INDIVIDUAL BEAM DETECTOR FOR MULTIPLE BEAMS MULTI-BEAM IRRADIATION APPARATUS AND INDIVIDUAL BEAM DETECTION METHOD FOR MULTIPLE BEAMS

摘要

An objective of the present invention is to provide an individual beam detector for multiple beams, which is capable of preventing clogging of a fine hole caused by impurities in a short period of time, an apparatus having the individual beam detector mounted thereon, and an individual beam detection method for multiple beams. According to an aspect of the present invention, the individual beam detector for multiple beams includes: a thin film having a film thickness which enables transmittance of the multiple beams, and having a through hole formed therein, which has a size smaller than a pitch between the beams of multiple beams and larger than the diameter of the beams; a support not only supporting the thin film, but also having an opening formed therein under a region including the through hole in the thin film, and formed with a width size of the opening for a circumferential temperature of the through hole in the thin film to become a temperature higher than an evaporation temperature of impurities attached to the circumference of the through hole when the multiple beams are irradiated onto the thin film; and a sensor disposed at a distance from the thin film to obtain a detection value having a contrast distinguishable from a detection object beam passing through the through hole of the thin film.