| 摘要 |
A charged-particle beam instrument is offered which can cancel out deflection aberrations arising from a first deflector or oblique incidence on the surface of a workpiece without (i) increasing the electrode length, (ii) reducing the inside diameter of the electrode, or (iii) increasing the deflection voltage too much. The instrument has an electron source for producing an electron beam, a demagnifying lens for condensing the beam, an objective lens for focusing the condensed beam onto the surface of the workpiece, the first deflector located behind the demagnifying lens, and a second deflector located ahead of the demagnifying lens. The first deflector determines the beam position on the surface of the workpiece. The second deflector cancels out deflection aberrations arising from the first deflector.
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