III-NITRIDE DOWN-CONVERSION NANOMATERIAL FOR WHITE LEDS

• US 20200135974A1
• Filed: 06/08/2018
• Published: 04/30/2020
• Est. Priority Date: 06/09/2017
• Status: Active Grant

• Current Assignee: University Of Massachusetts
• Original Assignee: University Of Massachusetts
• Inventors: Guo, Wei
• Granted Patent: US 11,257,984 B2
• Time in Patent Office: Days
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/62 containing gallium, indium or thallium
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/502 Wavelength conversion materials

Abstract

A phosphor component that includes a plurality of nanowires absorbing light at one wavelength and emitting light at a longer wavelength, the longer wavelength being from about 495 nm to about 780 nm, each one of the plurality of nanowires being one of a nanowire described by a composition formula of InxGa1-_xN, _x being between about 0.1 to about 0.6 or a GaN nanowire having In_xGa1-_xN discs in a nanowire structure, x being between about 0.1 to about 0.8 and a light emitting device using the phosphor component are disclosed.

Claims

1. A phosphor component comprising a plurality of nanowires absorbing light at one wavelength and emitting light at a longer wavelength, the longer wavelength being from about 495 nm to about 780 nm;

each one of the plurality of nanowires being one of a nanowire described by a composition formula of In_xGa_1-xN, x being between about 0.1 to about 0.8 or a GaN nanowire having In_xGa_1-xN discs in the nanowire structure, x being between about 0.1 to about 0.8.

2. The phosphor component of claim 1 wherein each one of the plurality of nanowires is described by a composition formula of In_xGa_1-xN, x being between about 0.1 to about 0.8.

3. The phosphor component of claim 2 wherein a value of x is varied continuously along a length of each nanowire.

4. The phosphor component of claim 2 wherein the plurality of nanowires comprises a first plurality of nanowires having a value of x from about 0.1 to about 0.5 and a second plurality of nanowires having the value of x from about 0.5 to about 0.6.

5. The phosphor component of claim 1 wherein each nanowire from the plurality of nanowires is not on a common substrate with another nanowire from the plurality of nanowires.

6. The phosphor component of claim 5 wherein said each nanowire is disposed in a binder;

wherein a resulting binding agent dispersion comprises the plurality of nanowires and at least one of a polymer or oligomer binding agent.

8. The phosphor component of claim 1 wherein each nanowire from the plurality of nanowires is disposed on a light emitting structure, the light emitting structure emitting light at a wavelength of less than 495 nm.

9. A light emitting device comprising:

the phosphor component of claim 1; and

a light source emitting light at a wavelength of less than 495 nm.

10. The light emitting device of claim 9 wherein each one of the plurality of nanowires is described by a composition formula of In_xGa_1-xN, x being between about 0.1 to about 0.8;

and wherein a value of x is selected from a value varying in a predetermined range or a value varying continuously along a length of each nanowire.

12. The light emitting device of claim 10 wherein the plurality of nanowires comprises a first plurality of nanowires having a value of x from about 0.10 to about 0.5 on a second plurality of nanowires having the value of x from about 0.5 to about 0.6.

13. The light emitting device of claim 9 wherein each nanowire from the plurality of nanowires is not on a common substrate with another nanowire from the plurality of nanowires.

14. The light emitting device of claim 13 wherein said each nanowire is disposed in a binder;

wherein said each nanowire disposed in a binder is disposed to receive light emanated from the light source.

15. The light emitting device of claim 9 wherein each nanowire from the plurality of nanowires is disposed on the light source.

16. The light emitting device of claim 15 wherein each nanowire from the plurality of nanowires is deposited on the light source.

7. (canceled)

11. (canceled)

17. A method for making a phosphor component, the method comprising:

depositing a plurality of nanowires absorbing light at one wavelength and emitting light at a longer wavelength on a substrate, the longer wavelength being from about 495 nm to about 700 nm, each one of the plurality of nanowires being one of a nanowire described by a composition formula of In_xGa_1-xN, x being between about 0.1 to about 0.6 or a GaN nanowire having In_xGa_1-xN discs in a nanowire structure, x being between about 0.1 to about 0.8;

wherein the plurality of nanowires constitutes the phosphor component.

18. The method of claim 17 wherein each one of the plurality of nanowires is described by a composition formula of In_xGa_1-xN, x being between about 0.1 to about 0.8.

19. The method of claim 17 further comprising:

separating each nanowire from the plurality of nanowires such that said each nanowire from the plurality of nanowires is not on a common substrate with another nanowire from the plurality of nanowires.

20. The method of claim 17 wherein the plurality of nanowires is deposited by one of molecular beam epitaxy, low temperature halide chemical vapor deposition, or metal-Organic Chemical Vapor Deposition.

21. The method of claim 19 wherein separating said each nanowire is performed by at least one of the razor blade cutting, ultrasonic sonication or using a substrate including a sacrificial layer and removing the sacrificial layer.

22. The method of claim 19 further comprising dispersing the plurality of nanowires in a binder;

and disposing the plurality of nanowires dispersed in the binder to receive light from a light source emitting light at a wavelength of less than 495 nm.

23. (canceled)

24. (canceled)