Capacitance-voltage modeling of metal-ferroelectric-semiconductor capacitors based on epitaxial oxide heterostructures

We report a quantitative investigation on the capacitance-voltage (C-V) modeling of metal-ferroelectric-semiconductor epitaxial heterostructures based on a theoretical model. Within the carrier concentration between 10(17) and 10(21) cm(-3), calculated C-V curves were consistent with measurements exhibiting from a significant asymmetry to a typical butterfly shape resembling that of a metal-ferroelectric-metal capacitor. The behavior of the C-V curves can be understood by the width of the depletion region and the extent of the depolarization field. These results suggest that quantitative understanding on the electrical behavior of oxide heterostructures is possible with C-V measurements with potentially important implications on their device applications. (C) 2011 American Institute of Physics. [doi:10.1063/1.3561751]