AbstractsPhysics

Development and Implementation of a Nanotomography Setup at the PETRA III Beamline P05

by Malte Ogurreck




Institution: Christian-Albrechts-Universität zu Kiel
Department: Mathematisch-Naturwissenschaftliche Fakult├Ąt
Degree: PhD
Year: 2014
Record ID: 1099634
Full text PDF: http://macau.uni-kiel.de/receive/dissertation_diss_00016132


Abstract

X-ray nanotomography is used to analyze materials on the sub-micrometer scale. Many soft biological materials, i.e. most organic tissues, can be imaged with soft X-rays. For materials with a higher electron density, such as bone or teeth, metals, and ceramics, X-ray energies of more than 10 keV need to be used. All these setups require X-ray optics for either direct imaging of the object in question or for preparing a magnified projection. The P05 Imaging Beamline for X-ray micro- and nanotomography is situated at the newly refurbished PETRA III 3rd generation storage ring at DESY. A dedicated experiment for X-ray nanotomography at higher energies was built in one of the two experimental hutches. An X-ray optics concept tailored for this experiment was specified and an accompanying mechanics concept was devised. Based on these concepts, the experiment was designed and installed. In addition to testing the nanotomography experimental components, the beamline front end was commissioned and the influence of these components on the nanotomography experiment was investigated. Higher harmonics from the undulator and monochromator as well as beam position drifts caused by mechanical drifting the monochromator were investigated to analyze their influence on the nanotomography. The X-ray optics were tested in detail and an operational setup was achieved for both the X-ray microscopy and the cone-beam setup. The achieved resolution of the hard X-ray microscope is better than 100 nm line and space. Nanotomographies were performed on a nanoporous gold sample and a photonic glass sample. Image correlation and correction allowed to perform a reconstruction of the photonic glass sample using a filtered backprojection algorithm. The packing fraction <eta> of the photonic glass could be successfully extracted from the 3D-dataset.