ILLUMINATION OPTICAL DEVICE, ALIGNER COMPRISING THE SAME, AND METHOD FOR FABRICATING MICRODEVICE

摘要

PROBLEM TO BE SOLVED: To provide an illumination optical device in which the size can be reduced while suppressing coherence of a light source, an aligner comprising the illumination optical device, and a method for fabricating a microdevice comprising the aligner. SOLUTION: Coherent light from a light source 10 is split by a half-mirror 21 and one part advances through an optical integrator system 40. The other part advances on a circulation optical path having an optical path length difference shorter than the coherence distance of the coherent light. It is then split again by the half-mirror 21 and the process is repeated. A deflection element 23 is a transparent optical element for deflecting light in a specified direction. Lights having a specified optical path length difference and a specified deflection angle and advancing through the optical integrator system 40 are mixed and passed through a light introduction system 30 before illuminating a reticle 60.