Light-emitting element and light-emitting device using the same

• US 20050116633A1
• Filed: 11/23/2004
• Published: 06/02/2005
• Est. Priority Date: 12/02/2003
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Nomura, Ryoji, Abe, Hiroko, Yamazaki, Shunpei
• Granted Patent: US 7,605,534 B2
• Time in Patent Office: Days
• US Class Current: 313/506
• CPC Class Codes: H10K 50/14 Carrier transporting layers
• CPC Class Codes: H10K 50/17 Carrier injection layers
• CPC Class Codes: H10K 50/171 Electron injection layers
• CPC Class Codes: H10K 50/18 Carrier blocking layers
• CPC Class Codes: H10K 85/311 Phthalocyanine
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine

Abstract

It is an object of the invention is to provide a light-emitting element in which failure of the light-emitting element due to separation can be controlled and stable luminescence can be obtained with high-efficiency and for a long stretch of time by controlling separation of layers constituting the light-emitting element. According to one aspect of a light-emitting element of the invention, the light-emitting element sandwiches a plurality of layers between a pair of electrodes, wherein at least one layer of the plurality of layers is a layer containing a substance selected from bismuth oxide, cobalt oxide, chromium oxide, copper oxide, nickel oxide, and titanium oxide, or at least one layer of layers different from a light-emitting layer among the plurality of layers is a mixed region of one substance selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide and an organic compound.

Claims

1. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein at least one of the plurality of layers is a layer containing a substance selected from bismuth oxide, cobalt oxide, chromium oxide, copper oxide, nickel oxide, and titanium oxide.

16. A light-emitting device having the light-emitting element according to claim 1.

27. A light emitting device according to claim 16, wherein the light emitting device is incorporated into an electronic device.

2. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein, a layer containing a substance selected from bismuth oxide, cobalt oxide, chromium oxide, copper oxide, nickel oxide, and titanium oxide is provided so as to be in contact at least with one of the electrodes of the plurality of layers.

17. A light-emitting device having the light-emitting element according to claim 2.

28. A light emitting device according to claim 17, wherein the light emitting device is incorporated into an electronic device.

3. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein the plurality of layers include a first layer having an organic compound;

a second layer having an organic compound; and

a layer containing a substance selected from bismuth oxide, cobalt oxide, chromium oxide, copper oxide, nickel oxide, and titanium oxide between the first layer and the second layer.

18. A light-emitting device having the light-emitting element according to claim 3.

29. A light emitting device according to claim 18, wherein the light emitting device is incorporated into an electronic device.

4. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein a layer containing a substance selected from bismuth oxide, cobalt oxide, chromium oxide, copper oxide, nickel oxide, and titanium oxide which is formed in a thickness enough for a tunneling current to flow is included between a first electrode operating as a cathode of the pair of electrodes and a layer having an organic compound.

19. A light-emitting device having the light-emitting element according to claim 4.

30. A light emitting device according to claim 19, wherein the light emitting device is incorporated into an electronic device.

5. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein a region at least containing an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide in a layer different from a light-emitting layer of the plurality of layers.

20. A light-emitting device having the light-emitting element according to claim 5.

31. A light emitting device according to claim 20, wherein the light emitting device is incorporated into an electronic device.

6. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein at least one of the plurality of layers is a hole transport region at least containing an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

21. A light-emitting device having the light-emitting element according to claim 6.

32. A light emitting device according to claim 21, wherein the light emitting device is incorporated into an electronic device.

7. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein at least one of the plurality of layers is an electron transport region at least containing an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

22. A light-emitting device having the light-emitting element according to claim 7.

33. A light emitting device according to claim 22, wherein the light emitting device is incorporated into an electronic device.

8. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein the plurality of layers include

a hole transport region comprising a hole transport material;

a first mixed region containing both the hole transport material and a light-emitting material;

a light-emitting region comprising the light-emitting material;

a second mixed region containing both an electron transport material and the light-emitting material; and

an electron transport region comprising the electron transport material,

wherein either the hole transport material or the electron transport material contains an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

10. The light-emitting element according to claim 8, wherein the first mixed region or the second mixed region contains 10 wt. % or more of any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

23. A light-emitting device having the light-emitting element according to claim 8.

34. A light emitting device according to claim 23, wherein the light emitting device is incorporated into an electronic device.

9. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein the plurality of layers include

a hole transport region comprising a hole transport material;

a first mixed region containing both the hole transport material and a first organic compound;

a light-emitting region containing both the first organic compound and a second organic compound;

a second mixed region containing both an electron transport material and the first organic compound; and

an electron transport region comprising the electron transport material,

wherein the second organic compound is a luminous body, and

wherein either the hole transport material or the electron transport material contains an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

11. The light-emitting element according to claim 9, wherein the first mixed region or the second mixed region contains 10 wt. % or more of any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

24. A light-emitting device having the light-emitting element according to claim 9.

35. A light emitting device according to claim 24, wherein the light emitting device is incorporated into an electronic device.

12. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein the plurality of layers include

a hole injection region comprising a hole injection material;

a first mixed region containing both the hole injection material and a hole transport material;

a hole transport region comprising the hole transport material;

a second mixed region containing both the hole transport material and a light-emitting material;

a light-emitting region comprising the light-emitting material;

a third mixed region containing both the light-emitting material and an electron transport material;

an electron transport region comprising the electron transport material;

a fourth mixed region containing both the electron transport material and a hole blocking material;

a hole blocking region comprising the hole blocking material;

a fifth mixed region containing both the hole blocking material and an electron injection material; and

an electron injection region comprising the electron injection material,

wherein any one of the hole injection material, the hole transport material, the electron transport material, or the electron injection material contains an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

14. The light-emitting element according to claim 12, wherein any one of the first mixed region, the second mixed region, the third mixed region, the fourth mixed region, or the fifth mixed region contains 10 wt. % or more of any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

25. A light-emitting device having the light-emitting element according to claim 12.

36. A light emitting device according to claim 25, wherein the light emitting device is incorporated into an electronic device.

13. A light-emitting element comprising:

a pair of electrodes; and

a plurality of layers sandwiched between the pair of electrodes,

wherein the plurality of layers include

a hole injection region comprising a hole injection material;

a first mixed region containing both the hole injection material and a hole transport material;

a hole transport region comprising the hole transport material;

a second mixed region containing both the hole transport material and a first organic compound;

a light-emitting region containing both the first organic compound and a second organic compound;

a third mixed region containing both the first organic compound and an electron transport material;

an electron transport region comprising the electron transport material;

a fourth mixed region containing both the electron transport material and a hole blocking material;

a hole blocking region comprising the hole blocking material;

a fifth mixed region containing both the hole blocking material and an electron injection material; and

an electron injection region comprising the electron injection material,

wherein the second organic compound is a luminous body, and

wherein any one of the hole injection material, the hole transport material, the electron transport material, or the electron injection material contains an organic compound and any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

15. The light-emitting element according to claim 13, wherein any one of the first mixed region, the second mixed region, the third mixed region, the fourth mixed region, or the fifth mixed region contains 10 wt. % or more of any one of compounds selected from bismuth oxide, cobalt oxide, copper oxide, magnesium oxide, nickel oxide, zinc oxide, and titanium oxide.

26. A light-emitting device having the light-emitting element according to claim 13.

37. A light emitting device according to claim 26, wherein the light emitting device is incorporated into an electronic device.