Ion-optical imaging system

摘要

A system for ion-beam imaging of a structure of a mask on a wafer has a two-lens set between the mask and the wafer which is one of the following combinations: (a) two accelerating Einzel lenses; (b) an accelerating immersion lens and a decelerating immersion lens wherein the accelerating immersion lens is the first collecting lens following the mask; (c) an accelerating immersion lens and a decelerating asymmetric Einzel lens wherein the accelerating immersion lens is the first collecting lens following the mask; (d) an accelerating asymmetric Einzel lens and a decelerating immersion lens wherein the accelerating asymmetric Einzel lens is the first collecting lens following the mask; and (e) an accelerating asymmetric Einzel lens and a decelerating asymmetric Einzel lens wherein the accelerating asymmetric Einzel lens is the first collecting lens following the mask.