Multi-electron beam image acquisition apparatus, multi-electron beam inspection apparatus, and multi-electron beam image acquisition method

A multi-electron beam inspection apparatus comprising:

• a stage on which a substrate is to be mounted;
• an emission source configured to emit multiple primary electron beams;
• a first electromagnetic lens configured to focus the multiple primary electron beams to form an image on the substrate;
• a separator configured to separate multiple secondary electron beams, which are emitted from the substrate due to irradiation with the multiple primary electron beams, from the multiple primary electron beams;
• a detector configured to detect the multiple secondary electron beams having been separated;
• a second electromagnetic lens configured to be controlled to variably adjust a peak position of a magnetic field distribution in a direction of a trajectory central axis of the multiple secondary electron beams, and to focus the multiple secondary electron beams to form an image on either one of a detection surface of the detector and a position conjugate to the detection surface;
• and
• a comparison circuit configured to compare an image acquired by detecting the multiple secondary electron beams by the detector with a reference image, wherein
• the first electromagnetic lens focuses, to form an image, the multiple secondary electron beams in a state before being separated from the multiple primary electron beams, and
• the second electromagnetic lens is arranged between the separator and an image forming point on which the multiple secondary electron beams are focused by the first electromagnetic lens.

A multi-electron beam image acquisition method comprising:

• emitting multiple primary electron beams;
• focusing, by a first electromagnetic lens, the multiple primary electron beams to form an image on a substrate mounted on a stage;
• separating, by a separator, multiple secondary electron beams, which are emitted from the substrate due to irradiation with the multiple primary electron beams, from the multiple primary electron beams;
• detecting, by a detector, the multiple secondary electron beams having been separated;
• and
• focusing the multiple secondary electron beams to form an image on either one of a detection surface of the detector and a position conjugate to the detection surface, by using a second electromagnetic lens which can be controlled to variably adjust a peak position of a magnetic field distribution in a direction of a trajectory central axis of the multiple secondary electron beams, wherein
• the first electromagnetic lens focuses, to form an image, the multiple secondary electron beams in a state before being separated from the multiple primary electron beams, and
• the second electromagnetic lens is arranged between the separator and an image forming point on which the multiple secondary electron beams are focused by the first electromagnetic lens.