Patent ID: 7599470

Claim:
An arrangement for generating extreme ultraviolet radiation from a plasma generated by energy beam with high conversion efficiency comprising: a pulsed energy beam; a plasma generation chamber, said pulsed energy beam being directed to a location in said chamber where it interacts with a target; a target feed device containing a mixing chamber for generating a mixture of particles of an emission-efficient target material with at least one carrier gas and containing an injection unit for dispensing individually defined target volumes into the plasma generation chamber in a metered manner in order to supply only as much emission-efficient target material to the interaction location as can be converted into radiation by an energy pulse; said target feed device having a gas liquefaction chamber; said target material being supplied to the injection unit as a mixture of solid metal particles in liquefied carrier gas; said injection unit having a droplet generator with a nozzle chamber and a target nozzle for generating a defined droplet size and series of droplets; and means, which are controllable in a frequency-dependent manner and which are triggered by the pulse frequency of the energy beam, being connected to the injection unit for generating a time-controlled series of droplets.