Modelling of magnetic field profile effects in a helicon source

The effect of altering the dc magnetic field on plasma properties and wave characteristics in a helicon source is studied. A two-dimensional, numerical model with self-consistency between wave propagation, including the Trivelpiece–Gould mode, and plasma transport is used. A parametric study is carried out to ascertain the magnetic field profile effects on wave propagation, peripheral versus bulk power absorption, plasma density, uniformity, temperature and potential. It is found that diffusion of plasma and power absorption away from the radio frequency antenna can be enhanced by adjusting the magnetic field profile. The effect on plasma uniformity qualitatively agrees with the measured data in the literature.