plasma characterization

The Thin Film Laboratory of the OUT e.V. offers a compact combined multifunctional plasma and deposition sensor for characterizing plasma-, deposition and etching processes.
The sensor combines three measurement principles at the same measurement spot. Total energy influx, the growth rate and the plasma parameters (Langmuir probe) can be determined.
  • Measurement of the total energy influx:
  • based on the radiometer principle of Gardon
  • measurement of thermal radiation from the backside of the sensor
  • external calibration of the absolute energy influx Etot with an energy (radiation) source or internal calibration using the electrons of the process plasma
  • Energy flux range: about 1 mW/cm2 to 1 W/cm2
  • Front electrode potential adjustable in the range from -100 V to +50 V (adjustable ion/ electron current to surface)

  • Quartz crystal microbalance (QCM)
  • measuring of the frequency change of a crystal
  • Determination of deposition rate R and current film thickness d
  • Useable for thin film deposition and film etching
  • Usage of commercial quartz crystals (ø14 mm, f0 = 6 MHz)

  • Planar Langmuir probe:
  • Measurement of the voltage-current characteristics at the front electrode of the quartz crystal (voltage range -100 V to +50 V, max. current 100 mA)
  • Determination of the plasma parameters floating- Vfloat and plasma potential Vplasma, electron temperature Te together with electron ne and ion density ni using a LabView based analysis software
  • In combination with film rate R measurement calculation of the energy influx per film-forming particle Pein / Jneutral and the ion-to-neutral particle ratio jIon / jneutral
  • Current measurement at static potential