Light emitting device and method for manufacturing the same

• US 10,090,446 B2
• Filed: 05/15/2012
• Issued: 10/02/2018
• Est. Priority Date: 05/16/2011
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Kuramoto, Masafumi, Iwakura, Daisuke, Ozeki, Kenji, Tsuruha, Tomoaki, Okada, Satoshi, Hayashi, Masaki
• Primary Examiner(s): Lee, Jae
• Application Number:
  US14/118,176
• Publication Number:
  US 20140124812A1
• Time in Patent Office: 2,331 Days
• 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:

providing an assembly comprising;

a base body comprising;

a conductive member, and

a molding that is molded with the conductive member, and

a light emitting element electrically connected to the conductive member; and

forming a sealing member that seals the light emitting element,

wherein said forming of the sealing member comprises dispensing a sealing member material on the base body,

wherein the sealing member is formed such that at least a part of a peripheral edge of the sealing member is located on an outward-facing surface of the conductive member or the molding, and

wherein the outward-facing surface is a convex curved surface, or a lower-side surface continuing from the convex curved surface.

2. The method according to claim 1, wherein at least a part of an inward-facing surface of the base body comprises a convex curved surface at a top part thereof, said at least a part of the inward surface being located at an inner side of the peripheral edge of the sealing member.

3. The method according to claim 1, wherein the base body has a protrusion or a groove, said at least a part of the peripheral edge of the sealing member being located on an outward-facing surface of the protrusion or the groove.

4. The method according to claim 3, 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, said at least a part of the peripheral edge of the sealing member being located on an outward-facing surface of any of the first and second protrusions and the first and second grooves.

5. The method according to claim 4,

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,

wherein the first sealing portion is formed such that at least a part of a peripheral edge of the first sealing portion is located on an outward-facing surface of the first protrusion or the first groove, and the second sealing portion is formed such that at least a part of a peripheral edge of the second sealing portion is located on an outward-facing surface of the second protrusion or the second groove.

6. The method according to claim 5, wherein the sealing member contains a phosphor only in the first sealing portion, the phosphor being excitable by light emitted from the light emitting element.

7. The method according to claim 3, wherein the protrusion or the groove is rounded at corners or at an entire part in a top view of the base body.

8. The method according to claim 3, wherein the protrusion or the groove is formed in a frame shape surrounding the light emitting element.

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

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

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

12. A light emitting device, comprising:

a base body comprising;

a conductive member, and

a molding that is molded with the conductive member;

a light emitting element electrically connected to the conductive member; and

a sealing member that seals the light emitting element,

wherein at least a part of a peripheral edge of the sealing member is located on an outward-facing surface of the conductive member or the molding,

wherein, at a contact point between the outward-facing surface and the peripheral edge of the sealing member, the sealing member makes an angle of approximately a contact angle or less to the outward-facing surface or to a tangent plane of the outward-facing surface, and

wherein the outward-facing surface is a convex curved surface, or a lower-side surface continuing from the convex curved surface.

13. The light emitting device according to claim 12, wherein at least a part of the peripheral edge of the sealing member makes an angle of more than the contact angle to a horizontal plane.

14. The light emitting device according to claim 12, wherein the base body has a protrusion or a groove, said at least a part of the peripheral edge of the sealing member being located on the outward-facing surface of the protrusion or the groove.

15. The light emitting device according to claim 14,

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,

wherein only the first sealing portion contains a phosphor that is excitable by light emitted from the light emitting element, and

wherein at least a part of a peripheral edge of the second sealing portion is located on the outward-facing surface of the protrusion or the groove.

16. The light emitting device according to claim 14, 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.

17. The light emitting device according to claim 14, 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.

18. The light emitting device according to claim 14, wherein the protrusion or the groove is formed in a frame shape surrounding the light emitting element.

19. The light emitting device according to claim 17, wherein the protrusion or the groove are formed in a strip shape on both sides of the recess.

20. The light emitting device according to claim 14, wherein the protrusion or the groove is rounded at corners or at an entire part in a top view of the base body.

21. The light emitting device according to claim 12, 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,

wherein only the first sealing portion contains a phosphor that is excitable by light emitted from the light emitting element,

wherein at least a part of a peripheral edge of the first sealing portion is located on an outward-facing surface of the first protrusion or the first groove, and

wherein at least a part of a peripheral edge of the second sealing portion is located on an outward-facing surface of the second protrusion or the second groove.

22. The light emitting device according to claim 12, wherein the base body has an inward-facing surface at an outer side of the outward-facing surface on which the peripheral edge of the sealing member is located.

