Patent ID: 8026482

Claim:
A charged particle beam apparatus comprising: a charged particle beam optical system that irradiates a specimen housed in a specimen chamber with a primary charged beam, detects a secondary charged particle beam generated from the specimen, and outputs a signal of a detection result; first potential measuring means measures potentials on a surface of the specimen at a plurality of locations on a line segment including a center location of the specimen before irradiation of the specimen with the primary charged beam during transfer of the specimen towards a specimen stage of the charged particle beam optical system; height measurement means, which measures a height of the surface of the specimen on the specimen stage before irradiation of the specimen with the primary charged beam; and a control unit that controls the charged particle beam optical system on a basis of height information obtained by height measurement means and potential information obtained by the first potential measurement means, wherein the control unit: estimates a potential distribution for the line segment by a first interpolation on a basis of the potentials measured by the first potential measuring means before irradiation of the specimen with the primary charged beam; and estimates a potential at any location on the specimen by a second interpolation in a circumferential direction of the specimen on a basis of the potential distribution estimated along the line segment before irradiation of the specimen with the primary charged beam.