Journal of Nanomedicine & Nanotechnology

Multiscale modeling of the atomic layer deposition of HfO2 thin film grown on silicon: How to deal with a kinetic monte carlo approach

3^rd International Conference on Nanotek & Expo

December 02-04, 2013 Hampton Inn Tropicana, Las Vegas, NV, USA

Ahmed Dkhissi

Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

In this presentation we discuss briefly the principles of the multiscale modeling and its applications in nanomaterials and nanoscience through selected applications. Indeed, to investigate the atomic layer deposition (ALD) of HfO 2 on Si(100) surface, an original integrated approach developed within a multiscale strategy, which combines first-principles quantum simulations and kinetic Monte Carlo (KMC), is presented. Density functional theory within the hybrid functional is used to determine the detailed physicochemical mechanisms and associated energetics of the two half cycles taking place during the initial stage of film growth. A kinetic Monte Carlo model is then proposed that deals with the stochastic nature of the calculated DFT mechanisms and barriers. Beyond the chemical information emanating from DFT calculations, the lattice-based KMC approach requires preliminary physical considerations issued from the crystal structures that the system is intended to adopt. This is especially critical in the case of heterogeneous systems like oxides deposited on silicon. We also describe (i) how atomistic configuration changes are performed as a result of local events consisting in elementary reaction mechanisms occurring on specific lattice sites, (ii) the temporal dynamics, governed by transition probabilities, calculated for every event from DFT activation barriers, and (iii) the relation of KMC with the ALD experimental procedure. Some preliminary validation results of the whole multiscale strategy are given for illustration and pertinence with regard of the technological main issues.

Biography :

Ahmed Dkhissi received a Ph.D. in Physics from the University of Paris XI in 1996. After postdoctoral studies at the University of Leuven and the University of Mons, he became a senior researcher. The main activity of his research is focused on multiscale modeling and simulation of nanomaterials and biological systems. Modeling methods include atomistic, quantum simulations, kinetic MonteCarlo, statistical mechanics and macroscopic simulations. Structure-property relationships of Molecules, biomolecules, nanoparticles, ?-conjugated materials and nanoscale interfaces are the main focus of modeling research. He is (co)author of over 55 papers in international peer-reviewed journals and more 1000 citations. He is member of Editorial board of ISRN Physical and Chemistry, and International Journal of Renewable and Sustainable Energy (IJRS