To provide an ion source capable of adjusting average value of a radial-direction distribution of ion-beam intensity while maintaining uniformity of the radial-direction distribution of the ion-beam intensity.
The ion source 14 is provided with a discharge vessel 30 on which an opening 30a is formed; a coil 32 fitted outside the discharge vessel 30 for generating plasma 33 inside the discharge vessel 30; a drawing-out electrode 35 drawing out ion in the plasma 33 generated inside the discharge vessel 30 and generating ion beams 26; a power supply device 42 supplying power to the coil 32; and a control device 44 capable of repeatedly stopping an output power P for a given period, while maintaining a value of the output power P output from the power supply device 42 at a predetermined value P0 uniformizing a radial-direction distribution of ion-beam intensity of the ion beam 26.
HOTTA AKIHIRO
Shiro Terasaki
Hiroaki Aoki