title: An analytical model accounting for tip shape evolution during atom probe analysis of heterogeneous materials.
abstract: An analytical model describing the field evaporation dynamics of a tip made of a thin layer deposited on a substrate is presented in this paper. The difference in evaporation field between the materials is taken into account in this approach in which the tip shape is modeled at a mesoscopic scale. It was found that the non-existence of sharp edge on the surface is a sufficient condition to derive the morphological evolution during successive evaporation of the layers. This modeling gives an instantaneous and smooth analytical representation of the surface that shows good agreement with finite difference simulations results, and a specific regime of evaporation was highlighted when the substrate is a low evaporation field phase. In addition, the model makes it possible to calculate theoretically the tip analyzed volume, potentially opening up new horizons for atom probe tomographic reconstruction.
authors.affiliation: Groupe de Physique des Matériaux, UMR 6634 CNRS, Université et INSA de Rouen, 76801 St Etienne du Rouvray, France. Electronic address: Nicolas.rolland1@univ-rouen.fr.
authors.forename: N
authors.initials: N
authors.lastname: Rolland
authors.affiliation: Cameca Instruments, Inc., 5500 Nobel Drive, Madison, WI 53711, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Larson
authors.affiliation: Cameca Instruments, Inc., 5500 Nobel Drive, Madison, WI 53711, USA.
authors.forename: B P
authors.initials: BP
authors.lastname: Geiser
authors.affiliation: Groupe de Physique des Matériaux, UMR 6634 CNRS, Université et INSA de Rouen, 76801 St Etienne du Rouvray, France.
authors.forename: S
authors.initials: S
authors.lastname: Duguay
authors.affiliation: Groupe de Physique des Matériaux, UMR 6634 CNRS, Université et INSA de Rouen, 76801 St Etienne du Rouvray, France.
authors.forename: F
authors.initials: F
authors.lastname: Vurpillot
authors.affiliation: Groupe de Physique des Matériaux, UMR 6634 CNRS, Université et INSA de Rouen, 76801 St Etienne du Rouvray, France.
authors.forename: D
authors.initials: D
authors.lastname: Blavette
keywords: Atom probe tomography; Field evaporation; Simulation; Tip shape evolution