Hybrid light-emitting sources for efficient and cost effective white lighting and for full-color applications

• US 5,966,393 A
• Filed: 02/04/1997
• Issued: 10/12/1999
• Est. Priority Date: 12/13/1996
• Status: Expired due to Term

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: DenBaars, Steven P., Heeger, Alan J., Hide, Fumitomo
• Primary Examiner(s): DAVIE, JAMES W
• Application Number:
  US08/795,190
• Time in Patent Office: 980 Days
• Field of Search: 372/21, 372/53, 372/54, 372/39, 372/7, 372/23, 372/75
• US Class Current: 372/23
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01S 3/0933 of a semiconductor, e.g. light emitting diode
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 85/111 comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
• CPC Class Codes: H10K 85/114 Poly-phenylenevinylene; Derivatives thereof
• CPC Class Codes: H10K 85/115 Polyfluorene; Derivatives thereof

Abstract

Hybrid inorganic light emitting device/luminescent polymer light-emitting sources for efficient and cost effective white lighting and for full-color applications and their manufacture are disclosed. The hybrid light sources include an inorganic light-emitting source such as a p-n junction diode-containing device capable of emitting a first emitted output of light and a photoluminescent polymer element positioned in the first emitted output of light, the polymer being selected to be capable of being pumped by a first portion of the first emitted output of light and when so pumped of emitting a second emitted output of light which is emitted from the device with that portion of the first emitted output remaining beyond the first portion.

Claims

1. A hybrid solid state light-emitting device comprising

an electrically-powered, solid state, inorganic, light emitter capable of emitting a first emitted output of light

and

a photoluminescent polymer element positioned in the first emitted output of light, the polymer element comprising a photoluminescent conjugated semiconducting polymer which is pumped by a first portion of the first emitted output of light and when so pumped emits a second emitted output of light which is emitted from the device with that portion of the first emitted output if any remaining beyond the first portion.

2. The hybrid solid state light-emitting device of claim 1 wherein the electrically-powered, solid state, inorganic, light emitter is selected from the group consisting of a p-n junction diode-containing light emitter, a p-i-n junction triode-containing light emitter, a p-n junction laser diode light emitter, a metal-insulator-semiconductor (M-I-S)-containing light emitter, and a semiconductor quantum cascade pump source light emitter.

3. The hybrid solid state light-emitting device of claim 2 wherein the electrically-powered, solid state, inorganic, light emitter is a p-n junction light emitting diode.

4. The hybrid solid state light-emitting device of claim 3 wherein the p-n junction light emitting diode is a Group III-nitride p-n junction light-emitting diode.

5. The hybrid solid state light-emitting device of claim 2 wherein the electrically-powered, solid state, inorganic, light emitter is a p-i-n junction triode-containing light emitter.

6. The hybrid solid state light-emitting device of claim 5 wherein the electrically-powered, solid state, inorganic, light emitter is a p-i-n junction light emitting triode.

7. The hybrid solid state light-emitting device of claim 6 wherein the p-i-n junction light emitting triode is a Group III-nitride p-n junction light-emitting triode.

8. The hybrid solid state light-emitting device of claim 2 wherein the electrically-powered, solid state, inorganic, light emitter is a p-n junction laser diode light emitter.

9. The hybrid solid state light-emitting device of claim 8 wherein the p-n junction laser diode is a Group III-nitride p-n junction laser diode.

10. The hybrid solid state light-emitting device of claim 2 wherein the electrically-powered, solid state, inorganic, light emitter is a metal-insulator-semiconductor (M-I-S)-containing light emitter.

11. The hybrid solid state light-emitting device of claim 2 wherein the electrically-powered, solid state, inorganic, light emitter is a semiconductor quantum cascade pump source light emitter.

12. The hybrid solid state light-emitting device of claim 4 wherein the Group III-nitride p-n junction light-emitting diode comprises a (In,Ga)N alloy system.

13. The hybrid solid state light-emitting device of claim 4 wherein the Group III-nitride p-n junction diode comprises group III-nitride grown by metal organic chemical vapor deposition (MOCVD).

14. The hybrid solid state light-emitting device of claim 3 wherein the p-n junction diode-containing device is a SiC or II-VI compound semiconductor-containing p-n junction light-emitting diode.

