RESET-first Resistance Switching Mechanism of HfO 2 films with Ti electrode

RESET-first resistive switching mechanism in HfO2-x with Ti electrode was studied. RESET resistive switching was observed in annealed Ti/HfO2 film. The redox phenomenon from Ti/HfO2 to TiOx/HfO2-x was investigated with high angle annular dark field-scanning transmission electron microscopy, EDX, and x-ray photoelectron spectroscopy. Analysis shows that redox reaction from Ti/HfO2 to TiOx/HfO2-x was responsible for an increase of initial current with increasing the post-annealing temperature and the migration of oxygen ions at interface region under external electrical bias was contributed to bipolar resistive switching behavior.