Investigation on electron bounce resonance heating at various chamber heights in a low pressure inductively coupled plasma

Abstract

In this thesis, the electron bounce resonance is studied in a low pressure planar inductively coupled plasma (ICP) in a nonlocal regime. In this regime the collisionless electron heating plays an important role, significantly influencing the distribution of electron energy. The electron energy probability functions (EEPFs) are measured at different chamber heights and energy diffusion coefficients are calculated by the Fokker-Plank equation. It is found that EEPFs begin to flatten at the first electron bounce resonance condition and this plateau shifts to a higher electron energy as the chamber height increases. It indicates that strong electron heating occurs at the energy of the plateau. Each energy region of plateau corresponds not only to bounce resonance conditions but also to peaks of the first component of energy diffusion coefficients. These results show that the plateau formation on the EEPFs is mainly due to electron bounce resonance by interaction of electron bouncing motion between the reactor walls and external radio frequency (rf) electric field.