Patent ID: 8624208

Claim:
An extreme ultraviolet light generation system used with a laser apparatus and connected to an external device so as to supply extreme ultraviolet light thereto, the extreme ultraviolet light generation system comprising: a chamber provided with at least one inlet through which a laser beam is introduced thereinto; a target supply unit provided to the chamber and configured for supplying a target material to a predetermined region inside the chamber; a discharge pump connected to the chamber; a collector mirror disposed inside the chamber and configured for collecting extreme ultraviolet light emitted when the target material is irradiated with the laser beam in the predetermined region inside the chamber; an etching gas introduction unit provided to the chamber through which etching gas passes, the etching gas being introduced to etch debris of the target material which is emitted when the target material is irradiated with the laser beam inside the chamber and adheres to the collector mirror; and at least one temperature control mechanism configured for controlling a temperature of the collector mirror, wherein the etching gas introduction unit is provided with at least one opening oriented toward a reflective surface of the collector mirror.