METHOD AND APPARATUS FOR CORRECTING ERRORS IN AN EUV LITHOGRAPHY SYSTEM

摘要

The invention relates to a method for correcting a local surface defect (430, 440, 530, 540) of a reflective optical element (170, 171, 172, 173, 74, 175, 200, 300, 400, 500, 700, 800) of an extreme ultraviolet lithography system (100) comprises the steps of analyzing the local surface defect (430, 440, 530, 540), correcting the local surface defect (430, 440, 530, 540) by focusing femto- or picosecond light pulses of a laser system (600) onto positions of the local surface defect (430, 440, 530, 540), and verifying that a wave front sensor (190) associated with the extreme ultraviolet lithography system (100) can no longer detect the local surface defect (430, 440, 530, 540).