Fundamentals of Electron Dynamics in Low Pressure Capacitively Coupled Radio Frequency Discharges

Capacitively coupled radio frequency (CCRF) discharges are indispensable tools for the semiconductor and coating technologies. At low pressures (
$\mathrm{p} < 10\ \text{Pa}$
), the discharge operates in a very ‘nonlocal’ regime. Electrons interact with the space- and time dependent electric field and traverse a certain distance (electron mean free path) collisionlessly. Consequently, the local electron velocity distribution function becomes anisotropic and the discharge exhibits complex electron dynamics, such as nonlinear effects and resonance phenomena. In the last 50 years, various terminologies have been introduced which are based on theoretical, experimental and computational work in order to study the electron power absorption at low pressure, e.g., stochastic heating, nonlinear electron resonance heating, pressure heating, ambipolar heating, wave-particle-heating and many more. It is not the aim to give an overview of all these previous approaches, but to introduce a basic strategy for the analysis of the dynamics of electrons for a universal electropositive CCRF discharge scenario (3 Pa, argon).