Organic light emitting diode, manufacturing method thereof, display substrate and display apparatus

Patent metadata

Field	Value
Publication number	US-12364094-B2
Application number	US-202117801623-A
Country	US
Kind code	B2
Filing date	Oct 28, 2021
Priority date	Feb 26, 2021
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

An organic light emitting diode, a manufacturing method thereof, a display substrate and a display apparatus are disclosed. The organic light emitting diode includes: a first electrode and a second electrode opposite to each other; and a first hole transport layer, a first electron blocking layer, a blue emission layer, at least one first hole blocking layer, and a first electron transport layer, which are between the first electrode and the second electrode and sequentially arranged in a direction approaching the second electrode, wherein a total thickness of all the at least one first hole blocking layer is greater than a thickness of the first electron blocking layer.

First claim

What is claimed is:

1. An organic light emitting diode, comprising:
a first electrode and a second electrode opposite to each other; and
a first hole transport layer, a first electron blocking layer, a blue emission layer, at least one first hole blocking layer, and a first electron transport layer, which are between the first electrode and the second electrode and sequentially arranged in a direction approaching the second electrode, wherein a total thickness of all the at least one first hole blocking layer is greater than a thickness of the first electron blocking layer,
wherein a material of the at least one first hole blocking layer comprises a planar aromatic compound having a large conjugated structure.

2. The organic light emitting diode according to claim 1 , wherein the at least one first hole blocking layer comprises a plurality of first hole blocking layers, which are made of a same material.

3. The organic light emitting diode according to claim 1 , wherein the at least one first hole blocking layer comprises a plurality of first hole blocking layers, which are made of different materials; and
electron mobilities of the plurality of first hole blocking layers are increased layer by layer in a direction approaching the first electron transport layer.

4. The organic light emitting diode according to claim 3 , wherein the plurality of first hole blocking layers comprise two first hole blocking layers, wherein an electron mobility of one of the two first hole blocking layers is in a range of 1.5×10 −6 cm 2 /Vs to 2.5×10 −6 cm 2 /Vs, and an electron mobility of the other of the two first hole blocking layers is in a range of 7.0×10 −6 cm 2 /Vs to 8.0×10 −6 cm 2 /Vs.

5. The organic light emitting diode according to claim 1 , wherein the total thickness of all the at least one first hole blocking layer is 1.5 or more times the thickness of the first electron blocking layer.

6. The organic light emitting diode according to claim 1 , wherein a thickness of each of the at least one first hole blocking layer is in a range of 2 nm to 10 nm.

7. A display substrate, comprising:
a base substrate; and
a plurality of organic light emitting diodes on the base substrate, wherein the plurality of organic light emitting diodes comprise at least one blue organic light emitting diode which is the organic light emitting diode according to claim 1 .

8. The display substrate according to claim 7 , wherein the plurality of organic light emitting diodes further comprises a red organic light emitting diode and a green organic light emitting diode,
the red organic light emitting diode comprises:
a third electrode and a fourth electrode opposite to each other; and
a second hole transport layer, a second electron blocking layer, a red emission layer, a second hole blocking layer, and a second electron transport layer, which are between the third electrode and the fourth electrode and sequentially arranged in a direction approaching the fourth electrode,
the green organic light emitting diode comprises:
a fifth electrode and a sixth electrode opposite to each other; and
a third hole transport layer, a third electron blocking layer, a green emission layer, a third hole blocking layer, and a third electron transport layer, which are between the fifth electrode and the sixth electrode and sequentially arranged in a direction approaching the sixth electrode, and wherein the third electrode, the fifth electrode and the first electrode are in a same layer; the fourth electrode, the sixth electrode and the second electrode are in a same layer; the second hole transport layer, the third hole transport layer and the first hole transport layer are in a same layer; the second electron transport layer, the third electron transport layer and the first electron transport layer are in a same layer; and the second hole blocking layer and the third hole blocking layer each are in a same layer with the at least one first hole blocking layer in a one-to-one correspondence.

9. The display substrate according to claim 8 , wherein a thickness of the green emission layer is greater than a thickness of the blue emission layer and less than a thickness of the red emission layer.

10. The display substrate according to claim 8 , wherein a thickness of the third electron blocking layer is greater than a thickness of the first electron blocking layer and less than a thickness of the second electron blocking layer.

11. The display substrate according to claim 7 , wherein the first electrode is between the blue emission layer and the base substrate, and the second electrode is on a side of the blue emission layer away from the base substrate.

12. A display apparatus, comprising the display substrate according to claim 7 .

13. A method for manufacturing the organic light emitting diode according to claim 1 , comprising:
forming the first electrode;
forming the first hole transport layer, the first electron blocking layer, the blue emission layer, the at least one first hole blocking layer, and the first electron transport layer, respectively, wherein the first hole transport layer, the first electron blocking layer, the first emission layer, the at least one first hole blocking layer, and the first electron transport layer are arranged in a direction leaving the first electrode; and a total thickness of all the at least one first hole blocking layer is greater than a thickness of the first electron blocking layer; and
forming the second electrode, wherein the second electrode is arranged opposite to the first electrode.

14. The method according to claim 13 , wherein each of the at least one first hole blocking layer is formed by an evaporation process.

15. The organic light emitting diode according to claim 2 , wherein the total thickness of all the at least one first hole blocking layer is 1.5 or more times the thickness of the first electron blocking layer.

16. The organic light emitting diode according to claim 2 , wherein a thickness of each of the at least one first hole blocking layer is in a range of 2 nm to 10 nm.

17. The organic light emitting diode according to claim 3 , wherein the total thickness of all the at least one first hole blocking layer is 1.5 or more times the thickness of the first electron blocking layer.

Assignees

• Boe Technology Group Co Ltd

Inventors

• Hao Yanjun
• Qu Caiyu
• Wen Guanyin
• Wu Songquan
• Zuo Pengfei
• Du Xiaobo
• Li Yansong

Classifications

• H10K71/16

  using physical vapour deposition [PVD], e.g. vacuum deposition or sputtering · CPC title

• H10K59/35

  comprising red-green-blue [RGB] subpixels · CPC title

• H10K71/60

  Forming conductive regions or layers, e.g. electrodes · CPC title

• H10K50/181 Primary

  Electron blocking layers · CPC title

• H10K2102/351

  Thickness · CPC title