| 摘要 |
PURPOSE: To manufacture a pure Al ion current for Al ion implantation useful for the microelectronics industry. CONSTITUTION: An electrode 8 is input, an electron flow is formed in a chamber 7, and the flow is accelerated by a wall 6 having positive potential against an electrode 8. SiF4 is introduced in the chamber 7 through a duct 12, ionized, then plasma is formed. The plasma is rebounded by a negative plate 9, and is confined to the center area of the chamber. This plasma has an extremely high temperature, and Al feed material Al2 O3 is divided, and releases a kind of Al ions which unite with the plasma. Al<+> of equivalent weight (weight/charge) 27 is only ion which exists in the plasma to be isolated from the other ions. Thus, the intensity of a magnetic field in a selective passage 20 needs only to be adjusted so that the ions having equivalent weight 27 are extracted from a window 22. |
