Organic light emitting devices

• US 6,030,700 A
• Filed: 11/07/1997
• Issued: 02/29/2000
• Est. Priority Date: 12/13/1994
• Status: Expired due to Term

• Current Assignee: The Trustees of Princeton University (Princeton University)
• Original Assignee: The Trustees of Princeton University (Princeton University)
• Inventors: Burrows, Paul Edward, Sapochak, Linda Susan, McCarty, Dennis Matthew, Forrest, Stephen Ross, Thompson, Mark Edward
• Primary Examiner(s): Nakarani, D. S.
• Application Number:
  US08/966,485
• Time in Patent Office: 844 Days
• Field of Search: 257/89, 257/90, 257/94, 257/96, 257/97, 257/98, 257/440, 257/443, 428/336, 428/432, 428/433, 428/434, 428/457, 427/77, 427/78
• US Class Current: 428/336
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: H01L 24/82 by forming build-up interconnects at chip-level, e.g. for high density interconnects [HDI] interconnection structure between a plurality of semiconductor chips H01L23/5389
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/12033 Gunn diode
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H10K 2102/3031 Two-side emission, e.g. transparent OLEDs [TOLED]
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/14 Carrier transporting layers
• CPC Class Codes: H10K 50/828 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 59/32 Stacked devices having two or more layers, each emitting at different wavelengths
• CPC Class Codes: H10K 85/10 Organic polymers or oligomers
• CPC Class Codes: H10K 85/111 comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
• CPC Class Codes: H10K 85/113 Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
• CPC Class Codes: H10K 85/114 Poly-phenylenevinylene; Derivatives thereof
• CPC Class Codes: H10K 85/146 poly N-vinylcarbazol; Derivatives thereof
• CPC Class Codes: H10K 85/30 Coordination compounds
• CPC Class Codes: H10K 85/322 : comprising boron
• CPC Class Codes: H10K 85/324 : comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/341 : Transition metal complexes, e.g. Ru(II)polypyridine complexes H10K85/331 takes precedence
• CPC Class Codes: H10K 85/60 : Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence
• CPC Class Codes: H10K 85/611 : Charge transfer complexes
• CPC Class Codes: H10K 85/631 : Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: Y10T 428/26 : Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/265 : 1 mil or less
• CPC Class Codes: Y10T 428/31678 : Of metal

Abstract

A multicolor organic light emitting device employs vertically stacked layers of double heterostructure devices which are fabricated from organic compounds. The vertical stacked structure is formed on a glass base having a transparent coating of ITO or similar metal to provide a substrate. Deposited on the substrate is the vertical stacked arrangement of three double heterostructure devices, each fabricated from a suitable organic material. Stacking is implemented such that the double heterostructure with the longest wavelength is on the top of the stack. This constitutes the device emitting red light on the top with the device having the shortest wavelength, namely, the device emitting blue light, on the bottom of the stack. Located between the red and blue device structures is the green device structure. The devices are configured as stacked to provide a staircase profile whereby each device is separated from the other by a thin transparent conductive contact layer to enable light emanating from each of the devices to pass through the semitransparent contacts and through the lower device structures while further enabling each of the devices to receive a selective bias.

Claims

1. An organic light emitting device structure, comprising:

a substrate;

a first electrically conductive material formed over the substrate;

a first organic layer comprising a first organic emissive structure formed over the first electrically conductive material;

a second electrically conductive material formed over the first organic emissive structure;

a second organic layer comprising a second organic emissive structure formed over the second electrically conductive material; and

a third electrically conductive material formed over the second organic emissive structure;

wherein the organic emissive structures are transparent and the first and second organic emissive structures independently emit light when energized.

2. The organic light emitting device structure of claim 1, further comprising

a third organic layer comprising a third organic emissive structure formed over the third electrically conductive material;

and

a fourth electrically conductive material formed over the third organic emissive structure;

wherein the third organic emissive structure emits light when energized.

3. The organic light emitting device structure of claim 1 or 2, wherein each of said organic emissive structures emits a different wavelength of light.

4. The organic light emitting device structure of claim 1 or 2, wherein at least one of said organic emissive structures is a single heterostructure or a double heterostructure.

