The present invention makes it possible to obtain a multilayer film
reflective mirror 61 comprising a first multilayer film 67 which is
formed by alternately laminating Mo layers 671 and Si layers 673 on a
substrate 63, and a second multilayer film 65 which is formed on top of
the first multilayer film 67, and which is formed by alternately
laminating Mo layers 651 and Si layers 653, wherein the thickness of the
Mo layers in the first multilayer film is substantially equal to or
smaller than the thickness of the Mo layers in the second multilayer
film, and the ratio of the thickness of the Mo layers to the thickness of
the Si layers in the first multilayer film is different from the ratio of
these thicknesses in the second multilayer film. As a result, a
multilayer film reflective mirror with a low internal stress in which a
drop in the reflectivity is suppressed can be obtained.