Numerical study of the effects of discharge parameters on capacitively coupled plasma in a magnetic field

Abstract

The impact of electrode spacing, power supply voltage, radio frequency, and gas pressure on capacitively coupled plasma discharge under both weak and strong magnetic fields is investigated by using a one-dimensional implicit particle-in-cell/Monte Carlo collision simulation. Simulation results indicate that under both weak and strong magnetic field conditions, plasma density increases with the increase in these discharge parameters. However, the principle of density increase under weak and strong magnetic field conditions is slightly different. The strong magnetic field plays a crucial role in strongly constraining electrons. Under weak magnetic field conditions, the mutual transition between stochastic heating and ohmic heating can be observed, while under strong magnetic field conditions, ohmic heating predominantly prevails. Furthermore, the simulation results also indicate that a strong magnetic field can effectively reduce the voltage threshold for the transition from the α mode to the γ mode. The strong magnetic field strongly confines secondary electrons near the sheath, allowing them to interact multiple times with the sheath and acquire higher energy, thereby making the γ mode more likely to occur.