LIGHT EMITTING DEVICE AND METHOD FOR MANUFACTURING THE SAME

• US 20140124812A1
• Filed: 05/15/2012
• Published: 05/08/2014
• Est. Priority Date: 05/16/2011
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Kuramoto, Masafumi, Tsuruha, Tomoaki, Hayashi, Masaki, Iwakura, Daisuke, Ozeki, Kenji, Okada, Satoshi
• Granted Patent: US 10,090,446 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45139 Silver (Ag) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/45169 Platinum (Pt) as principal constituent
• 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 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/07802 : not being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2933/005 : relating to encapsulations
• CPC Class Codes: H01L 33/52 : Encapsulations
• CPC Class Codes: H01L 33/54 : having a particular shape

Abstract

To provide a light emitting device having high light extraction efficiency, and a method for manufacturing the light emitting device. A method for manufacturing a light emitting device (100) according to the present invention, includes: forming a sealing member (40) for sealing a light emitting element (10) on a base body (30) by dropping, the base body (30) including a conductive member (20) for connecting to the light emitting element (10), and a molding (25) integrally molded with the conductive member (20); the sealing member (10) being formed such that at least a part of a periphery of the sealing member (40) is located on an outward surface (38) of the conductive member (20) or the molding (25), the outward surface facing outward in a top view.

Claims

1. A method for manufacturing a light emitting device, comprising:

forming a sealing member for sealing a light emitting element on a base body by dropping, the base body comprising a conductive member connected to the light emitting element, and a molding integrally molded with the conductive member, the sealing member being formed such that at least a part of a periphery of the sealing member is located on an outward surface of the conductive member or the molding, the outward surface facing outward in a top view.

2. The method according to claim 1, wherein the outward surface is a convex curved surface, or a lower-side surface continuing from the convex curved surface.

3. The method according to claim 1, wherein the outward surface is a flat surface inclined at angle of 45 degrees or less from an upper flat surface continuing from the outward surface.

4. The method according to claim 1, wherein at least a part of an inward surface of the base body facing inward in a top view comprises a convex curved surface at a top part thereof, the part of the inward surface being located at an inner side of the periphery of the sealing member.

5. The method according to claim 1, wherein the base body has a protrusion or a groove, at least the part of the periphery of the sealing member being located on an outward surface of the protrusion or the groove.

6. The method according to claim 5, wherein the base body has a first protrusion or a first groove, and a second protrusion or a second groove located at an outer side of the first protrusion or the first groove, at least the part of the periphery of the sealing member being located on an outward surface of any of the first and second protrusions and the first and second grooves.

7. The method according to claim 6, wherein the sealing member comprises:

a first scaling portion for sealing the light emitting element; and

a second sealing portion for sealing the first scaling portion, the first sealing portion being formed such that at least a part of a periphery of the first sealing portion is located on an outward surface of the first protrusion or the first groove, the second sealing portion being formed such that at least a part of a periphery of the second sealing portion is located on an outward surface of the second protrusion or the second groove.

8. The method according to claim 7, wherein the sealing member contains a phosphor only in the first sealing portion, the phosphor being excited by light emitted from the light emitting element.

9. The method according to claim 5, wherein the protrusion or the groove is rounded at corners or at an entire part in atop view of the base body.

10. The method according to claim 5, wherein the protrusion or the groove is formed in a frame shape surrounding the light emitting element.

11. The method according to claim 1, wherein the base body has a recess inside which the light emitting element is mounted, the periphery of the sealing member being located inside the recess.

12. The method according to claim 1, further comprising, before dropping the sealing member on the base body, forming a coating having a critical surface tension of 50 mN/m or less, only on the outward surface of the base body on which the periphery of the sealing member is located, or on the outward surface as well as a structural surface outside the outward surface.

13. The method according to claim 1, wherein a base material of the sealing member contains a phenyl silicone resin as a major component.

