A charged particle beam exposure method and an apparatus therefor

摘要

A charged particle beam exposure method, wherein a charged particle beam is shaped based on pattern data and the shaped charged particle beam is irradiated to a desired location on a sample, the method comprises the steps of: introducing ozone gas into a chamber through which the charged particle beam is passed, shaped and deflected so as to be irradiated to the desired location; and maintaining the ozone gas concentration in the chamber so that the concentration downstream along the beam is higher than the concentration upstream along the beam. A charge-up drift due to a contamination material from a resist on a wafer can be avoided by the ozone self cleaning. The ozone oxidation does not occure at the upstream chamber where lower ozone consentration but lower contamination.