Organic light emitting element and light emitting device using the element

• US 7,199,515 B2
• Filed: 05/31/2002
• Issued: 04/03/2007
• Est. Priority Date: 06/01/2001
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Seo, Satoshi, Yamazaki, Shunpei, Murakami, Masakazu
• Primary Examiner(s): Patel; Nimeshkumar D.
• Assistant Examiner(s): MACCHIAROLO, PETER J
• Application Number:
  US10/158,233
• Publication Number:
  US 20030015960A1
• Time in Patent Office: 1,768 Days
• Field of Search: 428/690, 428/917, 313/498, 313502-506, 313/509
• US Class Current: 313/504
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

An organic light emitting element which can employ non-sublimable (non-volatile) or insoluble materials while keeping the same level of light emission as prior art is provided. Dispersive particles (202a) of an insoluble organic material that is dispersed in a solvent (201) in which a soluble organic material (203a) is dissolved is applied to a substrate (200) that has an electrode. Then, the solvent (201) is vaporized by heat treatment to form a uniform film (203b) of the soluble organic material in which aggregations (clusters) of the insoluble organic material are scattered. Since the soluble organic material film (203b) is thoroughly uniform, defects such as breakdown can be avoided to make it a fully functional organic light emitting element.

Claims

1. An active matrix type display device comprising:

at least one thin film transistor; and

a light emitting element electrically connected to the thin film transistor, said light emitting element comprising;

an anode;

a cathode, and

an organic compound layer sandwiched between the anode and the cathode, the organic compound layer comprising at least one host material and at least one guest material, the host material and the guest material include an organic compound,

wherein the host material forms an amorphous film and the guest material is scattered in the amorphous film in the form of granules which are aggregations of material molecules, the granules have a diameter smaller than a thickness of the organic compound layer, and

wherein the host material is soluble in an organic solvent and the guest material is insoluble in the organic solvent.

2. The active matrix type display device according to claim 1, wherein the guest material is a luminous material.

3. The active matrix type display device according to claim 1, wherein the guest material is a material that emits light when returning from triplet excitation.

4. The active matrix type display device according to claim 1, wherein the host material is a material is a high molecular weight material soluble in an organic solvent and the guest material is insoluble in the organic solvent.

5. The active matrix type display device according to claim 4, wherein the guest material is a luminous material.

6. The active matrix type display device according to claim 4, wherein the guest material is a material that emits light when returning from triplet excitation.

7. An electric appliance comprising the active matrix type display device of claim 1, wherein the electric appliance is selected from the group consisting of a video camera, a digital still camera, a lap-top computer, a personal computer, a goggle type display, a mobile telephone, a navigation system, an audio reproducing device, a portable computer, a game machine, a portable information terminal, and an image reproducing apparatus.

8. The active matrix type display device according to claim 1, wherein the organic compound layer is formed by applying a solution including the host material and the guest material by spin coating.

9. An active matrix type display device comprising:

a thin film transistor;

a light emitting element electrically connected to the thin film transistor, said light emitting element comprising;

an anode;

a cathode, and

an organic compound layer placed between the anode and the cathode, the organic compound layer comprising at least a first organic compound and a second organic compound,

wherein the first organic compound forms an amorphous film and the second organic compound is scattered in the amorphous film in the form of granules which are aggregations of material molecules, the granules have a diameter smaller than a thickness of the organic compound layer, and

wherein the first organic compound is soluble in a solvent and the second organic compound is insoluble in the solvent.

10. The active matrix type display device according to claim 9, wherein the second organic compound emits fluorescent light or phosphorescent light.

11. The active matrix type display device according to claim 9, wherein the organic compound layer has a thickness of 1 nm or more and 1 μ

m or less.

12. An electric appliance comprising the active matrix type display device of claim 9, wherein the electric appliance is selected from the group consisting of a video camera, a digital still camera, a lap-top computer, a personal computer, a goggle type display, a mobile telephone, a navigation system, an audio reproducing device, a portable computer, a game machine, a portable information terminal, and an image reproducing apparatus.

