Thermal stability of silicon nanowires: atomistic simulation study

Using the Stillinger--Weber (SW) potential model, we investigate thethermal stability of pristine silicon nanowires based on classicalmolecular dynamics (MD) simulations. We explore the structuralevolutions and the Lindemann indices of silicon nanowires atdifferent temperatures in order to unveil atomic-level meltingbehaviour of silicon nanowires. The simulation results show thatsilicon nanowires with surface reconstructions have higher thermalstability than those without surface reconstructions, and thatsilicon nanowires with perpendicular dimmer rows on the two (100)surfaces have somewhat higher thermal stability than nanowires withparallel dimmer rows on the two (100) surfaces. Furthermore, themelting temperature of silicon nanowires increases as their diameterincreases and reaches a saturation value close to the meltingtemperature of bulk silicon. The value of the Lindemann index formelting silicon nanowires is 0.037.