Pulse modulated microwave operation on large bore electron cyclotron resonance ion source with cylindrically comb-shaped magnetic fields configuration.

In order to enhance efficiency of an electron cyclotron resonance (ECR) plasma for broad and dense ion beam source under the low pressure, the magnetic field configuration is constructed by a pair of comb-shaped magnet which has opposite polarity each other, and which cylindrically surrounds the plasma chamber. By using the pulse microwave mode operation, we aim at generation of plasma with parameters that cannot be achieved at the continuous microwave (cw) mode. The maximum beam current is obtained in the experimental condition of the pulse width 100-200 micros at the duty ratio 40%-50%.

Production of electron cyclotron resonance plasma by using multifrequencies microwaves and active beam profile control on a large bore electron cyclotron resonance ion source with permanent magnets.

A new concept on magnetic field with all magnets on plasma production and confinement has been proposed to enhance efficiency of an electron cyclotron resonance (ECR) plasma for broad and dense ion beam source under the low pressure. The magnetic field configuration is constructed by a pair of magnets assembly, i.e.