Light-radiating semiconductor component with a luminescence conversion element

• US 7,629,621 B2
• Filed: 07/26/2007
• Issued: 12/08/2009
• Est. Priority Date: 06/26/1996
• Status: Expired due to Fees

• Current Assignee: OSRAM Licht AG (Ams-Osram AG)
• Original Assignee: OSRAM GmbH (Ams-Osram AG)
• Inventors: Schlotter, Peter, Schmidt, Ralf, Schneider, Jurgen, Reeh, Ulrike, Stath, Norbert, Waitl, Gunter, Hohn, Klaus
• Primary Examiner(s): Jackson, Jr.; Jerome
• Application Number:
  US11/828,450
• Publication Number:
  US 20080149958A1
• Time in Patent Office: 866 Days
• Field of Search: 257/98
• US Class Current: 257/98
• CPC Class Codes: C09K 11/7718 with alkaline earth metals
• CPC Class Codes: C09K 11/7746 with alkaline earth metals
• CPC Class Codes: C09K 11/7767 Chalcogenides
• CPC Class Codes: C09K 11/7769 Oxides C09K11/7768 takes precedence
• CPC Class Codes: C09K 11/7774 Aluminates
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/32257 the layer connector connecting to a bonding area disposed in a recess of the surface of the item
• CPC Class Codes: H01L 2224/48091 Arched
• 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 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• 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 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01021 Scandium [Sc]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12044 : OLED
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2933/0091 : Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/486 : adapted for surface mounting
• CPC Class Codes: H01L 33/50 : Wavelength conversion elements
• CPC Class Codes: H01L 33/501 : characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: Y02B 20/00 : Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

The light-radiating semiconductor component has a radiation-emitting semiconductor body and a luminescence conversion element. The semiconductor body emits radiation in the ultraviolet, blue and/or green spectral region and the luminescence conversion element converts a portion of the radiation into radiation of a longer wavelength. This makes it possible to produce light-emitting diodes which radiate polychromatic light, in particular white light, with only a single light-emitting semiconductor body. A particularly preferred luminescence conversion dye is YAG:Ce.

Claims

1. A light-radiating semiconductor component, comprising:

a semiconductor body comprising a layer sequence configured to emit light in a first wavelength range comprising one or more of ultraviolet, blue, and green; and

a luminescence conversion element applied directly to said semiconductor body, the luminescence conversion element comprising at least one luminescent material configured to convert some of the light emitted from the semiconductor body to a different color in a second wavelength range,

the luminescence conversion element is configured such that during operation of the light-radiating semiconductor component, the converted light combines with the remaining light emitted from the semiconductor body to produce a light output for the light-radiating semiconductor component having a mixture of colors comprising a perceptible amount of light in the first wavelength range and a perceptible amount of light in the second wavelength range.

2. The component of claim 1, wherein the luminescence conversion element is a luminescence conversion encapsulation applied directly to the semiconductor body, and wherein the luminescent material is dispersed within the luminescence conversion encapsulation.

3. The component of claim 1, wherein the luminescence conversion element is a luminescence conversion layer applied directly to the semiconductor body, and wherein the luminescent material is dispersed within the luminescence conversion layer.

4. The component of claim 1, wherein said second wavelength range includes wavelengths at least some of which are longer than wavelengths of the first wavelength range.

5. The component of claim 1, wherein the colors in the first wavelength range and the second wavelength range lie at least partially in mutually complementary-color spectral regions, such that white light is radiated by the component during operation thereof.

6. The component of claim 1, wherein the luminescent material is further configured to convert some of the light emitted from the semiconductor body to a third color in a third wavelength range, and wherein the colors in the first, second, and third wavelength ranges form an additive color triad, such that white light is radiated by the component during operation thereof.

7. The component of claim 1, wherein the light emitted by said semiconductor body has a luminescence intensity maximum in a blue spectral region at a wavelength between 420 nm and 460 nm.

8. The component of claim 1, wherein said luminescence conversion element comprises organic dye molecules in a plastic matrix.

9. The component of claim 1, wherein said luminescence conversion material comprises at least one inorganic luminescence material selected from the phosphor group.

10. The component of claim 1, wherein said luminescence conversion element further comprises light-diffusing particles.

11. The component of claim 1, wherein at least about 20% of the polychromatic light emitted from the component comprises light in the first wavelength range produced by the layer sequence.

27. The component of claim 1, further comprising a housing having a recess, wherein the semiconductor body is positioned in the recess.

29. Apparatus comprising a display device and one or more light-radiating semiconductor components as claimed in claim 1 disposed to illuminate the display device.

32. The apparatus of claim 29, wherein the display device is a liquid crystal display device.

35. The apparatus of claim 1, wherein the light output having a mixture of colors comprises a spectra with at least one local peak in intensity corresponding to the emission from the layer sequence in the semiconductor body.

36. The apparatus of claim 35, wherein the local peak in intensity is in a blue spectral region.

37. The apparatus of claim 36, wherein the local peak in intensity is at a wavelength between 420 nm and 460 nm.

38. The apparatus of claim 36, wherein the local peak in intensity is at a wavelength of approximately 430 nm.

39. The apparatus of claim 36, wherein the local peak in intensity is at a wavelength of approximately 470 nm.

40. The apparatus of claim 1, wherein at least about 20% of the output light having the mixture of colors comprises light in the first wavelength range produced by the layer sequence.

41. The apparatus of claim 1, wherein at least about 30% of the output light having the mixture of colors comprises light in the first wavelength range produced by the layer sequence.

