Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Formation of Aluminum Etch Tunnel Pits with Uniform Distribution Using UV-curable Epoxy Mask

UV-감응형 에폭시 마스크를 사용한 균일한 분포의 터널형 알루미늄 에치 피트 형성 연구

  • Park, Changhyun (Department of Chemistry and Chemical Engineering, Inha University) ;
  • Yoo, Hyeonseok (Department of Chemistry and Chemical Engineering, Inha University) ;
  • Lee, Junsu (Department of Chemistry and Chemical Engineering, Inha University) ;
  • Kim, Kyungmin (Department of Chemistry and Chemical Engineering, Inha University) ;
  • Kim, Youngmin (SAMYOUNG S&C CO. LTd.) ;
  • Choi, Jinsub (Department of Chemistry and Chemical Engineering, Inha University) ;
  • Tak, Yongsug (Department of Chemistry and Chemical Engineering, Inha University)
  • Published : 2013.10.31
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Abstract

The high purity Al foil, which has an enlarged surface area by electrochemical etching process, has been used as an anode for an aluminum electrolytic capacitor. Etch pits are randomly distributed on the surface because of the existence of surface irregularities such as impurity and random nucleation of pits. Even though a large surface area was formed on the tunnel-etched Al, its applications to various fields were limited due to non-uniform tunnel morphologies. In this work, the selective electrochemical etching of aluminum was carried out by using a patterned mask fabricated by photolithographic method. The formation of etch pits with uniform distribution has been demonstrated by the optimization of experimental conditions such as current density and etching solution temperature.

고순도의 알루미늄 호일은 전기화학적 에칭을 통해 표면적을 증가시킨 후 전해 커패시터의 양극으로 사용된다. 그러나 산화 피막의 결함 및 에치 피트의 불규칙 생성에 의해 성장된 에치 피트의 분포는 불균일하며 이러한 불균일 형태는 알루미늄 넓은 표면적 분포에도 불구하고 여러 형태의 적용을 어렵게 만든다. 본 연구에서는 알루미늄의 선택적 에칭을 위해 포토리소그래피 방법으로 제작된 패턴 마스크를 사용하여 알루미늄 표면에 균일성을 갖는 보호층을 형성시켰다. 균일한 패턴을 갖는 알루미늄을 용액의 온도 및 전류밀도 등의 조건을 변경하여 실험하였고, 알루미늄 표면에 다양한 크기($2{\sim}5{\mu}m$)의 균일성을 갖는 에치 피트의 형성을 확인할 수 있었다.

Keywords

References

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