Amorphous ZrO2 Tunnel Junction Memristor With a Tunneling Electroresistance Ratio Above 400

An amorphous ZrO ₂ 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 ZrO ₂ /semiconductor interface. The ferroelectric-like behaviors attributed to the voltage-modulated switching of the dipoles consisting of V _O ⁺ and negative charges in ZrO ₂ are characterized by a polarization-voltage test. The ZrO ₂ TJM achieves a TER ratio above 400 under 2.5/-1.5 V at 100 ns write/erase pulse condition, over 10 ⁴ cycles program/erase endurance, and >10 ⁴ s data retention.