SOLID STATE LIGHTING COMPONENT PACKAGE WITH LAYER

• US 20140021493A1
• Filed: 07/20/2012
• Published: 01/23/2014
• Est. Priority Date: 07/20/2012
• Status: Active Grant

• Current Assignee: CREE Led Incorporated (Smart Global Holdings Incorporated)
• Original Assignee: Joseph Clark, Peter Andrews
• Inventors: SUNDANI, HARSH, ANDREWS, PETER, CLARK, JOSEPH
• Granted Patent: US 9,287,475 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• 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 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A solid state lighting component comprising a layer having high reflectivity and/or scattering properties, the layer positioned about a solid state lighting component, and manufacturing methods of making same is disclosed. A method of increasing the luminous flux of the solid state lighting component, is also provided.

Claims

1. A solid state lighting component comprising:

a substrate having a top surface, the top surface of the substrate comprising

a first region comprising a die pad;

a second region comprising a light absorbing feature, the second region spaced apart from the first region by a portion of the top surface of the substrate; and

a layer positioned within the first region, the layer at least partially surrounding the die pad, and the layer positioned within the second region at least partially covering the light absorbing feature, the layer comprising a material configured for scattering and/or reflecting emitted light.

2. The solid state lighting component of claim 1, further comprising an LED element, wherein the material is present in an amount sufficient to reflect and/or scatter light emitted from the LED element, reduce absorption of the emitted light, and combinations thereof.

3. The solid state lighting component of claim 1, wherein the light absorbing feature is one or more of a wire trace, a wire bond, an Electrostatic Discharge Device (ESD), a solder mask, exposed surfaces of the substrate, and a heteroepitaxial layer on the substrate.

4. The solid state lighting component of claim 3, wherein the die pad is completely surrounded by the layer and the light absorbing feature is completely covered by the layer.

5. The solid state lighting component of claim 1, wherein the layer is arranged substantially polygonally and/or substantially annularly about the die pad.

6. The solid state lighting component of claim 2, wherein the LED element has side walls projecting from the substrate, the sidewalls supporting a top surface of the LED element, the top surface having a height from the substrate;

and the layer having at least a portion thereof with a height less than, equal to, or greater than the height of the top surface of the LED element.

7. The solid state lighting component of claim 2, further comprising an optical media having an exterior and an interior positioned about the LED element on the substrate.

8. The solid state lighting component of claim 7, wherein the layer at least partially surrounds the exterior of optical media adjacent the substrate.

9. The solid state lighting component of claim 7, wherein the interior of the optical media at least partially surrounds the layer.

10. The solid state lighting component of claim 1, wherein the second region is positioned within the first region.

11. The solid state lighting component of claim 2, wherein the LED element is part of an array of LED elements, the layer at least partially surrounding one or more individual LED elements of the array of LED elements and/or the array of LED elements.

12. The solid state lighting component of claim 1, wherein the layer has a first index of refraction between about 1.4 and about 1.5, and the material has a second index of refraction between about 1.8 to about 2.4.

13. The solid state lighting component of claim 1, wherein the layer comprises titanium dioxide and polydimethylsiloxane, polyphenylsiloxane, or blends thereof.

14. The solid state lighting component of claim 1, wherein the top surface of the substrate comprises aluminum nitride and the feature comprises one or more electrostatic discharge devices (ESD'"'"'s).

15. The solid state lighting component of claim 1, further comprising a light absorbing material.

16. The solid state lighting component of claim 15, wherein the layer comprises the light absorbing material.

17. The solid state lighting component of claim 15, wherein the light absorbing material is dispersed, distributed, or combined with a second layer comprising a polymer matrix.

18. The solid state lighting component of claim 17, wherein the second layer is positioned in the first region and/or the second region, or is positioned exclusive of the first region and the second region.

19. A method of manufacturing a solid state lighting component comprising:

providing a solid state lighting component substrate with a top surface, the top surface having a first region comprising at least one die pad and a second region comprising at least one light absorbing feature, the second region spaced apart from the first region;

introducing a layer to the first region and the second region, the layer comprising a light reflecting and/or light scattering material, the layer at least partially surrounding the die pad and at least partially covering the light absorbing feature.

20. The method of claim 19, wherein the light absorbing feature is one or more of a wire trace, a wire bond, an Electrostatic Discharge Device (ESD), a solder mask, exposed surfaces of the substrate, and a heteroepitaxial layer on the substrate.

21. The method of claim 19, further comprising a step of shaping the layer, optionally, curing the layer during or after the shaping step.

22. The method of claim 19, wherein the second region is positioned within the first region.

23. The method of claim 19, wherein the shape of the layer is substantially annular or substantially polygonal.

24. The method of claim 19, wherein the top surface of the substrate comprises an LED element having side walls projecting from the substrate, the sidewalls supporting a top surface of the LED element, the top surface having a height from the substrate;

wherein at least a portion of the layer has an average height less than, equal to, or greater than the height of the top surface of the LED element.

25. The method of claim 24, further comprising the step of introducing an optical media about the LED element.

26. The method of claim 25, wherein the optical media is at least partially surrounded by the layer.

27. The method of claim 25, wherein the layer is at least partially surrounded by the optical media.

28. The method of claim 25, wherein the step of introducing the optical media about the LED element is performed after the step of introducing the layer.

29. The method of claim 19, wherein the layer comprises a matrix having a first index of refraction between about 1.4 and about 1.5 and the light reflecting/light scattering material has a second index of refraction between about 1.8 and about 2.4.

