Light-emitting diode (LED) with amorphous fluoropolymer encapsulant and lens

• US 6,921,929 B2
• Filed: 06/27/2003
• Issued: 07/26/2005
• Est. Priority Date: 06/27/2003
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: LeBoeuf, Steven Francis, Weaver, Stanton Earl, Buckley, Donald Joseph Jr.
• Primary Examiner(s): Nelms, David
• Assistant Examiner(s): TRAN, LONG K
• Application Number:
  US10/609,040
• Publication Number:
  US 20050006651A1
• Time in Patent Office: 760 Days
• Field of Search: 257/100, 257/98, 313/512, 313/501, 313/502, 313/503
• US Class Current: 257/100
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]

Abstract

A lens and encapsulant made of an amorphous fluoropolymer for a light-emitting diode (LED) or diode laser, such as an ultraviolet (UV) LED (UVLED). A semiconductor diode die (114) is formed by growing a diode (110) on a substrate layer (115) such as sapphire. The diode die (114) is flipped so that it emits light (160, 365) through the face (150) of the layer (115). An amorphous fluoropolymer encapsulant encapsulates the emitting face of the diode die (114), and may be shaped as a lens to form an integral encapsulant/lens. Or, a lens (230, 340) of amorphous fluoropolymer may be joined to the encapsulant (220). Additional joined or separate lenses (350) may also be used. The encapsulant/lens is transmissive to UV light as well as infrared light. Encapsulating methods are also provided.

Claims

1. A light-emitting device, comprising:

a semiconductor diode die that emits light through at least one face thereof; and

an encapsulant that at least partially encapsulates the semiconductor diode die, the encapsulant including at least a portion adjacent the face that comprises an amorphous fluoropolymer.

2. The light-emitting device of claim 1, wherein:

the portion of the encapsulant adjacent the face is shaped to form at least a portion of a lens for directing the light emitted through the face.

3. The light-emitting device of claim 1, wherein:

the portion of the encapsulant adjacent the face comprises a lens for directing the light emitted through the face.

4. The light-emitting device of claim 1, wherein:

the semiconductor diode die comprises a flip chip grown on a substrate that forms the face.

5. The light-emitting device of claim 4, wherein:

the substrate comprises sapphire.

6. The light-emitting device of claim 1, wherein:

the encapsulant is injection molded.

7. The light-emitting device of claim 1, further comprising:

a lens comprising an amorphous fluoropolymer, joined to the encapsulant, for directing the light emitted through the face.

8. The light-emitting device of claim 1, wherein:

the semiconductor diode die comprises a light-emitting diode die.

9. The light-emitting device of claim 1, wherein:

the semiconductor diode die comprises a laser diode die.

10. The light-emitting device of claim 1, wherein:

the emitted light comprises ultraviolet light.

11. The light-emitting device of claim 1, wherein:

the emitted light comprises infrared light.

12. The light-emitting device of claim 1, wherein:

the portion adjacent the face substantially consists of amorphous fluoropolymer.

13. The light-emitting device of claim 1, wherein:

the encapsulant substantially consists of amorphous fluoropolymer.

14. A light-emitting device, comprising:

a semiconductor diode die that emits light through at least one face thereof; and

an integral encapsulant and lens comprising an amorphous fluoropolymer that encapsulates at least the face and directs the light emitted through the face.

15. A light-emitting device, comprising:

a semiconductor diode die that emits light through at least one face thereof;

an encapsulant comprising an amorphous fluoropolymer that encapsulates at least the face; and

at least one lens comprising an amorphous fluoropolymer joined to the encapsulant for directing the light emitted through the face.