Investigation on characteristics of resistance change by coexistence of oxygen vacancy and polarization reversal in MOD BaTiO3 ferroelectric thin film

摘要

In this work, we formed MOD BT thin films with chemical stoichiometry then investigated especially with consideration of final annealing condition in order to change the oxygen vacancy and ferroelectric properties. The films annealed in oxygen atmosphere showed the hysteresis of bipolar-type switching with current on/off ratio from 100 to 1000 for the both biases. It was especially noted that abrupt peaks of leakage current density occurred in the resistive hysteresis curve. We estimate that the abrupt increase in current density is the behaviors related to the polarization reversal due to ferroelectricity in the BaTiO film. However, the main resistive switching mode was not affected by their behaviors, thus suggesting that the polarization reversal is insufficient to control the total resistive hysteresis.