A low voltage scanning electron microscope is disclosed, which includes: an electron source configured to generate an electron beam; an electron beam accelerator configured to accelerate the electron beam; a compound objective lens configured to converge the electron beams accelerated by the electron beam accelerator; a deflection device arranged between the inner wall of the magnetic lens and the optical axis of the electron beam and configured to deflect the electron beam; a detection device comprising a first sub-detection device for receiving secondary and backscattered electrons from the specimen, a second sub-detection device for receiving backscattered electrons, and a control device for changing the trajectories of the secondary electrons and the backscattered electrons; an electrostatic lens comprising the second sub-detection device, a specimen stage, and a control electrode for reducing the moving speed of the electron beam and changing the moving directions of the secondary and the backscattered electrons.

An immersion objective lens is configured below a stage such that multiple detectors can be configured above sample for large beam current application, particularly for defect inspection. Central pole piece of the immersion objective lens thus can be provided that a magnetic monopole-like field can be provided for electron beam. Auger electron detector thus can be configured to analyze materials of sample in the defect inspection.

An immersion objective lens is configured below a stage such that multiple detectors can be configured above sample for large beam current application, particularly for defect inspection. Central pole piece of the immersion objective lens thus can be provided that a magnetic monopole-like field can be provided for electron beam. Auger electron detector thus can be configured to analyze materials of sample in the defect inspection.

A method for operating a particle beam apparatus. An objective lens current may be swept, and a property of a deflection unit and/or of an aperture unit may be set while the objective lens current is swept. Setting the property may implemented in such a way that either an image of the object displayed on a display device does not move or any such movement of the displayed image has a minimal deflection. Moreover, the operating voltage of a beam generator may be swept and the object may be aligned by means of a specimen stage. While the operating voltage is swept, the specimen stage may be moved into an aligned position in such a way that either the image of the object displayed on the display device does not move or any such movement of the displayed image has a minimal deflection.

Provided is a multiple electron beam inspection apparatus including: an irradiation source irradiating a substrate with multiple electron beams; a stage on which is cable of mounting the substrate; an electromagnetic lens provided between the irradiation source and the stage, the electromagnetic lens generating a lens magnetic field, the multiple electron beams being capable of passing through the lens magnetic field; an electrostatic lens provided in the lens magnetic field, the electrostatic lens including a plurality of through-holes and a plurality of electrodes, the plurality of through-holes having wall surfaces respectively, each of the multiple electron beams being capable of passing through the corresponding each of the plurality of through-holes, each of the plurality of electrodes provided on each of the wall surfaces of the plurality of through-holes, at least one of the through-holes provided apart from a central axis of trajectory of the multiple electron beams having a spiral shape; and a power source connected to the electrodes.

Provided is a multiple electron beam inspection apparatus including: an irradiation source irradiating a substrate with multiple electron beams; a stage on which is cable of mounting the substrate; an electromagnetic lens provided between the irradiation source and the stage, the electromagnetic lens generating a lens magnetic field, the multiple electron beams being capable of passing through the lens magnetic field; an electrostatic lens provided in the lens magnetic field, the electrostatic lens including a plurality of through-holes and a plurality of electrodes, the plurality of through-holes having wall surfaces respectively, each of the multiple electron beams being capable of passing through the corresponding each of the plurality of through-holes, each of the plurality of electrodes provided on each of the wall surfaces of the plurality of through-holes, at least one of the through-holes provided apart from a central axis of trajectory of the multiple electron beams having a spiral shape; and a power source connected to the electrodes.

According to one aspect of the present invention, an electron beam image acquisition apparatus includes a first electrostatic lens group correcting a shift amount of a focus position of the primary electron beam from the reference position on the surface of the substrate occurring according to movement of the stage, and a plurality of variation amounts of the primary electron beam on the surface of the substrate by correcting the shift amount of the focus position of the primary electron beam; and a second electrostatic lens group correcting a plurality of variation amounts of an image of a secondary electron beam being emitted from the substrate by irradiating the substrate with the primary electron beam corrected by the first electrostatic lens group, the secondary electron beam passing through at least one electrostatic lens of the first electrostatic lens group.

According to one aspect of the present invention, an electron beam image acquisition apparatus includes a first electrostatic lens group correcting a shift amount of a focus position of the primary electron beam from the reference position on the surface of the substrate occurring according to movement of the stage, and a plurality of variation amounts of the primary electron beam on the surface of the substrate by correcting the shift amount of the focus position of the primary electron beam; and a second electrostatic lens group correcting a plurality of variation amounts of an image of a secondary electron beam being emitted from the substrate by irradiating the substrate with the primary electron beam corrected by the first electrostatic lens group, the secondary electron beam passing through at least one electrostatic lens of the first electrostatic lens group.

An electromagnetic compound lens may be configured to focus a charged particle beam. The compound lens may include an electrostatic lens provided on a secondary optical axis and a magnetic lens also provided on the secondary optical axis. The magnetic lens may include a permanent magnet. A charged particle optical system may include a beam separator configured to separate a plurality of beamlets of a primary charged particle beam generated by a source along a primary optical axis from secondary beams of secondary charged particles. The system may include a secondary imaging system configured to focus the secondary beams onto a detector along the secondary optical axis. The secondary imaging system may include the compound lens.

An electromagnetic compound lens may be configured to focus a charged particle beam. The compound lens may include an electrostatic lens provided on a secondary optical axis and a magnetic lens also provided on the secondary optical axis. The magnetic lens may include a permanent magnet. A charged particle optical system may include a beam separator configured to separate a plurality of beamlets of a primary charged particle beam generated by a source along a primary optical axis from secondary beams of secondary charged particles. The system may include a secondary imaging system configured to focus the secondary beams onto a detector along the secondary optical axis. The secondary imaging system may include the compound lens.