Method of measuring magnetic field and charged particle beam apparatus using the same method.

摘要

A charged particle beam (12a, 12b) is transmitted through a specimen (14) for producing an irregular pattern as a first image. Further, a magnetic field to be measured (16) is arranged in space where a charged particle beam is passed between the specimen and an image plane thereby to produce a second image having an irregular pattern as in the foregoing case. The first image and the second image are processed to produce the deflection angle of the charged particle beam due to the magnetic field. This deflection angle is extracted from the entire positions of a cross section of the space where measurement is desired, thereby constructing projection data of a magnetic field by a charged particle beam. Furthermore, the magnetic field to be measured is rotated and the above-mentioned processing is performed from each direction to construct projection data. The projection data thus obtained and the computer tomography technique are used to determine a magnetic field at each point in space. <IMAGE>