Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-28T09:51:37.910Z Has data issue: false hasContentIssue false

Barium Strontium Titanate Thin Film Capacitors for Low Inductance Decoupling Applications

Published online by Cambridge University Press:  11 February 2011

J. D. Baniecki
Affiliation:
Fujitsu Laboratories Ltd., 10–1 Morinosato-Wakamiya, Atsugi 243–0197, Japan
T. Shioga
Affiliation:
Fujitsu Laboratories Ltd., 10–1 Morinosato-Wakamiya, Atsugi 243–0197, Japan
K. Kurihara
Affiliation:
Fujitsu Laboratories Ltd., 10–1 Morinosato-Wakamiya, Atsugi 243–0197, Japan
Get access

Abstract

Sputter deposited barium strontium titanate (BST) based thin film capacitors have been developed for use in GHz LSI decoupling applications. The fabricated 1.60×1.85 mm2 BST chip decoupling capacitors with Pt electrodes and 150 μm bump pitch, have a capacitance density of 1.2 μF/cm2, low equivalent series inductance of 15 pH, and a low equivalent series resistance of 0.02 Ω. The impedance of the chip capacitors at 1 GHz is over 1000 times lower than conventional multilayered ceramic capacitors. Fundamental electrical and reliability properties of Pt/BST/Pt thin film capacitor structures were also investigated. Capacitors with 200 nm thick BST thin films deposited at 500 °C by RF magnetron sputtering achieved a C/A of 1.8 μF/cm2, leakage current density < 10-9 A/cm2 at 2 volts, and a breakdown field > 2.5 MV/cm at 20 °C. A fit of the failure data to a Weibull distribution indicated at least two different physical mechanisms causing capacitor failure. The primary failure mechanism for 1.5 volt operation was due to resistance degradation without catastrophic capacitor failure. At higher applied voltages, catastrophic capacitor failure occurred with the breakdown event characterized by a thermal runway process. The physical mechanisms contributing to capacitor failure are interpreted to be due to ionic migration and charge injection, and the contribution of these mechanisms to the degradation process could be partially resolved by bi-polar voltage pulse stressing. The projected mean time to failure for 1.5 volt operation is extrapolated to be in excess of 104 years at 75 °C and 126 years at 125 °C. The results indicate that sputter deposited BST thin film capacitors are promising for future GHz LSI decoupling applications.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1] Chun, S., Swaminathan, M., Smith, L. D., Srinivasan, J., Jin, Z., Iyer, M. K., 50th Electronic Components and Technology Conference, pp.760768, 2000.Google Scholar
[2] Takken, T. and Tuckerman, D., Proc IEEEE Multi-Chip Module Conference, pp.79 – 84, 1993.Google Scholar
[3] Bhattacharya, S., Tummala, R., Journal of Materials Science, Materials in Electronics, 11, 253268 (2000).Google Scholar
[4] Imanaka, Y., Shioga, T., and Baniecki, J.D., Fujistu Sci. Tech. J., 38, 22 (2002)Google Scholar
[5] Fukumaru, F., Nagkari, S., Konushi, S., Nishikawa, H., Kamigaki, K., Nambu, S., Mat. Res. Soc. Symp. Proc. Vol. 541, 573 (1999)Google Scholar
