LASER PLASMA EUV LIGHT SOURCE, TARGET MEMBER, PRODUCTION METHOD FOR TARGET MEMBER, TARGET SUPPLYING METHOD, AND EUV EXPOSURE SYSTEM

摘要

Targets (1) are jetted with their disc directions aligned from a nozzle (2) having a slit-form opening. Targets (1) are carried along on a gas flow. In this example, He gas is used. Targets (1) may be jetted by vibrating the nozzle (2) with a piezoelectric element. Since the outside of the nozzle (2) is kept highly vacuum, targets (1) jetted from the nozzle (2) reach a laser beam irradiation position with their postures kept as they are. In synchronization with the supply of targets (1), a pulse laser beam (5) from a Nd:YAG laser light source (4) is condensed at a lens (3) and applied to targets (1). The spot diameter of laser is 1mm, the same as the diameter of a target (1), and its thickness is up to 1000nm. Accordingly, almost all targets are turned into plasma, thus preventing debris from occurring and enhancing a conversion efficiency.