Heavily phosphor loaded LED packages having higher stability

• US 9,680,067 B2
• Filed: 03/18/2014
• Issued: 06/13/2017
• Est. Priority Date: 03/18/2014
• Status: Active Grant

• Current Assignee: GE Lighting Solutions LLC (Savant Systems, LLC)
• Original Assignee: GE Lighting Solutions LLC (Savant Systems, LLC)
• Inventors: Chowdhury, Ashfaqul Islam, Allen, Gary Robert, Cai, Dengke
• Primary Examiner(s): Arroyo, Teresa M
• Application Number:
  US14/217,831
• Publication Number:
  US 20150270451A1
• Time in Patent Office: 1,183 Days
• Field of Search: 257 98, 257 99, 257100, 257678, 257787, 257788, 257789, 257790, 257791, 257795, 438 27
• CPC Class Codes: C09K 11/617 Silicates
• CPC Class Codes: H01L 23/293 Organic, e.g. plastic
• CPC Class Codes: H01L 23/3135 Double encapsulation or coating and encapsulation
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 33/483 Containers
• CPC Class Codes: H01L 33/501 characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• 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: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

Heavily phosphor loaded LED packages having higher stability and a method for increasing the stability of heavily phosphor loaded LED packages. A silicone overlayer is provided on the phosphor silicone blend layer.

Claims

1. A phosphor-loaded LED package comprising:

an LED;

a first layer comprising a gravitationally settled blend of phosphor and silicone overlaying the LED, wherein the blend comprises a phosphor to silicone weight ratio of at least 20%, and wherein the blend comprises at least K₂SiF₆;

Mn⁴⁺ (PFS) phosphor; and

an overlayer comprising silicone, said overlayer which overlays the first layer, wherein the silicone overlayer has a thickness of about 0.1 mm or greater, and wherein the silicone overlayer is made of the same silicone as in the phosphor silicone blend.

2. The LED package of claim 1, wherein the PFS phosphor in the phosphor silicone blend exhibits sensitivity to ambient moisture.

3. The LED package of claim 1, wherein the phosphor silicone blend further includes BSY phosphor.

4. The LED package of claim 1, wherein the LED consumes low to mid power and the blend comprises a BSY-PFS phosphor.

5. The LED package of claim 1, wherein the phosphor silicone blend layer has a thickness of about 0.2 mm.

6. The LED package of claim 1, wherein the silicone overlayer has a thickness between about 0.1 mm and 0.5 mm.

7. A phosphor-loaded LED package comprising:

an LED;

a first layer comprising a blend of phosphor and silicone overlaying the LED, wherein the blend comprises a phosphor to silicone weight ratio of at least 20%, and wherein the blend comprises at least yttrium aluminum garnet (YAG) and K₂SiF₆;

Mn⁴⁺ (PFS) phosphor; and

an overlayer comprising silicone, said overlayer which overlays the first layer.

8. The phosphor-loaded LED package of claim 7, wherein the silicone overlayer has a thickness of about 0.1 mm or greater.

9. The phosphor-loaded LED package of claim 7, wherein the phosphor silicone blend layer has a thickness of about 0.2 mm.

10. The phosphor-loaded LED package of claim 7, wherein the silicone overlayer has a thickness between about 0.1 mm and 0.5 mm.

11. The phosphor-loaded LED package of claim 7, wherein the silicone overlayer is made of the same silicone as in the phosphor silicone blend.

12. A phosphor-loaded LED package comprising:

an LED;

a first layer comprising a blend of phosphor and silicone overlaying the LED, wherein the blend comprises a phosphor to silicone weight ratio of at least 20%, and wherein the blend comprises at least K₂SiF₆;

Mn⁴⁺ (PFS) phosphor; and

an overlayer comprising silicone, said overlayer which overlays the first layer, wherein the silicone overlayer has a thickness of about 0.1 mm or greater.