23. The light emitting device according to claim 12, wherein a base material of the sealing member contains a phenyl silicone resin as a major component.

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

providing a wiring substrate on which a light emitting element is mounted;

forming a protrusion at an outer side of the light emitting element on an upper surface of the wiring substrate; and

dispensing a sealing member that seals the light emitting element, the sealing member being formed such that at least a part of a peripheral edge of the sealing member is located on an outward-facing surface of the protrusion,

wherein the outward-facing surface is a convex curved surface, or a lower-side surface continuing from the convex curved surface.

25. The method according to claim 24, wherein the outward-facing surface is inclined so as to face the upper surface of the wiring substrate.

26. The method according to claim 24, wherein at least a part of an inward-facing surface of the protrusion comprises a convex curved surface at a top part thereof, said part of the inward-facing surface being located at an inner side of the peripheral edge of the sealing member.

27. The method according to claim 24, wherein in the step of forming the protrusion, 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 step of dispensing the sealing member, the sealing member is formed such that at least a part of the peripheral edge of the sealing member is located on an outward-facing surface either one of the first protrusion or the second protrusion.

28. The method according to claim 27,

wherein the sealing member comprises:

a first sealing portion that seals the light emitting element, and

a second sealing portion that seals the first sealing portion,

wherein the first sealing portion is formed such that at least a part of a peripheral edge of the first sealing portion is located on an outward-facing surface of the first protrusion, and

wherein the second sealing portion is formed such that at least a part of a peripheral edge of the second sealing portion is located on an outward-facing surface of the second protrusion.

29. The method according to claim 28, wherein the sealing member contains a phosphor only in the first sealing portion, the phosphor being excitable by light emitted from the light emitting element.

30. The method according to claim 24, wherein the protrusion is rounded at corners or at an entire part in a top view.

31. The method according to claim 24, wherein the protrusion is formed in a frame shape surrounding the light emitting element.

32. The method according to claim 24,

wherein a plurality of the light emitting elements are arranged on the wiring substrate,

wherein protrusions are 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,

wherein in the step of dispensing the sealing member, the sealing member is formed so as to bridge between the protrusions on the both sides of the light emitting elements, and

wherein the method further comprises, after dispensing the sealing member, cutting the sealing member and the wiring substrate at one or more positions between the plurality of light emitting elements.

33. The method according to claim 24, wherein at least the surface of the protrusion is formed from a material having a critical surface tension of 50 mN/m or less.

34. The method according to claim 24, further comprising, before the step of dispensing the sealing member, forming a coating having a critical surface tension of 50 mN/m or less, only on the outward-facing surface of a base body on which the peripheral edge of the sealing member is located, or on the outward-facing surface as well as a structural surface outside the outward-facing surface, the base body comprising the wiring substrate and the protrusion.

35. The method according to claim 24, wherein a base material of the sealing member contains a phenyl silicone resin as a major component.

36. A light emitting device, comprising:

a light emitting element;

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

a sealing member that seals the light emitting element,

wherein at least a part of a peripheral edge of the sealing member is located on an outward-facing surface of the protrusion,

wherein the sealing member makes an angle of approximately a contact angle or less to the outward-facing surface or to a tangent plane of the outward-facing surface, and

wherein the outward-facing surface is a convex curved surface or a lower-side surface continuing from the convex curved surface.

37. The light emitting device according to claim 36, wherein at least a part of the peripheral edge of the sealing member makes an angle of more than the contact angle to a horizontal plane.

38. The light emitting device according to claim 36, wherein the outward-facing surface is inclined so as to face the upper surface of the wiring substrate.

39. The light emitting device according to claim 36,

wherein the sealing member comprises:

a first sealing portion that seals the light emitting element, and

a second sealing portion that seals the first sealing portion,

wherein only the first sealing portion contains a phosphor that is excitable by light emitted from the light emitting element, and

wherein at least a part of a peripheral edge of the second sealing portion is located on the outward-facing surface of the protrusion.

40. The light emitting device according to claim 36, wherein the protrusion is formed in a frame shape surrounding the light emitting element.

41. The light emitting device according to claim 36, wherein the protrusion is rounded at corners or at an entire part in a top view of the base body.

42. The light emitting device according to claim 36, wherein at least a surface of the protrusion is made of a material having a critical surface tension of 50 mN/m or less.

43. The light emitting device according to claim 36, wherein a base material of the sealing member contains a phenyl silicone resin as a major component.