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Thin films of strontium titanate, as well as its component oxides, have been of great interest due to their applicability
in electronic devices. In this manuscript we review our work to examine the growth of SrO, TiO2, and SrTiO3 (STO)
thin films on STO using classical molecular dynamics simulations. In particular, the simulations considered the
deposition of SrO and TiO2 molecules and stoichiometric STO clusters at incident energies of 0.1, 0.5, and 1.0
eV/atom onto the (001) surface of STO. The role of surface termination layer (SrO vs. TiO2), incident energy, and
incident particle size and deposition scheme in the case of STO deposition were investigated. In the case of SrO
deposition, smooth, ordered films were produced at all incident energies considered and for both surface
terminations. In contrast, in the case of TiO2 deposition, three-dimensional islands were formed under all the
conditions considered. The predicted growth modes were shown to be a consequence of the mobility and interaction
energy of each particle (SrO or TiO2) with the surface.
In the case of STO thin film growth three deposition schemes were explored: (i) alternating particle deposition
(APD), (ii) alternating monolayer deposition (AMD), and (iii) cluster deposition. For APD, a beam of alternating
SrO and TiO2 molecules was deposited on the (001) surface of STO with incident kinetic energies of 0.1, 0.5 or 1.0
eV/atom. AMD consisted of the deposition of alternating monolayers of pure SrO and TiO2, where both had incident
energies of 1.0 eV/atom. SrTiO3 cluster deposition considered the deposition of 1, 2, 3, and 4-unit STO
stoichiometric clusters with incident energies of 1.0 eV/atom. On the whole, some layer-by-layer growth was
predicted to occur on both SrO- and TiO2-terminated STO for each type of deposition scheme.
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