15. The hybrid solid state light-emitting device of claim 14 wherein the II-VI compound semiconductor is ZnSe.

16. The hybrid solid state light-emitting device of claim 1 wherein the photoluminescent polymer element is a thin film through which that portion of the first emitted output remaining beyond the first portion passes.

17. The hybrid solid state light-emitting device of claim 1 wherein the photoluminescent polymer element is a polymer body through which that portion of the first emitted output remaining beyond the first portion passes.

18. The hybrid solid state light-emitting device of claim 1 wherein the photoluminescent polymer element is a polymer body into which the first portion of the first emitted output is absorbed.

19. The hybrid solid state light-emitting device of claim 1 wherein the first emitted output of light and the second emitted output of light have different wavelengths.

20. The hybrid solid state light-emitting device of claim 19 wherein the wavelengths of the first emitted output of light and the second emitted output of light are selected to produce a white light for the combined emission.

21. The hybrid solid state light-emitting device of claim 1 wherein the conjugated semiconducting polymer has a band gap of from about 1 to about 3 eV.

22. The hybrid solid state light-emitting device of claim 21 wherein the conjugated semiconducting polymer has a photoluminescence quantum efficiency greater than 10%.

23. The hybrid solid state light-emitting device of claim 21 wherein the conjugated semiconducting polymer has a photoluminescence quantum efficiency greater than 50%.

24. The hybrid solid state light-emitting device of claim 1 wherein the photoluminescent polymer element additionally comprises light scattering particles in admixture with the photoluminescent conjugated semiconducting polymer.

25. The hybrid solid state light-emitting device of claim 21 wherein the conjugated semiconducting polymer is selected from the group of a conjugated semiconducting polymer with the poly(phenylenevinylene) backbone molecular structure, a conjugated semiconducting polymer with the poly(phenylenevinylene) backbone molecular structure and functionalized with side chains to make it soluble in common organic solvents, a conjugated semiconducting polymer with the poly(phenylene) backbone molecular structure, a conjugated semiconducting polymer with the poly(phenylene) molecular structure and functionalized with side chains to make it soluble in common organic solvents, a conjugated semiconducting polymer with the poly(fluorene) backbone molecular structure, and a conjugated semiconducting polymer with the poly(fluorene) backbone molecular structure and functionalized with side chains to make it soluble in common organic solvents.

27. The hybrid solid state light-emitting device of claim 1 wherein the first emitted output of light is blue-green or blue light.

28. The hybrid solid state light-emitting device of claim 1 additionally comprising a lens positioned in the first emitted output of light.

29. The hybrid solid state light-emitting device of claim 28 wherein the photoluminescent polymer element is attached to the lens.

30. The hybrid solid state light-emitting device of claim 29 wherein the photoluminescent polymer element is a coating attached to the lens.

31. The hybrid solid state light-emitting device of claim 30 wherein the lens has an inner surface adjacent to the p-n junction diode device and an exterior surface and wherein the coating is on the exterior surface.

32. The hybrid solid state light-emitting device of claim 31 additionally comprising a hardcoat upon the coating of photoluminescent polymer.

33. The hybrid solid state light-emitting device of claim 1 wherein the photoluminescent polymer element is the gain medium in a resonant structure and the p-n junction diode device and the photoluminescent polymer are selected so that the p-n junction diode device'"'"'s first emitted output of light pumps the photoluminescent polymer element above its threshold for lasing.

34. The hybrid solid state light-emitting device of claim 33 wherein the resonant structure is a planar waveguide.

35. The hybrid solid state light-emitting device of claim 33 wherein the planar waveguide has distributed feedback.

36. The hybrid solid state light-emitting device of claim 33 wherein the resonant structure is a channel waveguide.

37. The hybrid solid state light-emitting device of claim 33 wherein the channel waveguide has distributed feedback.

38. The hybrid solid state light-emitting device of claim 33 wherein the resonant structure is a microcavity.

26. A hybrid solid state light-emitting device comprising

an electrically-powered, solid state, inorganic, light emitter capable of emitting a first emitted output of light

and

a photoluminescent polymer element positioned in the first emitted output of light, the polymer element comprising a saturated polymer mixed with luminescent dyes or a saturated polymer having a saturated main chain with luminescent dye molecules attached to the main chain via side-chains which is pumped by a first portion of the first emitted output of light and when so pumped emits a second emitted output of light which is emitted from the device with that portion of the first emitted output remaining beyond the first portion.