Improved understanding of electron density and temperature in a low pressure VHF-CCP from kinetic simulation

Summary form only given. Low pressure capacitively coupled plasma discharges are a promising plasma for biomedical applications. However, in recent experiments using a hydrogen gas, electron densities and temperatures from two measurements (multipole resonance probe and optical emission spectroscopy) disagree. Possible explanations for this disagreement include negative ion formation and non-thermal velocity distributions. We use kinetic plasma modeling to help understand this disagreement. In particular we show the effect of the rate of negative ion formation on the overall plasma density, and we estimate the effect of non-thermal electrons on the temperature diagnostics.