Light emitting diode and light emitting diode array

• US 20040169466A1
• Filed: 12/10/2003
• Published: 09/02/2004
• Est. Priority Date: 12/24/2002
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Kato, Hideaki, Suehiro, Yoshinobu, Inoue, Mitsuhiro, Takashima, Tatsuya
• Granted Patent: US 6,998,777 B2
• Time in Patent Office: Days
• US Class Current: 313/512
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

A light emitting diode has: a ceramics substrate that has a high thermal conductivity; a light emitting element that is mounted on the ceramics substrate; and a radiation plate that is bonded to the back surface of the ceramics substrate. The radiation plate contacts the ceramics substrate at a contact region that includes a region of the back surface of the ceramics substrate corresponding to a region of the ceramics substrate on which the light emitting element is mounted.

Claims

1. A light emitting diode, comprising:

a ceramics substrate that has a high thermal conductivity;

a light emitting element that is mounted on the ceramics substrate; and

a radiation plate that is bonded to the back surface of the ceramics substrate;

wherein the radiation plate contacts the ceramics substrate at a contact region that includes a region of the back surface of the ceramics substrate corresponding to a region of the ceramics substrate on which the light emitting element is mounted.

2. The light emitting diode according to claim 1, wherein:

the light emitting element is flip-chip mounted on the ceramics substrate.

3. The light emitting diode according to claim 1, wherein:

the radiation plate is of a metal and is folded into waveform outside the ceramics substrate.

4. The light emitting diode according to claim 1, wherein:

the radiation plate has a plurality of penetrating holes.

5. The light emitting diode according to claim 1, wherein:

the radiation plate is of a metal and is provided with a plurality of radiation fins that are formed by making a cut in the radiation plate and folding the inside portion of the cut.

6. A light emitting diode array, comprising:

a ceramics substrate that has a high thermal conductivity;

a light emitting element that is mounted on the ceramics substrate; and

a radiation plate that is bonded to the back surface of the ceramics substrate;

wherein the radiation plate contacts the ceramics substrate at a contact region that includes a region of the back surface of the ceramics substrate corresponding to a region of the ceramics substrate on which the light emitting element is mounted; and

a circuit board on which the plurality of light emitting diodes are mounted, the circuit board including a through-hole.

7. A light emitting diode, comprising:

a circuit board that includes a plurality of penetrating holes, each of which having a narrowed portion;

a ceramics substrate that is mounted on the circuit board while bridging the narrowed portion, the ceramics substrate having a high thermal conductivity;

a light emitting element that is mounted on a circuit pattern of the ceramics substrate; and

a radiation plate that is bonded to the back surface of the ceramics substrate and extends in one of the plurality of penetrating holes without contacting the edge of the one of the plurality of penetrating holes and;

wherein the circuit pattern of the ceramics substrate is electrically connected to a circuit pattern of the circuit board at the bridged narrowed portion.

8. A light emitting diode array, comprising a plurality of the light emitting diodes defined in claim 7.

9. The light emitting diode according to claim 7, wherein:

the radiation plate has a plurality of penetrating holes.

10. The light emitting diode array according to claim 8, wherein:

the radiation plate has a plurality of penetrating holes.

11. The light emitting diode according to claim 7, wherein:

the radiation plate is of a metal and is provided with a plurality of radiation fins that are formed by making a cut in the radiation plate and folding the inside portion of the cut.

12. The light emitting diode array according to claim 8, wherein:

the radiation plate is of a metal and is provided with a plurality of radiation fins that are formed by making a cut in the radiation plate and folding the inside portion of the cut.

13. A light emitting diode, comprising:

a substrate that has a low coefficient of thermal expansion and a high thermal resistance;

a circuit pattern that is formed using a conductive material on the substrate;

a light emitting element that is mounted on the surface of the substrate;

a metal member that electrically connects the light emitting element to the circuit pattern;

a glass lens that covers the periphery of the light emitting element while leaving a space and a resin injection hole, the space being defined to house the light emitting element and the metal member;

a sealing material that seals the surface of the substrate and the glass lens; and

light transmitting resin that is filled in the space by injecting the resin through the resin injection hole.

14. The light emitting diode according to claim 13, wherein:

the sealing material has a coefficient of thermal expansion between the substrate and the glass lens.

15. The light emitting diode according to claim 13, wherein:

the sealing material is of sealing glass.

16. The light emitting diode according to claim 13, wherein:

the light transmitting resin is transparent silicone resin.

17. The light emitting diode according to claim 13, wherein:

the substrate has a resin injection hole that penetrates through the substrate and communicates with the space, instead of the resin injection hole defined by the glass lens.