An improved charged particle beam inspection apparatus, and more particularly, a particle beam inspection apparatus for detecting a thin device structure defect is disclosed. An improved charged particle beam inspection apparatus may include a charged particle beam source to direct charged particles to a location of a wafer under inspection over a time sequence. The improved charged particle beam apparatus may further include a controller configured to sample multiple images of the area of the wafer at difference times over the time sequence. The multiple images may be compared to detect a voltage contrast difference or changes to identify a thin device structure defect.