Organic EL element and method of making the same

• US 6,720,735 B2
• Filed: 11/14/2001
• Issued: 04/13/2004
• Est. Priority Date: 11/15/2000
• Status: Expired due to Fees

• Current Assignee: Pioneer Corporation
• Original Assignee: Pioneer Corporation
• Inventors: Miyaguchi, Satoshi, Okuda, Yoshiyuki, Tsuchida, Masami
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): TRAN, THUY V
• Application Number:
  US09/987,363
• Publication Number:
  US 20020125830A1
• Time in Patent Office: 881 Days
• Field of Search: 315/169.3, 315/169.1, 313/506, 313/505, 313/498, 313/502
• US Class Current: 315/169.3
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0885 Pixel comprising a non-linear two-terminal element alone in series with each display pixel element
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2330/04 Display protection
• CPC Class Codes: G09G 3/3216 using a passive matrix
• CPC Class Codes: G09G 3/3266 Details of drivers for scan electrodes
• CPC Class Codes: G09G 3/3283 in which the data driver supplies a variable data current for setting the current through, or the voltage across, the light-emitting elements
• CPC Class Codes: H10K 59/17 Passive-matrix OLED displays
• CPC Class Codes: H10K 59/179 Interconnections, e.g. wiring lines or terminals

Abstract

The present invention relates to an organic EL light emitting element that can suppress deterioration of a light emitting layer and can provide a high light-emission intensity. This organic EL light emitting element includes a light emitting part and a rectifier part connected in series to the light emitting part. Both of the light emitting and rectifier parts include organic thin layers. The electrostatic capacity of the rectifier part is smaller than that of the light emitting part.

Claims

1. An organic electroluminescence element comprising:

a single light emitting part having an organic thin layer; and

a single rectifier part connected in series to the light emitting part, wherein the rectifier part has an organic thin layer, and an electrostatic capacity of the rectifier part is smaller than an electrostatic capacity of the light emitting part.

2. The organic electroluminescence element according to claim 1, wherein the electrostatic capacity of the rectifier part is equal to or smaller than a half of the electrostatic capacity of the light emitting part.

3. The organic electroluminescence element according to claim 1, wherein the rectifier part is formed over the light emitting part.

4. The organic electroluminescence element according to claim 3, wherein the rectifier part is formed over part of the light emitting part.

5. The organic electroluminescence element according to claim 4, wherein the rectifier part is located between the light emitting part and a light emitting surface of the organic electroluminescence element so that a light emitted from the light emitting part reaches the rectifier part before reaching the light emitting surface of the organic electroluminescence element.

6. The organic electroluminescence element according to claim 5, wherein the rectifier part transmits the light emitted from the light emitting part.

7. The organic electroluminescence element according to claim 3, wherein the light emitting part includes a first electrode, a hole transport layer formed on the first electrode, a light emitting layer formed on the hole transport layer, an electron injection layer formed on the light emitting layer and a second electrode formed on the electron injection layer, and the rectifier part includes the second electrode of the light emitting part as its lower electrode, an organic layer formed on the lower electrode, and an upper electrode formed on the organic layer.

8. The organic electroluminescence element according to claim 1, wherein the light emitting part includes a transparent electrode, a hole transport layer formed on the transparent electrode, a light emitting layer formed on the hole transport layer, an electron injection layer formed on the light emitting layer, and a metal electrode formed on the electron injection layer.

9. The organic electroluminescence element according to claim 1, wherein the rectifier part includes a first metal electrode, an organic layer formed on the first metal electrode, and a second metal electrode formed on the organic layer.

10. A method of fabricating an organic electroluminescence element comprising the steps of:

forming first and second electrodes independently;

forming an organic thin layer diode on the first electrode;

forming a lead electrode over the whole of the organic thin layer diode and over at least part of the second electrode; and

forming an organic electroluminescence body over the second electrode and lead electrode, the organic electroluminescence body having a layer structure and including at least one organic electroluminescence light emitting layer.

11. The method according to claim 10, wherein an electrostatic capacity of the organic thin layer diode is smaller than an electrostatic capacity of the organic electroluminescence body.

12. The method according to claim 11, wherein the electrostatic capacity of the organic thin layer diode is equal to or smaller than half of the electrostatic capacity of the organic electroluminescence body.

13. The method according to claim 10, wherein the organic thin layer diode and lead electrode can transmit a light.