Study of the nucleation and growth of TiO2 and ZnO thin films by means of molecular dynamics simulations

The nucleation and growth of titanium dioxide (TiO₂) and zinc oxide (ZnO) thin films on Fe₂O₃ (hematite), Al₂O₃ (α-alumina) and SiO₂ (α-quartz) are studied by molecular dynamics simulations. The results show the formation of a strong interface region between the substrate and the film in the six systems studied here. A combination of polycrystalline and amorphous phases are observed in the TiO₂ films grown on the three substrates. ZnO deposition on the Fe₂O₃ and Al₂O₃ crystals yields a monocrystalline film growth. The ZnO film deposited on the SiO₂ crystal exhibits less crystallinity. The simulation results are compared with experimental results available in the literature.