METHOD FOR CORRECTING THE WAVELENGTH CHANGE OF THE LIGHT IN THE EXPOSURE SYSTEM

摘要

A method for correcting a wavelength change of light in an exposure system is provided to correct illumination conditions and a changed wavelength width by sensing a change of wavelength widths of light approaching a wafer. A loading process is performed to load a reticle including a plurality of patterns on a reticle stage(S10). An irradiation process is performed to irradiate light of a light source on a reticle by using an illumination unit positioned at a front end of the reticle(S20). A measurement process is performed to measure an intensity value of the light applied to a substrate stage through the reticle and a projection part positioned at a rear end of the reticle(S30). A comparison process is performed to compare the measured light intensity value with a predetermined initial light intensity value(S40).