Multicusp Type Electron Cyclotron Resonance Ion Source for Plasma Processing

Abstract

A multi-cusp type ECR (electron cyclotron resonance) ion source is built with use of SmCo magnets and 2.45 GHz-TE 11 circular mode microwave. The ion source is operated at pressures from 10 -4 to 10 -3 Torr with the input microwave power from 100 to 400 W. In hydrogen, the current density of H + is higher than those of H 2 + and H 3 + . The dependence of the fraction of each ion species on the power and pressure is measured and explained by rate equations. The source is operated also in other gases. Mass spectra in He, N 2 , O 2 , Ar and CH 4 are shown together with the pressure and power dependences. Multicharged state of up to 3 has been obtained.