APPARATUS AND METHOD FOR THE PRODUCTION OF QUANTUM PARTICLES

• US 20180126464A1
• Filed: 11/09/2016
• Published: 05/10/2018
• Est. Priority Date: 11/09/2016
• Status: Active Grant

• Current Assignee: 6K Incorporated
• Original Assignee: Amastan Technologies LLC
• Inventors: Hadidi, Kamal, Wrobel, Gregory
• Granted Patent: US 10,543,534 B2
• Time in Patent Office: Days
• CPC Class Codes: B22F 1/00 Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
• CPC Class Codes: B22F 1/145 Chemical treatment, e.g. passivation or decarburisation
• CPC Class Codes: B22F 2009/0836 with electric or magnetic field or induction
• CPC Class Codes: B22F 2009/0848 Melting process before atomisation
• CPC Class Codes: B22F 2202/13 Use of plasma
• CPC Class Codes: B22F 2301/30 Low melting point metals, i.e. Zn, Pb, Sn, Cd, In, Ga
• CPC Class Codes: B22F 2302/45 Others, including non-metals
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 2999/00 Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B22F 9/082 atomising using a fluid using centrifugal force B22F9/10
• CPC Class Codes: B22F 9/14 using electric discharge
• CPC Class Codes: B22F 9/16 using chemical processes
• CPC Class Codes: B82B 3/0033 Manufacture or treatment of substrate-free structures, i.e. not connected to any support
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 19/007 Tellurides or selenides of metals C01B19/002 takes precedence
• CPC Class Codes: C01G 9/03 Processes of production using dry methods, e.g. vapour phase processes
• CPC Class Codes: C01P 2004/64 Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C23C 10/08 only one element being diffused
• CPC Class Codes: C23C 26/00 Coating not provided for in groups C23C2/00 - C23C24/00
• CPC Class Codes: Y10S 977/774 : Exhibiting three-dimensional carrier confinement, e.g. quantum dots
• CPC Class Codes: Y10S 977/896 : Chemical synthesis, e.g. chemical bonding or breaking

Abstract

Systems, methods, and devices are disclosed for producing quantum particles (e.g., quantum dots) having a uniform size by vaporization of molten precursor droplets. More particularly, the present technology produces quantum dots by melting or liquefying solid and substantially pure precursor materials followed by production of uniformly sized droplets of molten precursor by use of a droplet maker into a microwave generated plasma torch.

Claims

1. A system for the manufacture of quantum particles from a solid precursor material, the system comprising:

a molten material droplet maker capable of providing substantially uniformly sized droplets of a molten material while maintaining the droplets in a molten state, the molten material formed from the solid precursor material;

a plasma chamber in communication with the droplet maker and disposed to receive a flow of molten droplets from the droplet maker;

at least one inlet for introducing a gas or vapor into the plasma chamber;

an energy source for forming a plasma, the energy source in communication with the plasma chamber and disposed to apply energy to the gas or vapor in the plasma chamber to form the plasma at a location within the plasma chamber to permit the flow of molten droplets to be vaporized to form a quantum particle precursor material; and

a quenching chamber in communication with the plasma chamber and disposed to receive the quantum particle precursor material, the quenching chamber adapted to quench the quantum particle precursor material to inhibit growth and to form the quantum particles from the quantum particle precursor material.

2. The system of claim 1, wherein the substantially uniformly sized droplets of the molten material each has a droplet diameter that is within 50% of predetermined droplet size.

3. The system of claim 2, wherein each droplet has a droplet diameter that is within 10% of a predetermined droplet size.

4. The system of claim 1, wherein the energy source comprises a microwave energy source.

5. The system of claim 4, wherein the microwave energy source has a radiation frequency from about 900 MHz to about 5900 MHz.

6. The system of claim 1, wherein the droplet maker comprises a heating element disposed to maintain the molten material formed from the solid precursor material in the molten state.

7. The system of claim 1, wherein the droplet maker comprises a piezoelectric actuator, a flexible plate, and at least one capillary for delivering molten material.

