Coulomb Interactions in a Focused Ion Beam System with a Dynamic Corrected Deflection Field

Abstract

Focused ion beam systems complement conventional processing methods and can be used to prototype and modify a diverse range of nano-devices and sensors. Controllable incident focused ion beam is difficult to obtain due to Coulomb interactions among ions. In this paper, Coulomb interactions of a practical FIB system with a dynamic corrected deflection field are obtained through solving Newton-Lorentz equations in three-dimension (3D). Firstly, the principle of the dynamic correction is analyzed and its 3D realization is given. Secondly, the principle of N-body Monte Carlo method is researched in detail before the source parameter, the 3D field, and the number of N are determined. In the end, the equations are solved by fifth-order Runge-Kutta algorithm and 3D ion trajectory is given for a 30kV FIB through the Mebs software. Simulation results coincide to the experimental those from our Canion 31 + system.