Skip to main content

Advertisement

SpringerLink
Log in

Reassessment of degradation mechanisms in anodic tantalum oxide capacitors under high electric fields

  • Original Paper
  • Published:
Journal of Materials Science Aims and scope Submit manuscript

Abstract

High-voltage Ta capacitors have broad applications in various electric systems. Anodically grown, amorphous tantalum oxide (ATO) serves as the dielectric in these capacitors. A detailed understanding of the behavior of ATO exposed to high electric fields is highly desirable and is reflected in a number of prior investigations into this subject. In the conventional view, the electric field promotes the growth of crystalline oxide, which is electrically more conductive and thus leads to the degradation of the dielectric. This interpretation is re-examined using several advanced characterization techniques. The results indicate that oxidation of the ATO and underlying Ta occurs preferentially at specific locations. Subsequent crystallization at these sites was only observed in specimens where this enhanced oxidation led to cracking in the ATO. The results with different Ta materials indicate that these cracks are more prevalent with rougher surfaces. The reported sequence of mechanisms that leads to crystallization provides new insight that can potentially be employed to improve the reliability and stability of Ta capacitors.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others

References

  1. Jackson NF (1973) Field crystallization of anodic films on tantalum. J Appl Electrochem 3(2):91–98. doi:10.1007/bf00613498

    Article  Google Scholar 

  2. Goudswaard B, Driesens FJJ (1976) Failure mechanism of solid tantalum capacitors. Electrocompon Sci Technol 3(3):171–179. doi:10.1155/apec.3.171

    Article  Google Scholar 

  3. Yang L, Viste M, Hossick-Schott J, Sheldon BW (2012) Internal stress evolution during field-induced crystallization of anodic tantalum oxide. Electrochim Acta 81:90–97. doi:10.1016/j.electacta.2012.07.035

    Article  Google Scholar 

  4. Lai BCM, Lee JYM (1999) Leakage current mechanism of metal-Ta2O5-metal capacitors for memory device applications. J Electrochem Soc 146(1):266–269. doi:10.1149/1.1391597

    Article  Google Scholar 

  5. Oehrlein GS, Reisman A (1983) Electrical properties of amorphous tantalum pentoxide thin films on silicon. J Appl Phys 54(11):6502–6508

    Article  Google Scholar 

  6. Wright SW, Judge CP, Lee MJ, Bowers DF, Dunbar M, Wilson CD (2012) Thin film high dielectric constant metal oxides prepared by reactive sputtering. J Vac Sci Technol B 30(6):062202. doi:10.1116/1.4757132

    Article  Google Scholar 

  7. Sethi G, Olszta M, Jing L, Sloppy J, Horn MW, Dickey EC, Lanagan MT (2007) Structure and dielectric properties of amorphous tantalum pentoxide thin film capacitors. In: Annual Report—Conference on Electrical Insulation and Dielectric Phenomena, 2007. CEIDP 2007, 14–17 Oct. 2007, pp. 815–818. doi:10.1109/ceidp.2007.4451491

  8. Draper PHG, Jacobs PWM (1963) Kinetics of the formation of anodic oxide films on tantalum. Trans Faraday Soc 59:2888–2898. doi:10.1039/tf9635902888

    Article  Google Scholar 

  9. Vermilyea DA (1955) The crystallization of anodic tantalum oxide films in the presence of a strong electric field. J Electrochem Soc 102(5):207–214. doi:10.1149/1.2430031

    Article  Google Scholar 

  10. Joshi PC, Cole MW (1999) Influence of postdeposition annealing on the enhanced structural and electrical properties of amorphous and crystalline Ta2O5 thin films for dynamic random access memory applications. J Appl Phys 86(2):871–880. doi:10.1063/1.370817

    Article  Google Scholar 

  11. Virkki J, Seppala T, Frisk L, Heino P (2010) Accelerated testing for failures of tantalum capacitors. Microelectron Reliab 50(2):217–219. doi:10.1016/j.microrel.2009.11.006

    Article  Google Scholar 

  12. Virkki J, Sydanheimo L, Raumonen P (2011) Modifications of the 85/85 test and the temperature cycling test for tantalum capacitors. Solder Surface Mount Technol 23(3):168–176. doi:10.1108/09540911111146926

    Article  Google Scholar 

  13. Sedghi N, Davey W, Mitrovic IZ, Hall S (2011) Reliability studies on Ta(2)O(5) high-kappa dielectric metal-insulator-metal capacitors prepared by wet anodization. J Vac Sci Technol B 29(1):01AB10. doi:10.1116/1.3532823

    Google Scholar 

  14. Matsumoto T, Sugita E (1975) Properties and reliability of tantalum oxide thin-film capacitor. Rev Electr Commun Laboratories 23(3–4):257–270

