Light emitting device and method for manufacturing the same

• US 20040072380A1
• Filed: 05/05/2003
• Published: 04/15/2004
• Est. Priority Date: 05/15/2002
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Osame, Mitsuaki, Murakami, Satoshi, Yamazaki, Shunpei
• Granted Patent: US 6,992,332 B2
• Time in Patent Office: Days
• US Class Current: 438/30
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/84 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 50/856 comprising reflective means
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/124 Insulating layers formed between TFT elements and OLED elements

Abstract

A light emitting element containing an organic compound has a disadvantage in that it tends to be deteriorated by various factors, so that the greatest problem thereof is to increase its reliability (make longer its life span). The present invention provides a method for manufacturing an active matrix type light emitting device and the configuration of such an active matrix type light emitting device having high reliability. In the method, a contact hole extending to a source region or a drain region is formed, and then an interlayer insulation film made of a photosensitive organic insulating material is formed on an interlayer insulation film. The interlayer insulation film has a curved surface on its upper end portion. Subsequently, an interlayer insulation film provided as a silicon nitride film having a film thickness of 20 to 50 nm is formed by a sputtering method using RF power supply.

Claims

1. A light emitting device including:

a pixel part having a light emitting element and a first thin film transistor between a first substrate and a second substrate; and

a driving circuit having a plurality of second thin film transistors,

wherein the light emitting element has a first electrode, a layer containing an organic compound on the first electrode, and a second electrode on the layer containing the organic compound,

wherein the first thin film transistor is coated with an interlayer insulation layer comprised an organic insulation film and an inorganic insulation film that covers the organic insulation film;

wherein a step is formed in an opening portion;

wherein the inorganic insulation film has a curved surface along an upper end portion of the organic insulation film; and

wherein an end portion of the first electrode is coated with an insulating material having a curved surface on an upper end portion.

2. A light emitting device according to claim 1,

wherein the first thin film transistor is electrically connected to the first electrode, and

wherein a wiring connected to one of a source region and a drain region of the thin film transistor is in contact with a part of the first electrode and is provided on the first electrode.

3. A light emitting device according to claim 1,

wherein the first thin film transistor electrically connected to the first electrode, and

wherein the first electrode is in contact with a part of a wiring connected to one of a source region and a drain region of the thin film transistor and is provided on the wiring.

4. A light emitting device according to claim 1,

wherein the first electrode has a slant face and a slanting angle is 30°

to 70°

.

5. A light emitting device according to claim 1,

wherein the insulating material has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

6. A light emitting device according to claim 1,

wherein the layer containing the organic compound is one of a material that emits red light, a material that emits green light, or a material that emits blue light.

7. A light emitting device according to claim 1,

wherein the layer containing the organic material is a material that emits white light and is used in combination with a color filter.

8. A light emitting device according to claim 1,

wherein the layer containing the organic compound is a material that emits monocolor light and is used in combination with a color-changing layer.

9. A light emitting device according to claim 1,

wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

10. A light emitting device including:

a pixel part having a light emitting element and a first thin film transistor between a first substrate and a second substrate; and

a driving circuit having a plurality of second thin film transistors,

wherein the light emitting element has a first electrode, a layer containing an organic compound on the first electrode, and a second electrode on the layer containing the organic compound;

wherein the first thin film transistor is coated with an interlayer insulation layer comprised of a laminate of an inorganic insulation film and an organic insulation film;

wherein a step is formed in an opening portion between a side surface of the inorganic insulation film and a side surface of the organic insulation film;

wherein an upper end of the organic film has a curved surface; and

wherein an end portion of the first electrode is coated with an insulating material having a curved surface on an upper end portion.

11. A light emitting device according to claim 10,

wherein the first thin film transistor is electrically connected to the first electrode, and

wherein a wiring connected to one of a source region and a drain region of the thin film transistor is in contact with a part of the first electrode and is provided on the first electrode.

12. A light emitting device according to claim 10,

wherein the first thin film transistor electrically connected to the first electrode, and

wherein the first electrode is in contact with a part of a wiring connected to one of a source region and a drain region of the thin film transistor and is provided on the wiring.

13. A light emitting device according to claim 10,

wherein the first electrode has a slant face and a slanting angle is 30°

to 70°

.

14. A light emitting device according to claim 10,

wherein the insulating material has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

15. A light emitting device according to claim 10,

wherein the layer containing the organic-compound is one of a material that emits red light, a material that emits green light, or a material that emits blue light.

16. A light emitting device according to claim 10,

wherein the layer containing the organic material is a material that emits white light and is used in combination with a color filter.

