Light emitting apparatus

• US 20050168992A1
• Filed: 01/11/2005
• Published: 08/04/2005
• Est. Priority Date: 01/13/2004
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Hirose, Minoru
• Granted Patent: US 7,211,832 B2
• Time in Patent Office: Days
• US Class Current: 362/296.40
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/405 Reflective materials

Abstract

A light emitting apparatus has: a support; a wiring layer that is formed on the support; and an LED element that is flip-chip mounted on the wiring layer formed on the support. The wiring layer has: a conductive layer that is formed on the support and is electrically connected to an electrode of the LED element; and a reflection layer that is formed on the conductive layer that has a light reflection property to allow a radiated light from the LED element to be reflected thereon. The reflection layer is of a material that generates no intermetallic compound to a material of the conductive layer.

Claims

1. A light emitting apparatus, comprising:

a support;

a wiring layer that is formed on the support; and

an LED element that is flip-chip mounted on the wiring layer formed on the support,

wherein the wiring layer comprises;

a conductive layer that is formed on the support and is electrically connected to an electrode of the LED element; and

a reflection layer that is formed on the conductive layer that has a light reflection property to allow a radiated light from the LED element to be reflected thereon, and

the reflection layer is of a material that generates no intermetallic compound to a material of the conductive layer.

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

the reflection layer is partially removed in accordance with the electrode of the LED element to expose a surface of the conductive layer, and

the conductive layer is electrically connected through a bump material to the electrode of the LED element at the exposed surface.

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

the conductive layer is of Au, and

the reflection layer is of Cr or Ag alloys.

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

the conductive layer comprises multiple layers which each are of Au, Pt and Ti, the multiple layers being formed in this order on the support, and

the reflection layer is of Cr or Ag alloys.

5. A light emitting apparatus, comprising:

a support;

an LED element that is flip-chip mounted on the support; and

a wiring layer that is formed on the support,

wherein the wiring layer comprises;

a conductive layer that is formed on the support and is electrically connected to an electrode of the LED element;

a reflection layer that is formed on the conductive layer that has a light reflection property to allow a radiated light from the LED element to be reflected thereon; and

a barrier metal layer that is formed between the conductive layer and the reflection layer and is of a material that prevents the generation of an intermetallic compound between the conductive layer and the reflection layer.

6. The light emitting apparatus according to claim 5, wherein:

the reflection layer and the barrier layer are partially removed in accordance with the electrode of the LED element to expose a surface of the conductive layer, and

the conductive layer is electrically connected through a bump material to the electrode of the LED element at the exposed surface.

7. The light emitting apparatus according to claim 5, wherein:

the reflection layer is of Al, and

the barrier metal layer is of one or more of Cr₂O₃, Cr, Ti and TiN.

8. The light emitting apparatus according to claim 7, wherein:

the conductive layer comprises multiple layers which each are of Au, Pt and Ti, the multiple layers being formed in this order on the support.

9. A light emitting apparatus, comprising:

a support;

an LED element that is flip-chip mounted on the support; and

a wiring layer that is formed on the support,

wherein the wiring layer comprises;

a conductive layer that is formed on the support and is electrically connected to an electrode of the LED element; and

a reflection layer that is formed on the conductive layer that has a light reflection property to allow a radiated light from the LED element to be reflected thereon;

the conductive layer comprises a barrier metal layer that prevents an aggregation in a material of the reflection layer.

10. The light emitting apparatus according to claim 9, wherein:

the reflection layer is partially removed in accordance with the electrode of the LED element to expose a surface of the conductive layer, and

the conductive layer is electrically connected through a bump material to the electrode of the LED element at the exposed surface.

11. The light emitting apparatus according to claim 9, wherein:

the reflection layer is of Ag alloys, and

the barrier metal layer is of one or more of Cr₂O₃, Cr, Ti and TiN.

12. A light emitting apparatus, comprising:

a support;

an LED element that is flip-chip mounted on the support; and

a wiring layer that is formed on the support,

wherein the wiring layer comprises;

a conductive layer that is formed on the support and is electrically connected to an electrode of the LED element; and

a reflection layer that is formed on the conductive layer that has a light reflection property to allow a radiated light from the LED element to be reflected thereon;

wherein the reflection layer is partially removed in accordance with the electrode of the LED element to expose a surface of the conductive layer, and the conductive layer is electrically connected through a bump material to the electrode of the LED element at the exposed surface.