Systems and methods for particulate removal using polymeric microstructures

Patent metadata

Field	Value
Publication number	US-11001785-B2
Application number	US-201615772274-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Oct 30, 2015
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

Systems and methods for removing particles from a surface of a substrate without damage to the substrate are provided. The disclosed systems/methods use polymeric microstructures, e.g., microfibrils, to remove micrometric and sub-micrometric particles from a substrate surface by establishing interfacial interactions with the particles that effectively debond the particles from the surface of the substrate. The disclosed systems/methods have wide ranging applications, including particle removal in art conservation processes, microelectronic applications, optical applications and any other field that stands to benefit from precise removal of particles/dust from a surface without damage to the surface.

First claim

The invention claimed is:

1. A method for removing materials from a substrate, comprising:
a. providing an assembly including polymeric microstructures that include microstructure heads supported by stems, wherein each microstructure head defines a microfibril tip and a side of the microfibril, wherein the microfibril tip is of lesser diameter than the supporting stem, and wherein the microstructure heads of the polymeric microstructures have diameters of at least 2 μm;
b. contacting the microfibril tips of the assembly with a surface of a substrate in a direction that is normal to the surface of the substrate;
c. removing a plurality of contaminant particles from the surface of the substrate based on contact of the polymeric microstructures with the contaminant particles, said removal being in a direction that is normal to the surface of the substrate;
wherein removal of the plurality of contaminant particles from the surface of the substrate includes initially associating a first contaminant particle with the microfibril tip and subsequently moving the first contaminant particle to the side of the microfibril based on contact of the microfibril tip with one or more additional contaminant particles from among the plurality of contaminant particles.

2. The method of claim 1 , wherein the plurality of contaminant particles are removed from the surface of the substrate without damage to the surface of the substrate.

3. The method of claim 1 , wherein the plurality of contaminant particles include at least one of micrometric and sub-micrometric particles.

4. The method of claim 1 , wherein the plurality of contaminant particles are removed from the surface of the substrate by establishing interfacial interactions between the plurality of contaminant particles and the polymeric microstructures.

5. The method of claim 4 , wherein the interfacial interactions are sufficiently strong to separate the plurality of contaminant particles from the surface of the substrate.

6. The method of claim 1 , wherein the substrate has utility in one or more of the following fields: microelectronics, aerospace, optics, xerography, medical and art applications.

7. The method of claim 1 , wherein the assembly is formed, in whole or in part, from an elastic and low-surface energy polymeric material.

8. The method of claim 1 , wherein the polymeric microstructures establish intimate contact with both the plurality of contaminant particles and the surface of the substrate.

9. The method of claim 8 , wherein the intimate contact between the polymeric microstructures and the surface of the substrate imparts essentially no physical effect to the surface of the substrate.

10. The method of claim 1 , wherein the plurality of polymeric microstructures define spaces or openings between individual polymeric microstructures, and wherein the movement of the first contaminant particle to the side of the microfibril is effective to position the first contaminant particle in a space or opening defined between individual polymeric microstructures.

11. The method of claim 1 , wherein the movement of the first contaminant particle to the side of the polymeric microfibril reduces damage to the surface of the substrate based on contact between the plurality of contaminant particles associated with the polymeric microstructures and the surface of the substrate.

12. The method of claim 1 , wherein the movement of the first contaminant particle to the side of the polymeric microfibril increases contaminant particle removal by allowing the polymeric microstructures to remove the one or more additional contaminant particles from the surface of the substrate.

13. The method of claim 1 , wherein the polymeric microstructures are fabricated from polydimethylsiloxane.

14. The method of claim 1 , wherein the adhesion force between the polymeric microstructures and the plurality of contaminant particles is greater than the adhesion force between the plurality of contaminant particles and the surface of the substrate.

15. The method of claim 14 , wherein the adhesion force between the polymeric microstructures and the plurality of contaminant particles is at least about five (5) times greater than the adhesion force between the plurality of contaminant particles and the surface of the substrate.

16. The method of claim 1 , wherein the microstructure heads are characterized by diameters that are no more than eight (8) times greater than the diameters of the plurality of contaminant particles.

17. The method of claim 1 , wherein the polymeric microstructures are coated with a material that enhances generation of contact electrification (CE) forces by the polymeric microstructures.

18. The method of claim 17 , wherein the polymeric microstructures are coated with a fluorine-based silane coupling agent.

19. The method of claim 18 , wherein the fluorine-based silane coupling agent is perfluorooctyltrichlorosilane.

20. The method of claim 1 , wherein the assembly contacts the surface of the substrate by way of a tapping action.

21. A method for removing materials from a substrate, comprising:
a. providing an assembly including polymeric microstructures that include microstructure heads supported by stems, wherein the microstructure heads define flat tips and rounded edges, wherein the microstructure heads of the polymeric microstructures have diameters of at least 2 μm;
b. contacting the flat tips of the assembly with a surface of a substrate in a direction that is normal to the surface of the substrate;
c. removing a plurality of contaminant particles from the surface of the substrate based on contact of the polymeric microstructures with the contaminant particles, said removal being in a direction that is normal to the surface of the substrate;
wherein removal of the plurality of contaminant particles from the surface of the substrate includes initially associating a first contaminant particle with the flat tip of the microstructure head and subsequently moving the first contaminant particle to a side of the microstructure head based on contact of the flat tip with one or more additional contaminant particles from among the plurality of contaminant particles.

22. The method of claim 1 , wherein the microstructure heads of the polymeric microstructures have diameters of between 2 μm and 50 μm.

23. The method of claim 21 , wherein the microstructure heads of the polymeric microstructures have diameters of between 2 μm and 50 μm.

Assignees

• Univ Yale

Inventors

• Izadi Hadi
• Vanderlick T Kyle

Classifications

• H10P70/00

  Cleaning of wafers, substrates or parts of devices · CPC title

• H10P72/0406

  for cleaning followed by drying, rinsing, stripping, blasting or the like · CPC title

• B08B1/10

  characterised by the type of cleaning tool · CPC title

• B60J7/141

  for covering load areas, e.g. for pick-up trucks · CPC title

• C11D3/37 Primary

  Polymers {(polymeric surface-active agents C11D1/008; polysaccharides C11D3/222)} · CPC title