13 . n. The energy influx from an rf plasma to a substrate during plasma processing. W.W. Stoffels, E. Stoffels, H. Kersten*, M. Otte*, C. Csambal* and H. Deutsch Department of Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven
The energy influx from an rf plasma to a substrate during plasma processing
W.W. Stoffels, E. Stoffels,
H. Kersten*, M. Otte*, C. Csambal* and H. Deutsch
Department of Physics, Eindhoven University of Technology,
PO Box 513, 5600 MB Eindhoven
* Institute for Physics, University of Greifswald,
Domstr. 10a, D-17487 Greifswald, Germany.
The work has been supported by the Royal Dutch Academy of Sciences (KNAW) and the Deutsche Forschungsgemeinschaft (DFG) under SFB198/A14.
The ion and electron heating depends on surface potential: =>Separation of neutral component possible by using a bias voltage
Cs: heat capacity substrate; ji,je ion/electron flux; Vpl -Vfl acceleration voltage of ions in sheath
The probe is a Cu plate, diameter 3.4 cm, height 0.002 cm. Mounted to a thermocouple and shielded from below (see picture). It can be moved (x,y,z) and rotated.
Photograph of the thermal probe placed in the glow at substrate position.
TS(t)-curves as measured during the argon plasma process (p=1Pa, P=15W) for three substrate voltages (0, -46, -95V).
Rising edge plasma on, decreasing edge plasma off. The plasma heat flux is determined from the derivative signal
Current-voltage characteristic of the thermal probe for argon and oxygen.
The measured electron and ion flux is used to separate ion and electron heating from neutral heating.
ne = 2 1015 m-3
Calculated contributions by ions (Ji, Jrec) and electrons (Je) to the thermal balance of the substrate. The calculations are based on ne measured by the Langmuir probe and a Bohm flux. For the electron current (right branch) the measured substrate current is used.
Measured data fitted by the model results.
Measured integral energy influx (Qin) for argon and oxygen, respectively, for the same macroscopic discharge conditions.
Comparison with argon