ION COLLECTION BY A HOLLOW PROBE IN ECR MICROWAVE PLASMA UNDER A DIVERGENT MAGNETIC-FIELD

Ion collection by a hollow probe has been studied in electron cyclotro n resonance (ECR) microwave plasma under a divergent magnetic field wh ere an ion beam was accelerated along the plasma axis, The ion current collected by the probe was found to consist of currents proportional to the geometric solid angle from the probe collector caused by the io n beam parallel to the probe axis. The effect of the ion beam energy a nd its injection angle to the probe has been also discussed.