Abstract: An electron beam apparatus is offered which can well detect backscattered electrons or both backscattered electrons and secondary electrons if an electron detector is disposed above an objective lens in the apparatus. The electron beam apparatus has an electron beam source for emitting an electron beam accelerated by a given accelerating voltage, the objective lens for focusing the electron beam emitted from the beam source onto a specimen, scan coils for scanning the focused beam over the specimen, and the electron detector located above the objective lens and provided with a hole permitting passage of the beam. The detector has an electrode for producing an electric field that attracts the electrons produced from the specimen in response to the electron beam irradiation. Correction coils for correcting deflection of the beam caused by the electric field are located below the detector.

Abstract: An electron beam apparatus is offered which can well detect backscattered electrons or both backscattered electrons and secondary electrons if an electron detector is disposed above an objective lens in the apparatus. The electron beam apparatus has an electron beam source for emitting an electron beam accelerated by a given accelerating voltage, the objective lens for focusing the electron beam emitted from the beam source onto a specimen, scan coils for scanning the focused beam over the specimen, and the electron detector located above the objective lens and provided with a hole permitting passage of the beam. The detector has an electrode for producing an electric field that attracts the electrons produced from the specimen in response to the electron beam irradiation. Correction coils for correcting deflection of the beam caused by the electric field are located below the detector.

Abstract: A scanning electron microscope has an electron gun producing the electron beam, an objective lens for sharply focusing the beam onto the specimen, a tilting mechanism for tilting the specimen relative to the beam, and a power supply for applying the negative voltage to the specimen. This microscope further includes a cylindrical shield electrode mounted to surround the electron beam path between the objective lens and specimen. A front-end electrode is insulatively mounted to the front-end portion of the shield electrode that is on the specimen side. An electric potential substantially identical to the electric potential at the polepieces of the objective lens is applied to the shield electrode. An electric potential substantially identical to the potential at the specimen is applied to the front-end electrode.

Abstract: Particle-beam apparatus is realized which is equipped with an aberration corrector capable of controlling the angular aperture of a particle beam after performing aberration correction. The corrector comprises four stages of electrostatic quadrupole elements, two stages of magnetic quadrupole elements for superimposing a magnetic potential distribution analogous to the electric potential distribution created by the two central stages of the electrostatic quadrupole elements, and four stages of electrostatic octupole elements for superimposing an octupole electric potential on the electric potential distribution created by the four stages of electrostatic quadrupole elements. An objective lens is located downstream of the corrector. An objective aperture is located upstream of the corrector. An angular aperture control lens is located downstream of the objective aperture to control the angular aperture of the probe hitting a specimen surface.

Abstract: There is disclosed a scanning electron microscope capable of detecting secondary electrons emitted from a specimen, using a semi-in-lens type objective lens. A voltage is applied to the specimen from a power supply to decelerate the electron beam immediately ahead of the specimen. Secondary electrons produced from the specimen are confined by a magnetic lens field and move spirally upward. The secondary electrons moving upward travel linearly from a location where the magnetic field of the objective lens is weak. Then, the electrons strike first and second conversion electrodes, producing a large amount of secondary electrons. A voltage is applied to the front face of a detector to produce an electric field near the first opening in the inner polepiece. This field directs the secondary electrons toward the detector, where they are detected.

Abstract: A scanning electron microscope has an electron gun producing the electron beam, an objective lens for sharply focusing the beam onto the specimen, a tilting mechanism for tilting the specimen relative to the beam, and a power supply for applying the negative voltage to the specimen. This microscope further includes a cylindrical shield electrode mounted to surround the electron beam path between the objective lens and specimen. A front-end electrode is insulatively mounted to the front-end portion of the shield electrode that is on the specimen side. An electric potential substantially identical to the electric potential at the polepieces of the objective lens is applied to the shield electrode. An electric potential substantially identical to the potential at the specimen is applied to the front-end electrode.

Abstract: A scanning-type instrument is realized which utilizes a charged-particle beam and automates adjustments, if a voltage is applied to the specimen, to thereby provide excellent operational controllability. When a voltage is applied to the specimen, the electron beam would normally defocus. A signal corresponding to the voltage applied to the specimen is supplied to a CPU. An objective lens current is supplied to the coil on the objective lens from a power supply under control of the CPU to refocus the beam. As a result, the beam hitting the specimen is prevented from defocusing if a voltage is applied to the specimen. When the strength of the objective lens is varied, scanning signals to the deflection coils are adjusted in response to the variation. Variation in the magnification of the image and rotation of the image are corrected.

Abstract: There is disclosed a scanning electron microscope capable of detecting secondary electrons emitted from a specimen, using a semi-in-lens type objective lens. A voltage is applied to the specimen from a power supply to decelerate the electron beam immediately ahead of the specimen. Secondary electrons produced from the specimen are confined by a magnetic lens field and move spirally upward. The secondary electrons moving upward travel linearly from a location where the magnetic field of the objective lens is weak. Then, the electrons strike first and second conversion electrodes, producing a large amount of secondary electrons. A voltage is applied to the front face of a detector to produce an electric field near the first opening in the inner polepiece. This field directs the secondary electrons toward the detector, where they are detected.

Abstract: A scanning electron microscope comprises: an electron gun for emitting an electron beam; a system of condenser lenses; scanning coils; and an objective lens having inner and outer magnetic polepieces to form a magnetic field lens below the lower ends of the polepieces. The inner and outer polepieces are provided with mutually communicating bores via which the backscattered electron detector can be withdrawably inserted into the electron beam path within the objective lens.

Abstract: Particle-beam apparatus is realized which is equipped with an aberration corrector capable of controlling the angular aperture of a particle beam after performing aberration correction. The corrector comprises four stages of electrostatic quadrupole elements, two stages of magnetic quadrupole elements for superimposing a magnetic potential distribution analogous to the electric potential distribution created by the two central stages of the electrostatic quadrupole elements, and four stages of electrostatic octupole elements for superimposing an octupole electric potential on the electric potential distribution created by the four stages of electrostatic quadrupole elements. An objective lens is located downstream of the corrector. An objective aperture is located upstream of the corrector. An angular aperture control lens is located downstream of the objective aperture to control the angular aperture of the probe hitting a specimen surface.

Abstract: A scanning-type instrument is realized which utilizes a charged-particle beam and automates adjustments, if a voltage is applied to the specimen, to thereby provide excellent operational controllability. When a voltage is applied to the specimen, the electron beam would normally defocus. A signal corresponding to the voltage applied to the specimen is supplied to a CPU. An objective lens current is supplied to the coil on the objective lens from a power supply under control of the CPU to refocus the beam. As a result, the beam hitting the specimen is prevented from defocusing if a voltage is applied to the specimen. When the strength of the objective lens is varied, scanning signals to the deflection coils are adjusted in response to the variation. Variation in the magnification of the image and rotation of the image are corrected.

Abstract: A scanning electron microscope comprises: an electron gun for emitting an electron beam; a system of condenser lenses; scanning coils; and an objective lens having inner and outer magnetic polepieces to form a magnetic field lens below the lower ends of the polepieces. The inner and outer polepieces are provided with mutually communicating bores via which the backscattered electron detector can be withdrawably inserted into the electron beam path within the objective lens.