Why do We Need a High Performance Position Sensitive Detector in Atom Probe Tomography?

Summary form only given. We have studied the correlation between field evaporated atoms during an atom probe tomography experiment. The evaporated atoms have been shown to be highly correlated both in time and in space. This correlation can be explained by the dynamic distribution of the electric field at the surface of the sample. The distance of correlation between successively evaporated atoms corresponds to the mean size of this zones and the time of correlation corresponds to the mean time necessary to evaporate the entire zone. These zones are most likely to correspond to atomic terraces. These strong correlations in time and in space are the sources of high stresses for position sensitive detectors. A detector with high spatial and time resolving power is required in order to obtain quantitative composition measurement in atom probe tomography