Heating and melting of plasma-born hydrogenated silicon clusters by reactions with atomic hydrogen



Ab initio molecular dynamics simulations have been carried out to investigate quantitatively “realistic” heating and melting processes of plasma-born hydrogenated silicon clusters due to reactions with atomic hydrogen in a plasma reactor. For H-exposure processes, we have chosen one hydrogenated amorphous silicon cluster (Si15H10) and the 1 nm hydrogenated silicon nanocrystal Si29H24. Our results indicate that the average energy resulting from each H-atom reaction is about the same for both the amorphous and the initially crystalline clusters before the clusters start undergoing their structural transition from the solid to the liquid state. We show that the melting temperature of the Si29H24 nanocrystal is between 1621 and 1668 K and that its complete phase transition takes about 15 ps after the melting temperature is reached.