High reliability, high efficiency, integratable organic light emitting devices and methods of producing same

• US 6,046,543 A
• Filed: 12/23/1996
• Issued: 04/04/2000
• Est. Priority Date: 12/23/1996
• Status: Expired due to Term

• Current Assignee: Princeton University, The Trustees of Princeton University (Princeton University)
• Original Assignee: The Trustees of Princeton University (Princeton University)
• Inventors: Forrest, Stephen R., Bulovic, Vladimir, Burrows, Paul, Garbuzov, Dmitri Z.
• Primary Examiner(s): OEN, WILLIAM L
• Application Number:
  US08/774,119
• Time in Patent Office: 1,198 Days
• Field of Search: 313/504, 313/506, 313/507, 313/509, 313/499, 428/421, 428/690, 428/691
• US Class Current: 313/504
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 2102/321 Inverted OLED, i.e. having cathode between substrate and anode
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/17 Carrier injection layers
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 50/805 Electrodes
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/813 characterised by their shape
• CPC Class Codes: H10K 50/822 characterised by their shape
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 50/856 comprising reflective means
• CPC Class Codes: H10K 50/86 Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 59/32 Stacked devices having two or more layers, each emitting at different wavelengths
• CPC Class Codes: H10K 59/80515 characterised by their shape
• CPC Class Codes: H10K 59/80521 characterised by their shape
• CPC Class Codes: H10K 59/873 Encapsulations
• CPC Class Codes: H10K 59/876 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/878 : comprising reflective means
• CPC Class Codes: H10K 59/8791 : Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 85/324 : comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/621 : Aromatic anhydride or imide compounds, e.g. perylene tetra-carboxylic dianhydride or perylene tetracarboxylic di-imide

Abstract

An organic light emitting device (OLED) having an inverted structure including a cathode layer which is deposited on a substrate and on top of which an electron transporting layer (ETL), an electroluminescent (EL) layer, a hole transporting layer (HTL), a protection layer and an anode are deposited in sequence. The inverted OLED (IOLED) provides improved longevity, flexibility and efficiency over conventional OLEDs.

Claims

1. An organic light emitting device comprising:

a substrate;

a cathode layer formed on a top surface of the substrate;

a first organic layer formed on the cathode layer;

a second organic layer formed on the first organic layer;

a protection layer formed on the second organic layer; and

an anode layer formed on the protection layer,

wherein at least one of the first and second organic layers emits a first light upon application of a voltage between the anode layer and the cathode layer.

2. The light emitting device of claim 1, wherein:

the first organic layer is comprised of an electroluminescent sublayer and an electron supporting sublayer,

the second organic layer is a hole transporting layer, and

the first organic layer emits the first light upon application of the voltage between the anode layer and the cathode layer.

3. The light emitting device of claim 1, wherein:

the first organic layer is an electron transporting layer,

the second organic layer is an electroluminescent sublayer and a hole transporting sublayer, and

the second organic layer emits the first light upon application of the voltage between the anode layer and the cathode layer.

4. The light emitting device of claim 1, wherein:

the first organic layer is comprised of an electroluminescent sublayer and an electron transporting sublayer, the electroluminescent sublayer being arranged between the electron transporting sublayer and the second organic layer,

the second organic layer is a hole transporting layer, and

the electroluminescent sublayer emits the first light upon application of the voltage between the anode layer and the cathode layer.

5. The light emitting device of claim 1, further including a smoothing layer between the top surface of the substrate and the cathode layer.

6. The light emitting device of claim 1, further comprising:

a second cathode layer formed over the anode layer;

a third organic layer formed on the second cathode layer;

a fourth organic layer formed on the third organic layer;

a second protection layer formed on the fourth organic layer; and

a second anode layer formed on the second protection layer,

wherein at least one of the third and fourth organic layers emits a second light upon application of a voltage between the second anode layer and the second cathode layer.

7. The light emitting device of claim 6, further comprising:

a third cathode layer formed over the second anode layer;

a fifth organic layer formed on the third cathode layer;

a sixth organic layer formed on the fifth organic layer;

a third protection layer formed on the sixth organic layer; and

a third anode layer formed on the third protection layer,

wherein at least one of the fifth and sixth organic layers emits a third light upon application of a voltage between the second anode layer and the second cathode layer.

8. The light emitting device of claim 7, wherein the first, second and third lights are selected from the group consisting of red, green and blue light.

9. The light emitting device of claim 1, further comprising a filter structure including two layers of dielectric material.

10. The light emitting device of claim 9, wherein the light emitting device is arranged over the filter structure.

11. A display including a plurality of light emitting devices in accordance with claim 1.