Electrophoretic display device and method of fabrication thereof
View Patent ↗Disclosed herein is a method of fabricating an electrophoretic display device for reducing the fabrication cost and simplifying the fabrication process, and the method may include providing a substrate comprising a display region arranged with a plurality of pixels and a non-display region; forming a thin-film transistor on a first substrate; forming a passivation layer on the substrate formed with the thin-film transistor; forming a pixel electrode in the display region on the passivation layer and forming a partition wall in the non-display region; filling an electrophoretic material in a pixel inside the partition wall on the passivation layer; applying a sealing material to an upper portion of the electrophoretic material to form a sealing layer; depositing a transparent conductive material on the sealing layer to form a common electrode; and adhering the protection layer to an upper portion of the common electrode.
1. A method of fabricating an electrophoretic display device, the method comprising:
providing a substrate including a display region comprising a plurality of pixels and a non-display region at the outside of the display region;
forming a thin-film transistor at each pixel on the substrate;
forming a passivation layer on the substrate to cover the thin-film transistor;
forming a pixel electrode for each pixel and a partition wall between pixels on the passivation layer;
forming an electrophoretic layer in a pixel between partition walls on the passivation layer;
forming a sealing layer at least on an upper portion of the electrophoretic layer;
directly coating a transparent conductive material on the sealing layer to form a common electrode;
directly coating a transparent adhesive agent on an upper surface of the common electrode; and
attaching a protection film to the upper surface of the common electrode by the transparent adhesive agent.
2. The method of claim 1 , wherein the forming the sealing layer forms the sealing layer on an upper portion of the electrophoretic layer and a top surface of the partition walls.
3. The method of claim 1 , further comprising forming an interlayer between the electrophoretic layer and the sealing layer.
4. The method of claim 3 , wherein the interlayer includes Methyl Ethyl Ketone.
5. The method of claim 1 , wherein the forming a pixel electrode and a partition wall comprises:
forming a pixel electrode at each pixel on the passivation layer; and
forming a partition wall between pixels on the passivation layer.
6. The method of claim 1 , wherein the forming a pixel electrode and a partition wall comprises:
forming a partition wall between pixels on the passivation layer; and
forming a pixel electrode at each pixel on the passivation layer.
7. The method of claim 6 , wherein the pixel electrode is further formed on a side surface of the partition wall.
8. The method of claim 6 or 7 , wherein the forming a partition wall comprises:
forming an insulation layer on the passivation layer; and
removing part of the insulation layer corresponding to the pixel using any one of a photolithography process, a mold process, and an imprint process.
9. The method of claim 1 , wherein the electrophoretic material comprises charged white particles and charged black particles.
10. The method of claim 9 , wherein the electrophoretic material further comprises a dispersive medium.
11. The method of claim 10 , wherein the dispersive medium is emulsion polymer or air.
12. The method of claim 10 , wherein the dispersive medium is non-polarized organic medium.
13. The method of claim 1 , wherein the electrophoretic material comprises charged color particles.
14. The method of claim 1 , wherein the forming an electrophoretic layer comprises filling an electrophoretic material between the partition walls using any one of a dropping method, a squeeze method, a casting printing method, a bar-coating printing method, a screen printing method, and a mold printing method.
15. The method of claim 1 , wherein the forming a sealing layer comprises:
applying a sealing material to an upper portion of the electrophoretic layer; and
curing the sealing material.
16. The method of claim 15 , wherein the sealing material is formed of at least one material selected from a group consisting of an acrylic transparent organic resin, an overcoat transparent organic material, and a hybrid transparent organic material.
17. The method of claim 15 , wherein the curing the sealing material comprises irradiating ultraviolet rays on the sealing material.
18. The method of claim 15 , wherein the curing a sealing material comprises applying heat of less than 80° C. to the sealing material.
19. The method of claim 1 , wherein the sealing layer is formed with a thickness of 10 μm or less.
20. The method of claim 1 , wherein the common electrode is comprises a soluble transparent conductive material.
21. The method of claim 20 , wherein the soluble transparent conductive material comprises indium gallium zinc oxide (IGZO) and zinc oxide (ZnO).
22. The method of claim 1 , wherein the common electrode comprises indium tin oxide (ITO) and indium zinc oxide (IZO).
23. The method of claim 22 , wherein the ITO and IZO are deposited by a sputtering method in a room temperature.
24. The method of claim 1 , wherein the common electrode comprises tin oxide (SnO).
25. The method of claim 24 , wherein the SnO is deposited by a chemical vapor deposition (CVD) method.
26. The method of claim 1 , wherein the common electrode comprises carbon nanotubes.
27. The method of claim 1 , wherein the protection film comprises material selected from a group consisting of: a polystyrene (PS) film, a polyethylene (PE) film, a polyethylene naphthalate (PEN) film, and a polyimide (PI) film.
28. An electrophoretic display device, the device comprising:
a substrate including a display region comprising a plurality of pixels and a non-display region at the outside of the display region;
a thin-film transistor at each pixel on the substrate;
a passivation layer on the substrate to cover the thin-film transistor;
a partition wall on the passivation layer in the display region to define a pixel;
a pixel electrode at each pixel on the passivation layer and a side surface of the partition wall;
an electrophoretic layer between the partition walls within a pixel;
a sealing layer at least on an upper portion of the electrophoretic layer;
a common electrode on the sealing layer; and
a protection layer formed on the common electrode.
29. The device of claim 28 , wherein the electrophoretic material comprises charged white particles and charged black particles.
30. The device of claim 28 , wherein the electrophoretic material comprises charged color particles.
31. The device of claim 29 or 30 , wherein the electrophoretic material further comprises a dispersive medium.
32. The device of claim 28 , wherein the sealing layer comprises at least one material selected from a group consisting of: an acrylic transparent organic resin, an overcoat transparent organic material, and a hybrid transparent organic material.
33. The device of claim 28 , wherein the common electrode comprises material selected from a group consisting of: indium gallium zinc oxide (IGZO), zinc oxide (ZnO), indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO), and carbon nanotube.
34. The device of claim 28 , wherein the protection film comprises material selected from a group consisting of: a polystyrene (PS) film, a polyethylene (PE) film, a polyethylene naphthalate (PEN) film, and a polyimide (PI) film.
35. The device of claim 28 , further comprising an interlayer between the electrophoretic layer and the sealing layer.
36. The device of claim 35 , wherein the interlayer includes Methyl Ethyl Ketone.