To address this issue erosion of molybdenum (Mo) thin films on graphite substrate by deuterium (D) ions was investigated. Such composition of samples was chosen on the basis that same studies ants to be carried out in ASDEX Upgrade. For this purpose we constructed an experimental setup where samples are exposed to D ions generated by an electron cyclotron resonance ion gun. The dominating ion species coming out from the ion gun are D3+ ions, which are accelerated by applying 3.1 kV voltage in this case and decelerated in front of the sample to 3.0 keV, therefore yielding 1 keV energy per D.
120 nm thick Mo films deposited by pulsed laser deposition on graphite substrate of different roughness were produced for this purpose. The surfaces roughness (Ra) ranged from mirror polished surfaces (Ra= 5 nm) to rough surface (Ra= 2-3 µm). Samples were exposed to 1.5×1023 D ions/m2 at different impact angles with respect to the surface (0°, 40°, 60° and 70°). The erosion was determined by measuring Mo areal density before and after the exposure by Rutherford Backscattering Spectroscopy (RBS). The RBS measurements were performed by 2.5 MeV 4He ion beam. In the presented contribution results of the effect of surface roughness on sputter yields and its angular dependence will be discussed in details as we observed clear angular dependence for Ra~5 nm which is smeared out at higher surfaces roughness.
|Publication status||Published - 2019|
|MoE publication type||Not Eligible|
|Event||28th International Conference Nuclear Energy for New Europe, NENE 2019 - Grand Hotel Bernardin, Portorož, Slovenia|
Duration: 9 Sept 2019 → 12 Sept 2019
Conference number: 28
|Conference||28th International Conference Nuclear Energy for New Europe, NENE 2019|
|Abbreviated title||NENE 2019|
|Period||9/09/19 → 12/09/19|