P4-19: Tracing backscattered electrons in full energy range

It is critically important to know backscattered electron (BSE) trajectories and current density in electron beam lithography tools, where a 50 keV electron beam is incident upon the target plane. The space near the target plane is occupied by closely-spaced optical components and sensors, all prone to surface charging. We have reported previously the results of testing SOURCEBS rev.1.0, a software for tracing BSE´s of known energy value. Recently, we have developed SOURCEBS rev. 4.0. This software takes the full spectrum of BSE energies and initial coordinates from MONSEL, an electron-solid state modeling software program. SOURCEBS rev. 4.0 traces BSE´s with their full energy spectrum in electrostatic and magnetic fields, and computes the BSE current density at user-chosen surfaces.