Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Directed Assembly of Block Copolymers for Defect-Free Nanofabrication

블록공중합체 자기조립제어를 통한 무결함 나노구조제작

  • Shin, Dong-Ok (Department of Materials Science & Engineering, KAIST) ;
  • Jeong, Seong-Jun (Department of Materials Science & Engineering, KAIST) ;
  • Kim, Bong-Hoon (Department of Materials Science & Engineering, KAIST) ;
  • Lee, Hyung-Min (Department of Materials Science & Engineering, KAIST) ;
  • Park, Seung-Hak (Department of Materials Science & Engineering, KAIST) ;
  • Xia, Guodong (Department of Materials Science & Engineering, KAIST) ;
  • Nghiem, Quoc Dat (Department of Materials Science & Engineering, KAIST) ;
  • Kim, Sang-Ouk (Department of Materials Science & Engineering, KAIST)
  • Received : 2007.09.28
  • Accepted : 2007.09.29
  • Published : 2008.02.28
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Abstract

Block copolymers spontaneously assemble into various nanoscale structures such as spheres, cylinders, and lamellar structures according to the relative volumn ratio of each macromolecular block and their overall molecular weights. The self-assembled structures of block copolymer have been extensively investigated for the applications such as nanocomposites, photonic crystals, nanowires, magnetic-storage media, flash memory devices. However, the naturally formed nanostructures of block copolymers contain a high density of defects such that the practical applications for nanoscale devices have been limited. For the practical application of block copolymer nanostructures, a robust process to direct the assembly of block copolymers in thin film geometry is required to be established. To exploit self-assembly of block copolymer for the nanotechnology, it is indispensible to fabricate defect-free self-assembled nanostructure over an arbitrarily large area.

블록공중합체(block copolymer)는 각 고분자 블록의 상대적인 조성비와 분자량에 따라 구, 실린더, 라멜라 등의 다양한 자기조립 나노구조를 형성하는 것으로 알려져 있다. 최근에는 블록공중합체의 자기조립 나노구조를 이용하여 나노복합재료, 포토닉 크리스탈, 나노선, 자기저장매체, 플래시 메모리 소자 등에 적용하려는 연구들이 활발히 진행되고 있다. 그러나 자연적으로 형성되는 블록공중합체 나노구조는 수많은 결함구조들을 포함하고 있어 실제 소자 적용에 큰 걸림돌이 되고 있다. 블록공중합체 나노구조의 실제적인 응용을 위해서는 박막상태의 시료 내에서 나노구조의 배향과 배열을 원하는 형태로 조절할 수 있는 공정의 확립이 선행되어야 한다. 즉, 블록공중합체의 자기조립을 나노기술분야에 적용하기 위해서는 대면적으로 완벽히 제어된 블록공중합체 나노구조를 구현하는 것이 필요하다.

Keywords

References

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