Method for controlling discharge plasma radiation source based on pulsed radiation stabilization, involves determining calibration function if deviation value between statistical value and reference value exceeds preset tolerance range

摘要

A calibration function is determined as mathematical relationship between input quantity values and operating parameter values of extreme UV radiation source (3) to select reference values among operating parameter values. The value of a test variable is measured for each radiation pulse and a statistical value is obtained from values ?[deg] f test variable. A deviation between statistical value and reference value is determined and the deviation value is compared with preset tolerance range. The calibration function is determined again if deviation value exceeds tolerance range.