Method for fabricating display device and display device

Patent metadata

Field	Value
Publication number	US-9614015-B2
Application number	US-201514704002-A
Country	US
Kind code	B2
Filing date	May 5, 2015
Priority date	Dec 2, 2014
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A method for fabricating a display device includes forming a thin film transistor on a base substrate, forming a first electrode connected to the thin film transistor, forming a pixel defining layer overlapping a portion of the first electrode, such that the pixel defining layer exposes a portion of the first electrode and partitions pixel areas, forming a block copolymer layer on the first electrode and the pixel defining layer, patterning the block copolymer layer, etching the pixel defining layer by using the patterned block copolymer layer as a mask, such that an uneven pixel defining layer with a plurality of defining layer grooves is formed, and forming a light emitting layer on the first electrode and the uneven pixel defining layer.

First claim

What is claimed is:

1. A method for fabricating a display device, the method comprising:
forming a thin film transistor on a base substrate;
forming a first electrode connected to the thin film transistor;
forming a pixel defining layer overlapping a portion of the first electrode, such that the pixel defining layer exposes a portion of the first electrode and partitions pixel areas;
forming a block copolymer layer on the first electrode and the pixel defining layer;
patterning the block copolymer layer;
etching the pixel defining layer by using the patterned block copolymer layer as a mask, such that an uneven pixel defining layer with a plurality of defining layer grooves is formed; and
forming a light emitting layer on the first electrode and the uneven pixel defining layer.

2. The method as claimed in claim 1 , wherein forming the uneven pixel defining layer includes forming the defining layer grooves therein to be spaced a predetermined interval from each other.

3. The method as claimed in claim 1 , wherein forming the uneven pixel defining layer includes forming the defining layer grooves therein to have a uniform depth.

4. The method as claimed in claim 1 , wherein forming the uneven pixel defining layer includes forming the defining layer grooves in a top surface of the uneven pixel defining layer, such that no defining layer grooves are formed in a bottom surface of the uneven pixel defining layer.

5. The method as claimed in claim 1 , wherein forming the uneven pixel defining layer includes:
patterning the block copolymer layer to form a block copolymer pattern; and
etching the pixel defining layer by using the block copolymer pattern as a mask to form the uneven pixel defining layer having the defining layer grooves.

6. The method as claimed in claim 5 , wherein forming the block copolymer pattern is performed by providing ozone, oxygen plasma, or UV.

7. The method as claimed in claim 5 , wherein forming the block copolymer layer is performed by using a block copolymer including first repeating units and second repeating units different from the first repeating units.

8. The method as claimed in claim 7 , wherein forming the block copolymer pattern includes:
rearranging the first repeating units and the second repeating units to form a self-assembly structure in which the first repeating units and the second repeating units are alternately arranged; and
removing the first repeating units to form the block copolymer pattern.

9. The method as claimed in claim 8 , wherein forming the self-assembly structure is performed through thermal processing or solvent annealing.

10. The method as claimed in claim 8 , wherein, in the forming of the self-assembly structure, the block copolymer is self-assembled with a sphere, a cylinder, a lamellar, a gyroid, or a hexagonal perforated cylinder (HPL) structure.

11. The method as claimed in claim 8 , wherein forming the uneven pixel defining layer includes:
etching the pixel defining layer by using the second repeating units as a mask; and
removing the second repeating units.

12. The method as claimed in claim 11 , wherein etching the pixel defining layer includes etching the pixel defining layer without etching the first electrode.

13. The method as claimed in claim 11 , wherein removing the second repeating units includes removing the second repeating units disposed on the first electrode and the uneven pixel defining layer.

14. The method as claimed in claim 1 , wherein forming the uneven pixel defining layer includes exposing the portion of the first electrode.

15. The method as claimed in claim 1 , wherein forming the first electrode is performed so that the first electrode does not have grooves.

16. The method as claimed in claim 1 , further comprising
forming a second electrode on the uneven pixel defining layer and the light emitting layer, such that the second electrode includes an uneven second electrode with electrode grooves, and an even second electrode extending from the uneven second electrode and having no electrode grooves.

17. A display device, comprising:
a base substrate; and
a plurality of pixels on the base substrate, at least one pixel of the plurality of pixels including:
a thin film transistor on the base substrate,
a first electrode connected to the thin film transistor,
an uneven pixel defining layer overlapping a portion of the first electrode, the uneven pixel defining layer having a plurality of defining layer grooves,
a light emitting layer on the first electrode and the uneven pixel defining layer, and
a second electrode having an uneven second electrode with electrode grooves, and an even second electrode extending from the uneven second electrode and having no electrode grooves, the second electrode being disposed on the light emitting layer, wherein the uneven pixel defining layer includes an upper side surface and side surfaces defining an opening overlapping the light emitting layer, wherein the defining layer grooves include first defining layer grooves disposed on the upper side surface and second defining layer grooves disposed on the side surfaces, wherein the electrode grooves are disposed on an upper surface and a lower surface of the uneven second electrode, and wherein the electrode grooves do not overlap the light emitting layer.

18. The display device as claimed in claim 17 , wherein the first electrode does not have grooves.

19. The display device as claimed in claim 17 , wherein the defining layer grooves are defined in a top surface of the uneven pixel defining layer and are not defined in a bottom surface of the uneven pixel defining layer.

20. The display device as claimed in claim 17 , wherein the defining layer grooves are only on surfaces of the pixel defining layer facing the second electrode, the defining layer grooves being spaced apart from each other and having a predetermined depth in the pixel defining layer.

21. The display device as claimed in claim 17 , wherein the pixel defining layer has substantially flat surfaces between respective pairs of the defining layer grooves.

22. The display device as claimed in claim 21 , wherein the flat surfaces extend beyond bottom surfaces of the defining layer grooves.

23. The display device as claimed in claim 17 , wherein the light emitting layer is on the defining layer grooves and has an uneven surface that substantially conforms to the defining layer grooves.

Assignees

• Samsung Display Co Ltd

Inventors

• Park Seungwon
• Lee Baek Hee
• Choi Manseob
• Kang Minhyuck
• Lee Moongyu

Classifications

• H10K59/805

  Electrodes · CPC title

• H10K59/122

  Pixel-defining structures or layers, e.g. banks · CPC title

• G03F7/0002 Primary

  Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping · CPC title

• H01L51/5209

  Electricity · mapped topic

• H01L51/5225

  Electricity · mapped topic