GPM UMR CNRS 6634-Université de Rouen, Avenue de l'Université-B.P. 12, 76801 Saint Etienne Du Rouvray Cedex, France.
Ultramicroscopy. 2013 Sep;132:152-7. doi: 10.1016/j.ultramic.2012.12.007. Epub 2012 Dec 12.
A model devoted to the modelling of the field evaporation of a tip is presented in this paper. The influence of length scales from the atomic scale to the macroscopic scale is taken into account in this approach. The evolution of the tip shape is modelled at the atomic scale in a three dimensional geometry with cylindrical symmetry. The projection law of ions is determined using a realistic representation of the tip geometry including the presence of electrodes in the surrounding area of the specimen. This realistic modelling gives a direct access to the voltage required to field evaporate, to the evolving magnification in the microscope and to the understanding of reconstruction artefacts when the presence of phases with different evaporation fields and/or different dielectric permittivity constants are modelled. This model has been applied to understand the field evaporation behaviour in bulk dielectric materials. In particular the role of the residual conductivity of dielectric materials is addressed.
本文提出了一种专门用于模拟尖端场蒸发的模型。该方法考虑了从原子尺度到宏观尺度的长度尺度的影响。在具有圆柱对称性的三维几何形状中，在原子尺度上对尖端形状的演化进行建模。使用包括样品周围区域存在电极的尖端几何形状的真实表示来确定离子的投影定律。这种现实的建模可以直接访问场蒸发所需的电压、显微镜中不断变化的放大倍数以及在模拟具有不同蒸发场和/或不同介电常数的相时对重建伪影的理解。该模型已应用于理解体介电材料的场蒸发行为。特别是，解决了介电材料残余电导率的作用。
