| 摘要 |
Charged-particle-beam (CPB) mapping projection-optical systems and adjustment methods for such systems are disclosed that can be performed quickly and accurately. In a typical system, an irradiation beam is emitted from a source, passes through an irradiation-optical system, and enters a Wien filter ("ExB"). Upon passing through the ExB, the irradiation beam passes through an objective-optical system and is incident on an object surface. Such impingement generates an observation beam that returns through the objective-optical system and the ExB in a different direction to a detector via an imaging-optical system. An adjustment-beam source emits an adjustment beam used for adjusting and aligning the position of, e.g., the object surface and/or the Wien's condition of the ExB. The adjustment beam can be off-axis relative to the objective-optical system. For such adjusting and aligning, fiducial marks (situated, e.g., in the plane of the object surface) can be used that are optimized for the CPB-optical system and the off-axis optical system. Desirably, the image formed on the detector when electrical voltage and current are not applied to the ExB is in the same position as the image formed on the detector when electrical voltage and current are applied to the ExB. Also provided are "evaluation charts" for use in such alignments that do not require adjustment of the optical axis of the irradiation-optical system, and from which the kinetic-energy distribution of the emitted adjustment beam is stable.
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