Measurement of pre-sheath potentials inradio-frequency discharges

Abstract EN

In radio-frequency (RF) discharge the sheath potential is defined as the difference between the plasma potential and the direct-current (DC) bias voltage, Vsheath = Vp-Vdc-bias.

It is found that sheath potential is a constant potential.

In radio-frequency discharge the plasma was produced by a 13.56 Mhz radio-frequency wave.

The energy of this wave is the steady voltage known as root-mean-square voltage multiplied by the elementary charge e.

That is, the energy of the wave is given by eVrms.

It is found that the energy of the secondary electron is almost equal to the energy of radio-frequency wave, Es = eVsheath = eVrms.

This led to the establishment of the driven electrode basic principle, which states that : “In RF discharge, electrons emitted from the driven electrode biased below the plasma potential during the RF cycle are lost to the plasma while electrons emitted from the driven electrode biased above the plasma potential during the RF cycle are reflected back to the driven electrode, if space charge effects can be ignored”.