Abstract
We describe materials deposition and characterization for a broad class of tunable microwave devices using high-temperature oxide superconductor and voltage-tunable oxide ferroelectric thin-film multilayer structures. Tl-Ba-Ca-Cu-O thin films deposited by sputtering ore-beam evaporation were patterned into microwave resonators, each consisting of two colinear microstrip line sections separated by a 5–20μm gap. A Ba0.1Sr0.9TiO3 (BST) layer was then over-coated to fill the gap. The relative dielectric constant of the BST films deposited by physical vapor or chemical techniques was measured at 77 K in the 1–10 MHz range and found to vary by up to a factor of 2 or more with voltage bias in test capacitor structures using Pt electrodes. In the BST (variable capacitor)-HTSC microwave resonator structures, the change of the relative dielectric constant of the BST under voltage bias has allowed variation of the fundamental frequency of up to 80 MHz in the 5–10 GHz range at 4 K. Film deposition by various techniques and associated structural, morphological, and electronic properties, as well as materials compatibility issues, are discussed.
Similar content being viewed by others
References
A. M. Hermann, J. C. Price, J. F. Scott, R. M. Yandrofski, A. Naziripour, D. Galt, H. M. Duan, M. Paranthaman, R. Tello, J. Cuchiaro, and R. K. Ahrenkiel,Bull. Am. Phys. Soc. 38, 689 (1993).
D. Galt, J. C. Price, J. A. Beall, and R. Ono,Bull. Am. Phys. Soc. 38, 840 (1993).
J. A. Beall, R. H. Ono, D. Galt, and J. C. Price,IEEE MTTS Digest, 1421 (1993).
D. Galt, J. C. Price, J. A. Beall. and R. H. Ono,Appl. Phys. Lett. 63, 3078 (1993).
F. Barnes, private communication
D. S. Ginley, C. I. H. Ashby, T. A. Plot, D. Urea, M. P. Siegal, and J. S. Martens,Appl. Phys. Lett. 63, 2429 (1993).
A. Naziripour, H. M. Duan, R. Tello, D. S. Ginley, R. Bhattacharya, R. Blaugher, and A. M. Hermann,Physica C 200, 334 (1992).
A. Naziripour, A. M. Hermann, A. B. Swartzlander, A. J. Nelson, and C. Dong,Proc. of the Beijing International Conf. on High-T c Superconductivity, 1992 in press.
R. C. Taber,Rev. Sci. Instrum. 61, 2200 (1990).
C. M. Jackson, J. H. Kobayashi, A. Lee, C. Pretiette-Hall, J. F. Burch, and R. Hu,Microwave Opt. Technol. Lett. 5, 722 (1992).
K. C. Gupta, R. Garg, and I. J. Bhal,Microstrip Lines and Slotlines (Artech House, Denhan, Massachusetts, 1979).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hermann, A.M., Yandrofski, R.M., Scott, J.F. et al. Oxide superconductors and ferroelectrics—Materials for a new generation of tunable microwave devices. J Supercond 7, 463–469 (1994). https://doi.org/10.1007/BF00724590
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00724590