Dresden 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
DF: Dielektrische Festkörper
DF 7: Poster
DF 7.13: Poster
Mittwoch, 26. März 2003, 14:30–18:00, P2a
Heteroepitaxial growth of barium titanate (BTO) thin films on pretextured electrodes — •Sebastian Dreyer1, Karola Thiele1, Carsten Herweg1, Sibylle Sievers1, Jörg Hoffmann2, and Herbert C. Freyhardt1,2 — 1Institut f. Materialphysik, Universität Göttingen, 37073 Göttingen — 2Zentrum f. Funktionswerkstoffe gem. GmbH ZFW, 37073 Göttingen
In the last years, ferroelectric thin films with high permittivity have obtained an increasing attention, especially for the use in dynamic random access memories (DRAM). The dielectric properties of thin films are strongly dependent on the microstructure. The preferred orientation and the degree of texture of a dielectric film can be changed by a heteroepitaxial growth on a pretextured electrode serving as a template.
Therefore, barium titanate (BTO) thin films were deposited onto biaxially textured conductive indium tin oxide (ITO) films, prepared by ion-beam-assisted deposition (IBAD). The ITO-films show (001)-oriented growth with a distinctive in-plane texture, which is improved with increasing film thickness. Atomic force microscopy (AFM) measurements exhibit flat surfaces with an rms-roughness of 1 nm to 5 nm, depending on the film thickness.
The BTO-films were deposited at T = 600 ∘C onto the ITO-films. X-ray diffraction measurements reveal epitaxial growth in (001)-orientation with an in-plane texture similar to the surface texture of the ITO-films. Beside atomic force microscopy and standard x-ray diffraction, the single- and double-layers are also characterized by small-angle x-ray spectrometry. First dielectric measurements are presented.