Ferroelectric thin film characterization using superconducting microstrip resonators

Author

Galt, D. ; Price, J.C. ; Beall, J.A. ; Harvey, T.E.

Author_Institution

Dept. of Phys., Colorado Univ., Boulder, CO, USA

Volume

5

Issue

2

fYear

1995

fDate

6/1/1995 12:00:00 AM

Firstpage

2575

Lastpage

2578

Abstract

We describe a novel technique for characterizing the dielectric response of ferroelectric thin films at microwave frequencies. The method involves a microstrip resonator which incorporates a ferroelectric capacitor at its center. To demonstrate this method rye have fabricated a superconducting microstrip resonator from a laser-ablated YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) film on a LaAlO/sub 3/ (LAO) substrate with a SrTiO/sub 3/ (STO) capacitor at its center. We report the observed dielectric behavior of the STO laser ablated film as a function of bias at liquid He and N/sub 2/ temperatures and at high and low frequencies. It is observed that the electrically tunable dielectric constant of the STO film is roughly independent of frequency up to 20 GHz (especially at high bias). The loss tangent of the STO/LAO capacitor decreases with increasing bias and is apparently independent of frequency between 6 and 20 GHz.<>

Keywords

barium compounds; dielectric loss measurement; ferroelectric capacitors; ferroelectric materials; ferroelectric thin films; high-temperature superconductors; microstrip resonators; microwave measurement; permittivity measurement; strontium compounds; superconducting microwave devices; superconducting resonators; yttrium compounds; 6 to 20 GHz; HTS microwave components; YBa/sub 2/Cu/sub 3/O/sub 7/-SrTiO/sub 3/-LaAlO/sub 3/; dielectric response; electrically tunable dielectric constant; ferroelectric thin film; laser ablation; loss tangent; microwave frequencies; superconducting microstrip resonators; thin film characterization; Capacitors; Dielectric substrates; Dielectric thin films; Ferroelectric materials; Masers; Microstrip resonators; Microwave frequencies; Superconducting microwave devices; Superconducting thin films; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.403116

Filename

403116