Hysteresis and mode transition in terms of electron energy distribution function for an inductively coupled argon discharge

The electron energy distribution function (EEDF) with respect to the hysteresis loop of an inductively coupled argon discharge has been studied experimentally. Contrary to H mode, knowledge of EEDF in E mode is still limited, and an elaborate EEDF measurement with regard to power and pressure for this mode is presented. The Langmuir probe measurements reveal two regions with distinct EEDFs in E mode, which might be a critical missing factor in explaining the unresolved hysteresis and mode transition phenomenon of inductive discharges. Furthermore, a Poynting vector representation has been used to explain the power coupling in an inductive discharge, where (azimuthal) eθ component is proposed to be dominant in the “hybrid mode” region.