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arXiv · 2011.10220

Simulation of 2D ballistic deposition of porous nanostructured thin-films

Abstract

A "two-dimensional ballistic deposition" (2D-BD) code has been developed to study the geometric effects in ballistic deposition of thin-film growth. Circular discs are used as depositing specie to understand the shadowing effects during the evolution of a thin-film. We carried out the 2D-BD simulations for the angles of deposition $20^0$-$80^0$ in steps of $10^0$. Standard deviations $1^0$, $2^0$, $4^0$, $6^0$ and $10^0$ are used for each angle of deposition with disc size of $1.5 \overset{\circ}{A}$ to understand its effect on the microstructure of the thin-films. Angle of growth, porosity and surface roughness properties have been studied for the afore-mentioned angles of deposition and their standard deviations. Ballistic deposition simulations with the discs of different sizes have been carried out to understand the effect of size in ballistic deposition. The results from this code are compared with the available theoretical and experimental results. The code is used to simulate a collimated glancing angle deposition (C-GLAD) experiment. We obtain a good qualitative match for various features of the deposits.

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S. Bukkuru, H. Hemani, S. M. Haque, J. Alphonsa, K. Divakar Rao, M. Warrier. 2020-11-20. Simulation of 2D ballistic deposition of porous nanostructured thin-films. https://arxiv.org/abs/2011.10220

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