| 摘要 |
PURPOSE:To substantially remove contamination of the objective visual field of a sample to be observed without using high vacuum and obtain a high resolution scanning image by irradiating an electron beam on the objective visual field through the operation of a visual field shifting circuit. CONSTITUTION:The electron beam 1 which is emitted from an electron gun 5 is converged on a sample 2. The secondary electron signals 9 which are generated from the surface of the sample 2 are detected 10, amplified 11, and displayed on the screen of a CRT13 as an image. The electron beam 1 which irradiates the surface of the sample 2 is scanned two-dimensionally. This scanning sends the electrical signal which is driven by a deflection power supply 16 to a deflector 7, through a magnification converter 19 and thus deflects electron beam. Since the deflection power supply 16 synchronizes with the deflector 7 and drives the deflector 14 of the CRT13, the secondary electron signals 9 which synchronize with the electron beam on the sample 2 are displayed on the CRT13. When the magnification converter 19 and the visual field shifting circuit 20 are at operating status, the electron beam 1 is irradiated at the visual field near-by which is not overlapped with the objective visual field and magnification is also improved. |
