Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
권호 표지
DOI QR코드

DOI QR Code

Formation of Nanoporous TiO2 Thin Films on Si by Anodic Oxidation

양극산화에 의한 나노다공성 TiO2 박막 생성

  • Yoon, Yeo-Jun (Seoul Science High School) ;
  • Kim, Do-Hong (Electronic Materials Center, Korea Institute of Science and Technology) ;
  • Jang, Ho-Won (Electronic Materials Center, Korea Institute of Science and Technology)
  • 윤여준 (서울과학고등학교) ;
  • 김도홍 (한국과학기술연구원 전자재료센터) ;
  • 장호원 (한국과학기술연구원 전자재료센터)
  • Received : 2010.06.18
  • Accepted : 2010732
  • Published : 2010.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

Nanoporous titanium dioxide ($TiO_2$) is very attractive material for various applications due to the high surface to volume ratio. In this study, we have fabricated nanoporous $TiO_2$ thin films on Si by anodic oxidation. 500-nm-thick titanium (Ti) films were deposited on Si by using electron beam evaporation. Nanoporous structures in the Ti films were obtained by anodic oxidization using ethylene glycol electrolytes containing 0.3 wt% $NH_4F$ and 2 vol% $H_2O$ under an applied bias of 5 V. The diameter of nanopores in the Ti films linearly increased with anodization time and the whole Ti layer could become nanoporous after anodizing for 3 hours, resulting in vertically aligned nanotubes with the length of 200~300 nm and the diameter of 50~80 nm. Upon annealing at $600^{\circ}C$ in air, the anodized Ti films were fully crystallized to $TiO_2$ of rutile and anatase phases. We believe that our method to fabricate nanoporous $TiO_2$ films on Si is promising for applications to thin-film gas sensors and thin-film photovoltaics.

Keywords

References

  1. B. O'Regan and M. Gratzel, Nature 353, 737 (1991). https://doi.org/10.1038/353737a0
  2. R. Asahi, T. Morikawa, T. Ohwaki, K. Aoki, and Y. Taga, Science 293, 269 (2001). https://doi.org/10.1126/science.1061051
  3. J. Q. Xi, M. F. Schubert, J. K. Kim, E. F. Schubert, M. Chen, S. Y. Lin, W. Liu, and J. A. Smart, Nat. Photon. 1, 176 (2007).
  4. S. Y. Huang, L. Kavan, I. Exnar, and M. Gratzel, J. Electrochem. Soc. 142, L142 (1995). https://doi.org/10.1149/1.2048726
  5. H. Tang, K. Prasad, R. Sanjines, and F. Levy, Sens. Actuators, B 26, 71 (1995). https://doi.org/10.1016/0925-4005(94)01559-Z
  6. V. Zwilling, M. Aucouturier, and E. Darque-Ceretti, Electrochim. Acta 45, 921 (1991).
  7. D. Gong, C. A. Grimes, O. K. Varghese, W. Hu, R. S. Singh, Z. Chen, and E. C. Dickey, J. Mater. Res. 16, 3331 (2001). https://doi.org/10.1557/JMR.2001.0457
  8. J. M. Macak, H. Tsuchiya, L. Taveira, S. Aldabergerova, and P. Schmuki, Angew. Chem. Int. Ed. 44, 7463 (2005). https://doi.org/10.1002/anie.200502781
  9. G. K. Mor, O. K. Varghese, M. Paulose, K. Shankar, and C. A. Grimes, Sol. Energ. Mater. Sol. Cell. 90, 2011 (2006). https://doi.org/10.1016/j.solmat.2006.04.007