13. The active matrix type display device according to claim 9, wherein the the second organic compound is a material that emits light when returning from triplet excitation.

14. The active matrix type display device according to claim 9, wherein the organic compound layer is formed by applying a solution including the first organic compound and the second organic compound by spin coating.

15. An active matrix type display device comprising:

at least one thin film transistor; and

a light emitting element electrically connected to the thin film transistor, said light emitting element comprising;

an anode;

a cathode, and

an organic compound layer sandwiched between the anode and the cathode, the organic compound layer comprising at least one host material and at least one guest material,

wherein the host material forms an amorphous film and the guest material is scattered in the amorphous film in the form of granules which are aggregations of material molecules, the granules have a diameter smaller than a thickness of the organic compound layer,

wherein the guest material comprises at least one selected from the group consisting of a pigment, a condensed polycyclic organic compound, an orthometal complex of iridium, and a conjugate polymer having no substituent, and

wherein the host material is soluble in an organic solvent and the guest material is insoluble in the organic solvent.

16. The active matrix type display device according to claim 15, wherein the guest material is a luminous material.

17. The active matrix type display device according to claim 15, wherein the guest material is a material that emits light when returning from triplet excitation.

18. The active matrix type display device according to claim 15, wherein the host material is a material is a high molecular weight material soluble in an organic solvent and the guest material is insoluble in the organic solvent.

19. The active matrix type display device according to claim 18, wherein the guest material is a luminous material.

20. The active matrix type display device according to claim 18, wherein the guest material is a material that emits light when returning from triplet excitation.

21. The active matrix type display device according to claim 15, wherein the guest material comprises at least one selected from the group consisting of Qd, CuPc, BCP, Ir(ppy)3, PPV, PNV, Phenyl-PPV, PT, PPT, PPP, and PF.

22. An electric appliance comprising the active matrix type display device of claim 15, wherein the electric appliance is selected from the group consisting of a video camera, a digital still camera, a lap-top computer, a personal computer, a goggle type display, a mobile telephone, a navigation system, an audio reproducing device, a portable computer, a game machine, a portable information terminal, and an image reproducing apparatus.

23. The active matrix type display device according to claim 15, wherein the organic compound layer is formed by applying a solution including the host material and the guest material by spin coating.

24. An active matrix type display device comprising:

a thin film transistor; and

a light emitting element electrically connected to the thin film transistor, said light emitting element comprising;

an anode;

a cathode, and

an organic compound layer placed between the anode and the cathode, the organic compound layer comprising at a first organic compound and a second organic compound,

wherein the first organic compound forms an amorphous film and the second organic compound is scattered in the amorphous film in the form of granules which are aggregations of material molecules, the granules have a diameter smaller than a thickness of the organic compound layer,

wherein the second organic compound comprises at least one selected from the group consisting of a pigment, a condensed polycyclic organic compound, an orthometal complex of iridium, and a conjugate polymer having no substituent, and

wherein the first organic compound is soluble in a solvent and the second organic compound is insoluble in the solvent.

25. The active matrix type display device according to claim 24, wherein the second organic compound emits fluorescent light or phosphorescent light.

26. The active matrix type display device according to claim 24, wherein the organic compound layer has a thickness of 1 nm or more and 1 pm or less.

27. The active matrix type display device according to claim 24, wherein the second organic compound comprises at least one selected from the group consisting of Qd, CuPc, BCP, Ir(ppy)3, PPV, PNV, Phenyl-PPV, PT, PPT, PPP, and PF.

28. An electric appliance comprising the active matrix type display device of claim 24, wherein the electric appliance is selected from the group consisting of a video camera, a digital still camera, a lap-top computer, a personal computer, a goggle type display, a mobile telephone, a navigation system, an audio reproducing device, a portable computer, a game machine, a portable information terminal, and an image reproducing apparatus.

29. The active matrix type display device according to claim 24, wherein the second organic compound is a material that emits light when returning from triplet excitation.

30. The active matrix type display device according to claim 24, wherein the organic compound layer is formed by applying a solution including the first organic compound and the second organic compound by spin coating.