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Characteristics of TiO2 and Ag/TiO2 optical thin film by Co-sputtering method

동시 스퍼터링법에 이용하여 제작한 TiO2와 Ag/TiO2 광학 박막의 특성

  • Published : 2005.02.01

Abstract

Ag-doped $TiO_2$ thin films were prepared by RF magnetron co-sputtering method, and their physical and chemical properties were examined as a function of calcination temperature. XRD results showed that the crystallite size of Ag-doped films was smaller than that of the $TiO_2$ thin films. SEM results showed that the particle size of $Ag/TiO_2$ film was smaller and more uniform than pure $TiO_2$ film. The films had high transparency in the visible range. The films calcined at $600^{\circ}C$ were the anatase phase, and the films calcined at $900^{\circ}C$ were a mixture of anatase and rutile phases. The absorption edge of films calcined at $900^{\circ}C$ was red-shifted. This is due to the augmented absorption resulting from the phase transformation from anatase to rutile phase. And the transmittance of films decreased by the light scattering and absorption in the films. Photocatalytic activity of $Ag/TiO_2$ thin films was higher than that of the pure $TiO_2$ thin films.

고주파 마그네트론 동시 스퍼터링법을 이용하여 $TiO_2$ 박막에 Ag를 도핑한 $Ag/TiO_2$ 박막을 제작하고, 열처리 온도에 따른 박막의 물리적, 화학적 특성을 조사하였다. XRD 측정 결과로부터 금속을 도핑한 박막이 순수 $TiO_2$ 박막보다 결정크기가 더 작은 것을 확인하였으며, SEM 측정 결과로부터 $Ag/TiO_2$ 박막은 순수 $TiO_2$ 박막보다 골자의 크기가 작고 균일하다는 것을 알 수 있었다. 제작된 박막은 가시광선 영역에서 높은 투과율을 나타내었다. $600^{\circ}C$에서 열처리한 박막은 아나타제 결정상이 나타났으며, $900^{\circ}C$에서 열처리한 박막은 아나타제와 루타일상이 혼합되어 나타났다 특히, $900^{\circ}C$에서 열처리한 경우 아나타제에서 루타일로의 상전이에 따른 밴드갭 에너지의 변화에 의해 박막의 흡수단이 장파장 영역으로 이동하였다. 또한 박막 내의 흡수와 산란효과에 의해 투과율이 감소하였다. $Ag/TiO_2$ 박막의 광활성은 순수 $TiO_2$ 박막보다 우수함을 알 수 있었다.