5. The organic light emitting device structure of claim 1 or 2, wherein each of said organic emissive structures is a single heterostructure or a double heterostructure.

6. The organic light emitting device structure of claim 1 or 2, wherein at least one of the electrically conductive materials comprises an indium tin oxide layer and a metal layer.

7. The organic light emitting device structure of claim 6, wherein said metal layer has a work function of less than four electron volts.

8. The organic light emitting device structure of claim 1 or 2, wherein at least one of the electrically conductive materials comprises a metal layer of about 100 Angstroms thick or less.

9. The organic light emitting device structure of claim 1 or 2, wherein at least one of said organic emissive structures is vapor deposited.

10. The organic light emitting device structure of claim 1 or 2, wherein each of said organic emissive structures is vapor deposited.

11. The organic light emitting device structure of claim 1 or 2, wherein light is emitted from the substrate side of said device.

12. The organic light emitting device structure of claim 1 or 2, wherein light is emitted from the side of said device opposite the substrate.

13. The organic light emitting device structure of claim 12, further comprising a reflective layer disposed between said organic emissive structure closest to said substrate and said substrate.

14. The organic light emitting device structure of claim 12, further comprising a layer of anti-reflecting material adjacent said organic emissive structure farthest from said substrate.

15. An organic light emitting device structure, comprising:

a substrate;

a first electrically conductive material formed over the substrate;

first and second organic layers comprising first and second organic emissive structures, respectively, stacked one over the other, to form a layered structure over the substrate;

at least one electrically conductive material being disposed between the first and second organic emissive structures; and

at least one electrically conductive material over the stack of said organic emissive structures;

wherein the organic light emitting device structure is transparent; and

wherein the first and second organic emissive structures independently emit light when energized.

16. The organic light emitting device structure of claim 15, wherein a third organic layer comprising a third organic emissive structure is stacked over said second organic emissive structure, and an electrically conductive material is disposed between said second and third organic emissive structures;

and

wherein when energized the third organic emissive structure emits light independently of the first and second organic emissive structures.

17. A transparent organic light emitting device comprising:

a substrate;

a first electrically conductive material over the substrate;

a first organic layer comprising a first organic emissive structure formed over the first electrically conductive material;

a second electrically conductive material over the first organic emissive structure;

wherein at least one of said first and second electrically conductive materials (a) comprises a metal layer having a thickness less than about 100 Angstroms and (b) physically contacts said organic emissive structure.

21. The transparent organic light emitting device of claim 17, 18 or 19, wherein said at least one of said electrodes further comprises an indium tin oxide layer.

22. The transparent organic light emitting device of claim 17, 18, 19 or 20, wherein said metal layer is made of a metal having a work function that is less than about 4 electron volts.

23. The transparent organic light emitting device of claim 17, 18, 19 or 20, wherein said metal layer is magnesium/silver alloy.

24. The transparent organic light emitting device of claim 17, 18, 19 or 20, wherein said metal layer is about 50 Angstroms thick or less.

25. The transparent organic light emitting device of claim 17, 18, 19 or 20, further comprising a second organic layer comprising a second organic emissive structure over said second electrically conductive material and a third electrically conductive material over said second organic emissive structure.

18. A transparent organic light emitting device comprising:

a substrate;

a first electrically conductive material over the substrate;

a first organic layer comprising a first organic emissive structure formed over the electrically conductive material; and

a second electrically conductive material over the first organic emissive structure;

wherein at least one of said first and second electrically conductive materials comprises a metal layer having a thickness less than about 100 Angstroms; and

wherein each layer between said first and second electrically conductive materials is a charge carrying material.

19. A transparent organic light emitting device comprising:

a substrate;

a first electrically conductive material over the substrate;

a first organic layer comprising a first organic emissive structure formed over the electrically conductive material; and

a second electrically conductive material over the first organic emissive structure;

wherein at least one of said first and second electrically conductive materials comprises a metal layer having a thickness of about 50 Angstroms or less.

20. A transparent organic light emitting device comprising:

a substrate;

a first electrically conductive material over the substrate;

a first organic layer comprising a first organic emissive structure formed over the electrically conductive material; and

a second electrically conductive material over the first organic emissive structure;

wherein at least one of said first and second electrically conductive materials comprises an indium tin oxide layer and a metal layer.