Patent attributes
An extreme ultra violet light source apparatus has a relatively high output for exposure and suppresses the production of debris as much as possible instead of disposing of debris that has been produced. The extreme ultra violet light source apparatus includes: a chamber in which extreme ultra violet light is generated; a target supply unit for supplying solid tin or lithium as a target to a predetermined position within the chamber; a CO2 laser for applying a laser beam based on pulse operation to the target supplied by the target supply unit so as to generate plasma; and a collector mirror having a multilayer film on a reflecting surface thereof, for collecting the extreme ultra violet light radiated from the plasma to output the extreme ultra violet light.