Growth of La0.5Sr0.5CoO3 (LSCO) thin film on MgO epilayer buffered Si substrate was carried out by pulsed laser deposition (PLD) technique. By employing various characterization methods, such as reflection high-energy electron diffraction (RHEED), X-ray diffraction (XRD), atomic force microscopy (AFM), it can be found that substrate temperatures have huge impacts on the crystalline orientations, growth modes and surface morphologies of the LSCO thin films. Epitaxial LSCO thin film can be prepared at optimum substrate temperature. The obtained epitaxial film exhibits an atomic-scale smooth surface (RMS = 0.6 nm) and an excellent conductivity (electrical resistivity as low as 600 mu Omega cm), indicating that the epitaxial LSCO film could be used as a promising candidate of electrode material for the ferroelectric thin films. (c) 2007 Elsevier B.V. All rights reserved.