LIGHT EMITTING DIODE DEVICE AND METHOD FOR PRODUCTION THEREOF CONTAINING CONVERSION MATERIAL CHEMISTRY

• US 20170025587A1
• Filed: 08/23/2016
• Published: 01/26/2017
• Est. Priority Date: 02/03/2012
• Status: Active Grant

• Current Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Original Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Inventors: Evans, Thomas L., Hein, Christopher Luke
• Granted Patent: US 9,711,695 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 33/483 Containers
• CPC Class Codes: H01L 33/501 characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/502 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: H01L 33/56 Materials, e.g. epoxy or silicone resin

Abstract

In one embodiment, a device can comprise: a light emitting diode located in a housing. The housing is formed from a polymer composition comprising: a polymer material, wherein the polymer material comprises at least one of polyolefins, polyesters, cyanoacrylate, cellulose triacetate, ethyl vinyl acetate, propyl vinyl acetate, polyvinylbutyral, polyvinyl chloride, polycarbonate, polyethylene naphthalate, polyurethane, thermoplastic polyurethane, polyamide, polymethyl methacrylate, polystyrene, cellulose nitrate, and combinations comprising at least one of the foregoing polymer materials; and a coated conversion material wherein the coated conversion material comprises an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength. The coated conversion material can have a coating comprising at least one of a silicone oil and amorphous silica and, after the coated conversion material has been exposed to an excitation source, it can have a luminescence lifetime of less than 10⁻⁴ seconds when the excitation source is removed.

Claims

1. A device, comprising:

a light emitting diode located in a housing, wherein the housing is formed from a polymer composition comprising;

a polymer material, wherein the polymer material comprises at least one of polyolefins, polyesters, cyanoacrylate, cellulose triacetate, ethyl vinyl acetate, propyl vinyl acetate, polyvinylbutyral, polyvinyl chloride, polycarbonate, polyethylene naphthalate, polyurethane, thermoplastic polyurethane, polyamide, polymethyl methacrylate, polystyrene, cellulose nitrate, and combinations comprising at least one of the foregoing polymer materials; and

a coated conversion material wherein the coated conversion material comprises an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength;

wherein the coated conversion material has a coating comprising at least one of a silicone oil and amorphous silica; and

wherein after the coated conversion material has been exposed to an excitation source, the coated conversion material has a luminescence lifetime of less than 10<sup>−

4</sup> seconds when the excitation source is removed.

2. The device of claim 1, wherein the polymeric material further comprises polytetrafluoroethylene.

3. The device of claim 1, wherein the coated conversion material comprises semiconductor nanocrystals.

4. The device of claim 3, wherein the semiconductor nanocrystals are semiconductor nanocrystals of cadmium sulfide mixed with manganese and/or a La₃Si₆N:

Ce³⁺.

5. The device of claim 1, wherein the coated conversion material comprises a rare earth doped red sulfate based conversion material having formula:

(SrM3)S

wherein M3 is selected from at least one of the following Ca, Ba, Mg, and combinations comprising at least one of the foregoing.

6. The device of claim 1, wherein the coated conversion material is a green sulfate based conversion material having formula:

(SrM3)(GaM4)₂S₄;

Eu

wherein M3 is selected from at least one of the following Ca, Ba, Mg, and combinations comprising at least one of the foregoing; and

M4 is selected from at least one of the following Al and In, and combinations comprising at least one of the foregoing.

7. The device of claim 1, wherein the coated conversion material is selected from at least one of the following:

a strontium silicate yellow conversion material;

yttrium aluminum garnet doped with rare earth element;

terbium aluminum garnet doped with a rare earth element;

silicate conversion materials;

nitride conversion materials;

nitrido silicates;

nitride orthosilicate;

oxonitridoaluminosilicates; and

combinations comprising at least one of the foregoing.

8. The device of claim 1, wherein the coated conversion material comprises an Eu²⁺ and/or Dy³⁺ doped conversion material having formula:

M₃MgSi₂O₈

wherein M is selected from at least one of the following Ca, Sr, Ba, and combinations comprising at least one of the foregoing.

9. The device of claim 1, wherein the coated conversion material is a selected from at least one of the following:

combinations of coated yellow conversion material with a coated red conversion material;

combinations of coated green and coated red conversion material;

a semiconductor nanocrystals of cadmium sulfide mixed with manganese; and

combinations comprising at least one of the foregoing.

10. A light emitting device, comprising:

a lighting element located in a housing, wherein the housing is formed from a polymer composition comprising;

a polymer material; and

a coated conversion material comprising semiconductor nanocrystals;

wherein the coated conversion material has a coating comprising at least one of a silicone oil and amorphous silica; and

wherein after the coated conversion material has been exposed to an excitation source, the coated conversion material has a luminescence lifetime of less than 10<sup>−

4</sup> seconds when the excitation source is removed.

11. The light emitting device of claim 10, wherein the polymer material comprises polycarbonate.

12. A light emitting device, comprising:

a lighting element located in a housing, wherein the housing is formed from a polymer composition comprising;

a polymer material comprising polycarbonate; and

a coated conversion material, wherein the coated conversion material comprises an inorganic material that converts radiation of a certain wavelength and re-emits of a different wavelength;

wherein the coated conversion material has a coating comprising at least one of a silicone oil and amorphous silica; and

wherein after the coated conversion material has been exposed to an excitation source, the coated conversion material has a luminescence lifetime of less than 10<sup>−

4</sup> seconds when the excitation source is removed.