    Google Scholar 

  15. Su X, Viste M, Hossick-Schott J, Yang L, Sheldon BW (2013) Electrochemically induced stresses in amorphous tantalum oxide films. J Electrochem Soc 160(11):H829–H835. doi:10.1149/2.089311jes

    Article  Google Scholar 

  16. Yang L, Viste M, Hossick-Schott J, Sheldon B (2013) Understanding internal stress evolution mechanisms associated with field crystallization of anodic tantalum oxide. J Electroceram 1–9. doi:10.1007/s10832-013-9859-z

  17. Li Y-M, Young L (2001) Non-thickness-limited growth of anodic oxide films on tantalum. J Electrochem Soc 148(9):B337–B342. doi:10.1149/1.1386387

    Article  Google Scholar 

  18. Ezhilvalavan S, Tseng TY (1998) Conduction mechanisms in amorphous and crystalline Ta2O5 thin films. J Appl Phys 83(9):4797–4801. doi:10.1063/1.367272

    Article  Google Scholar 

  19. Yahalom J, Zahavi J (1970) Electrolytic breakdown crystallization of anodic oxide films on Al, Ta and Ti. Electrochimica Acta 15(9):1429–1435. doi:10.1016/0013-4686(70)80064-0

    Article  Google Scholar 

  20. Leach JSL, Pearson BR (1988) Crystallization in anodic oxide films. Corros Sci 28(1):43–56. doi:10.1016/0010-938X(88)90005-4

    Article  Google Scholar 

  21. Klerer J (1965) Determination of the density and dielectric constant of thin Ta2O5 films. J Electrochem Soc 112(9):896–899. doi:10.1149/1.2423725

    Article  Google Scholar 

  22. Zhang L, Ju H, Liu B, Zhang Y, Jia B (2014) Research on modification of working electrolyte of hybrid tantalum capacitors with additive. Electron Compon Mater 33(4). doi:10.3969/j.issn.1001-2028.2014.04.006

  23. Bubar SF, Vermilyea DA (1966) Deformation of anodic oxide films. J Electrochem Soc 113(9):892–895. doi:10.1149/1.2424149

    Article  Google Scholar 

  24. Wiklund U, Gunnars J, Hogmark S (1999) Influence of residual stresses on fracture and delamination of thin hard coatings. Wear 232(2):262–269. doi:10.1016/s0043-1648(99)00155-6

    Article  Google Scholar 

  25. Vermilyea DA (1957) Nucleation of crystalline Ta2O5 during field crystallization. J Electrochem Soc 104(9):542–546. doi:10.1149/1.2428649

    Article  Google Scholar 

  26. Surganov VF, Mozalev AM, Lastochkina VA (1998) Investigating the composition of periodic nano-size column structures of anodic titanium oxide by the method of IR spectroscopy. J Appl Spectrosc 65(6):891–897. doi:10.1007/bf02675745

    Article  Google Scholar 

  27. Surganov VF, Mozalev AM, Lastochkina VA (2000) IR spectroscopic investigation of nanosize columnar anodic tantalum oxides formed in a sulfuric-acid electrolyte. J Appl Spectrosc 67(3):412–417. doi:10.1007/bf02683852

    Article  Google Scholar 

  28. Kovarskil AP, Novotel’nova AV, Khanin SD, Chernyus NL (1988) Study of electrically stimulated crystal growth in a metal–amorphous–oxide–electrolyte system by means of secondary-ion mass spectrometry. Sov Phys 33(2)

  29. Kofstad P (1962) On The Defect Structure of Ta2O5. J Electrochem Soc 109(9):776–781. doi:10.1149/1.2425554

    Article  Google Scholar 

Download references

Acknowledgements

We gratefully acknowledge support from Medtronic Inc. and NSF (Award DMR-0805172).

Author information

Authors and Affiliations

  1. School of Engineering, Brown University, 182 Hope Street, Providence, RI, 02912, USA

    Xin Su, Lei Yang & Brian W. Sheldon

  2. Medtronic Energy and Components Center, 6800 Shingle Creek Parkway, Brooklyn Center, MN, 55430, USA

    Mark Viste & Joachim Hossick-Schott

  3. Institute of Orthopaedics, The First Affiliated Hospital, Soochow University, Suzhou, 215006, Jiangsu, People’s Republic of China

    Lei Yang

Authors
  1. Xin Su
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Mark Viste
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Joachim Hossick-Schott
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Lei Yang
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Brian W. Sheldon
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Brian W. Sheldon.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Su, X., Viste, M., Hossick-Schott, J. et al. Reassessment of degradation mechanisms in anodic tantalum oxide capacitors under high electric fields. J Mater Sci 50, 960–969 (2015). https://doi.org/10.1007/s10853-014-8656-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10853-014-8656-7

Keywords

Search

Navigation