| 摘要 |
PURPOSE:To greatly improve the ionization efficiency and the ionic specificity of an ion beam generator by resonantly exciting the ionization substance to an autoionization state immediately before ionizing the substance. CONSTITUTION:Boron vapor 10 is introduced into a case 1 through a gas introduction hole 1a and voltage is applied across electrodes 5 and 6. As the result, electrons produced by glow electric discharge or gas electric discharge strike the boron vapor 10 to resonantly excite it to a metastable state. Synchronously with the above voltage application, light (B4) radiated by a synchrotron is introduced into the case 1 through a slit 1c to resonantly excite the boron vapor 10 to an autoionization state and then ionized with a given transition probability. D.C. voltage is applied across the electrode 6 and a sample base 8a and the ionized boron vapor 10 is irradiated upon a sample 8 as an ion beam 9 consisting of boron ions alone. |
