First demonstration and performance improvement of ferroelectric HfO2-based resistive switch with low operation current and intrinsic diode property

We demonstrate, for the first time, a CMOS compatible ferroelectric HfO2-based two-terminal non-volatile resistive switch; HfO2 ferroelectric tunnel junction (FTJ). The device has characteristics of nA-range operation current, self-compliance, and intrinsic diode properties, as well as good device to device uniformity. Simultaneous achievement of these characteristics, which was not reported in the other two-terminal emerging memories, is significant advantage for future non-volatile applications. Accurate understanding of switching mechanism based on first-principles calculations and material characterization enabled us to establish a solid guideline for performance improvement: scaling of both ferroelectric layer and interfacial layer thickness. As a consequence, reduction of operation voltage while maintaining sufficient ON/OFF ratio was successfully demonstrated.