Method for correction for chromatic aberration and exposure apparatus using the same

摘要

Disclosed is an exposure apparatus used in a photolithographic process in fabrication of semiconductor devices. More particularly, in the exposure apparatus using an excimer laser, the beam splitter, mirror and lens for correction for chromatic aberration are combined in the alignment optical system. Furthermore, a mirror is disposed at the opposite side of the image pickup camera of the alignment key by way of the beam splitter.