17. A light emitting device according to claim 10,

wherein the layer containing the organic compound is a material that emits monocolor light and is used in combination with a color-changing layer.

18. A light emitting device according to claim 10,

wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

19. A light emitting device including:

a pixel part having a light emitting element and a first thin film transistor between a first substrate and a second substrate; and

a driving circuit having a plurality of second thin film transistors,

wherein the light emitting element has a first electrode, a layer containing an organic compound on the first electrode, and a second electrode on the layer containing the organic compound,

wherein the first thin film transistor is coated with an interlayer insulation layer comprised of an organic insulation film and an inorganic insulation film that covers the organic insulation film;

wherein a step is formed in an opening portion;

wherein the inorganic insulation film has a curved surface along an upper end portion of the organic insulation film; and

wherein an end portion of the first electrode has a slant face, the slant face reflects light emitted from the layer containing the organic compound.

20. A light emitting device according to claim 19, wherein the first thin film transistor is electrically connected to the first electrode, and

wherein a wiring connected to one of a source region and a drain region of the thin film transistor is in contact with a part of the first electrode and is provided on the first electrode.

21. A light emitting device according to claim 19,

wherein the first thin film transistor electrically connected to the first electrode, and

wherein the first electrode is in contact with a part of a wiring connected to one of a source region and a drain region of the thin film transistor and is provided on the wiring.

22. A light emitting device according to claim 19,

wherein the first electrode has a slant face and a slanting angle is 30°

to 70°

.

23. A light emitting device according to claim 19,

wherein the insulating material has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

24. A light emitting device according to claim 19,

wherein the layer containing the organic compound is one of a material that emits red light, a material that emits green light, or a material that emits blue light.

25. A light emitting device according to claim 19,

wherein the layer containing the organic material is a material that emits white light and is used in combination with a color filter.

26. A light emitting device according to claim 19,

wherein the layer containing the organic compound is a material that emits monocolor light and is used in combination with a color-changing layer.

27. A light emitting device according to claim 19,

wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

28. A light emitting device including:

a pixel part having a light emitting element and a first thin film transistor between a first substrate and a second substrate; and

a driving circuit having a plurality of second thin film transistors,

wherein the light emitting element has a first electrode, a layer containing an organic compound on the first electrode, and a second electrode on the layer containing the organic compound;

wherein the first thin film transistor is coated with an interlayer insulation layer comprised of a laminate of an inorganic insulation film and an organic insulation film;

wherein a step is formed in an opening portion between a side surface of the inorganic insulation film and a side surface of the organic insulation film;

wherein an upper end of the organic film has a curved surface; and

wherein an end portion of the first electrode has a slant face, the slant face reflects light emitted from the layer containing the organic compound.

29. A light emitting device according to claim 28, wherein the first thin film transistor is electrically connected to the first electrode, and

wherein a wiring connected to one of a source region and a drain region of the thin film transistor is in contact with a part of the first electrode and is provided on the first electrode.

30. A light emitting device according to claim 28,

wherein the first thin film transistor electrically connected to the first electrode, and

wherein the first electrode is in contact with a part of a wiring connected to one of a source region and a drain region of the thin film transistor and is provided on the wiring.

31. A light emitting device according to claim 28,

wherein the first electrode has a slant face and a slanting angle is 30°

to 70°

.

32. A light emitting device according to claim 28,

wherein the insulating material has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

33. A light emitting device according to claim 28,

wherein the layer containing the organic compound is one of a material that emits red light, a material that emits green light, or a material that emits blue light.

34. A light emitting device according to claim 28,

wherein the layer containing the organic material is a material that emits white light and is used in combination with a color filter.

35. A light emitting device according to claim 28,

wherein the layer containing the organic compound is a material that emits monocolor light and is used in combination with a color-changing layer.

36. A light emitting device according to claim 28,

wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

37. A method for manufacturing a light emitting device, comprising the steps of:

forming an inorganic insulation film that covers a source region of a thin film transistor and a drain region of the thin film transistor;

forming a first contact hole extending to one of the source region and the drain region by etching the inorganic insulation film;

forming an organic insulation film on the inorganic insulation film;

forming a second contact hole extending to the one of the source region and the drain region by etching the organic insulation film;

forming a connecting electrode for making a connection with the one of the source region and the drain region;

forming a first electrode in contact with the connecting electrode;

forming a layer containing an organic compound on the first electrode; and

forming a second electrode on the layer containing the organic compound.

38. A method for manufacturing a light emitting device according to claim 37, wherein the first electrode functions as one of an anode and a cathode of a light emitting element.

