Patent ID: 7034314
Filing Date: 2006-04-25
Classification: B82Y,G21K,H01J

Abstract:
1. A projection apparatus for projecting a pattern formed on a mask held by a mask stage onto a substrate, said projection apparatus comprising: a charged particle beam source which emits a charged particle beam; an irradiation system which has a shaping system for shaping the charged particle beam to have an arcuate cross-section and which irradiates the mask with the arcuate cross-sectional charged particle beam; a projection optical system which projects the pattern onto the substrate, said projection optical system including a first unit having first and second magnetic lenses; and a controller arranged to move a principal plane of said first unit in a direction of an optical axis of said projection optical system so that an image distortion of said projection optical system is corrected, wherein said controller changes a distribution of an axial magnetic field generated by said first unit in the direction of the optical axis of said projection optical system to move the principal plane of said first unit by changing a ratio of currents to be respectively supplied to said first and second magnetic lenses, so that third-order image distortion and fifth-order image distortion substantially cancel each other.