Method for producing radiation

摘要

A method of producing a radiating plasma with an increased flux stability and uniformity is disclosed. The method comprises the steps of (210) generating a primary target by urging a liquid under pressure through a nozzle; (220) directing an energy pre-pulse onto the primary target to generate a secondary target in the form of a gas or plasma cloud; (230) allowing the thus formed secondary target to expand for a predetermined period of time; and (240) directing a main energy pulse onto the secondary target when the predetermined period of time has elapsed in order to produce a plasma radiating X-ray or EUV radiation. The pre-pulse has a beam waist size that is larger, in at least one dimension, than the corresponding dimension of the primary target. <IMAGE>