| 摘要 |
PURPOSE:To measure incidence energy easily and accurately by detecting the time difference between the output signal of a modulation means and that of a density detection means and the ion speed and energy depending upon the detected time difference. CONSTITUTION:A deflected ion beam passes through an ion density detection section 22 and is injected into a semiconductor substrate 17. The density detection section 22 detects the change of ion density immediately before the semiconductor substrate 17 and this detection signal is sent to a time difference measurement circuit 23. Besides, the modulation signal is sent from a modulation section 18 to the time difference measurement circuit 23 and the time difference between this detection signal and modulation signal is measured. As a result, by pre-establishing a relationship among time difference, acceleration speed, and ion energy, the ion energy can easily be calculated. |
