NbOx RRAM performance enhancement by surface modification with Au nanoparticles

Abstract

Resistive random-access memory (RRAM) has been widely studied because of its high information storage density and easy integration, and it has potential to replace traditional memory storage means. However, it is prone to random formations and fracture of conductive filaments, which limits its commercial applications. In this study, magnetron sputtering was used to deposit NbOx films on different substrates modified with different concentrations of Au-nanoparticles (NPs). The as developed Pt-Aumin/NbOx/W tip device with the lowest concentration of Au-NPs modified bottom electrode exhibited the best performance; the Vset distribution of the device was more concentrated, Vreset decreased significantly, the distribution range was narrow, and the resistance distribution of high and low resistance states (HRS and LRS, respectively) was more stable. Modification of the bottom electrode with Au-NPs did not change the ohmic conduction behavior of NbOx RRAM in LRS; however, it changed the resistance switching mechanism from SCLC to P–F effect modified SCLC. The Au-NPs modified bottom electrode acted like a tip, enhancing the local electric field and promoting the formation of conductive filaments near the NPs. This work explains the internal mechanism for improving RRAM properties using a local electric field and provides theoretical guidance for enabling the rapid commercialization of RRAM.