30. The method of claim 19, wherein the light reflecting/light scattering material comprises titanium dioxide and the matrix comprises at least one of polydimethylsiloxane and polyphenylsiloxane.

31. The method of claim 19, further comprising a light absorbing material.

32. The method of claim 31, wherein the layer comprises the light absorbing material.

33. The method of claim 31, wherein the light absorbing material is dispersed, distributed, or combined with a second layer comprising a polymer matrix.

34. The method of claim 33, wherein the second layer is positioned in the first region and/or the second region, or is positioned exclusive of the first region and the second region.

35. The method of claim 33, further comprising introducing an optical element to the substrate about one or more of the die pads, optional comprising one or more LED elements, wherein the optical media is a lens with an interior surface and an exterior surface and wherein the optical element is positioned on the substrate with the second layer contacting one or both of the interior surface or the exterior surface of the optical element.

36. A method of increasing the luminous flux of a solid state lighting component, the method comprising:

providing a solid state lighting component substrate with a top surface, the top surface having a first region comprising at least one die pad and LED element, and a second region spaced apart from the first region on the top surface, the second region comprising at least one light absorbing feature;

introducing a layer to the top surface of the substrate, the layer comprising a material configured to reflect and/or scatter light emitted by an LED element, the layer at least partially surrounding the die pad and at least partially covering the light absorbing feature; and

increasing the luminous flux of the solid state lighting component by scattering and/or reflecting light emitted by the LED element and/or reducing the amount of emitted light absorbed by the light absorbing feature.

37. The method of claim 36, further comprising reducing absorption of the emitted light.

38. The method of claim 36, wherein the light absorbing feature is one or more of a wire trace, a wire bond, an Electrostatic Discharge Device (ESD), a solder mask, exposed surfaces of the substrate, and a heteroepitaxial layer on the surface.

39. The method of claim 36, wherein the step of introducing the layer surrounds the die pad and completely covers the feature.

40. The method of claim 36, wherein the step of introducing the layer provides a portion of the top surface of the substrate without the layer.

41. The method of claim 36, wherein the second region is introduced within the first region.

42. The method of claim 36, wherein the layer has an average height from the top surface of the substrate that is about equal to or greater than the maximum vertical height of the LED element.

43. The method of claim 36, wherein the introducing step provides the layer as substantially annular or substantially polygonal.

44. The method of claim 36, wherein the layer is introduced prior to mounting the LED element on the die pad.

45. The method of claim 36, wherein the layer is introduced after mounting the LED element on the mount.

46. The method of claim 36, wherein the LED element is part of an array of LED elements.

47. The method of claim 46, wherein the layer at least partially surrounds the array of LED elements and/or at least partially surrounds one or more individual LED elements of the array.

48. The method of claim 36, wherein the layer comprises a matrix material having a first index of refraction between about 1.4 and about 1.5 and the material having a second index of refraction between about 1.8 and about 2.4.

49. The method of claim 36, wherein the layer comprises titanium dioxide and at least one of polydimethylsiloxane and polyphenylsiloxane.

50. The method of claim 36, further comprising introducing an optical element to the substrate about one or more of the LED elements.

51. The method of claim 50, wherein the optical element is a lens with an interior surface and an exterior surface and wherein the optical element is positioned on the substrate with the layer contacting one or both of the interior surface or the exterior surface of the optical element.

52. The method of claim 50, further comprising a light absorbing material.

53. The method of claim 52 wherein the layer comprises the light absorbing material.

54. The method of claim 52, wherein the light absorbing material is dispersed, distributed, or combined with a second layer comprising a polymer matrix.

55. The method of claim 54, wherein the second layer is positioned in the first region and/or the second region, or is positioned exclusive of the first region and the second region.

56. The method of claim 54, further comprising introducing an optical element to the substrate about one or more of the LED elements wherein the optical media is a lens with an interior surface and an exterior surface and wherein the optical element is positioned on the substrate with the second layer contacting one or both of the interior surface or the exterior surface of the optical element.

57. A solid state lighting component comprising

an array of LED elements;

and

a reflecting dam configured for scattering and/or reflecting emitted light from one or more of the LED elements, the reflecting dam having a three dimensional structure at least partially surrounding one or more individual LED element of the array of LED elements, or the array of LED elements.

58. The solid state lighting component of claim 57, wherein the reflecting dam surrounds one or more individual LED elements of the array of LED elements along one or more sides of the individual LED element.

59. The solid state lighting component of claim 57, wherein the reflecting dam surrounds the array of LED elements.

60. The solid state lighting component of claim 57, wherein the reflecting dam surrounds one or more LED element of the array of LED elements and surrounds the array of LED elements.

61. The solid state lighting component of claim 57, wherein the reflecting dam surrounds each LED element of the array of LED elements and surrounds the array of LED elements.

62. The solid state lighting component of claim 57, wherein the three dimensional structure of the reflective dam is discontinuous.

63. The solid state lighting component of claim 57, wherein the array of LED elements comprises a first set of one or more LED elements emitting light of a first color, and a second set of one or more LED elements emitting light of a second color.

64. The solid state lighting component of claim 57, wherein the reflective dam reduces absorption of the emitted light from one or more LED elements by a light absorbing feature.

65. The solid state lighting component of claim 57, wherein the reflective dam comprises titanium dioxide and polydimethylsiloxane, polyphenylsiloxane, or blends thereof.