PURPOSE: To provide high efficiency and eliminate problem of negative charging by projecting primary electrons aslant to the surface of a target for primary electron irradiation, locating an object to be ion implanted in the neighborhood in normal direction of the target surface, and furnishing an absorptive sink for reflected primary electrons on the side opposite the primary electron incident direction about the normal direction as the center.
CONSTITUTION: Secondary electrons emitted from the surface of a target 21 for primary electron irradiation have a flux peak in the normal direction to the target surface, and in the neighborhood in this direction a desk 23 for fitting of the object to be ion implanted is arranged, so that a major portion of the secondary electrons can reach it, which should give a good secondary electron supply efficiency. An absorptive sink 27 for reflected electron beam is installed in the direction where the flux of reflex primary electron component presents a peak, and the reflex electron component nullifies there, so that no high energy electrons will reach the object to be implanted. Thereby there is no fear of occurrence of dielectric breakdown or deterioration of characteristics because of negative charging.
MATSUDA SHINTARO
YAMAMOTO HIROHISA