Keywords

References

  1. L. Miao, P. Jin, K. Kaneko, A. Terai, N. Nabatova-Gabain and S. Tanemura, 'Preparation and characterization of polycrystalline anatase and rutile $TiO_2$ thin films by rf magnetron sputtering,' Appl. Surf. Sci., vol 212-213, pp. 255-263, 2003 https://doi.org/10.1016/S0169-4332(03)00106-5
  2. S. K. Zheng, T. M. Wang, G. Xiang and C. Wang, 'Photocatalytic activity of nanostructured $TiO_2$ thin films prepared by de magnetron sputtering method,' Vacuum, vol. 62, pp. 361-366, 2001 https://doi.org/10.1016/S0042-207X(01)00353-0
  3. H. Kostlin, G. Frank, G. Hebbinghaus, H. Auding and K. Denissen, 'Optical filters on linear halogen-lamps prepared by dip-coatering,' J. Non-Cryst. Solids, vol. 218, pp. 347-353, 1997 https://doi.org/10.1016/S0022-3093(97)00169-5
  4. Y. Yan, S. R. Chaudhuri and A. Sarkar, 'Synthesis, characterizations, and optical properties of stacked porous thin films derived from sol-gel process,' J. Am. Ceram. Soc., vol. 79, pp. 1061-1065, 1996 https://doi.org/10.1111/j.1151-2916.1996.tb08548.x
  5. H. Tang, K. Prasad, R. Sanjines and F. Levy, '$TiO_2$ anatase thin films as gas sensors,' Sens. Actuators B, vol. 26-27, pp. 71-75, 1995 https://doi.org/10.1016/0925-4005(94)01559-Z
  6. J. Zhai, T. Yang, L. Zhang and X. Yao, 'The optical wave-guiding properties of $TiO_2-SiO_2$ composite films prepared by the sol-gel process,' Ceram. International, vol. 25, pp. 667-670, 1999 https://doi.org/10.1016/S0272-8842(98)00081-9
  7. J. C. Yu, J. Yu and T. Zhao, 'Enhanced photocatalytic activity of mesoporous and ordinary $TiO_2$ thin films by sulfuric acid treatment,' Appl. Catal. B, vol. 36, pp. 31-43, 2002 https://doi.org/10.1016/S0926-3373(01)00277-6
  8. J. Yu, X. Zhao and Q. Zhao, 'Photocatalytic activity of nanometer $TiO_2$ thin films prepared by the sol-gel method,' Mater. Chem. Phys., vol. 69, pp. 25-29, 2001 https://doi.org/10.1016/S0254-0584(00)00291-1
  9. H. Bach and D. Krause, Thin Films on Glass,(Springer-Verlag, Berlin, Germany, 1997), Chapter 4
  10. F. Lapostolle, A. Billard and J. von Stebut, 'Structure/mechanical properties relationship of titanium-oxygen coating reactively sputter-deposited,' Surf. Coat. Technol., vol. 135, pp. 1-7, 2000 https://doi.org/10.1016/S0257-8972(00)00721-0
  11. A. R. Bally, E. N. Korbeinikova, P. E. Schmid, F. Levy and F. Bussy, 'Structural and electrical properties of Fe-doped $TiO_2$ thin films,' J. Phys. D: Appl. Phys., vol. 31, pp. 1149-1154, 1998 https://doi.org/10.1088/0022-3727/31/10/004
  12. G. Zhao, H. Kozuka and T. Yoko, 'Sol-gel preparation and photoelectrochemical properties of $TiO_2$ films containing Au and Ag metal particles,' Thin Solid Films, vol. 277, pp. 147-154, 1996 https://doi.org/10.1016/0040-6090(95)08006-6
  13. A. Aidla, T. Uustare, A. A. Kiisler, J. Aarik and V. Sammelselg, 'Effect of crystal structure on optical properties of $TiO_2$ films grown by atomic layer deposition,' Thin Solid Films, vol. 305, pp. 270-273, 1997 https://doi.org/10.1016/S0040-6090(97)00135-1
  14. H. Ohsaki, T. Tachibana, A. Hayashi, A. Mitsui and Y. Hayashi, 'High rate sputter deposition of $TiO_2$ from $TiO_{2-x}$ target,' Thin Solid Films, vol. 351, pp. 57-60, 1999 https://doi.org/10.1016/S0040-6090(99)00207-2
  15. D. Bhattacharyya, N. K. Sahoo, S. Thakur and N. C. Das, 'Spectroscopic ellipsometry of $TiO_2$ layers prepared by ion-assisted electron-beam evaporation,' Thin Solid Films, vol. 360, pp. 96-102, 2000 https://doi.org/10.1016/S0040-6090(99)00966-9
  16. B. D. Cullity, Elements of X-Ray Diffraction (Addison-wesley, Notre Dam, USA, 1978), Chapter 9
  17. D. Mardare and G. I. Rusu, 'Structural and electrical properties of $TiO_2$ RF sputtered thin films,' Mat. Sci. Eng., vol. B75, pp. 68-71, 2000 https://doi.org/10.1016/S0921-5107(00)00387-1
  18. D. Mardare, M. Tasca, M. Delibas and G. I. Rusu, 'On the structural properties and optical transmittance of $TiO_2$ r.f. sputtered thin films,' Appl. Surf. Sci., vol. 156, pp. 200-206, 2000 https://doi.org/10.1016/S0169-4332(99)00508-5
  19. F. H. Lu, F. X. Fang and Y. S. Chen, 'Eutectic reaction between copper oxide and titanium dioxide,' J. European Ceram. Soc., vol 21, pp. 1093-1099, 2001 https://doi.org/10.1016/S0955-2219(00)00298-3
  20. A. Hilmi, John H. T. Luong and An-Lac Nguyen, 'Utilization of $TiO_2$ deposited on glass plates for removal of metals from aqueous wastes,' Chemosphere, vol. 38, pp. 865-874, 1999 https://doi.org/10.1016/S0045-6535(98)00225-2
  21. R. Laird, and A. Belkind, 'Cosputtered films of mixed $TiO_2/SiO_2$,' J. Vac. Sci. Technol., vol A10, pp. 1908-1912, 1992
  22. J. W. Yoon, T. Sasaki and N. Koshizaki, E. Traversa, 'Preparation and characterization of $M/TiO_2$ (M=Ag, Au, Pt) nanocomposite thin films,' Scripta Materialia, vol. 44, pp. 1865-1868, 2001 https://doi.org/10.1016/S1359-6462(01)00732-1
  23. H. Poelman, D. Poelman, D. Depla, H. Tomaszewski, L. Fiermans and R. D. Gryse, 'Electronic and optical characterisation of $TiO_2$ films deposited from ceramic targets,' Surf. Sci., vol. 482-485, pp. 940-945, 2001 https://doi.org/10.1016/S0039-6028(01)00931-1
  24. M. Anpo, T. Shima, S. Kodama and Y. Kubokawa, 'Photocatalytic hydrogenation of CH3CCH with $H_2O$ on small-particle $TiO_2$: size quantization effects and reaction Intermediates,' J. Phys. Chem., vol. 91, pp. 4305-4310, 1987 https://doi.org/10.1021/j100300a021
  25. T. M. Wang, S. K. Zheng, W. C. Hao and C. Wang, 'Studies on photocatalytic activity and transmittance spectra of $TiO_2$ thin films prepared by r.f magnetron sputtering method,' Surf. Coat. Tech., vol. 155, pp. 141-145, 2002 https://doi.org/10.1016/S0257-8972(02)00004-X
  26. S. Sakthivel, M. V. Shankar, M. Palanichamy, B. Arabindoo, D. W. Bahnemann and V. Murugesan, 'Enhancement of photocatalytic activity by metal deposition: characterisation and photonic efficiency of Pt, Au and Pd deposited on $TiO_2$ catalyst,' Water Res., vol. 38, pp. 3001-3008, 2004 https://doi.org/10.1016/j.watres.2004.04.046
  27. W. C. Hao, S. K. Zheng, C. Wang and T. M. Wang, 'Comparison of the photocatalytic activity of $TiO_2$ powder with different particle size,' J. Mat. Sci. Lett., vol. 21, pp. 1627-1629, 2002 https://doi.org/10.1023/A:1020386019893