LED illuminator and method of making the same

Patent metadata

Field	Value
Publication number	US-10312285-B2
Application number	US-201615276478-A
Country	US
Kind code	B2
Filing date	Sep 26, 2016
Priority date	Sep 30, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

An LED illuminator includes an LED chip and an opaque resin member. The LED chip includes a support substrate, a semiconductor layer disposed on the obverse surface of the support substrate, an electrode formed on the reverse surface of the support substrate. The obverse surface of the support substrate has a peripheral edge portion exposed from the semiconductor layer. The opaque resin member covers at least apart of the side surface of the support substrate while exposing the peripheral edge portion of the obverse surface of the support substrate.

First claim

The invention claimed is:

1. An LED illuminator, comprising:
at least one LED chip including a first LED chip; and
an opaque resin member that does not transmit light from the LED chip,
wherein the LED chip includes: a support substrate having an obverse surface, a reverse surface and a side surface located between the obverse surface and the reverse surface; a semiconductor layer disposed on the obverse surface of the support substrate; and a first electrode formed on the reverse surface of the support substrate,
the obverse surface of the support substrate has a peripheral edge portion exposed from the semiconductor layer,
the opaque resin member covers at least a part of the side surface of the support substrate and exposing the peripheral edge portion of the obverse surface,
the semiconductor layer has a curved surface located at an end of the semiconductor layer in plan view, the curved surface being curved in a recessed shape in a cross-sectional view taken along a plane that is parallel to a thickness direction of the semiconductor layer,
the semiconductor layer has a first surface and a second surface that faces a side opposite the first surface, the second surface of the semiconductor layer being disposed between the first surface of the semiconductor layer and the obverse surface of the support substrate,
the first surface of the semiconductor layer is smaller in dimension in a lateral direction perpendicular to the thickness direction than the second surface of the semiconductor layer,
the LED chip includes a second electrode that is disposed on the first surface of the semiconductor layer,
the first surface of the semiconductor layer includes an exposed portion that is exposed from the second electrode,
the curved surface of the semiconductor layer includes a first end and a second end, the first end of the curved surface being connected to the first surface of the semiconductor layer, the second end of the curved surface being connected to the obverse surface of the support substrate, and
a dimension of the exposed portion of the first surface of the semiconductor layer in the lateral direction is larger than a distance between the first end of the curved surface and the second end of the curved surface in the lateral direction.

2. The LED illuminator according to claim 1 , wherein an entirety of the support substrate is electroconductive.

3. The LED illuminator according to claim 1 , wherein the opaque resin member is white.

4. The LED illuminator according to claim 1 , wherein the opaque resin member is made of a silicone resin containing titanium oxide.

5. The LED illuminator according to claim 4 , wherein the opaque resin member comprises 5 to 50% of the titanium oxide.

6. The LED illuminator according to claim 4 , wherein the opaque resin member comprises 20% of the titanium oxide.

7. The LED illuminator according to claim 1 , wherein the opaque resin member covers an entirety of the side surface of the support substrate.

8. The LED illuminator according to claim 1 , wherein the semiconductor layer emits red light.

9. The LED illuminator according to claim 1 , further comprising a base substrate including a base material and a wiring pattern, wherein the first LED chip is mounted on the base substrate.

10. The LED illuminator according to claim 9 , wherein the first electrode is electrically connected to the wiring pattern.

11. The LED illuminator according to claim 10 , further comprising a plurality of terminals arranged in the lateral direction, each of the terminals being electrically connected to the wiring pattern,
wherein each of the terminals is circular in plan view.

12. The LED illuminator according to claim 10 , wherein the curved surface of the semiconductor layer is connected to the first and second surfaces of the semiconductor layer,
the curved surface of the semiconductor layer is disposed between the first and second surfaces of the semiconductor layer in the thickness direction,
and
the wire is bonded on the first surface of the semiconductor layer via the second electrode.

13. The LED illuminator according to claim 9 , further comprising a terminal electrically connected to the wiring pattern.

14. The LED illuminator according to claim 9 , further comprising a wire, wherein the second electrode and the wiring pattern are electrically connected to each other by the wire.

15. The LED illuminator according to claim 1 , further comprising a second LED chip, a first wire connected to the first LED chip, and a second wire connected to the second LED chip, wherein a direction in which the first wire extends from the first LED chip in plan view is different from a direction in which the second wire extends from the second LED chip in plan view.

16. The LED illuminator according to claim 1 , further comprising a reflector and a light-transmitting sealing resin member, wherein the reflector has a reflecting surface surrounding the first LED chip, and the light-transmitting sealing resin member covers the semiconductor layer.

17. The LED illuminator according to claim 16 , wherein the light-transmitting sealing resin member covers the peripheral edge portion of the obverse surface.

18. The LED illuminator according to claim 16 , wherein the opaque resin member has a top surface, the whole top surface of the opaque resin member being held in contact with the light-transmitting sealing resin member,
the top surface of the opaque resin member includes an edge held in contact with the side surface of the support substrate,
the side surface of the support substrate includes a part exposed from the top surface of the opaque resin, and
the edge of the top surface is located at a lower position in the thickness direction than both the peripheral edge portion of the obverse surface and the curved surface of the semiconductor layer.

19. The LED illuminator according to claim 18 , wherein the top surface of the opaque resin member includes a first portion, and
the first portion of the top surface is located at a higher position in the thickness direction than both the peripheral edge portion of the obverse surface and the second surface of the semiconductor substrate, and overlaps the curved surface of the semiconductor layer in the thickness direction.

20. The LED illuminator according to claim 16 , further comprising two diodes, and wherein, in plan view, each of the reflector and one of the at least one LED chip is disposed between the two diodes.

21. The LED illuminator according to claim 20 , wherein each of the two diodes include a first edge and a second edge that is larger in dimension in plan view than the first edge, and
in plan view, the first edge of one of the two diodes is perpendicular to the first edge of the other one of the two diodes.

22. The LED illuminator according to claim 16 , wherein the curved surface of the semiconductor layer is exposed from the opaque resin, and held in contact with the light-transmitting sealing resin member.

23. The LED illuminator according to claim 1 , wherein the at least one LED chip includes five LED chips, and in plan view, one of the five LED chips is disposed between two others of the five LED chips and between the other two others of the five LED chips.

24. The LED illuminator according to claim 1 , wherein a center of the second electrode in the lateral direction is offset in the lateral direction from a center of the first surface of the sem

Assignees

• Rohm Co Ltd

Inventors

• Mizuta Shinsei

Classifications

• H10W72/01515

  Forming coatings · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W72/075

  of bond wires · CPC title

• H01L33/56

  Electricity · mapped topic

• H01L2224/8592

  Electricity · mapped topic