UV light emitting diode package and light emitting diode module having the same

• US 10,580,929 B2
• Filed: 03/24/2017
• Issued: 03/03/2020
• Est. Priority Date: 03/30/2016
• Status: Active Grant

• Current Assignee: Seoul Viosys Co., Ltd. (Seoul Semiconductor Co., Ltd.)
• Original Assignee: Seoul Viosys Co., Ltd. (Seoul Semiconductor Co., Ltd.)
• Inventors: Won Cheol, Seo
• Primary Examiner(s): Withers, Grant S
• Application Number:
  US15/469,443
• Publication Number:
  US 20170288088A1
• Time in Patent Office: 1,075 Days
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 2933/0075 relating to heat extraction or cooling elements
• 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 33/0025 comprising only AIIIBV compounds
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/465 with a resonant cavity structure
• CPC Class Codes: H01L 33/486 : adapted for surface mounting
• CPC Class Codes: H01L 33/507 : the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/58 : Optical field-shaping elements
• 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
• CPC Class Codes: H01L 33/641 : characterized by the materials
• CPC Class Codes: H01L 33/642 : characterized by the shape

Abstract

A UV LED package and an LED module including the same. The UV LED package includes an upper semiconductor layer; a mesa disposed under the upper semiconductor layer, having an inclined side surface, and comprising an active layer and a lower semiconductor layer; a first insulation layer covering the mesa and having an opening exposing the upper semiconductor layer; a first contact layer contacting the upper semiconductor layer through the opening of the first insulation layer; a second contact layer formed between the mesa and the first insulation layer and contacting the lower semiconductor layer; a first electrode pad and a second electrode pad disposed under the first contact layer and electrically connected to the first contact layer and second contact layer, respectively; and a second insulation layer located between the first contact layer and the first and second electrode pads, wherein the active layer emits UV light having a wavelength of 405 nm or less. With this structure, the LED package has high efficiency and high heat dissipation characteristics.

Claims

1. An ultraviolet light emitting diode (UV LED) package comprising:

an upper semiconductor layer;

a mesa disposed under the upper semiconductor layer, having an inclined side surface, and comprising an active layer and a lower semiconductor layer, the mesa including portions protruding from the upper semiconductor layer along a first direction perpendicular to a top surface of the upper semiconductor layer and separated by a region;

a first insulation layer covering the mesa and having an opening exposing the upper semiconductor layer and structured to include an opening;

a first contact layer contacting the upper semiconductor layer through the opening of the first insulation layer and including a first portion disposed on the first insulation layer to contact with the first insulation layer and fill a part of the region and a second portion disposed under a second contact layer;

the second contact layer formed between the mesa and the first insulation layer and contacting the lower semiconductor layer;

a first electrode pad and a second electrode pad disposed under the first contact layer and electrically connected to the first contact layer and second contact layer, respectively; and

a second insulation layer located between the first contact layer and the first and second electrode pads and including a portion filled in a remaining part of the region, wherein the active layer emits UV light having a wavelength of 405 nm or less;

an interconnection layer disposed to contact with the second contact layer through the opening of the first insulation layer and disposed at a same level as the second portion of the first contact layer; and

wherein the first insulation layer and the second insulation layer are in contact with the upper semiconductor layer, and

wherein the first portion of the first contact layer is disposed between the first insulation layer and the portion of the second insulation layer along a second direction perpendicular to the first direction.

2. The UV LED package of claim 1, wherein the upper semiconductor layer comprises a greater concentration of Al than a well layer of the active layer to allow light having a wavelength 10 nm or more shorter than peak wavelengths of light emitted from the active layer to pass therethrough.

3. The UV LED package of claim 2, wherein the active layer emits UV light having a wavelength of 365 nm or less.

4. The UV LED package of claim 1, further comprising:

a growth substrate located on the first conductive type upper semiconductor layer.

