SUBMOUNT BASED SURFACE MOUNT DEVICE (SMD) LIGHT EMITTER COMPONENTS AND METHODS

• US 20130193468A1
• Filed: 01/31/2013
• Published: 08/01/2013
• Est. Priority Date: 04/04/2006
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Hussell, Christopher P., Reiherzer, Jesse Colin, Andrews, Peter Scott, Welch, Erin
• Granted Patent: US 9,780,268 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• 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 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

Submount based surface mount design (SMD) light emitter components and related methods are disclosed. In some aspects, light emitter components can include a submount with a first side having a first surface area, first and second electrical contacts disposed on the first side of the submount, and at least one light emitter chip on the first side. In some aspects, the electrical contact area can be less than half of the first surface area of the first side of the submount. Components disclosed herein can include low profile parts or domes where a ratio between a dome height and a dome width is less than 0.5. A method of providing components can include providing a panel of material and LED chips, dispensing a liquid encapsulant material over the panel, and singulating the panel into individual submount based components after the encapsulant material has hardened.

Claims

1. A light emitter component comprising:

a submount comprising a first side having a first surface area, the first surface area comprising an electrical contact area;

at least first and second electrical contacts disposed on the first side of the submount, wherein the first and second electrical contacts form at least a portion or all of the electrical contact area;

at least one light emitter chip on the first side of the submount and electrically connected to the first and second electrical contacts; and

wherein the electrical contact area is less than half of the first surface area of the first side of the submount.

2. The component of claim 1, wherein the submount comprises a ceramic material.

3. The component of claim 1, wherein the first and second electrical contacts are disposed along a same edge of the submount.

4. The component of claim 1, further comprising at least two vias disposed in a portion of the submount.

5. The component of claim 1, further comprising an optical element.

6. The component of claim 5, wherein the optical element extends to the edges of the first side of the submount.

7. The component of claim 6, wherein the optical element comprises silicone.

8. The component of claim 6, wherein the optical element comprises a phosphor material.

9. The component of claim 6, wherein the optical element comprises a dome.

10. The component of claim 9, wherein a ratio between a dome height and a dome width is less than approximately 0.5.

11. The component of claim 9, wherein a ratio between the submount thickness and the dome height is approximately 1.

12. The component of claim 5, wherein the optical element comprises encapsulant, and at least a portion of the encapsulant is disposed on the first side of the submount.

13. The component of claim 5, wherein the optical element comprises a profile, where a first portion of the profile is substantially curved and a second portion of the profile is substantially straight.

14. The component of claim 1, wherein the first surface area comprises approximately 9 mm² or more.

15. The component of claim 1, wherein the second surface area is less than approximately 4.5 mm².

16. The component of claim 1, wherein the second surface area is less than approximately 3.6 mm².

17. The component of claim 1, wherein the second surface area is less than approximately 2.7 mm².

18. The component of claim 1, wherein the light emitter component is devoid of a cavity.

19. The component of claim 1, further comprising a meniscus forming feature disposed proximate an edge of the submount.

20. The component of claim 1, wherein the light emitter chip is directly mounted to a highly reflective alumina submount.

21. The component of claim 1, further comprising a low profile dome disposed over the submount.

22. The component of claim 1, wherein the submount has a thermal conductivity of greater than 5 W/mK, greater than 10 W/mK, greater than 50 W/mK, greater than 100 W/mK, greater than 150 W/mK, or greater than 200 W/mK.

23. The component of claim 1, wherein the submount has a thermal conductivity of approximately 20 W/mK.

24. The component of claim 1, wherein the submount has a thermal conductivity of approximately 170 W/mK.

25. The component of claim 1, wherein the first and second electrical contacts are positioned away from the light emitter chip by at least approximately 100 μ

m or more.

26. A light emitter component comprising:

a ceramic based submount of a first thickness;

at least one light emitter chip on the submount;

an optical element of a second thickness; and

wherein a ratio between the first thickness and the second thickness is greater than approximately 0.5.

27. The component of claim 26, wherein the ratio between the first thickness and the second thickness is approximately 1.

28. The component of claim 26, further comprising a first contact and a second electrical contact that are disposed along a same edge of the submount.

29. The component of claim 26, further comprising at least two vias disposed in a portion of the submount.

30. The component of claim 26, wherein the submount comprises alumina.

31. The component of claim 26, wherein the optical element extends to the edges of the submount.

32. The component of claim 26, further comprising an electrostatic discharge (ESD) protection device.

33. The component of claim 26, wherein a portion of the at least two vias is disposed along an external surface of the submount.

34. The component of claim 26, wherein the optical element comprises encapsulant, and wherein at least a portion of the encapsulant is disposed on a same side of the submount to which an LED chip is mounted.

