Device and method for emitting output light using group IIB element selenide-based and group IIA element gallium sulfide-based phosphor materials

• US 20050156510A1
• Filed: 01/21/2004
• Published: 07/21/2005
• Est. Priority Date: 01/21/2004
• Status: Abandoned Application

• Current Assignee: Avago Technologies ECBU IP Singapore Pte Limited (Broadcom, Inc.), Phosphortech Corporation
• Original Assignee: Avago Technologies ECBU IP Singapore Pte Limited (Broadcom, Inc.)
• Inventors: Chua, Janet Bee Yin, Summers, Christopher J., Choo, Hwai Peng, Ahmad, Azlida, Menkara, Hisham
• Application Number:
  US10/761,763
• Publication Number:
  US 20050156510A1
• Time in Patent Office: Days
• US Class Current: 313/501
• CPC Class Codes: C09K 11/7731 with alkaline earth metals
• CPC Class Codes: C09K 11/883 with zinc or cadmium
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• 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 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

A device and method for emitting output light utilizes a mixture of Group IIB element Selenide-based phosphor material and Group IIA element Gallium Sulfide-based phosphor material in which the Group IIA element includes Calcium, Strontium and/or Barium to convert some of the original light emitted from a light source of the device to longer wavelength light to change the optical spectrum the output light. Thus, the device and method can be used to produce white color light. The mixture of Group IIB element Selenide-based and Group IIA element Gallium Sulfide-based phosphor materials is included in a wavelength-shifting region optically coupled to the light source, which may be a blue light emitting diode (LED) die.

Claims

1. A device for emitting output light, said device comprising:

a light source that emits first light of a first peak wavelength in a blue wavelength range; and

a wavelength-shifting region optically coupled to said light source to receive said first light, said wavelength-shifting region including Group IIB element Selenide-based phosphor material having a property to convert some of said first light to second light of a second peak wavelength in a red wavelength range, said wavelength-shifting region further including Gallium Sulfide-based phosphor material having a property to convert some of said first light to third light of a third peak wavelength in a green wavelength range, said Gallium Sulfide-based phosphor material including at least one Group IIA element selected from a group consisting of Calcium, Strontium and Barium, said first light, said second light and said third light being components of said output light.

2. The device of claim 1 wherein said Group IIB element Selenide-based phosphor material of said wavelength-shifting region includes Zinc Selenide.

3. The device of claim 2 wherein said Group IIB element Selenide-based phosphor material of said wavelength-shifting region includes said Zinc Selenide activated by at least one element selected from a group consisting of Copper, Chlorine, Fluorine, Bromine and Silver.

4. The device of claim 1 wherein said Group IIB element Selenide-based phosphor material of said wavelength-shifting region includes Cadmium Selenide.

5. The device of claim 1 wherein said Gallium Sulfide-based phosphor material includes Barium Gallium Sulfide activated by a rare metal element.

6. The device of claim 5 wherein said Gallium Sulfide-based phosphor material includes said Barium Gallium Sulfide activated by Europium as defined by the formula:

BaGa₄S₇;

Eu.

7. The device of claim 1 wherein said light source includes a light emitting diode die.

8. A device for emitting output light, said device comprising:

a semiconductor die that emits first light of a first peak wavelength in a blue wavelength range;

a phosphor-containing medium optically coupled to said light source to receive said first light, said phosphor-containing medium including Group IIB element Selenide-based phosphor material having a property to convert some of said first light to second light of a second peak wavelength in a red wavelength range, said phosphor-containing medium further including Gallium Sulfide-based phosphor material having a property to convert some of said first light to third light of a third peak wavelength in a green wavelength range, said Gallium Sulfide-based phosphor material including at least one Group IIA element selected from a group consisting of Calcium, Strontium and Barium, said first light, said second light and said third light being components of said output light.

9. The device of claim 8 wherein said Group IIB element Selenide-based phosphor material of said phosphor-containing medium includes Zinc Selenide.

10. The device of claim 9 wherein said Group IIB element Selenide-based phosphor material of said phosphor-containing medium includes said Zinc Selenide activated by at least one element selected from a group consisting of Copper, Chlorine, Fluorine, Bromine and Silver.

11. The device of claim 8 wherein said Group IIB element Selenide-based phosphor material of said phosphor-containing medium includes Cadmium Selenide.

12. The device of claim 8 wherein said Gallium Sulfide-based phosphor material includes Barium Gallium Sulfide activated by a rare metal element.

13. The device of claim 12 wherein said Gallium Sulfide-based phosphor material includes said Barium Gallium Sulfide activated by Europium as defined by the formula:

BaGa₄S₇;

Eu.

14. The device of claim 8 wherein said semiconductor die is a light emitting diode.

15. A method of emitting output light, said method comprising:

generating first light of a first peak wavelength in a blue wavelength range;

receiving said first light, including converting some of said first light to second light of a second peak wavelength in a red wavelength range using Group IIB element Selenide-based phosphor material and converting some of said first light to third light of a third peak wavelength in a green wavelength range using Gallium Sulfide-based phosphor material, said Gallium Sulfide-based phosphor material including at least one Group IIA element selected from a group consisting of Calcium, Strontium and Barium; and

emitting said first light, said second light and said third light as components of said output light.

16. The method of claim 15 wherein said Group IIB element Selenide-based phosphor material includes Zinc Selenide.

17. The method of claim 16 wherein said Group IIB element Selenide-based phosphor material includes said Zinc Selenide activated by at least one element selected from a group consisting of Copper, Chlorine, Fluorine, Bromine and Silver.

18. The method of claim 15 wherein said Group IIB element Selenide-based phosphor material includes Cadmium Selenide.

19. The method of claim 15 wherein said Gallium Sulfide-based phosphor material includes Barium Gallium Sulfide activated by a rare metal element.

20. The method of claim 19 wherein said Gallium Sulfide-based phosphor material includes said Barium Gallium Sulfide activated by Europium as defined by the formula:

BaGa₄S₇;

Eu.