Roles of oxygen and nitrogen in control of nonlinear resistive behaviors via filamentary and homogeneous switching in an oxynitride thin film memristor

Abstract

A TiO_xN_y thin film, which contains controllable concentrations of oxygen and nitrogen by a single-step reactive sputtering process using a non-symmetric Pt electrode as top electrode and TiN as bottom electrode, exhibiting non-linear I–V behavior, was proposed and demonstrated. A switching model of the non-linear I–V switching was built based on diffusion of oxygen vacancies in the TiO_xN_y film with different ratios of O and N after the SET process. Effects on the switching relationship between TiO_xN_y and electrodes were investigated to optimize the best conditions for the non-linear behavior. The origin of the nonlinear property was investigated in detail by changing the compositions of oxygen and nitrogen in the TiO_xN_y thin film. We believe that these findings would open up opportunities to exploit resistive switching mechanisms and simple memristor stacking in next generation crossbar array applications.