| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a charged particle beam device which has a charged particle beam optical system to form an image of secondary charged particles with a wide energy range, and which is not affected by stray light when making observation with multi-beams. SOLUTION: The charged particle beam device is equipped a with a diaphragm 23 determined by an opening angle to pupil of a secondary optical system so that stray light 22 of an electron beam which does not contribute to an image formation may be cut. Namely, the aperture of a diaphragm 23 is formed as only an electron beam of which the secondary electrons have standard energy can reach directly on the focusing surface of a multi-detection unit 43. Accordingly, only the electron beams, which contribute to the image formation, is incident on the multi-detection unit 43, and the other electron beams, no contribution to the image formation, can not reach on the detecting surface of the multi-detection unit 43 because they are cut, and are reflected on the surface of a mirror cylinder 19. As a result, a superior observing image is obtained.</p> |
