| 摘要 |
An EUV mirror with a substrate and a multilayer arrangement including: a periodic first layer group having N1>1 first layer pairs of period thickness P1 and arranged on a radiation entrance side of the multilayer arrangement; a periodic second layer group having N2>1 second layer pairs of period thickness P2 and arranged between the first layer group and the substrate; and a third layer group having N3 third layer pairs arranged between the first and second layer groups. N1>N2. The third layer group has a mean third period thickness P3 which deviates from an average period thickness PM=(P1+P2)/2 by a period thickness difference &Dgr;P. &Dgr;P corresponds to the quotient of the optical layer thickness (λ/4) of a quarter-wave layer and the product of N3 and cos(AOIM), AOIM being the mean incidence angle for which the multilayer arrangement is designed. |
