
     
     
       14. The display device according to claim 9, further comprising:
 at least one second hole formed within the at least one first hole,   the at least one second hole being located at a periphery area of one of the link lines, and passing through a part of one of the insulation films.    
     
     
       15. The display device according to claim 14, wherein the at least one second hole exposes an upper surface of the flexible substrate in the bending area.  
     
     
       16. The display device according to claim 14, further comprising:
 a protective film covering the link lines,   wherein the at least one second hole passes through the protective film.    
     
     
       17. The display device according to claim 16, further comprising:
 an active layer formed in a part of a pixel area on the buffer film;   a gate electrode formed on the gate insulation layer,   source and drain electrodes on the interlayer insulation film;   a first electrode on the protective film;   a light emitting layer on the first electrode; and   a second electrode on the light emitting layer.    
     
     
       18. The display device according to claim 17, further comprising:
 a sealing layer on the second electrode in the display area.    
     
     
       19. The display device according to claim 17, further comprising:
 a bank formed on a periphery of the pixel area on the protective film to overlap at least a part of an edge of the first electrode.    
     
     
       20. The display device according to claim 14, wherein for a pixel area in the display area, a corresponding gate line is formed on a gate insulation layer together with a gate electrode, and a corresponding link line is connected to the corresponding gate line through a link hole which passes through an interlayer insulation film to expose at least a part of the corresponding gate line.  
     
     
       21. The display device according to claim 20, further comprising:
 a pad connected to the corresponding link line through a pad hole.    
     
     
       22. The display device according to claim 21, wherein the at least one first hole or the at least one second hole is disposed between the link hole and the pad hole.  
     
     
       23. The display device according to claim 22 wherein a length of one of the link lines is longer than a distance between the link hole and the pad hole.  
     
     
       24. The display device according to claim 9, further comprising:
 an anti-etching layer formed between the flexible substrate and the insulation films in the bending area,   wherein a part of the anti-etching layer is exposed by the at least one first hole, and   wherein one of the link lines contacts the exposed part of the anti-etching layer in the bending area.    
     
     
       25. The display device according to claim 14, further comprising:
 an anti-etching layer formed between the flexible substrate and the insulation films in the bending area,   wherein a part of the anti-etching layer is exposed by the at least one first hole,   wherein one of the link lines contacts the exposed part of the anti-etching layer in the bending area, and   wherein the at least one second hole passes through the anti-etching layer.    
     
     
       26. The display device according to claim 9, wherein a width of each of the at least one first hole is wider than a width of each of the link lines.  
     
     
       27. The display device according to claim 9, further comprising:
 a protective film formed on the flexible substrate,   wherein the protective film fills the at least one first hole in the bending area.    
     
     
       28. The display device according to claim 9, wherein the bending area is bent such that the pad area including the pads is provided under the display area of the flexible substrate.