The effect of external cusp magnetic field on Ar ICP characteristics

In this paper, three permanent magnet rings, which were placed alternatively between the three antenna coils of a cylindrical inductively coupled radio frequency (rf) argon plasma for rf enhanced ionized magnetron sputtering system, were used to produce a closed magnetic field distribution with the magnetic field of the unbalanced magnetron sputtering to confine discharge plasma. Langmuir probe measurement was used to study the effect of the magnetic field on the plasma characteristics and their spatial distribution. The results show that the presence of the closed magnetic field leads to the increase of the ion density and the decrease of electron temperature and plasma potential. With the closed magnetic field, the plasma density distribution in radial direction will become more uniform.