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介绍了一台使用液态金属离子源的二级透镜亚微米聚焦离子束系统。系统使用了可以微动的针尖以及电可调现场可变束径束流技术，在加速电压为１５ｋｅＶ，束流为３０ｐＡ时，束径可达到１００ｎｍ。在系统设计时，提出了逐级可测性原则，并在设计结构时同时设计一套科学的调整方案，使二级透镜系统的对中调整更加迅速可靠。探讨了一种新的对中判断方法，称为漂移法，就是在保证光阑孔和透镜光轴合轴很好的情况下，聚焦电压偏移一定量时像点位置的漂移最小时物点离轴最近。漂移法比常用的束径最小法更加灵敏、可靠。
A two-stage sub-micron focused ion beam system using a liquid metal ion source is presented. The system uses a micro-motionable tip and electrically adjustable field variable beam-beam technology with a beam diameter of up to 100 nm at an accelerating voltage of 15 keV and a beam of 30 pA. In system design, the principle of step-by-step testability is proposed. At the same time, a set of scientific adjustment scheme is designed in the design of the structure so that the alignment of the secondary lens system can be adjusted more quickly and reliably. In this paper, a new method for determining the centering is proposed, which is called drift method. When the focal point of the aperture and lens is well aligned, Close to the axis. Drift method is more sensitive and reliable than the common minimum diameter method.