"Molecular Dynamics simulation about the critical thickness for pseudomorphic growth of

BaTiO₃ thin films on SrTiO₃ substrates"

Abstract

The deposition of defect free of BaTiO₃ thin films on SrTiO₃ (001) substrates at low temperatures is an important challenge for advanced electronic devices. The critical thickness at which the growth mechanism changes from epitaxial growth without defects into pseudomorphic growth by introducing a misfit dislocation is difficult to measure experimentally. Molecular dynamics simulations were performed in order to estimate this value and clarify the formation mechanism of misfit dislocations and stacking faults. Four different input models were tested and a sandwich model consisting of SrTiO₃ / BaTiO₃ / SrTiO₃ layers with different thicknesses was found to give the most reliable results. The interfacial energy for the strained BaTiO₃ thin film in comparison with the relaxed, but the misfit dislocation containing BaTiO₃ thin film was calculated for different temperatures and thicknesses. The comparison gives the value for the critical thickness, which decreases slightly with temperature.

Literature:

Wilfried Wunderlich, Masayuki Fujimoto, Hitoshi Ohsato,
Formation of stacking faults from Misfit Dislocations at the BaTiO3/SrTiO3 Interface simulated by Molecular Dynamics, Materials Science Engineering A [309-310] (2001) 148-151 pdf-file 509kB
Keywords: BaTiO3, Molecular Dynamics, Thin Film, Atomic structure of Stacking fault, Surface Energy

Wilfried Wunderlich, Masayuki Fujimoto, Hitoshi Ohsato,
Molecular Dynamics simulation about the stacking fault formation and critical thickness for pseudomorphic growth of BaTiO3 thin films on SrTiO3 substrates
Thin Solid Films [375] No.1-2 (2000) 9-14 pdf-file 321kB
Keywords: BaTiO3, Molecular Dynamics, Thin Film, Atomic structure of Stacking fault, Surface Energy

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