Dresden 2006 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
DF: Dielektrische Festkörper
DF 2: Dielectric and Ferroelectric Thin Films and Nanostructures I
DF 2.5: Vortrag
Montag, 27. März 2006, 16:10–16:30, M{\"U}L Elch
Nonlinear phenomena in ferroelectric thin films — •Kay Barz1, M. Diestelhorst1, H. Beige1, M. Alexe2, and D. Hesse2 — 1Martin Luther-Universität Halle-Wittenberg, Germany — 2Max Planck Institute of Microstructure Physics, Germany
Ferroelectric thin films have proven to be an interesting subject to investigate into numerous nonlinear effects. Some of these effects are discussed based on experimental data from a Bi4Ti3O12 Metal-Ferroelectric-Semiconductor (MFS) structure. Firstly the high frequency capacitance-voltage characteristic is compared with simple model derived from a conventional MOS (Metal-Oxide-Semiconductor) structure. From this one can conclude to the influence of interface trap density when measuring a MFS at high frequencies. Secondly the MFS structure is used as capacitor in a LCR resonance circuit. Increasing the driving voltage of the circuit shifts the resonance frequency according to the nonlinearity of the MFS. Finally the investigated specimen shows a torus doubling bifurcation. This nonlinear phenomenon is seldom observable in experiments. A comparison with the behaviour of Metal-Ferroelectric-Metal structures may clarify which of these effects originate from the ferroelectric layer or MOS-typical behavior, respectively.