42. The apparatus of claim 1, wherein at least about 50% of the output light having the mixture of colors comprises light in the first wavelength range produced by the layer sequence.

43. The apparatus of claim 1, wherein the luminescence conversion material in the luminescence conversion element excludes materials whose emission is peaked in a blue spectral region.

44. The apparatus of claim 1, wherein the second wavelength range consists of radiation having one or more local emission peaks in the green, yellow, and red spectral regions, but not the blue spectral region.

12. A light-radiating semiconductor component, comprising:

a semiconductor body comprising a layer sequence configured to emit light in a first wavelength range comprising one or more of ultraviolet, blue, and green, wherein during operation the semiconductor body emits the light with greater intensity along a first direction than along other directions; and

a luminescence conversion element comprising a luminescent material configured to convert some of the light emitted from the semiconductor body to a different color in a second wavelength range and scatter at least some of the unconverted light along the other directions,

the luminescence conversion element is configured such that during operation the light-radiating semiconductor component emits light with a mixture of colors comprising perceptible amounts of the converted light and perceptible amounts of the unconverted light.

13. The component of claim 12, wherein the scattering by the luminescent material causes the light emitted from the light-radiating component in the first and second wavelength ranges to be substantially homogeneous along different emission directions.

14. The component of claim 12, wherein the luminescent conversion material comprises luminescent powder and the luminescent conversion element comprises a matrix comprising a distribution of the luminescent powder.

15. The component of claim 12, wherein the luminescent conversion material comprises luminescent powder and the luminescent conversion element comprises a matrix comprising a distribution of the luminescent powder, and wherein the scattering by the luminescent powder causes the light emitted from the light-radiating component in the first and second wavelength ranges to be substantially homogeneous along different emission directions.

16. The component of claim 12, wherein the luminescence conversion element is applied directly to the semiconductor body.

17. The component of claim 15, wherein the luminescence conversion element is applied directly to the semiconductor body.

18. The component of claim 16, wherein the luminescence conversion element is a luminescence conversion encapsulation applied directly to the semiconductor body, and wherein the luminescent material is dispersed within the luminescence conversion encapsulation.

19. The component of claim 16, wherein the luminescence conversion element is a luminescence conversion layer applied directly to the semiconductor body, and wherein the luminescent material is dispersed within the luminescence conversion layer.

20. The component of claim 12, wherein said second wavelength range includes wavelengths at least some of which are longer than wavelengths of the first wavelength range.

21. The component of claim 12, wherein the colors in the first wavelength range and the second wavelength range lie at least partially in mutually complementary-color spectral regions, such that white light is radiated by the component during operation thereof.

22. The component of claim 15, wherein the colors in the first wavelength range and the second wavelength range lie at least partially in mutually complementary-color spectral regions, such that white light is radiated by the component during operation thereof.

23. The component of claim 12, wherein the luminescent material is further configured to convert some of the light emitted from the semiconductor body to a third color in a third wavelength range, and wherein the colors in the first, second, and third wavelength ranges form an additive color triad, such that white light is radiated by the component during operation thereof.

24. The component of claim 15, wherein the luminescent material is further configured to convert some of the light emitted from the semiconductor body to a third color in a third wavelength range, and wherein the colors in the first, second, and third wavelength ranges form an additive color triad, such that white light is radiated by the component during operation thereof.

25. The component of claim 12, wherein the light emitted by said semiconductor body has a luminescence intensity maximum in a blue spectral region at a wavelength between 420 nm and 460 nm.

26. The component of claim 12, wherein said luminescence conversion material comprises at least one inorganic luminescence material selected from the phosphor group.

28. The component of claim 12, further comprising a housing having a recess, wherein the semiconductor body is positioned in the recess.

30. Apparatus comprising a display device and one or more light-radiating semiconductor components as claimed in claim 12 disposed to illuminate the display device.

31. Apparatus comprising a display device and one or more light-radiating semiconductor components as claimed in claim 15 disposed to illuminate the display device.

33. The apparatus of claim 30, wherein the display device is a liquid crystal display device.

34. The apparatus of claim 31, wherein the display device is a liquid crystal display device.

45. The apparatus of claim 12, wherein the light output having a mixture of colors comprises a spectra with at least one local peak in intensity corresponding to the emission from the layer sequence in the semiconductor body.

46. The apparatus of claim 45, wherein the local peak in intensity is in a blue spectral region.

47. The apparatus of claim 46, wherein the local peak in intensity is at a wavelength between 420 nm and 460 nm.

48. The apparatus of claim 46, wherein the local peak in intensity is at a wavelength of approximately 430 nm.

49. The apparatus of claim 46, wherein the local peak in intensity is at a wavelength of approximately 470 nm.

50. The apparatus of claim 12, wherein at least about 20% of the output light having the mixture of colors comprises light in the first wavelength range produced by the layer sequence.

51. The apparatus of claim 12, wherein at least about 30% of the output light having the mixture of colors comprises light in the first wavelength range produced by the layer sequence.

52. The apparatus of claim 12, wherein at least about 50% of the output light having the mixture of colors comprises light in the first wavelength range produced by the layer sequence.

53. The apparatus of claim 12, wherein the luminescence conversion material in the luminescence conversion element excludes materials whose emission is peaked in a blue spectral region.

54. The apparatus of claim 12, wherein the second wavelength range consists of radiation having one or more local emission peaks in the green, yellow, and red spectral regions, but not the blue spectral region.