Improvement of fabrication precision of focused ion beam by introducing simultaneous electron beam

The introduction of electron beam (EB) brings features of both simultaneous observation of ion milling process and improvement of ion-milling accuracy in a dual beam system consisting of focused ion beam (FIB) and scanning electron microscope (SEM). The experiments reveal that simultaneous EB can also decrease the fabrication line width significantly during the ion milling process. Considering the Coulomb interaction between ions and electrons, the effect of simultaneous EB on the diameter of FIB in the course of milling was studied by numerical simulation. Both experiments and simulation indicate that the achievable fabrication line width can be dramatically reduced under appropriate conditions by introducing EB. It provides a convenient and effective way to improve the fabrication precision in the SEM-FIB dual beam system.