The SrTiO3/La0.9Sr0.1MnO3 (STO/LSMO) multilayers were fabricated on n-Si (1 0 0) substrates using a computer-controlled laser molecular-beam epitaxy (MBE) technique at 1x10(-2) Pa and 2x10(-4) Pa oxygen partial pressures, respectively. The dielectric properties of the multilayers (MLs) were investigated. The differences of the dielectric properties of the two samples were explained by an impedance analysis technique, which indicates that the interfacial polarization has a close relationship with the oxygen pressure. (C) 2010 Elsevier B. V. All rights reserved.