Berlin 2008 – wissenschaftliches Programm

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DF: Fachverband Dielektrische Festkörper

DF 11: Dielectric and ferroelectric thin films and nanostructures I

DF 11.4: Vortrag

Mittwoch, 27. Februar 2008, 15:00–15:20, EB 107

Ferroelectric lithography on doped LiNbO₃ single crystals — •Alexander Haußmann and Lukas M. Eng — Institut für Angewandte Photophysik, Technische Universität Dresden, D-01062 Dresden

The presence of different surface charges and thus different surface reactivities offers the possibility of exploiting domain-structured ferroelectrics as templates for nanostructure assembling. Recent work has reported on the photochemical adsorption of noble-metal nanoparticles to such surfaces serving as pin-points for attaching desired organic molecules [1].

Here, we report on the formation of domain structures of µm-sizes in 5 mol% Mg-doped congruent LiNbO₃ single crystals by (a) UV-induced poling using a HeCd laser beam (λ = 325 nm) focused through liquid electrodes, as well as (b) the application of high voltage between a contact mode AFM tip and a back electrode. Subsequently, the deposition of wire-like metal structures at the domain wall positions was stimulated by illuminating the sample dipped into aqueous solutions of AgNO₃ or Pt(NO₃)₂ by super bad-gap illumination (λ < 310 nm) using a Hg spectral lamp. Structural properties of the resulting nano- and mesowires were examined using non-contact AFM and Kelvin probe force microscopy [2]. Electrical conductivity of 300 µm long Pt wires between macroscopic electrodes could be demonstrated by performing I-V-scans.

[1] S.V. Kalinin, D.A. Bonnell et al., Nano Letters 2, 589 (2002)

[2] U. Zerweck, Ch. Loppacher et al., Phys. Rev. B 71, 125424 (2005)