Multicolor organic electroluminescent device formed of vertically stacked light emitting devices

• US 7,714,504 B2
• Filed: 02/02/2007
• Issued: 05/11/2010
• Est. Priority Date: 12/13/1994
• Status: Expired due to Fees

• Current Assignee: The Trustees of Princeton University (Princeton University)
• Original Assignee: The Trustees of Princeton University (Princeton University)
• Inventors: McCarty, Dennis Matthew, Burrows, Paul E., Forrest, Stephen R., Thompson, Mark E., Sapochak, Linda Susan
• Primary Examiner(s): Santiago; Mariceli
• Application Number:
  US11/701,743
• Publication Number:
  US 20070132369A1
• Time in Patent Office: 1,194 Days
• Field of Search: 313498-512
• US Class Current: 313/504
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: G09F 9/335 being organic light emitting diodes [OLED]
• CPC Class Codes: H01L 2224/24145 the bodies being stacked
• 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 2924/01021 Scandium [Sc]
• CPC Class Codes: H01L 2924/01068 Erbium [Er]
• CPC Class Codes: H01L 2924/12041 LED
• 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 50/8423 Metallic sealing arrangements
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/844 Encapsulations
• 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

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. The devices are substantially transparent when de-energized, making them useful for heads-up display applications.

Claims

1. An energizable, light emitting structure, comprising:

a substrate;

a first layer of transparent, electrically conductive material supported on said substrate;

a first transparent, energizable, light emitting device (LED1) supported on said first layer of transparent, electrically conductive material, said LED1 including an emission layer of organic material and said LED1 being operative to produce light when energized;

a second layer of transparent electrically conductive material supported by said LED1, said second layer of electrically conductive material being substantially transparent;

a second transparent, energizable, light emitting device (LED2) supported on said second layer of transparent electrically conductive material said LED2 including an emission layer of organic material, and said LED2 being operative to produce light when energized; and

a third layer of transparent electrically conductive material supported by said LED2.

2. The energizable, light emitting structure of claim 1, wherein the substrate is a transparent substrate.

3. The energizable, light emitting structure of claim 1, wherein the substrate is a rigid substrate.

4. The energizable, light emitting structure of claim 1, wherein the second transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a transparent electrically conductive oxide layer.

5. The energizable, light emitting structure of claim 1, wherein the second transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a work function less than 4 eV and a transparent electrically conductive oxide layer.

6. The energizable, light emitting structure of claim 1, which further comprises:

a third transparent, energizable, light emitting device (LED3) supported on said third layer of transparent electrically conductive material, said LED3 including an emission layer of organic material and said LED3 being operative to produce light when energized; and

a fourth layer of electrically conductive material supported by said LED3.

7. The energizable, light emitting structure of claim 6, wherein the third transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a transparent electrically conductive oxide layer.

8. The energizable, light emitting structure of claim 6, wherein the third transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a work function less than 4 eV and a transparent electrically conductive oxide layer.

9. The energizable, light emitting structure of claim 6, wherein the fourth transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a transparent electrically conductive oxide layer.

10. The energizable, light emitting structure of claim 6, wherein the fourth transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a work function less than 4 eV and a transparent electrically conductive oxide layer.

11. A multicolor light emitting device structure comprising

a substrate;

a first transparent electrically conductive layer formed over the substrate;

a first organic light emitting device formed over the first transparent electrically conductive layer;

a second transparent electrically conductive layer formed over the first organic light emitting device;

a second organic light emitting device formed over the second transparent electrically conductive layer;

a third transparent electrically conductive layer formed over the second organic light emitting device;

wherein said first and second organic light emitting devices each comprise an organic emission layer for emitting light of a desired color, respectively.

12. The multicolor light emitting device structure of claim 11, wherein the substrate is a transparent substrate.

13. The multicolor light emitting device structure of claim 11, wherein the substrate is a rigid substrate.

14. The multicolor light emitting device structure of claim 11, wherein the second transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a transparent electrically conductive oxide layer.

15. The multicolor light emitting device structure of claim 11, wherein the second transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a work function less than 4 eV and a transparent electrically conductive oxide layer.

16. The multicolor light emitting device structure of claim 11, which further comprises:

a third organic light emitting device formed over the third transparent electrically conductive layer, wherein the third organic light emitting device comprises an organic emission layer for emitting light of a desired color; and

a fourth transparent electrically conductive layer formed over the third organic light emitting device.

17. The multicolor light emitting device structure of claim 16, wherein the third transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a transparent electrically conductive oxide layer.

18. The multicolor light emitting device structure of claim 16, wherein the third transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a work function less than 4 eV and a transparent electrically conductive oxide layer.

19. The multicolor light emitting device structure of claim 16, wherein the fourth transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a transparent electrically conductive oxide layer.

20. The multicolor light emitting device structure of claim 16, wherein the fourth transparent electrically conductive layer comprises a transparent electrically conductive metal layer having a work function less than 4 eV and a transparent electrically conductive oxide layer.

21. The multicolor light emitting device structure of claim 17, wherein the fourth transparent electrically conductive layer comprises a second transparent electrically conductive metal layer having a thickness less than about 100 angstroms and a second transparent electrically conductive oxide layer.

22. The multicolor light emitting device structure of claim 18, wherein the fourth transparent electrically conductive layer comprises a second transparent electrically conductive metal layer having a work function less than 4 eV and a second transparent electrically conductive oxide layer.