35. The component of claim 26, wherein the optical element comprises a profile, where a first portion of the profile is substantially curved and a second portion of the profile is substantially straight.

36. The component of claim 26, wherein the light emitter chip is directly mounted to a highly reflective alumina submount.

37. The component of claim 26, further comprising a low profile dome disposed over submount.

38. The component of claim 26, wherein the submount has a thermal conductivity of greater than 5 W/mK, greater than 10 W/mK, greater than 50 W/mK, greater than 100 W/mK, greater than 150 W/mK, or greater than 200 W/mK.

39. The component of claim 26, wherein the submount has a thermal conductivity of approximately 20 W/mK.

40. The component of claim 26, wherein the submount has a thermal conductivity of approximately 170 W/mK.

41. The component of claim 26, further comprising first and second electrical contacts disposed on the submount, and wherein the first and second electrical contacts are positioned away from the light emitter chip by at least approximately 100 μ

m or more.

42. A light emitter component comprising:

a submount;

at least one light emitter chip on the submount;

a dome comprising a dome height and a dome width; and

wherein a ratio between the dome height and the dome width is less than approximately 0.5.

44. The component of claim 42, wherein the ratio of the dome height to the dome width is less than approximately 0.3.

45. The component of claim 42, wherein the ratio of the dome height to the dome width is less than approximately 0.2.

46. The component of claim 42, wherein the dome comprises silicone.

47. The component of claim 42, wherein the submount comprises ceramic.

48. The component of claim 42, wherein the light emitter chip is directly mounted to a highly reflective alumina submount.

49. The component of claim 42, wherein the dome comprises a low profile dome directly disposed over submount.

50. The component of claim 42, wherein the dome comprises encapsulant, and wherein at least a portion of the encapsulant is disposed on a same side of the submount to which the light emitter chip is mounted.

51. The component of claim 42, wherein the optical element comprises a profile, where a first portion of the profile is substantially curved and a second portion of the profile is substantially straight.

52. The component of claim 42, wherein the light emitter chip comprises a light emitting diode (LED).

53. The component of claim 42, further comprising a via.

54. The component of claim 53, wherein the via is at least partially disposed along an external surface of the submount.

55. The component of claim 53, wherein the via is only disposed internally within a portion of the submount.

56. The component of claim 42, wherein the submount has a thermal conductivity of greater than 5 W/mK, greater than 10 W/mK, greater than 50 W/mK, greater than 100 W/mK, greater than 150 W/mK, or greater than 200 W/m K.

57. The component of claim 42, wherein the submount has a thermal conductivity of approximately 20 W/mK.

58. The component of claim 42, wherein the submount has a thermal conductivity of approximately 170 W/mK.

59. The component of claim 42, further comprising first and second electrical contacts disposed on the submount, and wherein the first and second electrical contacts are positioned away from the light emitter chip by at least approximately 100 μ

m or more.

43. The component of claim 43, wherein the ratio of the dome height to the dome width is less than approximately 0.4.

60. A method of providing submount based light emitter components, the method comprising:

providing a panel of material;

forming a plurality of vias within the panel of material;

forming one or more traces on the panel of material;

attaching a plurality of light emitting diode (LED) chips over a first surface of the panel;

dispensing a liquid encapsulant material over the first surface of the panel; and

singulating the panel into individual submount based components.

61. The method of claim 60, wherein providing the panel comprises providing a panel of alumina.

62. The method of claim 60, further comprising scribing the panel prior to dispensing encapsulant material over the first surface.

63. The method of claim 60, wherein the LED chips are directly attached to the panel of material via silicone.

64. The method of claim 60, further comprising providing a meniscus forming feature over opposing edges of the submount.

65. The method of claim 60, further comprising curing the liquid encapsulant material.

66. The method of claim 60, further comprising wirebonding the LED chips to electrical contacts.

67. The method of claim 60, wherein the wirebond loops at least substantially downward between the LED chips and electrical contacts.

68. The method of claim 60, further comprising depositing electrical contacts over the panel of material.

69. The method of claim 60, wherein at least a portion of the liquid encapsulant is applied to the first surface.

70. The method of claim 60, wherein the cured encapsulant comprises a profile, where a first portion of the profile is substantially curved and a second portion of the profile is substantially straight.

71. The method of claim 60, wherein the panel is provided with a thermal conductivity of greater than 5 W/mK, greater than 10 W/mK, greater than 50 W/mK, greater than 100 W/mK, greater than 150 W/mK, or greater than 200 W/mK.

72. The method of claim 60, wherein the panel is provided with a thermal conductivity of approximately 20 W/mK.

73. The method of claim 60, wherein the panel is provided with a thermal conductivity of approximately 170 W/mK.

74. The method of claim 60, wherein the one or more traces are positioned away from a light emitter chip on each panel by at least approximately 100 μ

m or more.