Plasma cleaning enhancement via static magnetic field in transformer-coupled plasma reactors

Transformer-Coupled Plasma (TCP) sources are widely used in plasma etching due to their ability to generate uniform, high-density plasmas under low-pressure conditions. However, byproduct accumulation on chamber walls during repeated processing degrades plasma stability and increases cleaning frequency and duration, reducing throughput. Despite its extremely high Global Warming Potential (GWP) of 17,200, NF₃ remains the industry standard, while low-GWP alternatives still suffer from limited cleaning efficiency.

In this work, we propose a magnetic field-assisted approach to improve the cleaning performance of low-GWP gases in TCP chambers. Magnetic modulation of charged particle dynamics enhances wall-directed ion kinetic energy flux and optimizes ion incidence angles—two key factors in surface removal. Fluid plasma simulations were performed over various magnetic field intensities and spatial profiles to identify optimal conditions. A Maxwell coil setup on chamber sidewalls was modeled to validate field shaping and real-time control.

Simulation results show that the proposed configuration increases ion flux and induces favorable incidence angles at the chamber wall, enhancing contamination removal. This work demonstrates that magnetic field-based control can significantly improve the cleaning efficiency of environmentally friendly gases without major hardware modifications, offering a sustainable plasma processing strategy.