An EUV lithographic apparatus includes a wafer stage and a particle removing assembly for cleaning a wafer for an extreme ultraviolet (EUV) lithographic apparatus. The wafer stage includes a measurement side and an exposure side. The particle removing assembly includes particle removing electrodes, an exhaust device and turbomolecular pumps. The particle removing electrodes is configured to direct debris from the chamber by suppressing turbulence such that the debris can be exhausted from the wafer stage to the outside of the processing apparatus. In some embodiments, turbomolecular pumps are turned off in the measurement side of the wafer stage so that an exhaust flow can be guided to an exposure side of the wafer stage. In some embodiments, the speed of voltage rise to the electrodes of the wafer chuck is adjusted.