Characterization of a microwave discharge by thermography

The slot antenna (SLAN) type microwave plasma source is characterized by use of thermography. The influence of microwave power (2.45 GHz, 600–1400 W), gas pressure (5–10 mbar) and oxygen flow (500–1500 sccm) on symmetry of the temperature profile along the axis of the cylindrical plasma chamber is investigated. The thermography results are compared with axial Langmuir probe measurements and with results of the electricfield simulations, for which the plasma is modelled by use of Drude model.