Light-emitting device and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-9310062-B2
Application number	US-201313922173-A
Country	US
Kind code	B2
Filing date	Jun 19, 2013
Priority date	Jul 24, 2012
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

A light-emitting device includes a base material having a conductor layer on a surface thereof, the conductor layer being configured to be connected to an external power source, a light-emitting element mounted on the base, a phosphor layer arranged above the light-emitting element, and a resin layer contacting both of the phosphor layer and the conductor layer and containing heat-conductive particles dispersed therein. The heat-conductive particles have a thermal conductivity of not less than 100 W/m·K and an insulator property or a semiconductor property.

First claim

What is claimed is:

1. A light-emitting device, comprising:
a base material comprising a conductor layer on a surface thereof, the conductor layer being configured to be connected to an external power source;
a light-emitting element mounted on the base material;
a phosphor layer arranged above the light-emitting element; and
a resin layer contacting both of the phosphor layer and the conductor layer and comprising heat-conductive particles dispersed therein so as to decrease a thermal resistance between the phosphor layer and the conductor layer,
wherein the heat-conductive particles have a thermal conductivity of not less than 100 W/mK and an electrical insulator property or a semiconductor property,
wherein the resin layer comprises the base material,
wherein the base material further comprises a recessed portion and white pigment particles, and
wherein the light-emitting element is mounted on a bottom surface of the recessed portion.

2. The light-emitting device according to claim 1 , further comprising a white resin portion between the light-emitting element and the base material.

3. The light-emitting device according to claim 2 , wherein the phosphor layer is in contact with the light-emitting element.

4. The light-emitting device according to claim 3 , further comprising a sealing portion between the light-emitting element and the white resin portion,
wherein the sealing portion is in contact with and seals the light-emitting element.

5. The light-emitting device according to claim 1 , wherein the resin layer comprises a resin sealing portion contacting and sealing the light-emitting element,
wherein an upper portion of the sealing portion away from the light-emitting element has a phosphor particle concentration higher than a lower portion of the sealing portion in contact with the light-emitting element, and
wherein the heat-conductive particles are dispersed at least in the lower portion of the sealing portion.

6. The light-emitting device according to claim 1 , wherein the heat-conductive particles comprise at least one of a carbon nanotube (CNT), diamond, cubic boron nitride (c-BN), SiC, BeO and MN.

7. A method of manufacturing the light-emitting device according to claim 5 , comprising:
forming the lower portion of the sealing portion by supplying a first sealing material containing the heat-conductive particles so as to be in contact with the light-emitting element; and
forming the upper portion of the sealing portion by supplying a second sealing material containing the phosphor particles on a surface of the first sealing material.

8. A method of manufacturing the light-emitting device according to claim 5 , comprising:
supplying a thermosetting sealing material so as to be in contact with the light-emitting element, the thermosetting sealing material containing the heat-conductive particles and the phosphor particles having greater specific gravity than that of the heat-conductive particles;
while maintaining the light-emitting device so that gravity acts toward a surface of the thermosetting sealing material, decreasing viscosity of the thermosetting sealing material by heating at a first temperature to precipitate the phosphor particles in the thermosetting sealing material on the surface side; and
curing the thermosetting sealing material by heating at a second temperature higher than the first temperature.

9. The light-emitting device according to claim 1 , wherein the resin layer is formed on the light-emitting element such that the heat-conductive particles are dispersed in the resin layer between the light-emitting element and the phosphor layer.

10. The light-emitting device according to claim 1 , wherein the heat-conductive particles conduct heat generated by the phosphor layer to the conductor layer for dissipating the heat.

11. The light-emitting device according to claim 1 , wherein the base material comprises a package of the light-emitting device.

12. The light-emitting device according to claim 11 , wherein the conductor layer comprises a pair of leads which are connected by wires to positive and negative electrodes on the light-emitting element, and the pair of leads protrude outward from a side surface of the package.

13. The light-emitting device according to claim 11 , wherein the package comprises one of a thermoplastic resin, a thermosetting resin and a ceramic.

14. The light-emitting device according to claim 1 , wherein the resin layer comprises a sealing portion comprising one of a thermosetting resin, an epoxy resin, a silicone resin and an inorganic material.

15. The light-emitting device according to claim 1 , wherein the heat-conductive particles are uniformly dispersed in a lower portion of the resin layer, which is between the light-emitting element and the phosphor layer.

16. The light-emitting device according to claim 1 , wherein the phosphor layer comprises plural phosphor particles including at least one member selected from a group consisting of BaMgAl 10 O 17 :Eu 2+ , Y 3 Al 5 O 12 :Ce 3+ , (Ba, Sr) 2 SiO 4 :Eu 2+ , Ca(Si, Al) 12 (O,N) 16 :Eu 2+ , SrSi 2 O 2 N 2 :Eu 2+ , CaAlSiN 3 :Eu 2+ , and K 2 SiF 6 :Mn 4+ .

17. A light-emitting device, comprising:
a package;
a lead formed on the package;
a light-emitting element formed on the package and electrically connected to the lead;
a sealing member formed in the package on the light-emitting element, the sealing member comprising:
a lower portion contacting the light-emitting element and comprising a plurality of the heat-conductive particles including a thermal conductivity of not less than 100 W/mK and an electrical insulator property or a semiconductor property;
and an upper portion formed on and contacting the lower portion and comprising a plurality of phosphor particles, the heat-conductive particles conducting heat generated by the plurality of phosphor particles to the lead for dissipating the heat,

wherein the package and the sealing member comprise a base material,
wherein the base material further comprises a recessed portion and white pigment particles, and
wherein the light-emitting element is mounted on a bottom surface of the recessed portion.

18. The light-emitting device according to claim 1 , wherein the resin layer comprises a portion formed on a side of the light-emitting element and extending from an upper surface of the light-emitting element to an upper surface of the conductor layer, and the heat-conductive particles are dispersed in the portion of the resin layer.

19. The light-emitting device according to claim 1 , wherein the conductor layer comprises a pair of leads which protrude outward from a side surface of the package and dissipate heat generated by the plurality of phosphor particles through the package.

Assignees

• Toyoda Gosei Kk

Inventors

• Tsuchiya Yosuke
• Tajima Hiroyuki
• Shimonishi Shota
• Sengoku Akira

Classifications

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10H20/8512

  Wavelength conversion materials · CPC title

• H10H20/8583 Primary

  not being in contact with the bodies · CPC title

• H01L33/644

  Electricity · mapped topic

• F21V29/004 Primary

  Mechanical Engineering · mapped topic