Radiation source for extreme ultraviolet radiation, e.g. for use in lithographic projection apparatus

摘要

A radiation source of a radiation system of a lithographic projection apparatus includes a primary jet nozzle 10 constructed and arranged to eject a primary gas or liquid 15 in a first direction; a supply 11 for the primary gas or liquid which is to be brought into an excited energy state when ejected from the primary nozzle 10 and is to emit ultraviolet electromagnetic radiation when falling back to a lower energy state; an exciting mechanism such as a laser 30 for bringing the primary gas or liquid into the excited energy state; a secondary jet nozzle 20 constructed and arranged to eject a secondary gas or liquid 25 in the first direction and positioned aside, possibly enclosing, the primary jet nozzle 10; and a supply 21 for the secondary gas or liquid.