5. The UV LED package of claim 4, wherein the growth substrate has a thickness of 150 μ

m or more.

6. The UV LED package of claim 5, wherein the growth substrate has a thickness of 300 μ

m or more.

7. The UV LED package of claim 5, wherein the growth substrate has a roughened surface on an upper surface thereof.

8. The UV LED package of claim 4, wherein the upper semiconductor layer has unevenness on an upper surface thereof.

9. The UV LED package of claim 4, wherein the upper semiconductor layer comprises an AlN layer having a thickness of 2 μ

m or more.

10. The UV LED package of claim 9, wherein the upper semiconductor layer further comprises a superlattice layer between the AlN layer and the active layer.

11. The UV LED package of claim 1, wherein the lower semiconductor layer comprises a layer having a greater Ga concentration or a smaller Al concentration than a well layer of the active layer in order to absorb light emitted from the active layer.

12. The UV LED package of claim 1, wherein the first insulation layer is a reflector formed by stacking insulation layers having different indices of refraction.

13. The UV LED package of claim 1, wherein the first contact layer comprises a reflective metal layer.

14. The UV LED package of claim 13, wherein the first contact layer contacts the upper semiconductor layer between the mesa and an edge of the upper semiconductor layer along a periphery of the mesa.

15. The UV LED package of claim 14, wherein the first contact layer further contacts the upper semiconductor layer through bays or through-holes formed in the mesa.

16. An ultraviolet light emitting diode (UV LED) module comprising

a circuit board having first and second pads;

and

an UV LED package mounted on the circuit board, wherein the UV package comprises;

an upper semiconductor layer;

a mesa disposed under the upper semiconductor layer, having an inclined side surface, and comprising an active layer and a lower semiconductor layer, the mesa including portions protruding from the upper semiconductor layer along a first direction perpendicular to a top surface of the upper semiconductor layer and separated by a region;

a first insulation layer covering the mesa and having an opening exposing the upper semiconductor layer and structured to include an opening;

a first contact layer contacting the upper semiconductor layer through the opening of the first insulation layer and including a first portion disposed on the first insulation layer to contact with the first insulation layer and fill a part of the region and fill a part of the region and a second portion disposed over a second contact layer;

the second contact layer formed between the mesa and the first insulation layer and contacting the lower semiconductor layer;

a first electrode pad and a second electrode pad disposed under the first contact layer and electrically connected to the first contact layer and second contact layer, respectively; and

a second insulation layer located between the first contact layer and the first and the second electrode pads and including a portion filled in a remaining part of the region;

an interconnection layer disposed to contact with the second contact layer through the opening of the first insulation layer and disposed at a same level as the second portion of the first contact layer; and

wherein the first electrode pad and the second electrode pad of the UV LED package are electrically connected to the first pad and the second pad, respectively, and

wherein the first insulation layer and the second insulation layer are in contact with the upper semiconductor layer, and

wherein the first portion of the first contact layer is disposed between the first insulation layer and the portion of the second insulation layer along a second direction perpendicular to the first direction.

17. The UV LED module of claim 16, wherein the circuit board is a ceramic printed circuit board having a metal interconnection line embedded therein.

18. The UV LED module of claim 16, further comprising:

a first metal bump between the first pad and the first electrode pad; and

a second metal bump between the second pad and the second electrode pad.

19. The UV LED module of claim 18, wherein each of the first and second metal bumps has a single layer or a multilayer structure formed of a material selected from the group consisting of Sn, AuSn, Au, and NiSn.

20. The UV LED module of claim 16, further comprising:

a light guide part covering the UV LED package.

