Electrical characterization and modelization of CaCu 3 Ti 4 O 12 polycrystalline ceramics

Since the observation almost 15 years ago of the so-called “colossal” dielectric permittivity behavior in CaCu 3 Ti 4 O 12 (CCTO) ceramics, several works have been undertaken to understand its physical origin interfacial polarization being the most likelihood. In this paper, ( C-V ) measurements, commonly used on semiconducting materials have been used to characterize CCTO samples. Their results may be described by a head-to-tail double metal-insulating-semiconductor (MIS) structure. A comparison between experimental and numerical simulation results of such a structure shows a good agreement, whatever the frequency range. Furthermore, this model explains the non-symmetrical behavior of the electrical response of this material, a property still not taken into account by today’s commonly known models.