Bipolar resistive switching behavior in Au/Pt–Fe2O3 core–shell nanoparticles assembly/Ti with 3 × 3 crossbar array structure

Abstract

The fabrication of 3×3 crossbar arrays with a width of 20μm is demonstrated. The bipolar resistive switching characteristics in Pt–Fe2O3 core–shell nanoparticles are investigated in the crossbar structure of top electrode (Au)/Pt–Fe2O3 nanoparticle assembly/bottom electrode (Ti) on SiO2/Si substrate. The monodisperse Pt–Fe2O3 nanoparticles with the diameter ∼15nm are chemically synthesized by the preferential oxidation of Fe and then pileup of Pt into the core in the presence of oleic acid and oleylamine at high temperature. The nanoparticles are assembled as a layer with a thickness of 50nm by repeated dip-coating. The Pt cores in the core–shell nanoparticles act as electron traps. The bipolar resistive switching behavior in Au/nanoparticle assembly/Ti device could be caused by the electron trapping and detrapping of the nanoparticles. The resistance ratio of HRS to LRS is ∼57 at a reading voltage of 0.5V. The value of reset voltage is 3.4V and that of set voltages is −1.0V.