An extreme ultraviolet (EUV) lithography system includes a vane bucket module. The vane bucket module includes a temperature adjusting pack and a collecting tank inserted into the temperature adjusting pack. The temperature adjusting pack has a plurality of inlets. The collecting tank has a cover and the cover includes a plurality of through holes. The inlets of the temperature adjusting pack are aligned with the through holes of the cover. Thicknesses of edges of the cover is different from a thickness of a center of the cover.