Investigation of Step Growth on Nano Surfaces Depending on Temperature and Flux Rates Using the KMC Method
Abstract
In this study, the growth of nano-sized surface step structures was examined using the Kinetic Monte Carlo (KMC) simulation technique. The step growth and correlation function on the nano surfaces were analyzed at surface energy values of Eb = 100 meV, Ed = 80 meV, Eds = 150 meV, and Ek = 80 meV, where Eb is the bonding enegy, Eds is the step edge diffusion , Ed is the surface diffusion and Ek Schwoebel energy barrier values , with a surface flux of 1 atom every 10 ns directed towards the pre-formed stepped surfaces on the nano surfaces. The simulation temperature was set to T = 250 K. In this case, step growth was limited, but cluster structures played an important role in stepped surface growth. In a different scenario, at T = 300 K, the amplitude increased at a constant rate, and there were no step fluctuations. Surface growth increased, and the surface fluctuation amplitude also grew. At T = 350 K, when the temperature was raised further, step fluctuations has become dominant, the step fluctuation continued to increase at a constant rate, the step amplitude grew, and the number of islands decreased compared to the other two cases. In addition the correlation of steps is investigated for each temperature.
According to these results, the dynamics of step growth can be controlled by selecting an appropriate temperature and balancing the surface energy parameters.
Keywords
KMC method, Nano surfaces, Step growth, Surface diffusion energy, Temperature
Project Number
FBA-2024-16928
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