This master’s thesis investigates the interactions between neutral reactive hydrogen atoms and a tin surface in a radio-frequency (RF)- coupled hydrogen plasma, focusing particularly on the formation of the stannane molecule (SnH$_4$). In the plasma's afterglow region, where the measured density of neutral hydrogen atoms is of the order of $n\approx 10^{21} \ \rm m^{-3}$, the etching rate of tin by hydrogen atoms was determined using secondary ion mass spectrometry (SIMS) depth profiling and found to be $w=0,8 \ \rm \frac{nm}{s}\ (1\pm12\ \%)$. From this, the number of hydrogen atoms required to remove a single tin atom was calculated as $Y^{-1}=28800 \ (1\pm8\ \%)$. Additionally, the formation of tin droplets on the silicon surface was analysed. These droplets result from localised heating caused by the deposition of dissociation energy from the hydrogen molecule. Understanding these interactions is relevant for the development of liquid metal divertors in tokamak fusion reactors and for advanced plasma-based technologies such as extreme ultraviolet (EUV) lithography.
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