Light emitting element with improved layer thickness uniformity

Patent metadata

Field	Value
Publication number	US-9595675-B2
Application number	US-201514666936-A
Country	US
Kind code	B2
Filing date	Mar 24, 2015
Priority date	Mar 27, 2014
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

A light-emitting element includes an anode, a cathode, a hole transporting layer provided between the anode and cathode, a light-emitting layer provided in contact with the hole transporting layer between the anode and cathode, where the surface of the light-emitting layer side of the hole transporting layer is formed in a shape having a part in which the distance with the reference surface along the anode changes in a continuous or step-wise manner, and the surface of the opposite side to the hole transporting layer of the light-emitting layer is formed so as to have the same shape as the surface of the light-emitting layer of the hole transporting layer.

First claim

What is claimed is:

1. A light-emitting element, comprising:
a first electrode;
a second electrode;
a first layer provided between the first electrode and the second electrode;
a second layer provided in contact with the first layer between the first layer and the second electrode;
a reference surface of the first electrode that faces the first layer;
a first surface of the first layer that is in contact with the second layer, the first surface being formed having a part in which a distance between the first surface and the reference surface changes in a continuous or step-wise manner; and
a second surface of the second layer disposed on an opposite side of the second layer from the first layer, the second surface being formed so as to have a same shape as the first surface,
wherein in a first region covering at least 90% of the second layer in a width direction of the second layer, a difference between the distance between the first surface and the reference surface and a distance between the second surface and the reference surface is within a range of ±10% with respect to an average value of the difference within the first region.

2. The light-emitting element according to claim 1 ,
wherein the second layer has a long shape when viewed in a direction in which the first electrode and the second electrode overlap, and
in a second region covering at least 90% of the second layer in a length direction of the second layer, a difference between the distance between the first surface and the reference surface and the distance between the second surface and the reference surface is within a range of ±10% with respect to an average value of the difference within the second region.

3. A light-emitting device comprising the light-emitting element according to claim 2 .

4. An electronic apparatus comprising the light-emitting element according to claim 2 .

5. The light-emitting element according to claim 1 ,
wherein the first electrode is an anode,
the second electrode is a cathode,
the first layer is a hole injection layer or a hole transporting layer; and
the second layer is a light-emitting layer.

6. A light-emitting device comprising the light-emitting element according to claim 5 .

7. An electronic apparatus comprising the light-emitting element according to claim 5 .

8. A light-emitting device comprising the light-emitting element according to claim 1 .

9. An electronic apparatus comprising the light-emitting element according to claim 1 .

10. A method of manufacturing the light-emitting element according to claim 1 , comprising:
forming the first electrode;
forming the first layer using a liquid phase process on the reference surface of the first electrode;
forming the second layer using a liquid phase process on the first layer such that the second surface has the same shape as the first surface; and
forming a the second electrode on the opposite side of the second layer from the first layer.

11. The method of manufacturing the light-emitting element according to claim 10 ,
wherein the first layer and the second layer are formed in a same divided bank.

12. The method of manufacturing the light-emitting element according to claim 11 ,
wherein the forming of the second layer is performed by fixing after applying a liquid including a material that configures the second layer or a precursor thereof on the first layer; and
in the forming of the second layer, a contact angle of the precursor with respect to the first layer is equal to or smaller than a contact angle of the precursor with respect to the bank.

13. The method of manufacturing the light-emitting element according to claim 12 ,
wherein B/A is 0.003 ng/μm 2 or more and 0.006 ng/μm 2 or less when an area in plan view in the bank is A [μm 2 ] and an amount of liquid applied on the first layer when forming the second layer is B[ng].

14. The method of manufacturing the light-emitting element according to claim 12 ,
wherein drying is performed by reducing pressure from normal pressure to 5 Pa within 5 minutes after applying the precursor on the first layer.

Assignees

• Seiko Epson Corp

Inventors

• Sago Takumi
• Uchida Masahiro
• Ishida Kohei
• Watanabe Shotaro

Classifications

• H01L51/5088

  Electricity · mapped topic

• H01L51/5056

  Electricity · mapped topic

• H01L51/5092

  Electricity · mapped topic

• H01L27/3246

  Electricity · mapped topic

• H01L51/0005 Primary

  Electricity · mapped topic