Patent Number: 
Section: abstract

The present invention enables the same target to be precisely machined and observed in a short time when a focal distance of a charged particle beam is changed or if the focal distances of charged particle beams are not equal on a sample. The present invention provides a charged particle beam application apparatus having a stage device used to move a sample in at least three axial directions, a charged particle beam optical system having an optical axis inclined from a surface of the sample to irradiate the sample with a charged particle beam, and a display device that displays an image formed by the charged particle beam optical system, the apparatus including a correction table indicating a relationship between both focal distance and optical conditions for said charged particle beam optical system and a position of the sample, and an arithmetic section that calculates the position of the sample, the arithmetic section calculating the amount of correction for the position of the sample so that when the focal distance of the charged particle beam changes, a position of a target on the sample is placed in the center of a visual field of a screen of the display device.