Effect of magnetic field on capacitively coupled plasma modulated by electron beam injection

The magnetic field can effectively affect the properties of capacitively coupled plasma (CCP) modulated by electron beam injection, leading to improved discharge performance. In this study, a one-dimensional particle-in-cell/Monte Carlo collision model is used to simulate electron beam injected CCP under various magnetic fields. At a pressure of 20 mTorr, increasing the magnetic field from 0 to 50 G initially caused the plasma density to increase and then fall, with a peak density observed at 20 G. This is because the gyroradius of the injected electrons in the magnetic field is comparable to the electrode gap. When the pressure is increased, this effect is significantly weakened due to the disruption of the electrons’ gyration. Additionally, the electron energy distribution is significantly impacted by increasing the magnetic field. An increase in the magnetic field reduces the maximum ion energy and significantly enhances ion flux at the powered electrode. At the grounded electrode, when the maximum cyclotron radius of the injected electrons is comparable to the electrode spacing, the ion flux reaches its maximum. Further increasing the magnetic field results in a decrease in ion flux. This is crucial for semiconductor etching processes aiming to reduce electrode damage and improve etching efficiency. It also provides new insights for plasma research.