Experimental evidence of a ReRAM mechanism relying on <i>operando</i> nanometric depleted zone in V2O3 thin films

Abstract

Emerging Non-Volatile Memories are foreseen to be ideal candidates for new non-Von Neuman computing paradigms and yield performances superior to the eFlash memories, which will contest eFlash supremacy for embedded memories and automotive applications. In this work, an original Resistive Switching (RS) behavior is unveiled for one resistor V2O3 single device. In conventional Resistive Random Access Memories (ReRAMs), the first step relies on the commutation from a pristine High Resistive State (HRS) to a Low Resistive State (LRS), namely, the “forming” step. Here, unlike any other known ReRAMs or Phase-Change Memories, the non-volatile RS implies the creation of a depleted vanadium nanometric zone, during a unique first initialization step, which goes from the LRS pristine state to the HRS. This peculiar memory features the interplay of ionic migration, phase-change, and redox mechanisms. The memory behavior is corroborated by simulation, electrical, and chemico-physical characterizations. This new V2O3-based ReRAM presents promising single device performances with a large memory window, low operation voltages, excellent scalability, data retention extrapolated at 10 years of 110 °C and is forming-free.