Arrangement for generating extreme ultraviolet radiation from a plasma generated by an energy beam with high conversion efficiency and minimum contamination

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.