Light source device using LED, and method of producing same

• US 6,874,910 B2
• Filed: 12/03/2001
• Issued: 04/05/2005
• Est. Priority Date: 04/12/2001
• Status: Expired due to Term

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Asahi Matsushita Electric Works Ltd. (Panasonic Holdings Corporation)
• Inventors: Kobayashi, Mitsuru, Nakagawa, Kazuya, Hashizume, Jiro, Suzuki, Toshiyuki, Sugimoto, Masaru, Kimura, Hideyoshi, Shiohama, Eiji, Hashimoto, Takuma
• Primary Examiner(s): Sember, Thomas M.
• Assistant Examiner(s): Truong, Bao Q.
• Application Number:
  US10/398,660
• Publication Number:
  US 20030189830A1
• Time in Patent Office: 1,219 Days
• Field of Search: 362/294, 362/293, 362/310, 362/267, 362/800, 362/555, 362/545, 362/373, 362/265, 257/100, 257/98, 257/712, 438/116, 438/28, 438/29, 438/64
• US Class Current: 362/294
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• 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 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• 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 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/01068 Erbium [Er]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15165 : Monolayer substrate
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/20752 : larger or equal to 20 microns less than 30 microns
• CPC Class Codes: H01L 33/60 : Reflective elements
• CPC Class Codes: H01L 33/642 : characterized by the shape
• CPC Class Codes: H01L 33/647 : the elements conducting electric current to or from the semiconductor body
• CPC Class Codes: Y10S 362/80 : Light emitting diode

Abstract

A light source apparatus having a radiator plate having thermally conductive properties and an insulating member coupled to at least one side of the radiator plate having a through hole provided in a side thereof facing the radiator plate. The light source apparatus further including a LED chip installed and thermally coupled to an exposed portion of the radiator plate facing the through hole, an extension inwardly projecting at the through hole from the radiator plate end of the insulating member, and a wiring pattern provided on the insulating member electrically isolated by the insulating member from the radiator plate. The light source apparatus also including bonding wires electrically connecting portions of the wiring pattern on the extension and the electrodes of the LED chip, and a light-transmissive sealing material filling the through hole for entirely encapsulating the LED chip and the bonding wires.

Claims

1. A light source apparatus for emitting light from a LED chip, comprising:

a radiator plate having thermally conductive properties;

an insulator positioned on at least one side of the radiator plate having a through hole facing the radiator plate;

the LED chip being mounted on and thermally coupled to an exposed portion of the radiator plate facing the through hole;

a wiring pattern positioned on the insulator and electrically isolated by the insulator from the radiator plate;

connectors that electrically connect the wiring pattern to electrodes of the LED chip; and

sealing material in the through hole that entirely encapsulates the LED chip and the connectors,

wherein portions of the wiring pattern electrically connected by the connectors to the LED chip are located in a bottom of the through hole adjacent to the radiator plate.

2. The light source apparatus according to claim 1, wherein the portions of the wiring pattern electrically connected by the connectors to the LED chip are located in the through hole which is filled to an opening of the through hole with the sealing material.

3. The light source apparatus according to claim 1, wherein the insulator has an inwardly projecting extension at the radiator plate side of the through hole and on which at least portions of the wiring pattern are arranged, the radiator plate has a projection provided on the insulator side configured for insertion into the through hole in the insulator and on which the LED chip is arranged and thermally coupled to the radiator, and the portions of the wiring pattern on the extension are electrically connected to the electrodes of the LED chip.

4. The light source apparatus according to claim 3, wherein the connectors are metal wires, and a portion of the LED chip to which each metal wire is connected at one end is substantially flush with a portion of the wiring pattern to which the other end of each metal wire is connected.

5. The light source apparatus according to claim 3, wherein the top of the projection on which the LED chip is mounted is substantially flush with a portion of the wiring pattern to which the LED chip is electrically connected.

6. The light source apparatus according to claim 3, wherein the projection comprises a stamping of the radiator plate from the side opposite to the insulator side having a raised region corresponding to the insulator side.

