Impedance fluctuations in epitaxial PZT films
2001 (English)In: Integrated Ferroelectrics, ISSN 1058-4587, Vol. 38, no 04-jan, 647-656 p.Article in journal (Refereed) Published
We report on measurements of impedance of Au/PZT/La0.67Sr0.33MnO3/Pt80Ir20 thin film capacitors performed in the time domain. Ferroelectric PZT films pulsed laser deposited on bulk polycrystalline Pt80Ir20 substrates demonstrate good ferroelectric properties: dielectric permittivity epsilon' = 880 and loss tandelta = 0.039 at 1 kHz, remnant polarization as high as 20 muC/cm(2), induced polarization of 40 muC/cm(3) at 380 kV/cm, and coercive field of 52.5 kV/cm. Resistivity of PZT film at coercive field was found to be 3.10(12) Omega.cm. Instantaneous C-V and I-V characteristics have been recorded to study the relaxation of polarization. Transient current exhibits non-Debye type relaxation, which has been nicely fitted to Curie-von Schweindler law j = j(leak) + j(o) (t/1sec)(-n) with an exponent nsimilar to0.8 while the power law C proportional to f(-0.1) has been found in frequency dispersion of the capacitance. Impedance fluctuation spectrum in the true leakage and resistance degradation regimes was found to follow 1/f(1.5) dependence. Close to breakdown field voltage fluctuations in ferroelectric capacitor increase, become non-steady randomly spike-shaped.
Place, publisher, year, edition, pages
2001. Vol. 38, no 04-jan, 647-656 p.
pulsed laser deposition, thin ferroelectric PZT films, relaxation of polarization, impedance fluctuations, noise
IdentifiersURN: urn:nbn:se:kth:diva-21224ISI: 000173066600002OAI: oai:DiVA.org:kth-21224DiVA: diva2:339922
QC 201005252010-08-102010-08-10Bibliographically approved