A method for generating extreme ultraviolet (EUV) radiation includes introducing a fuel droplet; applying a first laser beam to strike the fuel droplet at a location to generate EUV radiation and form a movable debris of the fuel droplet; and forming an energy field proximal to the location of the first laser beam strike to trap the movable debris. An EUV radiation source includes a fuel droplet generator, a first laser, a collector and an energy field. The fuel droplet generator is configured to provide a fuel droplet. The first laser is configured to generate a first laser beam to strike the fuel droplet at a location to generate EUV radiation and form a movable debris. The collector is configured to reflect the EUV radiation. The energy field is configured to trap the movable debris, wherein the energy field is proximal to the location of the first laser beam strike.