| 摘要 |
PURPOSE:To prevent the deflection caused by the off-centering of an electron beam when operating correction lenses by installing a stigmatic correction lens or an astigmatic correction lens at the position of a deflector or in the magnetic field of an objective lens above it. CONSTITUTION:An objective lens in an electron beam device is formed with a magnetic field 17 and an electromagnetic coil 18, which generate magnetic fields with opposite magnetism each other. A deflector 18 made with a deflection coil is installed in the upper magnetic field of an objective lens, a stigmatic correction lens 20 is installed in the magnetic field of an objective lens above the deflector 19, and furthermore, an astigmatic correction lens 21 is installed at the position of the deflector 19 respectively. An electron beam 22 is shifted on a sample surface 23 by the deflector 19, and the stigmatic correction lens 20 and astigmatic correction lens 21 are operated in response to the deflection position. Accordingly, the correction lens 20 is operated before the electron beam is deflected, thus deflection characteristics are not affected and causes of the deflection distortion can be eliminated. |
