Simulation of specimen structure in atom probe tomography and field electron microscopy

This study presents a mathematical model of a crystal structure of emitter that is the study object of atom probe tomography, field emission electron/ion microscopy and field desorption microscopy. Modern simultaneous use of these methods and its advantages over separate microscopy studies (other than the obvious utility of similarity of samples and mechanisms of constructing the magnified image) is discussed. Intensity of field desorption grows significantly with increase of the surface work function. We present multi-scale modelling of the sample structure: at micro-scale it is an approximation of emitter shape, on meso-scale it's construction of crystallographic faces for application of a semi-empirical regression model of work function distribution, on the nano-scale it's calculation of surface atom coordinates that serve as base data for all the above mentioned levels of detail.