Granted Patent B2

US 12,219,873 · App. 18/420,214 · Granted Feb 4, 2025

Inventors: Satoshi Seo (Kanagawa, JP); Tsunenori Suzuki (Kanagawa, JP); Naoaki Hashimoto (Kanagawa, JP)

Assignee: Semiconductor Energy Laboratory Co., Ltd.

H10K85/6572H10K50/11H10K50/155H10K50/166H10K50/841H10K85/615H10K85/654H10K2101/30H10K2101/40

Abstract

Claims (35)

1. A light-emitting element comprising:

an anode;

a cathode; and

an EL layer between the anode and the cathode,

wherein the EL layer comprises a light-emitting layer, a first electron-transport layer, and a second electron-transport layer,

wherein the first electron-transport layer is between the light-emitting layer and the second electron-transport layer,

wherein the light-emitting layer has a region in contact with the first electron-transport layer,

wherein the second electron-transport layer has a region in contact with the first electron-transport layer,

wherein the light-emitting layer comprises a fluorescent substance and a host material,

wherein the first electron-transport layer comprises a first material,

wherein the second electron-transport layer comprises a second material,

wherein a LUMO level of the host material is higher than a LUMO level of the first material,

wherein a LUMO level of the second material is higher than the LUMO level of the first material,

wherein the host material is a substance including an anthracene skeleton,

wherein the first material is a substance comprising any one of a dibenzoquinoxaline skeleton, a dibenzoquinazoline skeleton, and a pyrimidine skeleton, and

wherein the second material is a substance comprising any of a phenanthroline skeleton, a bipyridine skeleton and a pyridine skeleton.

2. The light-emitting element according to claim 1 ,

wherein the second electron-transport layer is in contact with the cathode.

3. The light-emitting element according to claim 1 ,

wherein the EL layer further comprises a hole-injection layer,

wherein the hole-injection layer is in contact with the anode, and

wherein the hole-injection layer comprises an organic acceptor material.

4. The light-emitting element according to claim 3 ,

wherein the organic acceptor material is 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene.

5. The light-emitting element according to claim 1 ,

wherein the fluorescent substance exhibits blue light.

6. A light-emitting device comprising:

the light-emitting element according to claim 1 ; and

at least one of a transistor and a substrate.

7. An electronic device comprising:

the light-emitting device according to claim 6 ; and

at least one of a sensor, an operation button, a speaker, and a microphone.

8. A lighting device comprising:

the light-emitting device according to claim 6 ; and

a housing.

Priority Claims (2)

Continuity (4)

References Cited (80)