| 摘要 |
PURPOSE:To constitute a lens using ion beams and electron beams in common by arranging electrodes above and down an iris of a magnetic lens consisting of a coil winding and a magnetic pole and impressing high voltage on the iris in order to form an electrostatic lens. CONSTITUTION:A magnetic lens is formed by a coil winding 1 and a magnetic circuit 2 while electrodes 3 and 5 for an electrostatic lens having earth potential are arranged above and below the iris 4 thereof and high voltage is impressed by way of the iris as an intermediate electrode in order to form the electrostatic lens while composing devices using ion-and-electron beams such as an ion beam exposure device, an analytical device or the like using an ion source. Accordingly, by providing the iris with plural hole diameters, some of which suit in case of the magnetic lens while the rest suit in case of the electrostatic lens, and using them selectively, the iris can be used in common for the electrostatic lens when focusing ion beams and for the magnetic lens when focusing electron beams. |