[6] Kotecki, D.E., Baniecki, J.D., Shen, H., Laibowitz, R.B., Saenger, K.L., Lian, J.J., Shaw, T.M., Athavale, S.D., Cabral, C. Jr, Duncombe, P.R., Gutsche, M., Kunkel, G., Park, Y.J., Wang, Y., and Wise, R., IBM J. Res. Develop. 43, 367 (1999)Google Scholar
[7] Baniecki, J.D., Cross, J.S., and Tsukada, M., Appl. Phys. Lett., 81, 3837 (2002)Google Scholar
[8] Hwang, C.S., Lee, B. T., Kang, C. S., Kim, J. W., Lee, K. H., Cho, H. J., Horii, H., Kim, W. D., Lee, S. I., Roh, Y. B., and Lee, M. Y., J. Appl. Phys. 83, 3703 (1998)Google Scholar
[9] Bethe, H.A., MIT Radiat. Lab. Rep., 43 (1942)Google Scholar
[10] Simmons, J.G., Phys. Rev. Lett. 15, 967 (1965)Google Scholar
[11] Zafar, S., Jones, R.E., Jiang, B., White, B., Kaushik, V., and Gillespie, S., Appl. Phys. Lett. 73, 3533 (1998)Google Scholar
[12] Dietz, G.W., Schumacher, M., Waser, R., Streiffer, S.K., Basceri, C., and Kingon, A. I., J. Appl. Phys. 82, 2359 (1997)Google Scholar
[13] Baniecki, J. D., Laibowitz, R. B., Shaw, T. M., Parks, C., Lian, J., Xu, H., Ma, Q. Y., J. Appl. Phys. vol. 89, pp. 28732885, (2001)Google Scholar
[14] Schroeder, H. and Schmitz, S., presented at the Fall MRS meeting, Boston, Ma (2002)Google Scholar
[15] Schultz, W., Z. Physik 138, 598 (1954)Google Scholar
[16] Crowell, C.R. and Sze, S.M., Solid-State Electronics 9, 1035 (1966)Google Scholar
[17] Scott, J.F., Ferroelectric Memories, Springer-Verlag, pp 98104 (2000)Google Scholar
[18] Choi, G.M., Tuller, H.L., and Goldschmidt, D., Phys. Rev. B 34, 6972 (1986)Google Scholar
[19] Sze, S.M., “Physics of Semiconductor Devices”, John Wiley and Sons, 246311 (1981)Google Scholar
[20] Rhoderick, E.H., Metal-semiconductor contacts, Clarendon Press, Oxford, 2546, (1978)Google Scholar
[21] Rideout, V.L., Thin Solid Films, 48, 261 (1978)Google Scholar
[22] Wagner, C., Phys. Z., 32, 641 (1931)Google Scholar
[23] Schottky, W., Phys. Z., 32, 833 (1931)Google Scholar
[24] Rhoderick, E.H., Metal-semiconductor contacts, Clarendon Press, Oxford, 81, (1978)Google Scholar
[25] Gossick, B.R., Solid State Electronics, 6, 445 (1963)Google Scholar
[26] Baniecki, J.D., Shioga, T., Kurihara, K., to be publishedGoogle Scholar
[27] Numata, K., Fukuda, Y., Aoki, K., and Nishimura, A., Jap. J. Appl. Phys., 34, 5425 (1995)Google Scholar
[28] Basceri, C., Wells, M.A., Streiffer, S.K., Kingon, A. I., Bilodeau, S., Carl, R., and van Buskirk, P.C., Summerfelt, S.R., and McIntyre, P., “Resistance Degradation of CVD (Ba,Sr)TiO3 Thin Films for DRAMs and Integrated Decoupling Capacitors”, ISAF Symposium Proceedings, pp 5154, (1996)Google Scholar
[29] Horikawa, T., Kawahara, T., Yamamuka, M. and Ono, K., IEEE International Reliability Physics Symposium Proceedings, 35th annual, pp 8289 (1997)Google Scholar
[30] Zafar, S., Hradsky, B., Gentile, D., Chu, P., Jones, R.E., and Gillespie, S., J. Appl. Phys, 86, 3890 (1999)Google Scholar
[31] Saha, S. and Krupanidhi, S.B., J. Appl. Phys, 87, 3056 (2000)Google Scholar
[32] Scott, J.F., Azuma, M., Paz de Araujo, C.A., McMillan, L.D., Scott, M.C., and Roberts, T., Int. Ferro. Vol 4, 61 (1994)Google Scholar
[33] Noma, A. and Ueda, D., Int. Ferro. Vol. 15, 69 (1997)Google Scholar
[34] Waser, R., J. Am. Ceram. Soc. 74, 1934 (1991)Google Scholar
[35] Harari, E., J. Appl. Phys. 49, 2478 (1978)Google Scholar