14. A light emitting device, comprising:

a light emitting element;

a base body comprising a conductive member connected to the light emitting element, and a molding integrally molded with the conductive member; and

a sealing member for sealing the light emitting element, at least a part of a periphery of the sealing member being located on an outward surface of the conductive member or the molding, the outward surface facing outward in a top view and making an angle of approximately an contact angle or less to the outward surface or to a tangent plane of the outward surface at a contact point between the outward surface and the periphery of the sealing member.

15. The light emitting device according to claim 14, wherein at least a part of the periphery of the sealing member makes an angle of more than the contact angle to a horizontal plane in a top view of the light emitting device.

16. The light emitting device according to claim 14, wherein the outward surface is a convex curved surface, or a lower-side surface continuing from the convex curved surface.

17. The light emitting device according to claim 14, wherein the outward surface is a flat surface that is inclined at an angle of 45 degrees or less from an upper flat surface continuing from the outward surface.

18. The light emitting device according to claim 14, wherein the base body has a protrusion or a groove, at least a part of the periphery of the sealing member being located on the outward surface of the protrusion or the groove.

19. The light emitting device according to claim 18, wherein the sealing member comprises:

a first sealing portion for sealing the light emitting element; and

a second sealing portion for sealing the first sealing portion, only the first sealing portion containing a phosphor excited by light emitted from the light emitting element, at least a part of a periphery of the second sealing portion being located on the outward surface of the protrusion or the groove.

20. The light emitting device according to claim 18, wherein the base body has a recess inside which the light emitting element is mounted, the protrusion or the groove being located inside the recess.

21. The light emitting device according to claim 18, wherein the base body has a recess inside which the light emitting element is mounted, and

the protrusion or the groove being located at an outer side of the recess.

22. The light emitting device according to claim 18, wherein the protrusion or the groove is formed in a frame shape surrounding the light emitting element.

23. The light emitting device according to claim 21, wherein the protrusion or the groove are formed in a strip shape on both sides of the recess.

24. The light emitting device according to claim 18, wherein the protrusion or the groove is rounded at corners or at an entire part in a top view of the base body.

25. The light emitting device according to claim 14, wherein the base body has a first protrusion or a first groove, and a second protrusion or a second groove at an outer side of the first protrusion or the first groove, the sealing member comprises:

a first sealing portion for sealing the light emitting element; and

a second sealing portion for sealing the first sealing portion, only the first sealing portion containing a phosphor excited by light emitted from the light emitting element, at least a part of a periphery of the first sealing portion being located on an outward surface of the first protrusion or the first groove,

at least a part of a periphery of the second sealing portion being located on an outward surface of the second protrusion or the second groove.

26. The light emitting device according to claim 14, wherein the base body has an inward surface at an outer side of the outward surface on which the periphery of the sealing member is located, the inward surface facing inward in a top view of the base body.

27. The light emitting device according to claim 14, wherein a base material of the sealing member contains a phenyl silicone resin as a major component.

28. A light emitting device, comprising:

a light emitting element;

a base body comprising a conductive member connected to the light emitting element and a molding integrally molded with the conductive member; and

a scaling member for sealing the light emitting element, at least a part of a periphery of the sealing member being located on an outward surface of the conductive member or molding, the outward surface facing outward in a top view, the base body having an inward surface at an outer side of the outward surface on which the periphery of the sealing member is located, the inward surface facing inward in a top view of the base body.

29. A method for manufacturing a light emitting device, comprising:

a first step of forming a protrusion at an outer side of an light emitting element on an upper surface of a wiring substrate on which the light emitting element is mounted; and

a second step of forming a sealing member for sealing the light emitting element by dropping, the sealing member being formed such that at least a part of a periphery of the sealing member is located on an outward surface of the protrusion, the outward surface facing outward in a top view.

30. The method according to claim 29, wherein the outward surface is a convex curved surface, or a lower-side surface continuing from the convex curved surface.

31. The method according to claim 29, wherein the outward surface is a flat surface inclined at an angle of 45 degrees or less from an upper flat surface continuing from the outward surface.

32. The method according to claim 29, wherein the outward surface is inclined so as to face the upper surface of the wiring substrate.

