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

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.

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