21. A light emitting diode (LED) package comprising:

a semiconductor stack including a first conductive type semiconductor layer and a mesa structure located between a first sidewall and a second sidewall of the mesa structure and including portions protruding from the first conductive type semiconductor layer along a first direction perpendicular to a top surface of the first conductive type semiconductor layer and including corresponding portions of a second conductive type semiconductor layer and an active layer interposed between the first and second conductive type semiconductor layers, wherein the first and second sidewalls of the mesa structure are outermost sidewalls of the mesa structure and the mesa structure is structured to expose the first conductive type semiconductor layer on an exterior contact region of the semiconductor stack located on a periphery of the mesa structure and to expose the first conductive type semiconductor layer on an interior contact region located between the portions of mesa structure;

a first electrical contact disposed to contact the first conductive type semiconductor layer on the exterior contact region of the semiconductor stack and to provide a first electrical contact path to the semiconductor stack, the first electrical contact including a first portion disposed to contact the first conductive type semiconductor layer at the interior contact region and a second portion disposed over a second electrical contact;

the second electrical contact disposed to contact the second conductive type semiconductor layer and to provide a second electrical contact path to the semiconductor stack;

an inner insulation layer formed on the exterior contact region of the semiconductor stack to cover the first and second sidewalls to protect the semiconductor stack from an external environment, the inner insulation layer disposed to cover the mesa and in contact with the first electrical contact at the interior contact region and structured to include an opening;

an outer insulation layer formed to cover a side surface of the inner insulation layer and including a portion disposed between portions of the mesa structure to contact the portion of the first electrical contact; and

an interconnection layer disposed to contact with the second electrical contact layer through the opening of the inner insulation layer and disposed at a same level as the second portion of the first electrical contact, and

wherein the inner insulation layer, the first electrical contact, and the outer insulation layer are located in the exterior contact region.

22. The LED package of claim 21, wherein the external sidewall of the semiconductor stack is inclined.

23. The LED package of claim 21, wherein the first electrical contact is disposed between the inner insulation layer and the outer insulation layer.

24. The LED package of claim 21, wherein the inner insulation layer includes a single layer including silicon oxide or silicon nitride.

25. The LED package of claim 21, wherein the inner insulation layer includes an optically reflective structure.

26. The LED package of claim 21, wherein the inner insulation layer includes a distributed Bragg reflector.

27. The LED package of claim 21, wherein the inner insulation layer includes layers of silicon oxide or silicon nitride.

28. The LED package of claim 21, wherein the inner insulation layer includes a silicon oxide layer and a distributed Bragg reflector.

29. The LED package of claim 21, wherein the inner insulation layer extends to cover the second electrical contact to protect the second electrical contact from an external environment.

30. The LED package of claim 21, wherein the outer insulation layer includes a single layer including silicon dioxide or silicon nitride.

31. The LED package of claim 21, wherein the outer insulation layer includes multiple layers.

32. The LED package of claim 21, wherein the outer insulation layer includes an optically reflective structure.

33. The LED package of claim 21, wherein the outer insulation layer includes a distributed Bragg reflector.

34. The LED package of claim 21, wherein the outer insulation layer extends to cover the first electrical contact and the second electrical contact to protect the first electrical contact and the second electrical contact from the external environment.

35. The LED package of claim 34, wherein the outer insulation layer includes phosphor materials.

36. The LED package of claim 35, wherein the first electrical contact and the second electrical contact are arranged on a first surface of the semiconductor stack and the outer insulation layer further extends to cover a second surface of the semiconductor stack opposite to the first surface.

37. The LED package of claim 21, further including:

a first bump electrically coupled to the first conductive type semiconductor layer by the first electrical contact;

a second bump electrically coupled to the second conductive type semiconductor layer by the second electrical contact; and

an additional insulation layer formed over the inner insulation layer and the outer insulation layer to cover side surfaces of the first and second bumps to protect the first and second bumps from an external environment.

38. The LED package of claim 37, wherein the additional insulation layer includes a polymer.

39. The LED package of claim 21, wherein the second conductive type semiconductor layer has a thickness smaller than that of the first conductive type semiconductor layer.

