Semiconductor light emitting device with fluoropolymer lens

• US 20030230977A1
• Filed: 06/12/2002
• Published: 12/18/2003
• Est. Priority Date: 06/12/2002
• Status: Abandoned Application

• Current Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Original Assignee: Lumileds LLC (Apollo Global Management, Inc.)
• Inventors: Epstein, Howard C.
• Application Number:
  US10/170,882
• Publication Number:
  US 20030230977A1
• Time in Patent Office: Days
• US Class Current: 313/512
• CPC Class Codes: H01L 2224/16145 the bodies being stacked
• CPC Class Codes: H01L 2224/48091 Arched
• 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 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 2924/00014 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 33/58 Optical field-shaping elements

Abstract

A light emitting device includes a lens and a semiconductor light emitting device chip underlying the lens. The lens may be a fluoropolymer material. In some embodiments, the semiconductor light emitting device chip is capable of emitting light having a peak wavelength ranging from green through blue. The clarity of the fluoropolymer lens is essentially unchanged after 500 hours of exposure to 600 mW of light at 85° C. and 60% relative humidity.

Claims

1. A light emitting device comprising:

a lens comprising a fluoropolymer; and

a semiconductor light emitting device chip underlying the lens.

2. The light emitting device of claim 1 wherein the semiconductor light emitting device chip is capable of emitting light having a peak wavelength ranging from green through near ultraviolet.

3. The light emitting device of claim 1 wherein the semiconductor light emitting device chip is capable of emitting light having a peak wavelength ranging from about 570 nm to about 360 nm.

4. The light emitting device of claim 1 wherein the fluoropolymer lens comprises (perfluoroalkoxy) fluoropolymer resin.

5. The light emitting device of claim 1 wherein the fluoropolymer lens comprises fluorinated ethylene propylene, a copolymer of hexafluoropropylene and tetrafluoroethylene.

6. The light emitting device of claim 1 wherein a clarity of the fluoropolymer lens is essentially unchanged after 500 hours of exposure to 600 mW of light having a peak wavelength ranging from green through blue.

7. The light emitting device of claim 6 wherein exposure comprises exposure at a temperature greater than or equal to about 85°

C. and a relative humidity greater than or equal to about 60%.

8. The light emitting device of claim 1 wherein an outside shape of the fluoropolymer lens comprises a dome.

9. The light emitting device of claim 1 wherein a clarity of the fluoropolymer lens is essentially unchanged after 1500 hours of exposure to 75 mW of light having a peak wavelength ranging from green through blue.

10. The light emitting device of claim 1 wherein the semiconductor light emitting device chip comprises a plurality of semiconductor layers having the formula Al_xIn_yGa_zN, where 0≦

x≦

1, 0≦

y≦

1, 0≦

z≦

1, x+y+z=1.

11. The light emitting device of claim 1 further comprising a lead frame connected to the semiconductor light emitting device chip.

12. The light emitting device of claim 11 further comprising a submount between at least a portion of the lead frame and at least a portion of the semiconductor light emitting device chip.

13. The light emitting device of claim 12 further comprising a heat sinking slug connected to the submount.

14. The light emitting device of claim 13 wherein the heat sinking slug comprises a reflector cup.

15. The light emitting device of claim 1 wherein the lens consists totally of a fluoropolymer.

16. The light emitting device of claim 1 wherein the lens is shaped such that a maximum intensity is emitted substantially along an axis perpendicular to the semiconductor light emitting device chip.

17. The light emitting device of claim 1 wherein the lens is shaped such that a maximum in intensity is emitted at angles between about 35°

and about 45°

from an axis perpendicular to the semiconductor light emitting device chip.

18. The light emitting device of claim 1 wherein the lens is shaped such that emission along an axis perpendicular to the semiconductor light emitting device chip is between about 35% and about 75% of a maximum intensity.

19. The light emitting device of claim 1 wherein the lens is shaped such that an intensity of emission at angles greater than about 60°

to an axis perpendicular to the semiconductor light emitting device chip is less than about 10% of a maximum intensity.

20. The light emitting device of claim 1 wherein the semiconductor light emitting device chip is capable of emitting light having a peak wavelength suitable for curing dental adhesives.

21. The light emitting device of claim 1 further comprising a wavelength converting material capable of absorbing first light emitted from the semiconductor light emitting device chip and emitting second light having a wavelength longer than a wavelength of the first light.

22. The light emitting device of claim 21 wherein when the first light and second light are combined, the combined light appears white.

23. The light emitting device of claim 21 wherein the second light appears green.

24. The light emitting device of claim 1 wherein the semiconductor light emitting device chip is capable of emitting light having a peak wavelength ranging from about 360 nm to about 200 nm.

25. The light emitting device of claim 24 wherein the semiconductor light emitting device chip is capable of emitting light having a peak wavelength of about 280 nm.