Wavelength-converting casting composition and light-emitting semiconductor component

• US 8,071,996 B2
• Filed: 03/25/2010
• Issued: 12/06/2011
• Est. Priority Date: 09/20/1996
• Status: Expired due to Fees

• Current Assignee: OSRAM GmbH (Ams-Osram AG)
• Original Assignee: OSRAM GmbH (Ams-Osram AG)
• Inventors: Höhn, Klaus, Debray, Alexandra, Schlotter, Peter, Schmidt, Ralf, Schneider, Jürgen
• Primary Examiner(s): Tran, Minh-Loan T
• Application Number:
  US12/731,450
• Publication Number:
  US 20100176344A1
• Time in Patent Office: 621 Days
• Field of Search: 257/98, 257/99, 257/100, 257/E33.059, 257/E33.061, 257/E33.074, 313/502, 313/503
• US Class Current: 257/98
• 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. Light emitting semiconductor component comprising:

a semiconductor body configured to emit electromagnetic radiation in a first wavelength range comprising a blue spectral range, wherein the first wavelength range comprises an intensity maximum at a wavelength between 420 nm and 460 nm;

a layer provided on the semiconductor body and comprising a wavelength-converting casting composition for converting at least some of the radiation in the first wavelength range to radiation in a second wavelength range,

wherein the casting composition comprises luminous substance pigments selected from the group consisting of garnets doped with rare earths, thiogallates doped with rare earths, aluminates doped with rare earths and orthosilicates doped with rare earths, and

wherein the luminous substance pigments having grain sizes ≦

20 μ

m and a median diameter ≦

5 μ

m, wherein 50% of the pigments have a gain diameter greater than said median diameter and 50% of the pigments have a grain diameter less than said median diameter.

2. The light emitting semiconductor component of claim 1, wherein the luminous substance pigments comprise Ce-doped garnet material.

3. The light emitting semiconductor component of claim 1, wherein the luminous substance pigments comprise YAG:

Ce material.

4. The light emitting semiconductor component of claim 1, wherein the iron content in the casting composition is ≦

20 ppm.

5. The light emitting semiconductor component of claim 1, wherein the luminous substance pigments are configured to convert the electromagnetic radiation from the first wavelength range to a relatively longer wavelength.

6. The light emitting semiconductor component of claim 1, wherein the casting composition further comprises light-scattering particles.

7. The light emitting semiconductor component of claim 1, wherein the intensity maximum is at 430 nm or 450 nm.

8. The light emitting semiconductor component of claim 1, wherein at least some of the radiation in the first wavelength range is not converted by the wavelength converting casting composition and mixes with the converted radiation in the second wavelength range to produce a mixed color electromagnetic radiation output for the component.

9. The light emitting semiconductor component of claim 8, wherein the mixed color electromagnetic radiation output appears as white light.

10. The light emitting semiconductor component of claim 9, wherein the radiation in the first wavelength range which is not converted comprises blue and the second wavelength range comprises yellow, which mix to produce the appearance of the white light.

11. The light emitting semiconductor component of claim 9, wherein the radiation in the first wavelength range which is not converted comprises blue and the second wavelength range comprises green and red, all of which mix to produce the appearance of the white light.

12. The light emitting semiconductor component of claim 1, further comprising a housing with a recess, and wherein the semiconductor body is positioned within the recess.

13. The light emitting semiconductor component of claim 12, wherein the encapsulation seals the semiconductor body in the recess of the housing.

14. The light emitting semiconductor component of claim 1, wherein the median diameter of the luminous substance pigments is between 1 and 2 micrometers.

15. The light emitting semiconductor component of claim 1, further comprising an encapsulation covering the semiconductor body and the layer.

16. The light emitting semiconductor component of claim 15, wherein the encapsulation comprises a transparent epoxy casting resin.