Portable scanning electron microscope designs

Abstract

Further analysis and simulation of the portable scanning electron microscope proposal based upon the use of permanent magnets is presented. The interaction between the condenser and objective lenses as well as their coupling to different specimen chambers is taken into account. The proposal is also generalised to apply to miniature SEMs as well as to portable SEM columns and can incorporate magnetic screening. In addition, Hall probe measurements were made for the axial field distribution near the pole tip of a test objective lens, and was found to differ from the simulation predictions by less than 5%.