33. The method according to claim 29, wherein at least a part of an inward surface of the protrusion facing inward in a top view comprises a convex curved surface at a top part thereof, the part of the inward surface being located at an inner side of the periphery of the sealing member.

34. The method according to claim 29, wherein in the first step, a first protrusion and a second protrusion located at an outer side of the first protrusion are formed on the upper surface of the wiring substrate, and

in the second step, the sealing member is formed such that at least a part of the periphery of the sealing member is located on an outward surface either one of the first protrusion or the second protrusion.

35. The method according to claim 34,

wherein the sealing member comprises:

a first sealing portion for sealing the light emitting element; and

a second sealing portion for sealing the first sealing portion, the first sealing portion being formed such that at least a part of a periphery of the first sealing portion is located on an outward surface of the first protrusion, the second sealing portion being formed such that at least a part of a periphery of the second sealing portion is located on an outward surface of the second protrusion.

36. The method according to claim 35, wherein the sealing member contains a phosphor only in the first sealing portion, the phosphor being excited by light emitted from the light emitting element.

37. The method according to claim 29, wherein the protrusion is rounded at corners or at an entire part in a top view.

38. The method according to claim 29, wherein the protrusion is formed in a frame shape surrounding the light emitting element.

39. The method according to claim 29, wherein in the first step, a plurality of the light emitting elements are arranged on the wiring substrate, the protrusions being formed on both sides of the light emitting elements in a strip shape extending approximately parallel to an alignment direction of the plurality of light emitting element, and

in the second step, the sealing member is formed so as to bridge between the protrusions on the both sides,

the method further comprises a third step of cutting the sealing member and the wiring substrate at a position between the plurality of light emitting elements after the second step.

40. The method according to claim 29, wherein at least the surface of the protrusion is formed from a material having a critical surface tension of 50 mN/m or less.

41. The method according to claim 29, further comprising, before the second step, forming a coating having a critical surface tension of 50 mN/m or less, only on the outward surface of a base body on which the periphery of the sealing member is located, or on the outward surface as well as a structural surface outside the outward surface, the base body being comprising the wiring substrate and the protrusion.

42. The method according to claim 29, wherein the base material of the sealing member contains a phenyl silicone resin as a major component.

43. A light emitting device, comprising:

a light emitting element;

a wiring substrate having an upper surface on which the light emitting element is mounted comprising a protrusion located at an outer side of the light emitting element on the upper surface; and

a sealing member for sealing the light emitting element, at least a part of a periphery of the sealing member being located on an outward surface of the protrusion, the outward surface facing outward in a top view, and making an angle of approximately an contact angle or less to the outward surface or to a tangent plane of the outward surface at a contact point between the outward surface and the periphery of the sealing member.

44. The light emitting device according to claim 43, wherein at least a part of the periphery of the sealing member makes an angle of more than the contact angle to a horizontal plane in a top view of the light emitting device.

45. The light emitting device according to claim 43, wherein the outward surface is a convex curved surface or a lower-side surface continuing from the convex curved surface.

46. The light emitting device according to claim 43, wherein the outward surface is a flat surface inclined at an angle of 45 degrees or less from an upper flat surface continuing from the outward surface.

47. The light emitting device according to claim 43, wherein the outward surface is inclined so as to face the upper surface of the wiring substrate.

48. The light emitting device according to claim 43, wherein the sealing member comprises:

a first sealing portion for sealing the light emitting element; and

a second sealing portion for sealing the first sealing portion, only the first sealing portion containing a phosphor excited by light emitted from the light emitting element, at least a part of a periphery of the second sealing portion being located on the outward surface of the protrusion.

49. The light emitting device according to claim 43, wherein the protrusion is formed in a frame shape surrounding the light emitting element.

50. The light emitting device according to claim 43, wherein the protrusion is rounded at corners or at an entire part in a top view of the base body.

51. The light emitting device according to claim 43, wherein at least a surface of the protrusion is made of a material having a critical surface tension of 50 mN/m or less.

52. The light emitting device according to claim 43, wherein a base material of the sealing member contains a phenyl silicone resin as a major component.