Amorphous ZrO 2 Tunnel Junction Memristor With a Tunneling Electroresistance Ratio Above 400

An amorphous ZrO2 based tunneling junction memristor (TJM) with a tunneling electroresistance (TER) ratio above 400 is demonstrated. It is attributed to the modulation of tunneling barrier width induced by the accumulation of oxygen vacancies ( $V_{O}^{+}$ ) and negative charges near the ZrO2/semiconductor interface. The ferroelectric-like behaviors attributed to the voltage-modulated switching of the dipoles consisting of $V_{O}^{+}$ and negative charges in ZrO2 are characterized by a polarization-voltage test. The ZrO2 TJM achieves a TER ratio above 400 under 2.5/–1.5 V at 100 ns write/erase pulse condition, over 104 cycles program/erase endurance, and >104 s data retention.