Materials Transactions Online

Materials Transactions, Vol.48 No.12 (2007) pp.3197-3200
© 2007 The Japan Institute of Metals

Evaluation of Electric Properties for Niobium Capacitors

Sung Man Jung1, In Sung Bae2, Jae Sik Yoon3, Shoji Goto4 and Byung Il Kim1,3

1Department of Material Science and Metallurgical Engineering, Sunchon National University, Sunchon 540-742, Korea
2Korea Institute of Rare Metals, Sunchon 540-742, Korea
3Korea Basic Science Institute, Sunchon Branch, Sunchon 540-742, Korea
4Department of Materials Science and Engineering, Faculty of Engineering and Resource Science, Akita University, Akita 010-8502, Japan

In order to evaluate the applicability of niobium powder, which was manufactured by the external continuous supply method, as a capacitor, the present study measured capacitor performance evaluation factors such as leakage current, permittivity loss (tanδ), capacitance, impedance, equivalent series resistance, etc.
Capacitance decreased significantly from 156 μF in electrolyte (wet cap) to 130 μF after carbon (C)/silver (Ag) solution coating, and around 105 μF after aging, falling within the capacity tolerance of tantalum capacitors. If capacitance was converted to CV/g, it was around 81,000 CV/g. Permittivity loss (tanδ) decreased significantly from 12.9% after C/Ag coating to 7.7% after aging, satisfying the general standard level of 10% or less. Leakage current was 2.41 μA after C/Ag coating and 2.93 μA after aging, both less than the standard level of 6.3 μA. As a whole, the niobium capacitor showed somewhat more unstable characteristics than commercial tantalum capacitors but can be considered applicable as a substitute for tantalum capacitors in the future.

(Received 2007/7/23; Accepted 2007/10/17; Published 2007/11/7)

Keywords: niobium powder, external continuous supply method, capacitance, leakage current, permittivity loss, impedance, equivalent series resistance

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REFERENCES

  1. G. Gauje and R. Brunetaud: Rev. Phys. Appl. 5 (1970) 513.
  2. F. J. Cadieu and N. Chencinski: Inst. Phys. Conf. Ser. 39 (1978) 642.
  3. J. E. Kunzler et al.: Phys. Rev. Lett. 6 (1961) 89.
  4. K. Mendelssohn and J. L. Olsen: Proc. Phys. Soc. 63 (1950) 2.
  5. M. Bidault and J. Dosdat: Rev. Phys. Appl. 5 (1970) 505.
  6. J. S. Yoon, H. H. Park, I. S. Bae, S. Goto and B. I. Kim: J. Japan Inst. Met. 68 (2004) 247.
  7. S. C. Jain, D. K. Bose and C. K. Gupta: Trans. Indian Inst. Met. 24 (1971) 1.
  8. K. Wayne, H. Waban and J. P. Matin: U. S. Pat. 2,927,855. Mar. 8 (1960).
  9. F. C. Aris and T. J. Lewis: J. Phys. 6 (1973) 1067.
  10. M. W. Jones and D. M. Hughes: J. Phys. 7 (1974) 112.
  11. G. P. Klein: J. Electrochem. Soc. 113 (1966) 348.
  12. V. Trifonova and A. Girginow: J. Electroanal. Chem. 107 (1980) 105.

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