Oberdorfer secures place in International Scholar Research Exposition
The Department of Materials Science and Engineering congratulates Chris Oberdorfer, MSE postdoctoral visiting scholar, for being recognized at the Ohio State's 14th annual International Research Exposition. Hosted by the Office of International Affairs, "this exposition recognizes scholars' presence on campus and the significant contribution they make to the university and global community"¹. Chris Oberdorfer comes to Ohio State as a visiting scholar from University of Stuttgart in his native country of Germany. Of the 1,800 international visiting scholars at Ohio State, 34 finalists were chosen to create research posters that are being displayed in Bricker Hall until the end of 2019. Oberdorfer is the first MSE postdoc to be recognized at this exposition since 2013. His research is detailed below.
Research title: Atomistic Simulation of Field Evaporation in Atom Probe Tomography
Issue being addressed in his research
Atom Probe Tomography is a nano-analytic characterization technique in materials science. The approach uses a combination of an applied high-voltage and short laser pulses to rip off atoms from the surface of needle-shaped samples atom by atom. Information about the atoms are recorded by a detector. By means of sophisticated computer-based post processing of the data, 3D atomic maps of the original samples are reconstructed. Chris's research focuses on improving these reconstructions.
Research methodology
Chris developed and applied an atomistic computer model of the field evaporation process that is able to predict atom probe experiments. The model calculates the distribution of the electric field distribution about the considered sample and uses that information to determine forces acting on the surface atoms. Up to a certain amount, such an extra force can be balanced by the internal bonding between the atoms. Once a critical threshold is exceeded the atom is pulled off the surface.
Purpose/rationale and implications of his research
Properties of modern materials increasingly rely on controlling the chemical composition and atomic structure at short length scales (e.g. in semiconductors). This requires powerful analytical techniques to analyze materials at these short length scales. Atom Probe is one of only a few available techniques that provide the necessary capabilities. Further improvement of these capabilities will allow for better materials in future technological applications.
