Fluid-suspended microcomponent harvest, distribution, and reclamation

Patent metadata

Field	Value
Publication number	US-10242977-B2
Application number	US-201715838536-A
Country	US
Kind code	B2
Filing date	Dec 12, 2017
Priority date	Oct 31, 2014
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

Fluid-suspended microcomponent management systems and methods are provided. The method provides a first reservoir containing a first solution and a magnetic collection head. A plurality of magnetically polarized microcomponents is suspended in the first solution, where each microcomponent has a maximum cross-section of 150 micrometers (μm) and a maximum mass of 1 microgram. A magnetic field is induced in the collection head and the microcomponents are exposed to the magnetic field. A plurality of microcomponents becomes fixed in position on a collection surface in response to the magnetic field. In one aspect, the step of exposing the microcomponents to the magnetic field includes immersing the collection head in the first reservoir. As a result, the plurality of microcomponents is collected on a surface of the collection head. Alternatively, the step of fixing the plurality of microcomponents in position includes fixing the microcomponents in position on the collection surface sidewall.

First claim

We claim:

1. A fluid-suspended microcomponent management method, the method comprising:
providing a first reservoir containing a first solution;
providing a magnetic collection head;
suspending a plurality of magnetically polarized microcomponents in the first solution, where each microcomponent has a maximum cross-section of 150 micrometers (μm), a maximum mass of 1 microgram, a planar soft ferromagnetic layer thickness in a range of 50 to 2000 nanometers (nm), and a magnetic polarization selected from the group consisting of aligned in parallel with the soft ferromagnetic layer and orthogonal to the soft ferromagnetic layer;
inducing a magnetic field in the collection head;
exposing the microcomponents to the magnetic field; and,
fixing a plurality of microcomponents in position on a collection surface in response to the magnetic field.

2. The method of claim 1 wherein exposing the microcomponents to the magnetic field includes immersing an electromagnetic collection head in the first reservoir; and,
wherein fixing the plurality of microcomponents in position includes collecting the plurality of microcomponents on a surface of the collection head.

3. The method of claim 2 wherein providing the electromagnetic collection head includes providing the electromagnetic collection head with a proximal end bottom surface and a shear break wall formed around a perimeter of the proximal end bottom surface; and,
wherein fixing the plurality of microcomponents in position includes collecting the plurality of microcomponents on the proximal end bottom surface within the perimeter formed by the shear break wall.

4. The method of claim 2 further comprising:
subsequent to collecting the plurality of microcomponents on the collection head surface, transferring the collection head from the first reservoir to a second reservoir containing a second solution;
interrupting the magnetic field; and,
suspending the microcomponents in the second solution in response to interrupting the magnetic field.

5. The method of claim 4 wherein interrupting the magnetic field includes an action selected from the group consisting of canceling the magnetic field, reversing the polarity of the magnetic field, and selectively de-energizing the magnetic field by using an oscillating magnetic field having a first frequency, first amplitude, and first duty cycle.

6. The method of claim 2 wherein providing the first reservoir includes providing the first reservoir with a substrate submerged in the first solution, having a plurality of microcomponent wells formed in a substrate surface;
the method further comprising:
prior to collecting the plurality of microcomponents, performing a solution-based assembly process to seat microcomponents in the wells;
accumulating unseated microcomponents in the first reservoir; and,
wherein collecting the plurality of microcomponents on the collection head surface includes collecting the unseated microcomponents using the magnetic field.

7. The method of claim 1 wherein collecting the microcomponents on the collection surface includes collecting the soft ferromagnetic layers of the microcomponents in an orientation selected from a group consisting of parallel with or orthogonal to a planar collection surface.

8. The method of claim 7 wherein orienting the microcomponents includes forming an arrangement of microcomponents on the collection surface selected from the group consisting of a sub-layer, made up of microcomponents with soft ferromagnetic layers having a parallel magnetic polarization, or multiple layers, made up of microcomponents with soft ferromagnetic layers having an orthogonal magnetic polarization.

9. The method of claim 1 wherein providing the first reservoir includes providing the first reservoir containing the first solution with contaminants;
the method further comprising:
rinsing the collection surface with a third solution to remove the contaminants.

10. The method of claim 9 further comprising:
simultaneous with rinsing the collection surface, applying a force to the collection surface, selected from the group consisting of vibration and magnetic field oscillation, to remove the contaminants.

11. The method of claim 1 wherein providing the first reservoir includes providing the first reservoir with a collection surface sidewall; and,
wherein fixing the plurality of microcomponents in position includes locating the magnetic collection head adjacent an exterior of the collection surface sidewall and fixing the microcomponents in position on the collection surface sidewall.

12. The method of claim 1 wherein providing the first reservoir containing the first solution includes:
providing a first reservoir with an inlet port and an outlet port; and,
the method further comprising:
introducing a solution to the first reservoir selected from the group consisting of the first solution, a second solution, and the first solution followed by the second solution.

13. The method of claim 12 further comprising:
draining the first reservoir of solution; and,
exposing the microcomponents fixed on the collection surface to an environment selected from the group consisting of an ambient air, vacuum, and oxygen plasma.

14. The method of claim 1 wherein providing the first reservoir containing the first solution includes providing a first solution selected from the group consisting of alcohols, ketones, alkanes, organic acids, and water.

15. A system for the distribution of magnetically polarized microcomponents, the system comprising:
magnetically polarized microcomponents, each microcomponent has a maximum cross-section of 150 micrometers (μm) and a maximum mass of 1 microgram;
a reservoir containing a solution, and comprising an inlet port to supply solution at a controlled rate and volume, and an outlet port to drain solution;
a magnetic collection head with a proximal end, a distal end, and a surface to enable the magnetic capture and release of the microcomponents in the solution; and,
wherein the solution is capable of creating shearing forces on magnetically captured microcomponents to remove weakly attached microcomponents and debris.

16. The system of claim 15 further comprising:
a gantry, with an arm attached to the distal end of the electromagnetic collection head, capable of moving the magnetic collection head in horizontal and vertical directions.

17. The system of claim 16 further comprising:
a substrate submerged in the solution, having a plurality of microcomponent wells formed in a substrate surface;
wherein the magnetic collection head is an electromagnetic collection head immersible in the solution and capable of an action selected from the group consisting of the release of magnetically captured microcomponents over the substrate surface for assembly in the substrate wells and the capture of microcomponents unseated in the substrate wells.

18. The system of claim 16 wherein the gantry includes a rotating member connecting the arm of the gantry.

19. The system of claim 16 wherein the gantry includes a vibrational actuator.

20. The system of claim 19 wherein the electromagnetic collection head bottom surface is planar and the shear break wall has a height in the range of 3 to 10,000 microns.

21. The system of claim 16 wherein the magnetic collection head proximal end includes a bottom surface and a shear break wall formed around a perimeter of the proximal end bottom surface.

22. The system of claim 1

Assignees

• Elux Inc

Inventors

• Sasaki Kenji
• Schuele Paul J

Classifications

• H10W72/07178

  Means for aligning · CPC title

• H10W72/07173

  Means for moving chips, wafers or other parts, e.g. conveyor belts · CPC title

• H10W72/0198

  batch processes · CPC title

• H10W90/00 Primary

  Package configurations · CPC title

• H01L25/50 Primary

  Electricity · mapped topic