| 摘要 |
PURPOSE:To obtain an ion implantation device, which minimizes the loss of implantation beams easily, and enables corrective control of the drift of a sector- like magnetic field, by providing both a control circuit which can drive and control correction slits, and a correctivecontrol circuit which corrects the field intensity of the sector-like magnetic field. CONSTITUTION:In the figure, an ion beam 2 produced from an ion source 1 is deflected by a sector-like magnetic field (consisting of a field-producing coil) 3 which is controlled by a magnetic-field power source 4, and only desired kinds of ions reach a Faraday cup 9 after passing through the space between mass- separating slits 5 and 6. The proportion of coupling beams is regulated with control circuits 24 and 25 by combining correction slits 7' and 8' with driving mechanisms 10 and 11. The slits 7' and 8' trap ionic currents existing in the periphery of the beam 2. The drift of the deflected-beam axis is detected from the difference between the currents of the slits 7' and 8', and fed back to the magnetic-field power source 4. As a result, the field intensity of the sector- like magnetic field 3 is corrected. |
