Focused ion beam apparatus and method for irradiating focused ion beam

摘要

In an optical system, the total optical path length from the emitter tip of an ion source (1) to the surface of a sample (10) is in the range of from 300 to 450 mm, the distance from the ion source to the centre of a condenser lens (2) is in the range of from 15 to 45 mm, and the distance from the centre of an objective lens (8) to the sample is in the range of from 10 to 40 mm. The optical system is installed in a focused ion beam apparatus in order to realise milling of fine elements to high accuracy at high speed, image observation with high resolution in failure analysis and process evaluation of fine elements such as semiconductors. <IMAGE>