The influence of field-dependent carrier mobility and permittivity on space-charge-limited leakage current characteristics in high dielectric constant and ferroelectric thin films

Taking into account the electric field dependence of carrier mobility and permittivity, the current-voltage relationship dominated by space-charge-limited conduction for high dielectric constant ferroelectric thin films, consisting of (Ba, Sr)TiO
₃
and Pb(Zr, Ti)O
₃
is derived. Typical current-voltage characteristics are given by the derived relationship with empirical values for its parameters. The obtained current characteristics effectively account for the high-field current characteristics including the quasi-Ohmic region and the small power exponent law region in the electric field ranging from 10
⁶
V/cm to 10
⁷
V/cm observed experimentally in a very thin BaTiO
₃
single crystal in a previous study [Appl. Phys. Lett. 86 (2005) 152903].