Recent Progress on Non-Uniform Magnetic Field Helicon Plasma

Helicon plasma has the characteristics of high ionization rate, low working pressure, low external magnetic field, no internal electrode and good static uniformity. It is widely used in fusion research, plasma propulsion, plasma material processing and other fields. The coupling efficiency of helicon plasma with a non-uniform magnetic field is different from a uniform magnetic field. The application of a non-uniform magnetic field in the helicon plasma source can significantly improve plasma parameters and RF energy absorption and improve plasma ionization efficiency. In this paper, the design and distribution of magnetic field, discharge characteristics and applications of helicon plasma with a non-uniform magnetic field are reviewed, and the development direction of helicon plasma with a non-uniform magnetic field is proposed.