Greiwe Gerd-Hendrik, Balogh Zoltan, Schmitz Guido
Institute of Materials Physics, University of Münster, Wilhelm-Klemm-Str. 10, D-48149 Münster, Germany.
Institute of Material Science, University of Stuttgart, Heisenberg Straße 3, D-70569 Stuttgart, Germany.
Ultramicroscopy. 2014 Jun;141:51-5. doi: 10.1016/j.ultramic.2014.03.007. Epub 2014 Mar 21.
Li-doped silicate and borate glasses are electronically insulating, but provide considerable ionic conductivity. Under measurement conditions of laser-assisted atom probe tomography, mobile Li ions are redistributed in response to high electric fields. In consequence, the direct interpretation of measured composition profiles is prevented. It is demonstrated that composition profiles are nevertheless well understood by a complex model taking into account the electronic structure of dielectric materials, ionic mobility and field screening. Quantitative data on band bending and field penetration during measurement are derived which are important in understanding laser-assisted atom probe tomography of dielectric materials.
