Zinc sulfide continues to generate interest due to the fact that compared to other semiconductors it has a large direct band gap, making it desirable in optical applications. In these applications only high quality zinc sulfide films can be employed. The default approach for producing zinc sulfide films are through chemical vapor deposition (CVD). However, there is a large potential for defects in the deposited film primarily due to the fact that the morphology of adducts are different in the gas phase compared to that in the solid phase (i.e. deposited film). The impact of adducts depend on the size distribution of clusters, which create large distorted grains on the substrate that do not normally have the same morphology as the deposited film. Basically the main issue is how big these clusters grow; larger clusters make it more likely to have defects in the deposited film.<br/><br/>In our previous research we employed a computational approach to predict the size distribution and morphology of the clusters. With this information we were able to explain the link between the cluster size and the morphological defects on the deposited film. In our approach we coupled the macro-scale computational fluid dynamics with molecular scale molecular dynamics and nano-scale ab-initio calculations in order to estimated the nucleation, growth, dynamics, and size distribution of the particles inside the CVD reactor. This presentation shows advances we have made using new modeling modalities; specifically we will discuss a Multi-Agent Approach for coupling molecular modeling, specifically molecular dynamics in which the force fields are periodically updated with DFT calculations with macro level (i.e. continuum based) computational fluid dynamics and/or general particle dynamics. In summary our approach uses a multi-agent approach to bridge the time and space scales of molecular level calculations and continuum scale modeling.

Multi-agent approach for molecular modeling in chemical vapor deposition

251st National Meeting (2016)

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