Regensburg 2010 – wissenschaftliches Programm

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KR: Fachverband Kristallographie

KR 3: Poster: Crystallography in Nanoscience

KR 3.2: Poster

Mittwoch, 24. März 2010, 15:00–17:30, Poster A

Structure of W-C-nanodots prepared by focused electron beam induced deposition as determined by electron diffraction — •Iryna Andrusenko¹, Tatiana Gorelik¹, Andrew Stewart¹, Ute Kolb¹, Mike Strauss², Roland Sachser³, Fabrizio Porrati³, and Michael Huth³ — ¹Institute of Physical Chemistry, University Mainz, Mainz, Germany — ²Department of Structural Biology, MPI of Biophysics, Frankfurt/Main, Germany — ³Physikalisches Institut, Goethe University, Frankfurt/Main, Germany

Ordered two-dimensional nanodot lattices of various lattice pitches were fabricated from W(CO)₆ precursor by focused electron-beam-induced deposition (FEBID) on amorphous carbon or silicon templates. Electron transmission microscopy images and diffraction patterns were collected at 300 kV with a FEG-TEM. Tomographic reconstructions from images taken at liquid nitrogen temperature were generated by weighted back-projection from 85 zero-loss filtered images taken over a tilt range of ±63 degrees at a nominal defocus of -1 µm and a magnification of 48000. Electron diffraction patterns, providing resolution superior to imaging techniques, were performed using selected area electron diffraction as well as a semi-parallel beam of 50 nm diameter. Diffraction patterns of the full 1x1 µm dot lattice area delivered a mean distance of about 2.3 Å indicating a W-C bond length. Diffraction patterns of single particles have been collected in order to reconstruct high resolution images. The structural features of FEBID grown W-C-nanodots investigated by electron diffraction were subsequently correlated with Raman spectroscopy results.