Effect of the subsidiary electrode in a newly developed source lens structure of the microcolumn

Abstract

A subsidiary electrode was introduced between the extractor and anode in our newly developed source lens design of a micro electron column to improve the probe beam characteristics. At the same field enhancement factor of 3.95, the probe beam current showed a drastic increase compared to that of the conventional source lens structure. The design parameters of the newly developed source lens structure and the equipotential line distribution are presented with simulation results.