Improvement of resistive switching performances via an amorphous ZrO_2 layer formation in TiO_2-based forming-free resistive random access memory

摘要

We present the effects of an amorphous ZrO_2 layer on the TiO_2-based bipolar resistive switching memory device where the ZrO_2 layer plays an important role as a supplementary reservoir of oxygen vacancies. Compared with Pt/TiO_2/Pt monolayer device, a remarkably improved uniformity of switching parameters such as switching voltages and resistances in high/low states is demonstrated in the Pt/ZrO_2/TiO_2/Pt system. The resistive switching mechanism of memory devices incorporating the ZrO_2/TiO_2 bilayer structure can be attributed to multiple conducting filaments through the occurrence of redox reactions at the ZrO_2/TiO_2 surface.