| AVS 54th International Symposium | |
| Thin Film | Tuesday Sessions |
| Session TF-TuA |
| Session: | Surface Chemistry for Atomic Layer Deposition |
| Presenter: | C.B. Musgrave, Stanford University |
| Authors: | C.B. Musgrave, Stanford University A. Mukhopadhyay, Stanford University J.F. Sanz, Universidad de Sevilla, Spain |
| Correspondent: | Click to Email |
We have used a combination of theoretical techniques to explore the surface chemistry of atomic layer deposition of metal oxides and nitrides, including HfO2, HfN, HfOxNy and WN. Our main focus has been on the chemical mechanisms involved in the ALD of HfO2. Density functional theory has been employed using both the cluster and periodic supercell models of the reacting surface to determine detailed mechanisms of the surface chemistry of ALD. In addition to locating transition states and applying transition state theory to predict reaction rates, we also simulate ALD surface reactions using Born-Oppenheimer quantum molecular dynamics. These simulations provide a rich and complex picture of the atomistic detail of the ALD process which shows that the chemistry of ALD is much more complicated than initial descriptions suggested. In addition to finding various reaction pathways and predicting their relative rates, we also investigate processes such as dissociation of adsorbed precursors via microsolvation and the effect of surface hydration on the ALD mechanism.