Patent ID: 6313474
Filing Date: 2001-11-06
Classification: H01J

Abstract:
A method of measuring distribution of a beam of charged particles, applied to an apparatus in which a workpiece is irradiated with the beam of charged particles while the workpiece is mechanically reciprocated along Y-axis and while the beam of charged particles proceeding along Z-axis substantially perpendicular to Y-axis reciprocates and conducts scanning electromagnetically, and in which a tilt angle formed between a surface of the workpiece and the Y-axis can be set at a value more than 0.degree., the method of measuring distribution of beam of charged particles comprising the steps of:measuring a first current density distribution in the scanning direction of the beam of charged particles at a first position on Z-coordinate and also measuring a second current density distribution in the scanning direction of the beam of charged particles at a second position on Z-coordinate; andfinding a current density distribution in the scanning direction of the beam of charged particles at an arbitrary position on Z-coordinate by the method of interpolation or extrapolation by using the first and the second current density distribution.