A simple analytic model valid for all collisionality regimes is developed to describe the power deposition in a cylindrical inductively coupled plasma source with a planar coil. The heating is ohmic at high pressures and remains finite at low pressures. The low-pressure collisionless heating is due to kinetic nonlocal effects. The model is in good agreement with other calculations of collisionless heating. A diffusion model is then used to determine the plasma density profile and the electron temperature in terms of the gas pressure and the source geometry. The heating and diffusion models are used to determine the scaling of the inductive electric field with applied frequency and input power, and the results are compared with published experimental data to verify the scaling.

Particle-in-cell Monte Carlo simulation has become a very effective tool in exploring processing plasmas and in particular capacitive RF discharges. We describe the conventional particle-in-cell (PIC) simulation and its limitations in terms of computational efficiency, review the implicit subcycling methods used to improve computational efficiency for many problems, and analyse conventional and implicit subcycling PIC simulation performances on an RF discharge model. Implementation of the implicit subcycling scheme in our bounded one-dimensional electrostatic code, PDPI, resulted in an order of magnitude reduction in the simulation run time when the accuracy conditions were satisfied.

Weakly ionized processing plasmas are studied in two dimensions using a bounded particle-in-cell (PIC) simulation code with a Monte Carlo collision (MCC) package. The MCC package models the collisions between charged and neutral particles, which are needed to obtain a self-sustained plasma and the proper electron and ion energy loss mechanisms. A two-dimensional capacitive radio-frequency (rf) discharge is investigated in detail. Simple frequency scaling laws for predicting the behavior of some plasma parameters are derived and then compared with simulation results, finding good agreements. It is found that as the drive frequency increases, the sheath width decreases, and the bulk plasma becomes more uniform, leading to a reduction of the ion angular spread at the target and an improvement of ion dose uniformity at the driven electrode.

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Bi-Maxwellian electron energy distribution functions (EEOFS) have been measured experimentally in argon RF discharges at 13.56 MHz by Godyak et a/ (Plasma Sources Sci. Techno/. 1 36 (1992)). The observed EEDFS at low pressures had very-low-energy and high-energy components. We show particle-incell Montecarlo (PICMCC) simulations, which produce the same EEDFS. Excellent agreement is obtained between the effective low and high electron temperatures in simulations and those measured in the laboratory. Our simulations, with the Same physical parameters as in the laboratory, obtain the same transition point in the electron heating mode, from stochastically dominated heating at low pressures to ohmically dominated heating at high pressures.