| 摘要 |
PROBLEM TO BE SOLVED: To carry out axis alignment so as an optical axis of an electron beam to pass through centers of a condenser lens and an objective lens, respectively, in case of structuring a covergent lens using condenser lenses in two stages with relative positions fixed. SOLUTION: An inlet side beam deflection part 2 is arranged between the convergent lenses 31, 32 in two stages whose focuses each can be adjusted, and an electron gun 1; and an outlet side beam deflection part 4 is arranged between the convergent lenses 31, 32, and an objective aperture plate 5. Each of the beam deflection parts 2, 4 consists of deflectors in two stages arranged in an axis C direction, respectively. Even in case the centers of the convergent lenses 31, 32 are not on the axis C, an optical axis can be aligned to the center of the both convergent lenses 31, 32 by deflecting beams in two stages with the inlet side beam deflection portion 2, and further, the optical axis can be aligned to the center of the objective lens 7 by deflecting the beams in two stages with the outlet side beam deflection part 4. COPYRIGHT: (C)2011,JPO&INPIT
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