Two-dimensional particle-in-cell simulation to investigate electron heating mechanism in intermediate-pressure RF hollow cathode discharges

Abstract While electron heating in a low-pressure DC hollow discharge occurs by the electron pendulum effect in the hole, the heating mechanism of RF hollow discharges at high collisionality is not fully elucidated yet. Phase-resolved analysis with a two-dimensional particle-in-cell simulation enables the investigation of how the electron heating and density distribution changes by the electrode shape, bias voltage, secondary electron emission (SEE), and gas pressure in the RF hollow cathode discharge. As gas pressure increases, the plasma enters the hole with a reduced energy relaxation mean free path, and two density peaks appear inside and outside the hole. Electron heating at various locations is analyzed for DC bias and SEE variation.