Light emission diode package

• US 20030116769A1
• Filed: 06/18/2002
• Published: 06/26/2003
• Est. Priority Date: 12/24/2001
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Cheon, Jong Pil, Song, Kyung Sub
• Granted Patent: US 6,707,069 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

An LED package, made of ceramic substrates and having a reflective metal plate, is disclosed. This LED package consists of a first ceramic substrate, which has a chip mounting area on its top surface, and is provided with a predetermined conductive pattern formed around the chip mounting area. One or more LED chips are seated on the chip mounting area of the first ceramic substrate, and are connected to the conductive pattern. A second ceramic substrate is mounted on the top surface of the first ceramic substrate and has a cavity at a position corresponding to the chip mounting area. The reflective metal plate is set in the cavity of the second ceramic substrate to surround the LED chips. This LED package effectively controls the luminous intensity of the LED chips and the angular distribution of the luminance. The reflective metal plate also collaterally acts as a heat sink effectively dissipating heat from the LED chips to the surroundings of the LED package.

Claims

1. A light emission diode package, comprising:

a first ceramic substrate having a chip mounting area on a top surface thereof, and provided with a predetermined conductive pattern formed around the chip mounting area;

at least one light emission diode (LED) chip seated on said chip mounting area of the first ceramic substrate, and connected to the conductive pattern;

a second ceramic substrate mounted on said first ceramic substrate and having cavity at a position corresponding to said at least one chip mounting area; and

a reflective plate made of metal and provided in said cavity of the second ceramic substrate so as to surround the LED chip.

2. The light emission diode package according to claim 1, wherein said reflective plate has a cylindrical structure, with a diameter of an upper end thereof being larger than a diameter of a lower end thereof.

3. The light emission diode package according to claim 2, wherein said reflective plate controls an angular distribution of luminance of the LED chip by changing an angle of inclination of a sidewall of said reflective plate, with the inclination of said sidewall being formed by a difference in the diameter between the upper and lower ends of said reflective plate.

4. The light emission diode package according to claim 1, wherein said reflective plate controls luminance of the LED chip by changing a surface area surrounding the LED chip.

5. The light emission diode package according to claim 1, wherein said reflective plate controls luminance of the LED chip by selecting a reflective plate made of metals with different reflectivities.

6. The light emission diode package according to claim 1, wherein said reflective plate is added with a coated layer on an inner surface thereof.

7. The light emission diode package according to claim 6, wherein said coated layer is made of a material selected from the group consisting of Sn, SnPb and Ag.

8. The light emission diode package according to claim 1, wherein said reflective plate is mounted to an upper surface of said second ceramic substrate around an upper edge of said cavity.

9. The light emission diode package according to claim 8, wherein said reflective plate is mounted to the upper surface of the second ceramic substrate using a silicone-based bonding agent having high heat conductivity.

10. The light emission diode package according to claim 1, further comprising a molded insulating part made of a transparent moldable material and airtightly packaging the LED chip, said insulating part being connected to said reflective plate.

11. The light emission diode package according to claim 10, wherein the transparent moldable material of said molded insulating part is selected from the group consisting of epoxy resin and silicone-based resin.

12. The light emission diode package according to claim 1, wherein said reflective plate has a support flange at an upper end thereof, and is rested on an upper surface of said second ceramic substrate at said support flange.

13. The light emission diode package according to claim 12, wherein said support flange is integrally formed along an upper edge of the reflective plate.

14. The light emission diode package according to claim 12, wherein said support flange extends from the upper end of the reflective plate to a predetermined position on the upper surface of the second ceramic substrate, thus effectively dissipating heat from the reflective plate.

15. The light emission diode package according to claim 1, wherein said first ceramic substrate consists of a ceramic substrate part having a heat dissipating hole formed therethrough, and a ceramic sheet covering the heat dissipating hole at an upper surface of said ceramic substrate part, and both the chip mounting area and the conductive pattern are formed on an upper surface of said ceramic sheet.

16. The light emission diode package according to claim 15, wherein said heat dissipating hole of the ceramic substrate part is filled with metal paste.

17. The light emission diode package according to claim 1, wherein the ceramic substrate is made of alumina or SiC.

18. The light emission diode package according to claim 1, wherein said conductive pattern extends to a side surface of said first ceramic substrate.

19. The light emission diode package according to claim 1, wherein said conductive pattern is made of an Ag/Ni/Au layer.

20. The light emission diode package according to claim 1, further comprising a hemispherical lens covering a top of said cavity of the second ceramic substrate.

21. The light emission diode package according to claim 20, wherein said hemispherical lens is made of a polymeric material.