LIGHT-EMITTING APPARATUS AND METHOD OF PRODUCING THE SAME

• US 20080149960A1
• Filed: 12/21/2007
• Published: 06/26/2008
• Est. Priority Date: 12/26/2006
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: OKADA, Satoshi, HODONO, Yoshifumi, NISHIJIMA, Shinji, AMO, Takahiro
• Granted Patent: US 7,687,823 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/32188 the layer connector connecting to a bonding area protruding from the surface of the item
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• 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 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

A light-emitting apparatus includes a package including a support having a central section and a peripheral section around the central section. The central section is raised upwardly from the peripheral section, providing a pedestal for supporting a light-emitting device. A light-emitting device secured on an upper surface of the pedestal and has electrodes. Electrically conductive members are provided on a peripheral region of the package and electrically connected to the electrodes of the light-emitting device. A color conversion layer covers the light-emitting device. A light-transmitting member is formed in the package, sealing at least the light-emitting device together with the color conversion layer. The pedestal has its side surface at least partially exposed from the color conversion layer.

Claims

1. A light-emitting apparatus comprising:

a package comprising a support having a central section and a peripheral section around the central section, the central section being raised upwardly from the peripheral section, providing a pedestal for supporting a light-emitting device;

a light-emitting device secured on an upper surface of the pedestal and having electrodes;

electrically conductive members provided on a peripheral region of the package and electrically connected to the electrodes of the light-emitting device;

a color conversion layer covering the light-emitting device; and

a light-transmitting member formed in the package, sealing at least the light-emitting device together with the color conversion layer;

wherein the pedestal has its side surface at least partially exposed from the color conversion layer.

2. The Light-emitting apparatus according to claim 1, wherein the color conversion layer is deposited substantially uniformly on the light-emitting device and on the peripheral section.

3. The light-emitting apparatus according to claim 1, wherein the color conversion layer comprises a portion of phosphor material which has been contained in the light-transmitting member and settled onto the light-emitting device.

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

the light-emitting device is secured by a die-bonding member,

the die-bonding member covers a covering region extending from a lower edge of a side surface of the light-emitting device upwardly on a side surface of the device up to a position immediately below a position where a light-emitting layer of the light-emitting device is exposed, and

the color conversion layer covers a side surface of the device above the covering region, and also a side surface of the light-emitting layer.

5. The light-emitting apparatus according to claim 1, wherein a central region of the upper surface of the pedestal is recessed, the light-emitting device is placed in the recess, and the color conversion layer is deposited thicker on the side surface of the light-emitting device than on the upper surface of the light-emitting device.

6. The light-emitting apparatus according to claim 5, wherein the recess has a depth such that a light-emitting layer of the light-emitting device is positioned higher than the upper surface of the pedestal.

7. The light-emitting apparatus according to claim 1, wherein the color conversion layer is locally formed on the upper surface of the pedestal.

8. The light-emitting apparatus according to claim 1, wherein the light-transmitting member has a first portion containing a phosphor material covering the light-emitting device on the upper surface of the pedestal, and a second portion covering the first portion.

9. The light-emitting apparatus according to claim 1, wherein the package includes an insulating substrate having a central through-hole therein, and the support is made of a metallic material and is inserted into the through-hole such that the upper surface of the pedestal is positioned higher than the upper surface of the substrate.

10. The light-emitting apparatus according to claim 1, wherein the color conversion layer comprises a mixture of a phosphor material effecting the color conversion and a light-diffusing additive.

11. The light-emitting apparatus according to claim 1, wherein the color conversion layer comprises a phosphor material and a light-diffusing additive having substantially the same particle size and specific gravity, which have been contained in the light-transmitting member and have been settled down.

12. A method of producing a light-emitting apparatus, the apparatus comprising a package comprising a support having a central section and a peripheral section around the central section, the central section being raised upwardly from the peripheral section, providing a pedestal for supporting a light-emitting device;

a light-emitting device secured on an upper surface of the pedestal and having electrodes;

electrically conductive members provided on a peripheral region of the package and electrically connected to the electrodes of the light-emitting device;

a color conversion layer covering the light-emitting device; and

a light-transmitting member formed in the package, sealing at least the light-emitting device together with the color conversion layer, the method comprising depositing a phosphor material which has been contained in the light-transmitting member by settling down the phosphor material onto the pedestal, forming the color conversion layer, such that the color conversion layer is discontinued at a step between the upper surface of the pedestal and the upper surface of the peripheral section, thereby exposing a portion of the side surface of the pedestal exposed from the color conversion layer.