Organic light-emitting display device with spacer between sub-pixels

Abstract

Disclosed is an organic light-emitting display device, which prevents lateral current leakage by providing a structure on a bank so as to cut off an organic material, which is formed in a subsequent process, around the structure.

What is claimed is: 
     
       1. An organic light-emitting display device comprising:
 a substrate including a plurality of pixels, each pixel comprising a first sub-pixel, a second sub-pixel and a third sub-pixel, each of the first to third sub-pixels having an emission portion and a non-emission portion surrounding the emission portion; 
 a first electrode on the emission portion of each of the first to third sub-pixels; 
 a bank overlapping with an edge of the first electrode on the non-emission portion; 
 a first spacer having a negatively tapered shape and provided on the bank at least between the first sub-pixel and the second sub-pixel; 
 a second spacer placed between the second sub-pixel and the third sub-pixel, wherein the second spacer is higher in height than the first spacer; 
 an organic stack above the first electrode and the first spacer, wherein the organic stack on the first electrode is spaced apart from sides of the first electrode spacer; and 
 a second electrode disposed on the organic stack, 
 wherein a length of the first spacer in a first direction is shorter than a dimension of the first sub-pixel in the first direction, the second sub-pixel and the third sub-pixel separated from the first sub-pixel in a second direction crossing the first direction, and 
 wherein the first spacer is placed to block the emission portion of the second sub-pixel from the emission portion of the first sub-pixel, and 
 wherein the organic stack includes at least two stacks, and a charge generation layer between the at least two stacks. 
 
     
     
       2. The device according to  claim 1 , wherein the length of the first spacer in the first direction is greater than a dimension of the emission portion of the second sub-pixel in the first direction. 
     
     
       3. The device according to  claim 1 , wherein the second sub-pixel and the third sub-pixel are alternately disposed in the first direction, and wherein the first spacer extends between the first sub-pixel and the third sub-pixel. 
     
     
       4. The device according to  claim 3 , wherein the first sub-pixel extends in the first direction at least to an edge of the third sub-pixel, the edge located at a side of the third pixel away from the second sub-pixel. 
     
     
       5. The device according to  claim 1 , wherein the first spacer comprises a first segment between the first sub-pixel and the second sub-pixel and a second segment between the second sub-pixel and the third sub-pixel, and wherein the first segment and the second segment are directly connected. 
     
     
       6. The device according to  claim 5 , wherein the second segment is longer than a dimension of the second sub-pixel or a dimension of the third sub-pixels in the second direction. 
     
     
       7. The device according to  claim 1 , wherein the first spacer comprises a first segment between the first sub-pixel and the second sub-pixel, and a second segment between the first sub-pixel and the third sub-pixel, and the first segment and the second segment are separated in the first direction. 
     
     
       8. The device according to  claim 1 , wherein the first spacer has a width ranging from 1 μm to 5 μm in the second direction crossing the first direction. 
     
     
       9. The device according to  claim 1 , wherein a threshold voltage of the first sub-pixel is higher than a threshold voltage of the second sub-pixel. 
     
     
       10. The device according to  claim 1 , wherein the second sub-pixel and the third sub-pixel are smaller than the first sub-pixel. 
     
     
       11. The device according to  claim 1 , wherein the organic stack includes a hole injection layer contacting the first electrode and at least one stack, each of the at least one stack including a sequential stack of a hole transport layer, a light-emitting layer, and an electron transport layer. 
     
     
       12. The device according to  claim 11 , wherein the organic stack comprises a plurality of stacks, each of the stack including stacks includes a sequential stack of a hole transport layer, a light-emitting layer and an electron transport layer, the device further including a charge generation layer between the plurality of stacks. 
     
     
       13. The device according to  claim 11 , wherein at last least one layer of the organic stack has a gap at sides of the first spacer. 
     
     
       14. The device according to  claim 11 , wherein at least one layer of the organic stack on the first spacer has an island shape. 
     
     
       15. The device according to  claim 1 , wherein the first sub-pixel is a blue sub-pixel, the second sub-pixel is a red sub-pixel, and the third sub-pixel is a green sub-pixel. 
     
