Demands of the plasma processing industry gradually lead to an increase in electrode areas and driving frequency of the commonly used capacitively coupled reactors. This brings about new phenomena which differ from the well known physics of smaller capacitively coupled plasma (CCP) devices. In this work we compare experimental data and results of numerical modeling for a large CCP discharge having a GEC celllike geometry currently studied in context of a possible use as a sputtering device. Using an electrostatic implicit particlein cell code with MonteCarlo collisions (PIC/MCC), we have been capable of reproducing all main features of the experimental discharges, which have strong relevance for the processing applications, such as the plasma uniformity and the selfbias. The side chamber proves to play an essential role in defining the physics of the whole device, featuring substantial production of plasma particles and participating in establishing the selfbias due to the telegraph effect observed for higher frequencies.

The effect of a magnetic field on the characteristics of capacitively coupled radio frequency discharges is investigated and found to be substantial. A one-dimensional particle-in-cell simulation shows that geometrically symmetric discharges can be asymmetrized by applying a spatially inhomogeneous magnetic field. This effect is similar to the recently discovered electrical asymmetry effect. Both effects act independently, they can work in the same direction or compensate each other. Also the ion energy distribution functions at the electrodes are strongly affected by the magnetic field, although only indirectly. The field influences not the dynamics of the sheath itself but rather its operating conditions, i.e., the ion flux through it and voltage drop across it. To support this interpretation, the particle-in-cell results are compared with the outcome of the recently proposed ensemble-in-spacetime algorithm. Although that scheme resolves only the sheath and neglects magnetization, it is able to reproduce the ion energy distribution functions with very good accuracy, regardless of whether the discharge is magnetized or not.

A volume-averaged global model is developed to investigate surface-wave discharges inside either cylindrical or coaxial structures. The neutral and ion wall flux is self-consistently estimated based on a simplified analytical description both for electropositive and electronegative plasmas. The simulation results are compared with experimental data from various discharge setups of either argon or oxygen, measured or obtained from literature, for a continuous and a pulse-modulated power input. A good agreement is observed between the simulations and the measurements. The calculations show that the wall flux often substantially contributes to the net loss rates of the individual species.

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