title: Nucleation kinetics of SrTiO3 3D islands and nanorings on Si substrates.
abstract: The nucleation of SrTiO3 three-dimensional (3D) islands and nanorings on Si substrates via a novel metalorganic decomposition (MOD) process has been investigated as a function of temperature and solution concentration of the SrTi(OC3H7)6 precursor. Quantitative analysis of island density and size distribution by atomic force microscopy (AFM) has revealed the existence of a nucleation regime at solution concentrations below 5 × 10(-3) M, in which the critical nucleus is a trimer and a coalescence regime at higher concentrations, dominated by growth of immobile clusters. Nanorings form preferentially under high supersaturation conditions and their size distribution is consistent with a dynamic coalescence. On the basis of recent theoretical models (Gill, 2012), we have proposed that the island-to-nanoring transition in the SrTiO3/Si system occurs above a critical size as a result of a competition between energetic and kinetic factors. The combination of high-resolution transmission electron microscopy (HRTEM) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) has shown that the monocrystalline SrTiO3 nanoclusters grow pseudomorphically on the Si substrate and exhibit a strain-induced tetragonal lattice distortion.
authors.affiliation: Instituto de Ciencia de Materiales de Madrid, CSIC, C/Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain. ptejedor@icmm.csic.es.
authors.forename: Paloma
authors.initials: P
authors.lastname: Tejedor
authors.forename: Marcos
authors.initials: M
authors.lastname: Benedicto
authors.forename: Luis
authors.initials: L
authors.lastname: Vázquez
authors.forename: Beatriz
authors.initials: B
authors.lastname: Galiana