The current model has proven to have a robust ability in simulating RF sheaths including erosion rates and detailed sputtering physical features but the validation of the model is required to establish a trust in its simulation capabilities. Due to the dependence of the erosion rate on several parameters that are regularly unreported in literature such as mag- netic field angle ψ, a dedicated collaboration on an active erosion experiment would ease the process of experimental data acquisition.
The best path forward to such a collaboration would be performing the experiment on a linear plasma device using a single strap antenna as a RF wave source. The use of a linear plasma device guarantees more control on the creation of far-field sheaths by placing an erosion target downstream on the opposite end of the electrically biased RF antenna. The use of a single strap antenna allows us to study large edge interactions without the need for large RF power levels. Single strap antennas are also easier to set up and rotate for changes in alignment. This allows us to study the effects of magnetic field misalignment on the erosion rate and sheath rectification physics. Validation data needed would not require specialized equipment as a simple measurement of the eroded thickness of the erosion target and the total RF operation time would be sufficient for the calculation of the erosion rate. The erosion rate is a quantity that can be simulated given the known operating conditions and hence easily verified with experimental data.
In addition to establishing trust in the models capabilities the following improvements can be made to enhance the usage of the model:
• Addition of impurity self-sputtering capabilities that has been shown to be a major concern with Carbon FS material.
• Expansion of the F-Tridyn lookup table data base to include larger sets of relevant materials such as Ni, Ti, W, Mo.
• Further investigations into the observed backward ion flux seen under restricted con- ditions in chapter 3.
• Effect of ion induced mixing between the Be coating and the Copper layer in the RF antenna on the lifetime of the ICRF device.
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