Abstract:
By the method of ion-beam shape correction, a small-sized ion beam formed a non axisymmetric aspherical profile of the collector surface for an extreme ultraviolet radiation source TEUS-S100 with a numerical aperture of NA = 0.25, PV on the surface is – 36.3 $\mu$m microns, the surface shape accuracy by standard deviation is – 0.074 $\mu$m microns, which allowed to obtain a focusing spot with a width of 300 $\mu$m at half-height. To solve the problem, the technological ion source KLAN-53M was upgraded the flat ion-optical system was replaced with a focusing one. The ion-optical system consisting of a pair of concave grids with a radius of curvature of 60 mm provided the following parameters of the ion beam: the ion current is 20 mA, the width at half height is 8.2 mm at a distance of 66 mm from the cutoff of the ion source.
Keywords:EUV radiation, ion beam correction, ion source, aspherics.