Line-focusing by means of a quadrupole lens

Abstract

Aperture aberrations affecting the width of the line-focused beam are accurately obtained by using a new shadow-image technique for electrostatic quadrupoles of axial lengths of 20 and 30 mm with an aperture radius of 5 mm. Experimental values are in satisfactory agreement with those calculated by the modified bell-shaped model. The results show that an electrostatic quadrupole lens is very useful for forming fine line patterns. Precision grids, fine gratings and interdigital electrode patterns have been fabricated by using a line-focused beam.