Organic electroluminescent device and manufacturing method therefor

• US 6,853,130 B2
• Filed: 03/19/2001
• Issued: 02/08/2005
• Est. Priority Date: 03/21/2000
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Morii, Katsuyuki
• Primary Examiner(s): Patel, Nimeshkumar D.
• Assistant Examiner(s): LEURIG, SHARLENE L
• Application Number:
  US09/810,233
• Publication Number:
  US 20020039730A1
• Time in Patent Office: 1,422 Days
• Field of Search: 313/311, 313/498, 313/503, 313/504, 313/506, 428/690
• US Class Current: 313/503
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: H10K 50/826 Multilayers, e.g. opaque multilayers
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/844 Encapsulations

Abstract

An organic electroluminescent device includes an anode, a light-emitting layer, and a cathode, which has a structure formed by sequentially laminating, from the light-emitting layer side, a first cathode formed of a material having a work function of 3.0 eV or less, and a second cathode, formed of a material having a work function higher than that of the first cathode, so that the total thickness of the first and the second cathodes is 100 angstroms or less. These elements are stacked on a substrate, and light is emitted to an exterior of the device via at least the cathode.

Claims

1. An organic electroluminescent device, comprising:

a substrate;

an anode;

a light-emitting layer formed of an organic material; and

a cathode including a first cathode formed of a material having a work function of 3.0 eV or less and a second cathode formed of a material having a work function higher than the work function of the first cathode, the first and second cathodes being sequentially stacked in this order from the side of the light-emitting layer, a total thickness of the first and the second cathodes being 100 angstroms or less, and light being emitted to an exterior of the device via at least the cathode, the thickness y (angstrom) of the first cathode being such that 55≦

y≦

65, the thickness z (angstrom) of the second cathode being such that 10≦

z≦

20.

2. The organic electroluminescent device according to claim 1, the device at the cathode being sealed by a sealing layer formed of a light transmissive material.

3. The organic electroluminescent device according to claim 1, the first cathode including Ca.

4. The organic electroluminescent device according to claim 1, the second cathode including A1.

5. The organic electroluminescent device according to claim 1, the organic material forming the light-emitting layer being a polymeric material.

6. The organic electroluminescent device according to claim 1, the first cathode including Au.

7. The organic electroluminescent device according to claim 2, the sealing layer including Au.

8. The organic electroluminescent device according to claim 2, a thickness of the sealing layer including LiF being more than 300 angstrom and less than 500 angstrom.