ELLIPTICITY SETTING DEVICE OF LIGHT BEAM EXPOSURE SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide the ellipticity setting device of the light beam exposure system which can correct the light beam of the light beam exposure system that is scanned by the switching of an AOM (acoustooptic element) and the rotation of a polygon into an ideal circular shape. SOLUTION: This light beam exposure system draws a pattern on a reticle 8r) by scanning a polygon 7 while switched by the acoustoopic element 3. In this case, the device is equipped with a beam elliptic shaping optical system mechanism part which makes the light beam from a light source 2 elliptic to specific ellipticity and an elliptic axis rotary optical system mechanism part which rotates the elliptically shaped light beam on the optical axis by a specific tilt angle and makes it incident on the acoustooptic element 3. The light beam is made elliptic again in the opposite direction by the scanning of the acoustooptic element 3 and polygon 7 by passing through the said mechanism parts, and then sectioned nearly circularly when irradiating the reticle 8r).