US Patent 7381951 Charged particle beam adjustment method and apparatus

A charged particle beam adjustment apparatus for tilting an electron beam by a tilt deflector is disclosed. The tilt angle adjustment of the electron beam and the distortion adjustment for correcting the image distortion generated when the electron beam is tilted are conducted on a specified. sample such as a pyramidal sample. The images before and after the tilting are acquired and processed to determine the tilt angle value and the distortion amount. The tilt angle adjustment and the adjustment for correction of the distortion are automated in accordance with a predetermined processing flow.