Apparatus and methods for charged-particle-beam microlithography exhibiting reduced aberrations caused by beam deflection to correct errors in stage-position control

摘要

Apparatus and methods are disclosed for performing charged-particle-beam (CPB) microlithography in which aberrations arising from increased magnitudes of beam deflection are suppressed by making respective corrections for stage-position control errors. A CPB microlithography apparatus includes an image-positioning deflector that imparts a magnitude of deflection to the patterned beam appropriate for correcting stage-position-control errors. The magnitudes of correction are recorded in a memory of a statistical computer for each subfield of the pattern. Upon performing an exposure of a specified range (e.g., stripe) of the pattern containing multiple subfields, the correction values are statistically processed and trends (e.g., shifts in a specific direction) are analyzed. When exposing the next stripe of the pattern, the position of the wafer stage is adjusted in anticipation of any trends in required corrections such that the amounts of deflection to be performed by the image-positioning deflector are as small as possible within a predetermined range.