Filter apparatus for semiconductor device fabrication process

Patent metadata

Field	Value
Publication number	US-11826709-B2
Application number	US-202117333499-A
Country	US
Kind code	B2
Filing date	May 28, 2021
Priority date	May 28, 2021
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

A filter device includes one or more filter membranes, and a filter housing enclosing the one or more filter membranes. Each of the filter membranes includes a base membrane and a plurality of through holes.

First claim

What is claimed is:

1. A method of manufacturing a filter membrane, the method comprising:
forming a photo resist layer over a substrate;
forming a polymer layer over the photo resist layer;
patterning the polymer layer to form a plurality of through holes in the polymer layer;
removing the polymer layer with the plurality of through holes from the substrate, thereby obtaining the filter membrane; and
forming a coating layer made of a polymer material over the filter membrane to reduce diameters of the through holes, wherein:
the patterning comprises:
placing a hard mask over the polymer layer not to contact the polymer layer and at a distance of 1 μm to 1 mm from the polymer layer, the hard mask including a plurality of through holes and being made of a ceramic material;

etching the polymer layer by plasma passing through the plurality of through holes formed in the hard mask; and
an average diameter of the plurality of through holes after the diameters are reduced is in a range from 5 nm to 50 nm.

2. The method of claim 1 , wherein an aspect ratio of plurality of through holes in the polymer layer is in a range from 2 to 10.

3. The method of claim 1 , wherein the polymer layer includes one or more of PVDF (polyvinylidene fluoride), PFA (polyfluoroalkyl), PAS (polyarylsulfone), PES(polyether sulfone), and PEEK (polyetheretherketone), or derivatives thereof.

4. The method of claim 1 , wherein the polymer material of the coating layer is different from the polymer layer.

5. The method of claim 4 , wherein the polymer material of the coating layer is PTFE (polytetrafluoroethylene).

6. The method of claim 1 , wherein a total number of the plurality of holes per square micron in the polymer layer is in a range from 100 to 600.

7. A method of manufacturing a filter membrane, the method comprising:
forming a photo resist layer over a substrate;
forming a polymer layer over the photo resist layer;
placing a hard mask over the polymer layer not to contact the polymer layer and at a distance of 1 μm to 1 mm from the polymer layer, the hard mask including a plurality of through holes and being made of a ceramic material; and
etching the polymer layer by plasma passing through the plurality of through holes formed in the hard mask, thereby forming a plurality of through holes in the polymer layer; and
removing the polymer layer with the plurality of through holes from the substrate, thereby obtaining the filter membrane.

8. The method of claim 7 , wherein the hard mask is made of ceramic.

9. The method of claim 7 , wherein the hard mask is made of anodic aluminum oxide.

10. The method of claim 7 , wherein the plasma is generated from one or more gases including C 4 F 8 , SF 6 , O 2 or Ar.

11. The method of claim 7 , further comprising attaching a fiber based filter membrane to the filter membrane.

12. The method of claim 11 , wherein the fiber based filter membrane has random hole sizes.

13. A method of manufacturing a filter membrane, the method comprising:
forming a sacrificial layer over a substrate;
forming a polymer layer over the sacrificial layer;
placing a hard mask over the polymer layer not to contact the polymer layer and at a distance of 1 μm to 1 mm from the polymer layer, the hard mask including a plurality of through holes and being made of a ceramic material; and
etching the polymer layer by plasma passing through the plurality of through holes formed in the hard mask, thereby forming a plurality of through holes in the polymer layer; and
removing the polymer layer with the plurality of through holes from the substrate, thereby obtaining the filter membrane.

14. The method of claim 13 , further comprising forming a coating layer made of a polymer material over the filter membrane to reduce diameter of the through holes,
wherein the coating material comprises a polymer.

15. The method of claim 14 , wherein the polymer of the coating material is different from the polymer layer.

16. The method of claim 14 , wherein the polymer of the coating material is a same as the polymer layer.

17. The method of claim 1 , wherein a surface of the hard mask is coated with a coating material.

18. The method of claim 17 , wherein the coating material is silicon oxide or silicon nitride.

19. The method of claim 1 , wherein the polymer layer includes one or more of PFA (polyfluoroalkyl), PAS (polyarylsulfone), PES(polyether sulfone), or derivatives thereof.

20. The method of claim 7 , wherein the polymer layer includes one or more of PFA (polyfluoroalkyl), PAS (polyarylsulfone), PES(polyether sulfone), or derivatives thereof.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Yu Chwen
• Lin En Tian
• Tseng Chih-Chiang
• Chuang Tzu-Sou

Classifications

• H10P72/0402

  Apparatus for fluid treatment (H10P72/0441, H10P72/0448 take precedence) · CPC title

• B01D2325/02

  Details relating to pores or porosity of the membranes · CPC title

• B01D63/08

  Flat membrane modules · CPC title

• B01D69/06

  Flat membranes · CPC title

• B01D67/0034 Primary

  by micromachining techniques, e.g. using masking and etching steps, photolithography · CPC title