Development of a local vacuum system for focused ion beam machining.

A local vacuum system for focused ion beam (FIB) processing, with a workpiece set in the air, has been developed. The local vacuum apparatus had a double-wall cylinder structure, used a differential exhaust, and each cylinder was connected to a vacuum exhaust pump. When the gap between the workpiece and the apparatus was 10 microm, the pressure of beam line in the machining head achieved 2.