| Summary: | Nanotechnology has, without a doubt, ushered in a new era of technological
convergence and holds the promise of making a profound impact on the way
research in physics, chemistry, materials science, biotechnology etc. are
conducted. The novel properties of materials at the nanoscale (or nanostructures)
make them useful in a variety of applications, from catalysis to the medical field
and electronics industry. However, to exploit these properties at the nanoscale,
precise control over the morphology and size of nanostructures is required. One
strategy that may be explored to tailor nanostructure morphology and size is
vapour deposition. A lot of further insight can be gained from computer
simulations of the processes governing the growth of nanostructures during
vapour deposition. A method that shows promise in simulating thin film growth
through vapour deposition is kinetic Monte Carlo (KMC). Therefore, in this
study, a KMC model was developed to describe growth through vapour
deposition. A gold on graphite system was simulated to test the model. In this
KMC model, substantial effort was devoted to developing the model in different
stages, each stage being more robust than the previous one. The assumptions
made at each stage and possible artefacts (unphysical consequences) arising from
them are discussed in order to distinguish real physical effects from artificial
ones. In the model, data structures, search algorithms and a random number
generator were developed and employed in an object-orientated code to simulate
the growth. Several simulations were performed at different growth conditions
for each of the stages. The results are interpreted based on the kinetic constraints
imposed during the growth.
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