7. The light source apparatus according to claim 3, wherein the radiator plate comprises a base plate having a through hole for communicating with the through hole of the insulator and a projection configured to fit into the through hole of the insulator and to extend into the insulator to form the projection.

8. The light source apparatus according to claim 3, wherein there is a gap between the through hole and the projection.

9. The light source apparatus according to claim 1, wherein at least one of the insulator and the radiator plate has a groove adjacent the through hole on a the coupling side thereof that is configured to accept an adhesive for coupling the insulator and the radiator plate.

10. The light source apparatus according to claim 1, wherein the radiator plate comprises an electrically conductive material and is configured to serve as a portion of the wiring pattern for electrically connecting the radiator plate to the LED chip.

11. The light source apparatus according to claim 10, wherein the radiator plate comprises at least two radiator plate segments which are electrically isolated from each other.

12. The light source apparatus according to claim 1, wherein the sealing material is arranged, at a surface, in a lens shape for irradiating the light emitted from the LED chip in a desired direction.

13. The light source apparatus according to claim 1, wherein a side wall of the through hole of the insulator is covered with a reflective coating for reflecting the light emitted from the LED chip in a desired direction.

14. The light source apparatus according to claim 1, wherein the sealing material has a color for converting at least a part of the light emitted from the LED chip into a desired color light.

15. The light source apparatus according to claim 14, wherein the sealing material is located closer to the radiator plate side than the other side of the insulator and the side wall at the through hole of the insulator is covered with a reflective coating for reflecting the light emitted from the LED chip in a desired direction.

16. The light source apparatus according to claim 1, wherein end portions of the wiring pattern extend to the radiator plate and are configured to serve as external connector terminals.

17. The light source apparatus according to claim 16, wherein the end portions of the wiring pattern extend to the radiator plate side of the insulator.

18. The light source apparatus according to claim 16, wherein portions of the insulator extend to the radiator plate where they are substantially flush with the other side of the radiator plate opposite to the insulator side.

19. The light source apparatus according to claim 1, wherein a combination of the insulator, the LED chip, the wiring pattern, and the sealing material are provided on each side of the radiator plate.

20. A method of producing a light source apparatus for emitting light from a LED chip comprising:

preparing an insulator which has a through hole provided therein to extend from a front side for emitting the light to a back side;

providing a wiring pattern on the front side of the insulator for feeding power to the LED chip;

coupling a thermally conductive radiator plate to the back side of the insulator;

installing and thermally coupling the LED chip to a corresponding portion of the radiator plate projected from the through hole and electrically connecting electrodes of the LED chip to the wiring pattern by connectors; and

filling the through hole with a sealing material to entirely encapsulate the LED chip and the connectors.

21. A method of producing a light source apparatus for emitting light from an LED chip, comprising:

forming an insulator of an insulating material that has a through hole, the insulator through hole having a front side for emitting the light and a back side, and a radiator plate which has thermally conductive properties coupled to the back side of the insulator;

providing a wiring pattern on the front side of the insulator for feeding power to the LED chip;

installing and thermally coupling the LED chip to a corresponding portion of the radiator plate projecting from the through hole and electrically connecting electrodes of the LED chip to the wiring pattern by connectors; and

filling the through hole with a sealing material to entirely encapsulate the LED chip and the connectors.

22. A method of producing a light source apparatus for emitting light from a LED chip, comprising:

preparing a thermally conductive radiator plate and an electrically conductive sheet to serve as a wiring pattern for feeding power to the LED chip;

plating the radiator plate and the electrically conductive sheet;

forming the electrically conductive sheet spaced from the radiator plate and forming an insulator of an insulating material;

installing and thermally coupling the LED chip to a corresponding portion of the radiator plate projected from a through hole provided in the insulator, the through hole having a front side for emitting the light and a back side, and electrically connecting the electrodes of the LED chip to the wiring pattern by connectors; and

filling the through hole with a light-transmissive sealing material to entirely encapsulate the LED chip and the connectors.