Semiconductor light emitting device

• US 9,035,333 B2
• Filed: 12/13/2013
• Issued: 05/19/2015
• Est. Priority Date: 11/05/2010
• Status: Active Grant

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Toyama, Tomoichiro
• Primary Examiner(s): Blum, David S
• Application Number:
  US14/105,437
• Publication Number:
  US 20140103370A1
• Time in Patent Office: 522 Days
• Field of Search: 257/88, 257/98, 257/99, 257/E33.062, 257/E33.072
• US Class Current: 257/88
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• 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 33/52 Encapsulations
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective 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 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

A semiconductor light emitting device includes an LED chip, which includes an n-type semiconductor layer, active layer, and p-type semiconductor layer stacked on a substrate. The LED chip further includes an anode electrode connected to the p-type semiconductor, and a cathode connected to the n-type semiconductor. The anode and cathode electrodes face a case with the LED chip mounted thereon. The case includes a base member including front and rear surfaces, and wirings including a front surface layer having anode and cathode pads formed at the front surface, a rear surface layer having anode and cathode mounting electrodes formed at the rear surface, an anode through wiring connecting the anode pad and the anode mounting electrode and passing through a portion of the base member, and a cathode through wirings connecting the cathode pad and the cathode mounting electrode and passing through a portion of the base member.

Claims

1. A semiconductor light emitting device, comprising:

an LED chip;

a case comprising a front surface on which the LED chip is mounted, and a rear surface opposite to the front surface, the case further including;

a base member having an inner wall surface surrounding the LED chip; and

a reflective resin including;

an internal edge disposed at the LED chip side;

an external edge contacting the inner wall surface; and

a reflective surface connecting the internal edge and the external edge, the reflective surface being inclined to be receded from the front surface from the internal edge to the external edge; and

a bypass function element preventing a reverse overvoltage from being applied to the LED chip, the reflective resin covering the bypass function element.

2. The semiconductor light emitting device of claim 1, wherein the reflective resin has a reflectivity higher than that of the base member.

3. The semiconductor light emitting device of claim 1, wherein the base member is formed of ceramic.

4. The semiconductor light emitting device of claim 1, wherein,

the case is electrically connected to the LED chip, and comprises a lead, at least a portion of the lead being covered by the base member, and

the base member comprises thermosetting resin or thermoplastic resin.

5. The semiconductor light emitting device of claim 1, wherein a height from the front surface to the external edge is greater than a height from the front surface to an active layer of the LED chip.

6. The semiconductor light emitting device of claim 1, wherein the inner wall surface is perpendicular to the front surface.

7. The semiconductor light emitting device of claim 1, wherein the reflective resin covers a wire connected to the bypass function element.

8. The semiconductor light emitting device of claim 1, wherein the base member is recessed from the front surface toward the rear surface, and comprises a stopping concave portion separated from the LED chip and configured to receive the bypass function element.

9. The semiconductor light emitting device of claim 8, wherein the internal edge is matched with an end edge of the stopping concave portion.

10. The semiconductor light emitting device of claim 8, wherein the stopping concave portion receives a pad which is bonded to the wire connected to the bypass function element.

11. The semiconductor light emitting device of claim 8, wherein the stopping concave portion comprises a surrounding portion surrounding the LED chip.

12. The semiconductor light emitting device of claim 11, comprising a plurality of the LED chips,

wherein the reflective resin comprises a protruding portion disposed between the LED chips adjacent to each other in the surrounding portion.

13. The semiconductor light emitting device of claim 12, further comprising another LED chip disposed at a center of the case.

14. The semiconductor light emitting device of claim 1, wherein the LED chip has a flip chip type structure in which an anode electrode and a cathode electrode of the LED chip face the front surface.

15. The semiconductor light emitting device of claim 14, wherein the internal edge of the reflective resin is separated from the LED chip.

16. The semiconductor light emitting device of claim 1, wherein the LED chip has a 2-wire type structure in which an anode electrode and a cathode electrode of the LED chip are connected to a wire.

17. The semiconductor light emitting device of claim 16, wherein the internal edge of the reflective resin is separated from the LED chip.

18. The semiconductor light emitting device of claim 16, wherein the case comprises an anode pad and a cathode pad which are bonded to the wire connected to the LED chip, the anode pad and the cathode pad being disposed outside the LED chip.

19. The semiconductor light emitting device of claim 18, wherein the reflective resin covers the anode pad and the cathode pad.

20. The semiconductor light emitting device of claim 1, wherein the LED chip comprises an n-type semiconductor layer, a p-type semiconductor layer, an active layer disposed between the n-type semiconductor layer and the p-type semiconductor layer, and a sub mount substrate supporting the layers, the n-type semiconductor layer, the active layer, the p-type semiconductor layer being stacked on the sub mount substrate.

21. The semiconductor light emitting device of claim 20, wherein the reflective resin covers an entire portion of the front surface surrounded by the inner wall surface other than a portion connected to the sub mount substrate.

22. The semiconductor light emitting device of claim 1, comprising a sealing resin covering the LED chip and the reflective resin, and formed of a material which is obtained by mixing a phosphor material with transparent resin which transmits light from the LED chip, the phosphor material being excited by light from the LED chip to emit light of a wavelength different from the light from the LED chip.

23. The semiconductor light emitting device of claim 1, wherein,

the case comprises:

a front surface layer;

a rear surface layer;

an anode through wiring; and

a cathode through wiring,

the front surface layer comprises an anode pad and a cathode pad which are formed at the front surface of the base member,

the rear surface layer comprises an anode mounting electrode and a cathode mounting electrode which are formed at the rear surface of the base member,

the anode through wiring electrically connects the anode pad and the anode mounting electrode, and passes through at least a portion of the base member in a thickness direction of the base member, and

the cathode through wiring electrically connects the cathode pad and the cathode mounting electrode, and passes through at least a portion of the base member in the thickness direction of the base member.