MULTILAYER REFLECTION MIRROR AND EUV EXPOSURING DEVICE

摘要

PROBLEM TO BE SOLVED: To accurately obtain necessary quantities with a measuring method for the shape of reflection wave front by removing only necessary quantity of multilayer film surface for specifically shaping the reflection surface of a multilayer reflection mirror. SOLUTION: The wavelength of light used in the measurement is set to be that practically used by introducing in the multilayer film reflection mirror. Using a diffraction element in a measurement system as an optical element performs the measurement.