A device is disclosed herein which may comprise a chamber, a source providing a stream of target material droplets delivering target material to an irradiation region in the chamber along a path between a target material release point and the irradiation region, a gas flow in the chamber, at least a portion of the gas flowing in a direction toward the droplet stream, a system producing a laser beam irradiating droplets at the irradiation region to generate a plasma producing EUV radiation, and a shroud positioned along a portion of said stream, said shroud having a first shroud portion shielding droplets from said flow and an opposed open portion.