Slit lens arrangement for particle beam e.g. for electron or ion beam lithography, uses 2 combined lenses each having electrostatic cylindrical lens and magnetic quadrupole lens

摘要

The slit lens arrangement has 2 combined lenses (1,2) positioned one after the other, each having an electrostatic cylindrical lens (4,5) and a magnetic quadrupole lens (6,7), aligned with their optical axes parallel to one another. The aperture plane (8) of the overall arrangement lies between the 2 combined lenses, with its centre axis defining a point (11) to which the combined lenses are asymmetrical, the optical axis of the quadrupole lenses of the combined lenses displaced in diamtric opposition for adjusting the image size.