Guided template based electrokinetic microassembly (TEA)

Patent metadata

Field	Value
Publication number	US-11840769-B2
Application number	US-202117314708-A
Country	US
Kind code	B2
Filing date	May 7, 2021
Priority date	May 8, 2020
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

The present invention is directed to devices and methods for assembling particulates through the use of non-contact electrokinetic forces applied to polymeric, organic, non-organic, and metallic micro- and nano-particulates in an aqueous solution. The present invention features an electrode comprising a conductive substrate with a layer of photosensitive polymer disposed on it with a plurality of windows etched into the layer. The plurality of windows expose certain portions of the conductive substrate. Applying electric signals to the conductive substrate (e.g. by a function generator) causes materials to attract to only the exposed portions of the conductive substrate. The materials may comprise a plurality of organic, non-organic, and metallic micro- and nano-particulates disposed in an aqueous solution.

First claim

What is claimed is:

1. A system for assembling particulates through the use of electrokinetic means, the system comprising:
a. a conductive substrate ( 10 ) comprising a plurality of electrodes disposed side-by-side, each electrode comprising;
a layer of photosensitive polymer ( 20 ) disposed on top of each electrode;
wherein each layer of photosensitive polymer ( 20 ) is patterned with a plurality of windows ( 25 ) exposing the electrode underneath;
wherein, for each electrode, a bottom of each window of the plurality of windows ( 25 ) is made up entirely of the electrode;

c. a solution comprising a plurality of particulates and contacting the conductive substrate; and
d. a function generator ( 30 ) configured to apply a non-uniform AC signal to the plurality of electrodes such that the non-uniform AC signal causes the plurality of particulates in the solution to move and attach to the plurality of electrodes through the plurality of windows ( 25 ).

2. The system of claim 1 , wherein the AC signal is configured to cause electroosmosis or dielectrophoresis.

3. The system of claim 2 , wherein the system is configured to use a combination of electroosmosis and dielectrophoresis to guide the plurality of particles to the plurality of electrodes.

4. The system of claim 1 , wherein the particulates are microparticulates, nanoparticulates, or a combination thereof.

5. The system of claim 1 , wherein the particulates are organic particulates, non-organic particulates, metallic particulates, or a combination thereof.

6. The system of claim 1 , wherein the system is configured to sort the plurality of particulates based on size, shape, density, conductivity, material composition, or permeability.

7. A method for fabricating an electrode array ( 100 ) used for assembling particulates through the use of electrokinetic means, the method comprising:
a. providing a conductive substrate ( 10 ) comprising a plurality of electrodes disposed side-by-side;
b. spin-coating a layer of photosensitive polymer ( 20 ) on top of each electrode of the plurality of electrodes; and
c. patterning each layer of photosensitive polymer ( 20 ) to form a plurality of windows ( 25 ) in each layer of photosensitive polymer ( 20 ) and expose the electrode underneath;
wherein, for each electrode, a bottom of each window of the plurality of windows ( 25 ) is made up entirely of the electrode;
wherein each electrode ( 100 ) is connected to a function generator ( 30 ), wherein the function generator ( 30 ) is configured to generate non-uniform electric signals to attract particulates in a solution to the plurality of electrodes through the plurality of windows ( 25 ).

8. The method of claim 7 further comprising soft baking each layer of photosensitive polymer ( 20 ) after spin-coating it onto the electrode.

9. The method of claim 8 further comprising hard baking the conductive substrate ( 10 ) after soft baking each layer of photosensitive polymer ( 20 ).

10. A method for assembling particulates through the use of electrokinetic means, the method comprising:
a. providing a conductive substrate ( 10 ) comprising:
i. a plurality of electrodes disposed side-by-side, each electrode comprising
a layer of photosensitive polymer ( 20 ) disposed on top of each electrode,
wherein each layer of photosensitive polymer ( 20 ) is patterned with a plurality of windows ( 25 ) to expose the electrode underneath;
wherein, for each electrode, a bottom of each window of the plurality of windows ( 25 ) is made up entirely of the electrode;

b. providing an aqueous solution comprising a plurality of particulates and contacting each layer of photosensitive polymer ( 20 ) and each electrode; and
c. applying non-uniform electrical signals to the plurality of electrodes ( 100 ), wherein the electrical signals cause the plurality of particulates to attract towards each electrode exposed by the plurality of windows ( 25 ).

11. The method of claim 10 , wherein the method sorts the particulates by size, shape, density, conductivity, material composition, or permeability.

12. The method of claim 11 , wherein the particulates are guided to each electrode by a combination of electroosmosis and dielectrophoresis.

13. The method of claim 10 , wherein the particulates are microparticulates, nanoparticulates, or a combination thereof.

14. The method of claim 10 , wherein the particulates are organic particulates, non-organic particulates, metallic particulates, or a combination thereof.

15. The method of claim 10 , wherein the electrical signals are applied by a function generator ( 30 ).

16. The method of claim 10 , wherein the method further comprises entrapping the plurality of particulates attracted to each electrode via electropolymerization.

17. The method of claim 10 , wherein the electropolymerization comprises:
a. providing a polymerization solution;
b. mixing the polymerization solution with a particulate suspension;
c. depositing the polymerization solution and the particulate suspension over each electrode;
d. covering each electrode; and
e. applying a non-uniform DC offset to each electrode ( 100 ) to entrap the plurality of particulates in place.

18. The method of claim 17 , wherein the polymerization solution comprises an electropolymerization monomer and an ionic surfactant.

Assignees

• Univ California

Inventors

• Kulinsky Lawrence
• Zhou tuo

Classifications

• C25D1/006 Primary

  Nanostructures, e.g. using aluminium anodic oxidation templates [AAO] · CPC title

• C25D13/18 Primary

  using modulated, pulsed, or reversing current · CPC title

• C25D13/00

  Electrophoretic coating characterised by the process (C25D15/00 takes precedence; compositions for electrophoretic coating C09D5/44) · CPC title

• C25D13/22

  Servicing or operating {apparatus or multistep processes} · CPC title