Organic light emitting diode display device and method of fabricating the same

Abstract

An organic light emitting diode display device includes a first substrate including a display region, wherein a plurality of pixel regions are defined in the display region; a first electrode over the first substrate and in each of the plurality of pixel regions; a first bank on edges of the first electrode and including an insulating material blocking penetration of light; a second bank on the first bank and including an insulating material having a hydrophobic property; an organic light emitting layer on the first electrode and a portion of the first bank; and a second electrode on the organic light emitting layer and covering an entire surface of the display region.

What is claimed is: 
     
       1. An organic light emitting diode display device, comprising:
 a first substrate including a display region, wherein a plurality of pixel regions are defined in the display region; 
 a first electrode over the first substrate and in each of the plurality of pixel regions; 
 a first bank on edges of the first electrode and including an insulating material having a property for blocking penetration of light; 
 a second bank on the first bank and including an insulating material having a hydrophobic property; 
 an organic light emitting layer on the first electrode and a portion of the first bank surrounded by the second bank in each of the plurality of pixel regions, wherein the organic light emitting layer on the portion of the first bank directly contacts side surfaces of the second bank; and 
 a second electrode on the organic light emitting layer and covering an entire surface of the display region, 
 wherein the first bank and the second bank form a double-layered structure, and the insulating material of the first bank is different from the insulating material of the second bank. 
 
     
     
       2. The organic light emitting diode display device according to  claim 1 , wherein the insulating material included in the first bank is a light-absorption material. 
     
     
       3. The organic light emitting diode display device according to  claim 1 , wherein the first bank has a first width and the second bank has a second width smaller than the first width. 
     
     
       4. The organic light emitting diode display device according to  claim 1 , wherein the first bank includes chromium oxide CrOx, and the second bank includes at least one of polyimide containing fluorine, styrene, methylmethacrylate, and polytetrafluoroethylene. 
     
     
       5. The organic light emitting diode display device according to  claim 1 , further comprising:
 a switching thin film transistor and a driving thin film transistor in each of the plurality of pixel regions and under the first electrode; and 
 a passivation layer covering the switching thin film transistor and the driving thin film transistor and exposing a drain electrode of the driving thin film transistor, 
 wherein the first electrode is disposed on the passivation layer and contacts the drain electrode of the driving thin film transistor. 
 
     
     
       6. The organic light emitting diode display device according to  claim 5 , further comprising:
 a gate line and a data line connected to the switching thin film transistor and crossing each other to define each of the plurality of pixel regions; and 
 a power line connected to the driving thin film transistor and parallel to the gate line or the data line. 
 
     
     
       7. The organic light emitting diode display device according to  claim 6 , further comprising a second substrate facing the first substrate or an encapsulation film contacting the second electrode. 
     
     
       8. A method of fabricating an organic light emitting diode display device, comprising:
 forming a first electrode over a first substrate including a display region, which includes a plurality of pixel regions, the first electrode formed in each of the plurality of pixel regions; 
 forming a first bank on edges of the first electrode and including an insulating material blocking penetration of light; 
 forming a second bank on the first bank, the second bank including an insulating material having a hydrophobic property; 
 forming an organic light emitting layer on the first electrode and a portion of the first bank surrounded by the second bank in each of the plurality of pixel regions, wherein the organic light emitting layer on the portion of the first bank directly contacts side surfaces of the second bank; and 
 forming a second electrode on the organic light emitting layer, the second electrode covering an entire surface of the display region, 
 wherein the first bank and the second bank form a double-layered structure, and the insulating material of the first bank is different from the insulating material of the second bank. 
 
     
     
       9. The method according to  claim 8 , wherein the insulating material included in the first bank is a light-absorption material. 
     
     
       10. The method according to  claim 8 , wherein the first bank includes chromium oxide CrOx, and the second bank includes at least one of polyimide containing fluorine, styrene, methylmethacrylate, and polytetrafluoroethylene. 
     
     
       11. The method according to  claim 8 , wherein the first bank has a first width and the second bank has a second width smaller than the first width. 
     
     
       12. The method according to  claim 11 , wherein forming the second bank includes:
 forming an organic insulating material layer on the first bank by applying the insulating material having the hydrophobic property to an entire surface of the first substrate; 
 disposing an exposing mask including a light-transmitting region and a light-blocking region over the organic insulating material layer and irradiating UV light of 100 to 990 mW/cm 2  to the organic insulating material layer through the exposing mask; and 
 developing the organic insulating material layer, which has been exposed to the UV light, 
 wherein the light-transmitting region is disposed over an overlapping area of the first bank and the second bank such that the UV light is irradiated only to the overlapping area corresponding to the second width. 
 
     
     
       13. The method according to  claim 12 , wherein forming the organic light emitting layer includes:
 forming an organic light emitting material layer on the first electrode and the portion of the first bank in each of the plurality of pixel regions surrounded by the second bank by spraying or dropping a liquid phase organic light emitting material using an liquid-releasing apparatus or a nozzle-coating apparatus; and 
 curing the organic light emitting material layer to form the organic light emitting layer. 
 
     
     
       14. The method according to  claim 8 , further comprising:
 forming gate and data lines and a power line and forming a switching thin film transistor and a driving thin film transistor in each of the plurality of pixel regions before forming the first electrode, the gate and data lines crossing each other to define each of the plurality of pixel regions, the power line parallel to the gate line or the data line, the switching thin film transistor connected to the gate and data lines, and the driving thin film transistor connected to the power line and the switching thin film transistor; and 
 forming a passivation layer covering the switching thin film transistor and the driving thin film transistor and exposing a drain electrode of the driving thin film transistor, 
 wherein the first electrode is disposed on the passivation layer and contacts the drain electrode of the driving thin film transistor. 
 
