Wavelength-converting casting composition and light-emitting semiconductor component

• US 20010028053A1
• Filed: 04/25/2001
• Published: 10/11/2001
• Est. Priority Date: 09/20/1996
• Status: Active Grant

• Current Assignee: OSRAM GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Schlotter, Peter, Schmidt, Ralf, Schneider, Jurgen, Debray, Alexandra, Hohn, Klaus
• Granted Patent: US 6,592,780 B2
• Time in Patent Office: Days
• US Class Current: 252/301.36
• CPC Class Codes: C09K 11/7718 with alkaline earth metals
• CPC Class Codes: C09K 11/7746 with alkaline earth metals
• CPC Class Codes: C09K 11/7767 Chalcogenides
• CPC Class Codes: C09K 11/7769 Oxides C09K11/7768 takes precedence
• CPC Class Codes: C09K 11/7774 Aluminates
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/502 : Wavelength conversion materials
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: Y02B 20/00 : Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

The wavelength-converting casting composition is based on a transparent epoxy casting resin with a luminous substance admixed. The composition is used in an electroluminescent component having a body that emits ultraviolet, blue or green light. An inorganic luminous substance pigment powder with luminous substance pigments is dispersed in the transparent epoxy casting resin. The luminous substance is a powder of Ce-doped phosphors and the luminous substance pigments have particle sizes ≦20 μm and a mean grain diameter d₅₀≦5 μm.

Claims

1. A wavelength-converting casting composition, for converting a wavelength of ultraviolet, blue or green light emitted by an electroluminescent component, comprising:

a transparent casting resin;

an inorganic luminous substance pigment powder dispersed in said transparent resin, said pigment powder comprising luminous substance pigments from Ce-doped phosphors; and

said luminous substance pigments having grain sizes ≦

20 μ

m and a mean grain diameter d₅₀≦

5 μ

m.

2. The casting composition according to

claim 1

, wherein said luminous substance pigments are substantially spherical particles.

3. The casting composition according to

claim 1

, wherein said luminous substance pigments are flakelike particles.

4. The casting composition according to

claim 1

, wherein the mean grain diameter d₅₀ of said luminous substance pigments is between one and two micrometers.

5. The casting composition according to

claim 1

, which comprises the following components:

a) epoxy casting resin ≧

60% by weight;

b) luminous substance pigments >

0 and ≦

25% by weight;

c) thixotropic agent >

0 and ≦

10% by weight;

d) mineral diffusor >

0 and ≦

10% by weight;

e) processing adjuvant >

0 and ≦

3% by weight;

f) hydrophobic agent >

0 and ≦

3% by weight; and

g) adhesion promoters >

0 and ≦

2% by weight.

6. The casting composition according to

claim 1

, wherein said Ce-doped phosphors are garnets.

7. The casting composition according to

claim 1

, wherein said Ce-doped phosphors are YAG:

Ce based particles.

8. The casting composition according to

claim 1

, which comprises a content of iron ≦

20 ppm.

9. The casting composition according to

claim 1

, wherein said luminous substance pigments are formed with a silicon coating.

10. A light-emitting semiconductor component, comprising:

a semiconductor body formed of a semiconductor layer sequence and being capable, during an operation of the semiconductor component, of emitting electromagnetic radiation in at least one of an ultraviolet, blue, and green spectral range;

a wavelength-converting casting composition disposed in a vicinity of said semiconductor body, said casting composition being formed of a transparent casting resin and an inorganic luminous substance pigment powder dispersed in said transparent resin, said pigment powder comprising luminous substance pigments from Ce-doped phosphors and having grain sizes ≦

20 μ

m and a mean grain diameter d₅₀≦

5 μ

m;

said luminous substance pigments converting a portion of the radiation originating from the at least one of the ultraviolet, blue and green spectral range into radiation of a higher wavelength, such that the semiconductor component emits mixed radiation including the higher-wavelength radiation and radiation from the at least one of the ultraviolet, blue and green spectral range.

11. The light-emitting semiconductor component according to

claim 10

, wherein said casting composition encloses at least a part of said semiconductor body.

12. The light-emitting semiconductor component according to

claim 10

, wherein said semiconductor body is adapted to emit radiation in a blue spectral range having a maximum luminescence intensity at λ

=430 nm or at λ

=450 nm.

13. The light-emitting semiconductor component according to

claim 10

, which further comprises an opaque base housing having a recess formed therein, said semiconductor body being disposed in said recess and said recess being at least partially filled with said casting composition.

14. The light-emitting semiconductor component according to

claim 10

, wherein said casting composition is provided with various kinds of luminous substance pigments in respect to a host lattice distribution and a type and extent of doping.

15. The light-emitting semiconductor component according to

claim 10

, wherein said semiconductor body is a blue light emitting semiconductor body, and said Ce-doped phosphor comprises types of garnet adapted to shift some of the blue light emitted by said semiconductor body into a yellow spectral range, whereby the semiconductor component emits white light.

16. The light-emitting semiconductor component according to

claim 10

, wherein said semiconductor body is a blue light emitting semiconductor body, and said Ce-doped phosphor shifts some of the blue light emitted by said semiconductor body into a green and red spectral range, whereby the semiconductor component emits white light.