8. The system of claim 1, further comprising a low-pressure pump, the low-pressure pump in communication with the quenching chamber and disposed to produce low pressure within the quenching chamber.

9. The system of claim 1, wherein the quenching chamber comprises one or more exterior walls and a cooling fluid source, at least one exterior wall comprising a plurality of holes, the plurality of holes disposed to receive a flow of cooling fluid from the cooling fluid source.

10. A method for the manufacture of quantum particles from a solid precursor material, the method comprising:

melting the solid precursor material to create a molten precursor material;

forming droplets of the molten precursor material;

vaporizing the droplets within a plasma to form a plasma treated vapor; and

quenching the plasma treated vapor to form quantum particles.

11. The method of claim 10, further comprising introducing a second vapor comprising a functionalizing material.

12. The method of claim 10, further comprising introducing a second vapor prior to the quenching step, the second vapor comprising an alloying material to form a mixture with the plasma treated vapor.

13. The method of claim 12, wherein the second vapor comprises silane for forming silicon based alloys.

14. The method of claim 10, further comprising generating the plasma, the step of generating the plasma comprising generating microwave radiation, guiding microwave radiation to the plasma chamber using a waveguide, introducing an entrainment gas into the plasma chamber, and igniting the plasma.

15. The method of claim 10, further comprising mixing the molten precursor material prior to forming droplets.

16. The method of claim 10, wherein the vaporizing step occurs in a plasma chamber and the quenching step occurs in a quenching chamber, and a pressure gradient is established such that the quenching chamber is maintained at a lower pressure than the plasma chamber.

17. The method of claim 16, further comprising maintaining the plasma chamber between about 700 to 1100 Torr and maintaining the quenching chamber between about 1 to 100 Torr.

18. The method of claim 10, wherein the step of forming droplets comprises agitating the molten precursor material with a piezoelectric actuator and forcing the molten precursor material through at least one capillary.

19. The method of claim 10, where the quenching step is achieved by causing supersaturation, nucleation, and controlled growth to form the quantum particles.

20. The method of claim 10, wherein the quenching step comprises establishing low pressure in the quenching chamber, the low pressure being sufficient to achieve rapid expansion and condensation of the vapor.

21. The method of claim 10, wherein at least about 50% of precursor material consumed in the method is converted into quantum particles.

22. The method of claim 10, wherein the quenching step comprises creating a controlled gaseous environment in which the plasma treated vapor passes through.

23. The method of claim 22, wherein the controlled gaseous environment includes one or more elemental gases.

24. The method of claim 22, wherein the controlled gaseous environment includes one or more molecular gases.

25. The method of claim 10, wherein the quenching step comprises flowing a cooling fluid proximate the plasma treated vapor.

26. The method of claim 10, wherein the quenching step occurs partially within a plasma chamber and partially within a quenching chamber.

27. The method of claim 10, further comprising a functionalizing step, the functionalizing step comprising providing a functionalizing gas or vapor within the quenching chamber wherein said functionalizing gas or vapor contains a functional group precursor.

28. The method of claim 10, wherein the solid precursor material is a material selected from the group consisting of:

tin, selenium, aluminum, gallium, indium, cadmium, zinc, lead, bismuth, europium, arsenic, iodine, thallium, silver, strontium lithium, barium, and alloys of the same.

29. The method of claim 10, further comprising a filtering or collection step.

30. A method of manufacturing a quantum dot having a core at least partially surrounded by a shell, the method comprising:

melting a core precursor material to create a molten core precursor material;

forming core precursor material droplets from the molten core precursor material;

vaporizing the core precursor material droplets within plasma;

forming quantum dot cores from the vaporized core precursor material droplets;

melting a shell precursor material to create a molten shell precursor material;

forming shell precursor material droplets of the molten shell precursor material;

vaporizing shell precursor material droplets within plasma; and

forming quantum dot shells on the quantum dot cores.