Submount based surface mount device (SMD) light emitter components and methods

• US 9,780,268 B2
• Filed: 01/31/2013
• Issued: 10/03/2017
• Est. Priority Date: 04/04/2006
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Hussell, Christopher P., Welch, Erin, Reiherzer, Jesse Colin, Andrews, Peter Scott
• Primary Examiner(s): SANDVIK, BENJAMIN P
• Application Number:
  US13/755,993
• Publication Number:
  US 20130193468A1
• Time in Patent Office: 1,706 Days
• 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 planar surface area;

at least first and second electrical contacts disposed on the first side of the submount, wherein a combined surface area of the at least first and second electrical contacts comprises an electrical contact area;

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

an optical element disposed over the at least one light emitter chip, wherein the optical element comprises a first portion that is at an acute angle with respect to the planar surface area of the submount and wherein the at least first and second electrical contacts are positioned below the first portion of the optical element;

wherein the electrical contact area is less than half of the planar surface area of the first side of the submount; and

wherein the submount comprises a central axis that divides the submount into a first sectional portion and a second sectional portion, the electrical contact area being fully disposed on either the first sectional portion or the second sectional portion.

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

3. The component of claim 1, wherein the at least first and second electrical contacts are different sizes and different shapes.

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

5. The component of claim 3, further comprising an electrostatic discharge (ESD) protection device disposed over a surface of the first or the second electrical contact.

6. The component of claim 1, wherein the optical element extends to each edge 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 a submount thickness and the dome height is approximately 1.

12. The component of claim 1, wherein the optical element comprises an encapsulant, at least a portion of the encapsulant being disposed on the first side of the submount.

13. The component of claim 1, wherein the optical element comprises a substantially curved apex.

14. The component of claim 1, wherein the planar surface area comprises approximately 9 square millimeters (mm²) or less.

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

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

17. The component of claim 1, wherein the electrical contact 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 submount is a highly reflective alumina submount, to which the at least one light emitter chip is directly mounted.

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 Watts per meter-Kelvin (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 at least first and second electrical contacts are positioned away from the at least one light emitter chip by at least approximately 100 micrometers (μ

m) or more.

26. A light emitter component comprising:

a ceramic based submount comprising a first surface and having a first thickness, a maximum submount width, and a maximum submount length that is substantially equal to the maximum submount width;

at least one light emitter chip disposed on the first surface of the submount; and

an optical element disposed over the submount, the optical element having a second thickness and comprising a low profile lens in a shape of a non-hemispheric dome having a maximum lens width and a maximum lens length that is substantially equal to the maximum lens width, wherein;

a base of the dome contacts the submount at each outermost edge of the submount,

the base of the dome is non-circular,

the maximum lens length and maximum lens width, as measured at the base of the dome, are substantially equal to the maximum submount length and maximum submount width, respectively, and

the second thickness is a maximum height of the dome, as measured from the first surface of the submount,

wherein a ratio between the first thickness and the second thickness is approximately equal to 1, and

wherein a ratio between the maximum lens height and the maximum lens width of the dome is less than 0.5.

27. The component of claim 26, further comprising first and second electrical contacts disposed on the submount, wherein the first and second electrical contacts comprise a different size and a different shape.

28. The component of claim 26, further comprising a first electrical contact and a second electrical contact that are disposed along a same edge of the submount and on a same side of the at least one light emitter chip.

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 each outermost edge of the submount.

32. The component of claim 26, further comprising an electrostatic discharge (ESD) protection device disposed on the first surface of the submount.

33. The component of claim 29, wherein a portion of each 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 an encapsulant, at least a portion of the encapsulant being disposed on a same side of the submount to which the at least one light emitter chip is mounted.

35. The component of claim 26, wherein the optical element comprises a sectional profile, a first portion of a sectional profile being substantially curved and a second portion of the sectional profile being substantially straight and acutely angled with respect to the first surface of the submount.

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

37. The component of claim 26, further comprising a plurality of light emitter chips on the 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, wherein the first and second electrical contacts are positioned away from the at least one light emitter chip by at least approximately 100 μ

m or more.

42. A light emitter component comprising:

a submount comprising a first surface and having a maximum submount width and a maximum submount length that is substantially equal to the maximum submount width;

at least one light emitter chip disposed on the first surface of the submount; and

a lens having an apex and a maximum lens height, as measured from the first surface of the submount, the lens comprising a non-circular lens base, which has a base width,

wherein the base width of the non-circular lens base is substantially equal to the maximum submount length and the maximum submount width,

wherein the apex is centrally disposed over the at least one light emitter chip and the lens has a profile without any points of inflection from the apex to an outer edge of the submount, and

wherein a ratio between the maximum lens height and the base width is less than 0.5.

43. The component of claim 42, wherein the ratio of the maximum lens height and the base width is less than approximately 0.4.

44. The component of claim 42, wherein the ratio of the maximum lens height and the base width is less than approximately 0.3.

45. The component of claim 42, wherein the ratio of the maximum lens height and the base width is less than approximately 0.2.

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

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

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

49. The component of claim 42, further comprising a plurality of light emitter chips on the submount.

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

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

52. The component of claim 42, wherein the at least one light emitter chip comprises at least one 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/mK.

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, wherein the first and second electrical contacts are positioned away from the at least one light emitter chip by at least approximately 100 μ

m or more.