Enhancement of Harmonic Heating by Magnetized Plasma Series Resonance in Capacitive Radio Frequency Discharges

We present a novel resonance mode in capacitive radio frequency (rf) discharges in the presence of an oblique magnetic field at low pressures. We observe the self-excitation of high-frequency harmonics of the current in magnetized capacitive rf discharges through the magnetized plasma series resonance (MPSR) induced by applying a low-frequency power. Utilizing an equivalent circuit model, we reveal that these harmonics arise from the hybrid combination of the magnetic gyration of electrons and the PSR. When the MPSR occurs, the impedance of the series resonator system is at a minimum, resulting in the amplitude of higher harmonics being comparable to that of the fundamental frequency. The high-frequency harmonics with large amplitude cause strong oscillations in the electron heating rate, ultimately enhancing the total power dissipation. The presence of harmonics is suppressed by increasing the pressure due to collisional damping.