2000 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.

IEEE Transactions on Microwave Theory and Techniques
Volume 48 Number 4, April 2000

Table of Contents for this issue

Complete paper in PDF format

A K -Band-Frequency Agile Microstrip Bandpass Filter Using a Thin-Film HTS/Ferroelectric/Dielectric Multilayer Configuration

Guru Subramanyam, Senior Member, IEEE Frederick W. Van Keuls, Member, IEEE and Félix A. Miranda Senior Member, IEEE

Page 525.

Abstract:

In this paper, we report on YBa2Cu3O7- (YBCO) thin-film/SrTiO3 (STO) thin-film K-band tunable bandpass filters on LaAlO3 (LAO) dielectric substrates. The two-pole filter has a center frequency of 19 GHz and a 4% bandwidth. Tunability is achieved through the nonlinear dc electric-field dependence of the relative dielectric constant of STO (r, STO). A large tunability (f/fo=(fV,max - fo)/fo,where fo is the center frequency of the filter at no bias and fV,max is the center frequency of the filter at the maximum applied bias) of greater than 10% was obtained in YBCO/STO/LAO microstrip bandpass filters operating below 77 K. A center frequency shift of 2.3 GHz (i.e., a tunability factor of approximately 15%) was obtained at a 400-V bipolar dc bias, and 30 K, with minimal degradation in the insertion loss of the filter. This paper addresses design, fabrication, and testing of tunable filters based on STO ferroelectric thin films. The performance of the YBCO/STO/LAO filters is compared to that of gold/STO/LAO counterparts.

References

  1. R. Keenan, "Superconductors improve base-station sensitivity,"in Wireless Syst. Design, July 1997, p.  32. 
  2. H. Moritz, "Filter brings coverage without interference", Wireless Business Technol., vol. 4, pp.  82-83, 1998.
  3. R. S. Kwok, S. J. Fiedziuszko, F. A. Miranda, G. V. León, M. S. Demo and D. Y. Bohman, "Miniaturized HTS/dielectric multilayer filters for satellite communications", IEEE Trans. Appl. Superconduct., vol. 7, pp.  3706-3709, June  1997.
  4. H. H. S. Javadi, J. G. Bowen, D. L. Rascoe, R. R. Romanofsky, C. M. Chorey and K. B. Bhasin, "Jet Propulsion Laboratory/NASA Lewis Research Center space qualified hybrid high temperature superconducting/semiconducting 7.4 GHz low noise downconverter for NRL HTSSE-II Program", IEEE Trans. Microwave Theory Tech., vol. 44, pp.  1279-1288, July  1996 .
  5. O. G. Vendik, L. T. Ter-Martirosyan, A. I. Dedyk, S. F. Karmanenko and R. A. Chakalov, "High Tc superconductivity: New applications of ferroelectrics at microwave frequencies", Ferroelect., vol. 144, pp.  33-43, 1993.
  6. D. E. Oates, A. Piqué, K. S. Harshavardhan, J. Moses, F. Yang, and G. F. Dionne, "Tunable YBCO resonators on YIG substrates", IEEE Trans. Appl. Superconduct., vol. 7, pp.  2338-2342, June  1997.
  7. A. M. Hermann, R. M. Yandrofski, J. F. Scott, A. Naziripour, D. Galt, J. C. Price, J. Cuchario and R. K. Ahrenkiel, "Oxide superconductors and ferroelectrics-materials for a new generation of tunable microwave devices", J. Superconduct., vol. 7, no. 2, pp.  463-469, 1994.
  8. S. S. Gevorgian, D. I. Kaparkov and O. G. Vendik, "Electrically controlled HTSC/ferroelectric coplanar waveguide", Proc. Inst. Elect. Eng., vol. 141, pp.  501-503, 1994.
  9. F. A. Miranda, R. R. Romanofsky, F. W. Van Keuls, C. H. Mueller, R. E. Treece and T. V. Rivkin, "Thin film multi-layer conductor/ferroelectric tunable microwave components for communication applications", Integrated Ferroelect., vol. 17, pp.  231-246, 1997.
  10. A. T. Findikoglu, Q. X. Jia, X. D. Wu, G. J. Chen, T. Venkatesan and D. W. Reagor, "Tunable and adaptive bandpass filter using a nonlinear dielectric thin film of STO", Appl. Phys. Lett., vol. 68, no.  12, pp.  1651-1653, 1996.
  11. G. Subramanyam, F. W. Van Keuls and F. A. Miranda, "A novel K -band tunable microstrip bandpass filter using a HTS/ferroelectric/dielectric multilayer configuration", IEEE MTT-S Int. Microwave Symp. Dig., vol. 2, pp.  1011-1014, 1998.
  12. G. Subramanyam, F. W. Van Keuls and F. A. Miranda, "A K -band tunable microstrip bandpass filter using a thin film conductor/ferroelectric/dielectric multilayer configuration", IEEE Microwave Guided Wave Lett., vol. 8, pp.  78-80, Feb.  1998.
  13. M. J. Dalberth, R. E. Stauber, J. C. Price, C. T. Rogers and D. Galt, "Improved low frequency and microwave dielectric response in strontium titanate thin films grown by pulsed laser ablation", Appl. Phys. Lett., vol. 72, pp.  507-509, 1998.
  14. G. Matthaei, L. Young and E. M. T. Jones, Microwave Filters, Impedance-Matching Networks, and Coupling Structures , Norwood, MA: Artech House, 1980.
  15. T. Edwards, Foundations of Microstrip Circuit Design, New York: Wiley, 1992.
  16. V. Sadhir and I. Bahl, "Radial line structures for broadband microwave circuit applications", Microwave J., pp.  102 -123, 1991.
  17. "Sonnet em User's Manuals", Sonnet Software, Liverpool, NY, 1997.
  18. R. C. Neville, B. Hoeneisen and C. A. Mead, "Permittivity of strontium titanate", J. Appl. Phys., vol. 43, pp.  2124-2131, 1972.
  19. A. B. Kozyrev, O. I. Soldatenkov, T. B. Samoilova, A. V. Ivanov, C. H. Mueller, T. V. Rivkin and G. A. Koepf, "Response time and power handling capability of tunable microwave devices using ferroelectric thin-films", Integrated Ferroelect., vol. 22, pp.  329-340, 1998.