Multimode threshold and bipolar resistive switching in bi-layered Pt-Fe2O3 core-shell and Fe2O3 nanoparticle assembly

Abstract

The bias-polarity dependent multimode threshold and bipolar resistive switching characteristics in bi-layered Pt-Fe2O3 core-shell and gamma-Fe2O3 nanoparticles assembly were investigated. The Ti/Pt-Fe2O3-core-shell-nanoparticles (similar to 20 nm)/gamma-Fe2O3-nanoparticles (similar to 40 nm)/Pt structure exhibited a threshold switching upon applying -V at Ti electrode. However, the filaments were formed at +V and subsequently ruptured at -V, featured to be bipolar switching. After rupturing filaments, it returned to threshold switching mode. The presence of core-shell nanoparticles facilitates the threshold switching either by temporary formation of filaments or enhanced charge transport. Also, the oxygen reservoir role of Ti electrode was essential to form stable filaments for bipolar switching. (C) 2013 American Institute of Physics. [http://dx.doi.org.openlink.unist.ac.kr:8080/10.1063/1.4798534]