A modified model of metal-semiconductor contacts is applied to analyze the capacitance-voltage and current-voltage characteristics of metal-ferroelectric-metal structures. The ferroelectricpolarization is considered as a sheet of surface charge situated at a fixed distance from the interface. The presumable high concentration of structural defects acting as active electric traps is taken into account by introducing a deep acceptorlike level. The model is applied on a set of metal- Pb ( Zr , Ti ) O 3 -metal samples with different Zr ∕ Ti ratios, deposited by different methods, and having different thicknesses, electrode materials, and electrode areas. Values around 10 18 cm − 3 were estimated for the hole concentration from capacitance-voltage measurements. The space-charge density near the electrode, estimated from current-voltage measurements, is in the 10 20 – 10 21 cm − 3 range. The total thickness of the interface layer ranges from 3 to 35 nm , depending on the Zr ∕ Ti ratio, on the shape of the hysteresis loop, and on the electrode material. The simulated I - V characteristics is fitted to the experimental one using the potential barrier and Richardson’s constant as parameters. The potential barrier is determined to be in the 1.09 – 1.37 eV range and Richardson’s constant is 520 A cm − 2 K − 2 .
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