40. The LED package of claim 21, wherein the first conductive type semiconductor layer has a roughened surface.

41. A light emitting diode (LED) package comprising:

a semiconductor stack including a first conductive type semiconductor layer having a first surface and a second surface opposite to the first surface and a mesa structure including portions protruding from the first conductive type semiconductor layer along a first direction perpendicular to a top surface of the first conductive type semiconductor layer and including corresponding portions of an active layer formed on the first surface of the first conductive type semiconductor layer and a second conductive type semiconductor layer formed on the active layer, wherein the first conductive type semiconductor layer is disposed on a periphery of the mesa structure to provide an exterior contact region in which the first conductive type semiconductor layer is exposed by the active layer and the second conductive type semiconductor layer and the first conductive type semiconductor layer is structured to expose the first conductive type semiconductor layer on an interior contact region located between the portions of mesa structure;

a first insulation layer formed on a side of the semiconductor stack to cover a side surface of the semiconductor stack, the first insulation layer structured to include an opening;

a second insulation layer formed on the side of the semiconductor stack to cover a side surface of the first insulation layer, the second insulation layer covering the side surface of the semiconductor stack and including a portion disposed between the portions of the mesa structure; and

a third insulation layer formed on the side of the semiconductor stack to cover a side surface of the second insulation layer, the third insulation layer covering the side surface of the semiconductor stack,

a first electrical contact path disposed closer to the first surface of the first conductive type semiconductor layer than the second surface of the first conductive type semiconductor layer and electrically contacting with the first conductive type semiconductor layer, the first electrical contact path including a first portion disposed at the interior contact region to contact with the first insulation layer and the portion of the second insulation layer and a second portion disposed under the second conductive type semiconductor layer;

a second electrical contact path disposed closer to the first surface of the first conductive type semiconductor layer than the second surface of the first conductive type semiconductor layer and electrically contacting with the second conductive type semiconductor layer; and

an interconnection layer disposed to contact with the second electrical contact path through the opening of the first insulation layer and disposed at a same level as the second portion of the first electrical contact path, and

wherein the first insulation layer, the second insulation layer, and the third insulation layer are located in the exterior contact region.

42. The LED package of claim 41, wherein the side surface of the semiconductor stack is inclined.

43. The LED package of claim 41, wherein the first electrical contact path is provided between the first insulation layer and the second insulation layer.

44. The LED package of claim 41, wherein the first electrical contact path is provided on the sides of the semiconductor stack.

45. The LED package of claim 41, wherein the first insulation layer and the second insulation layer include a transparent insulation layer.

46. The LED package of claim 45, further comprising an optically reflective structure between the first and second insulation layers.

47. The LED package of claim 41, wherein the first insulation layer includes a transparent insulation layer and the second insulation layer includes an optically reflective structure.

48. The LED package of claim 47, wherein the optically reflective structure includes a distributed Bragg reflector.

49. The LED package of claim 47, wherein the optically reflective structure includes a distributed Bragg reflector reflecting light having wavelength corresponding to one of blue light, green light, or red light.

50. The LED package of claim 41, wherein the third insulation layer extends to cover the first electrical contact path and the second electrical contact path to protect the first electrical contact path and the second electrical contact path from the external environment.

51. The LED package of claim 41, wherein the third insulation layer includes phosphor material.

52. The LED package of claim 41, wherein the third insulation layer is free of phosphors.

53. The LED package of claim 52, further comprising an additional insulation layer formed on the side of the semiconductor stack to cover a side surface of the third insulation layer, the additional layer covering the side surface of the semiconductor stack.

54. The LED package of claim 53, wherein the additional insulation layer includes phosphor material.

55. The LED package of claim 41, further including a wavelength convertor arranged on the second surface of the first conductive type semiconductor layer and including phosphor material.

56. The LED package of claim 41, wherein the second conductive type semiconductor layer has a thickness smaller than that of the first conductive type semiconductor layer.

57. The LED package of claim 41, wherein the first surface of the first conductive type semiconductor layer has a roughness.