39. A method for manufacturing a light emitting device according to claim 37, wherein the organic insulation film has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

40. A method for manufacturing the light emitting device according to claim 37, wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

41. A method for manufacturing a light emitting device, comprising the steps of:

forming an inorganic insulation film that covers a source region of a thin film transistor and a drain region of the thin film transistor;

forming at least two first contact holes extending to the source region and the drain region respectively by etching the inorganic insulation film;

forming a wiring for making a connection with one of the source region and the drain region;

forming an organic insulation film on the inorganic insulation film and the wiring;

forming at least two second contact holes by etching the organic insulation film, one of the two second contact holes is extending to the wiring and the other one of the two second contact holes is extending to the other one of the source region and the drain region;

forming at least two connecting electrodes, one of the two connecting electrodes is connected to the wiring and the other one of the two connecting electrodes is connected to the other one of the source region and the drain region;

forming a first electrode in contact with at least one of the two connecting electrodes;

forming a layer containing an organic compound on the first electrode; and

forming a second electrode on the layer containing the organic compound.

42. A method for manufacturing a light emitting device according to claim 41, wherein the first electrode functions as one of an anode and a cathode of a light emitting element.

43. A method for manufacturing a light emitting device according to claim 41, wherein the organic insulation film has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

44. A method for manufacturing the light emitting device according to claim 41, wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

45. A method for manufacturing a light emitting device, comprising the steps of:

forming an inorganic insulation film that covers a source region of a thin film transistor and a drain region of the thin film transistor;

forming a first contact hole extending to one of the source region and the drain region by etching the inorganic insulation film;

forming an organic insulation film on the inorganic insulation film;

forming a second contact hole extending to the one of the source region and the drain region by etching the organic insulation film;

forming an first electrode comprised of a laminate of metallic layers connecting to the one of the source region and the drain region;

forming an insulating material that covers an end portion of the first electrode;

thinning a center of the first electrode by etching using the insulating material as a mask such that a slant surface is exposed along an edge of the first electrode;

forming a layer containing an organic compound on the first electrode; and

forming a second electrode on the layer containing the organic compound.

46. A method for manufacturing a light emitting device according to claim 45, wherein the first electrode functions as one of an anode and a cathode of a light emitting element.

47. A method for manufacturing a light emitting device according to claim 45, wherein the organic insulation film has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

48. A method for manufacturing a light emitting device according to claim 45, wherein the insulating material has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

49. A method for manufacturing the light emitting device according to claim 45, wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

50. A method for manufacturing a light emitting device, comprising the steps of:

forming an inorganic insulation film that covers a source region of a thin film transistor and a drain region of the thin film transistor;

forming a silicon nitride film on the inorganic insulation film by a sputtering method;

forming a first contact hole extending to one of the source region and the drain region by etching the inorganic insulation film and the silicon nitride film;

forming an organic insulation film on the silicon nitride film;

forming a second contact hole extending to the one of the source region and the drain region by etching the organic insulation film;

forming a connecting electrode for making a connection with the one of the source region and the drain region;

forming a first electrode in contact with the connecting electrode;

forming a layer containing an organic compound on the first electrode; and

forming a second electrode on the layer containing the organic compound.

51. A method for manufacturing a light emitting device according to claim 50, wherein the first electrode functions as one of an anode and a cathode of a light emitting element.

52. A method for manufacturing a light emitting device according to claim 50, wherein the organic insulation film has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

53. A method for manufacturing the light emitting device according to claim 50, wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.

54. A method for manufacturing a light emitting device, comprising the steps of:

forming an inorganic insulation film that covers a source region of a thin film transistor and a drain region of the thin film transistor;

forming a first contact hole extending to one of the source region and the drain region by etching the inorganic insulation film;

forming an organic insulation film on the inorganic insulation film;

forming a silicon nitride film on the organic insulation film by a sputtering method;

forming a second contact hole extending to the one of the source region and the drain region by etching the organic insulation film and the silicon nitride film;

forming a connecting electrode for making a connection with the one of the source region and the drain region;

forming a first electrode in contact with the connecting electrode;

forming a layer containing an organic compound on the first electrode; and

forming a second electrode on the layer containing the organic compound.

55. A method for manufacturing a light emitting device according to claim 54, wherein the first electrode functions as one of an anode and a cathode of a light emitting element.

56. A method for manufacturing a light emitting device according to claim 54, wherein the organic insulation film has a curved surface with a curvature radius on an upper end portion, and the curvature radius is 0.2 μ

m to 3 μ

m.

57. A method for manufacturing the light emitting device according to claim 54, wherein the light emitting device is one selected from the group consisting of a video camera, a digital camera, a goggles-type display, a car navigation system, a personal computer, a DVD player, electronic playing equipment, and a personal digital assistant.