Measurement of Nonlinear Polarization of KTaO3 using Schottky Diodes

Capacitance vs bias voltage data are presented for Au–KTaO3 surface barrier Schottky diodes. Substantial deviations from the normal Schottky capacitance relationship have been observed and attributed to a field-dependent dielectric constant in the depletion layer. From the capacitance data obtained at room temperature, ε vs E and P vs E curves have been calculated for KTaO3 and found to be consistent with previous measurements made using conventional techniques at 4.2°K.