The goal of this master thesis was twofold. The first part was to validated the fixed Langmuir probe and to test the analyses method. Effect of scan speed, background vacuum, neutral gas and self-heating of the plasma on the IV curves were adressed. A recommendation on the test range and minimum datapoints were made. The second part was to look for the effect of secondary ionization electrons. The most probable hypothesis is that they originate from the target plate. however calculated density is small compared to the confinement electrons. A single Maxwellian distribution to the IV curve gave therefore already good results. However still a discrepancy of 10% was found which cannot be solved with a di-Maxwellian fit. Additional improvements on the model should be done as well as multi-component gases should be tackled.
|Place of Publication
|Published - Jan 2013