     
     
       15. An organic light emitting diode display device comprising:
 a first substrate;   a plurality of gate lines and a plurality of data lines crossing each other to define a plurality of pixel regions in a display region;   a thin film transistor on the first substrate and in each of the plurality of pixel regions;   a first electrode having a first portion, second portion and third portion on the thin film transistor;   a bank disposed on the second and third portions of the first electrode, the bank having a double-layered structure and including a first bank and a second bank on the first bank;   an organic light emitting layer having a central region with a first height and an edge region with a second height on the first portion of the first electrode, the first height of the organic light emitting layer and the second height of the organic light emitting layer are different; and   a second electrode on the organic light emitting layer,   wherein the central region of the organic light emitting layer contacts with the first portion of the first electrode, and the edge region of the organic light emitting layer on a portion of the first bank directly contacts a side surface of the second bank, and   wherein the second bank includes an insulating material having a hydrophobic property, and the first bank includes a material different from the insulating material of the second bank.    
     
     
       16. The organic light emitting diode display device according to claim 15, wherein the first height of the organic light emitting layer is less than the second height of the organic light emitting layer.  
     
     
       17. The organic light emitting diode display device according to claim 15, wherein a transition from the first height of the organic light emitting layer to the second height of the organic light emitting layer is a curved slope.  
     
     
       18. The organic light emitting diode display device according to claim 15, wherein a transition from the first height of the organic light emitting layer to the second height of the organic light emitting layer is a linear slope.  
     
     
       19. The organic light emitting diode display device according to claim 15, wherein the second portion of the first electrode is adjacent to an edge of the data line, and the third portion of the first electrode is connected to the thin film transistor.  
     
     
       20. The organic light emitting diode display device according to claim 15, wherein the thin film transistor includes a switching thin film transistor connected to one of the plurality of gate lines and one of the plurality of data lines and a driving thin film transistor connected to the switching thin film transistor, and wherein the third portion of the first electrode is connected to the driving thin film transistor.  
     
     
       21. The organic light emitting diode display device according to claim 20, wherein each of the switching thin film transistor and the driving thin film transistor includes a gate electrode, a semiconductor layer, a source electrode and a drain electrode.  
     
     
       22. The organic light emitting diode display device according to claim 21, wherein the semiconductor layer includes one of oxide semiconductor, amorphous silicon, and polysilicon.  
     
     
       23. The organic light emitting diode display device according to claim 21, wherein each of the switching thin film transistor and the driving thin film transistor further includes an etch-stopper covering a center of the semiconductor layer, and wherein the source and drain electrodes are spaced apart from each other on the etch-stopper.  
     
     
       24. The organic light emitting diode display device according to claim 15, further comprising a passivation layer between the thin film transistor and the first electrode and having a drain contact hole, wherein the third portion of the first electrode contacts a drain electrode of the thin film transistor through the drain contact hole, and the bank covers the drain contact hole.  
     
     
       25. The organic light emitting diode display device according to claim 24, wherein the drain contact hole overlaps a semiconductor layer of the thin film transistor.  
     
     
       26. The organic light emitting diode display device according to claim 24, further comprising an interlayer insulating layer between a semiconductor layer and the drain electrode and having a semiconductor contact hole, wherein the drain electrode is connected to the semiconductor layer through the semiconductor contact hole, and the drain contact hole overlaps the semiconductor contact hole.  
     
     
       27. The organic light emitting diode display device according to claim 15, wherein the bank includes a light blocking material.  
     
     
       28. The organic light emitting diode display device according to claim 15, wherein the first bank has a first width and the second bank has a second width smaller than the first width.  
     
     
       29. The organic light emitting diode display device according to claim 15, wherein there is no residue of the bank material between the organic light emitting layer and the first portion of the first electrode.  
     
     
       30. The organic light emitting diode display device according to claim 15, further comprising a second substrate facing the first substrate or an encapsulation film contacting the second electrode.  
     
     
       31. An organic light emitting diode display device comprising:
 a first substrate;   a plurality of gate lines and a plurality of data lines crossing the plurality of gate lines in a display region;   a first electrode having a first portion, second portion and third portion;   a bank disposed on the second and third portions of the first electrode, the bank having a double-layered structure and including a first bank and a second bank on the first bank;   an organic light emitting layer having a central region with a first height and an edge region with a second height on the first portion of the first electrode, the first height of the organic light emitting layer and the second height of the organic light emitting layer are different; and   a second electrode on the organic light emitting layer,   wherein the central region of the organic light emitting layer contacts with the first portion of the first electrode, and the edge region of the organic light emitting layer on a portion of the first bank directly contacts a side surface of the second bank, and   wherein the second bank includes an insulating material having a hydrophobic property, and the first bank includes a material different from the insulating material of the second bank.    
     
     
       32. The organic light emitting diode display device according to claim 31, wherein the first height of the organic light emitting layer is less than the second height of the organic light emitting layer.  
     
     
       33. The organic light emitting diode display device according to claim 31, wherein a transition from the first height of the organic light emitting layer to the second height of the organic light emitting layer is a curved slope.  
     
     
       34. The organic light emitting diode display device according to claim 31, wherein a transition from the first height of the organic light emitting layer to the second height of the organic light emitting layer is a linear slope.