Recrystallization of Amorphous Si in a Nanostructure

The uncomplete recrystallization can have several origins the effect of the oxide embedement, the small thickness of the crystalline seed after preamorphisation, the 

Once the atomic model is constructed, we performed a molecular dynamics simulation at finite temperature. We have chosen a temperature of 1700 K in order to have a SPE velocity similar to the experimental value at 1000 °C. The potential energy per atom versus time is presented in Fig. 6.11. The major decrease occurs in the interval [0 120ns]. Therefore we will study the structure at four moments of this interval 30 ns, 60 ns, 90 ns and 120 ns. 

For a purpose of clarity, we have chosen to restrict the representation to crystal-like atoms. We define for each atom i the parameter A  

The final structure is displayed in Fig. 6.17. All atoms are plotted in this view, including frozen and non-crystal like ones. Three regions can be delimited  

The final structure obtained by MD is therefore in agreement with the observation by TEM on the FinFET [4]. This agreement validates the approach of simulation as a reliable tool to study recrystallization in complex conditions that occur in nanostructures. 

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