     
       16. An organic light emitting device, comprising:
 a first sub-pixel in a pixel configured to emit light of a first color, the first sub-pixel comprising two first electrodes and a first portion of an organic stack sandwiched between the two first electrodes; 
 a second sub-pixel adjacent to and spaced apart from the first sub-pixel in the pixel, the second sub-pixel configured to emit light of a second color, the second sub-pixel comprising two second electrodes and a second portion of the organic stack sandwiched between the two second electrodes; 
 a third sub-pixel configured to emit light of a third color, the third sub-pixel comprising two third electrodes and a third portion of the organic stack sandwiched between the two third electrodes, wherein the second sub-pixel and the third sub-pixel are alternately disposed in a first direction, adjacent to the first sub-pixel; 
 a bank overlapping with an edge of each bottom electrode of the first electrodes, the second electrodes and the third electrodes;  
 a first spacer between the first sub-pixel and the second sub-pixel, the first spacer placed to block the second portion of the organic stack of the second sub-pixel from the first portion of the organic stack of the first sub-pixel; and 
 a second spacer placed between the second sub-pixel and the third sub-pixel, wherein the second spacer is higher in height than the first spacer, 
 wherein a length of the first spacer in the first direction is shorter than a dimension of an emission portion of the first sub-pixel in the first direction, the second sub-pixel separated from the first sub-pixel in a second direction crossing the first direction, and 
 wherein the organic stack includes at least two stacks, and a charge generation layer between the at least two stacks over the first sub-pixel, second sub-pixel, and the third sub-pixel. 
 
     
     
       17. An organic light-emitting display device comprising:
 a substrate including a plurality of pixels, each pixel comprising a first sub-pixel, a second sub-pixel and a third sub-pixel, each of the first to third sub-pixels having an emission portion and a non-emission portion;   a first electrode on the emission portion of each of the first to third sub-pixels;   a bank overlapping with an edge of the first electrode on the non-emission portion;   a first spacer having a negatively tapered shape and provided on the bank;   a second spacer placed between the second sub-pixel and the third sub-pixel, wherein the second spacer is higher in height than the first spacer;   an organic stack above the first electrode and the first spacer, wherein the organic stack on the first electrode is spaced apart from sides of the first spacer; and   a second electrode disposed on the organic stack,   wherein the first spacer comprises a first segment and a second segment, the first segment between the first sub-pixel and the second sub-pixel,   wherein the first spacer is placed to block the emission portion of the second sub-pixel from the emission portion of the first sub-pixel, and   wherein the organic stack includes at least two stacks, and a charge generation layer between the at least two stacks.    
     
     
       18. The organic light-emitting display device according to claim 17, wherein the second segment is between the second sub-pixel and the third sub-pixel, and the first segment and the second segment are directly connected.  
     
     
       19. The organic light-emitting display device according to claim 17,
 wherein the first segment is disposed along a first direction, and   wherein the second sub-pixel and the third sub-pixel are alternately disposed in the first direction next to the first sub-pixel.    
     
     
       20. The organic light-emitting display device according to claim 17, wherein at least one end of the first segment is positioned next to the emission portion of the first sub-pixel.  
     
     
       21. The organic light-emitting display device according to claim 17, wherein the first segment includes a longitudinal pattern parallel to at least one side of the emission portion of the first sub-pixel.  
     
     
       22. The organic light-emitting display device according to claim 17, wherein a length of the first segment of the first spacer in a first direction is shorter than a length of the first sub-pixel in the first direction, and is longer than the emission portion of the second sub-pixel in the first direction.  
     
     
       23. The organic light-emitting display device according to claim 18, wherein the second spacer has a positively tapered shape on the bank.  
     
     
       24. The organic light-emitting display device according to claim 17, further comprising a capping layer on the second electrode.  
     
     
       25. The organic light-emitting display device according to claim 17, wherein a disconnected portion of the organic stack is positioned on an upper surface of the bank.  
     
     
       26. The organic light-emitting display device according to claim 17, wherein a slope of the first spacer is different from a slope of the bank.  
     
     
       27. The organic light-emitting display device according to claim 17, wherein a first color light-emitting layer at the first sub-pixel, a second color light-emitting layer at the second sub-pixel and a third color light-emitting layer at the third sub-pixel are provided in each stack of the at least two stacks.  
     
     
       28. The organic light-emitting display device according to claim 27, wherein a first thickness of the first color light emitting layer is thinnest and a second thickness of the second color emitting layer is thickest among the first color light emitting layer, the second light emitting layer and the third emitting layer.  
     
     
       29. The organic light-emitting display device according to claim 27, wherein the first, second and third color light-emitting layers have a same host and a same dopant at vertically different stacks, respectively, at the first sub-pixel, the second sub-pixel and the third sub-pixel.  
     
     
       30. The organic light-emitting display device according to claim 27,
 wherein the at least two stacks comprise a hole injection layer, and a hole transport layer under the first color light emitting layer, the second light emitting layer and the third emitting layer, and an electron transport layer on the first color light emitting layer, the second light emitting layer and the third emitting layer, and   the organic stack includes a hole injection layer, and the at least two stacks, and the charge generation layer is disposed between adjacent stacks.    
     
     
       31. The organic light-emitting display device according to claim 17, wherein the charge generation layer comprises a p-type charge generation layer and an n-type charge generation layer.  
     
     
       32. The organic light-emitting display device according to claim 24, wherein the capping layer has a disconnection portion at at least one side of the first spacer.