Interfacial contribution to the dielectric response in semiconducting   LaBiMn4/3Co2/3O6
  Impedance measurements have been performed on a sintered polycrystalline sample of the perovskite LaBiMn4/3Co2/3O6. Colossal dielectric permittivity often is measured in this class of semiconducting materials as a result of extrinsic factors. Our results show that a large offset in the capacitance, measured on a series of samples with different thickness, is due to the interfacial polarization. This contribution then can be removed from the data, creating a general procedure for dielectric measurements in semiconducting samples. 
M.Filippi, B. Kundys, R. Ranjith, A.K. Kundu, W. Prellier