Method for fabricating nanoporous polymer thin film and corresponding method for fabricating nanoporous thin film

Patent metadata

Field	Value
Publication number	US-11059205-B2
Application number	US-201816104190-A
Country	US
Kind code	B2
Filing date	Aug 17, 2018
Priority date	Feb 21, 2018
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

A method for fabricating nanoporous polymer thin film includes steps as follows. A polymer thin film is provided, wherein a polymer solution including a polymer is coated on a substrate to form the polymer thin film. A swelling and annealing process is provided, wherein the polymer thin film is disposed inside a chamber with a vapor of a first solvent, the polymer thin film is swollen and annealed to form a swollen polymer thin film, and the swollen polymer thin film includes the polymer and the first solvent. A freezing process is provided, wherein the swollen polymer thin film is cooled to a temperature less than or equal to a crystallization temperature of the first solvent to crystallize the first solvent. A first solvent removing process is provided, wherein the first solvent is removed with a second solvent, such that a nanoporous polymer thin film is obtained.

First claim

What is claimed is:

1. A method for fabricating nanoporous polymer thin film, the method comprising:
providing a polymer thin film, wherein a polymer solution comprising a polymer is coated on a substrate to form the polymer thin film;
providing a swelling and annealing process, wherein the polymer thin film is kept inside a chamber with a vapor of a first solvent, the polymer thin film is swollen and annealed to form a swollen polymer thin film, and the swollen polymer thin film comprises the polymer and the first solvent;
providing a freezing process, wherein the swollen polymer thin film is cooled to a temperature less than or equal to a crystallization temperature of the first solvent to crystallize the first solvent; and
providing a first solvent removing process, wherein the first solvent is removed with a second solvent, such that a nanoporous polymer thin film is obtained.

2. The method of claim 1 , wherein the polymer is polystyrene, the first solvent is N,N-dimethylformamide, and the second solvent is methanol.

3. The method of claim 1 , wherein in the swelling and annealing process, a gas is used for adjusting a mole fraction of the vapor of the first solvent in the chamber to change a weight percentage of the first solvent in the swollen polymer thin film.

4. The method of claim 3 , wherein the weight percentage of the first solvent in the swollen polymer thin film is greater than or equal to 6%.

5. The method of claim 3 , wherein the gas is nitrogen.

6. The method of claim 1 , wherein a processing time of the swelling and annealing process is in a range of 5 minutes to 60 minutes.

7. The method of claim 1 , wherein in the freezing process, liquid nitrogen is used to cool the swollen polymer thin film.

8. A method for fabricating nanoporous thin film, the method comprising:
providing a template, wherein the template comprises a nanoporous polymer thin film fabricated by the method of claim 1 ;
providing a filling process, wherein a mixture film is fabricated, the mixture film comprises a first material and the nanoporous polymer thin film, and the first material is filled in a plurality of pores of the nanoporous polymer thin film; and
providing a template removing process, wherein the nanoporous polymer thin film is removed to form a nanoporous thin film, and the nanoporous thin film is composed of the first material.

9. The method of claim 8 , wherein the first material is a metal, or a ceramic.

10. The method of claim 8 , wherein the first material is SiO 2 , TiO 2 or nickel.

Assignees

• Univ Nat Tsing Hua

Inventors

• Ho Rong-Ming
• Krishnan Mohan Raj
• Siddique Suhail Kizhakkeveettil
• Chien Yu-Cheng

Classifications

• B29C41/003

  characterised by the choice of material · CPC title

• B29L2007/008

  Wide strips, e.g. films, webs · CPC title

• C08J7/02

  with solvents, e.g. swelling agents · CPC title

• C23C18/1644

  porous substrates · CPC title

• C23C18/1216

  Metal oxides (C23C18/1212 takes precedence) · CPC title