Korean Journal of Materials Research (한국재료학회지)

Materials Research Society of Korea (한국재료학회)
권호 표지
DOI QR코드

DOI QR Code

Optical Emission Spectroscopy with Parameters During R.F. Discharge of BaTiO3 Target

BaTiO3 타겟의 R.F. 방전 중 변수에 따른 광반사분광 특성

  • Park, Sang-Shik (School of Nano & Materials Engineering, Kyungpook National University)
  • 박상식 (경북대학교 나노소재공학부)
  • Received : 2011.08.16
  • Accepted : 2011.08.31
  • Published : 2011.09.27
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, optical emission spectroscopy was used to monitor the plasma produced during the RF magnetron sputtering of a $BaTiO_3$ target. The intensities of chemical species were measured by real time monitoring with various discharge parameters such as RF power, pressure, and discharge gas. The emission lines of elemental and ionized species from $BaTiO_3$ and Ti targets were analyzed to evaluate the film composition and the optimized growth conditions for $BaTiO_3$ films. The emissions from Ar(I, II), Ba(I, II) and Ti(I) were found during sputtering of the $BaTiO_3$ target in Ar atmosphere. With increasing RF power, all the line intensities increased because the electron density increased with increasing RF power. When the Ar pressure increased, the Ba(II) and Ti(I) line intensity increased, but the $Ar^+$ line intensity decreased with increasing pressure. This result shows that high pressure is of greater benefit for the ionization of Ba than for that of Ar. Oxygen depressed the intensity of the plasma more than Ar did. When the Ar/$O_2$ ratio decreased, the intensity of Ba decreased more sharply than that of Ti. This result indicates that the plasma composition strongly depends on the discharge gas atmosphere. When the oxygen increased, the Ba/Ti ratio and the thickness of the films decreased. The emission spectra showed consistent variation with applied power to the Ti target during co-sputtering of the $BaTiO_3$ and Ti targets. The co-sputtered films showed a Ba/Ti ratio of 1.05 to 0.73 with applied power to the Ti target. The films with different Ba/Ti ratios showed changes in grain size. Ti excess films annealed at $600^{\circ}C$ did not show the second phase such as $BaTi_2O_5$ and $TiO_2$.

Keywords

References

  1. S. Park, Ferroelectrics, 406, 75 (2010). https://doi.org/10.1080/00150193.2010.484344
  2. S. Park, J. Ha and H. N. Wadley, Integrated Ferroelectrics Int. J., 99, 105 (2008). https://doi.org/10.1080/10584580802107809
  3. S. Park, Kor. J. Mater. Res., 20, 374 (2010). https://doi.org/10.3740/MRSK.2010.20.7.374
  4. I. Nakatsugawa, K. Araki, H. Takayasu, K. Saito, K. Matsusaka, T. Endou and A. Shida, Surf. Coating. Tech., 169-170, 307 (2003). https://doi.org/10.1016/S0257-8972(03)00119-1
  5. D. Klemm, V. Hoffmann and C. Edelmann, Vacuum, 84, 299 (2009). https://doi.org/10.1016/j.vacuum.2009.06.058
  6. J. Romero and A. Lousa, Vacuum, 81, 1421 (2007). https://doi.org/10.1016/j.vacuum.2007.04.032
  7. D. R. Lide and H. P. R. Frederikse, Handbook of Chemistry and Physics, 74th ed., p. 10-1, CRC press, London, England (1993).
  8. National Institute of Standards and Technology (NIST), NIST Atomic Spectra Database, Retrieved July 4, 2011 from http://www.nist.gov/pml/data/asd.cfm.
  9. F. Liu, C. S. Ren, Y. N. Wang, X. L. Qi and T. C. Ma, Vacuum, 81, 221 (2006). https://doi.org/10.1016/j.vacuum.2006.03.006
  10. T. Nakano, N. Ohnuki and S. Baba, Vacuum, 59, 581 (2000). https://doi.org/10.1016/S0042-207X(00)00319-5
  11. G. M. Turner, I. S. Falconer, B. W. James and D. R. McKenzie, J. Appl. Phys., 65, 3671 (1989). https://doi.org/10.1063/1.342593
  12. R. F. Bunshah, Handbook of Deposition Technologies for Film and Coatings, 2nd ed., p. 263, Noyes Pub., New Jersey, U.S.A. (1994).
  13. W. Zhu, D. Peng, J. Cheng and Z. Meng, Trans. Nonferrous Met. Soc. China, 16, S261 (2006). https://doi.org/10.1016/S1003-6326(06)60187-8
  14. Y. K. Cho, S. L. Kang and D. Y. Yoon, J. Am. Ceram. Soc., 87, 119 (2004). https://doi.org/10.1111/j.1551-2916.2004.00119.x
  15. J. J. Ritter, R. S. Roth and J. E. Blendell, J. Am. Ceram. Soc., 69, 155 (1986). https://doi.org/10.1111/j.1151-2916.1986.tb04721.x