Patent ID: 8569722
Filing Date: 2013-10-29
Classification: H01S,H05G

Abstract:
1. An extreme ultraviolet light generation apparatus, which generates extreme ultraviolet light by irradiating a target material with a laser pulse based on a trigger signal outputted from an exposure apparatus, comprising: a chamber; a target supply unit configured for outputting a target material into the chamber; a laser apparatus configured for outputting a laser pulse into the chamber; a timer configured for timing; a first storage unit configured for storing a parameter log of burst-outputted extreme ultraviolet light; an EUV light detector configured for detecting energy of the extreme ultraviolet light generated by irradiating the target material with the laser pulse; and a controller configured for outputting a control signal to the laser apparatus and for determining whether or not the trigger signal is a burst signal, in which successive outputting of trigger signals during a predetermined period and resting of outputting the trigger signals after the successive outputting are repeated alternately, based on a temporal interval of the trigger signals measured by the timer, and when the trigger signal is the burst signal executing a burst control in which the control signal is successively outputted to the laser apparatus, wherein the controller switches a learning control based on the parameter log stored in the first storage unit and a feedback control based on energy of a last extreme ultraviolet light detected by the EUV light detector during a period of burst control.