Highly resolved conduction properties of ferroelectric/semiconductor diodes exhibiting memory effect

Three dimensionally aligned ferroelectric/semiconductor heterostructures were epitaxially grown, and their leakage current was measured. At low applied voltage, the leakage current through the heterostructures was relaxation-dominated and symmetric with regard to bias polarity. With increasing applied voltage, it became asymmetric and exhibited a reproducible memory effect, i.e., current-induced switching between high and low resistance states. These behaviors were observed in many combinations of ferroelectrics and perovskite-semiconductors. By regarding the ferroelectric as a semiconductor, the above observations are successfully explained.